[Study on condition for extraction of arctiin from fruits of Arctium lappa using supercritical fluid extraction].

PubMed

Dong, Wen-hong; Liu, Ben

2006-08-01

To study the feasibility of supercritical fluid extraction (SFE) for arctiin from the fruits of Arctium lappa. The extracts were analyzed by HPLC, optimum extraction conditions were studied by orthogonal tests. The optimal extraction conditions were: pressure 40 MPa, temperature 70 degrees C, using methanol as modifier carrier at the rate of 0.55 mL x min(-1), static extraction time 5 min, dynamic extraction 30 min, flow rate of CO2 2 L x min(-1). SFE has the superiority of adjustable polarity, and has the ability of extracting arctiin.

Supercritical fluid extraction of peach (Prunus persica) almond oil: process yield and extract composition.

PubMed

Mezzomo, Natália; Mileo, Bruna R; Friedrich, Maria T; Martínez, Julian; Ferreira, Sandra R S

2010-07-01

Peach kernels are industrial residues from the peach processing, contain oil with important therapeutic properties and attractive nutritional aspects because of the high concentration of oleic and linoleic acids. The extraction method used to obtain natural compounds from raw matter is critical for product quality definition. Thus, the aim of this work was to compare peach almond extraction yields obtained by different procedures: soxhlet extractions (Sox) with different solvents; hydrodistillation (HD); ethanolic maceration (Mac) followed by fractionation with various solvents, and supercritical fluid extraction (SFE) at 30, 40 and 50 degrees C and at 100, 200 and 300bar, performed with pure CO(2) and with a co-solvent. The extracts were evaluated with respect to fatty acid composition (FAC), fractionated chemical profile (FCP) and total phenolic content (TPC). The Sox total yields were generally higher than those obtained by SFE. The crossover pressure for SFE was between 260 and 280bar. The FAC results show oleic and linoleic acids as main components, especially for Sox and SFE extracts. The FCP for samples obtained by Sox and Mac indicated the presence of benzaldehyde and benzyl alcohol, components responsible for almond flavor and with important industrial uses, whereas the SFE extracts present a high content of a possible flavonoid. The higher TPC values were obtained by Sox and Mac with ethanol. In general, the maximum pressure in SFE produced the highest yield, TPC and oleic acid content. The use of ethanol at 5% as co-solvent in SFE did not result in a significant effect on any evaluated parameter. The production of peach almond oil through all techniques is substantially adequate and SFE presented advantages, with respect to the quality of the extracts due to the high oleic acid content, as presented by some Sox samples. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

[Study on new extraction technology of astragaloside IV].

PubMed

Sun, Haiyan; Guan, Su; Huang, Min

2005-08-01

To explore the possibility and the optimal extraction technology of astragaloside IV by SFE-CO2. According the content of astragaloside IV, the optimum extraction technology parameters such as extraction temperature, pressure, extraction time, velocity of fluid and co-solvent were investigated and the result was compared with that of water extraction. The optimum technical parameters were as follows: Extracting pressure 40 Mpa, temperature 45 degrees C, extracting time 2h, co-solvent was 95% ethanol and its dosage was 4ml/g, the ratio of CO2 fluid was 10 kg/kg x h. Extraction technology of astragaloside IV by SFE-CO2 is reliable, stable.

Supercritical Fluid Extraction of Toxic Heavy Metals and Uranium from Acidic Solutions with Sulfur-Containing Organophosphorus Reagents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Yuehe; Liu, Chongxuan; Wu, Hong

2003-03-02

The feasibility of using sulfur-containing organophosphorus reagents for the chelation-supercritical fluid extraction (SFE) of toxic heavy metals and uranium from acidic media was investigated. The SFE experiments were conducted in a specially-designed flow-through liquid extractor. Effective extraction of the metal ions from various acidic media was demonstrated. The effect of ligand concentration in supercritical CO{sub 2} on the kinetics of metal extraction was studied. A simplified model is used to describe the extraction kinetics and the good agreement of experimental data with the equilibrium-based model is achieved.

Comparison of different methods for extraction from Tetraclinis articulata: yield, chemical composition and antioxidant activity.

PubMed

Herzi, Nejia; Bouajila, Jalloul; Camy, Séverine; Romdhane, Mehrez; Condoret, Jean-Stéphane

2013-12-15

In the present study, three techniques of extraction: hydrodistillation (HD), solvent extraction (conventional 'Soxhlet' technique) and an innovative technique, i.e., the supercritical fluid extraction (SFE), were applied to ground Tetraclinis articulata leaves and compared for extraction duration, extraction yield, and chemical composition of the extracts as well as their antioxidant activities. The extracts were analyzed by GC-FID and GC-MS. The antioxidant activity was measured using two methods: ABTS(•+) and DPPH(•). The yield obtained using HD, SFE, hexane and ethanol Soxhlet extractions were found to be 0.6, 1.6, 40.4 and 21.2-27.4 g/kg respectively. An original result of this study is that the best antioxidant activity was obtained with an SFE extract (41 mg/L). The SFE method offers some noteworthy advantages over traditional alternatives, such as shorter extraction times, low environmental impact, and a clean, non-thermally-degraded final product. Also, a good correlation between the phenolic contents and the antioxidant activity was observed with extracts obtained by SFE at 9 MPa. Copyright © 2013 Elsevier Ltd. All rights reserved.

Mass balance of metal species in supercritical fluid extraction using sodium diethyldithiocarbamate and dibutylammonium dibutyldithiocarbamate.

PubMed

Wang, Joanna Shaofen; Chiu, Kong-Hwa

2006-03-01

The objective of this work is to track the amount of metal complexes distributed in the extraction cell, collection vial, and tubing used in supercritical fluid extraction (SFE) systems after progressive removal of metal ions in supercritical carbon dioxide (SC-CO2). Sodium diethyldithiocarbamate (NaDDC) and dibutylammonium dibutyldithiocarbamate (DBDC) ligands were used to form complexes with Cd, Cu, Pb, and Zn and CO(2)/5% methanol as a supercritical fluid. The mass balance of metal complexes were obtained before and after extraction, and metals in different locations in the system were flushed out using an organic solvent and nitric acid (HNO3). These results infer that the stability constant (beta) of the metal-ligand complex has a strong correlation with SFE. Because of the composition of the stainless-steel cell, Fe, Cr, and Ni or other trace elements in the cell might interfere with the mass balance of metal complexes in SFE due to an exchange mechanism taking place between the cell and the sample.

On-line supercritical fluid extraction-supercritical fluid chromatography-mass spectrometry of polycyclic aromatic hydrocarbons in soil.

PubMed

Wicker, A Paige; Carlton, Doug D; Tanaka, Kenichiro; Nishimura, Masayuki; Chen, Vivian; Ogura, Tairo; Hedgepeth, William; Schug, Kevin A

2018-06-01

On-line supercritical fluid extraction - supercritical fluid chromatography - mass spectrometry (SFE-SFC-MS) has been applied for the determination of polycyclic aromatic hydrocarbons (PAHs) in soil. The purpose of this study was to develop and validate the first on-line SFE-SFC-MS method for the quantification of PAHs in various types of soil. By coupling the sample extraction on-line with chromatography and detection, sample preparation is minimized, diminishing sample loss and contamination, and significantly decreasing the required extraction time. Parameters for on-line extraction coupled to chromatographic analysis were optimized. The method was validated for concentrations of 10-1500 ng of PAHs per gram of soil in Certified Reference Material (CRM) sediment, clay, and sand with R 2  ≥ 0.99. Limits of detection (LOD) were found in the range of 0.001-5 ng/g, and limits of quantification (LOQ) in the range of 5-15 ng/g. The method developed in this study can be effectively applied to the study of PAHs in the environment, and may lay the foundation for further applications of on-line SFE-SFC-MS. Copyright © 2018 Elsevier B.V. All rights reserved.

Phytosterols and their extraction from various plant matrices using supercritical carbon dioxide: a review.

PubMed

Uddin, Md Salim; Sarker, Md Zaidul Islam; Ferdosh, Sahena; Akanda, Md Jahurul Haque; Easmin, Mst Sabina; Bt Shamsudin, Siti Hadijah; Bin Yunus, Kamaruzzaman

2015-05-01

Phytosterols provide important health benefits: in particular, the lowering of cholesterol. From environmental and commercial points of view, the most appropriate technique has been searched for extracting phytosterols from plant matrices. As a green technology, supercritical fluid extraction (SFE) using carbon dioxide (CO2) is widely used to extract bioactive compounds from different plant matrices. Several studies have been performed to extract phytosterols using supercritical CO2 (SC-CO2) and this technology has clearly offered potential advantages over conventional extraction methods. However, the efficiency of SFE technology fully relies on the processing parameters, chemistry of interest compounds, nature of the plant matrices and expertise of handling. This review covers SFE technology with particular reference to phytosterol extraction using SC-CO2. Moreover, the chemistry of phytosterols, properties of supercritical fluids (SFs) and the applied experimental designs have been discussed for better understanding of phytosterol solubility in SC-CO2. © 2014 Society of Chemical Industry.

Multivessel supercritical fluid extraction of food items in Total Diet Study.

PubMed

Hopper, M L; King, J W; Johnson, J H; Serino, A A; Butler, R J

1995-01-01

An off-line, large capacity, multivessel supercritical fluid extractor (SFE) was designed and constructed for extraction of large samples. The extractor can simultaneously process 1-6 samples (15-25 g) by using supercritical carbon dioxide (SC-CO2), which is relatively nontoxic and nonflammable, as the solvent extraction medium. Lipid recoveries for the SFE system were comparable to those obtained by blending or Soxhlet extraction procedures. Extractions at 10,000 psi, 80 degrees C, expanded gaseous CO2 flow rates of 4-5 L/min (35 degrees C), and 1-3 h extraction times gave reproducible lipid recoveries for pork sausage (relative standard deviation [RSD], 1.32%), corn chips (RSD, 0.46%), cheddar cheese (RSD, 1.14%), and peanut butter (RSD, 0.44%). In addition, this SFE system gave reproducible recoveries (> 93%) for butter fortified with cis-chlordane and malathion at the 100 ppm and 0.1 ppm levels. Six portions each of cheddar cheese, saltine crackers, sandwich cookies, and ground hamburger also were simultaneously extracted with SC-CO2 and analyzed for incurred pesticide residues. Results obtained with this SFE system were reproducible and comparable with results from organic-solvent extraction procedures currently used in the Total Diet Study; therefore, use and disposal of large quantities of organic solvents can be eliminated.

Comparison of ASE and SFE with Soxhlet, Sonication, and Methanolic Saponification Extractions for the Determination of Organic Micropollutants in Marine Particulate Matter.

PubMed

Heemken, O P; Theobald, N; Wenclawiak, B W

1997-06-01

The methods of accelerated solvent extraction (ASE) and supercritical fluid extraction (SFE) of polycyclic aromatic hydrocarbons (PAHs), aliphatic hydrocarbons, and chlorinated hydrocarbons from marine samples were investigated. The results of extractions of a certified sediment and four samples of suspended particulate matter (SPM) were compared to classical Soxhlet (SOX), ultrasonication (USE), and methanolic saponification extraction (MSE) methods. The recovery data, including precision and systematic deviations of each method, were evaluated statistically. It was found that recoveries and precision of ASE and SFE compared well with the other methods investigated. Using SFE, the average recoveries of PAHs in three different samples ranged from 96 to 105%, for ASE the recoveries were in the range of 97-108% compared to the reference methods. Compared to the certified values of sediment HS-6, the average recoveries of SFE and ASE were 87 and 88%, most compounds being within the limits of confidence. Also, for alkanes the average recoveries by SFE and ASE were equal to the results obtained by SOX, USE, and MSE. In the case of SFE, the recoveries were in the range 93-115%, and ASE achieved recoveries of 94-107% as compared to the other methods. For ASE and SFE, the influence of water on the extraction efficiency was examined. While the natural water content of the SPM sample (56 wt %) led to insufficient recoveries in ASE and SFE, quantitative extractions were achieved in SFE after addition of anhydrous sodium sulfate to the sample. Finally, ASE was applied to SPM-loaded filter candles whereby a mixture of n-hexane/acetone as extraction solvent allowed the simultaneous determination of PAHs, alkanes, and chlorinated hydrocarbons.

A comparative study of conventional and supercritical fluid extraction methods for the recovery of secondary metabolites from Syzygium campanulatum Korth.

PubMed

Memon, Abdul Hakeem; Hamil, Mohammad Shahrul Ridzuan; Laghari, Madeeha; Rithwan, Fahim; Zhari, Salman; Saeed, Mohammed Ali Ahmed; Ismail, Zhari; Majid, Amin Malik Shah Abdul

2016-09-01

Syzygium campanulatum Korth is a plant, which is a rich source of secondary metabolites (especially flavanones, chalcone, and triterpenoids). In our present study, three conventional solvent extraction (CSE) techniques and supercritical fluid extraction (SFE) techniques were performed to achieve a maximum recovery of two flavanones, chalcone, and two triterpenoids from S. campanulatum leaves. Furthermore, a Box-Behnken design was constructed for the SFE technique using pressure, temperature, and particle size as independent variables, and yields of crude extract, individual and total secondary metabolites as the dependent variables. In the CSE procedure, twenty extracts were produced using ten different solvents and three techniques (maceration, soxhletion, and reflux). An enriched extract of five secondary metabolites was collected using n-hexane:methanol (1:1) soxhletion. Using food-grade ethanol as a modifier, the SFE methods produced a higher recovery (25.5%‒84.9%) of selected secondary metabolites as compared to the CSE techniques (0.92%‒66.00%).

A comparative study of conventional and supercritical fluid extraction methods for the recovery of secondary metabolites from Syzygium campanulatum Korth#

PubMed Central

Memon, Abdul Hakeem; Hamil, Mohammad Shahrul Ridzuan; Laghari, Madeeha; Rithwan, Fahim; Zhari, Salman; Saeed, Mohammed Ali Ahmed; Ismail, Zhari; Majid, Amin Malik Shah Abdul

2016-01-01

Syzygium campanulatum Korth is a plant, which is a rich source of secondary metabolites (especially flavanones, chalcone, and triterpenoids). In our present study, three conventional solvent extraction (CSE) techniques and supercritical fluid extraction (SFE) techniques were performed to achieve a maximum recovery of two flavanones, chalcone, and two triterpenoids from S. campanulatum leaves. Furthermore, a Box-Behnken design was constructed for the SFE technique using pressure, temperature, and particle size as independent variables, and yields of crude extract, individual and total secondary metabolites as the dependent variables. In the CSE procedure, twenty extracts were produced using ten different solvents and three techniques (maceration, soxhletion, and reflux). An enriched extract of five secondary metabolites was collected using n-hexane:methanol (1:1) soxhletion. Using food-grade ethanol as a modifier, the SFE methods produced a higher recovery (25.5%‒84.9%) of selected secondary metabolites as compared to the CSE techniques (0.92%‒66.00%). PMID:27604860

Comparison study of moisture content, colour properties and essential oil compounds extracted by hydrodistillation and supercritical fluid extraction between stem and leaves of lemongrass (Cymbopogun citratus)

NASA Astrophysics Data System (ADS)

Kamaruddin, Shazlin; Mustapha, Wan Aida Wan; Haiyee, Zaibunnisa Abdul

2018-04-01

The objectives of this study were to compare the properties of moisture content, colour and essential oil compounds between stem and leaves of lemongrass (Cymbopogun citratus). The essential oil was extracted using two different methods which are hydrodistillation and supercritical fluid extraction (SFE). There was no significant difference of moisture content between stem and leaves of lemongrass. The lightness (L) and yellowness (+b) values of the stems were significantly higher (p<0.05) compared to the leaves. The highest yield of essential oil was obtained by extraction using supercritical fluid extraction (SFE) in leaves (˜ 0.7%) by treatment at 1700psi and 50°C. The main compound of extracted essential oil was citral (geranial and neral).

CLEANING UP PESTICIDE CONTAMINATED SOILS: COMPARING EFFECTIVENESS OF SUPERCRITICAL FLUID EXTRACTION WITH SOLVENT EXTRACTION AND LOW TEMPERATURE THERMAL DESORPTION

EPA Science Inventory

Bench-scale supercritical fluid extraction (SFE) studies were performed on soil samples obtained from a Superfund site that is contaminated with high levels of p,p,-DDT, p,p,-DDD, p,p,-DDE, toxaphene and hexachlorocyclohexane. The effectiveness of supercritical fluid extraction ...

Optimization of microwave-assisted extraction and supercritical fluid extraction of carbamate pesticides in soil by experimental design methodology.

PubMed

Sun, Lei; Lee, Hian Kee

2003-10-03

Orthogonal array design (OAD) was applied for the first time to optimize microwave-assisted extraction (MAE) and supercritical fluid extraction (SFE) conditions for the analysis of four carbamates (propoxur, propham, methiocarb, chlorpropham) from soil. The theory and methodology of a new OA16 (4(4)) matrix derived from a OA16 (2(15)) matrix were developed during the MAE optimization. An analysis of variance technique was employed as the data analysis strategy in this study. Determinations of analytes were completed using high-performance liquid chromatography (HPLC) with UV detection. Four carbamates were successfully extracted from soil with recoveries ranging from 85 to 105% with good reproducibility (approximately 4.9% RSD) under the optimum MAE conditions: 30 ml methanol, 80 degrees C extraction temperature, and 6-min microwave heating. An OA8 (2(7)) matrix was employed for the SFE optimization. The average recoveries and RSD of the analytes from spiked soil by SFE were 92 and 5.5%, respectively except for propham (66.3+/-7.9%), under the following conditions: heating for 30 min at 60 degrees C under supercritical CO2 at 300 kg/cm2 modified with 10% (v/v) methanol. The composition of the supercritical fluid was demonstrated to be a crucial factor in the extraction. The addition of a small volume (10%) of methanol to CO2 greatly enhanced the recoveries of carbamates. A comparison of MAE with SFE was also conducted. The results indicated that >85% average recoveries were obtained by both optimized extraction techniques, and slightly higher recoveries of three carbamates (propoxur, propham and methiocarb) were achieved using MAE. SFE showed slightly higher recovery for chlorpropham (93 vs. 87% for MAE). The effects of time-aged soil on the extraction of analytes were examined and the results obtained by both methods were also compared.

Phytochemical profile and anticholinesterase and antimicrobial activities of supercritical versus conventional extracts of Satureja montana.

PubMed

Silva, Filipa V M; Martins, Alice; Salta, Joana; Neng, Nuno R; Nogueira, José M F; Mira, Delfina; Gaspar, Natália; Justino, Jorge; Grosso, Clara; Urieta, José S; Palavra, António M S; Rauter, Amélia P

2009-12-23

Winter savory Satureja montana is a medicinal herb used in traditional gastronomy for seasoning meats and salads. This study reports a comparison between conventional (hydrodistillation, HD, and Soxhlet extraction, SE) and alternative (supercritical fluid extraction, SFE) extraction methods to assess the best option to obtain bioactive compounds. Two different types of extracts were tested, the volatile (SFE-90 bar, second separator vs HD) and the nonvolatile fractions (SFE-250 bar, first and second separator vs SE). The inhibitory activity over acetyl- and butyrylcholinesterase by S. montana extracts was assessed as a potential indicator for the control of Alzheimer's disease. The supercritical nonvolatile fractions, which showed the highest content of (+)-catechin, chlorogenic, vanillic, and protocatechuic acids, also inhibited selectively and significantly butyrylcholinesterase, whereas the nonvolatile conventional extract did not affect this enzyme. Microbial susceptibility tests revealed the great potential of S. montana volatile supercritical fluid extract for the growth control and inactivation of Bacillus subtilis and Bacillus cereus, showing some activity against Botrytis spp. and Pyricularia oryzae. Although some studies were carried out on S. montana, the phytochemical analysis together with the biological properties, namely, the anticholinesterase and antimicrobial activities of the plant nonvolatile and volatile supercritical fluid extracts, are described herein for the first time.

Supercritical fluid extraction from spent coffee grounds and coffee husks: antioxidant activity and effect of operational variables on extract composition.

PubMed

Andrade, Kátia S; Gonçalvez, Ricardo T; Maraschin, Marcelo; Ribeiro-do-Valle, Rosa Maria; Martínez, Julian; Ferreira, Sandra R S

2012-01-15

The present study describes the chemical composition and the antioxidant activity of spent coffee grounds and coffee husks extracts, obtained by supercritical fluid extraction (SFE) with CO(2) and with CO(2) and co-solvent. In order to evaluate the high pressure method in terms of process yield, extract composition and antioxidant activity, low pressure methods, such as ultrasound (UE) and soxhlet (SOX) with different organic solvents, were also applied to obtain the extracts. The conditions for the SFE were: temperatures of 313.15K, 323.15K and 333.15K and pressures from 100 bar to 300 bar. The SFE kinetics and the mathematical modeling of the overall extraction curves (OEC) were also investigated. The extracts obtained by LPE (low pressure extraction) with ethanol showed the best results for the global extraction yield (X(0)) when compared to SFE results. The best extraction yield was 15±2% for spent coffee grounds with ethanol and 3.1±04% for coffee husks. The antioxidant potential was evaluated by DPPH method, ABTS method and Folin-Ciocalteau method. The best antioxidant activity was showed by coffee husk extracts obtained by LPE. The quantification and the identification of the extracts were accomplished using HPLC analysis. The main compounds identified were caffeine and chlorogenic acid for the supercritical extracts from coffee husks. Copyright © 2011 Elsevier B.V. All rights reserved.

Kenaf seed supercritical fluid extract reduces aberrant crypt foci formation in azoxymethane-induced rats.

PubMed

Ghafar, Siti Aisyah Abd; Yazan, Latifah Saiful; Tahir, Paridah Md; Ismail, Maznah

2012-03-01

Kenaf (Hibiscus cannabinus) a plant of the family Malvaceae, is a valuable fiber plant native to India and Africa. Kenaf seeds contain alpha-linolenic acid, phytosterol such as β-sitosterol, vitamin E and other antioxidants with chemopreventive properties. In the present study we examined the hypothesis that kenaf seed 'supercritical fluid extract' (SFE) extract could suppress the early colon carcinogenesis in vivo by virtue of its bioactive compounds. To accomplish this goal, 60 male rats were randomly assigned to 5 groups which were (1) negative control group [not induced with azoxymethane (AOM)]; (2) positive control group (induced with AOM but received no treatment); (3) group treated with 500 mg/kg kenaf seed SFE extract; (4) group treated with 1000 mg/kg kenaf seed SFE extract; (5) group treated with 1500 mg/kg kenaf seed SFE extract. At 7 weeks of age, all rats except the negative control group received 15 mg/kg of AOM injection subcutaneously once a week for 2 weeks. Rats were euthanized at 13 weeks of the experiment. Number of ACF (mean±SD) ranged from 84.4±4.43 to 179.5±12.78 in group 2, 3, 4, 5. ACF reductions compared with the untreated group were 45.3, 51.4 and 53.1% in rats fed with 500, 1000 and 1500 mg/kg body weight, respectively. There were no significant differences in weight gain among groups. Our finding indicates that kenaf seed SFE extract reduced AOM-induced ACF in Sprague-Dawley male rats. Copyright © 2010 Elsevier GmbH. All rights reserved.

Instrument for Analysis of Organic Compounds on Other Planets

NASA Technical Reports Server (NTRS)

Daulton, Riley M.; Hintze, Paul E.

2016-01-01

The goal of this project is to develop the Instrument for Solvent Extraction and Analysis of Extraterrestrial Bodies using In Situ Resources (ISEE). Specifically, ISEE will extract and characterize organic compounds from regolith which is found on the surface of other planets or asteroids. The techniques this instrument will use are supercritical fluid extraction (SFE) and supercritical fluid chromatography (SFC). ISEE aligns with NASA's goal to expand the frontiers of knowledge, capability, and opportunities in space in addition to supporting NASA's aim to search for life elsewhere by characterizing organic compounds. The outcome of this project will be conceptual designs of 2 components of the ISEE instrument as well as the completion of proof-of-concept extraction experiments to demonstrate the capabilities of SFE. The first conceptual design is a pressure vessel to be used for the extraction of the organic compounds from the regolith. This includes a comparison of different materials, geometry's, and a proposition of how to insert the regolith into the vessel. The second conceptual design identifies commercially available fluid pumps based on the requirements needed to generate supercritical CO2. The proof-of-concept extraction results show the percent mass lost during standard solvent extractions of regolith with organic compounds. This data will be compared to SFE results to demonstrate the capabilities of ISEE's approach.

Comparison of supercritical fluid and Soxhlet extractions for the quantification of hydrocarbons from Euphorbia macroclada.

PubMed

Ozcan, Adnan; Ozcan, Asiye Safa

2004-10-08

This study compares conventional Soxhlet extraction and analytical scale supercritical fluid extraction (SFE) for their yields in extracting of hydrocarbons from arid-land plant Euphorbia macroclada. The plant material was firstly sequentially extracted with supercritical carbon dioxide, modified with 10% methanol (v/v) in the optimum conditions that is a pressure of 400atm and a temperature of 50 degrees C and then it was sonicated in methylene chloride for an additional 4h. E. macroclada was secondly extracted by using a Soxhlet apparatus at 30 degrees C for 8h in methylene chloride. The validated SFE was then compared to the extraction yield of E. macroclada with a Soxhlet extraction by using the Student's t-test at the 95% confidence level. All of extracts were fractionated with silica-gel in a glass column to get better hydrocarbon yields. Thus, the highest hydrocarbons yield from E. macroclada was achieved with SFE (5.8%) when it compared with Soxhlet extractions (1.1%). Gas chromatography (GC) analysis was performed to determine the quantitative hydrocarbons from plant material. The greatest quantitative hydrocarbon recovery from GC was obtained by supercritical carbon dioxide extract (0.6mgg(-1)).

Isolation of essential oil from different plants and herbs by supercritical fluid extraction.

PubMed

Fornari, Tiziana; Vicente, Gonzalo; Vázquez, Erika; García-Risco, Mónica R; Reglero, Guillermo

2012-08-10

Supercritical fluid extraction (SFE) is an innovative, clean and environmental friendly technology with particular interest for the extraction of essential oil from plants and herbs. Supercritical CO(2) is selective, there is no associated waste treatment of a toxic solvent, and extraction times are moderate. Further, supercritical extracts were often recognized of superior quality when compared with those produced by hydro-distillation or liquid-solid extraction. This review provides a comprehensive and updated discussion of the developments and applications of SFE in the isolation of essential oils from plant matrices. SFE is normally performed with pure CO(2) or using a cosolvent; fractionation of the extract is commonly accomplished in order to isolate the volatile oil compounds from other co-extracted substances. In this review the effect of pressure, temperature and cosolvent on the extraction and fractionation procedure is discussed. Additionally, a comparison of the extraction yield and composition of the essential oil of several plants and herbs from Lamiaceae family, namely oregano, sage, thyme, rosemary, basil, marjoram and marigold, which were produced in our supercritical pilot-plant device, is presented and discussed. Copyright © 2012 Elsevier B.V. All rights reserved.

Preparative isolation and purification of capsaicin and dihydrocapsaicin from Capsici Fructus using supercritical fluid extraction combined with high speed countercurrent chromatography.

PubMed

Yan, Rongwei; Zhao, Leilei; Tao, Junfei; Zou, Yong; Xu, Xinjun

2018-05-01

Supercritical fluid extraction with CO 2 (SFE-CO 2 ) was utilized for extraction of capsaicin (CA) and dihydrocapsaicin (DHCA) from Capsici Fructus, and then a two-step enrichment method for separating capsaicinoids from SFE-CO 2 extracts was developed. The process involved extraction with aqueous methanol and crystallization by alkali extraction and acid precipitation. Finally, a consecutive high-speed countercurrent chromatography (HSCCC) separation method was successfully applied in the purification of CA and DHCA from capsaicinoid crystal. The extraction pressure, extraction temperature and volume of co-solvent were optimized at 33 MPa, 41 °C and 75 mL, respectively, using response surface methodology; the extraction rates of CA and DHCA were about 93.18% and 93.49%, respectively. 407.43 mg capsaicinoid crystal was isolated from the SFE-CO 2 extracts obtained from 100 g capsicum powder by the two-step enrichment method. About 506 mg and 184 mg CA and DHCA with purities up to 98.31% and 96.68%, respectively, were obtained from 1 g capsaicinoid crystal in one HSCCC of three consecutive sample loadings without exchanging any solvent system. This method comprising SFE-CO 2 , a two-step enrichment and HSCCC was efficient, powerful and practical for the large-scale preparation of CA and DHCA from Capsici Fructus with high purity and high yield. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

SUPERCRITICAL FLUID EXTRACTION OF POLYCYCLIC AROMATIC HYDROCARBON MIXTURES FROM CONTAMINATED SOILS

EPA Science Inventory

Highly contaminated (with PAHs) topsoils were extracted with supercritical CO₂ to determine the feasibility and mechanism of supercritical fluid extraction (SFE). Effect of SCF density, temperature, cosolvent type and amount, and of slurrying the soil with water were ...

Characterization of Linum usitatissimum L. oil obtained from different extraction technique and in vitro antioxidant potential of supercritical fluid extract

PubMed Central

Chauhan, Rishika; Chester, Karishma; Khan, Yasmeen; Tamboli, Ennus Tajuddin; Ahmad, Sayeed

2015-01-01

Aim: Present investigation was aimed to characterize the fixed oil of Linum usitatissimum L. using five different extraction methods: Supercritical fluid extraction (SFE), ultrasound-assistance, soxhlet extraction, solvent extraction, and three phase partitioning method. Materials and Methods: The SFE conditions (temperature, pressure, and volume of CO2) were optimized prior for better yield. The extracted oils were analyzed and compared for their physiochemical parameters, high performance thin layer chromatography (HPTLC), gas chromatography-mass spectrometry (GC-MS), and Fourier-transformed infrared spectroscopy (FT-IR) fingerprinting. Antioxidant activity was also determined using 1,1-diphenyl-2-picrylhydrazyl and superoxide scavenging method. Result: The main fatty acids were α-linolenic acid, linoleic acid, palmitic acid, and stearic acid as obtained by GC-MS. HPTLC analysis revealed the presence of similar major components in chromatograms. Similarly, the pattern of peaks, as obtained in FT-IR and GC-MS spectra of same oils by different extraction methods, were superimposable. Conclusion: Analysis reported that the fixed oil of L. usitatissimum L. is a good source of n-3 fatty acid with the significant antioxidant activity of oil obtained from SFE extraction method. PMID:26681884

[Studies on technology of supercritical-CO2 fluid extraction for volatile oils and saikosaponins in Bupleurum chinense DC].

PubMed

Ge, F H; Li, Y; Xie, J M; Li, Q; Ma, G J; Chen, Y H; Lin, Y C; Li, X F

2000-03-01

To study the technology of supercritical-CO2 fluid extraction (SFE-CO2) for the volatile oils and saikosaponins in Bupleurum chinense. Exploring the effects of pressure, temperature, extraction time, flow rate of CO2 and entrainers on the yield of the oils and saikosaponin-contained extracts; determining the optimum conditions for SFE-CO2; analyzing the oils by GC/MS and comparing the technology of SFE-CO2 with that of traditional steam distillation. The optimum extraction conditions turned out to be--for volatile oils: pressure (EP) = 20 MPa, temperature (ET) = 30 degrees C, isolator I pressure (1P-I) = 12 MPa, temperature(1T-I) = 65 degrees C, isolator II pressure (1P-II) = 6 MPa, temperature (1T-II) = 40 degrees C, extraction time = 4 hours, and CO2 flow rate = 10-20 kg.(h.kg)-1 crude drug; for saikosaponins: EP = 30 MPa, ET = 65 degrees C, 1P I = 12 MPa, 1T I = 55 degrees C, 1P II = 6 MPa, 1T II = 43 degrees C, extraction time = 3 hours, entrainer = 60% ethanol, and CO2 flow rate = 20-25 kg.(h.kg)-1 crude drug. SFE-CO2 excels the traditional steam distillation in raising yield and reducing extraction time. The oils are composed of 22 constituents including caproaldehyde, and the saikosaponins can only be extracted with the help of entrainers under higher pressure and temperature.

Chemical composition of the SFE-CO extracts from Cajanus cajan (L.) Huth and their antimicrobial activity in vitro and in vivo.

PubMed

Zu, Yuan-gang; Liu, Xiao-lei; Fu, Yu-jie; Wu, Nan; Kong, Yu; Wink, Michael

2010-12-01

The in vitro and in vivo antimicrobial activities of SFE-CO₂(supercritical fluid extraction) extracts and ethanol extracts from Cajanus cajan (L.) Huth were investigated. The flavonoid compounds orientin, vitexin, isovitexin, pinostrobin and the stilbene cajaninstilbene acid were detected in SFE-CO₂ extracts by HPLC-DAD. In vitro antimicrobial activities of the extracts were evaluated against eight microbial strains (the bacteria Staphylococcus epidermidis, Staphylococcus aureus, Bacillus subtilis, Proteus vulgaris, Pseudomonas aeruginosa, Escherichia coli; and the fungi Aspergillus niger and Candida albicans). A marked inhibitory effect of the SFE extracts was observed against Staphylococcus epidermidis, Staphylococcus aureus and Bacillus subtilis. The IC(50) of SFE-CO₂ extracts ranged from 0.0557 mg/ml to 0.0689 mg/ml consisting of cancer (MCF-7 (0.0557 mg/ml)) as well as non-cancer (BHK-21 (0.0641 mg/ml), RAW264.7 (0.0689 mg/ml) and Vero (0.0625 mg/ml)) cells. Flow cytometry (FCM) was used to analyze death rate of the most sensitive strain (Staphylococcus aureus) caused by the SFE extracts. Additionally, the whole cell proteins of Staphylococcus aureus were analyzed by SDS-PAGE to detect if there were changes in protein patterns. In vivo antimicrobial activity was studies in mice that had been inoculated with Staphylococcus aureus. The potential mechanism of antimicrobial activity in vivo was studied by histopathology. Copyright © 2010 Elsevier GmbH. All rights reserved.

Supercritical fluid extraction (SFE) of ketamine metabolites from dried urine and on-line quantification by supercritical fluid chromatography and single mass detection (on-line SFE-SFC-MS).

PubMed

Hofstetter, Robert; Fassauer, Georg M; Link, Andreas

2018-02-15

On-line solid-phase supercritical fluid extraction (SFE) and chromatography (SFC) coupled to mass spectrometry (MS) has been evaluated for its usefulness with respect to metabolic profiling and pharmacological investigations of ketamine in humans. The aim of this study was to develop and validate a rapid, highly selective and sensitive SFE-SFC-MS method for the quantification of ketamine and its metabolites in miniature amounts in human urine excluding liquid-liquid extraction (LLE). Several conditions were optimized systematically following the requirements of the European Medicines Agency: selectivity, carry-over, calibration curve parameters (LLOQ, range and linearity), within- and between-run accuracy and precision, dilution integrity, matrix effect, and stability. The method, which required a relatively small volume of human urine (20 μL per sample), was validated for pharmacologically and toxicologically relevant concentrations ranging from 25.0 to 1000 ng/mL (r 2  > 0.995). The lower limit of quantification (LLOQ) for all compounds was found to be as low as 0.5 ng. In addition, stability of analytes during removal of water from the urine samples using different conditions (filter paper or ISOLUTE® HM-N) was studied. In conclusion, the method developed in this study can be successfully applied to studies of ketamine metabolites in humans, and may pave the way for routine application of on-line SFE-SFC-MS in clinical investigations. Copyright © 2018 Elsevier B.V. All rights reserved.

COMPARISONS OF SOXHLET EXTRACTION, PRESSURIZED LIQUID EXTRACTION, SUPERCRITICAL FLUID EXTRACTION, AND SUBCRITICAL WATER EXTRACTION FOR ENVIRONMENTAL SOLIDS: RECOVERY, SELECTIVITY, AND EFFECTS ON SAMPLE MATRIX. (R825394)

EPA Science Inventory

Extractions of a polycyclic aromatic hydrocarbon (PAH)-contaminated soil from a former manufactured gas plant site were performed with a Soxhlet apparatus (18 h), by pressurized liquid extraction (PLE) (50 min at 100°C), supercritical fluid extraction (SFE) (1 h at 150°...

Cytotoxic Activity of Kenaf Seed Oils from Supercritical Carbon Dioxide Fluid Extraction towards Human Colorectal Cancer (HT29) Cell Lines.

PubMed

Abd Ghafar, Siti Aisyah; Ismail, Maznah; Saiful Yazan, Latifah; Fakurazi, Sharida; Ismail, Norsharina; Chan, Kim Wei; Md Tahir, Paridah

2013-01-01

Kenaf (Hibiscus cannabinus) from the family Malvaceae, is a valuable fiber plant native to India and Africa and is currently planted as the fourth commercial crop in Malaysia. Kenaf seed oil contains alpha-linolenic acid, phytosterol such as β -sitosterol, vitamin E, and other antioxidants with chemopreventive properties. Kenaf seeds oil (KSO) was from supercritical carbon dioxide extraction fluid (SFE) at 9 different permutations of parameters based on range of pressures from 200 to 600 bars and temperature from 40 to 80°C. They were 200/40, 200/60, 200/80, 400/40, 400/60, 400/80, 600/40, 600/60, and 600/80. Extraction from 9 parameters of KSO-SFE was screened for cytotoxicity towards human colorectal cancer cell lines (HT29) and mouse embryonic fibroblast (NIH/3T3) cell lines using MTS assay. KSO-SFE at 600/40 showed the strongest cytotoxicity towards HT29 with IC50 of 200 µg/mL. The IC50 for NIH/3T3 was not detected even at highest concentration employed. Cell cycle analysis showed a significant increase in the accumulation of KSO-SFE-treated cells at sub-G1 phase, indicating the induction of apoptosis by KSO-SFE. Further apoptosis induction was confirmed by Annexin V/PI and AO/PI staining.

Cytotoxic Activity of Kenaf Seed Oils from Supercritical Carbon Dioxide Fluid Extraction towards Human Colorectal Cancer (HT29) Cell Lines

PubMed Central

Abd Ghafar, Siti Aisyah; Ismail, Maznah; Saiful Yazan, Latifah; Fakurazi, Sharida; Chan, Kim Wei; Md Tahir, Paridah

2013-01-01

Kenaf (Hibiscus cannabinus) from the family Malvaceae, is a valuable fiber plant native to India and Africa and is currently planted as the fourth commercial crop in Malaysia. Kenaf seed oil contains alpha-linolenic acid, phytosterol such as β-sitosterol, vitamin E, and other antioxidants with chemopreventive properties. Kenaf seeds oil (KSO) was from supercritical carbon dioxide extraction fluid (SFE) at 9 different permutations of parameters based on range of pressures from 200 to 600 bars and temperature from 40 to 80°C. They were 200/40, 200/60, 200/80, 400/40, 400/60, 400/80, 600/40, 600/60, and 600/80. Extraction from 9 parameters of KSO-SFE was screened for cytotoxicity towards human colorectal cancer cell lines (HT29) and mouse embryonic fibroblast (NIH/3T3) cell lines using MTS assay. KSO-SFE at 600/40 showed the strongest cytotoxicity towards HT29 with IC50 of 200 µg/mL. The IC50 for NIH/3T3 was not detected even at highest concentration employed. Cell cycle analysis showed a significant increase in the accumulation of KSO-SFE-treated cells at sub-G1 phase, indicating the induction of apoptosis by KSO-SFE. Further apoptosis induction was confirmed by Annexin V/PI and AO/PI staining. PMID:23606884

Comparative pharmacokinetics and bioavailability of four alkaloids in different formulations from Corydalis decumbens.

PubMed

Wu, Chunzhen; Yan, Renjie; Zhang, Rongjin; Bai, Fan; Yang, Yifang; Wu, Zhaoyang; Wu, Anming

2013-08-26

Corydalis decumbens, a Traditional Chinese Medicine listed in Chinese Pharmacopoeia, is clinically used for the treatment of paralytic stroke, headache, rheumatic arthritis and sciatica in China. This study was aimed to compare the pharmacokinetics and bioavailability of protopine, tetrahydropalmatine, bicuculline, and egenine in three formulations prepared from the rhizomes of Corydalis decumbens. Alkaloid extract (CDAs-SFE) was prepared from the rhizomes of Corydalis decumbens by supercritical CO2 fluid extraction; CDAs-SFE/HPβCD (hydroxypropyl-β-cyclodextrin inclusion complex), and CDAs-SFE/HCl (hydrochloride freeze-dried powder) were resulted from CDAs-SFE through complexation with HPβCD and hydrochloride, respectively. An UFLC-MS/MS method was developed for quantitative analysis of protopine, tetrahydropalmatine, bicuculline and egenine simultaneously in rat plasma after oral administration. The differences of pharmacokinetics and bioavailability of the four alkaloids in three formulations were determined by pharmacokinetics analyses. The Cmax, AUC and bioavailability of protopine and tetrahydropalamatine (bioactive components) in CDAs-SFE/HCl were significantly higher than in CDAs-SFE and in CDAs-SFE/HPβCD. In contrast, in CDAs-SFE/HPβCD, AUC and bioavailability of tetrahydropalamatine were significantly lower, while those of bicuculline (toxic compound) appeared to be higher than both in CDAs-SFE and in CDAs-SFE/HCl. The results indicated that CDAs-SFE/HCl was the best beneficial formulation among the three formulations for the alkaloid extract prepared from the rhizomes of Corydalis decumbens, in which protopine and tetrahydropalamatine displayed higher bioavailability, but lower for bicuculline. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Supercritical Fluid Extraction of Bioactive Compounds from Plant Materials.

PubMed

Wrona, Olga; Rafińska, Katarzyna; Możeński, Cezary; Buszewski, Bogusław

2017-11-01

There has been growing interest in the application of supercritical solvents over the last several years, many of the applications industrial in nature. The purpose of plant material extraction is to obtain large amounts of extract rich in the desired active compounds in a time-sensitive and cost-effective manner. The productivity and profitability of a supercritical fluid extraction (SFE) process largely depends on the selection of process parameters, which are elaborated upon in this paper. Carbon dioxide (CO2) is the most desirable solvent for the supercritical extraction of natural products. Its near-ambient critical temperature makes it suitable for the extraction of thermolabile components without degradation. A new approach has been adopted for SFE in which the solubility of nonpolar supercritical CO2 can be enhanced by the addition of small amounts of cosolvent.

EVALUATION OF ANALYTICAL METHODS FOR DETERMINING PESTICIDES IN BABY FOOD

EPA Science Inventory

Three extraction methods and two detection techniques for determining pesticides in baby food were evaluated. The extraction techniques examined were supercritical fluid extraction (SFE), enhanced solvent extraction (ESE), and solid phase extraction (SPE). The detection techni...

Inhibitory effect of rape pollen supercritical CO2 fluid extract against testosterone-induced benign prostatic hyperplasia in rats

PubMed Central

YANG, BI-CHENG; JIN, LI-LI; YANG, YI-FANG; LI, KUN; PENG, DAN-MING

2014-01-01

Benign prostatic hyperplasia (BPH) can lead to lower urinary tract symptoms. Rape pollen is an apicultural product that is composed of nutritionally valuable and biologically active substances. The aim of the present study was to investigate the protective effect of rape pollen supercritical CO2 fluid extract (SFE-CO2) in BPH development using a testosterone-induced BPH rat model. BPH was induced in the experimental groups by daily subcutaneous injections of testosterone for a period of 30 days. Rape pollen SFE-CO2 was administered daily by oral gavage concurrently with the testosterone injections. Animals were sacrificed at the scheduled termination and the prostates were weighed and subjected to histopathological examination. Testosterone, dihydrotestosterone (DHT), 5α-reductase and cyclooxygenase-2 (COX-2) levels were also measured. BPH-induced animals exhibited an increase in prostate weight with increased testosterone, DHT, 5α-reductase and COX-2 expression levels. However, rape pollen SFE-CO2 treatment resulted in significant reductions in the prostate index and testosterone, DHT, 5α-reductase and COX-2 levels compared with those in BPH-induced animals. Histopathological examination also demonstrated that rape pollen SFE-CO2 treatment suppressed testosterone-induced BPH. These observations indicate that rape pollen SFE-CO2 inhibits the development of BPH in rats and these effects are closely associated with reductions in DHT, 5α-reductase and COX-2 levels. Therefore, the results of the present study clearly indicate that rape pollen SFE-CO2 extract may be a useful agent in BPH treatment. PMID:24944593

Inhibitory effect of rape pollen supercritical CO2 fluid extract against testosterone-induced benign prostatic hyperplasia in rats.

PubMed

Yang, Bi-Cheng; Jin, Li-Li; Yang, Yi-Fang; Li, Kun; Peng, Dan-Ming

2014-07-01

Benign prostatic hyperplasia (BPH) can lead to lower urinary tract symptoms. Rape pollen is an apicultural product that is composed of nutritionally valuable and biologically active substances. The aim of the present study was to investigate the protective effect of rape pollen supercritical CO 2 fluid extract (SFE-CO 2 ) in BPH development using a testosterone-induced BPH rat model. BPH was induced in the experimental groups by daily subcutaneous injections of testosterone for a period of 30 days. Rape pollen SFE-CO 2 was administered daily by oral gavage concurrently with the testosterone injections. Animals were sacrificed at the scheduled termination and the prostates were weighed and subjected to histopathological examination. Testosterone, dihydrotestosterone (DHT), 5α-reductase and cyclooxygenase-2 (COX-2) levels were also measured. BPH-induced animals exhibited an increase in prostate weight with increased testosterone, DHT, 5α-reductase and COX-2 expression levels. However, rape pollen SFE-CO 2 treatment resulted in significant reductions in the prostate index and testosterone, DHT, 5α-reductase and COX-2 levels compared with those in BPH-induced animals. Histopathological examination also demonstrated that rape pollen SFE-CO 2 treatment suppressed testosterone-induced BPH. These observations indicate that rape pollen SFE-CO 2 inhibits the development of BPH in rats and these effects are closely associated with reductions in DHT, 5α-reductase and COX-2 levels. Therefore, the results of the present study clearly indicate that rape pollen SFE-CO 2 extract may be a useful agent in BPH treatment.

Supercritical Carbon Dioxide and Microwave-Assisted Extraction of Functional Lipophilic Compounds from Arthrospira platensis

PubMed Central

Esquivel-Hernández, Diego A.; López, Víctor H.; Rodríguez-Rodríguez, José; Alemán-Nava, Gibrán S.; Cuéllar-Bermúdez, Sara P.; Rostro-Alanis, Magdalena; Parra-Saldívar, Roberto

2016-01-01

Arthrospira platensis biomass was used in order to obtain functional lipophilic compounds through green extraction technologies such as supercritical carbon dioxide fluid extraction (SFE) and microwave-assisted extraction (MAE). The temperature (T) factor was evaluated for MAE, while for SFE, pressure (P), temperature (T), and co-solvent (ethanol) (CS) were evaluated. The maximum extraction yield of the obtained oleoresin was (4.07% ± 0.14%) and (4.27% ± 0.10%) for SFE and MAE, respectively. Extracts were characterized by gas chromatography mass spectrometry (GC-MS) and gas chromatography flame ionization detector (GC-FID). The maximum contents of functional lipophilic compounds in the SFE and MAE extracts were: for carotenoids 283 ± 0.10 μg/g and 629 ± 0.13 μg/g, respectively; for tocopherols 5.01 ± 0.05 μg/g and 2.46 ± 0.09 μg/g, respectively; and for fatty acids 34.76 ± 0.08 mg/g and 15.88 ± 0.06 mg/g, respectively. In conclusion, the SFE process at P 450 bar, T 60 °C and CS 53.33% of CO2 produced the highest yield of tocopherols, carotenoids and fatty acids. The MAE process at 400 W and 50 °C gives the best extracts in terms of tocopherols and carotenoids. For yield and fatty acids, the MAE process at 400 W and 70 °C produced the highest values. Both SFE and MAE showed to be suitable green extraction technologies for obtaining functional lipophilic compounds from Arthrospira platensis. PMID:27164081

Supercritical Carbon Dioxide and Microwave-Assisted Extraction of Functional Lipophilic Compounds from Arthrospira platensis.

PubMed

Esquivel-Hernández, Diego A; López, Víctor H; Rodríguez-Rodríguez, José; Alemán-Nava, Gibrán S; Cuéllar-Bermúdez, Sara P; Rostro-Alanis, Magdalena; Parra-Saldívar, Roberto

2016-05-05

Arthrospira platensis biomass was used in order to obtain functional lipophilic compounds through green extraction technologies such as supercritical carbon dioxide fluid extraction (SFE) and microwave-assisted extraction (MAE). The temperature (T) factor was evaluated for MAE, while for SFE, pressure (P), temperature (T), and co-solvent (ethanol) (CS) were evaluated. The maximum extraction yield of the obtained oleoresin was (4.07% ± 0.14%) and (4.27% ± 0.10%) for SFE and MAE, respectively. Extracts were characterized by gas chromatography mass spectrometry (GC-MS) and gas chromatography flame ionization detector (GC-FID). The maximum contents of functional lipophilic compounds in the SFE and MAE extracts were: for carotenoids 283 ± 0.10 μg/g and 629 ± 0.13 μg/g, respectively; for tocopherols 5.01 ± 0.05 μg/g and 2.46 ± 0.09 μg/g, respectively; and for fatty acids 34.76 ± 0.08 mg/g and 15.88 ± 0.06 mg/g, respectively. In conclusion, the SFE process at P 450 bar, T 60 °C and CS 53.33% of CO₂ produced the highest yield of tocopherols, carotenoids and fatty acids. The MAE process at 400 W and 50 °C gives the best extracts in terms of tocopherols and carotenoids. For yield and fatty acids, the MAE process at 400 W and 70 °C produced the highest values. Both SFE and MAE showed to be suitable green extraction technologies for obtaining functional lipophilic compounds from Arthrospira platensis.

Instrument for Solvent Extraction and Analysis (ISEE) of Organics from Regolith Simulant Using Supercritical Fluid Extraction and Chromatography

NASA Technical Reports Server (NTRS)

Franco, Carolina; Hintze, Paul E.

2017-01-01

ISEE is an instrument with the potential to perform extractions from regolith found on the surface of asteroids and planets, followed by characterization and quantitation of the extracts using supercritical fluid extraction (SFE) and chromatography (SFC). SFE is a developed technique proven to extract a wide range of organic compounds. SFC is similar to High Performance Liquid Chromatography (HPLC) but has the advantage of performing chiral separations without needing to derivatize the chiral compounds. CO2 will be the solvent for both stages as it is readily available in the Mars atmosphere. ISEE will capture CO2 from the environment, and use it for SFE and SFC. If successful, this would allow ISEE to perform analysis of organic compounds without using consumables. This paper will present results on a preliminary, proof-of-principle effort to use SFE and SFC to extract and analyze lunar regolith simulant spiked with organic compounds representing a range of organics that ISEE would expect to characterize. An optimization of variables for the extraction of the organics from the spiked regolith was successfully developed, using 138 bar pressure and 40 C temperature. The extraction flow rate was optimized at 2% SLPM with 30% methanol modifier. The extractions were successful with a value of 77.3+/- 0.9% of organics extracted. However, the recovery of organics after the extraction was very low with only 48.5+/-14.2%. Moreover, three columns were selected to analyze multiple samples at a time; two of them are Viridis HSS C18 SB and Torus DIOL, and the third column, specific for chiral separations, has not yet been selected yet.

Fatty acid profile and elemental content of avocado (Persea americana Mill.) oil--effect of extraction methods.

PubMed

Reddy, Mageshni; Moodley, Roshila; Jonnalagadda, Sreekanth B

2012-01-01

Interest in vegetable oil extracted from idioblast cells of avocado fruit is growing. In this study, five extraction methods to produce avocado oil have been compared: traditional solvent extraction using a Soxhlet or ultrasound, Soxhlet extraction combined with microwave or ultra-turrax treatment and supercritical fluid extraction (SFE). Traditional Soxhlet extraction produced the most reproducible results, 64.76 ± 0.24 g oil/100 g dry weight (DW) and 63.67 ± 0.20 g oil/100 g DW for Hass and Fuerte varieties, respectively. Microwave extraction gave the highest yield of oil (69.94%) from the Hass variety. Oils from microwave extraction had the highest fatty acid content; oils from SFE had wider range of fatty acids. Oils from Fuerte variety had a higher monounsaturated: saturated FA ratio (3.45-3.70). SFE and microwave extraction produced the best quality oil, better than traditional Soxhlet extraction, with the least amount of oxidizing metals present. Copyright © Taylor & Francis Group, LLC

Supercritical carbon dioxide extraction of capsaicinoids from malagueta pepper (Capsicum frutescens L.) assisted by ultrasound.

PubMed

Santos, Philipe; Aguiar, Ana C; Barbero, Gerardo F; Rezende, Camila A; Martínez, Julian

2015-01-01

Extracts from malagueta pepper (Capsicum frutescens L.) were obtained using supercritical fluid extraction (SFE) assisted by ultrasound, with carbon dioxide as solvent at 15MPa and 40°C. The SFE global yield increased up to 77% when ultrasound waves were applied, and the best condition of ultrasound-assisted extraction was ultrasound power of 360W applied during 60min. Four capsaicinoids were identified in the extracts and quantified by high performance liquid chromatography. The use of ultrasonic waves did not influence significantly the capsaicinoid profiles and the phenolic content of the extracts. However, ultrasound has enhanced the SFE rate. A model based on the broken and intact cell concept was adequate to represent the extraction kinetics and estimate the mass transfer coefficients, which were increased with ultrasound. Images obtained by field emission scanning electron microscopy showed that the action of ultrasonic waves did not cause cracks on the cell wall surface. On the other hand, ultrasound promoted disturbances in the vegetable matrix, leading to the release of extractable material on the solid surface. The effects of ultrasound were more significant on SFE from larger solid particles. Copyright © 2014 Elsevier B.V. All rights reserved.

The Effects of Different Extraction Methods on Antioxidant Properties, Chemical Composition, and Thermal Behavior of Black Seed (Nigella sativa L.) Oil

PubMed Central

Mohammed, Nameer Khairullah; Abd Manap, Mohd Yazid; Muhialdin, Belal J.; Alhelli, Amaal M.

2016-01-01

The Nigella sativa L. popularly referred to as black seeds are widely used as a form of traditional nutrition and medicine. N. sativa seeds were used for the extraction of their oil by way of supercritical fluid extraction (SFE) and cold press (CP) to determine the physicochemical properties, antioxidant activity, and thermal behavior. The GC-MS results showed the primary constituents in the Nigella sativa oil (NSO) were Caryophyllene (17.47%) followed by thymoquinone (TQ) (11.80%), 1,4-Cyclohexadiene (7.17%), longifolene (3.5%), and carvacrol (1.82%). The concentration of TQ was found to be 6.63 mg/mL for oil extracted using SFE and 1.56 mg/mL for oil extracted by CP method. The antioxidant activity measured by DPPH and the IC50 was 1.58 mg/mL and 2.30 mg/mL for SFE oil and cold pressed oil, respectively. The ferric reducing/antioxidant power (FRAP) activity for SFE oil and CP oil was 538.67 mmol/100 mL and 329.00 mmol/100 mL, respectively. The total phenolic content (TPC) of SFE oil was 160.51 mg/100 mL and 94.40 mg/100 mL for CP oil presented as gallic acid equivalents (GAE). This research showed that a high level of natural antioxidants could be derived from NSO extracted by SFE. PMID:27642353

The Effects of Different Extraction Methods on Antioxidant Properties, Chemical Composition, and Thermal Behavior of Black Seed (Nigella sativa L.) Oil.

PubMed

Mohammed, Nameer Khairullah; Abd Manap, Mohd Yazid; Tan, Chin Ping; Muhialdin, Belal J; Alhelli, Amaal M; Meor Hussin, Anis Shobirin

2016-01-01

The Nigella sativa L. popularly referred to as black seeds are widely used as a form of traditional nutrition and medicine. N. sativa seeds were used for the extraction of their oil by way of supercritical fluid extraction (SFE) and cold press (CP) to determine the physicochemical properties, antioxidant activity, and thermal behavior. The GC-MS results showed the primary constituents in the Nigella sativa oil (NSO) were Caryophyllene (17.47%) followed by thymoquinone (TQ) (11.80%), 1,4-Cyclohexadiene (7.17%), longifolene (3.5%), and carvacrol (1.82%). The concentration of TQ was found to be 6.63 mg/mL for oil extracted using SFE and 1.56 mg/mL for oil extracted by CP method. The antioxidant activity measured by DPPH and the IC50 was 1.58 mg/mL and 2.30 mg/mL for SFE oil and cold pressed oil, respectively. The ferric reducing/antioxidant power (FRAP) activity for SFE oil and CP oil was 538.67 mmol/100 mL and 329.00 mmol/100 mL, respectively. The total phenolic content (TPC) of SFE oil was 160.51 mg/100 mL and 94.40 mg/100 mL for CP oil presented as gallic acid equivalents (GAE). This research showed that a high level of natural antioxidants could be derived from NSO extracted by SFE.

Supercritical Fluid Extraction of Bacterial and Archaeal Lipid Biomarkers from Anaerobically Digested Sludge

PubMed Central

Hanif, Muhammad; Atsuta, Yoichi; Fujie, Koichi; Daimon, Hiroyuki

2012-01-01

Supercritical fluid extraction (SFE) was used in the analysis of bacterial respiratory quinone (RQ), bacterial phospholipid fatty acid (PLFA), and archaeal phospholipid ether lipid (PLEL) from anaerobically digested sludge. Bacterial RQ were determined using ultra performance liquid chromatography (UPLC). Determination of bacterial PLFA and archaeal PLEL was simultaneously performed using gas chromatography-mass spectrometry (GC-MS). The effects of pressure, temperature, and modifier concentration on the total amounts of RQ, PLFA, and PLEL were investigated by 23 experiments with five settings chosen for each variable. The optimal extraction conditions that were obtained through a multiple-response optimization included a pressure of 23.6 MPa, temperature of 77.6 °C, and 10.6% (v/v) of methanol as the modifier. Thirty nine components of microbial lipid biomarkers were identified in the anaerobically digested sludge. Overall, the SFE method proved to be more effective, rapid, and quantitative for simultaneously extracting bacterial and archaeal lipid biomarkers, compared to conventional organic solvent extraction. This work shows the potential application of SFE as a routine method for the comprehensive analysis of microbial community structures in environmental assessments using the lipid biomarkers profile. PMID:22489140

Supercritical fluid extraction of selected pharmaceuticals from water and serum.

PubMed

Simmons, B R; Stewart, J T

1997-01-24

Selected drugs from benzodiazepine, anabolic agent and non-steroidal anti-inflammatory drug (NSAID) therapeutic classes were extracted from water and serum using a supercritical CO2 mobile phase. The samples were extracted at a pump pressure of 329 MPa, an extraction chamber temperature of 45 degrees C, and a restrictor temperature of 60 degrees C. The static extraction time for all samples was 2.5 min and the dynamic extraction time ranged from 5 to 20 min. The analytes were collected in appropriate solvent traps and assayed by modified literature HPLC procedures. Analyte recoveries were calculated based on peak height measurements of extracted vs. unextracted analyte. The recovery of the benzodiazepines ranged from 80 to 98% in water and from 75 to 94% in serum. Anabolic drug recoveries from water and serum ranged from 67 to 100% and 70 to 100%, respectively. The NSAIDs were recovered from water in the 76 to 97% range and in the 76 to 100% range from serum. Accuracy, precision and endogenous peak interference, if any, were determined for blank and spiked serum extractions and compared with classical sample preparation techniques of liquid-liquid and solid-phase extraction reported in the literature. For the benzodiazepines, accuracy and precision for supercritical fluid extraction (SFE) ranged from 1.95 to 3.31 and 0.57 to 1.25%, respectively (n = 3). The SFE accuracy and precision data for the anabolic agents ranged from 4.03 to 7.84 and 0.66 to 2.78%, respectively (n = 3). The accuracy and precision data reported for the SFE of the NSAIDs ranged from 2.79 to 3.79 and 0.33 to 1.27%, respectively (n = 3). The precision of the SFE method from serum was shown to be comparable to the precision obtained with other classical preparation techniques.

Antifungal response of oral-associated candidal reference strains (American Type Culture Collection) by supercritical fluid extract of nutmeg seeds for geriatric denture wearers: An in vitro screening study.

PubMed

Iyer, Meenakshi; Gujjari, Anil Kumar; Gowda, Vishakante; Angadi, Shridhar

2017-01-01

Since time immemorial, plants have continued to play a predominant role in the maintenance of human health as sources of medicinal compounds. Several effective antifungal agents are available for oral Candida infections; the failure is not uncommon because isolates of Candida albicans may exhibit resistance to the drug during therapy. The present study aimed to identify an alternative, inexpensive, simple, and effective method of preventing and controlling the candidal infection. All the procured and authenticated nutmeg seeds were dried in shade and cleaned by hand sorting. The crushed seeds were passed through mesh no. 40 individually. About 50 g of powdered nutmeg seeds was loaded in the supercritical fluid extractor unit using supercritical CO 2 as extracting solvent in accordance with the methods of Nguyen et al . Supercritical fluid (SFE) extraction was done using CO 2 gas without any cosolvents. The nutmeg extract displayed antifungal activity with the effective zone of inhibition ranging from 18.0 to 12.0 mm when compared with nystatin as positive control. This paper described the in vitro antibacterial activity, and phytochemical analysis of SFE extract of nutmeg ( Myristica fragrans ) evaluated against C. albicans (American Type Culture Collection 10231) through agar well diffusion method. SFE of nutmeg seeds can be used as an adjunct to conventional therapy for oral candidiasis.

Antioxidant Properties of Essential Oil Extracted from Pinus morrisonicola Hay Needles by Supercritical Fluid and Identification of Possible Active Compounds by GC/MS.

PubMed

Cheng, Ming-Ching; Chang, Wen-Hua; Chen, Chih-Wei; Li, Wen-Wing; Tseng, Chin-Yin; Song, Tuzz-Ying

2015-10-20

Pine (Pinus morrisonicola Hay, PM) needles have been used as folk medicine for their antihypertension and lipid-lowering effects. As supercritical fluid extraction (SFE) is considered an ideal technique for the extraction of essential oil from plant materials, the present work investigated the optimal SFE conditions and the protective effects of different resulting fractions of PM needles on lipid peroxidation and foam cell production in macrophages. Nine PM needle extracts (PME1-9) were obtained in 1%-4% yields using different SFE conditions, of which PME1 had the lowest yield (1.1%) and PME3 the highest (3.9%). PME3 exhibited lower cytotoxic effects and stronger inhibition of lipid peroxidation and formation of foam cell in RAW 264.7 macrophages than those of other PME extracts. PME3-1 purified from PME3 by column and thin layer chromatography inhibited LDL oxidation more effectively than did PME3 in a cell-free system oxidized by Cu(2+). PME3-1 dose-dependently (25-100 μg/mL) decreased conjugated diene levels and foam cell formation induced by ox-LDL. GC/MS analyses revealed that 1-docosene, neophytadiene, and methyl abietate were increased 5.2-, 1.7- and 4.3-fold in PME3-1 relative to PME3. A new hydrocarbon compound, cedrane-8,13-diol, was identified in PME3-1. Overall, the present study demonstrates the optimal extraction conditions of SFE of PM and identifies the most potent antioxidant fractions and possible active compounds in PM.

Role of modifiers for analytical-scale supercritical fluid extraction of environmental samples

DOE Office of Scientific and Technical Information (OSTI.GOV)

Langenfeld, J.J.; Hawthorne, S.B.; Miller, D.J.

1994-03-15

Supercritical fluid extraction (SFE) using eight different CO[sub 2] + organic modifier mixtures and one ternary mixture (CO[sub 2] + methanol/toluene) at two different concentrations (1 and 10% v/v) was performed on two certified reference materials including polychlorinated biphenyls (PCBs) from river sediment and polycyclic aromatic hydrocarbons (PAHs) from urban air particulate matter. The modifier identity was more important than modifier concentration for increasing extraction efficiencies. Acidic/basic modifiers including methanol, acetic acid, and aniline greatly enhanced the extraction of PCBs. Low molecular weight PAHs were best extracted with modifiers including aniline, acetic acid, acetonitrile, methanol/toluene, hexane, and diethylamine. In contrast,more » modifiers capable of dipole-induced dipole interactions and [pi]-[pi] interactions such as toluene, diethylamine, and methylene chloride were the best modifiers to use for SFE of high molecular weight PAHs from air particulates. 37 refs., 6 tabs.« less

Study of sulfur bonding on gallium arsenide (100) surfaces using supercritical fluid extraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cabauy, P.; Darici, Y.; Furton, K.G.

1995-12-01

In the last decades Gallium Arsenide (GaAs) has been considered the semiconductor that will replace silicon because of its direct band gap and high electron mobility. Problems with GaAs Fermi level pinning has halted its widespread use in the electronics industry. The formation of oxides on GaAs results in a high density of surface states that effectively pin the surface Fermi level at the midgap. Studies on sulfur passivation have eliminated oxidation and virtually unpinned the Fermi level on the GaAs surface. This has given rise to interest in sulfur-GaAs bonds. In this presentation, we will discuss the types ofmore » sulfur bonds extracted from a sulfur passivated GaAs (100) using Supercritical Fluid (CO2) Extraction (SFE). SFE can be a valuable tool in the study of chemical speciations on semiconductor surfaces. The variables evaluated to effectively study the sulfur species from the GaAs surface include passivation techniques, supercritical fluid temperatures, densities, and extraction times.« less

Nitrous Oxide Explosive Hazards

DTIC Science & Technology

2008-05-01

Supercritical Fluid Extraction- Capillary Gas Chromatography (SFE-GC) With a Conventional Split/Splitless Injection Port”, Journal of Chromatographic...Aromatic Hydrocarbons from Environmental Solids Using Supercritical Fluids ”, Steven B. Hawthorne and David J. Miller, Anal. Chem. 59, pp 1705-1708, 1987...Katayama, T., J. Supercrit . Fluids , 1990, 3, 78-84. 30. “ Supercritical Fluid Extraction of Fungal Oil Using CO2, N2O, CHF3, and SF6”, Keiji Sakaki

Fractionation and Purification of Bioactive Compounds Obtained from a Brewery Waste Stream

PubMed Central

Barbosa-Pereira, Letricia; Pocheville, Ainara; Angulo, Inmaculada; Paseiro-Losada, Perfecto; Cruz, Jose M.

2013-01-01

The brewery industry generates waste that could be used to yield a natural extract containing bioactive phenolic compounds. We compared two methods of purifying the crude extract—solid-phase extraction (SPE) and supercritical fluid extraction (SFE)—with the aim of improving the quality of the final extract for potential use as safe food additive, functional food ingredient, or nutraceutical. The predominant fractions yielded by SPE were the most active, and the fraction eluted with 30% (v/v) of methanol displayed the highest antioxidant activity (0.20 g L−1), similar to that of BHA. The most active fraction yielded by SFE (EC50 of 0.23 g L−1) was obtained under the following conditions: temperature 40°C, pressure 140 bar, extraction time 30 minutes, ethanol (6%) as a modifier, and modifier flow 0.2 mL min−1. Finally, we found that SFE is the most suitable procedure for purifying the crude extracts and improves the organoleptic characteristics of the product: the final extract was odourless, did not contain solvent residues, and was not strongly coloured. Therefore, natural extracts obtained from the residual stream and purified by SFE can be used as natural antioxidants with potential applications in the food, cosmetic, and pharmaceutical industries. PMID:23762844

Development of an automated method for determining oil in water by direct aqueous supercritical fluid extraction coupled on-line with infrared spectroscopy.

PubMed

Minty, B; Ramsey, E D; Davies, I

2000-12-01

A direct aqueous supercritical fluid extraction (SFE) system was developed which can be directly interfaced to an infrared spectrometer for the determination of oil in water. The technique is designed to provide an environmentally clean, automated alternative to established IR methods for oil in water analysis which require the use of restricted organic solvents. The SFE-FTIR method involves minimum sample handling stages, with on-line analysis of a 500 ml water sample being complete within 15 min. Method accuracy for determining water samples spiked with gasoline, white spirit, kerosene, diesel or engine oil was 81-100% with precision (RSD) ranging from 3 to 17%. An independent evaluation determined a 2 ppm limit of quantification for diesel in industrial effluents. The results of a comparative study involving an established IR method and the SFE-FTIR method indicate that oil levels calculated using an accepted equation which includes coefficients derived from reference hydrocarbon standards may result in significant errors. A new approach permitted the derivation of quantification coefficients for the SFE-FTIR analyses which provided improved results. In situations where the identity of the oil to be analysed is known, a rapid off-line SFE-FTIR system calibration procedure was developed and successfully applied to various oils. An optional in-line silica gel clean-up procedure incorporated within the SFE-FTIR system enables the same water sample to be analysed for total oil content including vegetable oils and selectively for petroleum oil content within a total of 20 min. At the end of an analysis the SFE system is cleaned using an in situ 3 min clean cycle.

Optimisation of the supercritical extraction of toxic elements in fish oil.

PubMed

Hajeb, P; Jinap, S; Shakibazadeh, Sh; Afsah-Hejri, L; Mohebbi, G H; Zaidul, I S M

2014-01-01

This study aims to optimise the operating conditions for the supercritical fluid extraction (SFE) of toxic elements from fish oil. The SFE operating parameters of pressure, temperature, CO2 flow rate and extraction time were optimised using a central composite design (CCD) of response surface methodology (RSM). High coefficients of determination (R²) (0.897-0.988) for the predicted response surface models confirmed a satisfactory adjustment of the polynomial regression models with the operation conditions. The results showed that the linear and quadratic terms of pressure and temperature were the most significant (p < 0.05) variables affecting the overall responses. The optimum conditions for the simultaneous elimination of toxic elements comprised a pressure of 61 MPa, a temperature of 39.8ºC, a CO₂ flow rate of 3.7 ml min⁻¹ and an extraction time of 4 h. These optimised SFE conditions were able to produce fish oil with the contents of lead, cadmium, arsenic and mercury reduced by up to 98.3%, 96.1%, 94.9% and 93.7%, respectively. The fish oil extracted under the optimised SFE operating conditions was of good quality in terms of its fatty acid constituents.

Chemical Constituents of Supercritical Extracts from Alpinia officinarum and the Feeding Deterrent Activity against Tribolium castaneum.

PubMed

Xin, Mintong; Guo, Shanshan; Zhang, Wenjuan; Geng, Zhufeng; Liang, Junyu; Du, Shushan; Deng, Zhiwei; Wang, Yongyan

2017-04-18

Alpinia officinarum has been confirmed to possess bioactivities against some pests. In this work, a sample was obtained from A. officinarum rhizomes by supercritical fluid CO₂ extraction (SFE). According to GC-MS analysis, the main chemical components for SFE-sample included benzylacetone (26.77%), 1,7-diphenyl-5-hydroxy-3-heptanone (17.78%), guaiacylacetone (10.03%) and benzenepropanal (7.42%). The essential oil of A. officinarum rhizomes (LD 50 = 20.71 μg/adult) exhibited more contact toxicity than SFE extract (LD 50 = 82.72 μg/adult) against Tribolium castaneum . From SFE extracts, one new compound, 1-phenyl-4-(16,17-dimethyl-9,13-octadiene)-5-isopentenyl-7-(4"-methoxyl-3"-hydroxyl-phenyl)-3-heptanone ( 3 ), together with five known compounds identified as 5-hydroxy-1,7-diphenyl-3-heptanone ( 1 ), 1,7-diphenyl-4-hepten-3-one ( 2 ), galangin ( 4 ), galangin-3-methyl ether ( 5 ) and pinocembrin ( 6 ), were isolated and their feeding deterrent activities against T. castaneum adults were assessed. It was found that compounds 1 - 6 had feeding deterrent activities against T. castaneum with feeding deterrent indices of 18.21%, 18.94%, 19.79%, 26.99%, 20.34%, and 35.81%, respectively, at the concentration of 1500 ppm. Hence, the essential oil and SFE extracts/compounds of A. officinarum rhizomes represent promising alternatives in the control of T. castaneum adults.

Combined analysis by GC (RI), GC-MS and 13C NMR of the supercritical fluid extract of Abies alba twigs.

PubMed

Duquesnoy, Emilie; Marongiu, Bruno; Castola, Vincent; Piras, Alessandra; Porcedda, Silvia; Casanova, Joseph

2010-12-01

Two samples (leaves and twigs) of Abies alba Miller from Corsica were extracted using supercritical CO2 and their chemical compositions were compared with those of the essential oils obtained from the same batch of plant material. In total 45 components were identified using combined analysis by GC (RI), GC-MS and 13C NMR. It was observed that the contents of monoterpenes (mainly represented by limonene, alpha-pinene and camphene) were significantly lower in the supercritical fluid extract (SFE) than in the essential oil (EO). Conversely, the proportions of sesquiterpenes were much higher in CO2 extracts than in essential oils (around 30% vs 4%). Cis-abienol, a diterpene alcohol, was identified only in SFE, and the proportions of this constituent (7.5% and 17.3%) were determined using quantitative 13C NMR since it was under estimated using the standard conditions of GC.

Supercritical CO₂ extraction of volatile oils from Sardinian Foeniculum vulgare ssp. vulgare (Apiaceae): chemical composition and biological activity.

PubMed

Piras, Alessandra; Falconieri, Danilo; Porcedda, Silvia; Marongiu, Bruno; Gonçalves, Maria José; Cavaleiro, Carlos; Salgueiro, Ligia

2014-01-01

This article reports the results on the composition and antifungal effect of volatile extracts obtained from the aerial parts of Sardinian wild fennel (Foeniculum vulgare Mill.), by supercritical fluid extraction (SFE) and by hydrodistillation (HD). The extracts were analysed by gas chromatography-mass spectrometry for qualitative composition and gas chromatography-flame ionisation detector to establish the percentage of constituents. The main components were fenchone (7.1% vs. 8.8%), estragole (34.9% vs. 42.6%) and (E)-anethole (24.6% vs. 43.4%) in the SFE and HD extract, respectively. Minimum inhibitory concentrations (MICs) were measured according to the reference Clinical and Laboratory Standards Institute (CLSI) broth macrodilution protocols. Minimum lethal concentrations were determined by subsequent subculturing of the same cell suspensions in solid medium. The essential oil was more active against Candida albicans, whereas the supercritical fluid extract possesses higher activity against Candida guillermondii and Cryptococcus neoformans, with MIC values of 0.32 μL/mL.

Supercritical fluid extraction of grape seeds: extract chemical composition, antioxidant activity and inhibition of nitrite production in LPS-stimulated Raw 264.7 cells.

PubMed

Pérez, Concepción; Ruiz del Castillo, María Luisa; Gil, Carmen; Blanch, Gracia Patricia; Flores, Gema

2015-08-01

Grape by-products are a rich source of bioactive compounds having broad medicinal properties, but are usually wasted from juice/wine processing industries. The present study investigates the use of supercritical fluid extraction (SFE) for obtaining an extract rich in bioactive compounds. First, some variables involved in the extraction were applied. SFE conditions were selected based on the oil mass yield, fatty acid profile and total phenolic composition. As a result, 40 °C and 300 bar were selected as operational conditions. The phenolic composition of the grape seed oil was determined using LC-DAD. The antioxidant activity was determined by ABTS and DPPH assays. For the anti-inflammatory activity the inhibition of nitrite production was assessed. The grape seed oil extracted was rich in phenolic compounds and fatty acids with significant antioxidant and anti-inflammatory activities. From these results, added economic value to this agroindustrial residue is proposed using environmentally friendly techniques.

Analysis of the essential oils of Alpiniae Officinarum Hance in different extraction methods

NASA Astrophysics Data System (ADS)

Yuan, Y.; Lin, L. J.; Huang, X. B.; Li, J. H.

2017-09-01

It was developed for the analysis of the essential oils of Alpiniae Officinarum Hance extracted by steam distillation (SD), ultrasonic assisted solvent extraction (UAE) and supercritical fluid extraction (SFE) via gas chromatography mass spectrometry (GC-MS) combined with retention index (RI) method. There were multiple volatile components of the oils extracted by the three above-mention methods respectively identified; meanwhile, each one was quantified by area normalization method. The results indicated that the content of 1,8-Cineole, the index constituent, by SD was similar as SFE, and higher than UAE. Although UAE was less time consuming and consumed less energy, the oil quality was poorer due to the use of organic solvents was hard to degrade. In addition, some constituents could be obtained by SFE but could not by SD. In conclusion, essential oil of different extraction methods from the same batch of materials had been proved broadly similarly, however, there were some differences in composition and component ratio. Therefore, development and utilization of different extraction methods must be selected according to the functional requirements of products.

Chemical Composition Analysis of Extracts from Ficus Hirta Using Supercritical Fluid

NASA Astrophysics Data System (ADS)

Deng, S. B.; Chen, J. P.; Chen, Y. Z.; Yu, C. Q.; Yang, Y.; Wu, S. H.; Chen, C. Z.

2018-05-01

Ficus hirta was extracted by supercritical carbon dioxide. The volatile chemical components of extracts were analyzed using gas chromatography-mass spectrometry (GC-MS). The percentage of products extracted by Supercritical Fluid Extraction(SFE) was 2.5%. Nineteen volatile compounds were identified. The main volatile components were Elemicin, Psoralen, Palmitic acid, Bergapten, α-Linolenic acid, Medicarpin, Retinoic Acid, Maackiain, and Squalene. The method is simple and quick, and can be used for the preliminary analysis of chemical constituents of supercritical extracts of Ficus hirta.

Economic Analysis of an Integrated Annatto Seeds-Sugarcane Biorefinery Using Supercritical CO2 Extraction as a First Step

PubMed Central

Albarelli, Juliana Q.; Santos, Diego T.; Cocero, María José; Meireles, M. Angela A.

2016-01-01

Recently, supercritical fluid extraction (SFE) has been indicated to be utilized as part of a biorefinery, rather than as a stand-alone technology, since besides extracting added value compounds selectively it has been shown to have a positive effect on the downstream processing of biomass. To this extent, this work evaluates economically the encouraging experimental results regarding the use of SFE during annatto seeds valorization. Additionally, other features were discussed such as the benefits of enhancing the bioactive compounds concentration through physical processes and of integrating the proposed annatto seeds biorefinery to a hypothetical sugarcane biorefinery, which produces its essential inputs, e.g., CO2, ethanol, heat and electricity. For this, first, different configurations were modeled and simulated using the commercial simulator Aspen Plus® to determine the mass and energy balances. Next, each configuration was economically assessed using MATLAB. SFE proved to be decisive to the economic feasibility of the proposed annatto seeds-sugarcane biorefinery concept. SFE pretreatment associated with sequential fine particles separation process enabled higher bixin-rich extract production using low-pressure solvent extraction method employing ethanol, meanwhile tocotrienols-rich extract is obtained as a first product. Nevertheless, the economic evaluation showed that increasing tocotrienols-rich extract production has a more pronounced positive impact on the economic viability of the concept. PMID:28773616

Supercritical CO₂ extract and essential oil of aerial part of Ledum palustre L.--Chemical composition and anti-inflammatory activity.

PubMed

Baananou, Sameh; Bagdonaite, Edita; Marongiu, Bruno; Piras, Alessandra; Porcedda, Silvia; Falconieri, Danilo; Boughattas, Naceur A

2015-01-01

The anti-inflammatory activity of two extracts from the aerial parts of Ledum palustre has been reported. The volatile oil was obtained by supercritical fluid extraction (SFE) and the essential oil by hydrodistillation (HD). The oils were analysed by gas chromatography-mass spectrometry to monitor their composition. Both extracts shared as main compound (41.0-43.4%) ledol (23.3-26.7%) and ascaridole (15.1-4.5%). The anti-inflammatory activity was evaluated by the subcutaneous carrageenan injection-induced hind paw oedema. The treated animals received essential oil (SFE and HD), the reference group received ketoprofen or piroxicam and the control group received NaCl 0.9%. A statistical analysis was performed by the Student t-test. The results show that L. palustre essential oil enhanced a significant inhibition of oedema (50-73%) for HD oil and (52-80%) for SFE oil. These results were similar to those obtained with piroxicam (70%) and ketoprofen (55%).

Chemical composition and antioxidant activity of Lippia alba essential oil obtained by supercritical CO2 and hydrodistillation

USDA-ARS?s Scientific Manuscript database

Lippia alba extracts from Mexico were obtained by hydrodistillation (HD) and supercritical fluid (SFE) extraction methods. The extracts were analyzed by gas chromatography using flame ionization and mass spectrometric detections. Antioxidant activity was tested by two methods (DPPH and ABTS) and tot...

Combining supercritical fluid extraction of soil herbicides with enzyme immunoassay analysis.

PubMed

Stearman, G K

2001-10-01

Supercritical fluid extraction (SFE) of soil herbicides followed by enzyme immunoassay analysis (EIA) is explained in a step-by-step process. Extracted herbicides, include 2,4-D, simazine, atrazine, and alachlor. The herbicide, trifluralin was not successfully analyzed by EIA because of crossreacting metabolites. Problems with SFE, including uneven packing of cells, leaks, uneven flow and clogging, can largely be eliminated as the method parameters are optimized. It was necessary to add modifiers including methanol or acetone to the SF CO2 to increase the solubility of the analytes. Detection limits of 2.5 ng/g soil for atrazine and alachlor and 15 ng/g soil for simazine and 2,4-D without concentration of the sample were achieved. Recoveries above 80% and relative standard deviations (RSDs) less than 15% for 2,4-D simazine, atrazine and alachlor were achieved. Atrazine and alachlor recoveries were above 90% with RSDs below 10%. Forty soil samples could be extracted and analyzed in an 8-h day.

Phenolic Extracts from Wild Olive Leaves and Their Potential as Edible Oils Antioxidants

PubMed Central

Lafka, Theodora-Ioanna; Lazou, Andriana E.; Sinanoglou, Vassilia J.; Lazos, Evangelos S.

2013-01-01

The kinetics solid-liquid extraction of phenolics from wild olive leaves was elaborated using different mathematical models (Peleg, second order, Elovich, and power law model). As solvents, methanol, ethanol, ethanol:water 1:1, n-propanol, isopropanol and ethyl acetate were used. The second order model best described the solvent extraction process, followed by the Elovich model. The most effective solvent was ethanol with optimum phenol extraction conditions 180 min, solvent to sample ratio 5:1 v/w and pH 2. Ethanol extract exhibited the highest antiradical activity among solvent and supercritical fluid extraction (SFE) extracts, which in addition showed the highest antioxidant capacity compared to synthetic and natural food antioxidants such as BHT, ascorbyl palmitate and vitamin E. Antioxidant potential of SFE extract was quite high, although its phenolic potential was not. Leaf extracts were proven to be good protectors for olive and sunflower oils at levels of 150 ppm. PMID:28239093

Feasibility of ion-pair/supercritical fluid extraction of an ionic compound--pseudoephedrine hydrochloride.

PubMed

Eckard, P R; Taylor, L T

1997-02-01

The supercritical fluid extraction (SFE) of an ionic compound, pseudoephedrine hydrochloride, from a spiked-sand surface was successfully demonstrated. The effect of carbon dioxide density (CO2), supercritical fluid composition (pure vs. methanol modified), and the addition of a commonly used reversed-phase liquid chromatographic ion-pairing reagent, 1-heptanesulfonic acid, sodium salt, on extraction efficiency was examined. The extraction recoveries of pseudoephedrine hydrochloride with the addition of the ion-pairing reagent from a spiked-sand surface were shown to be statistically greater than the extraction recoveries without the ion-pairing reagent with both pure and methanol-modified carbon dioxide.

Free-radical scavenging activity and antibacterial impact of Greek oregano isolates obtained by SFE.

PubMed

Stamenic, Marko; Vulic, Jelena; Djilas, Sonja; Misic, Dusan; Tadic, Vanja; Petrovic, Slobodan; Zizovic, Irena

2014-12-15

The antioxidant and antibacterial properties of Greek oregano extracts obtained by fractional supercritical fluid extraction (SFE) with carbon dioxide were investigated and compared with the properties of essential oil obtained by hydrodistillation. According to DPPH, hydroxyl radical and superoxide anion radical scavenging activity assays, the supercritical extracts expressed stronger antioxidant activity comparing to the essential oil. The most effective was the supercritical extract obtained by fractional extraction at 30 MPa and 100°C after the volatile fraction had been extracted at lower pressure. At the same time this extract showed strong antibacterial activity against staphylococci, including MRSA strain, but did not affect Escherichia coli of normal intestinal flora. The essential oil obtained by hydrodistillation showed stronger antibacterial activity against E. coli, Salmonella and Klebsiella pneumoniae, comparing to the supercritical extracts but at the same affected the normal gut flora. Copyright © 2014 Elsevier Ltd. All rights reserved.

Supercritical Fluid Extraction of Eucalyptus globulus Bark—A Promising Approach for Triterpenoid Production

PubMed Central

Domingues, Rui M. A.; Oliveira, Eduardo L. G.; Freire, Carmen S. R.; Couto, Ricardo M.; Simões, Pedro C.; Neto, Carlos P.; Silvestre, Armando J. D.; Silva, Carlos M.

2012-01-01

Eucalyptus bark contains significant amounts of triterpenoids with demonstrated bioactivity, namely triterpenic acids and their acetyl derivatives (ursolic, betulinic, oleanolic, betulonic, 3-acetylursolic, and 3-acetyloleanolic acids). In this work, the supercritical fluid extraction (SFE) of Eucalyptus globulus deciduous bark was carried out with pure and modified carbon dioxide to recover this fraction, and the results were compared with those obtained by Soxhlet extraction with dichloromethane. The effects of pressure (100–200 bar), co-solvent (ethanol) content (0, 5 and 8% wt), and multistep operation were studied in order to evaluate the applicability of SFE for their selective and efficient production. The individual extraction curves of the main families of compounds were measured, and the extracts analyzed by GC-MS. Results pointed out the influence of pressure and the important role played by the co-solvent. Ethanol can be used with advantage, since its effect is more important than increasing pressure by several tens of bar. At 160 bar and 40 °C, the introduction of 8% (wt) of ethanol greatly improves the yield of triterpenoids more than threefold. PMID:22837719

Fatty acid composition of seed oil from Fremontodendron californicum

USDA-ARS?s Scientific Manuscript database

The fatty acid composition of the low water-use shrub Fremontodendron californicum was examined by high temperature capillary gas chromatography. The ground seeds were extracted by supercritical fluid extraction (SFE) to obtain the oil (25.6% w/w) and for subsequent determination of the fatty acid c...

IN VIVO STUDIES AND STABILITY STUDY OF CLADOPHORA GLOMERATA EXTRACT AS A COSMETIC ACTIVE INGREDIENT.

PubMed

Fabrowska, Joanna; Kapuscinska, Alicja; Leska, Boguslawa; Feliksik-Skrobich, Katarzyna; Nowak, Izabela

2017-03-01

Marine algae are widely used as cosmetics raw materials. Likewise, freshwater alga Cladophora glomerata may be a good source of fatty acids and others bioactive agents. The aims of this study was to find out if the addition of the extract from the freshwater C. glonerata affects the stability of prepared cosmetic emulsions and to investigate in vivo effects of the extract in cosmetic formulations on hydration and elasticity of human skin. Extract from the freshwater C. glonierata was obtained using supercritical fluid extraction (SFE). Two forms of O/W emulsions were prepared: placebo and emulsion containing 0.5% of Cladophora SFE extract. The stability of obtained emulsions was investigated by using Turbiscan Lab Expert. Emulsions were applied by .volunteers daily. Corneometer was used to evaluate skin hydration and cutometer to examine skin elasticity. Measurements were conducted at reference point (week 0) and after 1st, 2nd, 3rd and 4th week of application. The addition of Cladophora extract insignificantly affected stability of the emulsion. The extract from C. glomerata in the emulsion influenced the improvement of both skin hydration and its elasticity. Thus, freshwater C. glonierata extract prepared via SFE method may be considered as an effective cosmetic raw material used as a moisturizing and firming agent.

Removal of polycyclic aromatic hydrocarbons from soil: a comparison between bioremoval and supercritical fluids extraction.

PubMed

Amezcua-Allieri, M A; Ávila-Chávez, M A; Trejo, A; Meléndez-Estrada, J

2012-03-01

Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic substances which are resistant to environmental degradation due to their highly hydrophobic nature. Soils contaminated with PAHs pose potential risks to human and ecological health, therefore concern over their adverse effects have resulted in extensive studies on their removal from contaminated soils. The main purpose of this study was to compare experimental results of PAHs removal, from a natural certified soil polluted with PAHs, by biological methods (using bioaugmentation and biostimulation in a solid-state culture) with those from supercritical fluid extraction (SFE), using supercritical ethane as solvent. The comparison of results between the two methods showed that maximal removal of naphthalene, acenaphthene, fluorene, and chrysene was performed using bioremediation; however, for the rest of the PAHs considered (fluoranthene, pyrene, and benz(a)anthracene) SFE resulted more efficient. Although bioremediation achieved higher removal ratios for certain hydrocarbons and takes advantage of the increased rate of natural biological processes, it takes longer time (i.e. 36 d vs. half an hour) than SFE and it is best for 2-3 PAHs rings. Copyright © 2011 Elsevier Ltd. All rights reserved.

Enhancing Phenolic Contents and Antioxidant Potentials of Antidesma thwaitesianum by Supercritical Carbon Dioxide Extraction

PubMed Central

Poontawee, Warut; Natakankitkul, Surapol; Wongmekiat, Orawan

2015-01-01

Supercritical fluid extraction (SFE) has increasingly gained attention as an alternative technique for extraction of natural products without leaving toxic residues in extracts. Antidesma thwaitesianum Muell. Arg. (Phyllanthaceae), or ma mao, has been reported to exhibit antioxidant health benefits due to its phenolic constituents. To determine whether SFE technique could impact on phenolic contents and associated antioxidant potentials, ripe fruits of Antidesma thwaitesianum (Phyllanthaceae) were extracted using supercritical carbon dioxide (SC-CO2) and conventional solvents (ethanol, water). The results showed that the SC-CO2 extract contained significantly higher yield, total phenolic, flavonoid, and proanthocyanidin contents than those obtained from ethanol and water. It also demonstrated the greatest antioxidant activities as assessed by ABTS radical cation decolorization, DPPH radical scavenging, and ferric reducing antioxidant power (FRAP) assays. Further analysis using high-performance liquid chromatography with diode array and mass spectrometry detectors (HPLC-DAD/MSD) revealed the presence of catechin as a major phenolic compound of Antidesma thwaitesianum (Phyllanthaceae), with the maximum amount detected in the SC-CO2 extract. These data indicate that SFE technology improves both quantity and quality of Antidesma thwaitesianum fruit extract. The findings added more reliability of using this technique to produce high added value products from this medicinal plant. PMID:25977832

Optimization of ultrasonic-assisted extraction of pomegranate (Punica granatum L.) seed oil.

PubMed

Tian, Yuting; Xu, Zhenbo; Zheng, Baodong; Martin Lo, Y

2013-01-01

The effectiveness of ultrasonic-assisted extraction (UAE) of pomegranate seed oil (PSO) was evaluated using a variety of solvents. Petroleum ether was the most effective for oil extraction, followed by n-hexane, ethyl acetate, diethyl ether, acetone, and isopropanol. Several variables, such as ultrasonic power, extraction temperature, extraction time, and the ratio of solvent volume and seed weight (S/S ratio) were studied for optimization using response surface methodology (RSM). The highest oil yield, 25.11% (w/w), was obtained using petroleum ether under optimal conditions for ultrasonic power, extraction temperature, extraction time, and S/S ratio at 140 W, 40 °C, 36 min, and 10 ml/g, respectively. The PSO yield extracted by UAE was significantly higher than by using Soxhlet extraction (SE; 20.50%) and supercriti cal fluid extraction (SFE; 15.72%). The fatty acid compositions were significantly different among the PSO extracted by Soxhlet extraction, SFE, and UAE, with punicic acid (>65%) being the most dominant using UAE. Copyright © 2012 Elsevier B.V. All rights reserved.

Effect of ultrasound on the supercritical CO2 extraction of bioactive compounds from dedo de moça pepper (Capsicum baccatum L. var. pendulum).

PubMed

Dias, Arthur Luiz Baião; Arroio Sergio, Camilla Scarelli; Santos, Philipe; Barbero, Gerardo Fernandéz; Rezende, Camila Alves; Martínez, Julian

2016-07-01

Extracts with bioactive compounds were obtained from the red pepper variety "dedo de moça" (Capsicum baccatum L. var. pendulum) through supercritical fluid extraction with carbon dioxide assisted by ultrasound (SFE-US). The process was tested at pressures of 15, 20 and 25 MPa; temperatures of 40, 50 and 60 °C, and ultrasonic powers of 200, 400 and 600 W applied during 40, 60 and 80 min of extraction. The CO2 mass flow rate was fixed at 1.7569 × 10(-4) kg/s. Global yield, phenolic content, antioxidant capacity and capsaicinoid concentration were evaluated in the extracts. The application of ultrasound raised the global extraction yield of SFE up to 45%. The phenolic content of the extract increased with the application of higher ultrasound power and radiation time. The capsaicinoid yield was also enhanced with ultrasound up to 12%. However, the antioxidant capacity did not increase with the ultrasound application. The BET-based model and the broken and intact cell model fitted well to the kinetic SFE curves. The BET-based model with three adjustable parameters resulted in the best fits to the experimental data. Field emission scanning electron microscopy (FESEM) images showed that SFE disturbed the vegetable matrix, releasing particles from the inner region of the plant cells to their surface. When the ultrasound was applied this effect was more pronounced. On the other hand, cracks, fissures or any sign of rupture were not identified on the sample surface. Copyright © 2016 Elsevier B.V. All rights reserved.

SigmaPlot 2000, Version 6.00, SPSS Inc. Computer Software Test Plan

DOE Office of Scientific and Technical Information (OSTI.GOV)

HURLBUT, S.T.

2000-10-24

SigmaPlot is a vendor software product used in conjunction with the supercritical fluid extraction Fourier transform infrared spectrometer (SFE-FTIR) system. This product converts the raw spectral data to useful area numbers. SigmaPlot will be used in conjunction with procedure ZA-565-301, ''Determination of Moisture by Supercritical Fluid Extraction and Infrared Detection.'' This test plan will be performed in conjunction with or prior to HNF-6936, ''HA-53 Supercritical Fluid Extraction System Acceptance Test Plan'', to perform analyses for water. The test will ensure that the software can be installed properly and will manipulate the analytical data correctly.

A new method based on supercritical fluid extraction for polyacetylenes and polyenes from Echinacea pallida (Nutt.) Nutt. roots.

PubMed

Tacchini, Massimo; Spagnoletti, Antonella; Brighenti, Virginia; Prencipe, Francesco Pio; Benvenuti, Stefania; Sacchetti, Gianni; Pellati, Federica

2017-11-30

The genus Echinacea (Asteraceae) includes species traditionally used in phytotherapy. Among them, Echinacea pallida (Nutt.) Nutt. root extracts are characterized by a representative antiproliferative activity, due to the presence of acetylenic compounds. In this study, supercritical fluid extraction (SFE) was applied and compared with conventional Soxhlet extraction (SE) in order to obtain a bioactive extract highly rich in polyacetylenes and polyenes from E. pallida roots. The composition of the extracts was monitored by means of HPLC-UV/DAD and HPLC-ESI-MS n by using an Ascentis Express C 18 column (150mm×3.0mm I.D., 2.7μm, Supelco, Bellefonte, PA, USA) with a mobile phase composed of (A) water and (B) acetonitrile, under gradient elution. By keeping SFE time at the threshold of 1h (15min static and 45min dynamic for 1 cycle) with the oven temperature set at 40-45°C and 90bar of pressure, an overall extraction yield of 1.18-1.21% (w/w) was obtained, with a high selectivity for not oxidized lipophilic compounds. The biological activity of the extracts was evaluated against human non-small lung A549 and breast carcinoma MCF-7 cancer cell lines. The cytotoxic effect of the SFE extract was more pronounced towards the MCF-7 than the A549 cancer cells, with IC 50 values ranging from 21.01±2.89 to 31.11±2.l4μg/mL; cell viability was affected mainly between 24 and 48h of exposure. The results show the possibility of a new "green" approach to obtain extracts highly rich in genuine polyacetylenes and polyenes from E. pallida roots. The bioactivity evaluation confirmed the cytotoxicity of E. pallida extracts against the considered cancer cell lines, especially against MCF-7 cells, thus suggesting to represent a valuable tool for applicative purposes in cancer prevention. Copyright © 2017 Elsevier B.V. All rights reserved.

Supercritical fluid extraction of 11C-labeled metabolites in tissue using supercritical ammonia.

PubMed

Jacobson, G B; Moulder, R; Lu, L; Bergström, M; Markides, K E; Långström, B

1997-02-01

Supercritical fluid extraction (SFE) of 11C-labeled tracer compounds and their metabolites from biological tissue was performed using supercritical ammonia in an attempt to develop a rapid extraction procedure that allowed subsequent analysis of the labeled metabolites. Metabolites were extracted from kidneys and brain in rats given in vivo injections of the radiotracers O-[2-11C]acetyl-L-carnitine and N-[11C]methylpiperidyl benzilate, respectively. Only a minimal sample pretreatment of the tissue was necessary, i.e., cutting into 10-20 pieces and mixing with the drying agent Hydromatrix, before it was loaded into the extraction vessel. Extraction efficiency was measured for SFE at temperatures over the range of 70-150 degrees C and a pressure of 400 bar. For O-[2-11C]acetyl-L-carnitine, 66% of the radioactivity was trapped in the collected fractions and 12% remained in the extraction vessel. For the more lipophilic N-[11C]methylpiperidyl benzilate, 93% of the activity was collected and less than 1% remained in the extraction vessel. Labeled metabolites were analyzed by LC and also, in the case, of O-[2-11C]acetyl-L-carnitine by LC/MS. The complete extraction procedure, from removal of the biological tissue until an extract was ready for analysis, was 25 min, corresponding to about one half-life of the radionuclide 11C.

Comparison of supercritical fluid extraction and Soxhlet extraction for the determination of PCBs in seaweed samples.

PubMed

Punín Crespo, M O; Lage Yusty, M A

2005-06-01

The efficiency of supercritical fluid extraction for the determination of 12 polychlorinated biphenyls from algae samples is compared to Soxhlet extraction. Analytical detection limits for the individual congeners ranged from 0.62 microgl(-1) to 19 microgl(-1). Recovery was tested for both methods using standard addition procedure. At maximum spike level of concentration, the mean recoveries were not significantly different (P>0.05) of all PCBs studied, with the exception of PCBs 28, 52, 77 and 169. Method precision for Soxhlet extraction (< or =3.9%) was slightly better than for SFE (< or =9.2%). Although both methods yield comparable results, SFE offers the advantage of detecting all PCBs studied at lower concentrations, reducing extraction time, and reducing the amount of solvents needed. The optimized methods were applied to the analysis of three real seaweed samples, except for PCB101 the concentrations of all PCBs were low or below the detection limits. The levels of PCB101 found in sample 1 were 6.6+/-0.54 ng g(-1) d.w., in sample 2 the levels were 8.2+/-0.86 ng g(-1) d.w. and in sample 3 they were 7.7+/-0.08 ng g(-1) d.w.

Optimisation of supercritical carbon dioxide extraction of essential oil of flowers of tea (Camellia sinensis L.) plants and its antioxidative activity.

PubMed

Chen, Zhenchun; Mei, Xin; Jin, Yuxia; Kim, Eun-Hye; Yang, Ziyin; Tu, Youying

2014-01-30

To extract natural volatile compounds from tea (Camellia sinensis) flowers without thermal degradation and residue of organic solvents, supercritical fluid extraction (SFE) using carbon dioxide was employed to prepare essential oil of tea flowers in the present study. Four important parameters--pressure, temperature, static extraction time, and dynamic extraction time--were selected as independent variables in the SFE. The optimum extraction conditions were the pressure of 30 MPa, temperature of 50°C, static time of 10 min, and dynamic time of 90 min. Based on gas chromatography-mass spectrometry analysis, 59 compounds, including alkanes (45.4%), esters (10.5%), ketones (7.1%), aldehydes (3.7%), terpenes (3.7%), acids (2.1%), alcohols (1.6%), ethers (1.3%) and others (10.3%) were identified in the essential oil of tea flowers. Moreover, the essential oil of tea flowers showed relatively stronger DPPH radical scavenging activity than essential oils of geranium and peppermint, although its antioxidative activity was weaker than those of essential oil of clove, ascorbic acid, tert-butylhydroquinone, and butylated hydroxyanisole. Essential oil of tea flowers using SFE contained many types of volatile compounds and showed considerable DPPH scavenging activity. The information will contribute to the future application of tea flowers as raw materials in health-care food and food flavour industries. © 2013 Society of Chemical Industry.

DETERMINATION OF CHLORINATED PHENOLS BY SUPERCRITICAL FLUID EXTRACTION (SFE) -- COUPLED LIQUID CHROMATOGRAPHY (LC) SYSTEM. (R825549C011)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

The stability and degradation kinetics of Sulforaphene in microcapsules based on several biopolymers via spray drying.

PubMed

Tian, Guifang; Li, Yuan; Yuan, Qipeng; Cheng, Li; Kuang, Pengqun; Tang, Pingwah

2015-05-20

Sulforaphene (SFE) was extracted from the radish seeds and the purity of SFE extracted by our laboratory was 95%. It is well known that SFE can prevent cancers. It is also known that SFE is unstable to heat. To overcome the problem, SFE microcapsules using natural biopolymers were prepared by spray drying. The results indicated that SFE microcapsules using hydroxypropyl-β-cyclodextrin (HP-β-CD), maltodextrin (MD) and isolated soybean protein (SPI) as wall materials could effectively improve its stability against heat, especially SFE-loaded HP-β-CD and MD microcapsules. The amount of SFE in the microcapsules was found 20% higher than that of the non-encapsulated SFE under 90 °C in 168 h. Our finding suggested that the rate of degradation of the non-encapsulated and encapsulated SFE with HP-β-CD, MD and SPI followed the first-order kinetics. The speed of the degradation of the encapsulated SFE in biopolymers increased from SFE with HP-β-CD, to SFE with MD, and to SFE-SPI. The non-encapsulated SFE degrades fastest. Copyright © 2015 Elsevier Ltd. All rights reserved.

Differential metabolomic analysis of the potential antiproliferative mechanism of olive leaf extract on the JIMT-1 breast cancer cell line.

PubMed

Barrajón-Catalán, Enrique; Taamalli, Amani; Quirantes-Piné, Rosa; Roldan-Segura, Cristina; Arráez-Román, David; Segura-Carretero, Antonio; Micol, Vicente; Zarrouk, Mokhtar

2015-02-01

A new differential metabolomic approach has been developed to identify the phenolic cellular metabolites derived from breast cancer cells treated with a supercritical fluid extracted (SFE) olive leaf extract. The SFE extract was previously shown to have significant antiproliferative activity relative to several other olive leaf extracts examined in the same model. Upon SFE extract incubation of JIMT-1 human breast cancer cells, major metabolites were identified by using HPLC coupled to electrospray ionization quadrupole-time-of-flight mass spectrometry (ESI-Q-TOF-MS). After treatment, diosmetin was the most abundant intracellular metabolite, and it was accompanied by minor quantities of apigenin and luteolin. To identify the putative antiproliferative mechanism, the major metabolites and the complete extract were assayed for cell cycle, MAPK and PI3K proliferation pathways modulation. Incubation with only luteolin showed a significant effect in cell survival. Luteolin induced apoptosis, whereas the whole olive leaf extract incubation led to a significant cell cycle arrest at the G1 phase. The antiproliferative activity of both pure luteolin and olive leaf extract was mediated by the inactivation of the MAPK-proliferation pathway at the extracellular signal-related kinase (ERK1/2). However, the flavone concentration of the olive leaf extract did not fully explain the strong antiproliferative activity of the extract. Therefore, the effects of other compounds in the extract, probably at the membrane level, must be considered. The potential synergistic effects of the extract also deserve further attention. Our differential metabolomics approach identified the putative intracellular metabolites from a botanical extract that have antiproliferative effects, and this metabolomics approach can be expanded to other herbal extracts or pharmacological complex mixtures. Copyright © 2014 Elsevier B.V. All rights reserved.

Comparison of supercritical fluid extraction and ultrasound-assisted extraction of fatty acids from quince (Cydonia oblonga Miller) seed using response surface methodology and central composite design.

PubMed

Daneshvand, Behnaz; Ara, Katayoun Mahdavi; Raofie, Farhad

2012-08-24

Fatty acids of Cydonia oblonga Miller cultivated in Iran were obtained by supercritical (carbon dioxide) extraction and ultrasound-assisted extraction methods. The oils were analyzed by capillary gas chromatography using mass spectrometric detections. The compounds were identified according to their retention indices and mass spectra (EI, 70eV). The experimental parameters of SFE such as pressure, temperature, modifier volume, static and dynamic extraction time were optimized using a Central Composite Design (CCD) after a 2(5) factorial design. Pressure and dynamic extraction time had significant effect on the extraction yield, while the other factors (temperature, static extraction time and modifier volume) were not identified as significant factors under the selected conditions. The results of chemometrics analysis showed the highest yield for SFE (24.32%), which was obtained at a pressure of 353bar, temperature of 35°C, modifier (methanol) volume of 150μL, and static and dynamic extraction times of 10 and 60min, respectively. Ultrasound-assisted extraction (UAE) of Fatty acids from C. oblonga Miller was optimized, using a rotatable central composite design. The optimum conditions were as follows: solvent (n-hexane) volume, 22mL; extraction time, 30min; and extraction temperature, 55°C. This resulted in a maximum oil recovery of 19.5%. The extracts with higher yield from both methods were subjected to transesterification and GC-MS analysis. The results show that the oil obtained by SFE with the optimal operating conditions allowed a fatty acid composition similar to the oil obtained by UAE in optimum condition and no significant differences were found. The major components of oil extract were Linoleic, Palmitic, Oleic, Stearic and Eicosanoic acids. Copyright © 2012 Elsevier B.V. All rights reserved.

Extraction of three bioactive diterpenoids from Andrographis paniculata: effect of the extraction techniques on extract composition and quantification of three andrographolides using high-performance liquid chromatography.

PubMed

Kumar, Satyanshu; Dhanani, Tushar; Shah, Sonal

2014-10-01

Andrographis paniculata (Burm.f.) wall.ex Nees (Acanthaceae) or Kalmegh is an important medicinal plant finding uses in many Ayurvedic formulations. Diterpenoid compounds andrographolides (APs) are the main bioactive phytochemicals present in leaves and herbage of A. paniculata. The efficiency of supercritical fluid extraction (SFE) using carbon dioxide was compared with the solid-liquid extraction techniques such as solvent extraction, ultrasound-assisted solvent extraction and microwave-assisted solvent extraction with methanol, water and methanol-water as solvents. Also a rapid and validated reverse-phase high-performance liquid chromatography-diode array detection method was developed for the simultaneous determination of the three biologically active compounds, AP, neoandrographolide and andrograpanin, in the extracts of A. paniculata. Under the best SFE conditions tested for diterpenoids, which involved extraction at 60°C and 100 bar, the extractive efficiencies were 132 and 22 µg/g for AP and neoandrographolide, respectively. The modifier percentage significantly affected the extraction efficiency. © The Author [2013]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Isolation of Bioactive Compounds from Sunflower Leaves (Helianthus annuus L.) Extracted with Supercritical Carbon Dioxide.

PubMed

El Marsni, Zouhir; Torres, Ascension; Varela, Rosa M; Molinillo, José M G; Casas, Lourdes; Mantell, Casimiro; Martinez de la Ossa, Enrique J; Macias, Francisco A

2015-07-22

The work described herein is a continuation of our initial studies on the supercritical fluid extraction (SFE) with CO2 of bioactive substances from Helianthus annuus L. var. Arianna. The selected SFE extract showed high activity in the wheat coleoptile bioassay, in Petri dish phytotoxicity bioassays, and in the hydroponic culture of tomato seeds. Chromatographic fractionations of the extracts and a spectroscopic analysis of the isolated compounds showed 52 substances belonging to 10 different chemical classes, which were mainly sesquiterpene lactones, diterpenes, and flavonoids. Heliannuol M (31), helivypolides K and L (36, 37), and helieudesmanolide B (38) are described for the first time in the literature. Metabolites have been tested in the etiolated wheat coleoptile bioassay with good results in a noteworthy effect on germination. The most active compounds were also tested on tomato seeds, heliannuol A (30) and leptocarpin (45) being the most active, with values similar to those of the commercial herbicide.

Qualitative comparison of active compounds between red and green Mariposa Christia Vespertillonis leaves extracts

NASA Astrophysics Data System (ADS)

Osman, M. S.; Ghani, Z. A.; Ismail, N. F.; Razak, N. A. A.; Jaapar, J.; Ariff, M. A. M.

2017-09-01

At present time, Mariposa Christia Vespertillonis (MCV) leave has become popular for its anti-cancer and thus is used widely among the traditional medicine in Malaysia. There are several types of MCV plants and the one that is currently well-known for traditional medicine in Malaysia is the green MCV (GMCV). Red MCV (RMCV) is another type of MCV plant which can also be found easily in Malaysia. In this study, the active compounds for GMCV and RMCV will be compared and analyzed by using Liquid Chromatography - Mass Spectrometry (LC-MS). The active compounds will be extracted from the MCV leaves by using Supercritical Fluid Extraction (SFE). The findings of this study indicates the global yield of the MCV oils is 31 mg/g while the compound identification indicates the presence of anti-cancer, anti-inflammatory and beneficial phytochemicals. This work is an explorative study to reveal the potential of MCV to be extracted using SFE method as potential therapeutic plants for the traditional medicine in Malaysia.

Use of on-line supercritical fluid extraction-supercritical fluid chromatography/tandem mass spectrometry to analyze disease biomarkers in dried serum spots compared with serum analysis using liquid chromatography/tandem mass spectrometry.

PubMed

Suzuki, Makoto; Nishiumi, Shin; Kobayashi, Takashi; Sakai, Arata; Iwata, Yosuke; Uchikata, Takato; Izumi, Yoshihiro; Azuma, Takeshi; Bamba, Takeshi; Yoshida, Masaru

2017-05-30

The analytical stability and throughput of biomarker assays based on dried serum spots (DSS) are strongly dependent on the extraction process and determination method. In the present study, an on-line system based on supercritical fluid extraction-supercritical fluid chromatography coupled with tandem mass spectrometry (SFE-SFC/MS/MS) was established for analyzing the levels of disease biomarkers in DSS. The chromatographic conditions were investigated using the ODS-EP, diol, and SIL-100A columns. Then, we optimized the SFE-SFC/MS/MS method using the diol column, focusing on candidate biomarkers of oral, colorectal, and pancreatic cancer that were identified using liquid chromatography (LC)/MS/MS. By using this system, four hydrophilic metabolites and 17 hydrophobic metabolites were simultaneously detected within 15 min. In an experiment involving clinical samples, PC 16:0-18:2/16:1-18:1 exhibited 93.8% sensitivity and 64.3% specificity, whereas PC 17:1-18:1/17:0-18:2 showed 81.3% sensitivity and 92.9% specificity for detecting oral cancer. In addition, assessments of the creatine levels demonstrated 92.3% sensitivity and 78.6% specificity for detecting colorectal cancer. The results of this study indicate that our method has great potential for clinical diagnosis and would be suitable for large-scale screening. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Effect of cosmetic matrices on the release and odour profiles of the supercritical CO2 extract of Origanum majorana L.

PubMed

Costa, P; Velasco, C V; Loureiro, J M; Rodrigues, A E

2016-08-01

In this study, the effect of different cosmetic matrices on the release profile and odour intensity of the fragrance O. majorana was investigated for the first time. The fragrance compounds of O. majorana were extracted by supercritical fluid extraction using carbon dioxide (SFE-CO2 ) at 40°C and two operating pressures (8.5 and 10 MPa), and their chemical profiles were assessed by gas chromatography with flame ionization detector coupled with mass spectrometry (GC-FID/MS). Lastly, the fragrance compounds were incorporated into three cosmetic matrices (glycerine, dipropylene glycol and skin lotion) to assess their release and odour profiles over time using dynamic headspace (DHS)/GC-FID/MS and Odour Value concept, respectively. The SFE-CO2 enabled recovering extracts with the pleasant scent of the living plant, and the increment of pressure induced an increase on the extraction yield. GC-FID/MS analyses revealed that oxygen-containing monoterpenes was the principal group of components identified in both SFE-CO2 extracts. The fragrance compounds were more retained in dipropylene glycol, and the major deviations from the original odour intensity (control) were observed in the presence of dipropylene glycol and skin lotion. The hydrophilic character of the cosmetic matrices strongly influenced the release of the fragrance compounds, thus affecting the odour profile of the studied mixtures. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

A TANDEM SUPERCRITICAL FLUID EXTRACTION (SFE) AND LIQUID CHROMATOGRAPHY (LC) SYSTEM FOR DETERMINATION OF CHLORINATED PHENOLS IN SOLID MATRIEES. (R825549C049)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

A TANDEM SUPERCRITICAL FLUID EXTRACTION (SFE) AND LIQUID CHROMATOGRAPHY (LC) SYSTEM FOR DETERMINATION OF CHLORINATED PHENOLS IN SOLID MATRICES. (R825549C011)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

Removal of common organic solvents from aqueous waste streams via supercritical C02 extraction: a potential green approach to sustainable waste management in the pharmaceutical industry.

PubMed

Leazer, Johnnie L; Gant, Sean; Houck, Anthony; Leonard, William; Welch, Christopher J

2009-03-15

Supercritical CO2 extraction of aqueous streams is a convenient and effective method to remove commonly used solvents of varying polarities from aqueous waste streams. The resulting aqueous layers can potentially be sewered; whereas the organic layer can be recovered for potential reuse. Supercritical fluid extraction (SFE) is a technology that is increasingly being used in commercial processes (1). Supercritical fluids are well suited for extraction of a variety of media, including solids, natural products, and liquid products. Many supercritical fluids have low critical temperatures, allowing for extractions to be done at modestly low temperatures, thus avoiding any potential thermal decomposition of the solutes under study (2). Furthermore, the CO2 solvent strength is easily tuned by adjusting the density of the supercritical fluid (The density is proportional to the pressure of the extraction process). Since many supercritical fluids are gases at ambient temperature, the extract can be concentrated by simply venting the reaction mixture to a cyclone collection vessel, using appropriate safety protocols.

Influence of extraction technique on the anti-oxidative potential of hawthorn (Crataegus monogyna) extracts in bovine muscle homogenates.

PubMed

Shortle, E; O'Grady, M N; Gilroy, D; Furey, A; Quinn, N; Kerry, J P

2014-12-01

Six extracts were prepared from hawthorn (Crataegus monogyna) leaves and flowers (HLF) and berries (HB) using solid-liquid [traditional (T) (HLFT, HBT), sonicated (S) (HLFS, HBS)] and supercritical fluid (C) extraction (HLFC, HBC) techniques. The antioxidant activities of HLF and HB extracts were characterised using in vitro antioxidant assays (TPC, DPPH, FRAP) and in 25% bovine muscle (longissimus lumborum) homogenates (lipid oxidation (TBARS), oxymyoglobin (% of total myoglobin)) after 24h storage at 4°C. Hawthorn extracts exhibited varying degrees of antioxidant potency. In vitro and muscle homogenate (TBARS) antioxidant activity followed the order: HLFS>HLFT and HBT>HBS. In supercritical fluid extracts, HLFC>HBC (in vitro antioxidant activity) and HLFC≈HBC (TBARS). All extracts (except HBS) reduced oxymyoglobin oxidation. The HLFS extract had the highest antioxidant activity in all test systems. Supercritical fluid extraction (SFE) exhibited potential as a technique for the manufacture of functional ingredients (antioxidants) from hawthorn for use in muscle foods. Copyright © 2014 Elsevier Ltd. All rights reserved.

Characterization of medium-chain triacylglycerol (MCT)-enriched seed oil from Cinnamomum camphora (Lauraceae) and its oxidative stability.

PubMed

Hu, Jiang-Ning; Zhang, Bing; Zhu, Xue-Mei; Li, Jing; Fan, Ya-Wei; Liu, Rong; Tang, Liang; Lee, Ki-Teak; Deng, Ze-Yuan

2011-05-11

Medium-chain triacylglycerol (MCT)-enriched oil was extracted by supercritical fluid extraction of carbon dioxide (SFE-CO(2)) from Cinnamomum camphora seeds. The SFE-CO(2) process was optimized using the Box-Behnken design (BBD). The maximum oil yield (42.82%) was obtained under the optimal SFE-CO(2) conditions: extraction pressure, 21.16 MPa; extraction temperature, 45.67 °C; and extraction time, 2.38 h. Subsequently, the physicochemical characteristics, fatty acid composition, triacylglycerol (TAG) composition, tocopherol content, and DSC profile as well as oxidative stabilities of C. camphora seed oil (CCSO) were studied. Results showed that CCSO contained two major medium-chain fatty acids, capric acid (53.27%) and lauric acid (39.93%). The predominant TAG species in CCSO was LaCC/CLaC (ECN 32, 79.29%). Meanwhile, it can be found that CCSO had much higher oxidative stabilities than coconut oil due to the higher content of tocopherols in CCSO (α-tocopherol, 8.67 ± 0.51 mg/100 g; γ-tocopherol, 22.6 ± 1.02 mg/100 g; δ-tocopherol, 8.38 ± 0.47 mg/100 g). Conclusively, CCSO with such a high level of MCTs and high oxidative stabilities could be potentially applied in special food for specific persons such as weak patients and overweight persons because oils enriched in MCTs can be rapidly absorbed into body to provide energy without fat accumulation.

Supercritical Fluid Extraction and Analysis of Tropospheric Aerosol Particles

NASA Astrophysics Data System (ADS)

Hansen, Kristen J.

An integrated sampling and supercritical fluid extraction (SFE) cell has been designed for whole-sample analysis of organic compounds on tropospheric aerosol particles. The low-volume extraction cell has been interfaced with a sampling manifold for aerosol particle collection in the field. After sample collection, the entire SFE cell was coupled to a gas chromatograph; after on-line extraction, the cryogenically -focused sample was separated and the volatile compounds detected with either a mass spectrometer or a flame ionization detector. A 20-minute extraction at 450 atm and 90 ^circC with pure supercritical CO _2 is sufficient for quantitative extraction of most volatile compounds in aerosol particle samples. A comparison between SFE and thermal desorption, the traditional whole-sample technique for analyses of this type, was performed using ambient aerosol particle samples, as well as samples containing known amounts of standard analytes. The results of these studies indicate that SFE of atmospheric aerosol particles provides quantitative measurement of several classes of organic compounds. SFE provides information that is complementary to that gained by the thermal desorption analysis. The results also indicate that SFE with CO _2 can be validated as an alternative to thermal desorption for quantitative recovery of several organic compounds. In 1989, the organic constituents of atmospheric aerosol particles collected at Niwot Ridge, Colorado, along with various physical and meteorological data, were measured during a collaborative field study. Temporal changes in the composition of samples collected during summertime at the rural site were studied. Thermal desorption-GC/FID was used to quantify selected compounds in samples collected during the field study. The statistical analysis of the 1989 Niwot Ridge data set is presented in this work. Principal component analysis was performed on thirty-one variables selected from the data set in order to ascertain different source and process components, and to examine concentration changes in groups of variables with respect to time of day and meteorological conditions. Seven orthogonal groups of variables resulted from the statistical analysis; the groups serve as molecular markers for different biologic and anthropogenic emission sources. In addition, the results of the statistical analysis were used to investigate how several emission source contributions vary with respect to local atmospheric dynamics. Field studies were conducted in the urban environment in and around Boulder, CO. to characterize the dynamics, chemistry, and emission sources which affect the composition and concentration of different size-fractions of aerosol particles in the Boulder air mass. Relationships between different size fractions of particles and some gas-phase pollutants were elucidated. These field studies included an investigation of seasonal variations in the organic content and concentration of aerosol particles, and how these characteristics are related to local meteorology and to the concentration of some gas-phase pollutants. The elemental and organic composition of aerosol particles was investigated according to particle size in preliminary studies of size-differentiated samples of aerosol particles. In order to aid in future studies of urban aerosol particles, samples were collected at a forest fire near Boulder. Molecular markers specific to wood burning processes will be useful indicators of residential wood burning activities in future field studies.

Development of new critical fluid-based processing methods for nutraceuticals and natural products

DOE Office of Scientific and Technical Information (OSTI.GOV)

King, J. W.

2004-01-01

The development of new supercritical fluid processing technology as applied to nutraceuticals and natural products is no longer confined to using just supercritical fluid extraction (SFE) and supercritical carbon dioxide (SC-CO{sub 2}). Recently reported advances have been focused on modifying natural products and improving functionality of an end product using newer experimental techniques and fluid phases. In this presentation four focus areas will be emphasized: (1) control of particle size/morphology and encapsulation of the nutraceutical ingredients, (2) the use of combinatorial methodology to optimize critical fluid processing, (3) application of sub-critical water as a complementary medium for processing natural products,more » and (4) an assessment of the current state of products and processing which use critical fluid to produce nutraceutical and natural products for the food and cosmetic marketplace. Application of the various particle fomiation processes conducted in the presence of critical fluid media, such as: CPF, SAS, DELOS, RESS, PGSS, and GAS, can be used to produce particles of small and uniform distribution, having unique morphologies, that facilitate rapid dissolution or sustained release of many nutraceutical ingredients. These substances have included: therapeutic spices, phystosterols, vitamins, phospholpids, and carotenoids. Accelerating the development of critical fluid processing has been the application of combinatorial methodology to optimize extraction, fractionation, and/or reactions in near-, SC-, or subcritical fluid media. This is frequently accomplished by using sequential or multichannel automated instrumentation that was originally designed for analytical purposes. Several examples will be provided of rapidly assessing the extraction of anthocyanins with sub-critical water and the SFE of natural products. However, differences do exist in conducting experiments on the above instrumentation vs. scaled-up continuous processes, which will be noted. Sub-critical water is finding increase use as an extraction/fractionation or reaction medium. The literature reports applications for the extraction spices, natural antioxidants (rosemary, anthocyanins, etc.), and herbal components (tea and coffee ingredients), Our studies and the literature provide adequate correlations of solute solubility in sub-critical water as well as models for the kinetics of extraction in this medium. Finally, the current state of critical fluid technology as applied to natural products and nutraceuticals will be assessed; noting specific processes, organizations, and products that exist.« less

Bioassay-guided supercritical fluid extraction of cyclooxygenase-2 inhibiting substances in Plantago major L.

PubMed

Stenholm, A; Göransson, U; Bohlin, L

2013-02-01

Selective extraction of plant materials is advantageous for obtaining extracts enriched with desired constituents, thereby reducing the need for subsequent chromatography purification. Such compounds include three cyclooxygenase-2 (COX-2) inhibitory substances in Plantago major L. targeted in this investigation: α-linolenic acid (α-LNA) (18:3 ω-3) and the triterpenic acids ursolic acid and oleanolic acid. To investigate the scope for tuning the selectivity of supercritical fluid extraction (SFE) using bioassay guidance, and Soxhlet extraction with dichloromethane as solvent as a reference technique, to optimise yields of these substances. Extraction parameters were varied to optimise extracts' COX-2/COX-1 inhibitory effect ratios. The crude extracts were purified initially using a solid phase extraction (SPE) clean-up procedure and the target compounds were identified with GC-MS, LC-ESI-MS and LC-ESI-MS² using GC-FID for quantification. α-LNA was preferentially extracted in dynamic mode using unmodified carbon dioxide at 40°C and 172 bar, at a 0.04% (w/w) yield with a COX-2/COX-1 inhibitory effect ratio of 1.5. Ursolic and oleanolic acids were dynamically extracted at 0.25% and 0.06% yields, respectively, with no traces of (α-LNA) and a COX-2/COX-1-inhibitory effect ratio of 1.1 using 10% (v/v) ethanol as polar modifier at 75°C and 483 bar. The Soxhlet extracts had ursolic acid, oleanolic acid and αLNA yields up to 1.36%, 0.34% and 0.15%, respectively, with a COX-2/COX-1 inhibitory effect ratio of 1.2. The target substances can be extracted selectively by bioassay guided optimisation of SFE conditions. Copyright © 2012 John Wiley & Sons, Ltd.

Analysis of carbendazim, benomyl, thiophanate methyl and 2,4-dichlorophenoxyacetic acid in fruits and vegetables after supercritical fluid extraction.

PubMed

Anastassiades, M; Schwack, W

1998-10-30

Simple methods for the analysis of carbendazim, benomyl and thiophanate methyl in fruits and vegetables and of 2,4-D in citrus fruits are presented. Sample preparation involves supercritical fluid extraction with carbon dioxide and further analysis is performed without any additional clean-up by GC-MS after derivatisation or directly by HPLC-diode array detection. The SFE methods presented are clearly faster and more cost effective than traditional solvent based approaches. The recoveries, detection limits and repeatabilities achieved, meet the needs of tolerance level monitoring of these compounds in fruits and vegetables.

Vaccinium meridionale Swartz Supercritical CO₂ Extraction: Effect of Process Conditions and Scaling Up.

PubMed

López-Padilla, Alexis; Ruiz-Rodriguez, Alejandro; Restrepo Flórez, Claudia Estela; Rivero Barrios, Diana Marsela; Reglero, Guillermo; Fornari, Tiziana

2016-06-25

Vaccinium meridionale Swartz (Mortiño or Colombian blueberry) is one of the Vaccinium species abundantly found across the Colombian mountains, which are characterized by high contents of polyphenolic compounds (anthocyanins and flavonoids). The supercritical fluid extraction (SFE) of Vaccinium species has mainly focused on the study of V. myrtillus L. (blueberry). In this work, the SFE of Mortiño fruit from Colombia was studied in a small-scale extraction cell (273 cm³) and different extraction pressures (20 and 30 MPa) and temperatures (313 and 343 K) were investigated. Then, process scaling-up to a larger extraction cell (1350 cm³) was analyzed using well-known semi-empirical engineering approaches. The Broken and Intact Cell (BIC) model was adjusted to represent the kinetic behavior of the low-scale extraction and to simulate the large-scale conditions. Extraction yields obtained were in the range 0.1%-3.2%. Most of the Mortiño solutes are readily accessible and, thus, 92% of the extractable material was recovered in around 30 min. The constant CO₂ residence time criterion produced excellent results regarding the small-scale kinetic curve according to the BIC model, and this conclusion was experimentally validated in large-scale kinetic experiments.

Vaccinium meridionale Swartz Supercritical CO2 Extraction: Effect of Process Conditions and Scaling Up

PubMed Central

López-Padilla, Alexis; Ruiz-Rodriguez, Alejandro; Restrepo Flórez, Claudia Estela; Rivero Barrios, Diana Marsela; Reglero, Guillermo; Fornari, Tiziana

2016-01-01

Vaccinium meridionale Swartz (Mortiño or Colombian blueberry) is one of the Vaccinium species abundantly found across the Colombian mountains, which are characterized by high contents of polyphenolic compounds (anthocyanins and flavonoids). The supercritical fluid extraction (SFE) of Vaccinium species has mainly focused on the study of V. myrtillus L. (blueberry). In this work, the SFE of Mortiño fruit from Colombia was studied in a small-scale extraction cell (273 cm3) and different extraction pressures (20 and 30 MPa) and temperatures (313 and 343 K) were investigated. Then, process scaling-up to a larger extraction cell (1350 cm3) was analyzed using well-known semi-empirical engineering approaches. The Broken and Intact Cell (BIC) model was adjusted to represent the kinetic behavior of the low-scale extraction and to simulate the large-scale conditions. Extraction yields obtained were in the range 0.1%–3.2%. Most of the Mortiño solutes are readily accessible and, thus, 92% of the extractable material was recovered in around 30 min. The constant CO2 residence time criterion produced excellent results regarding the small-scale kinetic curve according to the BIC model, and this conclusion was experimentally validated in large-scale kinetic experiments. PMID:28773640

Metal speciation of environmental samples using SPE and SFC-AED analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mitchell, S.C.; Burford, M.D.; Robson, M.

1995-12-31

Due to growing public concern over heavy metals in the environment, soil, water and air particulate samples azre now routinely screened for their metal content. Conventional metal analysis typically involves acid digestion extraction and results in the generation of large aqueous and organic solvent waste. This harsh extraction process is usually used to obtain the total metal content of the sample, the extract being analysed by atomic emission or absorption spectroscoply techniques. A more selective method of metal extraction has been investigated which uses a supercritical fluid modified with a complexing agent. The relatively mild extraction method enables both organometallicmore » and inorganic metal species to be recovered intact. The various components from the supercritical fluid extract can be chromatographically separated using supercritical fluid chromatography (SFC) and positive identification of the metals achieved using atomic emission detection (AED). The aim of the study is to develop an analytical extraction procedure which enables a rapid, sensitive and quantitative analysis of metals in environmental samples, using just one extraction (eg SFE) and one analysis (eg SFC-AED) procedure.« less

Auraptene, a Major Compound of Supercritical Fluid Extract of Phalsak (Citrus Hassaku Hort ex Tanaka), Induces Apoptosis through the Suppression of mTOR Pathways in Human Gastric Cancer SNU-1 Cells

PubMed Central

Moon, Jeong Yong; Kim, Hyeonji; Cho, Somi Kim

2015-01-01

The supercritical extraction method is a widely used process to obtain volatile and nonvolatile compounds by avoiding thermal degradation and solvent residue in the extracts. In search of phytochemicals with potential therapeutic application in gastric cancer, the supercritical fluid extract (SFE) of phalsak (Citrus hassaku Hort ex Tanaka) fruits was analyzed by gas chromatography-mass spectrometry (GC-MS). Compositional analysis in comparison with the antiproliferative activities of peel and flesh suggested auraptene as the most prominent anticancer compound against gastric cancer cells. SNU-1 cells were the most susceptible to auraptene-induced toxicity among the tested gastric cancer cell lines. Auraptene induced the death of SNU-1 cells through apoptosis, as evidenced by the increased cell population in the sub-G1 phase, the appearance of fragmented nuclei, the proteolytic cleavage of caspase-3 and poly(ADP-ribose) polymerase (PARP) protein, and depolarization of the mitochondrial membrane. Interestingly, auraptene induces an increase in the phosphorylation of Akt, which is reminiscent of the effect of rapamycin, the mTOR inhibitor that triggers a negative feedback loop on Akt/mTOR pathway. Taken together, these findings provide valuable insights into the anticancer effects of the SFE of the phalsak peel by revealing that auraptene, the major compound of it, induced apoptosis in accompanied with the inhibition of mTOR in SNU-1 cells. PMID:26351512

Chemical composition and antioxidant/antimicrobial activities in supercritical carbon dioxide fluid extract of Gloiopeltis tenax.

PubMed

Zheng, Jiaojiao; Chen, Yicun; Yao, Fen; Chen, Weizhou; Shi, Ganggang

2012-12-01

Gloiopeltis tenax (G. tenax) is widely distributed along the Chinese coastal areas and is commonly used in the treatment of diarrhea and colitis. This study aimed at investigating the bioactivities of the volatile constituents in G. tenax. We extracted the essential constituents of G. tenax by supercritical carbon dioxide extraction (CO₂-SFE), then identified and analyzed the constituents by gas chromatography-mass spectrometry (GC-MS). In total, 30 components were identified in the G. tenax extract. The components showed remarkable antioxidant activity (radical scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH)), lipid peroxidation inhibition capacity (in a β-carotene/linoleic acid-coupled oxidation reaction), and hydroxyl radical-scavenging activity (by deoxyribose degradation by iron-dependent hydroxyl radical), compared to butylated hydroxytoluene. In microdilution assays, G. tenax extracts showed a moderate inhibitory effects on Staphyloccocus aureus (minimum inhibitory concentration (MIC) = 3.9 mg/mL), Enterococcus faecalis (7.8 mg/mL), Pseudomonas aeruginosa (15.6 mg/mL), and Escherichia coli (3.9 mg/mL). Antioxidant and antimicrobial activities of G. tenax were related to the active chemical composition. These results suggest that the CO₂-SFE extract from G. tenax has potential to be used as a natural antioxidant and antimicrobial agent in food processing.

Identification and isolation of the cyclooxygenase-2 inhibitory principle in Isatis tinctoria.

PubMed

Danz, H; Stoyanova, S; Wippich, P; Brattström, A; Hamburger, M

2001-07-01

Various extracts prepared from the traditional dye and medicinal plant Isatis tinctoria L. were submitted to a broad in vitro screening against 16 anti-inflammatory targets. Dichloromethane (DCM) extracts from dried leaves showed a marked cyclooxygenase (COX) inhibitory activity with a preferential effect on COX-2 catalysed prostaglandin synthesis. A supercritical fluid extraction (SFE) procedure employing CO2-modifier mixtures was developed by which the bioactivity profile and chromatographic fingerprint of the DCM extract could be reproduced. High-resolution activity directed on-line identification of the COX-2 inhibitory principle, using a combination of LC-DAD-MS with a microtitre-based bioassay, led to the identification of tryptanthrin (1) as the constituent responsible for essentially all COX-2 inhibitory activity in the crude extract. Following on-line identification, 1 was isolated at preparative scale and its structure confirmed by comparison with synthetic tryptanthrin. In an assay with lipopolysaccharide stimulated Mono Mac 6 cells, tryptanthrin (1) was of comparable potency (IC50 = 64 nM) than the preferential COX-2 inhibitors nimesulide (IC50 = 39 nM) and NS 398 (IC50 = 2 nM). The SFE extract and 1 showed no cytotoxicity in Mono Mac 6 and RAW 264.7 cells when tested at 100 microg/ml and 10 microM, respectively.

Chemical Composition and Antioxidant/Antimicrobial Activities in Supercritical Carbon Dioxide Fluid Extract of Gloiopeltis tenax

PubMed Central

Zheng, Jiaojiao; Chen, Yicun; Yao, Fen; Chen, Weizhou; Shi, Ganggang

2012-01-01

Gloiopeltis tenax (G. tenax) is widely distributed along the Chinese coastal areas and is commonly used in the treatment of diarrhea and colitis. This study aimed at investigating the bioactivities of the volatile constituents in G. tenax. We extracted the essential constituents of G. tenax by supercritical carbon dioxide extraction (CO2-SFE), then identified and analyzed the constituents by gas chromatography-mass spectrometry (GC-MS). In total, 30 components were identified in the G. tenax extract. The components showed remarkable antioxidant activity (radical scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH)), lipid peroxidation inhibition capacity (in a β-carotene/linoleic acid-coupled oxidation reaction), and hydroxyl radical-scavenging activity (by deoxyribose degradation by iron-dependent hydroxyl radical), compared to butylated hydroxytoluene. In microdilution assays, G. tenax extracts showed a moderate inhibitory effects on Staphyloccocus aureus (minimum inhibitory concentration (MIC) = 3.9 mg/mL), Enterococcus faecalis (7.8 mg/mL), Pseudomonas aeruginosa (15.6 mg/mL), and Escherichia coli (3.9 mg/mL). Antioxidant and antimicrobial activities of G. tenax were related to the active chemical composition. These results suggest that the CO2-SFE extract from G. tenax has potential to be used as a natural antioxidant and antimicrobial agent in food processing. PMID:23342386

Development of supercritical carbon dioxide extraction with a solid phase trap for dioxins in soils and sediments.

PubMed

Miyawaki, Takashi; Kawashima, Ayato; Honda, Katsuhisa

2008-01-01

A method involving supercritical fluid extraction (SFE) with a solid phase trap containing activated alumina was investigated for the rapid analysis of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin like polychlorinated biphenyls (DL-PCBs) in soils and sediments. The samples were extracted by using supercritical carbon dioxide with water (2% versus CO(2) flow velocity) being used as an entrainer at a pressure of 30 MPa and a temperature of 130 degrees C for 50 min. The extracts were adsorbed on an activated alumina trap that was maintained at a temperature of 150 degrees C, and then, PCDD/DFs and DL-PCBs were eluted with 20 ml of hexane at 60 degrees C. After concentration, they were measured with a high-resolution gas chromatograph interfaced to a high-resolution mass spectrometric detector. The average concentrations of PCDD/DFs and DL-PCBs corresponded to the results obtained by the conventional method, and the reproducibility of this SFE method was below 21% of the relative standard deviations for all samples. The total time required for the analysis of the pretreatment of this method was only 2 h.

Comparison of chemical composition and antibacterial activity of Nigella sativa seed essential oils obtained by different extraction methods.

PubMed

Kokoska, L; Havlik, J; Valterova, I; Sovova, H; Sajfrtova, M; Jankovska, I

2008-12-01

Nigella sativa L. seed essential oils obtained by hydrodistillation (HD), dry steam distillation (SD), steam distillation of crude oils obtained by solvent extraction (SE-SD), and supercritical fluid extraction (SFE-SD) were tested for their antibacterial activities, using the broth microdilution method and subsequently analyzed by gas chromatography and gas chromatography-mass spectrometry. The results showed that the essential oils tested differed markedly in their chemical compositions and antimicrobial activities. The oils obtained by HD and SD were dominated by p-cymene, whereas the major constituent identified in both volatile fractions obtained by SD of extracted oils was thymoquinone (ranging between 0.36 and 0.38 g/ml, whereas in oils obtained by HD and SD, it constituted only 0.03 and 0.05 g/ml, respectively). Both oils distilled directly from seeds showed lower antimicrobial activity (MICs > or = 256 and 32 microg/ml for HD and SD, respectively) than those obtained by SE-SD and SFE-SD (MICs > or = 4 microg/ml). All oil samples were significantly more active against gram-positive than against gram-negative bacteria. Thymoquinone exhibited potent growth-inhibiting activity against gram-positive bacteria, with MICs ranging from 8 to 64 microg/ml.

Quantification of active principles and pigments in leaf extracts of Isatis tinctoria by HPLC/UV/MS.

PubMed

Mohn, Tobias; Potterat, Olivier; Hamburger, Matthias

2007-02-01

An HPLC method has been developed and validated for the quantification of the pharmacologically active principles tryptanthrin (1), 1,3-dihydro-3-[(4-hydroxy-3,5-dimethoxyphenyl)methylene]-2 H-indol-2-one (indolinone) (3), indirubin (4), alpha-linolenic acid (2), and indigo (5), an isomer of indirubin, in extracts from the traditional anti-inflammatory plant Isatis tinctoria (woad). The chromatographic separation was performed on a C-18 column with a linear gradient of acetonitrile in water containing 0.1% formic acid. The method combines UV and electrospray MS detection in the positive ion mode for the detection of the alkaloids, with a switch to the negative mode for the analysis of alpha-linolenic acid. The method was applied to the analysis of woad extracts obtained by supercritical fluid (SFE) CO2 extraction, and by pressurized liquid extraction (PLE) with dichloromethane and methanol, respectively. While the highest concentration of alpha-linolenic acid was found in the SFE extract (7.43%), the concentrations of tryptanthrin , indolinone, indirubin and indigo were the highest in the dichloromethane extract (0.30, 0.035, 2.48 and 0.84%, respectively). Compound 3 was not detected in the methanolic extract and only traces of compounds 1, 4 and 5 and low amount of alpha-linolenic acid (0.39%) were present in this extract.

Extraction fatty acid as a source to produce biofuel in microalgae Chlorella sp. and Spirulina sp. using supercritical carbon dioxide

NASA Astrophysics Data System (ADS)

Tai, Do Chiem; Hai, Dam Thi Thanh; Vinh, Nguyen Hanh; Phung, Le Thi Kim

2016-06-01

In this research, the fatty acids of isolated microalgae were extracted by some technologies such as maceration, Soxhlet, ultrasonic-assisted extraction and supercritical fluid extraction; and analyzed for biodiesel production using GC-MS. This work deals with the extraction of microalgae oil from dry biomass by using supercritical fluid extraction method. A complete study at laboratory of the influence of some parameters on the extraction kinetics and yields and on the composition of the oil in terms of lipid classes and profiles is proposed. Two types of microalgae were studied: Chlorella sp. and Spirulina sp. For the extraction of oil from microalgae, supercritical CO2 (SC-CO2) is regarded with interest, being safer than n-hexane and offering a negligible environmental impact, a short extraction time and a high-quality final product. Whilst some experimental papers are available on the supercritical fluid extraction (SFE) of oil from microalgae, only limited information exists on the kinetics of the process. These results demonstrate that supercritical CO2 extraction is an efficient method for the complete recovery of the neutral lipid phase.

Free radical scavenging of grape pomace extracts from Cabernet sauvingnon (Vitis vinifera).

PubMed

de Campos, Luanda M A S; Leimann, Fernanda V; Pedrosa, Rozangela Curi; Ferreira, Sandra R S

2008-11-01

Pressed grape pomace obtained from the wine production of Cabernet sauvignon (Vitis vinifera) vintage was dried until 9.8% moisture content, ground and submitted to extraction of soluble components from different extraction techniques. Low pressure extractions were performed with ethanol maceration followed by fractionation with n-hexane, dichloromethane, butanol and ethyl acetate. These solvents were furthermore applied for soxhlet extraction. Supercritical fluid extraction (SFE) was also performed to obtain grape pomace extracts by using pure CO2 and CO2 with ethanol as co-solvent in concentrations of 10, 15 and 20%w/w. The operating condition used in high pressure extractions was 150bar and 40 degrees C. The antioxidant activity of the grape pomace extracts was determined considering the free radical scavenging assay using 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and was correlated with the total phenol content determined according to the Folin-Ciocalteu method. The results obtained in DPPH tests indicate the highest antioxidant activity of 96.6+/-0.3%AA, with an IC50 value of 13+/-1, for the extracts obtained with ethyl acetate in solid-liquid extraction. The highest yield values were achieved in soxhlet extraction with ethanol (13.2%w/w) and with butanol (12.2%w/w), and also by SFE with 15% ethanol (9.2%w/w). The lipophilic composition of grape pomace extracts was evaluated by gas chromatography-mass spectrometry with the identification of components like linoleic acid and ethyl linoleate, with important therapeutic activities.

Clinical Outcome And Arginine Serum of Acute Ischemic Stroke Patients Supplemented by Snakehead Fish Extract

NASA Astrophysics Data System (ADS)

Pudjonarko, Dwi; Retnaningsih; Abidin, Zainal

2018-02-01

Background: Levels of arginine associated with clinical outcome in acute ischemic stroke (AIS). Arginine is a protein needed to synthesis nitric oxide (NO), a potential vasodilator and antioxidant. Snakehead fish is a source of protein which has antioxidant activity. Snakehead fish contains mineral, vitamin, and amino acids. One of the amino acids that were found quite high in snakehead fish extract is arginine. The aim of this study was done to determine the effect of snakehead fish extracts (SFE) on serum arginin levels and clinical outcome of AIS patients. Methods: It was double-blind randomized pretest-posttest control group design, with. AIS patients were divided into two groups i.e. snakehead fish extracts (SFE) and control. SFE group were administered 15 grams SFE for 7 days . Arginine serum levels and clinical outcome (measured by National Institute of Health Stroke Scale = NIHSS) were measured before and after treatment, other related factors were also analyzed in Logistic regression. Results: A total of 42 subjects who were performed random allocation as SFE or control group. There was no differences in subject characteristics between the two groups. There was a differences Δ arginine serum levels between SFE and control (33.6±19.95 μmol/L 0.3±2.51 μmol/L p<0.001). Change in NIHSS score in SFE improved significantly compared to the control group (4.14 ± 2.03; 2.52 ± 1.81;p=0.009 ). Logistic regression analysis showed only female gender factor that affected on improvement of NIHSS (OR=7; p=0,01). Conclusion: There is Clinical outcome improvement and enhancement of arginine serum levels in AIS patient with snakehead fish extract supplementation.

Comparative Study of Green Sub- and Supercritical Processes to Obtain Carnosic Acid and Carnosol-Enriched Rosemary Extracts with in Vitro Anti-Proliferative Activity on Colon Cancer Cells

PubMed Central

Sánchez-Camargo, Andrea del Pilar; García-Cañas, Virginia; Herrero, Miguel; Cifuentes, Alejandro; Ibáñez, Elena

2016-01-01

In the present work, four green processes have been compared to evaluate their potential to obtain rosemary extracts with in vitro anti-proliferative activity against two colon cancer cell lines (HT-29 and HCT116). The processes, carried out under optimal conditions, were: (1) pressurized liquid extraction (PLE, using an hydroalcoholic mixture as solvent) at lab-scale; (2) Single-step supercritical fluid extraction (SFE) at pilot scale; (3) Intensified two-step sequential SFE at pilot scale; (4) Integrated PLE plus supercritical antisolvent fractionation (SAF) at pilot scale. Although higher extraction yields were achieved by using PLE (38.46% dry weight), this extract provided the lowest anti-proliferative activity with no observed cytotoxic effects at the assayed concentrations. On the other hand, extracts obtained using the PLE + SAF process provided the most active rosemary extracts against both colon cancer cell lines, with LC50 ranging from 11.2 to 12.4 µg/mL and from 21.8 to 31.9 µg/mL for HCT116 and HT-29, respectively. In general, active rosemary extracts were characterized by containing carnosic acid (CA) and carnosol (CS) at concentrations above 263.7 and 33.9 mg/g extract, respectively. Some distinct compounds have been identified in the SAF extracts (rosmaridiphenol and safficinolide), suggesting their possible role as additional contributors to the observed strong anti-proliferative activity of CA and CS in SAF extracts. PMID:27941607

Comparative Study of Green Sub- and Supercritical Processes to Obtain Carnosic Acid and Carnosol-Enriched Rosemary Extracts with in Vitro Anti-Proliferative Activity on Colon Cancer Cells.

PubMed

Sánchez-Camargo, Andrea Del Pilar; García-Cañas, Virginia; Herrero, Miguel; Cifuentes, Alejandro; Ibáñez, Elena

2016-12-07

In the present work, four green processes have been compared to evaluate their potential to obtain rosemary extracts with in vitro anti-proliferative activity against two colon cancer cell lines (HT-29 and HCT116). The processes, carried out under optimal conditions, were: (1) pressurized liquid extraction (PLE, using an hydroalcoholic mixture as solvent) at lab-scale; (2) Single-step supercritical fluid extraction (SFE) at pilot scale; (3) Intensified two-step sequential SFE at pilot scale; (4) Integrated PLE plus supercritical antisolvent fractionation (SAF) at pilot scale. Although higher extraction yields were achieved by using PLE (38.46% dry weight), this extract provided the lowest anti-proliferative activity with no observed cytotoxic effects at the assayed concentrations. On the other hand, extracts obtained using the PLE + SAF process provided the most active rosemary extracts against both colon cancer cell lines, with LC 50 ranging from 11.2 to 12.4 µg/mL and from 21.8 to 31.9 µg/mL for HCT116 and HT-29, respectively. In general, active rosemary extracts were characterized by containing carnosic acid (CA) and carnosol (CS) at concentrations above 263.7 and 33.9 mg/g extract, respectively. Some distinct compounds have been identified in the SAF extracts (rosmaridiphenol and safficinolide), suggesting their possible role as additional contributors to the observed strong anti-proliferative activity of CA and CS in SAF extracts.

[Analysis of supercritical fluid extracts of Radix caulophylli with gas chromatography-mass spectrometry].

PubMed

Wang, Si-Cen; Chen, Qin-Hua; Wei, Yao-Yuan; Li, Han-Wen; He, Lang-Chong

2007-05-01

To analyze the constituents in supercritical fluid CO2 extraction (SFE-CO2) of Radix caulophylli, the Radix caulophylli was extracted with SFE-CO2, and analyzed by gas chromatography-mass spectrometry (GC-MS). The GC-MS analysis with a DB-5MS capillary column (30 mm x 0.32 mm ID, 0.25 microm film thickness) was used. The inlet temperature was maintained at 280 degrees C. The column oven was held at 80 degrees C for 2 min, then programmed from 80 to 280 degrees C at 5 degrees C x min(-1) and, finally, held for 4 min. Helium at a constant flow rate of 2.0 mL x min(-1) was used as the carrier gas. The mass spectrometry conditions were as follows: ionization energy, 70 eV; ion source temperature, 200 degrees C. The mass selective detector was operated in the TIC mode (m/z was from 40 - 500). For the first time 49 peaks were separated and identified, the compounds were quantitatively determined by normalization method, and the identified compounds represent 97.44% of total GC peak areas. Viz, n-hexadecanoic acid (31.4%), (E, E) -9, 12-octadecadienoic acid (26.54%), (Z)-7-tetradecenal (9.4%), hexadecenoic acid (3.23%), 10-undecenal (3.22%), octadecanoic acid (2.25%), and caulophylline (1.76%) etc. The results will provide important foundation for understanding the constituents and further exploitation of Radix caulophylli.

Comparison of different extraction procedures for the comprehensive characterization of bioactive phenolic compounds in Rosmarinus officinalis by reversed-phase high-performance liquid chromatography with diode array detection coupled to electrospray time-of-flight mass spectrometry.

PubMed

Borrás Linares, I; Arráez-Román, D; Herrero, M; Ibáñez, E; Segura-Carretero, A; Fernández-Gutiérrez, A

2011-10-21

In the present work, a comparative study between two environmentally friendly and selective extraction techniques, such as supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE) have been carried out focusing in the bioactive phenolic compounds present in Rosmarinus officinalis. For the analysis of the SFE and PLE extracts, a new methodology for qualitative characterization has been developed, based on the use of reversed-phase high-performance liquid chromatography (RP-HPLC), equipped with two different detection systems coupled in series: diode array detector (DAD) and time of flight mass spectrometry (TOF-MS) detector connected via an electrospray ionization interface (ESI). The use of a small particle size C(18) column (1.8 μm) provided a great resolution and made possible the separation of several isomers. Moreover, UV-visible spectrophotometry is a valuable tool for identifying the class of phenolic compounds, whereas MS data enabled to structurally characterize the compounds present in the extracts. The applied methodology was useful for the determination of many well-known phenolic compounds present in R. officinalis, such as carnosol, carnosic acid, rosmadial, rosmanol, genkwanin, homoplantaginin, scutellarein, cirsimaritin and rosmarinic acid, as well as other phenolic compounds present in other species belonging to Lamiaceae family. Copyright © 2011 Elsevier B.V. All rights reserved.

Supercritical fluid extraction of 13-cis retinoic acid and its photoisomers from selected pharmaceutical dosage forms.

PubMed

Simmons, B R; Chukwumerije, O; Stewart, J T

1997-11-01

13-Cis retinoic acid (Accutane) was extracted from a cream, gel, capsule and beadlet dosage from using supercritical carbon dioxide modified with 5% methanol as the mobile phase. The pump pressure and the extraction chamber and restrictor temperature were experimentally optimized at 325 atm and 45 degrees C, respectively. A 2.5-min static and 5-min dynamic extraction time were used. The supercritical fluid extraction (SFE) eluent was trapped in methanol, injected into the high-performance liquid chromatographic (HPLC) system, and quantitated by ultraviolet detection at 360 nm. Application of the SFE method to spiked placebo dosage forms gave 13-cis retinoic acid recoveries of 98.8, 98.9, 98.8 and 100% for the cream, gel, capsule and beadlet, respectively, with R.S.D.s in the range 0.6-0.9% (n = 4). Inter-day percent error and precision of the extraction were 1.1-2.0 and 0.2-2.4% (n = 3), respectively, and intra-day percent error and precision were 1.0-3.0 and 0.3-2.1% (n = 8), respectively. Percent error and precision data for spiked celite samples in the 0.05-1.0 microgram ml-1 range were 0.59-4.75 and 1.8-2.1% (n = 3), respectively. The extraction method was applied to commercial 13-cis retinoic acid dosage forms and the results compared to unextracted samples. Linear regression analysis of concentration versus peak height gave a correlation coefficient of 0.9991 with a slope of 7.468 and a y-intercept of 0.1923. The percent error and precision data were 1.3-5.3 and 0.2-1.5% (n = 4), respectively. The photoisomers of 13-cis retinoic acid were also extracted with the method and recoveries of 90.4-92.4% with R.S.D.s of 1.5-3.4% were obtained (n = 4).

Characterization via liquid chromatography coupled to diode array detector and tandem mass spectrometry of supercritical fluid antioxidant extracts of Spirulina platensis microalga.

PubMed

Mendiola, Jose A; Marín, Francisco R; Hernández, S Francisco; Arredondo, Bertha O; Señoráns, F Javier; Ibañez, Elena; Reglero, Guillermo

2005-06-01

Spirulina platensis microalga has been extracted on a pilot scale plant using supercritical fluid extraction (SFE) under various extraction conditions. The extraction yield and the antioxidant activity of the extracts were evaluated in order to select those extracts with both the highest antioxidant capacity and a good extraction yield. These extracts were characterized using LC coupled to diode array detection (DAD) and LC coupled to mass spectrometry (MS) with two different interfaces, atmospheric pressure chemical ionization (APCI) and electrospray (ESI) which allowed us to perform tandem MS by using an ion trap analyzer. The best extraction conditions were as follows: CO2 with 10% of modifier (ethanol) as extraction solvent, 55 degrees C (extraction temperature) and 220 bar (extraction pressure). Fractionation was achieved by cascade depressurization providing two extracts with different activity and chemical composition. Several compounds have been identified in the extracts, corresponding to different carotenoids previously identified in Spirulina platensis microalga along with chlorophyll a and some degradation products. Also, the structure of some phenolic compounds could be tentatively identified. The antioxidant activity of the extracts could be attributed to some of the above mentioned compounds.

Development of porous structured polyvinyl alcohol/zeolite/carbon composites as adsorbent

NASA Astrophysics Data System (ADS)

Laksmono, J. A.; Sudibandriyo, M.; Saputra, A. H.; Haryono, A.

2017-05-01

Adsorption is a separation process that has higher energy efficiency than others. Analyzing the nature of the adsorbate and the selection of suitable adsorbent are key success in adsorption. The performance of the adsorbent can be modified either physically or chemically to obtain the efficiency and effectiveness of the adsorption, this can be facilitated by using a composite adsorbent. In this study, we have conducted the preparation process of a polyvinyl alcohol (PVA)/zeolite/carbon composites. The resulting adsorbent composites are dedicated for ethanol - water dehydration proposes. The composites were prepared using cross-linked polymerization method followed by supercritical fluid extraction (SFE) to obtain the porous structured upon drying process. The characterization of the functional groups and morphology were performed by using Fourier Transform Infra-Red (FTIR) and Scanning Electron Microscopy (SEM), respectively. The FTIR analysis showed that composite prepared by SFE method formed hydrogen bonding confirmed by the appearance of peaks at 2950 - 3000 cm-1 compared to composite without SFE method, whereas, the results of SEM study showed the formation of three layered structures. On basis of the obtained results, it can be shown that PVA/zeolite/carbon has high potential to be develop further as an adsorbent composite.

Supercritical Fluid Chromatography/Fourier Transform Infrared Spectroscopy Of Food Components

NASA Astrophysics Data System (ADS)

Calvey, Elizabeth M.; Page, Samuel W.; Taylor, Larry T.

1989-12-01

Supercritical fluid (SF) technologies are being investigated extensively for applications in food processing. The number of SF-related patents issued testifies to the level of interest. Among the properties of materials at temperatures and pressures above their critical points (supercritical fluids) is density-dependent solvating power. Supercritical CO2 is of particular interest to the food industry because of its low critical temperature (31.3°C) and low toxicity. Many of the components in food matrices react or degrade at elevated temperatures and may be adversely affected by high temperature extractions. Likewise, these components may not be amenable to GC analyses. Our SF research has been in the development of methods employing supercritical fluid chromatography (SFC) and extraction (SFE) coupled to a Fourier transform infrared (FT-IR) spectrometer to investigate food composition. The effects of processing techniques on the isomeric fatty acid content of edible oils and the analysis of lipid oxidation products using SFC/FT-IR with a flow-cell interface are described.

Geochemical evaluation of Niger Delta sedimentary organic rocks: a new insight

NASA Astrophysics Data System (ADS)

Akinlua, Akinsehinwa; Torto, Nelson

2011-09-01

A geochemical evaluation of Niger Delta organic matter was carried out using supercritical fluid extraction (SFE) sample preparation procedure. Comparison of geochemical significance of gas chromatographic data of rock extracts of SFE with those of Soxhlet extraction method from previous studies was made in order to establish the usefulness of SFE in geochemical exploration. The assessment of geochemical character of the rock samples from the comparison and interpretation of other geochemical parameters were used to give more insights into understanding the source rocks characteristics of onshore and shelf portions of the Niger Delta Basin. The results of the gas chromatographic (GC) analysis of the rock extracts across the lithostratigraphic units show that Pr/Ph, Pr/nC17, Pr/nC18, CPI and odd/even preference ranged from 0.07 to 12.39, 0.04 to 6.66, 0.05 to 13.80, 0.12 to 8.4 and 0.06 to 8.12, respectively. The Rock-Eval pyrolysis data and geochemical ratios and parameters calculated from the GC data showed that most of the samples are mature and have strong terrestrial provenance while a few samples have strong marine provenance. The few marine source rocks are located in the deeper depth horizon. Pr/Ph and standard geochemical plots indicate that most of samples were derived from organic matter deposited in less reducing conditions, i.e. more of oxidizing conditions while a few samples have predominantly influence of reducing conditions. The results of trace metal analysis of older samples from Agbada Formation also indicate marine and mixed organic matter input deposited in less reducing conditions. The results obtained in this study are comparable with those obtained from previous studies when Soxhlet extraction method was used and also indicated the presence of more than one petroleum systems in the Niger Delta.

Analysis of particulate polycyclic aromatic hydrocarbons by on-line coupled supercritical fluid extraction-liquid chromatography-gas chromatography-mass spectrometry

NASA Astrophysics Data System (ADS)

Shimmo, Masahiko; Adler, Heidi; Hyötyläinen, Tuulia; Hartonen, Kari; Kulmala, Markku; Riekkola, Marja-Liisa

An on-line supercritical fluid extraction-liquid chromatography-gas chromatography-mass spectrometry (SFE-LC-GC-MS) method was developed for the analysis of the particulate polycyclic aromatic hydrocarbons (PAHs). The limits of detection of the system for the quantification standards were in the range of 0.25-0.57 ng, while the limits of determinations for filter samples varied from 0.02 to 0.04 ng m -3 (24 h sampling). The linearity was excellent from 5 to 300 ng ( R2>0.967). The analysis could be carried out in a closed system without tedious manual sample pretreatment and with no risk of errors by contamination or loss of the analytes. The results of the SFE-LC-GC-MS method were comparable with those for Soxhlet and shake-flask extractions with GC-MS. The new method was applied to the analysis of PAHs collected by high-volume filter in the Helsinki area to study the seasonal trend of the concentrations. The individual PAH concentrations varied from 0.015 to more than 1 ng m -3, while total PAH concentrations varied from 0.81 to 5.68 ng m -3. The concentrations were generally higher in winter than in summer. The mass percentage of the total PAHs in total suspended particulates ranged from 2.85×10 -3% in July to 15.0×10 -3% in December. Increased emissions in winter, meteorological conditions, and more serious artefacts during the sampling in summer season may explain the concentration profiles.

Impacts of Extraction Methods in the Rapid Determination of Atrazine Residues in Foods using Supercritical Fluid Chromatography and Enzyme-Linked Immunosorbent Assay: Microwave Solvent vs. Supercritical Fluid Extractions

PubMed Central

El-Saeid, Mohamed H.; Kanu, Ijeoma; Anyanwu, Ebere C.; Saleh, Mahmoud A.

2005-01-01

It is an accepted fact that many food products that we eat today have the possibility of being contaminated by various chemicals used from planting to processing. These chemicals have been shown to cause illnesses for which some concerned government agencies have instituted regulatory mechanisms to minimize the risks and the effects on humans. It is for these concerns that reliable and accurate rapid determination techniques are needed to effect proper regulatory standards for the protection of people's nutritional health. This paper, therefore, reports the comparative evaluation of the extraction methods in the determination of atrazine (commonly used in agricultural as a herbicide) residues in foods using supercritical fluid chromatography (SFC) and enzyme-linked immunosorbent assay (ELISA) techniques. Supercritical fluid extraction (SFE) and microwave solvent extraction (MSE) methods were used to test samples of frozen vegetables, fruit juice, and jam from local food markets in Houston. Results showed a high recovery percentage of atrazine residues using supercritical fluid coupled with ELISA and SFC than with MSE. Comparatively, however, atrazine was detected 90.9 and 54.5% using SFC and ELISA techniques, respectively. ELISA technique was, however, less time consuming, lower in cost, and more sensitive with low detection limit of atrazine residues than SFC technique. PMID:15674445

Analysis of volatile secondary metabolites from Colombian Xylopia aromatica (Lamarck) by different extraction and headspace methods and gas chromatography.

PubMed

Stashenko, Elena E; Jaramillo, Beatriz E; Martínez, Jairo René

2004-01-30

Hydrodistillation (HD), simultaneous distillation-solvent extraction (SDE), microwave-assisted hydrodistillation (MWHD), and supercritical fluid (CO2) extraction (SFE), were employed to isolate volatile secondary metabolites from Colombian Xylopia aromatica (Lamarck) fruits. Static headspace (S-HS), simultaneous purge and trap (P&T) in solvent (CH2Cl2), and headspace (HS) solid-phase microextraction (SPME) were utilised to obtain volatile fractions from fruits of X. aromatica trees, which grow wild in Central and South America, and are abundant in Colombia. Kováts indices, mass spectra or standard compounds, were used to identify more than 50 individual components in the various volatile fractions. beta-Phellandrene was the main component found in the HD and MWHD essential oils, SDE and SFE extracts (61, 65, 57, and ca. 40%, respectively), followed by beta-myrcene (9.1, 9.3, 8.2 and 5.1%), and alpha-pinene (8.1, 7.3, 8.1 and 5.9%). The main components present in the volatile fractions of the X. aromatica fruits, isolated by S-HS, P&T and HS-SPME were beta-phellandrene (53.8, 35.7 and 39%), beta-myrcene (13.3, 12.3 and 10.1%), p-mentha-1(7),8-diene (7.1, 10.6 and 10.4%), alpha-phellandrene (2.2, 5.0 and 6.4%), and p-cymene (2.2,4.7 and 4.4%), respectively.

Anti-rotavirus effects by combination therapy of stevioside and Sophora flavescens extract.

PubMed

Alfajaro, Mia Madel; Rho, Mun-Chual; Kim, Hyun-Jeong; Park, Jun-Gyu; Kim, Deok-Song; Hosmillo, Myra; Son, Kyu-Yeol; Lee, Ju-Hwan; Park, Sang-Ik; Kang, Mun-Il; Ryu, Young Bae; Park, Ki Hun; Oh, Hyun-Mee; Lee, Seung Woong; Park, Su-Jin; Lee, Woo Song; Cho, Kyoung-Oh

2014-06-01

Anti-rotaviral activities of Sophora flavescens extract (SFE) and stevioside (SV) from Stevia rebaudiana Bertoni either singly or in various combinations were examined in vitro and in vivo using a porcine rotavirus G5[P7] strain. Combination of SFE and SV inhibited in vitro virus replication more efficiently than each single treatment. In the piglet model, SV had no effect on rotavirus enteritis, whereas SFE improved but did not completely cure rotaviral enteritis. Interestingly, combination therapy of SFE and SV alleviated diarrhea, and markedly improved small intestinal lesion score and fecal virus shedding. Acute toxicity tests including the piglet lethal dose 50, and body weight, organ weight and pathological changes for the combination therapy did not show any adverse effect on the piglets. These preliminary data suggest that the combination therapy of SV and SFE is a potential curative medication for rotaviral diarrhea in pigs. Determination of the efficacy of this combination therapy in other species including humans needs to be addressed in the future. Copyright © 2014 Elsevier Ltd. All rights reserved.

Muscle-protective effects of Schisandrae Fructus extracts in old mice after chronic forced exercise.

PubMed

Kim, Ki-Young; Ku, Sae-Kwang; Lee, Ki-Won; Song, Chang-Hyun; An, Won G

2018-02-15

Schisandrae Fructus (SF), the dried fruit of Schisandra chinensis (Turcz.) Baill., is a well-known traditional herb used in Asia for enhancing physical work capacity as well as providing anti-stress and anti-inflammatory effects. Extracts of SF (SFe) have also been reported to increase skeletal muscle mass and inhibit muscle atrophy. We examined whether SFe had muscle-protective effects in old mice after chronic forced exercises, and, if so, relevant mechanisms. Ten-month-old aged male mice were divided into six groups. One group received no forced swimming after oral administration of distilled water (Intact); the other groups received forced swimming after administration of distilled water (SW), oxymetholone (OXY), or SFe at 500, 250 and 125mg/kg (SFe500, SFe250, and SFe125, respectively). Forced swimming was conducted for 2min at 30min after oral administration; the treatment was repeated for 28 days. Muscle thickness, weight, lean proportion, and strength were examined. The sampled muscles were subjected to histopathological and biochemical analyses. Plasma was examined by biochemical analyses. The thicknesses of the calf muscle and the sampled gastrocnemius and soleus, protein proportion and muscle strength increased significantly in the SW group versus Intact, and they were further increased in the SFe and OXY groups versus SW. The forced swimming in the SW group upregulated mRNA expression related to protein synthesis (Akt1, PI3K) and muscle growth (A1R, TRPV4), while it downregulated mRNAs related to protein degradation (atrogin-1, MuRF1) and muscle growth inhibitor (myostatin, SIRT1). The detected upregulation and downregulation were enhanced in the SFe groups. In addition, the SFe administration inhibited lipid peroxidation and reactive oxygen species, and accelerated activities of endogenous anti-oxidants and anti-oxidant enzymes. Plasma biochemistry showed decreases in creatine, creatine kinase and LDH in the SFe groups versus SW, suggesting muscle-protective effects of SFe. In the SFe groups versus SW, histopathological analyses revealed an increase in myofibre diameter, and immunohistochemistry showed increases in myofibres immunoreactive for ATPase and decreases in myofibres for apoptosis markers (caspase-3, PARP) and oxidative stress markers (NT, 4HNE, iNOS). Oral administration of SFe, especially SFe500, enhanced exercise-induced adaptive muscle strengthening in aged mice after forced swimming through anti-apoptotic and anti-oxidant effects, mediated via modulation of gene expression related to muscle synthesis or degradation. These results suggest that SFe may be helpful in improvement various muscle disorders as an adjuvant therapy to exercise-based remedies. Copyright © 2017 Elsevier B.V. All rights reserved.

Supercritical CO2 extract of Cinnamomum zeylanicum: chemical characterization and antityrosinase activity.

PubMed

Marongiu, Bruno; Piras, Alessandra; Porcedda, Silvia; Tuveri, Enrica; Sanjust, Enrico; Meli, Massimo; Sollai, Francesca; Zucca, Paolo; Rescigno, Antonio

2007-11-28

The volatile oil of the bark of Cinnamomum zeylanicum was extracted by means of supercritical CO2 fluid extraction in different conditions of pressure and temperature. Its chemical composition was characterized by GC-MS analysis. Nineteen compounds, which in the supercritical extract represented >95% of the oil, were identified. (E)-Cinnamaldehyde (77.1%), (E)-beta-caryophyllene (6.0%), alpha-terpineol (4.4%), and eugenol (3.0%) were found to be the major constituents. The SFE oil of cinnamon was screened for its biological activity about the formation of melanin in vitro. The extract showed antityrosinase activity and was able to reduce the formation of insoluble flakes of melanin from tyrosine. The oil also delayed the browning effect in apple homogenate. (E)-Cinnamaldehyde and eugenol were found to be mainly responsible of this inhibition effect.

[Extraction of 10-Deacetyl Baccatin by Supercritical CO2 from Taxus yunnanensis Branches and Leaves].

PubMed

Tang, Yang-qin; Li, Hai-chi; Huang, Wen-jie; Xiong, Yan; Ge, Fa-huan

2015-04-01

To study the supercritical CO2 fluids extraction (SFE) method to extract the components from Taxus yunnanensis. Medicinal meterials were extracted by supercritical CO2, and then purified by industrial chromatography. Using the extraction yield of 10-DAB as the index,single factor test was carried out to investigate the effect of co-solvent, extraction time, extraction pressure, extraction temperature, pressure and temperature of separation kettle I. Then orthogonal experiment was used to optimize the best extraction condition. The suitable extraction condition was as follows: the ratio of co-solvent (80% ethanol) amount and the madicinal materials was 3: 1, Separation kettle I pressure was 14 MPa, separation kettle I temperature was 40 °C, extraction pressure was 25 MPa, extraction temperature was 60 T and extraction time was 90 min. The extract was separated by industrial chromatographic and then crystallized. The supercritical CO2 extraction and purification process of 10-DAB were simple and feasible.

Comprehensive Review of Applicable Supercritical Fluid Extraction Research

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harvey, Scott; Wright, Cherylyn W.; Wright, Bob W.

2001-09-10

This comprehensive supercritical fluid extraction (SFE) literature review is divided into three major sections. The first section describes the electronic literature search details including the abstract service used and the different topics searched. This section also contains an overview of the seven search topics that yielded relevant references along with a brief synopsis of the most significant literature citations. These seven groupings are (1) chemical warfare agents; (2) explosives; (3) hazardous chemicals; (4) poisons, toxins and mycotoxins; (5) toxic (lethal) chemical and toxicants; (6) pesticides in soil; and (7) pesticides from plant and animal tissues. The second section contains tablesmore » of each of these groupings. Each of the seven tables contains entries for individual literature citations listed along with the specific compounds or compound classes that are addressed. The third section refers to the abstracts used in the literature search.« less

Quantitative Analysis of Bioactive Compounds from Aromatic Plants by Means of Dynamic Headspace Extraction and Multiple Headspace Extraction-Gas Chromatography-Mass Spectrometry.

PubMed

Omar, Jone; Olivares, Maitane; Alonso, Ibone; Vallejo, Asier; Aizpurua-Olaizola, Oier; Etxebarria, Nestor

2016-04-01

Seven monoterpenes in 4 aromatic plants (sage, cardamom, lavender, and rosemary) were quantified in liquid extracts and directly in solid samples by means of dynamic headspace-gas chromatography-mass spectrometry (DHS-GC-MS) and multiple headspace extraction-gas chromatography-mass spectrometry (MHSE), respectively. The monoterpenes were 1st extracted by means of supercritical fluid extraction (SFE) and analyzed by an optimized DHS-GC-MS. The optimization of the dynamic extraction step and the desorption/cryo-focusing step were tackled independently by experimental design assays. The best working conditions were set at 30 °C for the incubation temperature, 5 min of incubation time, and 40 mL of purge volume for the dynamic extraction step of these bioactive molecules. The conditions of the desorption/cryo-trapping step from the Tenax TA trap were set at follows: the temperature was increased from 30 to 300 °C at 150 °C/min, although the cryo-trapping was maintained at -70 °C. In order to estimate the efficiency of the SFE process, the analysis of monoterpenes in the 4 aromatic plants was directly carried out by means of MHSE because it did not require any sample preparation. Good linearity (r2) > 0.99) and reproducibility (relative standard deviation % <12) was obtained for solid and liquid quantification approaches, in the ranges of 0.5 to 200 ng and 10 to 500 ng/mL, respectively. The developed methods were applied to analyze the concentration of 7 monoterpenes in aromatic plants obtaining concentrations in the range of 2 to 6000 ng/g and 0.25 to 110 μg/mg, respectively. © 2016 Institute of Food Technologists®

Supercritical fluid extraction of ginger (Zingiber Officinale Var. Amarum) : Global yield and composition study

NASA Astrophysics Data System (ADS)

Fitriady, Muhammad Arifuddin; Sulaswatty, Anny; Agustian, Egi; Salahuddin, Aditama, Deska Prayoga Fauzi

2017-11-01

An experiment to observe the effect of temperature and time process in ginger rhizome-Supercritical Fluid Extraction (SFE) using CO2 as the solvent has been conducted. The ginger rhizome (Zingiber Officinale Var. Amarum) was washed, drained, sliced, sun-dried, and then stored in a sealed bag prior to usage. The temperature and time process variables are each 35, 40, 45°C and 2, 4, 6 hours respectively with the pressure variable are 3500, 4000, and 4500 psi. It is found that the highest yield (2.9%) was achieved using temperature of 40°C and pressure of 4500 psiwith the process time of 4 hours. However, using the curve-fitting method, it is suggested to use 42°C as the temperature and 5 hours, 7 minutes, and 30 seconds (5.125 Hours) as the time process to obtain the highest yield. The temperature changes will affect both solvent and vapor pressure of diluted compounds of the ginger which will influence the global yield and the composition of the extract. The three major components of the extract are curcumene, zingiberene, and β - sesquipellandrene,

Seasonal differences in the content of phenols and pigments in thalli of freshwater Cladophora glomerata and its habitat.

PubMed

Fabrowska, Joanna; Messyasz, Beata; Pankiewicz, Radosław; Wilińska, Patrycja; Łęska, Bogusława

2018-05-15

Polyphenols are chemicals that primarily inhibit the growth of various autotrophic organisms. The presence of these metabolites greatly boosts the ecological dominance of eg. Cladophora, which creates large surface mats. The main goal of our work was to quantify the phenol and polyphenols (allelopathic substances) secreted by the macroalgae as a result of exposure to biotic stress caused by competition. The research was carried out on the Cladophora glomerata biomass collected from two freshwater ecosystems located in Wielkopolska Region (Poland, Fig. 1): Oporzynskie Lake (N52° 55', E 17° 9') and Nielba River (N52˚48', E 17° 12'). Seasonal variability (May-October 2015) in the properties of C. glomerata mats in the river and lake ecosystem was also analyzed in relation to the physicochemical parameters of water. In addition, the content of pigments in the analyzed biomass was determined during the appearance of algae mats in water reservoirs. Biomass extraction was performed to determine the phenolic and carotenoid contents (chlorophyll and carotenoids) by using two extraction methods: microwave-assisted extraction (MAE) and supercritical fluid extraction (SFE). After isolation of the phenols from the thalli (mats) and the habitat, they were analyzed using the Folin-Ciocalteu method with some modifications, while the pigment content (chlorophyll and carotenoids) was evaluated by the spectrophotometric method Liechtenthaler (1987) with some variations. Analysis of the content of these components in algae extracts indicates that the tendency of changes in their contents was similar or the same. Growth and decrease of phenolic content (Cladophora T MAE and Cladophora T SFE) and pigments (MAE chlorophyll, SFE and MAE carotenoids) at the same time were independent of the insulation method used. The mats formed by C. glomerata on the surface of Lake Oporzyńskie were more stable and larger surface area than those on the Nielba River, which could explain differences in polyphenol concentrations in these two aquatic ecosystems. The results suggest a reduction in the secretion of phenolic compounds with an aging population of algae. Copyright © 2018 Elsevier Ltd. All rights reserved.

Optimization of Supercritical Fluid Extraction of Total Alkaloids, Peimisine, Peimine and Peiminine from the Bulb of Fritillaria thunbergii Miq, and Evaluation of Antioxidant Activities of the Extracts

PubMed Central

Ruan, Xiao; Yang, Li; Cui, Wen-Xia; Zhang, Men-Xing; Li, Zhao-Hui; Liu, Ben; Wang, Qiang

2016-01-01

Supercritical fluid extraction (SFE) was used to extract total alkaloids, peimisine, peimine and peiminine from the bulb of Fritillaria thunbergii Miq. The antioxidant capacity of the extracts was evaluated by DPPH radical scavenging activity (DPPH-RSA), ABTS radical scavenging activity (ABTS-RSA) and ferric reducing capacity (FRAP) assay. A central composite design (CCD) with four variables and five levels was employed for optimization of process parameters, and response surface plots were constructed in accordance with a second order polynomial model. Under optimal conditions of 3.0 h, 60.4 °C, 26.5 MPa and 89.3% ethanol, the highest yields were predicted to be 3.8 mg/g for total alkaloids, 0.5 mg/g for peimisine, 1.3 mg/g for peimine and 1.3 mg/g for peiminine, and the antioxidant capacity of extracts displayed EC50, DPPH value of 5.5 mg/mL, EC50, ABTS value of 0.3 mg/mL and FRAP value of 118.2 mg ascorbic acid equivalent (AAE)/100 g. PMID:28773648

Low-dose intrathecal fluorescein for diagnosis of cerebrospinal fluid rhinorrhea using the scanning fiber endoscope in the human nasal cavities

NASA Astrophysics Data System (ADS)

Hou, Vivian W.; Davis, Calvin G.; Davis, Greg E.; Seibel, Eric J.

2016-03-01

Intrathecal fluorescein (ITF) enhances detection of cerebrospinal fluid rhinorrhea (CSFR). Clinically administered doses fall in the range of 0.1ml to 0.5ml of 5% to 10% fluorescein (1.3×10-3M to 1.3×10-2M). Though uncommon, significant morbidities associated with high doses of fluorescein have been reported. High concentrations are necessary for white light visual assessment; in contrast, fluorescent imaging enhances signal contrast and requires lower ITF concentrations for visualization. The ultrathin and flexible, multimodal scanning fiber endoscope (SFE) can visualize nanomolar concentrations of fluorescein as pseudocolor over reflectance, video-rate imaging. The application of the SFE for CSFR detection was assessed in a cadaver study. Briefly, 10μM (1×10-5M) fluorescein, 100X-1000X less than the standard clinical dose, was injected intra-cranially into the epidural space through an orbital roof puncture. The resulting rhinorrhea was assessed with a conventional, rigid ENT scope and second with the SFE in both video reflectance and multimodal fluorescent imaging modes. Neither system could visualize the 10μM ITF during white light imaging however the nanomolar sensitive SFE visualized the rhinorrhea during fluorescent imaging. Despite the low concentration used, a target-to-background ratio of 5.6 +/- 2.7 was achieved. To demonstrate SFE guidance of CSFR detection and repair, de-identified patient computed tomography (CT) scans were used to generate 3D printed phantoms. Cases were selected for unique anatomical features and overall clinical difficulty as determined by an experienced ENT clinician (GED). The sensitivity and minimally invasive nature of the SFE provide a unique platform for enhancing diagnosis and monitoring interventions in surgical endoscopic approaches into the sinuses.

Preparative purification of the major anti-inflammatory triterpenoid esters from Marigold (Calendula officinalis).

PubMed

Hamburger, M; Adler, S; Baumann, D; Förg, A; Weinreich, B

2003-06-01

A method for the efficient preparative purification of faradiol 3-O-laurate, palmitate and myristate, the major anti-inflammatory triterpenoid esters in the flower heads of the medicinal plant Calendula officinalis has been developed. Gram quantities of the individual compounds were obtained with 96 to 98% purity by a combination of supercritical fluid extraction (SFE), normal-phase and reversed-phase column chromatography. During the work-up of the faradiol esters, accompanying minor compounds of the triterpene ester fraction were purified and identified by spectroscopic means as maniladiol 3-O-laurate and myristate.

Comparison of different extraction methods for the analysis of volatile secondary metabolites of Lippia alba (Mill.) N.E. Brown, grown in Colombia, and evaluation of its in vitro antioxidant activity.

PubMed

Stashenko, Elena E; Jaramillo, Beatriz E; Martínez, Jairo René

2004-01-30

Hydrodistillation (HD), simultaneous distillation solvent extraction (SDE), microwave-assisted hydrodistillation (MWHD), and supercritical fluid (CO2) extraction (SFE) were employed to isolate volatile secondary metabolites from fresh leaves and stems of Colombian Lippia alba (Mill.) N.E. Brown. Kovàts indices, mass spectra or standard compounds were used to identify around 40 components in the various volatile fractions. Carvone (40-57%) was the most abundant component, followed by limonene (24-37%), bicyclosesquiphellandrene (5-22%), piperitenone (1-2%), piperitone (ca. 1.0%), and beta-bourbonene (0.6-1.5%), in the HD, SDE, MWHD, and SFE volatile fractions. Static headspace (S-HS), simultaneous purge and trap in solvent (CH2Cl2) (P&T), and headspace solid-phase microextraction (HS-SPME) were used to sample volatiles from fresh L. alba stems and leaves. The main components isolated from the headspace of the fresh plant material were limonene (27-77%), carvone (14-30%), piperitone (0.3-0.5%), piperitenone (ca. 0.4%), and beta-bourbonene (0.5-6.5%). The in vitro antioxidant activity of L. alba essential oil, obtained by hydrodistillation was evaluated by determination of hexanal, the main carbonyl compound released by linoleic acid subjected to peroxidation (1 mm Fe2+, 37 degrees C, 12 h), and by quantification of this acid as its methyl ester. Under the same conditions, L. alba HD-essential oil and Vitamin E exhibited similar antioxidant effects.

Comparative analysis of the oil and supercritical CO(2) extract of Schinus molle L. growing in Yemen.

PubMed

Ali, Nasser A Awadh; Marongiu, Bruno; Piras, Alessandra; Porcedda, Silvia; Falconieri, Danilo; Al-Othman, Al-Husein M R

2011-08-01

In this study, we report the preliminary data on the chemical composition of Yemeni Schinus molle L. volatile oil obtained by supercritical extraction with carbon dioxide (40°C and 90 bar), SFE, and by hydrodistillation (HD). The composition of the volatile oil has been analysed by GC and GC-MS. The content of the major constituents in the oils from leaves varied in the following ranges: germacrene D 3.7% in SFE and 16.7% in HD; β-caryophyllene 19.1% in SFE and 13.5% in HD. The amount of monoterpenes constituted 4%, in all the analysed samples, while the number of sesquiterpenes was 44% in supercritical and 67% in HD oil. Some compounds were not identified by GC-MS and it will require further analysis using other analytical techniques.

Influence of different extraction methods on the yield and linalool content of the extracts of Eugenia uniflora L.

PubMed

Galhiane, Mário S; Rissato, Sandra R; Chierice, Gilberto O; Almeida, Marcos V; Silva, Letícia C

2006-09-15

This work has been developed using a sylvestral fruit tree, native to the Brazilian forest, the Eugenia uniflora L., one of the Mirtaceae family. The main goal of the analytical study was focused on extraction methods themselves. The method development pointed to the Clevenger extraction as the best yield in relation to SFE and Soxhlet. The SFE method presented a good yield but showed a big amount of components in the final extract, demonstrating low selectivity. The essential oil extracted was analyzed by GC/FID showing a large range of polarity and boiling point compounds, where linalool, a widely used compound, was identified. Furthermore, an analytical solid phase extraction method was used to clean it up and obtain separated classes of compounds that were fractionated and studied by GC/FID and GC/MS.

Supercritical fluid extraction and ultra performance liquid chromatography of respiratory quinones for microbial community analysis in environmental and biological samples.

PubMed

Hanif, Muhammad; Atsuta, Yoichi; Fujie, Koichi; Daimon, Hiroyuki

2012-03-05

Microbial community structure plays a significant role in environmental assessment and animal health management. The development of a superior analytical strategy for the characterization of microbial community structure is an ongoing challenge. In this study, we developed an effective supercritical fluid extraction (SFE) and ultra performance liquid chromatography (UPLC) method for the analysis of bacterial respiratory quinones (RQ) in environmental and biological samples. RQ profile analysis is one of the most widely used culture-independent tools for characterizing microbial community structure. A UPLC equipped with a photo diode array (PDA) detector was successfully applied to the simultaneous determination of ubiquinones (UQ) and menaquinones (MK) without tedious pretreatment. Supercritical carbon dioxide (scCO(2)) extraction with the solid-phase cartridge trap proved to be a more effective and rapid method for extracting respiratory quinones, compared to a conventional organic solvent extraction method. This methodology leads to a successful analytical procedure that involves a significant reduction in the complexity and sample preparation time. Application of the optimized methodology to characterize microbial communities based on the RQ profile was demonstrated for a variety of environmental samples (activated sludge, digested sludge, and compost) and biological samples (swine and Japanese quail feces).

Structural characterization and physicochemical properties of protein extracted from soybean meal assisted by steam flash-explosion with dilute acid soaking.

PubMed

Zhang, Yanpeng; Yang, Ruijin; Zhang, Weinong; Hu, Zhixiong; Zhao, Wei

2017-03-15

The aim of this work was to analyze the influence of steam flash-explosion (SFE) with dilute acid soaking pretreatment on the structural characteristics and physiochemical properties of protein from soybean meal (SBM). The pretreatment led to depolymerisation of soy protein isolate (SPI) and formation of new protein aggregation through non-disulfide covalent bonds, which resulted in broader MW distribution of SPI. The analysis of CD spectroscopy showed that the SFE treatment induced minor changes in secondary structure, however, the intrinsic tryptophan fluorescence revealed that acid soaking and SFE treatment pronouncedly altered the tertiary structure of SPI. The protein zeta potential was shown to be increased after SFE treatment attributed to the changes in protein structure and the covalent coupling between carbohydrate and protein. These results contribute to clarifying the mechanisms of the effect of pretreatment on SPI structure, thus moving further toward implementing SFE in the processing chain of SPI. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Orthogonal experiment using SFE-CO2 in extraction of essential oil from fresh Houttuynia cordata and analysis of essential oil by GC-MS].

PubMed

Meng, Jiang; Dong, Xiao-ping; Zhou, Yi-sheng; Jiang, Zhi-hong; Leung, Kelvin Sze-Yin; Zhao, Zhong-zhen

2007-02-01

To optimize the extraction procedure of essential oil from H. cordata using the SFE-CO2 and analyze the chemical composition of the essential oil. The extraction procedure of essential oil from fresh H. cordata was optimized with the orthogonal experiment. Essential oil of fresh H. cordata was analysed by GC-MS. The optimize preparative procedure was as follow: essential oil of H. cordata was extracted at a temperature of 35 degrees C, pressure of 15,000 kPa for 20 min. 38 chemical components were identified and the relative contents were quantified. The optimum preparative procedure is reliable and can guarantee the quality of essential oil.

Selective enrichment in bioactive compound from Kniphofia uvaria by super/subcritical fluid extraction and centrifugal partition chromatography.

PubMed

Duval, Johanna; Destandau, Emilie; Pecher, Virginie; Poujol, Marion; Tranchant, Jean-François; Lesellier, Eric

2016-05-20

Nowadays, a large portion of synthetic products (active cosmetic and therapeutic ingredients) have their origin in natural products. Kniphofia uvaria is a plant from Africa which has proved in the past by in-vivo tests an antioxidant activity due to compounds present in roots. Recently, we have observed anthraquinones in K. uvaria seeds extracts. These derivatives are natural colorants which could have interesting bioactive potential. The aim of this study was to obtain an extract enriched in anthraquinones from K. uvaria seeds which mainly contains glycerides. First, the separation of the seed compounds was studied by using supercritical fluid chromatography (SFC) in the goal to provide a rapid quantification method of these bioactive compounds. A screening of numerous polar stationary phases was achieved for selecting the most suited phase to the separation of the four anthraquinones founded in the seeds. A gradient elution was optimized for improving the separation of the bioactive compounds from the numerous other families of major compounds of the extracts (fatty acids, di- and triglycerides). Besides, a non-selective and green Supercritical Fluid Extraction (SFE) with pure CO2 was applied to seeds followed by a Centrifugal Partition Chromatography (CPC). The CPC system was optimized by using the Arizona phase system, to enrich the extract in anthraquinones. Two systems were selected to isolate the bioactive compounds from the oily extract with varied purity target. The effect of the injection mode for these very viscous samples was also studied. Finally, in order to directly apply a selective process of extraction to the seeds, the super/subcritical fluid extraction was optimized to increase the anthraquinone yield in the final extract, by studying varied modifier compositions and nature, as well as different temperatures and backpressures. Conditions suited to favour an enrichment factor bases on the ratio of anthraquinone and trilycerides extracted are described. Copyright © 2016 Elsevier B.V. All rights reserved.

SELECTIVE EXTRACTION OF OXYGENATES FROM SAVORY AND PEPPERMINT USING SUBCRITICAL WATER. (R825394)

EPA Science Inventory

The yields of oxygenated and non-oxygenated flavour and fragrance compounds from savory (Satureja hortensis) and peppermint (Mentha piperita) were compared using subcritical water extraction, supercritical carbon dioxide extraction (SFE) and hydrodistillation. Extraction rates wi...

Antioxidant Activity of Mulberry Fruit Extracts

PubMed Central

Arfan, Muhammad; Khan, Rasool; Rybarczyk, Anna; Amarowicz, Ryszard

2012-01-01

Phenolic compounds were extracted from the fruits of Morus nigra and Morus alba using methanol and acetone. The sugar-free extracts (SFEs) were prepared using Amberlite XAD-16 column chromatography. All of the SFEs exhibited antioxidant potential as determined by ABTS (0.75–1.25 mmol Trolox/g), DPPH (2,2-diphenyl-1-picrylhydrazyl) (EC50 from 48 μg/mL to 79 μg/mL), and reducing power assays. However, a stronger activity was noted for the SFEs obtained from Morus nigra fruits. These extracts also possessed the highest contents of total phenolics: 164 mg/g (methanolic SFE) and 173 mg/g (acetonic SFE). The presence of phenolic acids and flavonoids in the extracts was confirmed using HPLC method and chlorogenic acid and rutin were found as the dominant phenolic constituents in the SFEs. PMID:22408465

[Research of the essential oil of Plumeria rubra var. actifolia from Laos by supercritical carbon dioxide extraction].

PubMed

Xiao, Xin-Yu; Cui, Long-Hai; Zhou, Xin-Xin; Wu, Yan; Ge, Fa-Huan

2011-05-01

The orthogonal test and the supercritical carbon dioxide fluid extraction were used for optimizing the extraction of the essential oil from Plumeria rubra var. actifolia for the first time. Compared with the steam distillation, the optimal operation parameter of extraction was as follows: extraction pressure 25 MPa, extraction temperature 45 degrees C; separator I pressure 12 MPa, separator I temperature 55 degrees C; separator II pressure 6 MPa, separator II temperature 30 degrees C. Under this condition the yield of the essential oil was 5.8927%. The components were separated and identified by GC-MS. 53 components of Plumeria rubra var. actifolia measured by SFE method were identified and determined by normalization method. The main components were 1, 6, 10-dodecatrien-3-ol, 3, 7, 11-trimethyl, benzoic acid, 2-hydroxy-, phenylmethyl ester, 1, 2-benzenedicarboxylic acid, bis(2-methylpropyl) ester,etc.. 1, 2-Benzenedicarboxylic acid, bis (2-methylpropyl) este. took up 66.11% of the total amount, and there was much difference of the results from SD method.

Compositional and sensory differences of products of sweet-cream and whey buttermilk produced by microfiltration, diafiltration, and supercritical CO2.

PubMed

Olabi, A; Jinjarak, S; Jiménez-Flores, R; Walker, J H; Daroub, Hamza

2015-06-01

The objectives of this work were to assess the compositional properties and sensory characteristics of ingredients produced by treating sweet-cream and whey-cream buttermilks with microfiltration (MF), diafiltration (DF), and supercritical CO2 (SFE) extraction. Sweet-cream buttermilk (CBM) and buttermilk resulting from churning the residual fat from whey processing (whey buttermilk, WBM) were used. Using MF or microfiltration followed by diafiltration (MF-DF), we obtained resulting retentates that were dried and then were subjected to SFE treatment. Control buttermilks, SFE resulting products, and MF and MF-DF SFE and all treated retentates products totaled 16 samples (2 types×4 treatments×2 batches). Eleven trained panelists assessed samples using descriptive analysis. Sweet-cream buttermilk was higher in protein and lactose, whereas the WBM had similar total protein, mainly β-LG and α-LA but very low lactose. The resulting samples in order of concentration for fat and lactose were control samples>SFE treated>MF treated>DF=MF-SFE and DF-SFE. Sodium dodecyl sulfate-PAGE protein profiling showed negligible casein for WBM versus CBM and less whey proteins for CBM versus WBM, as expected. Whey buttermilk was more yellow, salty, sour, and rancid than CBM. Regarding the treatments, significant differences were obtained on homogeneity, opacity, rancid odor, cardboard and sour flavors, sweet and salty tastes, viscosity, and mouthcoating, where SFE-treated samples showed lowest rancid odor and cardboard flavor. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Comparison of the Anti-Inflammatory Activities of Supercritical Carbon Dioxide versus Ethanol Extracts from Leaves of Perilla frutescens Britt. Radiation Mutant.

PubMed

Jin, Chang Hyun; Park, Han Chul; So, Yangkang; Nam, Bomi; Han, Sung Nim; Kim, Jin-Baek

2017-02-17

In this study, we aimed to compare supercritical carbon dioxide extraction and ethanol extraction for isoegomaketone (IK) content in perilla leaf extracts and to identify the optimal method. We measured the IK concentration using HPLC and inflammatory mediators in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells from the extracts. The IK concentration was 10-fold higher in perilla leaf extracts by supercritical carbon dioxide extraction (SFE) compared with that in perilla leaf extracts by ethanol extraction (EE). When the extracts were treated in LPS-induced RAW 264.7 cells at 25 μg/mL, the SFE inhibited the expression of inflammatory mediators such as nitric oxide (NO), monocyte chemoattractant protein-1 (MCP-1), interleutkin-6 (IL-6), interferon-β (IFN-β), and inducible nitric oxide synthase (iNOS) to a much greater extent compared with EE. Taken together, supercritical carbon dioxide extraction is considered the optimal process for obtaining high IK content and anti-inflammatory activities in leaf extracts from the P. frutescens Britt. radiation mutant.

Use of advanced techniques for the extraction of phenolic compounds from Tunisian olive leaves: phenolic composition and cytotoxicity against human breast cancer cells.

PubMed

Taamalli, Amani; Arráez-Román, David; Barrajón-Catalán, Enrique; Ruiz-Torres, Verónica; Pérez-Sánchez, Almudena; Herrero, Miguel; Ibañez, Elena; Micol, Vicente; Zarrouk, Mokhtar; Segura-Carretero, Antonio; Fernández-Gutiérrez, Alberto

2012-06-01

A comparison among different advanced extraction techniques such as microwave-assisted extraction (MAE), supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE), together with traditional solid-liquid extraction, was performed to test their efficiency towards the extraction of phenolic compounds from leaves of six Tunisian olive varieties. Extractions were carried out at the best selected conditions for each technique; the obtained extracts were chemically characterized using high-performance liquid chromatography (HPLC) coupled to electrospray time-of-flight mass spectrometry (ESI-TOF-MS) and electrospray ion trap tandem mass spectrometry (ESI-IT-MS(2)). As expected, higher extraction yields were obtained for PLE while phenolic profiles were mainly influenced by the solvent used as optimum in the different extraction methods. A larger number of phenolic compounds, mostly of a polar character, were found in the extracts obtained by using MAE. Best extraction yields do not correlate with highest cytotoxic activity against breast cancer cells, indicating that cytotoxicity is highly dependent on the presence of certain compounds in the extracts, although not exclusively on a single compound. Therefore, a multifactorial behavior is proposed for the anticancer activity of olive leaf compounds. Copyright © 2012 Elsevier Ltd. All rights reserved.

Supercritical carbon dioxide extraction of electrolyte from spent lithium ion batteries and its characterization by gas chromatography with chemical ionization

NASA Astrophysics Data System (ADS)

Mönnighoff, Xaver; Friesen, Alex; Konersmann, Benedikt; Horsthemke, Fabian; Grützke, Martin; Winter, Martin; Nowak, Sascha

2017-06-01

The aging products of the electrolyte from a commercially available state-of-the-art 18650-type cell were investigated. During long term cycling a huge difference in their performance and lifetime at different temperatures was observed. By interpretation of a strong capacity fading of cells cycled at 20 °C compared to cells cycled at 45 °C a temperature depending aging mechanism was determined. To investigate the influence of the electrolyte on this fading, the electrolyte was extracted by supercritical fluid extraction (SFE) and then analyzed by gas chromatography (GC) with electron impact (EI) ionization and mass selective detection. To obtain more information with regard to the identification of unknown decomposition products further analysis with positive chemical ionization (PCI) and negative chemical ionization (NCI) was performed. 17 different volatile organic aging products were detected and identified. So far, seven of them were not yet known in literature and several formation pathways were postulated taking previously published literature into account.

δ 13C of free and macromolecular aromatic structures in the murchison meteorite

NASA Astrophysics Data System (ADS)

Sephton, M. A.; Pillinger, C. T.; Gilmour, I.

1998-05-01

Analyses of the organic compounds in the Murchison meteorite have led to a greater understanding of the nature of extraterrestrial organic materials. However, the relationship between low and high molecular weight material remains poorly understood. To investigate this relationship, untreated Murchison was subjected to supercritical fluid extraction (SFE) to obtain the free organic components in the meteorite. Toluene and other volatile aromatic hydrocarbons dominated the extract, and the carbon isotopic composition of these molecules was determined by gas chromatography-isotope ratio-mass spectrometry (GCIRMS). δ 13C values of the aromatic hydrocarbons ranged from -28.8 to -5.8‰. These compounds displayed a 13C-enrichment with increasing carbon number suggesting an origin by cracking. The high molecular weight organic material in the meteorite was isolated and subjected to hydrous pyrolysis. This procedure produced a number of aromatic products, the majority of which were volatile aromatic hydrocarbons, particularly toluene. SFE was used to extract and successfully retain them. This enabled the first carbon isotopic analysis of this poorly understood material to be performed at the molecular level by GCIRMS. δ 13C values for aromatic pyrolysis products occupied a range from -24.6 to -5.6‰. The trend of 13C-enrichment with increasing carbon number, observed in the free compounds, was also evident in the macromolecular fragments. Furthermore, the organic fragments of the macromolecular material were consistently 13C-enriched when compared to structurally identical free molecules. This suggested that the free aromatic hydrocarbons in Murchison were produced by the preterrestrial degradation of the organic macromolecular material. This natural degradation event was extended by the hydrous pyrolysis experiment.

Procedures of determining organic trace compounds in municipal sewage sludge-a review.

PubMed

Lindholm-Lehto, Petra C; Ahkola, Heidi S J; Knuutinen, Juha S

2017-02-01

Sewage sludge is the largest by-product generated during the wastewater treatment process. Since large amounts of sludge are being produced, different ways of disposal have been introduced. One tempting option is to use it as fertilizer in agricultural fields due to its high contents of inorganic nutrients. This, however, can be limited by the amount of trace contaminants in the sewage sludge, containing a variety of microbiological pollutants and pathogens but also inorganic and organic contaminants. The bioavailability and the effects of trace contaminants on the microorganisms of soil are still largely unknown as well as their mixture effects. Therefore, there is a need to analyze the sludge to test its suitability before further use. In this article, a variety of sampling, pretreatment, extraction, and analysis methods have been reviewed. Additionally, different organic trace compounds often found in the sewage sludge and their methods of analysis have been compiled. In addition to traditional Soxhlet extraction, the most common extraction methods of organic contaminants in sludge include ultrasonic extraction (USE), supercritical fluid extraction (SFE), microwave-assisted extraction (MAE), and pressurized liquid extraction (PLE) followed by instrumental analysis based on gas or liquid chromatography and mass spectrometry.

Identification of Bioactivity, Volatile and Fatty Acid Profile in Supercritical Fluid Extracts of Mexican arnica.

PubMed

García-Pérez, J Saúl; Cuéllar-Bermúdez, Sara P; Arévalo-Gallegos, Alejandra; Rodríguez-Rodríguez, José; Iqbal, Hafiz M N; Parra-Saldivar, Roberto

2016-09-12

Supercritical fluid extraction (SFE) is a sustainable technique used for the extraction of lipophilic metabolites such as pigments and fatty acids. Arnica plant is considered a potential candidate material with high antioxidant and antimicrobial activities. Therefore, in this study, a locally available Heterotheca inuloides, also known as Mexican arnica, was analyzed for the extraction of high-value compounds. Based on different pressure (P), temperature (T), and co-solvent (CoS), four treatments (T) were prepared. A maximum 7.13% yield was recovered from T2 (T = 60 °C, P = 10 MPa, CoS = 8 g/min), followed by 6.69% from T4 (T = 60 °C, P = 30 MPa, CoS = 4 g/min). Some bioactive sesquiterpenoids such as 7-hydroxycadalene, caryophyllene and δ-cadinene were identified in the extracts by GC/MS. The fatty acid profile revealed that the main components were palmitic acid (C16:0), followed by linoleic acid (C18:2ω6c), α-linolenic acid (C18:3ω3) and stearic acid (C18:0) differing in percent yield per treatment. Antibacterial activities were determined by the agar diffusion method, indicating that all the treatments exerted strong antibacterial activity against S. aureus, C. albicans, and E. coli strains. The antioxidant capacity of the extracts was also measured by three in vitro assays, DPPH, TEAC and FRAP, using Trolox as a standard. Results showed high antioxidant capacity enabling pharmaceutical applications of Mexican arnica.

Identification of Bioactivity, Volatile and Fatty Acid Profile in Supercritical Fluid Extracts of Mexican arnica

PubMed Central

García-Pérez, J. Saúl; Cuéllar-Bermúdez, Sara P.; Arévalo-Gallegos, Alejandra; Rodríguez-Rodríguez, José; Iqbal, Hafiz M. N.; Parra-Saldivar, Roberto

2016-01-01

Supercritical fluid extraction (SFE) is a sustainable technique used for the extraction of lipophilic metabolites such as pigments and fatty acids. Arnica plant is considered a potential candidate material with high antioxidant and antimicrobial activities. Therefore, in this study, a locally available Heterotheca inuloides, also known as Mexican arnica, was analyzed for the extraction of high-value compounds. Based on different pressure (P), temperature (T), and co-solvent (CoS), four treatments (T) were prepared. A maximum 7.13% yield was recovered from T2 (T = 60 °C, P = 10 MPa, CoS = 8 g/min), followed by 6.69% from T4 (T = 60 °C, P = 30 MPa, CoS = 4 g/min). Some bioactive sesquiterpenoids such as 7-hydroxycadalene, caryophyllene and δ-cadinene were identified in the extracts by GC/MS. The fatty acid profile revealed that the main components were palmitic acid (C16:0), followed by linoleic acid (C18:2ω6c), α-linolenic acid (C18:3ω3) and stearic acid (C18:0) differing in percent yield per treatment. Antibacterial activities were determined by the agar diffusion method, indicating that all the treatments exerted strong antibacterial activity against S. aureus, C. albicans, and E. coli strains. The antioxidant capacity of the extracts was also measured by three in vitro assays, DPPH, TEAC and FRAP, using Trolox as a standard. Results showed high antioxidant capacity enabling pharmaceutical applications of Mexican arnica. PMID:27626416

Analysis of DDT and its metabolites in soil and water samples obtained in the vicinity of a closed-down factory in Bangladesh using various extraction methods.

PubMed

Al Mahmud, M N U; Khalil, Farzana; Rahman, Md Musfiqur; Mamun, M I R; Shoeb, Mohammad; Abd El-Aty, A M; Park, Jong-Hyouk; Shin, Ho-Chul; Nahar, Nilufar; Shim, Jae-Han

2015-12-01

This study was conducted to monitor the spread of dichlorodiphenyltrichloroethane (DDT) and its metabolites (dichlorodiphenyldichloroethylene (DDE), dichlorodiphenyldichloroethane (DDD)) in soil and water to regions surrounding a closed DDT factory in Bangladesh. This fulfillment was accomplished using inter-method and inter-laboratory validation studies. DDTs (DDT and its metabolites) from soil samples were extracted using microwave-assisted extraction (MAE), supercritical fluid extraction (SFE), and solvent extraction (SE). Inter-laboratory calibration was assessed by SE, and all methods were validated by intra- and inter-day accuracy (expressed as recovery %) and precision (expressed as relative standard deviation (RSD)) in the same laboratory, at three fortified concentrations (n = 4). DDTs extracted from water samples by liquid-liquid partitioning and all samples were analyzed by gas chromatography (GC)-electron capture detector (ECD) and confirmed by GC/mass spectrometry (GC/MS). Linearities expressed as determination coefficients (R (2)) were ≥0.995 for matrix-matched calibrations. The recovery rate was in the range of 72-120 and 83-110%, with <15% RSD in soil and water, respectively. The limit of quantification (LOQ) was 0.0165 mg kg(-1) in soil and 0.132 μg L(-1) in water. Greater quantities of DDTs were extracted from soil using the MAE and SE techniques than with the SFE method. Higher amounts of DDTs were discovered in the southern (2.2-936 × 10(2) mg kg(-1)) or southwestern (86.3-2067 × 10(2) mg kg(-1)) direction from the factory than in the eastern direction (1.0-48.6 × 10(2) mg kg(-1)). An exception was the soil sample collected 50 ft (15.24 m) east (2904 × 10(2) mg kg(-1)) of the factory. The spread of DDTs in the water bodies (0.59-3.01 μg L(-1)) was approximately equal in all directions. We concluded that DDTs might have been dumped randomly around the warehouse after the closing of the factory.

Application of reference-modified density functional theory: Temperature and pressure dependences of solvation free energy.

PubMed

Sumi, Tomonari; Maruyama, Yutaka; Mitsutake, Ayori; Mochizuki, Kenji; Koga, Kenichiro

2018-02-05

Recently, we proposed a reference-modified density functional theory (RMDFT) to calculate solvation free energy (SFE), in which a hard-sphere fluid was introduced as the reference system instead of an ideal molecular gas. Through the RMDFT, using an optimal diameter for the hard-sphere reference system, the values of the SFE calculated at room temperature and normal pressure were in good agreement with those for more than 500 small organic molecules in water as determined by experiments. In this study, we present an application of the RMDFT for calculating the temperature and pressure dependences of the SFE for solute molecules in water. We demonstrate that the RMDFT has high predictive ability for the temperature and pressure dependences of the SFE for small solute molecules in water when the optimal reference hard-sphere diameter determined for each thermodynamic condition is used. We also apply the RMDFT to investigate the temperature and pressure dependences of the thermodynamic stability of an artificial small protein, chignolin, and discuss the mechanism of high-temperature and high-pressure unfolding of the protein. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Separation and preparation of 6-gingerol from molecular distillation residue of Yunnan ginger rhizomes by high-speed counter-current chromatography and the antioxidant activity of ginger oils in vitro.

PubMed

Gan, Zhilin; Liang, Zheng; Chen, Xiaosong; Wen, Xin; Wang, Yuxiao; Li, Mo; Ni, Yuanying

2016-02-01

Molecular distillation residue (MD-R) from ginger had the most total phenol content of 247.6mg gallic acid equivalents per gram (GAE/g) among the ginger oils. High-speed counter-current chromatography (HSCCC) technique in semi-preparative scale was successfully performed in separation and purification of 6-gingerol from MD-R by using a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (10:2:5:7, v/v/v/v). The target compound was isolated, collected, purified by HSCCC in the head-tail mode, and then analyzed by HPLC. A total of 90.38±0.53mg 6-gingerol was obtained from 600mg MD-R, with purity of 99.6%. In addition, the structural identification of 6-gingerol was performed by EI/MS, (1)H NMR and (13)C NMR. Moreover, the orders of antioxidant activity were vitamin E (VE)>supercritical fluid extraction oleoresin (SFE-O)=MD-R=6-gingerol>molecular distillation essential oil (MD-EO) and butylated hydroxytoluene (BHT)=VE>6-gingerol>MD-R=SFE-O>MD-EO, respectively in 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging and β-Carotene bleaching. Copyright © 2016 Elsevier B.V. All rights reserved.

Influence of soil γ-irradiation and spiking on sorption of p,p'-DDE and soil organic matter chemistry.

PubMed

Škulcová, Lucia; Scherr, Kerstin E; Chrást, Lukáš; Hofman, Jakub; Bielská, Lucie

2018-07-15

The fate of organic chemicals and their metabolites in soils is often investigated in model matrices having undergone various pre-treatment steps that may qualitatively or quantitatively interfere with the results. Presently, effects associated with soil sterilization by γ-irradiation and soil spiking using an organic solvent were studied in one freshly spiked soil (sterilization prior to contamination) and its field-contaminated (sterilization after contamination) counterpart for the model organic compound 1,1-Dichloro-2,2-bis(4-chlorophenyl)ethene (p,p'-DDE). Changes in the sorption and potential bioavailability of spiked and native p,p'-DDE were measured by supercritical fluid extraction (SFE), XAD-assisted extraction (XAD), and solid-phase microextraction (SPME) and linked to qualitative changes in soil organic matter (SOM) chemistry measured by diffuse reflectance infrared Fourier-transform (DRIFT) spectroscopy. Reduced sorption of p,p´-DDE detected with XAD and SPME was associated more clearly with spiking than with sterilization, but SFE showed a negligible impact. Spiking resulted in an increase of the DRIFT-derived hydrophobicity index, but irradiation did not. Spectral peak height ratio descriptors indicated increasing hydrophobicity and hydrophilicity in pristine soil following sterilization, and a greater reduction of hydrophobic over hydrophilic groups as a consequence of spiking. In parallel, reduced sorption of p,p´-DDE upon spiking was observed. Based on the present samples, γ-irradiation appears to alter soil sorptive properties to a lesser extent when compared to common laboratory processes such as spiking with organic solvents. Copyright © 2018. Published by Elsevier Inc.

An Efficient Extraction Method for Fragrant Volatiles from Jasminum sambac (L.) Ait.

PubMed

Ye, Qiuping; Jin, Xinyi; Zhu, Xinliang; Lin, Tongxiang; Hao, Zhilong; Yang, Qian

2015-01-01

The sweet smell of aroma of Jasminum sambac (L.) Ait. is releasing while the flowers are blooming. Although components of volatile oil have been extensively studied, there are problematic issues, such as low efficiency of yield, flavour distortion. Here, the subcritical fluid extraction (SFE) was performed to extract fragrant volatiles from activated carbon that had absorbed the aroma of jasmine flowers. This novel method could effectively obtain main aromatic compounds with quality significantly better than solvent extraction (SE). Based on the analysis data with response surface methodology (RSM), we optimized the extraction conditions which consisted of a temperature of 44°C, a solvent-to-material ratio of 3.5:1, and an extraction time of 53 min. Under these conditions, the extraction yield was 4.91%. Furthermore, the key jasmine essence oil components, benzyl acetate and linalool, increase 7 fold and 2 fold respectively which lead to strong typical smell of the jasmine oil. The new method can reduce spicy components which lead to the essential oils smelling sweeter. Thus, the quality of the jasmine essence oil was dramatically improved and yields based on the key component increased dramatically. Our results provide a new effective technique for extracting fragrant volatiles from jasmine flowers.

The ultrasonic-enhanced factor of mass-transfer coefficient in the supercritical carbon dioxide extraction

NASA Astrophysics Data System (ADS)

Luo, Benyi; Lu, Yigang

2008-10-01

Based on several hypotheses about the process of supercritical carbon dioxide extraction, the onflow around the solute granule is figured out by the Navier-Stocks equation. In combination with the Higbie’s solute infiltration model, the link between the mass-transfer coefficient and the velocity of flow is found. The mass-transfer coefficient with the ultrasonical effect is compared with that without the ultrasonical effect, and then a new parameter named the ultrasonic-enhanced factor of mass-transfer coefficient is brought forward, which describes the mathematical model of the supercritical carbon dioxide extraction process enhanced by ultrasonic. The model gives out the relationships among the ultrasonical power, the ultrasonical frequency, the radius of solute granule and the ultrasonic-enhanced factor of mass-transfer coefficient. The results calculated by this model fit well with the experimental data, including the extraction of Coix Lacryma-jobi Seed Oil (CLSO) and Coix Lacryma-jobi Seed Ester (CLSE) from coix seeds and the extraction of Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) from the alga by means of the ultrasonic-enhanced supercritical carbon dioxide extraction (USFE) and the supercritical carbon dioxide extraction (SFE) respectively. This proves the rationality of the ultrasonic-enhanced factor model. The model provides a theoretical basis for the application of ultrasonic-enhanced supercritical fluid extraction technique.

Inhibitory Effects of Adlay Extract on Melanin Production and Cellular Oxygen Stress in B16F10 Melanoma Cells

PubMed Central

Huang, Huey-Chun; Hsieh, Wan-Yu; Niu, Yu-Lin; Chang, Tsong-Min

2014-01-01

The aim of this study was to determine the effects of adlay extract on melanin production and the antioxidant characteristics of the extract. The seeds were extracted by the supercritical fluid CO2 extraction (SFE) method. The effect of adlay extract on melanin production was evaluated using mushroom tyrosinase activity assay, intracellular tyrosinase activity, antioxidant properties and melanin content. Those assays were performed spectrophotometrically. In addition, the expression of melanogenesis-related proteins was determined by western blotting. The results revealed that the adlay extract suppressed intracellular tyrosinase activity and decreased the amount of melanin in B16F10 cells. The adlay extract decreased the expression of microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase related protein-1 (TRP-1) and tyrosinase related protein-2 (TRP-2). The extract also exhibited antioxidant characteristics such as free radical scavenging capacity and reducing power. It effectively decreased intracellular reactive oxygen species (ROS) levels in B16F10 cells. We concluded that the adlay extract inhibits melanin production by down-regulation of MITF, tyrosinase, TRP-1 and TRP-2. The antioxidant properties of the extract may also contribute to the inhibition of melanogenesis. The adlay extract can therefore be applied as an inhibitor of melanogenesis and could also act as a natural antioxidant in skin care products. PMID:25244016

Green Tea Leaves Extract: Microencapsulation, Physicochemical and Storage Stability Study.

PubMed

Zokti, James A; Sham Baharin, Badlishah; Mohammed, Abdulkarim Sabo; Abas, Faridah

2016-07-26

Green tea polyphenols have been reported to possess many biological properties. Despite the many potential benefits of green tea extracts, their sensitivity to high temperature, pH and oxygen is a major disadvantage hindering their effective utilization in the food industry. Green tea leaves from the Cameron Highlands Malaysia were extracted using supercritical fluid extraction (SFE). To improve the stability, green tea extracts were encapsulated by spray-drying using different carrier materials including maltodextrin (MD), gum arabic (GA) and chitosan (CTS) and their combinations at different ratios. Encapsulation efficiency, total phenolic content and antioxidant capacity were determined and were found to be in the range of 71.41%-88.04%, 19.32-24.90 (g GAE/100 g), and 29.52%-38.05% respectively. Further analysis of moisture content, water activity, hygroscopicity, bulk density and mean particles size distribution of the microparticles were carried out and the results ranged from; 2.31%-5.11%, 0.28-0.36, 3.22%-4.71%, 0.22-0.28 g/cm³ and 40.43-225.64 µm respectively. The ability of the microparticles to swell in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) was determined as 142.00%-188.63% and 207.55%-231.77%, respectively. Release of catechin polyphenol from microparticles in SIF was higher comparable to that of SGF. Storage stability of encapsulated catechin extracts under different temperature conditions was remarkably improved compared to non-encapsulated extract powder. This study showed that total catechin, total phenolic content (TPC) and antioxidant activity did not decrease significantly (p ≥ 0.05) under 4 °C storage conditions. The half-life study results were in the range of 35-60, 34-65 and 231-288 weeks at storage temperatures of 40 °C, 25 °C and 4 °C respectively, therefore, for improved shelf-life stability we recommend that microparticles should be stored at temperatures below 25 °C.

Identification and quantification of cannabinoids in Cannabis sativa L. plants by high performance liquid chromatography-mass spectrometry.

PubMed

Aizpurua-Olaizola, Oier; Omar, Jone; Navarro, Patricia; Olivares, Maitane; Etxebarria, Nestor; Usobiaga, Aresatz

2014-11-01

High performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) has been successfully applied to cannabis plant extracts in order to identify cannabinoid compounds after their quantitative isolation by means of supercritical fluid extraction (SFE). MS conditions were optimized by means of a central composite design (CCD) approach, and the analysis method was fully validated. Six major cannabinoids [tetrahydrocannabinolic acid (THCA), tetrahydrocannabinol (THC), cannabidiol (CBD), tetrahydrocannabivarin (THCV), cannabigerol (CBG), and cannabinol (CBN)] were quantified (RSD < 10%), and seven more cannabinoids were identified and verified by means of a liquid chromatograph coupled to a quadrupole-time-of-flight (Q-ToF) detector. Finally, based on the distribution of the analyzed cannabinoids in 30 Cannabis sativa L. plant varieties and the principal component analysis (PCA) of the resulting data, a clear difference was observed between outdoor and indoor grown plants, which was attributed to a higher concentration of THC, CBN, and CBD in outdoor grown plants.

Supercritical Fluid Spray Application Process for Adhesives and Primers

DTIC Science & Technology

2003-03-01

The basic scheme of SFE process consists of three steps. A solvent, typically carbon dioxide, first is heated and pressurized to a supercritical...passivation step to remove contaminants and to prevent recontamination. Bok et al. (25) describe a pressure pulsation mechanism to stimulate improved...in as a liquid, and then it is heated to above its critical temperature to become a supercritical fluid. The sample is injected and dissolved into

Development of green extraction processes for Nannochloropsis gaditana biomass valorization.

PubMed

Sánchez-Camargo, Andrea Del Pilar; Pleite, Natalia; Mendiola, José Antonio; Cifuentes, Alejandro; Herrero, Miguel; Gilbert-López, Bienvenida; Ibáñez, Elena

2018-04-23

In the present work, the valorization of Nannochloropsis gaditana biomass is proposed within the concept of biorefinery. To this aim, high-pressure homogenization (HPH) was used to break down the strong cell wall and supercritical fluid extraction (SFE) with pure CO 2 was applied as a first step to extract valuable compounds (such as non-polar lipids and pigments). Extraction of the remaining residue for the recovery of bioactive compounds was studied by means of an experimental design based on response surface methodology (RSM) employing pressurized liquid extraction (PLE) with green solvents such as water and ethanol. Optimum extract was achieved with pure ethanol at 170°C for 20 min, providing an important antioxidant capacity (0.72 ± 0.03 mmol trolox eq g -1 extract). Complete chemical characterization of the optimum extract was carried out by using different chromatographic methods such as reverse-phase high-performance liquid chromatography with diode array detection (RP-HPLC-DAD), normal-phase HPLC with evaporative light scattering detection (NP-HPLC-ELSD) and gas chromatography coupled to mass spectrometry detection (GC-MS); carotenoids (e.g. violaxanthin), chlorophylls and polar lipids were the main compounds observed while palmitoleic, palmitic, myristic acids and the polyunsaturated eicosapentanoic (EPA) acid were the predominant fatty acids in all PLE extracts. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Determination of the volatile and semi-volatile secondary metabolites, and aristolochic acids in Aristolochia ringens Vahl.

PubMed

Stashenko, Elena E; Andrés Ordóñez, Sergio; Marín, Néstor Armando; Martínez, Jairo René

2009-10-01

Volatile and semi-volatile secondary metabolites, as well as aristolochic acids (AA), present in leaves, stems, and flowers of Aristolochia ringens were determined by gas chromatography (GC)-mass spectrometry (MS) and high-performance liquid chromatography (HPLC) methods, respectively. Metabolite isolation was performed using different extraction techniques: microwave-assisted hydrodistillation (MWHD), supercritical fluid extraction, and headspace solid-phase microextraction (HS-SPME). The chemical composition of the extracts and oils was established by GC-MS. The determinations of AAI and AAII were conducted by methanolic extraction of different plant parts followed by HPLC analysis. Essential oil yields from leaves and stems were 0.008 +/- 0.0022% and 0.047 +/- 0.0026%, respectively. Aristolochia ringens flowers did not yield essential oil under MWHD. Sesquiterpene hydrocarbons (66%) were the main compounds in the essential oil isolated from leaves whereas monoterpene hydrocarbons (73%) predominated in the stems essential oil. Yields of extracts isolated by SFE from leaves, stems, and flowers were 4 +/- 1.8%, 1.2 +/- 0.25%, and 4 +/- 1.8%, respectively. In vivo HS-SPME of flowers isolated compounds with known unpleasant smells such as volatile aldehydes and short-chain carboxylic acids. HPLC analysis detected the presence of AAII in the flowers of Aristolochia ringens at a concentration of 610 +/- 47 mg/kg of dried flower.

Steroid hormones in environmental matrices: extraction method comparison.

PubMed

Andaluri, Gangadhar; Suri, Rominder P S; Graham, Kendon

2017-11-09

The U.S. Environmental Protection Agency (EPA) has developed methods for the analysis of steroid hormones in water, soil, sediment, and municipal biosolids by HRGC/HRMS (EPA Method 1698). Following the guidelines provided in US-EPA Method 1698, the extraction methods were validated with reagent water and applied to municipal wastewater, surface water, and municipal biosolids using GC/MS/MS for the analysis of nine most commonly detected steroid hormones. This is the first reported comparison of the separatory funnel extraction (SFE), continuous liquid-liquid extraction (CLLE), and Soxhlet extraction methods developed by the U.S. EPA. Furthermore, a solid phase extraction (SPE) method was also developed in-house for the extraction of steroid hormones from aquatic environmental samples. This study provides valuable information regarding the robustness of the different extraction methods. Statistical analysis of the data showed that SPE-based methods provided better recovery efficiencies and lower variability of the steroid hormones followed by SFE. The analytical methods developed in-house for extraction of biosolids showed a wide recovery range; however, the variability was low (≤ 7% RSD). Soxhlet extraction and CLLE are lengthy procedures and have been shown to provide highly variably recovery efficiencies. The results of this study are guidance for better sample preparation strategies in analytical methods for steroid hormone analysis, and SPE adds to the choice in environmental sample analysis.

Accelerator mass spectrometry analysis of aroma compound absorption in plastic packaging materials

NASA Astrophysics Data System (ADS)

Stenström, Kristina; Erlandsson, Bengt; Hellborg, Ragnar; Wiebert, Anders; Skog, Göran; Nielsen, Tim

1994-05-01

Absorption of aroma compounds in plastic packaging materials may affect the taste of the packaged food and it may also change the quality of the packaging material. A method to determine the aroma compound absorption in polymers by accelerator mass spectrometry (AMS) is being developed at the Lund Pelletron AMS facility. The high sensitivity of the AMS method makes it possible to study these phenomena under realistic conditions. As a first test low density polyethylene exposed to 14C-doped ethyl acetate is examined. After converting the polymer samples with the absorbed aroma compounds to graphite, the {14C }/{13C } ratio of the samples is measured by the AMS system and the degree of aroma compound absorption is established. The results are compared with those obtained by supercritical fluid extraction coupled to gas chromatography (SFE-GC).

Anti-inflammatory and antiallergic activity in vivo of lipophilic Isatis tinctoria extracts and tryptanthrin.

PubMed

Recio, María-Carmen; Cerdá-Nicolás, Miguel; Potterat, Olivier; Hamburger, Matthias; Ríos, José-Luis

2006-05-01

The effects of a supercritical CO2 (SFE) extract, a dichloromethane (DCM) extract from Isatis tinctoria leaf and the alkaloidal constituent tryptanthrin were studied in acute and subchronic experimental models of inflammation. The SFE and DCM extracts showed anti-inflammatory activity in the carrageenan-induced acute mouse paw oedema (ED50 values of 78 mg/kg and 165 mg/kg P. O., respectively) and in the acute tetradecanoylphorbol acetate (TPA)-induced mouse ear oedema in oral (62% and 32% oedema reduction at 100 and 125 mg/kg, respectively) and topical application (37% and 33% reduction of oedema at 0.5 mg/ear). In contrast, tryptanthrin showed no significant anti-inflammatory effect. The DCM extract inhibited oedema formation and neutrophil infiltration in subchronic inflammation in mice induced by repeated application of TPA. The extract showed activity after oral and topical administration by reducing the various parameters of the inflammatory response. The DCM extract (1 mg/ear) inhibited the delayed-type hypersensitivity (DTH) reaction induced by application of dinitrofluorobenzene (DNFB) after topical application. The response during the induction phase (24 h) was decreased by 48%, and the inflammatory phase (48 to 96 h) was reduced by 53 to 56%. The extract had no effect in this model when administered orally. The DCM extract (200 mg/kg P. O.) inhibited the acetic acid-induced writhing by 49%.

LIQUID-SOLID DISK EXTRACTION FOLLOWED BY SFE AND GC-ION-TRAP MS FOR THE DETERMINATION OF TRACE ORGANIC POLLUTANTS IN WATER

EPA Science Inventory

The U.S. Environmental Protection Agency's (EPA) Industrial Toxic 33-50 Program, which is part of the Pollution Prevention Act of 1990, outlines a plan to reduce the use of some commonly used liquid solvents. One of the most widely used solvents for extraction of organic contamin...

Supercritical carbon dioxide extract exhibits enhanced antioxidant and anti-inflammatory activities of Physalis peruviana.

PubMed

Wu, S J; Tsai, J Y; Chang, S P; Lin, D L; Wang, S S; Huang, S N; Ng, L T

2006-12-06

Physalis peruviana L. (PP) is a medicinal herb widely used in folk medicine. In this study, supercritical carbon dioxide (SFE-CO2) method was employed to obtain three different PP extracts, namely SCEPP-0, SCEPP-4 and SCEPP-5. The total flavonoid and phenol concentrations, as well as antioxidant and anti-inflammatory activities of these extracts were analyzed and compared with aqueous and ethanolic PP extracts. Among all the extracts tested, SCEPP-5 demonstrated the highest total flavonoid (234.63+/-9.61 mg/g) and phenol (90.80+/-2.21 mg/g) contents. At concentrations 0.1-30 microg/ml, SCEPP-5 also demonstrated the strongest superoxide anion scavenging activity and xanthine oxidase inhibitory effect. At 30 microg/ml, SCEPP-5 significantly prevented lipopolysaccharide (LPS; 1 microg/ml)-induced cell cytotoxicity in murine macrophage (Raw 264.7) cells. At 10-50 microg/ml, it also significantly inhibited LPS-induced NO release and PGE2 formation in a dose-dependent pattern. SCEPP-5 at 30 microg/ml remarkably blocked the LPS induction of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression. Taken together, these results suggest that SCEPP-5, an extract of SFE-CO2, displayed the strongest antioxidant and anti-inflammatory activities as compared to other extracts. Its protection against LPS-induced inflammation could be through the inhibition of iNOS and COX-2 expression.

Sediment certified reference materials for the determination of polychlorinated biphenyls and organochlorine pesticides from the National Metrology Institute of Japan (NMIJ).

PubMed

Numata, Masahiko; Yarita, Takashi; Aoyagi, Yoshie; Tsuda, Yoko; Yamazaki, Misako; Takatsu, Akiko; Ishikawa, Keiichiro; Chiba, Koichi; Okamaoto, Kensaku

2007-04-01

Two marine sediment certified reference materials, NMIJ CRM 7304-a and 7305-a, have been issued by the National Metrology Institute of Japan in the National Institute of Advanced Industrial Science and Technology (NMIJ/AIST) for the determination of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs). The raw materials of the CRMs were collected from a bay near industrial activity in Japan. Characterization of these CRMs was conducted by NMIJ, where the sediments were analyzed using multiple analytical methods such as pressurized liquid extraction (PLE), microwave-assisted extraction (MAE), saponification, Soxhlet extraction, supercritical fluid extraction (SFE), and ultrasonic extraction; the target compounds were determined by one of the primary methods of measurements, isotope dilution-mass spectrometry (ID-MS). Certified values have been provided for 14 PCB congeners (PCB numbers 3, 15, 28, 31, 70, 101, 105, 138, 153, 170, 180, 194, 206, 209) and 4 OCPs (gamma-HCH, 4,4'-DDT, 4,4'-DDE, 4,4'-DDD) in both CRMs. NMIJ CRM 7304-a has concentrations of the contaminants that are a factor of 2-15 greater than in CRM 7305-a. Both CRMs have information values for PCB homolog concentrations determined by collaborative analysis using a Japanese official method for determination of PCBs. The total PCB concentrations in the CRMs are approximately 920 and 86 microg kg(-1) dry mass respectively.

Effect of Supercritical Carbon Dioxide Extraction Parameters on the Biological Activities and Metabolites Present in Extracts from Arthrospira platensis.

PubMed

Esquivel-Hernández, Diego A; Rodríguez-Rodríguez, José; Cuéllar-Bermúdez, Sara P; García-Pérez, J Saúl; Mancera-Andrade, Elena I; Núñez-Echevarría, Jade E; Ontiveros-Valencia, Aura; Rostro-Alanis, Magdalena; García-García, Rebeca M; Torres, J Antonio; Chen, Wei Ning; Parra-Saldívar, Roberto

2017-06-12

Arthrospira platensis was used to obtain functional extracts through supercritical carbon dioxide extraction (SFE-CO₂). Pressure (P), temperature (T), co-solvent (CX), static extraction (SX), dispersant (Di) and dynamic extraction (DX) were evaluated as process parameters through a Plackett-Burman design. The maximum extract yield obtained was 7.48 ± 0.15% w/w. The maximum contents of bioactive metabolites in extracts were 0.69 ± 0.09 µg/g of riboflavin, 5.49 ± 0.10 µg/g of α-tocopherol, 524.46 ± 0.10 µg/g of β-carotene, 1.44 ± 0.10 µg/g of lutein and 32.11 ± 0.12 mg/g of fatty acids with 39.38% of palmitic acid, 20.63% of linoleic acid and 30.27% of γ-linolenic acid. A. platensis extracts had an antioxidant activity of 76.47 ± 0.71 µg GAE/g by Folin-Ciocalteu assay, 0.52 ± 0.02, 0.40 ± 0.01 and 1.47 ± 0.02 µmol TE/g by DPPH, FRAP and TEAC assays, respectively. These extracts showed antimicrobial activity against Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922 and Candida albicans ATCC 10231. Overall, co-solvent was the most significant factor for all measured effects ( p < 0.05). Arthrospira platensis represents a sustainable source of bioactive compounds through SFE using the following extraction parameters P: 450 bar, CX: 11 g/min, SX: 15 min, DX: 25 min, T: 60 °C and Di: 35 g.

Effect of Supercritical Carbon Dioxide Extraction Parameters on the Biological Activities and Metabolites Present in Extracts from Arthrospira platensis

PubMed Central

Esquivel-Hernández, Diego A.; Rodríguez-Rodríguez, José; Cuéllar-Bermúdez, Sara P.; García-Pérez, J. Saúl; Mancera-Andrade, Elena I.; Núñez-Echevarría, Jade E.; Ontiveros-Valencia, Aura; Rostro-Alanis, Magdalena; García-García, Rebeca M.; Torres, J. Antonio; Chen, Wei Ning; Parra-Saldívar, Roberto

2017-01-01

Arthrospira platensis was used to obtain functional extracts through supercritical carbon dioxide extraction (SFE-CO2). Pressure (P), temperature (T), co-solvent (CX), static extraction (SX), dispersant (Di) and dynamic extraction (DX) were evaluated as process parameters through a Plackett–Burman design. The maximum extract yield obtained was 7.48 ± 0.15% w/w. The maximum contents of bioactive metabolites in extracts were 0.69 ± 0.09 µg/g of riboflavin, 5.49 ± 0.10 µg/g of α-tocopherol, 524.46 ± 0.10 µg/g of β-carotene, 1.44 ± 0.10 µg/g of lutein and 32.11 ± 0.12 mg/g of fatty acids with 39.38% of palmitic acid, 20.63% of linoleic acid and 30.27% of γ-linolenic acid. A. platensis extracts had an antioxidant activity of 76.47 ± 0.71 µg GAE/g by Folin–Ciocalteu assay, 0.52 ± 0.02, 0.40 ± 0.01 and 1.47 ± 0.02 µmol TE/g by DPPH, FRAP and TEAC assays, respectively. These extracts showed antimicrobial activity against Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922 and Candida albicans ATCC 10231. Overall, co-solvent was the most significant factor for all measured effects (p < 0.05). Arthrospira platensis represents a sustainable source of bioactive compounds through SFE using the following extraction parameters P: 450 bar, CX: 11 g/min, SX: 15 min, DX: 25 min, T: 60 °C and Di: 35 g. PMID:28604646

Supercritical Fluid Extraction of Biogenic SOA in Northern Michigan

NASA Astrophysics Data System (ADS)

Flores, R. M.; Doskey, P. V.; Perlinger, J. A.

2010-12-01

Secondary organic aerosols (SOA) are formed by photooxidation of volatile organic compounds (VOCs) and nucleation and condensation of the oxygenated products. On a global scale, monoaromatic hydrocarbons of anthropogenic origin are estimated to be the source of 12% of the SOA while biogenic emissions of isoprene (C5H8), monoterpenes (C10H16), and sesquiterpenes (C15H24) are estimated to be the source of 46, 29 and 7% of SOA, respectively. The functional groups of organic substances comprising SOA (i.e., hydroxyl, carbonyl, carboxylic acid, sulfate, and nitrate) complicate sample processing, analysis, and identification of the characteristic aerosol products of VOC oxidation pathways. Only a very small fraction of the organic molecular species in SOA have been identified due to the complexity of precursor oxidation reactions and the need for (1) methodologies that are less labor intensive and suitable for thermally labile compounds and (2) analytic instrumentation that provides more complete resolution of complex mixtures for sensitive detection of molecular species. Extraction techniques commonly used include solvent extraction, which requires large amounts of solvent and is labor intensive and thermal desorption, which evolves organic substances from aerosol at temperatures not suitable for thermally labile compounds. A promising technique that does not involve sample processing with solvents or high temperatures is supercritical fluid extraction (SFE). In this work, the composition of biogenic SOA was studied in Northern Michigan. Aerosol samples were collected on quartz fiber filters with a high-volume air sampler and extracted with supercritical CO2. Carboxylic and hydroxyl compounds were derivatized during static extraction conditions and identified by comprehensive two dimensional gas chromatography with time-of-flight mass spectrometric detection (GC×GC-TOFMS). The overall goal of the research is to couple the post-collection analytic scheme developed here with a rapid sampling technique to evaluate SOA produced from a variety of biogenic and anthropogenic sources of precursors in the Midwestern United States.

COMPARISON OF FIVE EXTRACTION METHODS ON INCURRED AND FORTIFIED PESTICIDES IN COMPOSITE DIETS: BLENDER, SOXHLET, ASE, MICROWAVE AND SFE

EPA Science Inventory

The USEPA National Exposure Research Laboratory studies dietary exposure to a diverse group of semi-volatile pesticides by analyzing 24 hour duplicate composite diets. The pesticides of interest include organochlorines, organophosphates, anilines, and triazines. Currently, there ...

Remediation of Contaminated Soils By Supercritical Carbon Dioxide Extraction

NASA Astrophysics Data System (ADS)

Ferri, A.; Zanetti, M. C.; Banchero, M.; Fiore, S.; Manna, L.

The contaminants that can be found in soils are many, inorganic, like heavy metals, as well as organic. Among the organic contaminants, oil and coal refineries are responsi- ble for several cases of soil contamination with PAHs (Polycyclic Aromatic Hydrocar- bons). Polynuclear aromatic hydrocarbons (PAHs) have toxic, carcinogenic and mu- tagenic effects. Limits have been set on the concentration of most contaminants, and growing concern is focusing on soil contamination issues. USA regulations set the maximum acceptable level of contamination by PAHs equal to 40 ppm at residential sites and 270 ppm at industrial sites. Stricter values are usually adopted in European Countries. Supercritical carbon dioxide extraction is a possible alternative technology to remove volatile organic compounds from contaminated soils. Supercritical fluid extraction (SFE) offers many advantages over conventional solvent extraction. Super- critical fluids combine gaseous properties as a high diffusion coefficient, and liquid properties as a high solvent power. The solvent power is strongly pressure-dependent near supercritical conditions: selective extractions are possible without changing the solvent. Solute can be separate from the solvent depressurising the system; therefore, it is possible to recycle the solvent and recover the contaminant. Carbon dioxide is frequently used as supercritical fluid, because it has moderate critical conditions, it is inert and available in pure form. In this work, supercritical fluid extraction technology has been used to remove a polynuclear aromatic hydrocarbon from contaminated soils. The contaminant choice for the experiment has been naphthalene since several data are available in literature. G. A. Montero et al. [1] studied soil remediation with supercrit- ical carbon dioxide extraction technology; these Authors have found that there was a mass-transfer limitation. In the extraction vessel, the mass transfer coefficient in- creases with the superficial velocity of the supercritical carbon dioxide; therefore, the mass transfer resistance can be reduced increasing such velocity. In this work, higher values of superficial velocity were investigated. The experimental apparatus includes a pump, an extraction vessel, an adjustable restrictor and a trap to collect the extracted substance. Liquid carbon dioxide coming from a cylinder with a dip-tube is cooled by a cryostatic bath and then it is compressed by a pneumatic drive pump (the max- imum available pressure is 69 MPa). Subsequently, the pressurised current flows into 1 a heating coil and then into the extraction vessel, which is contained in a stove; the outlet flow is depressurised in an adjustable restrictor and the extracted substance is collected in a trap by dissolution into a solvent. The extracted naphthalene quantity was obtained by weighting the solvent and measuring the naphthalene concentration with a gas chromatograph. The soil sample is a sandy soil geologically representative of the North of Italy that was sampled and physically and chemically characterized: particle-size distribution analysis, diffractometric analysis, Cation Exchange Capac- ity, Total Organic Carbon, iron content and manganese content in order to evaluate the potential sorption degree. The soil was artificially polluted by means of a naphta- lene and methylene chloride solution. The experimental work consists in a number of naphthalene extractions from the spiked soil, that were carried out at different operat- ing conditions, temperature, pressure and flow rate by means of supercritical carbon dioxide evaluating the corresponding recovery efficiencies. The results obtained were analysed and compared in order to determine which parameters influence the system. [1] G. A. Montero, T.D. Giorgio, and K. B. Schnelle, Jr..Removal of Hazardous ,1994, Contaminants form Soils by Supercritical Fluid Extraction. Innovations in Supercriti- cal Fluids. ACS Symposium Series, 608, 280-197. 2

JV Task 92 - Alcoa/Retec SFE and SPME

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steven Hawthorne

2009-02-15

This report summarizes the work performed by the Energy & Environmental Research Center (EERC) under the U.S. Department of Energy Jointly Sponsored Research Program JV Task 92, which is a continuation of JV9. Successful studies performed in 1999 through the end of 2008 demonstrated the potential for using selective supercritical fluid extraction (SFE) and a solid-phase microextraction (SPME) method for measuring sediment pore water polycyclic aromatic hydrocarbons (PAHs) to mimic the bioavailability of PAHs from manufactured gas plant and aluminum smelter soils and sediments both in freshwater and saltwater locations. The studies that the EERC has performed with the commercialmore » partners have continued to generate increased interest in both the regulatory communities and in the industries that have historically produced or utilized coal tar products. Both ASTM International and the U.S. Environmental Protection Agency (EPA) have accepted the pore water method developed at the EERC as standard methods. The studies have demonstrated the effectiveness of our techniques in predicting bioavailability of PAHs from ca. 250 impacted and background field sediments and soils. The field demonstrations from the final years of the project continued to build the foundation data for acceptance of our methods by the regulatory communities. The JV92 studies provide the single largest database in the world that includes measures of PAH bioavailability along with biological end points. These studies clearly demonstrated that present regulatory paradigms based on equilibrium partitioning greatly overpredict bioavailability. These investigations also laid the foundation for present (non-JV) studies being applied to PAHs and polychlorinated biphenyls (PCBs) at EPA Superfund sites, investigations into PAH and PCB bioavailability at U.S Department of Defense sites, and the application of the techniques to investigating the bioavailability of chlorinated dioxins and furans from impacted sediments.« less

Gamma-oryzanol rich fraction regulates the expression of antioxidant and oxidative stress related genes in stressed rat's liver.

PubMed

Ismail, Maznah; Al-Naqeeb, Ghanya; Mamat, Wan Abd Aziz Bin; Ahmad, Zalinah

2010-03-24

Gamma-oryzanol (OR), a phytosteryl ferulate mixture extracted from rice bran oil, has a wide spectrum of biological activities in particular, it has antioxidant properties. The regulatory effect of gamma-oryzanol rich fraction (ORF) extracted and fractionated from rice bran using supercritical fluid extraction (SFE) in comparison with commercially available OR on 14 antioxidant and oxidative stress related genes was determined in rat liver. Rats were subjected to a swimming exercise program for 10 weeks to induce stress and were further treated with either ORF at 125, 250 and 500 mg/kg or OR at 100 mg/kg in emulsion forms for the last 5 weeks of the swimming program being carried out. The GenomeLab Genetic Analysis System (GeXPS) was used to study the multiplex gene expression of the selected genes. Upon comparison of RNA expression levels between the stressed and untreated group (PC) and the unstressed and untreated group (NC), seven genes were found to be down-regulated, while seven genes were up-regulated in PC group compared to NC group. Further treatment of stressed rats with ORF at different doses and OR resulted in up-regulation of 10 genes and down regulation of four genes compared to the PC group. Gamma-oryzanol rich fraction showed potential antioxidant activity greater than OR in the regulation of antioxidants and oxidative stress gene markers.

Analytical methods for determination of mycotoxins: a review.

PubMed

Turner, Nicholas W; Subrahmanyam, Sreenath; Piletsky, Sergey A

2009-01-26

Mycotoxins are small (MW approximately 700), toxic chemical products formed as secondary metabolites by a few fungal species that readily colonise crops and contaminate them with toxins in the field or after harvest. Ochratoxins and Aflatoxins are mycotoxins of major significance and hence there has been significant research on broad range of analytical and detection techniques that could be useful and practical. Due to the variety of structures of these toxins, it is impossible to use one standard technique for analysis and/or detection. Practical requirements for high-sensitivity analysis and the need for a specialist laboratory setting create challenges for routine analysis. Several existing analytical techniques, which offer flexible and broad-based methods of analysis and in some cases detection, have been discussed in this manuscript. There are a number of methods used, of which many are lab-based, but to our knowledge there seems to be no single technique that stands out above the rest, although analytical liquid chromatography, commonly linked with mass spectroscopy is likely to be popular. This review manuscript discusses (a) sample pre-treatment methods such as liquid-liquid extraction (LLE), supercritical fluid extraction (SFE), solid phase extraction (SPE), (b) separation methods such as (TLC), high performance liquid chromatography (HPLC), gas chromatography (GC), and capillary electrophoresis (CE) and (c) others such as ELISA. Further currents trends, advantages and disadvantages and future prospects of these methods have been discussed.

DETERMINATION OF CHLORDANE IN SOIL BY LC/GC/ECD AND LC/GC/EC NIMS WITH COMPARISON OF ASE, SFE, AND SOXHLET EXTRACTION

EPA Science Inventory

Chlordane is a polychlorinated mixture that was used as a long-lived pesticide and now is considered a potential endocrine-disrupting compound. The Environmental Sciences Division is involved in modernizing methods for a number of analytes that are potential target substances for...

Comparing PAH availability from manufactured gas plant soils and sediments with chemical and biological tests. 1. PAH release during water desorption and supercritical carbon dioxide extraction.

PubMed

Hawthorne, Steven B; Poppendieck, Dustin G; Grabanski, Carol B; Loehr, Raymond C

2002-11-15

Soil and sediment samples from oil gas (OG) and coal gas (CG) manufactured gas plant (MGP) sites were selected to represent a range of PAH concentrations (150-40,000 mg/kg) and sample matrix compositions. Samples varied from vegetated soils to lampblack soot and had carbon contents from 3 to 87 wt %. SFE desorption (120 min) and water/XAD2 desorption (120 days) curves were determined and fit with a simple two-site model to determine the rapid-released fraction (F) for PAHs ranging from naphthalene to benzo[ghi]perylene. F values varied greatly among the samples, from ca. 10% to >90% for the two- and three-ring PAHs and from <1% to ca. 50% for the five- and six-ring PAHs. Release rates did not correlate with sample matrix characteristics including PAH concentrations, elemental composition (C, H, N, S), or "hard" and "softs" organic carbon, indicating that PAH release cannot easily be estimated on the basis of sample matrix composition. Fvalues for CG site samples obtained with SFE and water desorption agreed well (linear correlation coefficient, r2 = 0.87, slope = 0.93), but SFE yielded higher F values for the OG samples. These behaviors were attributed to the stronger ability of carbon dioxide than water to desorb PAHs from the highly aromatic (hard) carbon of the OG matrixes, while carbon dioxide and water showed similar abilities to desorb PAHs from the more polar (soft) carbon of the CG samples. The combined SFE and water desorption approaches should improve the understanding of PAH sequestration and release from contaminated soils and sediments and provide the basis for subsequent studies using the same samples to compare PAH release with PAH availability to earthworms.

[Optimization for supercritical CO2 extraction with response surface methodology of Prunus armeniaca oil].

PubMed

Chen, Fei-Fei; Wu, Yan; Ge, Fa-Huan

2012-03-01

To optimize the extraction conditions of Prunus armeniaca oil by Supercritical CO2 extraction and identify its components by GC-MS. Optimized of SFE-CO extraction by response surface methodology and used GC-MS to analysis Prunus armeniaca oil compounds. Established the model of an equation for the extraction rate of Prunus armeniaca oil by supercritical CO2 extraction, and the optimal parameters for the supercritical CO2 extraction determined by the equation were: the extraction pressure was 27 MPa, temperature was 39 degrees C, the extraction rate of Prunus armeniaca oil was 44.5%. 16 main compounds of Prunus armeniaca oil extracted by supercritical CO2 were identified by GC-MS, unsaturated fatty acids were 92.6%. This process is simple, and can be used for the extraction of Prunus armeniaca oil.

[Gas chromatography for analysis of essential oils. Characteristics of essential oil of Dracocephalum species and the influence of extraction method on its composition].

PubMed

Lemberkovics, Eva; Kakasy, András Zoltán; Héthelyi, B Eva; Simándi, Béla; Böszörményi, Andrea; Balázs, Andrea; Szoke, Eva

2007-01-01

In this work the essential oil composition of some less known Dracocephalum species was studied and compared the effectiveness, selectivity and influence of different extraction methods (hydrodistillation, Soxhlet extraction with organic solvents and supercritical fluid extraction) on essential oils. For investigations in Hungary and Transylvania cultivated plant material was used. The analysis of essential oils was carried out by GC and GC-MS methods. The components were identified by standard addition, retention factors and mass spectra. The percentile evaluation of each volatile constituents was made on basis of GC-FID chromatograms. The accuracy of measurements was characterized by relative standard deviation. In the essential oil of D. renati Emb. (studied firstly by us) 18.3% of limonene was measured and carvone, citrals and linalyl acetate monoterpenes, methyl chavicol and some sesquiterpene (e.g. bicyclovetivenol) determined in lower quantities. We established that more than 50% of essential oil of D. grandiflorum L. was formed by sesquiterpenes (beta-caryophyllene and- oxide, beta-bourbonene, beta-cubebene, aromadendrene) and the essential oil of D. ruyschiana L. contained pinocamphone isomers in more than 60%. The oxygenated acyclic monoterpenes, the characteristic constituents of Moldavian dragonhead were present in some tenth percent only in D. renati oil. We found significant differences in the composition of the SFE extract and traditional essential oil of D. moldavica L. The supercritical fractions collected at the beginning of the extraction process were richer in valuable ester component (geranyl acetate) than the essential oil obtained by hydrodistillation. The fractions collected at the end of supercritical were poor in oxygenated monoterpenes but rich in minor compounds of traditional oil, e.g. palmitic acid.

Study on preparation method of Zanthoxylum bungeanum seeds kernel oil with zero trans-fatty acids.

PubMed

Liu, Tong; Yao, Shi-Yong; Yin, Zhong-Yi; Zheng, Xu-Xu; Shen, Yu

2016-04-01

The seed of Zanthoxylum bungeanum (Z. bungeanum) is a by-product of pepper production and rich in unsaturated fatty acid, cellulose, and protein. The seed oil obtained from traditional producing process by squeezing or extracting would be bad quality and could not be used as edible oil. In this paper, a new preparation method of Z. bungeanum seed kernel oil (ZSKO) was developed by comparing the advantages and disadvantages of alkali saponification-cold squeezing, alkali saponification-solvent extraction, and alkali saponification-supercritical fluid extraction with carbon dioxide (SFE-CO2). The results showed that the alkali saponification-cold squeezing could be the optimal preparation method of ZSKO, which contained the following steps: Z. bungeanum seed was pretreated by alkali saponification under the conditions of adding 10 %NaOH (w/w), solution temperature was 80 °C, and saponification reaction time was 45 min, and pretreated seed was separated by filtering, water washing, and overnight drying at 50 °C, then repeated squeezing was taken until no oil generated at 60 °C with 15 % moisture content, and ZSKO was attained finally using centrifuge. The produced ZSKO contained more than 90 % unsaturated fatty acids and no trans-fatty acids and be testified as a good edible oil with low-value level of acid and peroxide. It was demonstrated that the alkali saponification-cold squeezing process could be scaled up and applied to industrialized production of ZSKO.

Gamma-oryzanol rich fraction regulates the expression of antioxidant and oxidative stress related genes in stressed rat's liver

PubMed Central

2010-01-01

Background Gamma-oryzanol (OR), a phytosteryl ferulate mixture extracted from rice bran oil, has a wide spectrum of biological activities in particular, it has antioxidant properties. Methods The regulatory effect of gamma-oryzanol rich fraction (ORF) extracted and fractionated from rice bran using supercritical fluid extraction (SFE) in comparison with commercially available OR on 14 antioxidant and oxidative stress related genes was determined in rat liver. Rats were subjected to a swimming exercise program for 10 weeks to induce stress and were further treated with either ORF at 125, 250 and 500 mg/kg or OR at 100 mg/kg in emulsion forms for the last 5 weeks of the swimming program being carried out. The GenomeLab Genetic Analysis System (GeXPS) was used to study the multiplex gene expression of the selected genes. Results Upon comparison of RNA expression levels between the stressed and untreated group (PC) and the unstressed and untreated group (NC), seven genes were found to be down-regulated, while seven genes were up-regulated in PC group compared to NC group. Further treatment of stressed rats with ORF at different doses and OR resulted in up-regulation of 10 genes and down regulation of four genes compared to the PC group. Conclusions Gamma-oryzanol rich fraction showed potential antioxidant activity greater than OR in the regulation of antioxidants and oxidative stress gene markers. PMID:20331906

Ketosteroid Standardized Cissus quadrangularis L. Extract and its Anabolic Activity: Time to Look Beyond Ketosteroid?

PubMed

Jadhav, Atul N; Rafiq, Mohammed; Devanathan, Rajendran; Azeemuddin, Mohammed; Anturlikar, Suryakanth D; Ahmed, Akhil; Sundaram, Ramchandran; Babu, U V; Paramesh, Rangesh

2016-05-01

Cissus quadrangularis (CQ) L. reported to contain 3-ketosteroids and have bone health benefits. This study aimed at establishing the relationship between the ketosteroid content and anabolic as well as bone health-promoting activities of various Cissus extracts in well-established orchidectomized (ORX) rat model. Supercritical carbon dioxide, ethyl acetate, and aqueous extracts (AE) of CQ L. were prepared and standardized for ketosteroid content by two methods used in commerce. Moreover, ketosteroid standardized extracts of this plant were evaluated for anabolic activity in rats in well-established ORX rat model. The increase in the absolute weight was appreciable in the CQ-AE treated group. Similarly, with respect to bone parameters, a similar trend was seen. The mean bone density, strength, and calcium content were found to be highest in the group treated with CQ-AE compared to groups treated with other extracts. This study reveals for the first time that 3-ketosteroids are not linked to the beneficial activities on bone and highlights the need for extensive characterization of biological active principles from CQ L. In light of the above estimation studies, we believe that current standardization of Cissus extraction "3-ketosteroids" is incorrect. We also did not find any report suggesting the presence of androgenic steroids in this plant and hence the characterization based on "3-ketosteroids" is scientifically incorrect. This study highlights the insufficient understanding of biological active principles from CQ L. and underlines the need for extensive bioactivity guided studies. Cissus quadrangularis (CQ) L. reported to contain 3.ketosteroids and have bone health benefitsWe did not find correlation between ketosteroid content obtained by conventional methods and its biological effectStudies indicate that claims of ketosteroid content need not necessarily correlate to biological effects and hence warrants extensive phytochemical characterization of biological active principles from CQ L. Abbreviations used: CQ: Cissus quadrangularis, ORX: Orchidectomized, AE: Aqueous extract, EE: Ethyl acetate extract, SFE: Supercritical fluid extract.

Near-infrared dental imaging using scanning fiber endoscope

NASA Astrophysics Data System (ADS)

Zhou, Yaxuan; Lee, Robert; Sadr, Alireza; Seibel, Eric J.

2018-02-01

Near-infrared (NIR) wavelength range of 1300-1500nm has the potential to outperform or augment other dental imaging modalities such as fluorescence imaging, owing to its lower scattering coefficient in enamel and trans- parency on stains and non-cariogenic plaque. However, cameras in this wavelength range are bulky and expensive, which lead to difficulties for in-vivo use and commercialization. Thus, we have proposed a new imaging device combining the scanning fiber endoscopy (SFE) and NIR imaging technology. The NIR SFE system has the advantage of miniature size (1.6 mm), flexible shaft, video frame rate (7Hz) and expandable wide field-of-view (60 degrees). Eleven extracted human teeth with or without occlusal caries were scanned by micro-computed X-ray tomography (micro-CT) to obtain 3D micro-CT images, which serve as the standard for comparison. NIR images in reflection mode were then taken on all the occlusal surfaces, using 1310nm super luminescent diode and 1460nm laser diode respectively. Qualitative comparison was performed between near-infrared im- ages and micro-CT images. Enamel demineralization in NIR appeared as areas of increased reflectivity, and distinguished from non-carious staining at the base of occlusal fissures or developmental defects on cusps. This preliminary work presented proof for practicability of combining NIR imaging technology with SFE for reliable and noninvasive dental imaging with miniaturization and low cost.

Projected changes in snowfall extremes and interannual variability of snowfall in the western United States

NASA Astrophysics Data System (ADS)

Lute, A. C.; Abatzoglou, J. T.; Hegewisch, K. C.

2015-02-01

Projected warming will have significant impacts on snowfall accumulation and melt, with implications for water availability and management in snow-dominated regions. Changes in snowfall extremes are confounded by projected increases in precipitation extremes. Downscaled climate projections from 20 global climate models were bias-corrected to montane Snowpack Telemetry stations across the western United States to assess mid-21st century changes in the mean and variability of annual snowfall water equivalent (SFE) and extreme snowfall events, defined by the 90th percentile of cumulative 3 day SFE amounts. Declines in annual SFE and number of snowfall days were projected for all stations. Changes in the magnitude of snowfall event quantiles were sensitive to historical winter temperature. At climatologically cooler locations, such as in the Rocky Mountains, changes in the magnitude of snowfall events mirrored changes in the distribution of precipitation events, with increases in extremes and less change in more moderate events. By contrast, declines in snowfall event magnitudes were found for all quantiles in warmer locations. Common to both warmer and colder sites was a relative increase in the magnitude of snowfall extremes compared to annual SFE and a larger fraction of annual SFE from snowfall extremes. The coefficient of variation of annual SFE increased up to 80% in warmer montane regions due to projected declines in snowfall days and the increased contribution of snowfall extremes to annual SFE. In addition to declines in mean annual SFE, more frequent low-snowfall years and less frequent high-snowfall years were projected for every station.

Supercritical carbon dioxide extraction as a predictor of polycyclic aromatic hydrocarbon bioaccumulation and toxicity by earthworms in manufactured-gas plant site soils.

PubMed

Kreitinger, Joseph P; Quiñones-Rivera, Antonio; Neuhauser, Edward F; Alexander, Martin; Hawthorne, Steven B

2007-09-01

The toxicity and uptake of polycyclic aromatic hydrocarbons (PAHs) by earthworms were measured in soil samples collected from manufactured-gas plant sites having a wide range in PAH concentrations (170-42,000 mg/kg) and soil characteristics. Samples varied from vegetated soils to pure lampblack soot and had total organic carbon contents ranging from 3 to 87%. The biota-soil accumulation factors (BSAFs) observed for individual PAHs in field-collected earthworms (Aporrectodea caliginosa) were up to 50-fold lower than the BSAFs predicted using equilibrium-partitioning theory. Acute toxicity to the earthworm Eisenia fetida was unrelated to total PAH concentration: Mortality was not observed in some soils having high concentrations of total PAHs (>42,000 mg/kg), whereas 100% mortality was observed in other soils having much lower concentrations of total PAHs (1,520 mg/kg). Instead, toxicity appeared to be related to the rapidly released fraction of PAHs determined by mild supercritical CO2 extraction (SFE). The results demonstrate that soils having approximately 16,000 mg rapidly released total PAH/kg organic carbon can be acutely toxic to earthworms and that the concentration of PAHs in soil that is rapidly released by SFE can estimate toxicity to soil invertebrates.

Dried Out: Phytoplankton Drought Response in the San Francisco Estuary

NASA Astrophysics Data System (ADS)

Dawson, T.; Houskeeper, H. F.; Palacios, S. L.; Peacock, M.; Kudela, R. M.

2017-12-01

Between 2012 and 2016, the state of California experienced one of the most severe multiyear droughts in nearly 120 years, causing a drastic reduction of freshwater flow to the San Francisco Estuary (SFE). During this period, retention by dams, coupled with the lack of winter rains and spring snow melt led to roughly a third less water reaching the SFE. Decreased freshwater flow to the bay alters the ecology of the SFE, for example by advancing the seasonal timing of phytoplankton blooms, and has been linked to phytoplankton plumes of different, and often more toxic, species. Phytoplankton functional type (PFT) methods, such as PHYDOtax, enable the measurement of community composition, and has been validated in SFE. As part of the NASA Student Airborne Research Program (SARP), we test the accuracy of the PHYDOtax algorithm during the drought period in SFE using matchups between in situ pigment measurements and remotely sensed reflectance spectra from the AVIRIS airborne sensor. We will present time series of salinity and phytoplankton composition in the SFE and evaluate the effects of the drought on the estuarine phytoplankton composition. In the future, California is expected to experience increased frequency of extreme weather events, such as drought, as a consequence of climate change. We evaluate the consequences of the drought on phytoplankton community composition to understand how future extreme weather events may alter the ecology or toxicity of SFE.

Reductive Sequestration Of Pertechnetate (99TcO4–) By Nano Zerovalent Iron (nZVI) Transformed By Abiotic Sulfide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fan, Dimin; Anitori, Roberto; Tebo, Bradley M.

2013-04-24

Under anoxic conditions, soluble 99TcO4– can be reduced to less soluble TcO2•nH2O, but the oxide is highly susceptible to reoxidation. Here we investigate an alternative strategy for remediation of Tc-contaminated groundwater whereby sequestration as Tc sulfide is favored by sulfidic conditions stimulated by nano zero-valent iron (nZVI). nZVI was pre-exposed to increasing concentrations of sulfide in simulated Hanford groundwater for 24 hrs to mimic the stages of aquifer sulfate reduction and onset of biotic sulfidogenesis. Solid-phase characterizations of the sulfidated nZVI confirmed the formation of nanocrystalline FeS phases, but higher S/Fe ratios (>0.112) did not result in the formation ofmore » significantly more FeS. The kinetics of Tc sequestration by these materials showed faster Tc removal rates with increasing S/Fe between S/Fe = 0–0.056, but decreasing Tc removal rates with S/Fe > 0.224. The more favorable Tc removal kinetics at low S/Fe could be due to a higher affinity of TcO4– for FeS (over iron oxides), and electron microscopy confirmed that the majority of the Tc was associated with FeS phases. The inhibition of Tc removal at high S/Fe appears to have been caused by excess HS–. X-ray absorption spectroscopy revealed that as S/Fe increased, Tc speciation shifted from TcO2•nH2O to TcS2. The most substantial change of Tc speciation occurred at low S/Fe, coinciding with the rapid increase of Tc removal rate. This agreement further confirms the importance of FeS in Tc sequestration.« less

[Optimization for supercritical CO2 extraction with response surface methodology and component analysis of Sapindus mukorossi oil].

PubMed

Wu, Yan; Xiao, Xin-yu; Ge, Fa-huan

2012-02-01

To study the extraction conditions of Sapindus mukorossi oil by Supercritical CO2 Extraction and identify its components. Optimized SFE-CO2 Extraction by response surface methodology and used GC-MS to analysie Sapindus mukorossi oil compounds. Established the model of an equation for the extraction rate of Sapindus mukorossi oil by Supercritical CO2 Extraction, and the optimal parameters for the Supercritical CO2 Extraction determined by the equation were: the extraction pressure was 30 MPa, temperature was 40 degrees C; The separation I pressure was 14 MPa, temperature was 45 degrees C; The separation II pressure was 6 MPa, temperature was 40 degrees C; The extraction time was 60 min and the extraction rate of Sapindus mukorossi oil of 17.58%. 22 main compounds of Sapindus mukorossi oil extracted by supercritical CO2 were identified by GC-MS, unsaturated fatty acids were 86.59%. This process is reliable, safe and with simple operation, and can be used for the extraction of Sapindus mukorossi oil.

Composition-dependence of stacking fault energy in austenitic stainless steels through linear regression with random intercepts

NASA Astrophysics Data System (ADS)

Meric de Bellefon, G.; van Duysen, J. C.; Sridharan, K.

2017-08-01

The stacking fault energy (SFE) plays an important role in deformation behavior and radiation damage of FCC metals and alloys such as austenitic stainless steels. In the present communication, existing expressions to calculate SFE in those steels from chemical composition are reviewed and an improved multivariate linear regression with random intercepts is used to analyze a new database of 144 SFE measurements collected from 30 literature references. It is shown that the use of random intercepts can account for experimental biases in these literature references. A new expression to predict SFE from austenitic stainless steel compositions is proposed.

Nitrogen in chromium-manganese stainless steels: a review on the evaluation of stacking fault energy by computational thermodynamics.

PubMed

Mosecker, Linda; Saeed-Akbari, Alireza

2013-06-01

Nitrogen in austenitic stainless steels and its effect on the stacking fault energy (SFE) has been the subject of intense discussions in the literature. Until today, no generally accepted method for the SFE calculation exists that can be applied to a wide range of chemical compositions in these systems. Besides different types of models that are used from first-principle to thermodynamics-based approaches, one main reason is the general lack of experimentally measured SFE values for these steels. Moreover, in the respective studies, not only different alloying systems but also different domains of nitrogen contents were analyzed resulting in contrary conclusions on the effect of nitrogen on the SFE. This work gives a review on the current state of SFE calculation by computational thermodynamics for the Fe-Cr-Mn-N system. An assessment of the thermodynamic effective Gibbs free energy, [Formula: see text], model for the [Formula: see text] phase transformation considering existing data from different literature and commercial databases is given. Furthermore, we introduce the application of a non-constant composition-dependent interfacial energy, б γ / ε , required to consider the effect of nitrogen on SFE in these systems.

Nitrogen in chromium–manganese stainless steels: a review on the evaluation of stacking fault energy by computational thermodynamics

PubMed Central

Mosecker, Linda; Saeed-Akbari, Alireza

2013-01-01

Nitrogen in austenitic stainless steels and its effect on the stacking fault energy (SFE) has been the subject of intense discussions in the literature. Until today, no generally accepted method for the SFE calculation exists that can be applied to a wide range of chemical compositions in these systems. Besides different types of models that are used from first-principle to thermodynamics-based approaches, one main reason is the general lack of experimentally measured SFE values for these steels. Moreover, in the respective studies, not only different alloying systems but also different domains of nitrogen contents were analyzed resulting in contrary conclusions on the effect of nitrogen on the SFE. This work gives a review on the current state of SFE calculation by computational thermodynamics for the Fe–Cr–Mn–N system. An assessment of the thermodynamic effective Gibbs free energy, , model for the phase transformation considering existing data from different literature and commercial databases is given. Furthermore, we introduce the application of a non-constant composition-dependent interfacial energy, бγ/ε, required to consider the effect of nitrogen on SFE in these systems. PMID:27877573

Substrate-Independent Surface Energy Tuning via Siloxane Treatment for Printed Electronics.

PubMed

Schlisske, Stefan; Held, Martin; Rödlmeier, Tobias; Menghi, Silvia; Fuchs, Kathleen; Ruscello, Marta; Morfa, Anthony J; Lemmer, Uli; Hernandez-Sosa, Gerardo

2018-05-29

Digital printing enables solution processing of functional materials and opens a new route to fabricate low-cost electronic devices. One crucial parameter that affects the wettability of inks for all printing techniques is the surface free energy (SFE) of the substrate. Siloxanes, with their huge variety of side chains and their ability to form self-assembled monolayers, offer exhaustive control of the substrate SFE from hydrophilic to hydrophobic. Thus, siloxane treatment is a suitable approach to adjust the substrate conditions to the desired ink, instead of optimizing the ink to an arbitrary substrate. In this work, the influence of different fluorinated and nonfluorinated siloxanes on the SFE of different substrates, such as polymers, glasses, and metals, are examined. By mixing several siloxanes, we demonstrate the fine tuning of the surface energy. The polar and dispersive components of the SFE are determined by the Owens-Wendt-Rabel-Kaelble (OWRK) method. Furthermore, the impact of the siloxanes and therefore the SFE on the pinning of droplets and wet films are assessed via dynamic contact angle measurements. SFE-optimized substrates enable tailoring the resolution of inkjet printed silver structures. A nanoparticulate silver ink was used for printing single drops, lines, and source-drain electrodes for transistors. These were examined in terms of diameter, edge quality, and functionality. We show that by adjusting the SFE of an arbitrary substrate, the printed resolution is substantially increased by minimizing the printed drop size by up to 70%.

ENERGY CONVERSION FOR THE TRANSITION FROM Al TO γ-Al2O3 NANOPARTICLES

NASA Astrophysics Data System (ADS)

Wang, Shulin; Li, Shengjuan; Xu, Bo; Jian, Dunliang; Zhu, Yufang

2013-07-01

We have successfully converted large volume Al particles into γ-Al2O3 nanostructures by vibration milling at room temperature and successive treatment. We show that there exist special relationships among stacking fault energy (SFE), strain energy (SRE), and surface energy (SE) of the materials, including interdependence, intercompetition, and interconversion during the phase transition. SFE and SRE perform the same changing tendency, while SE just does the opposite. However, it is not the particle size but the energy state that determines the reactivity of the materials. And it is the SE that can directly determine the physical chemical reaction and the conversion into the end product rather than SFE and SRE. When SE goes up, the material reactivity and the product yield will be enhanced; and when SE goes down, the reaction and the product yield will decay. However, the state of SE depends closely on the change tendency of the SFE and SRE. That is, when SFE and SRE goes up, SE will goes down; if SFE and SRE goes down, SE will goes up. It seems that energy conservation law may be followed in a sense in the particle system if the external input keeps constant. The work may be significant for energy conversion in nano-scale and mechanosynthesis of oxide nanoparticles.

Environmental application of millimeter-scale sponge iron (s-Fe(0)) particles (II): the effect of surface copper.

PubMed

Ju, Yongming; Liu, Xiaowen; Liu, Runlong; Li, Guohua; Wang, Xiaoyan; Yang, Yanyan; Wei, Dongyang; Fang, Jiande; Dionysiou, Dionysios D

2015-04-28

To enhance the catalytic reactivity of millimeter-scale particles of sponge iron (s-Fe(0)), Cu(2+) ions were deposited on the surface of s-Fe(0) using a simple direct reduction reaction, and the catalytic properties of the bimetallic system was tested for removal of rhodamine B (RhB) from an aqueous solution. The influence of Cu(0) loading, catalyst dosage, particle size, initial RhB concentration, and initial pH were investigated, and the recyclability of the catalyst was also assessed. The results demonstrate that the 3∼5 millimeter s-Fe(0) particles (s-Fe(0)(3∼5mm)) with 5wt% Cu loading gave the best results. The removal of RhB followed two-step, pseudo-first-order reaction kinetics. Cu(0)-s-Fe(0) showed excellent stability after five reuse cycles. Cu(0)-s-Fe(0) possesses great advantages compared to nanoscale zero-valent iron, iron power, and iron flakes as well as its bimetals. The surface Cu(0) apparently catalyzes the production of reactive hydrogen atoms for indirect reaction and generates Fe-Cu galvanic cells that enhance electron transfer for direct reaction. This bimetallic catalyst shows great potential for the pre-treatment of recalcitrant wastewaters. Additionally, some oxides containing iron element are selected to simulate the adsorption process. The results prove that the adsorption process of FeOOH, Fe2O3 and Fe3O4 played minor role for the removal of RhB. Copyright © 2015 Elsevier B.V. All rights reserved.

Pretreatment of water-based seed coating wastewater by combined coagulation and sponge-iron-catalyzed ozonation technology.

PubMed

Wen, Chen; Xu, Xiaoyi; Fan, Yunshuang; Xiao, Changfa; Ma, Cong

2018-05-04

Coagulation-sedimentation combined with sponge iron/ozone (CS-SFe/O 3 ) technology was applied to pretreat water-based seed coating wastewater (WSCW) from pesticide manufacturing. Coagulation with polyferric sulfate at a dosage of 1.5 g L -1 and a pH of 8.0 was effective, with color and chemical oxygen demand (COD) removal rates of 96.8 and 83.4%, respectively. SFe/O 3 treatment further reduced the organic content in the effluents, especially concerning the degradation of aromatic pollutants, as demonstrated via ultraviolet-visible spectrophotometry (UV-vis), excitation-emission matrix (EEM) fluorescence spectrometry, and gas chromatography-mass spectrometry (GC/MS) analyses. The residual color and COD values of the effluent were 581.0 times and 640.0 mg L -1 , respectively, under optimal conditions (ozone concentration of 0.48 mg L -1 , SFe dosage of 20.0 g L -1 , initial pH of 9.0, and reaction time of 30 min). Organic pollutants were also degraded by the high amounts of HO, which may have been generated via the transformation of ozone into HO on the SFe's surface and in the solution. Meanwhile, the biochemical oxygen demand (BOD 5 )/COD ratio of the WSCW increased, which indicates that the biodegradability improved significantly. The amount of iron leached from SFe particles was 4.5 mg L -1 , which shows that the SFe catalyst has good stability. The operating cost of the combined CS-SFe/O 3 technology was estimated at approximately 2.79 USD t -1 . The results of this study suggest that the application of the combined CS-SFe/O 3 technology in WSCW pretreatment can be beneficial for removing suspended solids, degrading recalcitrant pollutants, and enhancing biodegradability for the subsequent bioprocessing treatment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Scanning Fiber Endoscope Improves Detection of 5-Aminolevulinic Acid-Induced Protoporphyrin IX Fluorescence at the Boundary of Infiltrative Glioma.

PubMed

Belykh, Evgenii; Miller, Eric J; Hu, Danying; Martirosyan, Nikolay L; Woolf, Eric C; Scheck, Adrienne C; Byvaltsev, Vadim A; Nakaji, Peter; Nelson, Leonard Y; Seibel, Eric J; Preul, Mark C

2018-05-01

Fluorescence-guided surgery with protoporphyrin IX (PpIX) as a photodiagnostic marker is gaining acceptance for resection of malignant gliomas. Current wide-field imaging technologies do not have sufficient sensitivity to detect low PpIX concentrations. We evaluated a scanning fiber endoscope (SFE) for detection of PpIX fluorescence in gliomas and compared it to an operating microscope (OPMI) equipped with a fluorescence module and to a benchtop confocal laser scanning microscope (CLSM). 5-Aminolevulinic acid-induced PpIX fluorescence was assessed in GL261-Luc2 cells in vitro and in vivo after implantation in mouse brains, at an invading glioma growth stage, simulating residual tumor. Intraoperative fluorescence of high and low PpIX concentrations in normal brain and tumor regions with SFE, OPMI, CLSM, and histopathology were compared. SFE imaging of PpIX correlated to CLSM at the cellular level. PpIX accumulated in normal brain cells but significantly less than in glioma cells. SFE was more sensitive to accumulated PpIX in fluorescent brain areas than OPMI (P < 0.01) and dramatically increased imaging time (>6×) before tumor-to-background contrast was diminished because of photobleaching. SFE provides new endoscopic capabilities to view PpIX-fluorescing tumor regions at cellular resolution. SFE may allow accurate imaging of 5-aminolevulinic acid labeling of gliomas and other tumor types when current detection techniques have failed to provide reliable visualization. SFE was significantly more sensitive than OPMI to low PpIX concentrations, which is relevant to identifying the leading edge or metastasizing cells of malignant glioma or to treating low-grade gliomas. This new application has the potential to benefit surgical outcomes. Copyright © 2018 Elsevier Inc. All rights reserved.

Microstructure and mechanical characteristics of gradient structured Cu and Cu alloys processed by surface mechanical attrition treatment

NASA Astrophysics Data System (ADS)

Hu, XZ; Cheng, LP; Chen, HL; Yin, Z.; Zhang, Z.; Shu, BP; Gong, YL; Zhu, XK

2017-05-01

Cu-Al-Zn alloys with different stacking fault energy (SFE) were processed by surface mechanical attrition treatment (SMAT) at cryogenic temperature (CT), mechanical properties of gradient structured Cu-Al-Zn alloys were investigated in this study. Al and Zn content in alloys, which result in the decrease of SFE, can contribute to the increase in strength. Cu-4.5wt%Al-14.3wt%Zn alloy with the lower SFE shows that the strength increased, the ductility did not decrease significantly with increasing processing time, and the strength can be improved by a thicker gradient structure (GS) layer. The better combination of strength and ductility was achieved in Cu-4.5wt%Al-14.3wt%Zn alloy with lower SFE.

In Situ Nanoindentation Studies on Detwinning and Work Hardening in Nanotwinned Monolithic Metals

DOE PAGES

Liu, Y.; Li, N.; Bufford, D.; ...

2015-07-14

Certain nanotwinned (nt) metals have rare combinations of high mechanical strength and ductility. Here, we review recent in situ nanoindentation studies (using transmission electron microscopes) on the deformation mechanisms of nt face-centered cubic metals including Cu, Ni, and Al with a wide range of stacking fault energy (SFE). Moreover, in nt Cu with low-to-intermediate SFE, detwinning (accompanied by rapid twin boundary migration) occurs at ultralow stress. In Ni with relatively high SFE, coherent {111} twin boundaries lead to substantial work hardening. Twinned Al has abundant {112} incoherent twin boundaries, which induce significant work-hardening capability and plasticity in Al. Finally, twinmore » boundaries in Al also migrate but at very high stresses. Furthermore, molecular dynamics simulations reveal the influence of SFE on deformation mechanisms in twinned metals.« less

Basic criteria for formation of growth twins in high stacking fault energy metals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, K. Y.; Zhang, X.; Department of Mechanical Engineering, Texas A and M University, College Station, Texas 77843

Nanotwinned metals received significant interest lately as twin boundaries may enable simultaneous enhancement of strength, ductility, thermal stability, and radiation tolerance. However, nanotwins have been the privilege of metals with low-to-intermediate stacking fault energy (SFE). Recent scattered studies show that nanotwins could be introduced into high SFE metals, such as Al. In this paper, we examine several sputter-deposited, (111) textured Ag/Al, Cu/Ni, and Cu/Fe multilayers, wherein growth twins were observed in Al, Ni, and face-centered cubic (fcc) Fe. The comparisons lead to two important design criteria that dictate the introduction of growth twins in high SFE metals. The validity ofmore » these criteria was then examined in Ag/Ni multilayers. Furthermore, another twin formation mechanism in high SFE metals was discovered in Ag/Ni system.« less

A reference-modified density functional theory: An application to solvation free-energy calculations for a Lennard-Jones solution.

PubMed

Sumi, Tomonari; Maruyama, Yutaka; Mitsutake, Ayori; Koga, Kenichiro

2016-06-14

In the conventional classical density functional theory (DFT) for simple fluids, an ideal gas is usually chosen as the reference system because there is a one-to-one correspondence between the external field and the density distribution function, and the exact intrinsic free-energy functional is available for the ideal gas. In this case, the second-order density functional Taylor series expansion of the excess intrinsic free-energy functional provides the hypernetted-chain (HNC) approximation. Recently, it has been shown that the HNC approximation significantly overestimates the solvation free energy (SFE) for an infinitely dilute Lennard-Jones (LJ) solution, especially when the solute particles are several times larger than the solvent particles [T. Miyata and J. Thapa, Chem. Phys. Lett. 604, 122 (2014)]. In the present study, we propose a reference-modified density functional theory as a systematic approach to improve the SFE functional as well as the pair distribution functions. The second-order density functional Taylor series expansion for the excess part of the intrinsic free-energy functional in which a hard-sphere fluid is introduced as the reference system instead of an ideal gas is applied to the LJ pure and infinitely dilute solution systems and is proved to remarkably improve the drawbacks of the HNC approximation. Furthermore, the third-order density functional expansion approximation in which a factorization approximation is applied to the triplet direct correlation function is examined for the LJ systems. We also show that the third-order contribution can yield further refinements for both the pair distribution function and the excess chemical potential for the pure LJ liquids.

Development of a new extraction technique and HPLC method for the analysis of non-psychoactive cannabinoids in fibre-type Cannabis sativa L. (hemp).

PubMed

Brighenti, Virginia; Pellati, Federica; Steinbach, Marleen; Maran, Davide; Benvenuti, Stefania

2017-09-05

The present work was aimed at the development and validation of a new, efficient and reliable technique for the analysis of the main non-psychoactive cannabinoids in fibre-type Cannabis sativa L. (hemp) inflorescences belonging to different varieties. This study was designed to identify samples with a high content of bioactive compounds, with a view to underscoring the importance of quality control in derived products as well. Different extraction methods, including dynamic maceration (DM), ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE) and supercritical-fluid extraction (SFE) were applied and compared in order to obtain a high yield of the target analytes from hemp. Dynamic maceration for 45min with ethanol (EtOH) at room temperature proved to be the most suitable technique for the extraction of cannabinoids in hemp samples. The analysis of the target analytes in hemp extracts was carried out by developing a new reversed-phase high-performance liquid chromatography (HPLC) method coupled with diode array (UV/DAD) and electrospray ionization-mass spectrometry (ESI-MS) detection, by using an ion trap mass analyser. An Ascentis Express C 18 column (150mm×3.0mm I.D., 2.7μm) was selected for the HPLC analysis, with a mobile phase composed of 0.1% formic acid in both water and acetonitrile, under gradient elution. The application of the fused-core technology allowed us to obtain a significant improvement of the HPLC performance compared with that of conventional particulate stationary phases, with a shorter analysis time and a remarkable reduction of solvent usage. The analytical method optimized in this study was fully validated to show compliance with international requirements. Furthermore, it was applied to the characterization of nine hemp samples and six hemp-based pharmaceutical products. As such, it was demonstrated to be a very useful tool for the analysis of cannabinoids in both the plant material and its derivatives for pharmaceutical and nutraceutical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Cocrystal solubilization in biorelevant media and its prediction from drug solubilization

PubMed Central

Lipert, Maya P.; Roy, Lilly; Childs, Scott L.

2015-01-01

This work examines cocrystal solubility in biorelevant media, (FeSSIF, fed state simulated intestinal fluid), and develops a theoretical framework that allows for the simple and quantitative prediction of cocrystal solubilization from drug solubilization. The solubilities of four hydrophobic drugs and seven cocrystals containing these drugs were measured in FeSSIF and in acetate buffer at pH 5.00. In all cases, the cocrystal solubility (Scocrystal) was higher than the drug solubility (Sdrug) in both buffer and FeSSIF; however, the solubilization ratio of drug, SRdrug = (SFeSSIF/Sbuffer)drug, was not the same as the solubilization ratio of cocrystal, SRcocrystal = (SFeSSIF/Sbuffer)cocrystal, meaning drug and cocrystal were not solubilized to the same extent in FeSSIF. This highlights the potential risk of anticipating cocrystal behavior in biorelevant media based on solubility studies in water. Predictions of SRcocrystal from simple equations based only on SRdrug were in excellent agreement with measured values. For 1:1 cocrystals, the cocrystal solubilization ratio can be obtained from the square root of the drug solubilization ratio. For 2:1 cocrystals, SRcocrystal is found from (SRdrug)2/3. The findings in FeSSIF can be generalized to describe cocrystal behavior in other systems involving preferential solubilization of a drug such as surfactants, lipids, and other drug solubilizing media. PMID:26390213

Development and testing of the Survey of Family Environment (SFE): a novel instrument to measure family functioning and needs for family support.

PubMed

Hohashi, Naohiro; Honda, Junko

2012-01-01

Hohashi's Concentric Sphere Family Environment Model (CSFEM; Hohashi & Honda, 2011) is a newly proposed family nursing theory for holistically understanding the family environment that acts on family well-being. The purpose of this article is to develop and psychometrically test the Japanese version of the Survey of Family Environment (SFE-J), grounded in the CSFEM, for measuring family's perceived family functioning and family's perceived needs for family support. The SFE-J is a 30-item self-administered instrument that assesses five domains (suprasystem, macrosystem, microsystem, family internal environment system, and chronosystem) and has been subjected to rigorous reliability and validity investigations among paired partners in child-rearing families (N of family = 1,990). Internal consistency reliability was high as measured by Cronbach's alpha coefficients. Temporal stability over a 2-week interval was supported by high (substantial or perfect) and significant intraclass correlation coefficients. The total score for the SFE-J was significantly correlated with the Japanese version of the Feetham Family Functioning Survey (FFFS-J), indicating an acceptable concurrent validity. Construct validity was supported by a confirmatory factor analysis that evaluated the five-factor structure to measure the concept of CSFEM. Results also demonstrate that the SFE-J family functioning scores show no significant differences between paired partners. The SFE-J is a reliable and valid instrument to assess not only intrafamily functioning but also interfamily functioning and, by identifying items/domains with high requirements for family support, serves to facilitate the providing of appropriate support to families.

Various extraction and analytical techniques for isolation and identification of secondary metabolites from Nigella sativa seeds.

PubMed

Liu, X; Abd El-Aty, A M; Shim, J-H

2011-10-01

Nigella sativa L. (black cumin), commonly known as black seed, is a member of the Ranunculaceae family. This seed is used as a natural remedy in many Middle Eastern and Far Eastern countries. Extracts prepared from N. sativa have, for centuries, been used for medical purposes. Thus far, the organic compounds in N. sativa, including alkaloids, steroids, carbohydrates, flavonoids, fatty acids, etc. have been fairly well characterized. Herein, we summarize some new extraction techniques, including microwave assisted extraction (MAE) and supercritical extraction techniques (SFE), in addition to the classical method of hydrodistillation (HD), which have been employed for isolation and various analytical techniques used for the identification of secondary metabolites in black seed. We believe that some compounds contained in N. sativa remain to be identified, and that high-throughput screening could help to identify new compounds. A study addressing environmentally-friendly techniques that have minimal or no environmental effects is currently underway in our laboratory.

Influence of Application Time and Etching Mode of Universal Adhesives on Enamel Adhesion.

PubMed

Sai, Keiichi; Takamizawa, Toshiki; Imai, Arisa; Tsujimoto, Akimasa; Ishii, Ryo; Barkmeier, Wayne W; Latta, Mark A; Miyazaki, Masashi

2018-01-01

To investigate the influence of application time and etching mode of universal adhesives on enamel adhesion. Five universal adhesives, Adhese Universal, Bondmer Lightless, Clearfil Universal Bond Quick, G-Premio Bond, and Scotchbond Universal, were used. Bovine incisors were prepared and divided into four groups of ten teeth each. SBS, Ra, and SFE were determined after the following procedures: 1. self-etch mode with immediate air blowing after application (IA); 2. self-etch mode with prolonged application time (PA); 3. etch-and-rinse mode with IA; 4. etch-and-rinse mode with PA. After 24-h water storage, the bonded assemblies were subjected to shear bond strength (SBS) tests. For surface roughness (Ra) and surface free energy (SFE) measurements, the adhesives were simply applied to the enamel and rinsed with acetone and water before the measurements were carried out. Significantly higher SBS and Ra values were obtained with etch-and-rinse mode than with self-etch mode regardless of the application time or type of adhesive. Although most adhesives showed decreased SFE values with increased application time in self-etch mode, SFE values in etch-and-rinse mode were dependent on the adhesive type and application time. Etching mode, application time, and type of adhesive significantly influenced the SBS, Ra, and SFE values.

Application of gas chromatography to analysis of spirit-based alcoholic beverages.

PubMed

Wiśniewska, Paulina; Śliwińska, Magdalena; Dymerski, Tomasz; Wardencki, Waldemar; Namieśnik, Jacek

2015-01-01

Spirit-based beverages are alcoholic drinks; their production processes are dependent on the type and origin of raw materials. The composition of this complex matrix is difficult to analyze, and scientists commonly choose gas chromatography techniques for this reason. With a wide selection of extraction methods and detectors it is possible to provide qualitative and quantitative analysis for many chemical compounds with various functional groups. This article describes different types of gas chromatography techniques and their most commonly used associated extraction techniques (e.g., LLE, SPME, SPE, SFE, and SBME) and detectors (MS, TOFMS, FID, ECD, NPD, AED, O or EPD). Additionally, brief characteristics of internationally popular spirit-based beverages and application of gas chromatography to the analysis of selected alcoholic drinks are presented.

Spectrally enhanced image resolution of tooth enamel surfaces

NASA Astrophysics Data System (ADS)

Zhang, Liang; Nelson, Leonard Y.; Berg, Joel H.; Seibel, Eric J.

2012-01-01

Short-wavelength 405 nm laser illumination of surface dental enamel using an ultrathin scanning fiber endoscope (SFE) produced enhanced detail of dental topography. The surfaces of human extracted teeth and artificial erosions were imaged with 405 nm, 444 nm, 532 nm, or 635 nm illumination lasers. The obtained images were then processed offline to compensate for any differences in the illumination beam diameters between the different lasers. Scattering and absorption coefficients for a Monte Carlo model of light propagation in dental enamel for 405 nm were scaled from published data at 532 nm and 633 nm. The value of the scattering coefficient used in the model was scaled from the coefficients at 532 nm and 633 nm by the inverse third power of wavelength. Simulations showed that the penetration depth of short-wavelength illumination is localized close to the enamel surface, while long-wavelength illumination travels much further and is backscattered from greater depths. Therefore, images obtained using short wavelength laser are not contaminated by the superposition of light reflected from enamel tissue at greater depths. Hence, the SFE with short-wavelength illumination may make it possible to visualize surface manifestations of phenomena such as demineralization, thus better aiding the clinician in the detection of early caries.

Environmental application of millimetre-scale sponge iron (s-Fe0) particles (IV): New insights into visible light photo-Fenton-like process with optimum dosage of H2O2 and RhB photosensitizers.

PubMed

Ju, Yongming; Yu, Yunjiang; Wang, Xiaoyan; Xiang, Mingdeng; Li, Liangzhong; Deng, Dongyang; Dionysiou, Dionysios D

2017-02-05

In this study, we firstly develop the photo-Fenton-like system with millimetric sponge iron (s-Fe 0 ), H 2 O 2 , visible light (vis, λ≥420nm) and rhodamine B (RhB), and present a comprehensive study concerning the mechanism. Thus, we investigate (1) the adsorption of RhB onto s-Fe 0 , (2) the photo-Fenton-like removal of RhB over iron oxides generated from the corrosion of s-Fe 0 , (3) the homogeneous photo-Fenton removal of RhB over Fe 2+ or Fe 3+ , (4) the Fe 3+ -RhB complexes, and (5) the photo-Fenton-like removal of tetrabromobisphenol A (TBBPA). The results show that neither the adsorption process over s-Fe 0 nor the photo-Fenton-like process over FeOOH, Fe 3 O 4 and Fe 2 O 3 , achieved efficient removal of RhB. For comparison, in homogeneous photo-Fenton process, the presence of Fe 3+ ions, rather than Fe 2+ ions, effectively eliminated RhB. Furthermore, the UV-vis spectra showing new absorbance at∼285nm indicate the complexes of RhB and Fe 3+ ions, adopting vis photons to form excited state and further eject one electron via ligand-to-metal charge-transfer to activate H 2 O 2 . Additionally, efficient TBBPA removal was obtained only in the presence of RhB. Accordingly, the s-Fe 0 - based photo-Fenton-like process assisted with dyestuff wastewater is promising for removing a series of persistent organic pollutants. Copyright © 2016 Elsevier B.V. All rights reserved.

Trends in snowfall versus rainfall in the western United States

USGS Publications Warehouse

Knowles, N.; Dettinger, M.D.; Cayan, D.R.

2006-01-01

The water resources of the western United States depend heavily on snowpack to store part of the wintertime precipitation into the drier summer months. A well-documented shift toward earlier runoff in recent decades has been attributed to 1) more precipitation falling as rain instead of snow and 2) earlier snowmelt. The present study addresses the former, documenting a regional trend toward smaller ratios of winter-total snowfall water equivalent (SFE) to winter-total precipitation (P) during the period 1949-2004. The trends toward reduce d SFE are a response to warming across the region, with the most significant reductions occurring where winter wet-day minimum temperatures, averaged over the study period, were warmer than -5??C. Most SFE reductions were associated with winter wet-day temperature increases between 0?? and +3??C over the study period. Warmings larger than this occurred mainly at sites where the mean temperatures were cool enough that the precipitation form was less susceptible to warming trends. The trends toward reduced SFE/P ratios w ere most pronounced in March regionwide and in January near the West Coast, corresponding, to widespread warming in these months. While mean temperatures in March were sufficiently high to allow the warming, trend to produce SFE/P declines across the study region, mean January temperatures were cooler. with the result that January SFE/P impacts were restricted to the lower elevations near the West Coast. Extending the analysis back to 1920 sho ws that although the trends presented here may be partially attributable to interdecadal climate variability associated with the Pacific decadal oscillation. they also appear to result from still longer-term climate shifts.

A low-complexity 2-point step size gradient projection method with selective function evaluations for smoothed total variation based CBCT reconstructions

NASA Astrophysics Data System (ADS)

Song, Bongyong; Park, Justin C.; Song, William Y.

2014-11-01

The Barzilai-Borwein (BB) 2-point step size gradient method is receiving attention for accelerating Total Variation (TV) based CBCT reconstructions. In order to become truly viable for clinical applications, however, its convergence property needs to be properly addressed. We propose a novel fast converging gradient projection BB method that requires ‘at most one function evaluation’ in each iterative step. This Selective Function Evaluation method, referred to as GPBB-SFE in this paper, exhibits the desired convergence property when it is combined with a ‘smoothed TV’ or any other differentiable prior. This way, the proposed GPBB-SFE algorithm offers fast and guaranteed convergence to the desired 3DCBCT image with minimal computational complexity. We first applied this algorithm to a Shepp-Logan numerical phantom. We then applied to a CatPhan 600 physical phantom (The Phantom Laboratory, Salem, NY) and a clinically-treated head-and-neck patient, both acquired from the TrueBeam™ system (Varian Medical Systems, Palo Alto, CA). Furthermore, we accelerated the reconstruction by implementing the algorithm on NVIDIA GTX 480 GPU card. We first compared GPBB-SFE with three recently proposed BB-based CBCT reconstruction methods available in the literature using Shepp-Logan numerical phantom with 40 projections. It is found that GPBB-SFE shows either faster convergence speed/time or superior convergence property compared to existing BB-based algorithms. With the CatPhan 600 physical phantom, the GPBB-SFE algorithm requires only 3 function evaluations in 30 iterations and reconstructs the standard, 364-projection FDK reconstruction quality image using only 60 projections. We then applied the algorithm to a clinically-treated head-and-neck patient. It was observed that the GPBB-SFE algorithm requires only 18 function evaluations in 30 iterations. Compared with the FDK algorithm with 364 projections, the GPBB-SFE algorithm produces visibly equivalent quality CBCT image for the head-and-neck patient with only 180 projections, in 131.7 s, further supporting its clinical applicability.

A low-complexity 2-point step size gradient projection method with selective function evaluations for smoothed total variation based CBCT reconstructions.

PubMed

Song, Bongyong; Park, Justin C; Song, William Y

2014-11-07

The Barzilai-Borwein (BB) 2-point step size gradient method is receiving attention for accelerating Total Variation (TV) based CBCT reconstructions. In order to become truly viable for clinical applications, however, its convergence property needs to be properly addressed. We propose a novel fast converging gradient projection BB method that requires 'at most one function evaluation' in each iterative step. This Selective Function Evaluation method, referred to as GPBB-SFE in this paper, exhibits the desired convergence property when it is combined with a 'smoothed TV' or any other differentiable prior. This way, the proposed GPBB-SFE algorithm offers fast and guaranteed convergence to the desired 3DCBCT image with minimal computational complexity. We first applied this algorithm to a Shepp-Logan numerical phantom. We then applied to a CatPhan 600 physical phantom (The Phantom Laboratory, Salem, NY) and a clinically-treated head-and-neck patient, both acquired from the TrueBeam™ system (Varian Medical Systems, Palo Alto, CA). Furthermore, we accelerated the reconstruction by implementing the algorithm on NVIDIA GTX 480 GPU card. We first compared GPBB-SFE with three recently proposed BB-based CBCT reconstruction methods available in the literature using Shepp-Logan numerical phantom with 40 projections. It is found that GPBB-SFE shows either faster convergence speed/time or superior convergence property compared to existing BB-based algorithms. With the CatPhan 600 physical phantom, the GPBB-SFE algorithm requires only 3 function evaluations in 30 iterations and reconstructs the standard, 364-projection FDK reconstruction quality image using only 60 projections. We then applied the algorithm to a clinically-treated head-and-neck patient. It was observed that the GPBB-SFE algorithm requires only 18 function evaluations in 30 iterations. Compared with the FDK algorithm with 364 projections, the GPBB-SFE algorithm produces visibly equivalent quality CBCT image for the head-and-neck patient with only 180 projections, in 131.7 s, further supporting its clinical applicability.

Modeling the Extremely Lightweight Zerodur Mirror (ELZM) Thermal Soak Test

NASA Technical Reports Server (NTRS)

Brooks, Thomas E.; Eng, Ron; Hull, Tony; Stahl, H. Philip

2017-01-01

Exoplanet science requires extreme wavefront stability (10 pm change/10 minutes), so every source of wavefront error (WFE) must be characterized in detail. This work illustrates the testing and characterization process that will be used to determine how much surface figure error (SFE) is produced by mirror substrate materials' CTE distributions. Schott's extremely lightweight Zerodur mirror (ELZM) was polished to a sphere, mounted, and tested at Marshall Space Flight Center (MSFC) in the X-Ray and Cryogenic Test Facility (XRCF). The test transitioned the mirror's temperature from an isothermal state at 292K to isothermal states at 275K, 250K and 230K to isolate the effects of the mirror's CTE distribution. The SFE was measured interferometrically at each temperature state and finite element analysis (FEA) has been completed to assess the predictability of the change in the mirror's surface due to a change in the mirror's temperature. The coefficient of thermal expansion (CTE) distribution in the ELZM is unknown, so the analysis has been correlated to the test data. The correlation process requires finding the sensitivity of SFE to a given CTE distribution in the mirror. A novel hand calculation is proposed to use these sensitivities to estimate thermally induced SFE. The correlation process was successful and is documented in this paper. The CTE map that produces the measured SFE is in line with the measured data of typical boules of Schott's Zerodur glass.

Modeling the Extremely Lightweight Zerodur Mirror (ELZM) thermal soak test

NASA Astrophysics Data System (ADS)

Brooks, Thomas E.; Eng, Ron; Hull, Tony; Stahl, H. Philip

2017-09-01

Exoplanet science requires extreme wavefront stability (10 pm change/10 minutes), so every source of wavefront error (WFE) must be characterized in detail. This work illustrates the testing and characterization process that will be used to determine how much surface figure error (SFE) is produced by mirror substrate materials' CTE distributions. Schott's extremely lightweight Zerodur mirror (ELZM) was polished to a sphere, mounted, and tested at Marshall Space Flight Center (MSFC) in the X-Ray and Cryogenic Test Facility (XRCF). The test transitioned the mirror's temperature from an isothermal state at 292K to isothermal states at 275K, 250K and 230K to isolate the effects of the mirror's CTE distribution. The SFE was measured interferometrically at each temperature state and finite element analysis (FEA) has been completed to assess the predictability of the change in the mirror's surface due to a change in the mirror's temperature. The coefficient of thermal expansion (CTE) distribution in the ELZM is unknown, so the analysis has been correlated to the test data. The correlation process requires finding the sensitivity of SFE to a given CTE distribution in the mirror. A novel hand calculation is proposed to use these sensitivities to estimate thermally induced SFE. The correlation process was successful and is documented in this paper. The CTE map that produces the measured SFE is in line with the measured data of typical boules of Schott's Zerodur glass.

Social Facilitation Expectancies for Smoking: Psychometric Properties of a New Measure

ERIC Educational Resources Information Center

Schweizer, C. Amanda; Doran, Neal; Myers, Mark G.

2014-01-01

Objective: Expectancies about social outcomes for smoking are relevant to college student smokers, who frequently report "social smoking." A new measure, the Social Facilitation Expectancies (SFE) scale, was developed to assess these beliefs. Participants: The SFE was administered to undergraduate college student smokers ("N" =…

Effect of sugar fatty acid esters on rumen fermentation in vitro.

PubMed

Wakita, M; Hoshino, S

1987-11-01

1. The effect of sugar fatty acid esters (SFEs; currently used as food additives for human consumption) on rumen volatile fatty acids (VFA) and gas production was studied with sheep rumen contents in vitro. 2. Some SFEs having monoester contents of more than 70% increased the molar proportion of propionate in conjunction with reduction in the acetate:propionate ratio when the individual SFE was added to rumen contents in a final concentration of 4 g/l. Laurate sugar ester was the most potent propionate enhancer and rumen gas depressor, the effective dose being as low as 1 g/l in a final concentration. Fatty acid esters other than SFEs had little, if any, effect on rumen VFA production and their molar proportions. 3. Approximately 50% of laurate sugar ester was hydrolysed by in vitro incubation with rumen fluid for 2 h. The addition of fatty acids and sucrose was also effective in the alterations of rumen VFA and gas production. However, the effect of SFEs on in vitro rumen fermentation was significantly greater than that of their constituent fatty acids or sucrose, or both. Accordingly, the effect appeared to be ascribed to the complex action of SFE itself and to its constituents, free fatty acids and sucrose. 4. SFEs, at the level of 4 g/l, reduced substantially the froth formation (ingesta volume increase) and seemed to be effective for the prevention of bloat.

Cocrystal Solubilization in Biorelevant Media and its Prediction from Drug Solubilization.

PubMed

Lipert, Maya P; Roy, Lilly; Childs, Scott L; Rodríguez-Hornedo, Naír

2015-12-01

This work examines cocrystal solubility in biorelevant media (FeSSIF, fed-state simulated intestinal fluid), and develops a theoretical framework that allows for the simple and quantitative prediction of cocrystal solubilization from drug solubilization. The solubilities of four hydrophobic drugs and seven cocrystals containing these drugs were measured in FeSSIF and in acetate buffer at pH 5.00. In all cases, the cocrystal solubility (Scocrystal ) was higher than the drug solubility (Sdrug ) in both buffer and FeSSIF; however, the solubilization ratio of drug, SRdrug = (SFeSSIF /Sbuffer )drug , was not the same as the solubilization ratio of cocrystal, SRcocrystal = (SFeSSIF /Sbuffer )cocrystal , meaning drug and cocrystal were not solubilized to the same extent in FeSSIF. This highlights the potential risk of anticipating cocrystal behavior in biorelevant media based on solubility studies in water. Predictions of SRcocrystal from simple equations based only on SRdrug were in excellent agreement with measured values. For 1:1 cocrystals, the cocrystal solubilization ratio (SR) can be obtained from the square root of the drug SR. For 2:1 cocrystals, SRcocrystal is found from (SRdrug )(2/3) . The findings in FeSSIF can be generalized to describe cocrystal behavior in other systems involving preferential solubilization of a drug such as surfactants, lipids, and other drug solubilizing media. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

Social Foundations of Education for the Information Age

ERIC Educational Resources Information Center

Waks, Leonard J.

2013-01-01

In this paper, Leonard J. Waks re-imagines the social foundations of education (SFE) as a project within the information society. He begins with what he believes to be a reasonably non-controversial definition: SFE is a field of scholarship and teaching aiming to provide a comprehensive understanding, through description, interpretation, and…

Space water electrolysis: Space Station through advance missions

NASA Technical Reports Server (NTRS)

Davenport, Ronald J.; Schubert, Franz H.; Grigger, David J.

1991-01-01

Static Feed Electrolyzer (SFE) technology can satisfy the need for oxygen (O2) and Hydrogen (H2) in the Space Station Freedom and future advanced missions. The efficiency with which the SFE technology can be used to generate O2 and H2 is one of its major advantages. In fact, the SFE is baselined for the Oxygen Generation Assembly within the Space Station Freedom's Environmental Control and Life Support System (ECLSS). In the conventional SFE process an alkaline electrolyte is contained within the matrix and is sandwiched between two porous electrodes. The electrodes and matrix make up a unitized cell core. The electrolyte provides the necessary path for the transport of water and ions between the electrodes, and forms a barrier to the diffusion of O2 and H2. A hydrophobic, microporous membrane permits water vapor to diffuse from the feed water to the cell core. This membrane separates the liquid feed water from the product H2, and, therefore, avoids direct contact of the electrodes by the feed water. The feed water is also circulated through an external heat exchanger to control the temperature of the cell.

Influence of an oxygen-inhibited layer on enamel bonding of dental adhesive systems: surface free-energy perspectives.

PubMed

Ueta, Hirofumi; Tsujimoto, Akimasa; Barkmeier, Wayne W; Oouchi, Hajime; Sai, Keiichi; Takamizawa, Toshiki; Latta, Mark A; Miyazaki, Masashi

2016-02-01

The influence of an oxygen-inhibited layer (OIL) on the shear bond strength (SBS) to enamel and surface free-energy (SFE) of adhesive systems was investigated. The adhesive systems tested were Scotchbond Multipurpose (SM), Clearfil SE Bond (CS), and Scotchbond Universal (SU). Resin composite was bonded to bovine enamel surfaces to determine the SBS, with and without an OIL, of adhesives. The SFE of cured adhesives with and without an OIL were determined by measuring the contact angles of three test liquids. There were no significant differences in the mean SBS of SM and CS specimens with or without an OIL; however, the mean SBS of SU specimens with an OIL was significantly higher than that of SU specimens without an OIL. For all three systems, the mean total SFE (γS), polarity force (γSp), and hydrogen bonding force (γSh) values of cured adhesives with an OIL were significantly higher than those of cured adhesives without an OIL. The results of this study indicate that the presence of an OIL promotes higher SBS of a single-step self-etch adhesive system, but not of a three-step or a two-step self-etch primer system. The SFE values of cured adhesives with an OIL were significantly higher than those without an OIL. The SFE characteristics of the OIL of adhesives differed depending on the type of adhesive. © 2015 Eur J Oral Sci.

Modeling UV Radiation Feedback from Massive Stars. II. Dispersal of Star-forming Giant Molecular Clouds by Photoionization and Radiation Pressure

NASA Astrophysics Data System (ADS)

Kim, Jeong-Gyu; Kim, Woong-Tae; Ostriker, Eve C.

2018-05-01

UV radiation feedback from young massive stars plays a key role in the evolution of giant molecular clouds (GMCs) by photoevaporating and ejecting the surrounding gas. We conduct a suite of radiation hydrodynamic simulations of star cluster formation in marginally bound, turbulent GMCs, focusing on the effects of photoionization and radiation pressure on regulating the net star formation efficiency (SFE) and cloud lifetime. We find that the net SFE depends primarily on the initial gas surface density, Σ0, such that the SFE increases from 4% to 51% as Σ0 increases from 13 to 1300 {M}ȯ {pc}}-2. Cloud destruction occurs within 2–10 Myr after the onset of radiation feedback, or within 0.6–4.1 freefall times (increasing with Σ0). Photoevaporation dominates the mass loss in massive, low surface density clouds, but because most photons are absorbed in an ionization-bounded Strömgren volume, the photoevaporated gas fraction is proportional to the square root of the SFE. The measured momentum injection due to thermal and radiation pressure forces is proportional to {{{Σ }}}0-0.74, and the ejection of neutrals substantially contributes to the disruption of low mass and/or high surface density clouds. We present semi-analytic models for cloud dispersal mediated by photoevaporation and by dynamical mass ejection, and show that the predicted net SFE and mass loss efficiencies are consistent with the results of our numerical simulations.

Effect of substrate roughness on the apparent surface free energy of sputter deposited superhydrophobic polytetrafluoroethylene coatings: A comparison of experimental data with different theoretical models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Selvakumar, N.; Barshilia, Harish C.; Rajam, K. S.

2010-07-15

We have studied the effect of substrate roughness on the wettability and the apparent surface free energy (SFE) of sputter deposited polytetrafluoroethylene (PTFE) coatings deposited on untreated glass (average roughness, R{sub a}=2.0 nm), plasma etched glass (R{sub a}=7.4 nm), and sandblasted glass (R{sub a}=4500 nm) substrates. The wettability of the PTFE coatings deposited on substrates with varying roughnesses was evaluated by measuring the apparent contact angle (CA) using a series of probe liquids from nonpolar aprotic to polar protic. The wettability measurements indicate that an apparent water CA of 152 deg. with a sliding angle of 8 deg. was achievedmore » for PTFE coatings deposited on a substrate with R{sub a}=4500 nm. The superhydrophobicity observed in these coatings is attributed to the presence of dual scale roughness, densely packed microstructure and the presence of CF{sub 3} groups. Unlike the bulk PTFE which is mainly dispersive, the sputter deposited PTFE coatings are expected to have some degree of polar component due to the plasma treatment. In order to calculate the dispersive SFE of PTFE coatings, we have used the Girifalco-Good-Fowkes (GGF) method and validated it with the Zisman model. Furthermore, the Owens-Wendt model has been used to calculate the dispersive and the polar components of the apparent SFE of the PTFE coatings. These results are further corroborated using the Fowkes method. Finally, an ''equation of state'' theory proposed by Neumann has been used to calculate the apparent SFE values of the PTFE coatings. The results indicate that the apparent SFE values of the PTFE coatings obtained from the Owens-Wendt and the Fowkes methods are comparable to those obtained from the Neumann's method. The analyses further demonstrate that the GGF and the Zisman methods underestimate the apparent SFE values of the sputter deposited PTFE coatings.« less

Evaluation of a novel, ultrathin, tip-bending endoscope in a synthetic force-sensing pancreas with comparison to medical guide wires

PubMed Central

Chandler, John E; Lee, Cameron M; Babchanik, Alexander P; Melville, C David; Saunders, Michael D; Seibel, Eric J

2012-01-01

Purpose Direct visualization of pancreatic ductal tissue is critical for early diagnosis of pancreatic diseases and for guiding therapeutic interventions. A novel, ultrathin (5 Fr) scanning fiber endoscope (SFE) with tip-bending capability has been developed specifically to achieve high resolution imaging as a pancreatoscope during endoscopic retrograde cholangiopancreatography (ERCP). This device has potential to dramatically improve both diagnostic and therapeutic capabilities during ERCP by providing direct video feedback and tool guidance to clinicians. Methods Invasiveness of the new tip-bending SFE was evaluated by a performance comparison to ERCP guide wires, which are routinely inserted into the pancreatic duct during ERCP. An in vitro test model with four force sensors embedded in a synthetic pancreas was designed to detect and compare the insertion forces for 0.89 mm and 0.53 mm diameter guide wires as well as the 1.7 mm diameter SFE. Insertions were performed through the working channel of a therapeutic duodenoscope for the two types of guide wires and using a statistically similar direct insertion method for comparison to the SFE. Results Analysis of the forces detected by the sensors showed the smaller diameter 0.53 mm wire produced significantly less average and maximum forces during insertion than the larger diameter 0.89 mm wire. With the use of tip-bending and optical visualization, the 1.7 mm diameter SFE produced significantly less average force during insertion than the 0.89 mm wire at every sensor, despite its larger size. It was further shown that the use of tip-bending with the SFE significantly reduced the forces at all sensors, compared to insertions when tip-bending was not used. Conclusion Combining high quality video imaging with two-axis tip-bending allows a larger diameter guide wire-style device to be inserted into the pancreatic duct during ERCP with improved capacity to perform diagnostics and therapy. PMID:23166452

Effect of reduced ferulate-mediated lignin/arabinoxylan cross-linking in corn silage on feed intake, digestibility, and milk production.

PubMed

Jung, H G; Mertens, D R; Phillips, R L

2011-10-01

Cross-linking of lignin to arabinoxylan by ferulates limits in vitro rumen digestibility of grass cell walls. The effect of ferulate cross-linking on dry matter intake (DMI), milk production, and in vivo digestibility was investigated in ad libitum and restricted-intake digestion trials with lambs, and in a dairy cow performance trial using the low-ferulate sfe corn mutant. Silages of 5 inbred corn lines were fed: W23, 2 W23sfe lines (M04-4 and M04-21), B73, and B73bm3. As expected, the W23sfe silages contained fewer ferulate ether cross-links and B73bm3 silage had a lower lignin concentration than the respective genetic controls. Silages were fed as the sole ingredient to 4 lambs per silage treatment. Lambs were confined to metabolism crates and fed ad libitum for a 12-d adaptation period followed by a 5-d collection period of feed refusals and feces. Immediately following the ad libitum feeding trial, silage offered was limited to 2% of body weight. After a 2-d adaptation to restricted feeding, feed refusals and feces were collected for 5 d. Seventy Holstein cows were blocked by lactation, days in milk, body weight, and milk production and assigned to total mixed ration diets based on the 5 corn silages. Diets were fed for 28 d and data were collected on weekly DMI and milk production and composition. Fecal grab samples were collected during the last week of the lactation trial for estimation of feed digestibility using acid-insoluble ash as a marker. Silage, total mixed ration, feed refusals, and fecal samples were analyzed for crude protein, starch, neutral detergent fiber (NDF), cell wall polysaccharides, and lignin. The W23sfe silages resulted in lower DMI in the ad libitum trial than the W23 silage, but DMI did not differ in the restricted trial. No differences were observed for NDF or cell wall polysaccharide digestibility by lambs with restricted feeding, but the amount of NDF digested daily increased for lambs fed the M04-21 W23sfe silage ad libitum. Lambs were less selective against NDF and lignin when offered W23sfe silages. The B73bm3 silage did not affect DMI or digestibility of cell walls at the restricted feeding level, but total daily NDF digested was greater at ad libitum intake. Intake, milk production, and cell wall digestibility were greater for cows fed diets containing W23sfe silages than for those fed W23 silage. Although milk production was greater for the B73bm3 diet, DMI and cell wall digestibility were not altered. Cows were less selective against cell wall material when fed both W23sfe and B73bm3 silages. Reduced ferulate cross-linking in sfe corn silage is a new genetic mechanism for improving milk production. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Carbon Nanotube Web with Carboxylated Polythiophene "Assist" for High-Performance Battery Electrodes.

PubMed

Kwon, Yo Han; Park, Jung Jin; Housel, Lisa M; Minnici, Krysten; Zhang, Guoyan; Lee, Sujin R; Lee, Seung Woo; Chen, Zhongming; Noda, Suguru; Takeuchi, Esther S; Takeuchi, Kenneth J; Marschilok, Amy C; Reichmanis, Elsa

2018-04-24

A carbon nanotube (CNT) web electrode comprising magnetite spheres and few-walled carbon nanotubes (FWNTs) linked by the carboxylated conjugated polymer, poly[3-(potassium-4-butanoate) thiophene] (PPBT), was designed to demonstrate benefits derived from the rational consideration of electron/ion transport coupled with the surface chemistry of the electrode materials components. To maximize transport properties, the approach introduces monodispersed spherical Fe 3 O 4 (sFe 3 O 4 ) for uniform Li + diffusion and a FWNT web electrode frame that affords characteristics of long-ranged electronic pathways and porous networks. The sFe 3 O 4 particles were used as a model high-capacity energy active material, owing to their well-defined chemistry with surface hydroxyl (-OH) functionalities that provide for facile detection of molecular interactions. PPBT, having a π-conjugated backbone and alkyl side chains substituted with carboxylate moieties, interacted with the FWNT π-electron-rich and hydroxylated sFe 3 O 4 surfaces, which enabled the formation of effective electrical bridges between the respective components, contributing to efficient electron transport and electrode stability. To further induce interactions between PPBT and the metal hydroxide surface, polyethylene glycol was coated onto the sFe 3 O 4 particles, allowing for facile materials dispersion and connectivity. Additionally, the introduction of carbon particles into the web electrode minimized sFe 3 O 4 aggregation and afforded more porous FWNT networks. As a consequence, the design of composite electrodes with rigorous consideration of specific molecular interactions induced by the surface chemistries favorably influenced electrochemical kinetics and electrode resistance, which afforded high-performance electrodes for battery applications.

Fluorescence image-guided photodynamic therapy of cancer cells using a scanning fiber endoscope

NASA Astrophysics Data System (ADS)

Woldetensae, Mikias H.; Kirshenbaum, Mark R.; Kramer, Greg M.; Zhang, Liang; Seibel, Eric J.

2013-03-01

A scanning fiber endoscope (SFE) and the cancer biomarker 5-aminolevulinic acid (5-ALA) were used to fluorescently detect and destroy superficial cancerous lesions, while experimenting with different dosimetry levels for concurrent or sequential imaging and laser therapy. The 1.6-mm diameter SFE was used to fluorescently image a confluent monolayer of A549 human lung cancer cells from culture, previously administered with 5 mM solution of 5-ALA for 4 hours. Twenty hours after therapy, cell cultures were stained to distinguish between living and dead cells using a laser scanning confocal microscope. To determine relative dosimetry for photodynamic therapy (PDT), 405-nm laser illumination was varied from 1 to 5 minutes with power varying from 5 to 18 mW, chosen to compare equal amounts of energy delivered to the cell culture. The SFE produced 500-line images of fluorescence at 15 Hz using the red detection channel centered at 635 nm. The results show that PDT of A549 cancer cell monolayers using 405nm light for imaging and 5-ALAinduced PpIX therapy was possible using the same SFE system. Increased duration and power of laser illumination produced an increased area of cell death upon live/dead staining. The ultrathin and flexible SFE was able to direct PDT using wide-field fluorescence imaging of a monolayer of cultured cancer cells after uptaking 5-ALA. The correlation between light intensity and duration of PDT was measured. Increased length of exposure and decreased light intensity yields larger areas of cell death than decreased length of exposure with increased light intensity.

Reversal of Fortune: Increased Star Formation Efficiencies in the Early Histories of Dwarf Galaxies?

NASA Astrophysics Data System (ADS)

Madau, Piero; Weisz, Daniel R.; Conroy, Charlie

2014-08-01

On dwarf galaxy scales, the different shapes of the galaxy stellar mass function and the dark halo mass function require a star-formation efficiency (SFE) in these systems that is currently more than 1 dex lower than that of Milky Way-size halos. Here, we argue that this trend may actually be reversed at high redshift. Specifically, by combining the resolved star-formation histories of nearby isolated dwarfs with the simulated mass-growth rates of dark matter halos, we show that the assembly of these systems occurs in two phases: (1) an early, fast halo accretion phase with a rapidly deepening potential well, characterized by a high SFE; and (2) a late, slow halo accretion phase where, perhaps as a consequence of reionization, the SFE is low. Nearby dwarfs have more old stars than predicted by assuming a constant or decreasing SFE with redshift, a behavior that appears to deviate qualitatively from the trends seen among more massive systems. Taken at face value, the data suggest that at sufficiently early epochs, dwarf galaxy halos above the atomic cooling mass limit can be among the most efficient sites of star formation in the universe.

An evolutionary model for collapsing molecular clouds and their star formation activity. II. Mass dependence of the star formation rate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zamora-Avilés, Manuel; Vázquez-Semadeni, Enrique

We discuss the evolution and dependence on cloud mass of the star formation rate (SFR) and efficiency (SFE) of star-forming molecular clouds (MCs) within the scenario that clouds are undergoing global collapse and that the SFR is controlled by ionization feedback. We find that low-mass clouds (M {sub max} ≲ 10{sup 4} M {sub ☉}) spend most of their evolution at low SFRs, but end their lives with a mini-burst, reaching a peak SFR ∼10{sup 4} M {sub ☉} Myr{sup –1}, although their time-averaged SFR is only (SFR) ∼ 10{sup 2} M {sub ☉} Myr{sup –1}. The corresponding efficiencies aremore » SFE{sub final} ≲ 60% and (SFE) ≲ 1%. For more massive clouds (M {sub max} ≳ 10{sup 5} M {sub ☉}), the SFR first increases and then reaches a plateau because the clouds are influenced by stellar feedback since earlier in their evolution. As a function of cloud mass, (SFR) and (SFE) are well represented by the fits (SFR) ≈ 100(1 + M {sub max}/1.4 × 10{sup 5} M {sub ☉}){sup 1.68} M {sub ☉} Myr{sup –1} and (SFE) ≈ 0.03(M {sub max}/2.5 × 10{sup 5} M {sub ☉}){sup 0.33}, respectively. Moreover, the SFR of our model clouds follows closely the SFR-dense gas mass relation recently found by Lada et al. during the epoch when their instantaneous SFEs are comparable to those of the clouds considered by those authors. Collectively, a Monte Carlo integration of the model-predicted SFR(M) over a Galactic giant molecular cloud mass spectrum yields values for the total Galactic SFR that are within half an order of magnitude of the relation obtained by Gao and Solomon. Our results support the scenario that star-forming MCs may be in global gravitational collapse and that the low observed values of the SFR and SFE are a result of the interruption of each SF episode, caused primarily by the ionizing feedback from massive stars.« less

Oxidative Remobilization of Technetium Sequestered by Sulfide-Transformed Nano Zerovalent Iron

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fan, Dimin; Anitori, Roberto; Tebo, Bradley M.

2014-06-02

The dissolution of Tc(IV) sulfide and concurrent transformation of sulfidated ZVI during 2 oxidation were examined. Kinetic data obtained with 10 mL batch reactors showed that Tc(VII) 3 reduced by sulfidated nZVI has significantly slower reoxidation rates than Tc(VII) reduced by 4 nZVI only. In a 50 mL batch reactor, initial inhibition of Tc(IV) dissolution was apparent and 5 lasted until 120 hours at S/Fe = 0.112, presumably due to the redox buffer capacity of FeS. This 6 is evidenced by the parallel trends in oxidation-reduction potentials (ORP) and Tc dissolution 7 kinetics. Mӧssbauer spectra and micro X-ray diffraction ofmore » S/Fe = 0.112 suggested the 8 persistence of FeS after 24-h oxidation although X-ray photoelectron spectroscopy indicated 9 substantial surface oxidation. After 120-h oxidation, all characterizations showed complete 10 oxidation of FeS, which further indicates that FeS inhibits Tc oxidation. X-ray absorption 11 spectroscopy for S/Fe = 0.011 showed significantly increasing percentage of TcS2 in the solid 12 phase after 24-h oxidation, indicating TcS2 is more resistant to oxidation than TcO2. At S/Fe = 13 0.112, the XAS results revealed significant transformation of Tc speciation from TcS2 to TcO2 14 after 120-h oxidation at S/Fe = 0.112. Given that no apparent Tc dissolution occurred during this 15 period, the speciation transformation might play a secondary role in hindering Tc oxidation, 16 especially as redox buffer capacity approached depletion.« less

SDSS-IV MaNGA-resolved Star Formation and Molecular Gas Properties of Green Valley Galaxies: A First Look with ALMA and MaNGA

NASA Astrophysics Data System (ADS)

Lin, Lihwai; Belfiore, Francesco; Pan, Hsi-An; Bothwell, M. S.; Hsieh, Pei-Ying; Huang, Shan; Xiao, Ting; Sánchez, Sebastián F.; Hsieh, Bau-Ching; Masters, Karen; Ramya, S.; Lin, Jing-Hua; Hsu, Chin-Hao; Li, Cheng; Maiolino, Roberto; Bundy, Kevin; Bizyaev, Dmitry; Drory, Niv; Ibarra-Medel, Héctor; Lacerna, Ivan; Haines, Tim; Smethurst, Rebecca; Stark, David V.; Thomas, Daniel

2017-12-01

We study the role of cold gas in quenching star formation in the green valley by analyzing ALMA 12CO (1-0) observations of three galaxies with resolved optical spectroscopy from the MaNGA survey. We present resolution-matched maps of the star formation rate and molecular gas mass. These data are used to calculate the star formation efficiency (SFE) and gas fraction ({f}{gas}) for these galaxies separately in the central “bulge” regions and outer disks. We find that, for the two galaxies whose global specific star formation rate (sSFR) deviates most from the star formation main sequence, the gas fraction in the bulges is significantly lower than that in their disks, supporting an “inside-out” model of galaxy quenching. For the two galaxies where SFE can be reliably determined in the central regions, the bulges and disks share similar SFEs. This suggests that a decline in {f}{gas} is the main driver of lowered sSFR in bulges compared to disks in green valley galaxies. Within the disks, there exist common correlations between the sSFR and SFE and between sSFR and {f}{gas} on kiloparsec scales—the local SFE or {f}{gas} in the disks declines with local sSFR. Our results support a picture in which the sSFR in bulges is primarily controlled by {f}{gas}, whereas both SFE and {f}{gas} play a role in lowering the sSFR in disks. A larger sample is required to confirm if the trend established in this work is representative of the green valley as a whole.

The effect of photoionizing feedback on star formation in isolated and colliding clouds

NASA Astrophysics Data System (ADS)

Shima, Kazuhiro; Tasker, Elizabeth J.; Federrath, Christoph; Habe, Asao

2018-05-01

We investigate star formation occurring in idealized giant molecular clouds, comparing structures that evolve in isolation versus those undergoing a collision. Two different collision speeds are investigated and the impact of photoionizing radiation from the stars is determined. We find that a colliding system leads to more massive star formation both with and without the addition of feedback, raising overall star formation efficiencies (SFE) by a factor of 10 and steepening the high-mass end of the stellar mass function. This rise in SFE is due to increased turbulent compression during the cloud collision. While feedback can both promote and hinder star formation in an isolated system, it increases the SFE by approximately 1.5 times in the colliding case when the thermal speed of the resulting H II regions matches the shock propagation speed in the collision.

Surface free energy analysis of oil palm empty fruit bunches fiber reinforced biocomposites

NASA Astrophysics Data System (ADS)

Suryadi, G. S.; Nikmatin, S.; Sudaryanto; Irmansyah; Sukaryo, S. G.

2017-05-01

Study of the size effect of natural fiber from oil palm empty fruit bunches (OPEFB) as filler, onto the contact angle and surface free energy of fiber reinforced biocomposites has been done. The OPEFB fibers were prepared by mechanical milling and sieving to obtain various sizes of fiber (long-fiber, medium-fiber, short-fiber, and microparticle). The biocomposites has been produced by extrusion using single-screw extruder with EFB fiber as filler, recycled Acrylonitrile Butadiene Styrene (ABS) polymer as matrix, and primary antioxidant, acid scavanger, and coupling agent as additives. The obtained biocomposites in form of granular, were made into test piece by injection molding method. Contact angles of water, methanol, and hexane on the surface of biocomposites at room temperature were measured using Phoenix 300 Contact Angle Analyzer. The surface free energy (SFE) and their components were calculated using three previous known methods (Girifalco-Good-Fowkes-Young (GGFY), Owens-Wendt, and van Oss-Chaudhury-Good (vOCG)). The results showed that total SFE of Recycled ABS as control was about 24.38 mJ/m2, and SFE of biocomposites was lower than control, decreased with decreasing of EFB fiber size as biocomposites filler. The statistical analysis proved that there are no statistically significant differences in the value of the SFE calculated with the three different methods.

Wavelet-based spectral finite element dynamic analysis for an axially moving Timoshenko beam

NASA Astrophysics Data System (ADS)

Mokhtari, Ali; Mirdamadi, Hamid Reza; Ghayour, Mostafa

2017-08-01

In this article, wavelet-based spectral finite element (WSFE) model is formulated for time domain and wave domain dynamic analysis of an axially moving Timoshenko beam subjected to axial pretension. The formulation is similar to conventional FFT-based spectral finite element (SFE) model except that Daubechies wavelet basis functions are used for temporal discretization of the governing partial differential equations into a set of ordinary differential equations. The localized nature of Daubechies wavelet basis functions helps to rule out problems of SFE model due to periodicity assumption, especially during inverse Fourier transformation and back to time domain. The high accuracy of WSFE model is then evaluated by comparing its results with those of conventional finite element and SFE results. The effects of moving beam speed and axial tensile force on vibration and wave characteristics, and static and dynamic stabilities of moving beam are investigated.

Stacking fault energies of face-centered cubic concentrated solid solution alloys

DOE PAGES

Zhao, Shijun; Stocks, G. Malcolm; Zhang, Yanwen

2017-06-22

We report the stacking fault energy (SFE) for a series of face-centered cubic (fcc) equiatomic concentrated solid solution alloys (CSAs) derived as subsystems from the NiCoFeCrMn and NiCoFeCrPd high entropy alloys based on ab initio calculations. At low temperatures, these CSAs display very low even negative SFEs, indicating that hexagonal close-pack ( hcp) is more energy favorable than fcc structure. The temperature dependence of SFE for some CSAs is studied. With increasing temperature, a hcp-to- fcc transition is revealed for those CSAs with negative SFEs, which can be attributed to the role of intrinsic vibrational entropy. The analysis of themore » vibrational modes suggests that the vibrational entropy arises from the high frequency states in the hcp structure that originate from local vibrational mode. Furthermore, our results underscore the importance of vibrational entropy in determining the temperature dependence of SFE for CSAs.« less

Stacking fault energies of face-centered cubic concentrated solid solution alloys

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Shijun; Stocks, G. Malcolm; Zhang, Yanwen

We report the stacking fault energy (SFE) for a series of face-centered cubic (fcc) equiatomic concentrated solid solution alloys (CSAs) derived as subsystems from the NiCoFeCrMn and NiCoFeCrPd high entropy alloys based on ab initio calculations. At low temperatures, these CSAs display very low even negative SFEs, indicating that hexagonal close-pack ( hcp) is more energy favorable than fcc structure. The temperature dependence of SFE for some CSAs is studied. With increasing temperature, a hcp-to- fcc transition is revealed for those CSAs with negative SFEs, which can be attributed to the role of intrinsic vibrational entropy. The analysis of themore » vibrational modes suggests that the vibrational entropy arises from the high frequency states in the hcp structure that originate from local vibrational mode. Furthermore, our results underscore the importance of vibrational entropy in determining the temperature dependence of SFE for CSAs.« less

The comparison of anti-oxidative kinetics in vitro of the fluid extract from maidenhair tree, motherwort and hawthorn.

PubMed

Bernatoniene, Jurga; Kucinskaite, Agne; Masteikova, Ruta; Kalveniene, Zenona; Kasparaviciene, Giedre; Savickas, Arunas

2009-01-01

The aim of the study was to perform a quantitative analysis of fluid extracts of maidenhair tree (Ginkgo biloba L.), motherwort (Leonurus cardiaca L.) and hawthorn (Crataegus monogyna Jacq.), to evaluate their antioxidant activity and to compare their ability to inactivate free radicals. The antioxidant activity was measured using the DPPH*and the ABTS*+ radical scavenging reaction systems. The study showed that the manifestation of the radical scavenging capacity in the DPPH* reaction system was in the following order: the fluid extract of hawthorn (70.37 +/- 0.80%) > the fluid extract of maidenhair tree (82.63 +/- 0.23%) > the fluid extract of motherwort (84.89 +/- 0.18%), while in the ABTS*+ reaction system, the manifestation of the radical scavenging capacity was in the following order: the fluid extract of hawthorn (87.09 +/- 0.55%) > the fluid extract of motherwort (88.28 +/- 1.06%) > the fluid extract of maidenhair tree (88.39 +/- 0.72%). The results showed that in the DPPH* reaction system, fluid extract of motherwort manifested higher antioxidant activity, compared to the fluid extracts of maidenhair tree and hawthorn. By contrast, in the ABTS*+ reaction system, higher antioxidant activity was found in the fluid extract of maidenhair tree, compared to the fluid extracts of motherwort and hawthorn. This would suggest that preparations manufactured from these herbal raw materials could be used as effective preventive means and valuable additional remedies in the treatment of diseases caused by oxidative stress.

Aromatic moieties in meteoritic macromolecular materials: analyses by hydrous pyrolysis and δ 13C of individual compounds

NASA Astrophysics Data System (ADS)

Sephton, M. A.; Pillinger, C. T.; Gilmour, I.

2000-01-01

Hydrous pyrolysis, supercritical fluid extraction (SFE), gas chromatography-mass-spectrometry (GC-MS) and isotope ratio monitoring-gas chromatography-mass spectrometry (irm-GC-MS) were used to investigate the constitution of macromolecular materials in meteorites. Results from the carbonaceous chondrites Orgueil (CI1) and Cold Bokkeveld (CM2) were compared with those obtained previously from Murchison (CM2). Fragments of meteoritic macromolecular materials were produced by hydrous pyrolysis, extracted by SFE, and identified by GC-MS. The CI1 and CM2 hydrous pyrolysates all contain volatile aromatic compounds, some of which have aliphatic side chains, hydroxyl groups, and thiophene rings attached. The results indicate that the macromolecular materials in these meteorites are qualitatively similar. However, the pyrolysates show significant quantitative differences, with the products of ether linkages and condensed aromatic networks being less abundant in the more aqueously altered meteorites. In addition, the methylnaphthalene maturity parameter negatively correlates with aqueous alteration. These features are interpreted as the result of chemical reactions favored under hydrous conditions. Hence, the extent of aqueous alteration on the meteorite parent body appears to be the most important evolutionary stage in determining the final structure of macromolecular materials in the CI1 and CM2 meteorites. The carbon isotopic compositions of the fragments of macromolecular materials were determined by irm-GC-MS. δ 13C values for the hydrous pyrolysis products range from -25.5 to -10.2‰ for Orgueil and -22.9 to +4.0‰ for Cold Bokkeveld. These values can be compared to the -24.6 to -5.6‰ range obtained previously for Murchison. The low molecular weight components in each hydrous pyrolysate display shifts to increased 13C contents with carbon number. This indicates the production of simple organic entities by the preferential cracking of 12C- 12C bonds in more complex starting materials. The shifts extend from C 7 to C 8 for Orgueil and Cold Bokkeveld but from C 7 to C 10 for Murchison. Higher molecular weight components for all of the hydrous pyrolysates show a general trend of decreasing 13C content with carbon number. The higher molecular weight features can be explained by the preferential addition of 12C during the primary synthesis of the macromolecular materials. In addition, δ 13C values for the methylnaphthalenes are consistent with the addition of 12C to the most reactive site on the naphthalene parent molecule providing supporting evidence for synthesis. Hence, the macromolecular materials are composed of organic units created by both synthesis and cracking. Therefore, secondary processing by liquid water on the meteorite parent body exerts a strong control on the final molecular architecture of meteoritic macromolecular materials. Yet, the carbon isotopic compositions of some individual moieties may retain a record of primary synthesis.

Surface properties of polyetheretherketone after different laboratory and chairside polishing protocols.

PubMed

Heimer, Sina; Schmidlin, Patrick R; Roos, Malgorzata; Stawarczyk, Bogna

2017-03-01

Polyetheretherketone (PEEK) can be used as a framework material for fixed dental prostheses. However, information about laboratory and chairside polishing methods is still scarce. The purpose of this in vitro study was to determine the effects of laboratory and chairside polishing methods on the surface roughness (SR) and surface free energy (SFE) of PEEK, an autopolymerizing poly(methyl methacrylate), and a veneering composite resin. For each of the 3 materials, 80 specimens were prepared (N=240) and divided into 7 polishing groups and 1 control group (n=10). The 7 groups were split into 4 laboratory protocols: polishing paste (Abraso), a second polishing paste (Opal L), silicone polisher (Ceragum), and diamond grinder (Diagen-Turbo grinder). The other 3 groups were chairside protocols: rainbow technique (Super-Snap kit), polishing paste (Prisma gloss), and a polishing system (Enhance finishing). Machine polishing with SiC P4000 served as the control treatment. The protocols' average SRs and SFEs were measured, and their surface topographies were evaluated with scanning electron microscopy (SEM). The logarithmically transformed data were analyzed using covariance analysis, 2-way and 1-way ANOVA, and partial correlation (α=.05). The polishing protocol exerted the highest influence on SR and SFE values (P<.001; SR: partial eta squared η P 2 =.970; SFE: η P 2 =.450), followed by material group (P<.001, SR: η P 2 =.319; SFE: η P 2 =.429). The interaction effect of the binary combinations of the 2 independent parameters (polishing protocol and material group) was also significant (P<.001, SR: η P 2 =.681; SFE: η P 2 =.365). Chairside methods presented lower SR values than laboratory methods, and specimens polished using the 2-body mode showed higher SR than did specimens polished using the 3-body mode. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Supercritical Fluid Fractionation of JP-8

DTIC Science & Technology

1991-12-26

applications, such as coffee decaffeination , spice extraction, and lipids purification. The processing principles have also long been well known and ipracticed...PRINCIPLES OF SUPERCRITICAL FLUID EXTRACTION 8 A. Background on Supercritical Fluid Solubility 8 B. Supercritical Fluid Extraction Process ...Operation I0 1. Batch Extraction of Solid Materials 10 2. Counter-Current Continuous SCF Processing of Liquid 15 Products 3. Supercritical Fluid Extraction vs

Multimodal flexible cystoscopy for creating co-registered panoramas of the bladder urothelium

NASA Astrophysics Data System (ADS)

Seibel, Eric J.; Soper, Timothy D.; Burkhardt, Matthew R.; Porter, Michael P.; Yoon, W. Jong

2012-02-01

Bladder cancer is the most expensive cancer to treat due to the high rate of recurrence. Though white light cystoscopy is the gold standard for bladder cancer surveillance, the advent of fluorescence biomarkers provides an opportunity to improve sensitivity for early detection and reduced recurrence resulting from more accurate excision. Ideally, fluorescence information could be combined with standard reflectance images to provide multimodal views of the bladder wall. The scanning fiber endoscope (SFE) of 1.2mm in diameter is able to acquire wide-field multimodal video from a bladder phantom with fluorescence cancer "hot-spots". The SFE generates images by scanning red, green, and blue (RGB) laser light and detects the backscatter signal for reflectance video of 500-line resolution at 30 frames per second. We imaged a bladder phantom with painted vessels and mimicked fluorescent lesions by applying green fluorescent microspheres to the surface. By eliminating the green laser illumination, simultaneous reflectance and fluorescence images can be acquired at the same field of view, resolution, and frame rate. Moreover, the multimodal SFE is combined with a robotic steering mechanism and image stitching software as part of a fully automated bladder surveillance system. Using this system, the SFE can be reliably articulated over the entire 360° bladder surface. Acquired images can then be stitched into a multimodal 3D panorama of the bladder using software developed in our laboratory. In each panorama, the fluorescence images are exactly co-registered with RGB reflectance.

Effect of outflow on spring and summertime distribution and abundance of larval and juvenile fishes in the upper San Francisco Estuary

USGS Publications Warehouse

Dege, M.; Brown, L.R.

2004-01-01

We analyzed data on spring and summertime larval and juvenile fish distribution and abundance in the upper San Francisco Estuary (SFE), California between 1995 and 2001. The upper SFE includes the tidal freshwater areas of the Sacramento-San Joaquin Delta downstream to the euryhaline environment of San Pablo Bay. The sampling period included years with a variety of outflow conditions. Fifty taxa were collected using a larval tow net. Two common native species, delta smelt Hypomesus transpacifucus and longfin smelt Spirinchus thaleichthys, and four common alien taxa, striped bass Morone saxatilis, threadfin shad Dorosoma petenense, gobies of the genus Tridentiger, and yellowfin goby Acanthogobins flavimanus, were selected for detailed analysis. Outflow conditions had a strong influence on the geographic distribution of most of the species, but distribution with respect to the 2 psu isohaline (X2) was not affected. The distribution patterns of delta smelt, longfin smelt, and striped bass were consistent with larvae moving from upstream freshwater spawning areas to down-stream estuarine rearing areas. There were no obvious relationships of outflow with annual abundance indices. Our results support the idea of using X2 as an organizing principle in understanding the ecology of larval fishes in the upper SFE. Additional years of sampling will likely lead to additional insights into the early life history of upper SFE fishes. ?? Copyright by the American Fisheries Society 2004.

Antioxidant and Antilipid Peroxidation Potential of Supercritical Fluid Extract and Ethanol Extract of Leaves of Vitex Negundo Linn.

PubMed Central

Nagarsekar, K. S.; Nagarsenker, M. S.; Kulkarni, S. R.

2011-01-01

Supercritical fluid extract and ethanol extract of Vitex negundo Linn. were subjected to the chromatographic evaluation for identification of their constituents. Free radical scavenging activity of both extracts was studied by subjecting them to DPPH assay. IC50 values of ethanol and supercritical fluid extract of Vitex negundo indicate that ethanol extract has stronger reducing potential and ability to scavenge free radicals as compared to the supercritical fluid extract. The in vivo effect of extracts on lipid peroxidation was studied using ethanol induced oxidative stress model in rat. Ingestion of extracts for 14 days exhibited significant reduction in plasma MDA level of stressed animals. Ethanol extract exhibited higher in vivo antilipid peroxidation potential as compared to supercritical fluid extract which correlated well with radical scavenging potential of extract. PMID:22707827

On-line coupling of supercritical fluid extraction and chromatographic techniques.

PubMed

Sánchez-Camargo, Andrea Del Pilar; Parada-Alfonso, Fabián; Ibáñez, Elena; Cifuentes, Alejandro

2017-01-01

This review summarizes and discusses recent advances and applications of on-line supercritical fluid extraction coupled to liquid chromatography, gas chromatography, and supercritical fluid chromatographic techniques. Supercritical fluids, due to their exceptional physical properties, provide unique opportunities not only during the extraction step but also in the separation process. Although supercritical fluid extraction is especially suitable for recovery of non-polar organic compounds, this technique can also be successfully applied to the extraction of polar analytes by the aid of modifiers. Supercritical fluid extraction process can be performed following "off-line" or "on-line" approaches and their main features are contrasted herein. Besides, the parameters affecting the supercritical fluid extraction process are explained and a "decision tree" is for the first time presented in this review work as a guide tool for method development. The general principles (instrumental and methodological) of the different on-line couplings of supercritical fluid extraction with chromatographic techniques are described. Advantages and shortcomings of supercritical fluid extraction as hyphenated technique are discussed. Besides, an update of the most recent applications (from 2005 up to now) of the mentioned couplings is also presented in this review. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ancient fish and recent invaders: white sturgeon Acipenser transmontanus diet response to invasive-species-mediated changes in a benthic prey assemblage

USGS Publications Warehouse

Zeug, Steven C; Brodsky, Annie; Kogut, Nina; Stewart, Robin; Merz, Joe

2014-01-01

Invasive organisms can have significant impacts on native species, and the San Francisco Estuary (SFE), California, USA, is one of the world's most invaded estuaries. Decline of native white sturgeon Acipenser transmontanus abundance in the SFE has been acknowledged, but underlying mechanisms are poorly understood. Invasion by the overbite clam Potamocorbula amurensis has drastically altered the SFE benthic prey community, yet little is known about how this change has affected sturgeon diets. We investigated changes in the diet of white sturgeon following the overbite clam invasion and subsequent shift in the SFE benthic prey assemblage. Gut content analysis was used to compare white sturgeon prey composition and importance between the pre- and post-invasion periods. Additionally, stable isotope analysis was employed to estimate the assimilation of prey items to sturgeon biomass. Overbite clams dominated diets in the post-invasion period, accounting for 82 to 93% of total volume. Stable isotope analysis confirmed the importance of this prey item, although their assimilated contribution to sturgeon biomass was estimated to be less (70 to 83%) than gut contents indicated. The frequency of fish in white sturgeon guts increased in the post-invasion period, and isotope analysis indicated relatively large contributions of fish to sturgeon biomass (3.7 to 19%). The trophic adaptability of white sturgeon has allowed them to exploit this new prey source (overbite clam). Future conservation and restoration efforts must consider a potentially destabilized food web given the large importance of a single prey item.

Laser induced fluorescence as a diagnostic tool integrated into a scanning fiber endoscope for mouse imaging

NASA Astrophysics Data System (ADS)

Brown, Christopher M.; Maggio-Price, Lillian; Seibel, Eric J.

2007-02-01

Scanning fiber endoscope (SFE) technology has shown promise as a minimally invasive optical imaging tool. To date, it is capable of capturing full-color 500-line images, at 15 Hz frame rate in vivo, as a 1.6 mm diameter endoscope. The SFE uses a singlemode optical fiber actuated at mechanical resonance to scan a light spot over tissue while backscattered or fluorescent light at each pixel is detected in time series using several multimode optical fibers. We are extending the capability of the SFE from a RGB reflectance imaging device to a diagnostic tool by imaging laser induced fluorescence (LIF) in tissue, allowing for correlation of endogenous fluorescence to tissue state. Design of the SFE for diagnostic imaging is guided by a comparison of single point spectra acquired from an inflammatory bowel disease (IBD) model to tissue histology evaluated by a pathologist. LIF spectra were acquired by illuminating tissue with a 405 nm light source and detecting intrinsic fluorescence with a multimode optical fiber. The IBD model used in this study was mdr1a-/- mice, where IBD was modulated by infection with Helicobacter bilis. IBD lesions in the mouse model ranged from mild to marked hyperplasia and dysplasia, from the distal colon to the cecum. A principle components analysis (PCA) was conducted on single point spectra of control and IBD tissue. PCA allowed for differentiation between healthy and dysplastic tissue, indicating that emission wavelengths from 620 - 650 nm were best able to differentiate diseased tissue and inflammation from normal healthy tissue.

Interplay of oxygen-evolution kinetics and photovoltaic power curves on the construction of artificial leaves

PubMed Central

Surendranath, Yogesh; Bediako, D. Kwabena; Nocera, Daniel G.

2012-01-01

An artificial leaf can perform direct solar-to-fuels conversion. The construction of an efficient artificial leaf or other photovoltaic (PV)-photoelectrochemical device requires that the power curve of the PV material and load curve of water splitting, composed of the catalyst Tafel behavior and cell resistances, be well-matched near the thermodynamic potential for water splitting. For such a condition, we show here that the current density-voltage characteristic of the catalyst is a key determinant of the solar-to-fuels efficiency (SFE). Oxidic Co and Ni borate (Co-Bi and Ni-Bi) thin films electrodeposited from solution yield oxygen-evolving catalysts with Tafel slopes of 52 mV/decade and 30 mV/decade, respectively. The consequence of the disparate Tafel behavior on the SFE is modeled using the idealized behavior of a triple-junction Si PV cell. For PV cells exhibiting similar solar power-conversion efficiencies, those displaying low open circuit voltages are better matched to catalysts with low Tafel slopes and high exchange current densities. In contrast, PV cells possessing high open circuit voltages are largely insensitive to the catalyst’s current density-voltage characteristics but sacrifice overall SFE because of less efficient utilization of the solar spectrum. The analysis presented herein highlights the importance of matching the electrochemical load of water-splitting to the onset of maximum current of the PV component, drawing a clear link between the kinetic profile of the water-splitting catalyst and the SFE efficiency of devices such as the artificial leaf. PMID:22689962

The mechanism of deterioration of the glucosinolate-myrosynase system in radish roots during cold storage after harvest.

PubMed

Lee, Jeong Gu; Lim, Sooyeon; Kim, Jongkee; Lee, Eun Jin

2017-10-15

The hydrolysis of glucosinolates (GSLs) by myrosinase yields varieties of degradation products including isothiocyanates (ITCs). This process is controlled by the glucosinolate-myrosinase (G-M) system. The major ITCs in radish roots are raphasatin and sulforaphene (SFE), and the levels of these compounds decrease during storage after harvest. We investigated the G-M system to understand the mechanism behind the decrease in the ITCs in radish roots. Six varieties of radish roots were stored for 8weeks at 0-1.5°C. The concentrations of GSLs (glucoraphasatin and glucoraphenin) were maintained at harvest levels without significant changes during the storage period. However, SFE concentration and myrosinase activity remarkably decreased for 8weeks. Pearson correlation analysis between ITCs, GSLs, and myrosinase activity showed that a decrease of SFE during storage had a positive correlation with a decrease in myrosinase activity, which resulted from a decrease of ascorbic acid but also a decrease of myrosinase activity-related gene expressions. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Dispersal of Giant Molecular Clouds by Photoionization and Radiation Pressure

NASA Astrophysics Data System (ADS)

Kim, Jeong-Gyu; Kim, Woong-Tae; Ostriker, Eve C.

2018-01-01

UV radiation feedback from young massive stars plays a key role in the evolution of giant molecular clouds (GMCs) by forming HII regions and driving their expansion. We present the results of radiation hydrodynamic simulations of star cluster formation in turbulent GMCs, focusing on the effects of photoionization and radiation pressure on regulating the net star formation efficiency (SFE) and lifetime of clouds. We find that the net SFE depends primarily on the initial gas surface density, $\\Sigma_0$, such that the net SFE increases from 4% to 50% as $\\Sigma_0$ increases from $20\\,M_{\\odot}\\,{\\rm pc}^{-2}$ to $1300\\,M_{\\odot}\\,{\\rm pc}^{-2}$. Cloud dispersal occurs within $10\\,{\\rm Myr}$ after the onset of radiation feedback, or within 0.7--4.0 free-fall times that increases with $\\Sigma_0$. Photoionization plays a dominant role in destroying molecular clouds typical of the Milky Way, while radiation pressure takes over in massive, dense clouds. Based on the analysis of mass loss processes by photoevaporation or momentum injection, we develop a semi-analytic model for cloud dispersal and compare it with the numerical results.

Significant contribution of stacking faults to the strain hardening behavior of Cu-15%Al alloy with different grain sizes.

PubMed

Tian, Y Z; Zhao, L J; Chen, S; Shibata, A; Zhang, Z F; Tsuji, N

2015-11-19

It is commonly accepted that twinning can induce an increase of strain-hardening rate during the tensile process of face-centered cubic (FCC) metals and alloys with low stacking fault energy (SFE). In this study, we explored the grain size effect on the strain-hardening behavior of a Cu-15 at.%Al alloy with low SFE. Instead of twinning, we detected a significant contribution of stacking faults (SFs) irrespective of the grain size even in the initial stage of tensile process. In contrast, twinning was more sensitive to the grain size, and the onset of deformation twins might be postponed to a higher strain with increasing the grain size. In the Cu-15 at.%Al alloy with a mean grain size of 47 μm, there was a stage where the strain-hardening rate increases with strain, and this was mainly induced by the SFs instead of twinning. Thus in parallel with the TWIP effect, we proposed that SFs also contribute significantly to the plasticity of FCC alloys with low SFE.

Significant contribution of stacking faults to the strain hardening behavior of Cu-15%Al alloy with different grain sizes

PubMed Central

Tian, Y. Z.; Zhao, L. J.; Chen, S.; Shibata, A.; Zhang, Z. F.; Tsuji, N.

2015-01-01

It is commonly accepted that twinning can induce an increase of strain-hardening rate during the tensile process of face-centered cubic (FCC) metals and alloys with low stacking fault energy (SFE). In this study, we explored the grain size effect on the strain-hardening behavior of a Cu-15 at.%Al alloy with low SFE. Instead of twinning, we detected a significant contribution of stacking faults (SFs) irrespective of the grain size even in the initial stage of tensile process. In contrast, twinning was more sensitive to the grain size, and the onset of deformation twins might be postponed to a higher strain with increasing the grain size. In the Cu-15 at.%Al alloy with a mean grain size of 47 μm, there was a stage where the strain-hardening rate increases with strain, and this was mainly induced by the SFs instead of twinning. Thus in parallel with the TWIP effect, we proposed that SFs also contribute significantly to the plasticity of FCC alloys with low SFE. PMID:26582568

Chemical composition and bioactivity of Citrus medica L. cv. Diamante essential oil obtained by hydrodistillation, cold-pressing and supercritical carbon dioxide extraction.

PubMed

Menichini, Federica; Tundis, Rosa; Bonesi, Marco; de Cindio, Bruno; Loizzo, Monica R; Conforti, Filomena; Statti, Giancarlo A; Menabeni, Roberta; Bettini, Ruggero; Menichini, Francesco

2011-04-01

The chemical composition of the essential oil of Citrus medica L. cv. Diamante peel obtained by hydrodistillation, cold-pressing and supercritical carbon dioxide extraction techniques was determined by GC/MS analysis. Forty-six components were fully characterised. Limonene and γ-terpinene were the major components of the oils obtained by hydrodistillation (HD) and cold-pressing (CP), while citropten was the major constituent in the oil obtained by supercritical carbon dioxide extraction (SFE). Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities were evaluated. The essential oil obtained by hydrodistillation exerted the highest inhibitory activity against BChE (IC₅₀ value of 154.6 µg mL⁻¹) and AChE (IC₅₀ value of 171.3 µg mL⁻¹. Interestingly, the oil obtained by cold-pressing exhibited a selective inhibitory activity against AChE. The essential oils have also been evaluated for the inhibition of NO production in LPS induced RAW 264.7 macrophages. The oil obtained by hydrodistillation exerted a significant inhibition of NO production with an IC₅₀ value of 17 µg mL⁻¹ (IC₅₀ of positive control 53 µg mL⁻¹).

Gas-Phase Combustion Synthesis of Nonoxide Nanoparticles in Microgravity

NASA Technical Reports Server (NTRS)

Axelbaum, R. L.; Kumfer, B. M.; Sun, Z.; Chao, B. H.

2001-01-01

Gas-phase combustion synthesis is a promising process for creating nanoparticles for the growing nanostructure materials industry. The challenges that must be addressed are controlling particle size, preventing hard agglomerates, maintaining purity, and, if nonoxides are synthesized, protecting the particles from oxidation and/or hydrolysis during post-processing. Sodium-halide Flame Encapsulation (SFE) is a unique methodology for producing nonoxide nanoparticles that addresses these challenges. This flame synthesis process incorporates sodium and metal-halide chemistry, resulting in nanoparticles that are encapsulated in salt during the early stages of their growth in the flame. Salt encapsulation has been shown to allow control of particle size and morphology, while serving as an effective protective coating for preserving the purity of the core particles. Metals and compounds that have been produced using this technology include Al, W, Ti, TiB2, AlN, and composites of W-Ti and Al-AlN. Oxygen content in SFE synthesized nano- AlN has been measured by neutron activation analysis to be as low as 0.54wt.%, as compared to over 5wt.% for unprotected AlN of comparable size. The overall objective of this work is to study the SFE process and nano-encapsulation so that they can be used to produce novel and superior materials. SFE experiments in microgravity allow the study of flame and particle dynamics without the influence of buoyancy forces. Spherical sodium-halide flames are produced in microgravity by ejecting the halide from a spherical porous burner into a quiescent atmosphere of sodium vapor and argon. Experiments are performed in the 2.2 sec Drop Tower at the NASA-Glenn Research Center. Numerical models of the flame and particle dynamics were developed and are compared with the experimental results.

Beyond Serial Founder Effects: The Impact of Admixture and Localized Gene Flow on Patterns of Regional Genetic Diversity.

PubMed

Hunley, Keith L; Cabana, Graciela S

2016-07-01

Geneticists have argued that the linear decay in within-population genetic diversity with increasing geographic distance from East Africa is best explained by a phylogenetic process of repeated founder effects, growth, and isolation. However, this serial founder effect (SFE) process has not yet been adequately vetted against other evolutionary processes that may also affect geospatial patterns of diversity. Additionally, studies of the SFE process have been largely based on a limited 52-population sample. Here, we assess the effects of founder effect, admixture, and localized gene flow processes on patterns of global and regional diversity using a published data set of 645 autosomal microsatellite genotypes from 5,415 individuals in 248 widespread populations. We used a formal tree-fitting approach to explore the role of founder effects. The approach involved fitting global and regional population trees to extant patterns of gene diversity and then systematically examining the deviations in fit. We also informally tested the SFE process using linear models of gene diversity versus waypoint geographic distances from Africa. We tested the role of localized gene flow using partial Mantel correlograms of gene diversity versus geographic distance controlling for the confounding effects of treelike genetic structure. We corroborate previous findings that global patterns of diversity, both within and between populations, are the product of an out-of-Africa SFE process. Within regions, however, diversity within populations is uncorrelated with geographic distance from Africa. Here, patterns of diversity have been largely shaped by recent interregional admixture and secondary range expansions. Our detailed analyses of the pattern of diversity within and between populations reveal that the signatures of different evolutionary processes dominate at different geographic scales. These findings have important implications for recent publications on the biology of race.

ICME for Crashworthiness of TWIP Steels: From Ab Initio to the Crash Performance

NASA Astrophysics Data System (ADS)

Güvenç, O.; Roters, F.; Hickel, T.; Bambach, M.

2015-01-01

During the last decade, integrated computational materials engineering (ICME) emerged as a field which aims to promote synergetic usage of formerly isolated simulation models, data and knowledge in materials science and engineering, in order to solve complex engineering problems. In our work, we applied the ICME approach to a crash box, a common automobile component crucial to passenger safety. A newly developed high manganese steel was selected as the material of the component and its crashworthiness was assessed by simulated and real drop tower tests. The crashworthiness of twinning-induced plasticity (TWIP) steel is intrinsically related to the strain hardening behavior caused by the combination of dislocation glide and deformation twinning. The relative contributions of those to the overall hardening behavior depend on the stacking fault energy (SFE) of the selected material. Both the deformation twinning mechanism and the stacking fault energy are individually well-researched topics, but especially for high-manganese steels, the determination of the stacking-fault energy and the occurrence of deformation twinning as a function of the SFE are crucial to understand the strain hardening behavior. We applied ab initio methods to calculate the stacking fault energy of the selected steel composition as an input to a recently developed strain hardening model which models deformation twinning based on the SFE-dependent dislocation mechanisms. This physically based material model is then applied to simulate a drop tower test in order to calculate the energy absorption capacity of the designed component. The results are in good agreement with experiments. The model chain links the crash performance to the SFE and hence to the chemical composition, which paves the way for computational materials design for crashworthiness.

The key role of dislocation dissociation in the plastic behaviour of single crystal nickel-based superalloy with low stacking fault energy: Three-dimensional discrete dislocation dynamics modelling

NASA Astrophysics Data System (ADS)

Huang, Minsheng; Li, Zhenhuan

2013-12-01

To model the deformation of single crystal nickel based superalloys (SCNBS) with low stacking fault energy (SFE), three-dimensional discrete dislocation dynamics (3D-DDD) is extended by incorporating dislocation dissociation mechanism. The present 3D-DDD simulations show that, consistent with the existing TEM observation, the leading partial can enter the matrix channel efficiently while the trailing partial can hardly glide into it when the dislocation dissociation is taken into account. To determine whether the dislocation dissociation can occur or not, a critical percolation stress (CPS) based criterion is suggested. According to this CPS criterion, for SCNBS there exists a critical matrix channel width. When the channel width is lower than this critical value, the dislocation tends to dissociate into an extended configuration and vice versa. To clarify the influence of dislocation dissociation on CPS, the classical Orowan formula is improved by incorporating the SFE. Moreover, the present 3D-DDD simulations also show that the yielding stress of SCNBSs with low SFE may be overestimated up to 30% if the dislocation dissociation is ignored. With dislocation dissociation being considered, the size effect due to the width of γ matrix channel and the length of γ‧ precipitates on the stress-strain responses of SCNBS can be enhanced remarkably. In addition, due to the strong constraint effect by the two-phase microstructure in SCNBS, the configuration of formed junctions is quite different from that in single phase crystals such as Cu. The present results not only provide clear understanding of the two-phase microstructure levelled microplastic mechanisms in SCNBSs with low SFE, but also help to develop new continuum-levelled constitutive laws for SCNBSs.

Comparison of the Nanopulse Lithotripter to the Holmium Laser: Stone Fragmentation Efficiency and Impact on Flexible Ureteroscope Deflection and Flow.

PubMed

Kaplan, Adam G; Chen, Tony T; Sankin, Georgy; Yang, Chen; Dale, Joanne A; Simmons, W Neal; Zhong, Pei; Preminger, Glenn M; Lipkin, Michael Eric

2016-11-01

The Nanopulse Lithotripter (NPL; Lithotech Medical, Israel) is a novel intracorporeal device that uses a nanosecond duration electrical discharge through a reusable flexible coaxial probe to endoscopically fragment urinary stones. This device was compared with a holmium laser lithotripsy (HoL) with regard to stone fragmentation efficiency (SFE) and its impact on flexible ureteroscope (URS) deflection and flow of irrigation. Using a custom bench model, a 6 mm BegoStone cylindrical phantom (mixture 5:2) was confined under 0.9% saline atop sequential mesh sieves. The SFE of two NPL probe sizes (2.0F, 3.6F) and two HoL fibers (200, 365 μm) was evaluated using concordant settings of 1 J and 5 Hz. URS deflection and irrigation flow with NPL probes in the working channel were tested in five new fourth generation flexible URS and compared with other adjunct endourologic instruments. The 2.0F NPL showed improved SFE compared with the 200 μm laser (86 mg/min vs 52 mg/min, p = 0.014) as did the 3.6F NPL vs the 365 μm laser (173 mg/min vs 80 mg/min, p = 0.05). The NPL created more 1 to 2 mm fragments; the laser created more dust. URS deflection reduced by 3.75° with the 2.0 NPL probe. URS irrigation flow reduced from 36.5 to 6.3 mL/min with the 2.0F NPL probe. NPL shows improved SFE compared with HoL. Flow with the 2.0F probe is akin to a stone basket. NPL offers an effective alternative to HoL.

Sulfur Speciation and Extraction in Jet A (Briefing Charts)

DTIC Science & Technology

2015-08-16

Extraction fluid: denatured ethanol from Fisher Scientific and deionized water – Jet A fuel , approximately 500-800 ppm sulfur by weight – Data...Outline • Background • Experimental Setup – Extraction of sulfur compounds from fuel to alcohol/water extraction fluid – Each rinse is...Hydrophobic / Oleophillic Membrane Oleophobic / Hydrophillic Membrane Emulsion Phase Fuel Phase Water (Extraction Fluid) Phase DISTRIBUTION A

Comparative analysis of the oil and supercritical CO(2) extract of Artemisia arborescens L. and Helichrysum splendidum (Thunb.) Less.

PubMed

Marongiu, Bruno; Piras, Alessandra; Porcedda, Silvia

2006-05-10

Isolation of volatile concentrate from the dried leaves of Artemisia arborescens and of Helichrysum splendidum has been obtained by supercritical extraction with carbon dioxide. To obtain a pure volatile extract devoid of cuticular waxes, the extraction products were fractionated in two separators operating in series. A good extraction process was obtained operating at 90 bar and 50 degrees C in the extraction vessel, at 90 bar and at -5 degrees C in the first separator and at a pressure between 20 and 15 bar and temperatures in the range 10-20 degrees C in the second one. The composition of the volatile concentrate has been analyzed by GC/MS. The volatile concentrate of A. arborescens was found to contain: trans-thujone (13.96%), camphor (6.15%) and chamazulene (5.95%). The main constituents in the extract of H. splendidum were: germacrene D-4-ol (17.08%), germacrene D (9.04%), bicyclogermacrene (8.79%) and delta-cadinene (8.43%). A comparison with the oils obtained by hydrodistillation is also given. The differences observed between the composition of the SFE volatile concentrates and of the hydrodistilled (HD) oils were relevant. Indeed, the HD oils had a blue color whereas the volatile concentrates were pale yellow. The HD oil of H. splendidum had a blue color due to the presence of guaiazulene (0.42% vs 0%), whereas the coloration of HD oil of A. arborecens was due to the high concentration of chamazulene (26.64% vs 3.37%).

Assessment of critical-fluid extractions in the process industries

NASA Technical Reports Server (NTRS)

1982-01-01

The potential for critical-fluid extraction as a separation process for improving the productive use of energy in the process industries is assessed. Critical-fluid extraction involves the use of fluids, normally gaseous at ambient conditions, as extraction solvents at temperatures and pressures around the critical point. Equilibrium and kinetic properties in this regime are very favorable for solvent applications, and generally allow major reductions in the energy requirements for separating and purifying chemical component of a mixture.

Stacking fault energy of face-centered cubic metals: thermodynamic and ab initio approaches

NASA Astrophysics Data System (ADS)

Li, Ruihuan; Lu, Song; Kim, Dongyoo; Schönecker, Stephan; Zhao, Jijun; Kwon, Se Kyun; Vitos, Levente

2016-10-01

The formation energy of the interface between face-centered cubic (fcc) and hexagonal close packed (hcp) structures is a key parameter in determining the stacking fault energy (SFE) of fcc metals and alloys using thermodynamic calculations. It is often assumed that the contribution of the planar fault energy to the SFE has the same order of magnitude as the bulk part, and thus the lack of precise information about it can become the limiting factor in thermodynamic predictions. Here, we differentiate between the interfacial energy for the coherent fcc(1 1 1)/hcp(0 0 0 1) interface and the ‘pseudo-interfacial energy’ that enters the thermodynamic expression for the SFE. Using first-principles calculations, we determine the coherent and pseudo-interfacial energies for six elemental metals (Al, Ni, Cu, Ag, Pt, and Au) and three paramagnetic Fe-Cr-Ni alloys. Our results show that the two interfacial energies significantly differ from each other. We observe a strong chemistry dependence for both interfacial energies. The calculated pseudo-interfacial energies for the Fe-Cr-Ni steels agree well with the available literature data. We discuss the effects of strain on the description of planar faults via thermodynamic and ab initio approaches.

Stacking fault energy of face-centered cubic metals: thermodynamic and ab initio approaches.

PubMed

Li, Ruihuan; Lu, Song; Kim, Dongyoo; Schönecker, Stephan; Zhao, Jijun; Kwon, Se Kyun; Vitos, Levente

2016-10-05

The formation energy of the interface between face-centered cubic (fcc) and hexagonal close packed (hcp) structures is a key parameter in determining the stacking fault energy (SFE) of fcc metals and alloys using thermodynamic calculations. It is often assumed that the contribution of the planar fault energy to the SFE has the same order of magnitude as the bulk part, and thus the lack of precise information about it can become the limiting factor in thermodynamic predictions. Here, we differentiate between the interfacial energy for the coherent fcc(1 1 1)/hcp(0 0 0 1) interface and the 'pseudo-interfacial energy' that enters the thermodynamic expression for the SFE. Using first-principles calculations, we determine the coherent and pseudo-interfacial energies for six elemental metals (Al, Ni, Cu, Ag, Pt, and Au) and three paramagnetic Fe-Cr-Ni alloys. Our results show that the two interfacial energies significantly differ from each other. We observe a strong chemistry dependence for both interfacial energies. The calculated pseudo-interfacial energies for the Fe-Cr-Ni steels agree well with the available literature data. We discuss the effects of strain on the description of planar faults via thermodynamic and ab initio approaches.

Guatemalan school food environment: impact on schoolchildren's risk of both undernutrition and overweight/obesity

PubMed Central

Pehlke, Elisa L.; Letona, Paola; Hurley, Kristen; Gittelsohn, Joel

2016-01-01

Guatemala suffers the double burden of malnutrition with high rates of stunting alongside increasing childhood overweight/obesity. This study examines the school food environment (SFE) at low-income Guatemalan elementary schools and discusses its potential impact on undernutrition and overweight/obesity. From July through October 2013, direct observations, in-depth interviews with school principals (n = 4) and food kiosk vendors (n = 4, 2 interviews each) and also focus groups (FGs) with children (n = 48, 8 FGs) were conducted. The SFE comprises food from school food kiosks (casetas); food from home or purchased in the street; and food provided by the school (refacción). School casetas, street vendors and children's parents largely provide sandwiches, calorie-rich snacks and sugar-sweetened beverages. Refacción typically serves energy dense atol, a traditional beverage. The current school food program (refacción), the overall SFE and the roles/opinions of vendors and principals reveal persistent anxiety concerning undernutrition and insufficient concern for overweight/obesity. Predominant concern for elementary schoolchildren remains focused on undernutrition. However, by the time children reach elementary school (ages 6–12+), food environments should encourage dietary behaviors to prevent childhood overweight/obesity. PMID:25823911

METHOD FOR THE SUPERCRITICAL FLUID EXTRACTION OF SOILS/SEDIMENTS

EPA Science Inventory

Supercritical fluid extraction has been publicized as an extraction method which has several advantages over conventional methods, and it is expected to result in substantial cost and labor savings. This study was designed to evaluate the feasibility of using supercritical fluid ...

Determination of major aromatic constituents in vanilla using an on-line supercritical fluid extraction coupled with supercritical fluid chromatography.

PubMed

Liang, Yanshan; Liu, Jiaqi; Zhong, Qisheng; Shen, Lingling; Yao, Jinting; Huang, Taohong; Zhou, Ting

2018-04-01

An on-line supercritical fluid extraction coupled with supercritical fluid chromatography method was developed for the determination of four major aromatic constituents in vanilla. The parameters of supercritical fluid extraction were systematically investigated using single factor optimization experiments and response surface methodology by a Box-Behnken design. The modifier ratio, split ratio, and the extraction temperature and pressure were the major parameters which have significant effects on the extraction. While the static extraction time, dynamic extraction time, and recycle time had little influence on the compounds with low polarity. Under the optimized conditions, the relative extraction efficiencies of all the constituents reached 89.0-95.1%. The limits of quantification were in the range of 1.123-4.747 μg. The limits of detection were in the range of 0.3368-1.424 μg. The recoveries of the four analytes were in the range of 76.1-88.9%. The relative standard deviations of intra- and interday precision ranged from 4.2 to 7.6%. Compared with other off-line methods, the present method obtained higher extraction yields for all four aromatic constituents. Finally, this method has been applied to the analysis of vanilla from different sources. On the basis of the results, the on-line supercritical fluid extraction-supercritical fluid chromatography method shows great promise in the analysis of aromatic constituents in natural products. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Application of supercritical fluid carbon dioxide to the extraction and analysis of lipids.

PubMed

Lee, Jae Won; Fukusaki, Eiichiro; Bamba, Takeshi

2012-10-01

Supercritical carbon dioxide (SCCO(2)) is an ecofriendly supercritical fluid that is chemically inert, nontoxic, noninflammable and nonpolluting. As a green material, SCCO(2) has desirable properties such as high density, low viscosity and high diffusivity that make it suitable for use as a solvent in supercritical fluid extraction, an effective and environment-friendly analytical method, and as a mobile phase for supercritical fluid chromatography, which facilitates high-throughput, high-resolution analysis. Furthermore, the low polarity of SCCO(2) is suitable for the extraction and analysis of hydrophobic compounds. The growing concern surrounding environmental pollution has triggered the development of green analysis methods based on the use of SCCO(2) in various laboratories and industries. SCCO(2) is becoming an effective alternative to conventional organic solvents. In this review, the usefulness of SCCO(2) in supercritical fluid extraction and supercritical fluid chromatography for the extraction and analysis of lipids is described.

Enrichment of prostate cancer stem cells from primary prostate cancer cultures of biopsy samples

PubMed Central

Wang, Shunqi; Huang, Shengsong; Zhao, Xin; Zhang, Qimin; Wu, Min; Sun, Feng; Han, Gang; Wu, Denglong

2014-01-01

This study was to enrich prostate cancer stem cells (PrCSC) from primary prostate cancer cultures (PPrCC). Primary prostate cancer cells were amplified in keratinocyte serum-free medium with epidermal growth factor (EGF) and bovine pituitary extract (BPE), supplemented with leukemia inhibitory factor (LIF), stem cell factor (SCF) and cholera toxin. After amplification, cells were transferred into ultra-low attachment dishes with serum-free DMEM/F12 medium, supplemented with EGF, basic fibroblast growth factor (bFGF), bovine serum albumin (BSA), insulin, and N2 nutrition. Expression of cell-type-specific markers was determined by RT-qPCR and immunostaining. Tumorigenicity of enriched PrCSC was determined by soft agar assay and xenograft assay in NOD/SCID mice. Biopsy samples from 19 confirmed prostate cancer patients were used for establishing PPrCC, and 18 cases (95%) succeeded. Both basal marker (CK5) and luminal markers (androgen receptor and CK8) strongly co-expressed in most of PPrCC, indicating their basal epithelial origin. After amplification under adherent culture condition in vitro, transient amplifying cells were the dominant cells. Sphere formation efficiency (SFE) of passaged PPrCC was about 0.5%, which was 27 times lower than SFE of LNCaP (13.67%) in the same condition. Compared with adherent cells from PPrCC, prostasphere from PPrCC showed up regulated stem cell markers and increased tumorigenic potential in soft-agar assay. However, spheroid cells from PPrCC prostasphere failed to initiate tumor in xenograft assay in 6 months. Thus, PPrCC can be established and amplified from prostate cancer biopsy samples. Our modified sphere culture system can enrich PrCSC from PPrCC. PMID:24427338

[Optimization of supercritical fluid extraction of bioactive components in Ligusticum chuanxiong by orthogonal array design].

PubMed

Hu, Li-Cui; Wu, Xun; Yang, Xue-Dong

2013-10-01

With the yields of ferulic acid, coniferylferulate, Z-ligustilide, senkyunolide A, butylidenephthalide, butylphthalide, senkyunolide I, senkyunolide H, riligustilide, levistolide A, and total pharmacologically active ingredient as evaluation indexes, the extraction of Ligusticum chuanxiong by supercritical fluid technology was investigated through an orthogonal experiment L9 (3(4)). Four factors, namely temperature, pressure, flow rate of carbon dioxide, co-solvent concentration of the supercritical fluid, were investigated and optimized. Under the optimized conditions, namely 65 degrees C of temperature, 35 MPa of pressure, 1 L x min(-1) of CO2 flow rate, 8% of co-solvent concetration, supercritical fluid extraction could achieve a better yield than the conventional reflux extraction using methanol. And the supercritical fluid extraction process was validated to be stable and reliable.

Star Formation in Orion A : Towards Resolved Maps of SFR and SFE

NASA Astrophysics Data System (ADS)

Großschedl, Josefa; Alves, J.; Ascenso, J.; Bouy, H.

2017-06-01

The OrionA GMC is a benchmark for studying star formation. Our goal is to construct a map of SFR and SFE (with Herschel) across the entire complex, for which it is critical to have a reliable and complete sample of YSOs. In this work we present a refined catalogue of YSOs, making use of a new deep NIR survey with VISTA, complemented with archival data. The survey allows us to rule out false positives from previous samples (galaxies, cloud edges, etc.). To add new candidates we use MIR data from WISE for areas not covered by Spitzer to get a complete census of the spatial distribution of YSOs.

Pressurized fluid extraction of essential oil from Lavandula hybrida using a modified supercritical fluid extractor and a central composite design for optimization.

PubMed

Kamali, Hossein; Jalilvand, Mohammad Reza; Aminimoghadamfarouj, Noushin

2012-06-01

Essential oil components were extracted from lavandin (Lavandula hybrida) flowers using pressurized fluid extraction. A central composite design was used to optimize the effective extraction variables. The chemical composition of extracted samples was analyzed by a gas chromatograph-flame ionization detector column. For achieving 100% extraction yield, the temperature, pressure, extraction time, and the solvent flow rate were adjusted at 90.6°C, 63 bar, 30.4 min, and 0.2 mL/min, respectively. The results showed that pressurized fluid extraction is a practical technique for separation of constituents such as 1,8-cineole (8.1%), linalool (34.1%), linalyl acetate (30.5%), and camphor (7.3%) from lavandin to be applied in the food, fragrance, pharmaceutical, and natural biocides industries. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A FLUID SORBENT RECYCLING DEVICE FOR INDUSTRIAL FLUID USERS

EPA Science Inventory

A roller compression Extractor® that extracts fluids from reusable sorbent pads was evaluated as a method of waste reduction. The extraction device, evaluated for industrial fluid users in New Jersey, was found to be effective in recycling unpleated sorbent pads, especially ...

Plasma proteins in the acquired denture pellicle enhance substrate surface free energy and Candida albicans phospholipase and proteinase activities.

PubMed

Custodio, William; Silva, Wander J; Paes Leme, Adriana F; Cury, Jaime A; Del Bel Cury, Altair A

2015-11-01

The objective of the present study was to determine if blood plasma proteins could change the proteome of the acquired denture pellicle by label-free quantitative proteomics. As pellicle proteome modulates the interaction between substrates and Candida cells, we investigated its effect on the surface free energy (SFE) of the coated resin and on Candida albicans phospholipase and aspartyl proteinase activities. Poly(methylmethacrylate) discs were exposed to saliva (control) or saliva enriched with blood plasma (experimental group). The pellicle proteome was analyzed by mass spectrometry coupled with liquid chromatography. SFE was determined by acid-base technique. After biofilm formation, phospholipase and proteinase activities were determined accordingly to classic plate methods. Data were analyzed by two-way anova and Tukey test (P < 0.05). α-Amylase, cystatins, mucins, and host-immune system proteins were the main proteins identified in the control group. Fibrinogen and albumin were observed only in the experimental group. Coated discs of the experimental group presented an increased SFE (P < 0.05). For both enzymes tested, the experimental group showed higher proteolytic activity (P < 0.001). Blood plasma changes the proteome of the acquired denture pellicle, increasing surface free energy and the activity of Candida albicans phospholipase and aspartyl proteinase. © 2014 Wiley Publishing Asia Pty Ltd.

Guatemalan school food environment: impact on schoolchildren's risk of both undernutrition and overweight/obesity.

PubMed

Pehlke, Elisa L; Letona, Paola; Hurley, Kristen; Gittelsohn, Joel

2016-09-01

Guatemala suffers the double burden of malnutrition with high rates of stunting alongside increasing childhood overweight/obesity. This study examines the school food environment (SFE) at low-income Guatemalan elementary schools and discusses its potential impact on undernutrition and overweight/obesity. From July through October 2013, direct observations, in-depth interviews with school principals (n = 4) and food kiosk vendors (n = 4, 2 interviews each) and also focus groups (FGs) with children (n = 48, 8 FGs) were conducted. The SFE comprises food from school food kiosks (casetas); food from home or purchased in the street; and food provided by the school (refacción). School casetas, street vendors and children's parents largely provide sandwiches, calorie-rich snacks and sugar-sweetened beverages. Refacción typically serves energy dense atol, a traditional beverage. The current school food program (refacción), the overall SFE and the roles/opinions of vendors and principals reveal persistent anxiety concerning undernutrition and insufficient concern for overweight/obesity. Predominant concern for elementary schoolchildren remains focused on undernutrition. However, by the time children reach elementary school (ages 6-12+), food environments should encourage dietary behaviors to prevent childhood overweight/obesity. © The Author 2015. Published by Oxford University Press.

Nitrous oxide emission potentials of Burkholderia species isolated from the leaves of a boreal peat moss Sphagnum fuscum.

PubMed

Nie, Yanxia; Li, Li; Wang, Mengcen; Tahvanainen, Teemu; Hashidoko, Yasuyuki

2015-01-01

Using a culture-based nitrous oxide (N2O) emission assay, three active N2O emitters were isolated from Sphagnum fuscum leaves and all identified as members of Burkholderia. These isolates showed N2O emission in the medium supplemented with [Formula: see text] but not with [Formula: see text], and Burkholderia sp. SF-E2 showed the most efficient N2O emission (0.20 μg·vial(-1)·day(-1)) at 1.0 mM KNO3. In Burkholderia sp. SF-E2, the optimum pH for N2O production was 5.0, close to that of the phyllosphere of Sphagnum mosses, while the optimum temperature was uniquely over 30 °C. The stimulating effect of additional 1.5 mM sucrose on N2O emission was ignorable, but Burkholderia sp. SF-E2 upon exposure to 100 mg·L(-1) E-caffeic acid showed uniquely 67-fold higher N2O emission. All of the three N2O emitters were negative in both acetylene inhibition assay and PCR assay for nosZ-detection, suggesting that N2O reductase or the gene itself is missing in the N2O-emitting Burkholderia.

Graft shrinkage and survival rate of implants after sinus floor elevation using a nanocrystalline hydroxyapatite embedded in silica gel matrix: a 1-year prospective study.

PubMed

El Hage, Marc; Abi Najm, Semaan; Bischof, Mvark; Nedir, Rabah; Carrel, Jean-Pierre; Bernard, Jean-Pierre

2012-06-01

The aims of this study were (1) to evaluate the vertical shrinkage percentage of nanocrystalline hydroxyapatite embedded in silica gel used for maxillary sinus floor elevation (SFE) and (2) to determine the survival rate of the implants 1 year after placement in the healed grafted sinuses. Eleven maxillary sinuses were augmented in eight patients with NanoBone. After a healing period averaging 14.42 months, 19 implants were placed and followed up with clinical and radiographic evaluation. Panoramic radiographs were taken immediately after SFE and at 12 months after grafting. Measurements of changes in height were made by a computerized measuring technique using an image editing software. The mean graft height shrinkage percentage at 12 months after surgery was 8.84% (±5.32). One implant was lost before loading. All the 18 remaining osseointegrated implants received the prosthetic rehabilitation and were controlled after 3 months of functional loading. The implant survival rate at the 1-year interval was 94.74%. A 100% NanoBone alloplastic graft used in lateral SFE procedures presented limited height shrinkage. Implants placed in these grafted sinuses showed survival rates similar to those found in published data. These results should be interpreted cautiously considering the study's reduced sample size.

Phylogenetic profiles reveal structural/functional determinants of TRPC3 signal-sensing antennae

PubMed Central

Ko, Kyung Dae; Bhardwaj, Gaurav; Hong, Yoojin; Chang, Gue Su; Kiselyov, Kirill

2009-01-01

Biochemical assessment of channel structure/function is incredibly challenging. Developing computational tools that provide these data would enable translational research, accelerating mechanistic experimentation for the bench scientist studying ion channels. Starting with the premise that protein sequence encodes information about structure, function and evolution (SF&E), we developed a unified framework for inferring SF&E from sequence information using a knowledge-based approach. The Gestalt Domain Detection Algorithm-Basic Local Alignment Tool (GDDA-BLAST) provides phylogenetic profiles that can model, ab initio, SF&E relationships of biological sequences at the whole protein, single domain and single-amino acid level.1,2 In our recent paper,4 we have applied GDDA-BLAST analysis to study canonical TRP (TRPC) channels1 and empirically validated predicted lipid-binding and trafficking activities contained within the TRPC3 TRP_2 domain of unknown function. Overall, our in silico, in vitro, and in vivo experiments support a model in which TRPC3 has signal-sensing antennae which are adorned with lipid-binding, trafficking and calmodulin regulatory domains. In this Addendum, we correlate our functional domain analysis with the cryo-EM structure of TRPC3.3 In addition, we synthesize recent studies with our new findings to provide a refined model on the mechanism(s) of TRPC3 activation/deactivation. PMID:19704910

Antitumor activity of Annona squamosa seed oil.

PubMed

Chen, Yong; Chen, Yayun; Shi, Yeye; Ma, Chengyao; Wang, Xunan; Li, Yue; Miao, Yunjie; Chen, Jianwei; Li, Xiang

2016-12-04

Custard apple (Annona squamosa Linn.) is an edible tropical fruit, and its seeds have been used to treat "malignant sore" (cancer) and other usage as insecticide. A comparison of extraction processes, chemical composition analysis and antitumor activity of A. squamosa seed oil (ASO) were investigated. The optimal extraction parameters of ASO were established by comparing percolation, soxhlet, ultrasonic and SFE-CO 2 extraction methods. The chemical composition of fatty acid and content of total annonaceous acetogenins (ACGs) of ASO was investigated by GC-MS and colorimetric assay, and anti-tumor activity of ASO was tested using H 22 xenografts bearing mice. The optimal extraction parameters of ASO were obtained as follows: using soxhlet extraction method with extraction solvent of petroleum ether, temperature of 80°C, and extraction time of 90min. Under these conditions, the yield of ASO was 22.65%. GC-MS analysis results showed that the main chemical compositions of fatty acid of ASO were palmitic acid (9.92%), linoleic acid (20.49%), oleic acid (56.50%) and stearic acid (9.14%). The total ACGs content in ASO was 41.00mg/g. ASO inhibited the growth of H 22 tumor cells in mice with a maximum inhibitory rate of 53.54% by oral administration. Furthermore, it was found that ASO exerted an antitumor effect via decreasing interleukin-6 (IL-6), janus kinase (Jak) and phosphorylated signal transducers and activators of transcription (p-Stat3) expression. The results demonstrated that ASO suppressed the H 22 solid tumor development may due to its main chemical constituents unsaturated fatty acid and ACGs via IL-6/Jak/Stat3 pathway. ASO may be a potential candidate for the treatment of cancer. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

A case study of an iron-deficient female Olympic 1500-m runner.

PubMed

Pedlar, Charles R; Whyte, Gregory P; Burden, Richard; Moore, Brian; Horgan, Gill; Pollock, Noel

2013-11-01

This case study examines the impact of low serum ferritin (sFe) on physiological assessment measures and performance in a young female 1500-m runner undertaking approximately 95-130 km/wk training. The study spans 4 race seasons and an Olympic Games. During this period, 25 venous blood samples were analyzed for sFe and hemoglobin (Hb); running economy, VO(2max), and lactate threshold were measured on 6 occasions separated by 8-10 mo. Training was carefully monitored including 65 monitored treadmill training runs (targeting an intensity associated with the onset of blood lactate accumulation) using blood lactate and heart rate. Performances at competitive track events were recorded. All data were compared longitudinally. Mean sFe was 24.5 ± 7.6 μg/L (range 10-47), appearing to be in gradual decline with the exception of 2 data points (37 and 47 μg/L) after parenteral iron injections before championships, when the lowest values tended to occur, coinciding with peak training volumes. Each season, 1500-m performance improved, from 4:12.8 in year 1 to 4:03.5 in year 4. VO(2max) (69.8 ± 2.0 mL · kg(-1) · min(-1)) and running economy (%VO(2max) at a fixed speed of 16 km/h; max 87.8%, min 80.3%) were stable across time and lactate threshold improved (from 14 to 15.5 km/h). Evidence of anemia (Hb <12 g/dL) was absent. These unique data demonstrate that in 1 endurance athlete, performance can continue to improve despite an apparent iron deficiency. Raising training volume may have caused increased iron utilization; however, the effect of this on performance is unknown. Iron injections were effective in raising sFe in the short term but did not appear to affect the long-term pattern.

Effect of Collagen Matrix Saturation on the Surface Free Energy of Dentin using Different Agents.

PubMed

de Almeida, Leopoldina de Fátima Dantas; Souza, Samilly Evangelista; Sampaio, Aline Araújo; Cavalcanti, Yuri Wanderley; da Silva, Wander José; Del Bel Cur, Altair A; Hebling, Josimeri

2015-07-01

The surface free energy of conditioned-dentin is one of the factors that interfere with monomeric infiltration of the interfibrillar spaces. Saturation of the tooth matrix with different substances may modulate this energy and, consequently, the wettability of the dentin. To evaluate the influence of different substances used to saturate conditioned-dentin on surface free energy (SFE) of this substrate. Dentin blocks (4 × 7 × 1 mm, n = 6/ group), obtained from the roots of bovine incisors, were etched using phosphoric acid for 15 seconds, rinsed and gently dried. The surfaces were treated for 60 seconds with: ultra-purified water (H20-control); ethanol (EtOH), acetone (ACT), chlorhexidine (CHX), ethylenediaminetetraacetic acid (EDTA); or sodium hypochlorite (NaOCl). The tooth surfaces were once again dried with absorbent paper and prepared for SFE evaluation using three standards: water, formamide and bromonaphthalene. Analysis of variance (ANOVA) and Dunnet's tests (a = 0.05) were applied to the data. Ethylenediaminetetraacetic acid was the only substance that caused a change to the contact angle for the standards water and formamide, while only EtOH influenced the angles formed between formamide and the dentin surface. None of the substances exerted a significant effect for bromonaphtha-lene. In comparison to the control, only EDTA and NaOCl altered both polar components of the SFE. Total SFE was increased by saturation of the collagen matrix by EDTA and reduced when NaOCl was used. Saturation of the collagen matrix by EDTA and EtOH changed the surface free energy of the dentin. In addition, the use of NaOCl negatively interfered with the properties evaluated. The increase of surface free energy and wettability of the dentin surface would allow higher penetration of the the adhesive system, which would be of importance to the clinical success of resin-dentin union.

Influence of the redox active ligand on the reactivity and electronic structure of a series of Fe(TIM) complexes.

PubMed

Hess, Corinna R; Weyhermüller, Thomas; Bill, Eckhard; Wieghardt, Karl

2010-06-21

The redox properties of Fe and Zn complexes coordinated by an alpha-diimine based N(4)-macrocyclic ligand (TIM) have been examined using spectroscopic methods and density functional theory (DFT) computational analysis. DFT results on the redox series of [Zn(TIM*)](n) and [Fe(TIM*)](n) molecules indicate the preferential reduction of the alpha-diimine ligand moiety. In addition to the previously reported [Fe(TIM*)](2) dimer, we have now synthesized and characterized a further series of monomeric and dimeric complexes coordinated by the TIM ligand. This includes the five-coordinate monomeric [Fe(TIM*)I], the neutral and cationic forms of a monomeric phosphite adduct, [Fe(TIM*)(P(OPh)(3))] and [Fe(TIM*)(P(OPh)(3))](PF(6)), as well as a binuclear hydroxy-bridged complex, [{Fe(TIM*)}(2)(mu-OH)](PF(6)). Experimental and computational data for these synthetic compounds denote the presence of ferrous and ferric species, suggesting that the alpha-diimine based macrocycles do not readily support the formation of formally low-valent (M(0) or M(I)) metal complexes as previously speculated. Magnetochemical, Mossbauer, electron paramagnetic resonance (EPR), and electronic spectral data have been employed to experimentally determine the oxidation state of the central metal ion and of the macrocyclic ligand (TIM*) in each compound. The series of compounds is described as follows: [Fe(II)(TIM(0))(CH(3)CN(2))](2+), S(Fe) = S(T) = 0; [Fe(2.5)(TIM(2.5-))](2), S(T) = 1; [{Fe(III)(TIM(2-))}(2)(mu-OH)](+), S(Fe) = 3/2, S(T) = 0; [Fe(III)(TIM(2-))I], S(Fe) = 3/2, S(T) = 1/2; [Fe(II)(TIM(2-))(P(OPh(3)))], S(Fe) = S(T) = 0; and [Fe(II)(TIM(1-))(P(OPh(3)))](1+)/[Fe(I)(TIM(0))(P(OPh(3)))](1+), S(T) = 1/2. The results have been corroborated by DFT calculations.

Models of supply function equilibrium with applications to the electricity industry

NASA Astrophysics Data System (ADS)

Aromi, J. Daniel

Electricity market design requires tools that result in a better understanding of incentives of generators and consumers. Chapter 1 and 2 provide tools and applications of these tools to analyze incentive problems in electricity markets. In chapter 1, models of supply function equilibrium (SFE) with asymmetric bidders are studied. I prove the existence and uniqueness of equilibrium in an asymmetric SFE model. In addition, I propose a simple algorithm to calculate numerically the unique equilibrium. As an application, a model of investment decisions is considered that uses the asymmetric SFE as an input. In this model, firms can invest in different technologies, each characterized by distinct variable and fixed costs. In chapter 2, option contracts are introduced to a supply function equilibrium (SFE) model. The uniqueness of the equilibrium in the spot market is established. Comparative statics results on the effect of option contracts on the equilibrium price are presented. A multi-stage game where option contracts are traded before the spot market stage is considered. When contracts are optimally procured by a central authority, the selected profile of option contracts is such that the spot market price equals marginal cost for any load level resulting in a significant reduction in cost. If load serving entities (LSEs) are price takers, in equilibrium, there is no trade of option contracts. Even when LSEs have market power, the central authority's solution cannot be implemented in equilibrium. In chapter 3, we consider a game in which a buyer must repeatedly procure an input from a set of firms. In our model, the buyer is able to sign long term contracts that establish the likelihood with which the next period contract is awarded to an entrant or the incumbent. We find that the buyer finds it optimal to favor the incumbent, this generates more intense competition between suppliers. In a two period model we are able to completely characterize the optimal mechanism.

Morphometric approach to thermodynamic quantities of solvation of complex molecules: Extension to multicomponent solvent

NASA Astrophysics Data System (ADS)

Kodama, Ryota; Roth, Roland; Harano, Yuichi; Kinoshita, Masahiro

2011-07-01

The morphometric approach (MA) is a powerful tool for calculating a solvation free energy (SFE) and related quantities of solvation thermodynamics of complex molecules. Here, we extend it to a solvent consisting of m components. In the integral equation theories, the SFE is expressed as the sum of m terms each of which comprises solute-component j correlation functions (j = 1, …, m). The MA is applied to each term in a formally separate manner: The term is expressed as a linear combination of the four geometric measures, excluded volume, solvent-accessible surface area, and integrated mean and Gaussian curvatures of the accessible surface, which are calculated for component j. The total number of the geometric measures or the coefficients in the linear combinations is 4m. The coefficients are determined in simple geometries, i.e., for spherical solutes with various diameters in the same multicomponent solvent. The SFE of the spherical solutes are calculated using the radial-symmetric integral equation theory. The extended version of the MA is illustrated for a protein modeled as a set of fused hard spheres immersed in a binary mixture of hard spheres. Several mixtures of different molecular-diameter ratios and compositions and 30 structures of the protein with a variety of radii of gyration are considered for the illustration purpose. The SFE calculated by the MA is compared with that by the direct application of the three-dimensional integral equation theory (3D-IET) to the protein. The deviations of the MA values from the 3D-IET values are less than 1.5%. The computation time required is over four orders of magnitude shorter than that in the 3D-IET. The MA thus developed is expected to be best suited to analyses concerning the effects of cosolvents such as urea on the structural stability of a protein.

Application of response surface methodology to optimise supercritical carbon dioxide extraction of volatile compounds from Crocus sativus.

PubMed

Shao, Qingsong; Huang, Yuqiu; Zhou, Aicun; Guo, Haipeng; Zhang, Ailian; Wang, Yong

2014-05-01

Crocus sativus has been used as a traditional Chinese medicine for a long time. The volatile compounds of C. sativus appear biologically active and may act as antioxidants as well as anticonvulsants, antidepressants and antitumour agents. In order to obtain the highest possible yield of essential oils from C. sativus, response surface methodology was employed to optimise the conditions of supercritical fluid carbon dioxide extraction of the volatile compounds from C. sativus. Four factorswere investigated: temperature, pressure, extraction time and carbon dioxide flow rate. Furthermore, the chemical compositions of the volatile compounds extracted by supercritical fluid extraction were compared with those obtained by hydro-distillation and Soxhlet extraction. The optimum extraction conditions were found to be: optimised temperature 44.9°C, pressure 34.9 MPa, extraction time 150.2 min and CO₂ flow rate 10.1 L h⁻¹. Under these conditions, the mean extraction yield was 10.94 g kg⁻¹. The volatile compounds extracted by supercritical fluid extraction and Soxhlet extraction contained a large amount of unsaturated fatty acids. Response surface methodology was successfully applied for supercritical fluid CO₂ extraction optimisation of the volatile compounds from C. sativus. The study showed that pressure and CO₂ flow rate had significant effect on volatile compounds yield produced by supercritical fluid extraction. This study is beneficial for the further research operating on a large scale. © 2013 Society of Chemical Industry.

[Study on the dynamic model with supercritical CO2 fluid extracting the lipophilic components in Panax notoginseng].

PubMed

Duan, Xian-Chun; Wang, Yong-Zhong; Zhang, Jun-Ru; Luo, Huan; Zhang, Heng; Xia, Lun-Zhu

2011-08-01

To establish a dynamics model for extracting the lipophilic components in Panax notoginseng with supercritical carbon dioxide (CO2). Based on the theory of counter-flow mass transfer and the molecular mass transfer between the material and the supercritical CO2 fluid under differential mass-conservation equation, a dynamics model was established and computed to compare forecasting result with the experiment process. A dynamics model has been established for supercritical CO2 to extract the lipophilic components in Panax notoginseng, the computed result of this model was consistent with the experiment process basically. The supercritical fluid extract dynamics model established in this research can expound the mechanism in the extract process of which lipophilic components of Panax notoginseng dissolve the mass transfer and is tallied with the actual extract process. This provides certain instruction for the supercritical CO2 fluid extract' s industrialization enlargement.

Effect temperature of supercritical CO2 fluid extraction on phytochemical analysis and antioxidant activity of Zingiber officinale Roscoe

NASA Astrophysics Data System (ADS)

Sondari, Dewi; Irawadi, Tun Tedja; Setyaningsih, Dwi; Tursiloadi, Silvester

2017-11-01

Supercritical fluid extraction of Zingiber officinale Roscoe has been carried out at a pressure of 16 MPa, with temperatures between 20-40 °C, during extraction time of 6 hours and the flow rate of CO2 fluid 5.5 ml/min. The result of supercritical method was compared with the extraction maceration using a mixture of water and ethanol (70% v/v) for 24 hours. The main content in ginger that has a main role as an antioxidant is a gingerol compound that can help neutralize the damaging effects caused by free radicals in the body, as anti-coagulant, and inhibit the occurrence of blood clots. This study aims to determine the effect of temperature on chemical components contained in rough extract of Zingiber officinale Roscoe and its antioxidant activity, total phenol and total flavonoid content. To determine the chemical components contained in the crude extract of Zingiber officinale Roscoe extracted by supercritical fluid and maceration extraction, GC-MS analysis was performed. Meanwhile, the antioxidant activity of the extract was evaluated based on a 2.2-diphenyl-1-picrylhydrazyl (DPPH) free radical damping method. The results of the analysis show that the result of ginger extract by using the supercritical CO2 extraction method has high antioxidant activity than by using maceration method. The highest total phenol content and total flavonoids were obtained on ginger extraction using supercritical CO2 fluid extraction, indicating that phenol and flavonoid compounds contribute to antioxidant activity. Chromatographic analysis showed that the chemical profile of ginger extract containing oxygenated monoterpenes, monoterpene hydrocarbons, sesquiterpene hydrocarbons, oxygenated monoterpene gingerol and esters. In supercritical fluid extraction, the compounds that can be identified at a temperature of 20-40 °C contain 27 compounds, and 11 compounds from the result of maceration extract. The main component of Zingiber officinale Roscoe extracted using supercritical fluid at a temperature of 40 °C is Hexanal (6.04%), Butan-2-one, 4-(3-hydroxy-2-methoxyphenyl) (27.95%), [6]-Paradol (0.73%), Gingerol (8.22%), Bis (2-ethylhexyl) phthalate (1.62%), α-Citral (12.14%) and α-zingiberene (2.90%). The main component extracts of Zingiber officinale Roscoe by maceration is Hexanal (10.71%), Decanal (3.74%), Butan-2-one, 4-(3-hydroxy-2-methoxyphenyl) (38.33%), Gingerol (4.56%) and Zingiberene (0.99).

Modeling the Kinetics of Root Gravireaction

NASA Astrophysics Data System (ADS)

Kondrachuk, Alexander V.; Starkov, Vyacheslav N.

2011-02-01

The known "sun-flower equation" (SFE), which was originally proposed to model root circumnutating, was used to describe the simplest tip root graviresponse. Two forms of the SFE (integro-differential and differential-delayed) were solved, analyzed and compared with each other. The numerical solutions of these equations were found to be matching with arbitrary accuracy. The analysis of the solutions focused on time-lag effects on the kinetics of tip root bending. The results of the modeling are in good correlation with an experiment at the initial stages of root tips graviresponse. Further development of the model calls for its systematic comparison with some specially designed experiments, which would include measuring the kinetics of root tip bending before gravistimulation over the period of time longer than the time lag.

MEASUREMENT OF PYRETHROID RESIDUES IN ENVIRONMENTAL AND FOOD SAMPLES BY ENHANCED SOLVENT EXTRACTION/SUPERCRITICAL FLUID EXTRACTION COUPLED WITH GAS CHROMATOGRAPHY-TANDEM MASS SPECTROMETRY

EPA Science Inventory

The abstract summarizes pyrethorid methods development research. It provides a summary of sample preparation and analytical techniques such as supercritical fluid extraction, enhance solvent extraction, gas chromatography and tandem mass spectrometry.

Direct online extraction and determination by supercritical fluid extraction with chromatography and mass spectrometry of targeted carotenoids from red Habanero peppers (Capsicum chinense Jacq.).

PubMed

Zoccali, Mariosimone; Giuffrida, Daniele; Dugo, Paola; Mondello, Luigi

2017-10-01

Recently, supercritical fluid chromatography coupled to mass spectrometry has gained attention as a fast and useful technology applied to the carotenoids analysis. However, no reports are available in the literature on the direct online extraction and determination by supercritical fluid extraction with chromatography and mass spectrometry. The aim of this research was the development of an online method coupling supercritical fluid extraction and supercritical fluid chromatography for a detailed targeted native carotenoids characterization in red habanero peppers. The online nature of the system, compared to offline approaches, improves run-to-run precision, enables the setting of batch-type applications, and reduces the risks of sample contamination. The extraction has been optimized using different temperatures, starting from 40°C up to 80°C. Multiple extractions, until depletion, were performed on the same sample to evaluate the extraction yield. The range of the first extraction yield, carried out at 80°C, which was the best extraction temperature, was 37.4-65.4%, with a %CV range of 2-12. Twenty-one targeted analytes were extracted and identified by the developed methodology in less than 17 min, including free, monoesters, and diesters carotenoids, in a very fast and efficient way. Quantification of the β-carotene was carried out by using the optimized conditions. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Extracting metalworking fluid aerosol samples in cassettes by provisional ASTM and NIOSH methods.

PubMed

Harper, Martin

2002-01-01

Recent provisional methods for the determination of metalworking fluid aerosol in workplace air involve a solvent extraction procedure to separate the nonvolatile fraction of the fluid from insoluble material such as metal turnings and dirt. The procedure calls for preweighing a filter (W1) and assembling it into a cassette and taking a sample. In the laboratory the filter is removed from the cassette, desiccated to remove any collected water or other volatile substances, and weighed again (W2). The filter is then extracted in an organic solvent blend, allowed to dry, and weighed a final time (W3). The total weight collected by the filter is given by (W2-W1), and the weight of (nonvolatile) metalworking fluid collected is given by (W2-W3). The extraction step can take place within a cassette housing if it is relatively inert to the solvent blend used. The extraction of four metalworking fluids (straight oil, soluble oil, synthetic and semisynthetic) within disposable polypropylene cassettes was investigated using the same protocol used to evaluate the original method. For all fluids the extraction efficiency was greater than 95% with a precision better than 5%. The mean blank contribution to the extraction step was 16 micrograms. Blanks were also evaluated after storage, and after transport and storage. A small additional blank contribution could be removed by desiccation. The limits of detection and quantitation of the extraction step were calculated to be 28 and 94 micrograms, respectively.

Targeted detection of murine colonic dysplasia in vivo with flexible multispectral scanning fiber endoscopy

NASA Astrophysics Data System (ADS)

Joshi, Bishnu P.; Miller, Sharon J.; Lee, Cameron; Gustad, Adam; Seibel, Eric J.; Wang, Thomas D.

2012-02-01

We demonstrate a multi-spectral scanning fiber endoscope (SFE) that collects fluorescence images in vivo from three target peptides that bind specifically to murine colonic adenomas. This ultrathin endoscope was demonstrated in a genetically engineered mouse model of spontaneous colorectal adenomas based on somatic Apc (adenomatous polyposis coli) gene inactivation. The SFE delivers excitation at 440, 532, 635 nm with <2 mW per channel. The target 7-mer peptides were conjugated to visible organic dyes, including 7-Diethylaminocoumarin-3-carboxylic acid (DEAC) (λex=432 nm, λem=472 nm), 5-Carboxytetramethylrhodamine (5-TAMRA) (λex=535 nm, λem=568 nm), and CF-633 (λex=633 nm, λem=650 nm). Target peptides were first validated using techniques of pfu counting, flow cytometry and previously established methods of fluorescence endoscopy. Peptides were applied individually or in combination and detected with fluorescence imaging. The ability to image multiple channels of fluorescence concurrently was successful for all three channels in vitro, while two channels were resolved simultaneously in vivo. Selective binding of the peptide was evident to adenomas and not to adjacent normal-appearing mucosa. Multispectral wide-field fluorescence detection using the SFE is achievable, and this technology has potential to advance early cancer detection and image-guided therapy in human patients by simultaneously visualizing multiple over expressed molecular targets unique to dysplasia.

Microcystin-LR toxicity on dominant copepods Eurytemora affinis and Pseudodiaptomus forbesi of the upper San Francisco Estuary.

PubMed

Ger, Kemal A; Teh, Swee J; Goldman, Charles R

2009-08-15

This study investigates the toxicity and post-exposure effects of dissolved microcystin (MC-LR) on the dominant copepods of the upper San Francisco Estuary (SFE), where blooms of the toxic cyanobacteria Microcystis aeruginosa coincide with record low levels in the abundance of pelagic organisms including phytoplankton, zooplankton, and fish. The potential negative impact of Microcystis on the copepods Eurytemora affinis and Pseudodiaptomus forbesi has raised concern for further depletion of high quality fish food. Response of copepods to MC-LR (MC) was determined using a 48-h standard static renewal method for acute toxicity testing. Following exposure, a life table test was performed to quantify any post-exposure impacts on survival and reproduction. The 48-h LC-50 and LC-10 values for MC were 1.55 and 0.14 mg/L for E. affinis; and 0.52 and 0.21 mg/L for P. forbesi. Copepod populations recovered once dissolved MC was removed and cultures returned to optimal conditions, suggesting no post-exposure effects of MC on copepod populations. Dissolved microcystin above 0.14 mg/L proved likely to have chronic effects on the survival of copepods in the SFE. Since such high concentrations are unlikely, toxicity from dissolved microcystin is not a direct threat to zooplankton of the SFE, and other mechanisms such as dietary exposure to Microcystis constitute a more severe risk.

Influence of application method on surface free-energy and bond strength of universal adhesive systems to enamel.

PubMed

Imai, Arisa; Takamizawa, Toshiki; Sai, Keiichi; Tsujimoto, Akimasa; Nojiri, Kie; Endo, Hajime; Barkmeier, Wayne W; Latta, Mark A; Miyazaki, Masashi

2017-10-01

The aim of the present study was to determine the influence of different adhesive application methods and etching modes on enamel bond effectiveness of universal adhesives using shear bond strength (SBS) testing and surface free-energy (SFE) measurements. The adhesives Scotchbond Universal, All-Bond Universal, Adhese Universal, and G-Premio Bond were used. Prepared bovine enamel specimens were divided into four groups, based on type of adhesive, and subjected to the following surface treatments: (i) total-etch mode with active application; (ii) total-etch mode with inactive application; (iii) self-etch mode with active application; and (iv) self-etch mode with inactive application. Bonded specimens were subjected to SBS testing. The SFE of the enamel surfaces with adhesive was measured after rinsing with acetone and water. The SBS values in total-etch mode were significantly higher than those in self-etch mode. In total-etch mode, significantly lower SBS values were observed with active application compared with inactive application; in contrast, in self-etch mode there were no significant differences in SBS between active and inactive applications. A reduction in total SFE was observed for active application compared with inactive application. The interaction between etching mode and application method was statistically significant, and the application method significantly affected enamel bond strength in total-etch mode. © 2017 Eur J Oral Sci.

Discovery of Newer Therapeutic Leads for Prostate Cancer

DTIC Science & Technology

2009-06-01

promising plant extracts and then prepare large-scale quantities of the plant extracts using supercritical fluid extraction techniques and use this...quantities of the plant extracts using supercritical fluid extraction techniques. Large scale plant collections were conducted for 14 of the top 20...material for bioassay-guided fractionation of the biologically active constituents using modern chromatography techniques. The chemical structures of

Investigation of extractable organic compounds in deep-sea hydrothermal vent fluids along the Mid-Atlantic Ridge

NASA Astrophysics Data System (ADS)

McCollom, Thomas M.; Seewald, Jeffrey S.; German, Christopher R.

2015-05-01

The possibility that deep-sea hydrothermal vents may contain organic compounds produced by abiotic synthesis or by microbial communities living deep beneath the surface has led to numerous studies of the organic composition of vent fluids. Most of these studies have focused on methane and other light hydrocarbons, while the possible occurrence of more complex organic compounds in the fluids has remained largely unstudied. To address this issue, the presence of higher molecular weight organic compounds in deep-sea hydrothermal fluids was assessed at three sites along the Mid-Atlantic Ridge that span a range of temperatures (51 to >360 °C), fluid compositions, and host-rock lithologies (mafic to ultramafic). Samples were obtained at several sites within the Lucky Strike, Rainbow, and Lost City hydrothermal fields. Three methods were employed to extract organic compounds for analysis, including liquid:liquid extraction, cold trapping on the walls of a coil of titanium tubing, and pumping fluids through cartridges filled with solid phase extraction (SPE) sorbents. The only samples to consistently yield high amounts of extractable organic compounds were the warm (51-91 °C), highly alkaline fluids from Lost City, which contained elevated concentrations of C8, C10, and C12n-alkanoic acids and, in some cases, trithiolane, hexadecanol, squalene, and cholesterol. Collectively, the C8-C12 acids can account for about 15% of the total dissolved organic carbon in the Lost City fluids. The even-carbon-number predominance of the alkanoic acids indicates a biological origin, but it is unclear whether these compounds are derived from microbial activity occurring within the hydrothermal chimney proximal to the site of fluid discharge or are transported from deeper within the system. Hydrothermal fluids from the Lucky Strike and Rainbow fields were characterized by an overall scarcity of extractable dissolved organic compounds. Trace amounts of aromatic hydrocarbons including phenanthrenes and benzothiophene were the only compounds that could be identified as indigenous components of these fluids. Although hydrocarbons and fatty acids were observed in some samples, those compounds were likely derived from particulate matter or biomass entrained during fluid collection. In addition, extracts of some fluid samples from the Rainbow field were found to contain an unresolved complex mixture (UCM) of organic compounds. This UCM shared some characteristics with organic matter extracted from bottom seawater, suggesting that the organic matter observed in these samples might represent seawater-derived compounds that had persisted, albeit with partial alteration, during circulation through the hydrothermal system. While there is considerable evidence that Rainbow and Lost City vent fluids contain methane and other light hydrocarbons produced through abiotic reduction of inorganic carbon, we found no evidence for more complex organic compounds with an abiotic origin in the same fluids.

Determination of As concentration in earthworm coelomic fluid extracts by total-reflection X-ray fluorescence spectrometry

NASA Astrophysics Data System (ADS)

Allegretta, Ignazio; Porfido, Carlo; Panzarino, Onofrio; Fontanella, Maria Chiara; Beone, Gian Maria; Spagnuolo, Matteo; Terzano, Roberto

2017-04-01

Earthworms are often used as sentinel organisms to study As bioavailability in polluted soils. Arsenic in earthworms is mainly sequestrated in the coelomic fluids whose As content can therefore be used to asses As bioavalability. In this work, a method for determining As concentration in coelomic fluid extracts using total-reflection X-ray fluorescence spectrometry (TXRF) is presented. For this purpose coelomic fluid extracts from earthworms living in three polluted soils and one non-polluted (control) soil have been collected and analysed. A very simple sample preparation was implemented, consisting of a dilution of the extracts with polyvinyl alcohol (PVA) using a 1:8 ratio and dropwise deposition of the sample on the reflector. A detection limit of 0.2 μg/l and quantification limit of 0.6 μg/l was obtained in the diluted samples, corresponding to 2 μg/l and 6 μg/l in the coelomic fluid extracts, respectively. This allowed to quantify As concentration in coelomic fluids extracted from earthworms living in soils polluted with As at concentrations higher than 20 mg/kg (considered as a pollution threshold for agricultural soils). The TXRF method has been validated by comparison with As concentrations in standards and by analysing the same samples by ICP-MS, after acid digestion of the sample. The low limit of detection, the proven reliability of the method and the little sample preparation make TXRF a suitable, cost-efficient and "green" technique for the analysis of As in earthworm coelomic fluid extracts for bioavailability studies.

Precipitation Effect on Mechanical Properties and Phase Stability of High Manganese Steel

NASA Astrophysics Data System (ADS)

Bae, Cheoljun; Kim, Rosa; Lee, Un-Hae; Kim, Jongryoul

2017-09-01

High manganese (Mn) steels are attractive for automotive applications due to their excellent tensile strength and superior elongation. However, the relatively low yield strength of Mn steels compared to other advanced high-strength steels is a critical problem limiting their use in structural parts. In order to increase the yield strength, the precipitation hardening effect of Mn steels was investigated by the addition of carbide-forming elements. Changes in the austenite phase stability were also evaluated in terms of stacking fault energy (SFE). As a result, fine V(C,N) precipitates were found to increase the yield strength effectively but to lower the SFE by the consumption of matrix carbons. For achieving precipitation hardening without sacrificing austenite stability, the soluble carbon content was discussed.

ENGINEERING BULLETIN: IN SITU SOIL FLUSHING

EPA Science Inventory

In situ soil flushing is the extraction of contaminants from the soil with water or other suitable aqueous solutions. Soil flushing is accomplished by passing the extraction fluid through in-place soils using an injection or infiltration process. Extraction fluids must be recover...

Determination of the bioaccessible fraction of metals in urban aerosol using simulated lung fluids

NASA Astrophysics Data System (ADS)

Coufalík, Pavel; Mikuška, Pavel; Matoušek, Tomáš; Večeřa, Zbyněk

2016-09-01

Determination of the bioaccessible fraction of metals in atmospheric aerosol is a significant issue with respect to air pollution in the urban environment. The aim of this work was to compare of metal bioaccessibility determined according to the extraction yields of six simulated lung fluids. Aerosol samples of the PM1 fraction were collected in Brno, Czech Republic. The total contents of Cd, Ce, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn in the samples were determined and their enrichment factors were calculated. The bioaccessible proportions of elements were determined by means of extraction in Gamble's solution, Gamble's solution with dipalmitoyl phosphatidyl choline (DPPC), artificial lysosomal fluid, saline, water, and in a newly proposed solution based on DPPC, referred to as "Simulated Alveoli Fluid" (SAF). The chemical composition and surface tension of the simulated lung fluids were the main parameters influencing extraction yields. Gamble's solutions and the newly designed solution of SAF exhibited the lowest extraction efficiency, and also had the lowest surface tensions. The bioaccessibility of particulate metals should be assessed by synthetic lung fluids with a low surface tension, which simulate better the behavior and composition of native lung surfactant. The bioaccessibility of metals in aerosol assessed by means of the extraction in water or artificial lysosomal fluid can be overestimated.

Impact of a star formation efficiency profile on the evolution of open clusters

NASA Astrophysics Data System (ADS)

Shukirgaliyev, B.; Parmentier, G.; Berczik, P.; Just, A.

2017-09-01

Aims: We study the effect of the instantaneous expulsion of residual star-forming gas on star clusters in which the residual gas has a density profile that is shallower than that of the embedded cluster. This configuration is expected if star formation proceeds with a given star-formation efficiency per free-fall time in a centrally concentrated molecular gas clump. Methods: We performed direct N-body simulations whose initial conditions were generated by the program "mkhalo" from the package "falcON", adapted for our models. Our model clusters initially had a Plummer profile and are in virial equilibrium with the gravitational potential of the cluster-forming clump. The residual gas contribution was computed based on a local-density driven clustered star formation model. Our simulations included mass loss by stellar evolution and the tidal field of a host galaxy. Results: We find that a star cluster with a minimum global star formation efficiency (SFE) of 15 percent is able to survive instantaneous gas expulsion and to produce a bound cluster. Its violent relaxation lasts no longer than 20 Myr, independently of its global SFE and initial stellar mass. At the end of violent relaxation, the bound fractions of the surviving clusters with the same global SFEs are similar, regardless of their initial stellar mass. Their subsequent lifetime in the gravitational field of the Galaxy depends on their bound stellar masses. Conclusions: We therefore conclude that the critical SFE needed to produce a bound cluster is 15 percent, which is roughly half the earlier estimates of 33 percent. Thus we have improved the survival likelihood of young clusters after instantaneous gas expulsion. Young clusters can now survive instantaneous gas expulsion with a global SFEs as low as the SFEs observed for embedded clusters in the solar neighborhood (15-30 percent). The reason is that the star cluster density profile is steeper than that of the residual gas. However, in terms of the effective SFE, measured by the virial ratio of the cluster at gas expulsion, our results are in agreement with previous studies.

Fluid extraction

DOEpatents

Wai, Chien M.; Laintz, Kenneth E.

1999-01-01

A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a supercritical fluid solvent containing a chelating agent is described. The chelating agent forms chelates that are soluble in the supercritical fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is a fluorinated .beta.-diketone. In especially preferred embodiments the extraction solvent is supercritical carbon dioxide, and the chelating agent comprises a fluorinated .beta.-diketone and a trialkyl phosphate, or a fluorinated .beta.-diketone and a trialkylphosphine oxide. Although a trialkyl phosphate can extract lanthanides and actinides from acidic solutions, a binary mixture comprising a fluorinated .beta.-diketone and a trialkyl phosphate or a trialkylphosphine oxide tends to enhance the extraction efficiencies for actinides and lanthanides. The method provides an environmentally benign process for removing contaminants from industrial waste without using acids or biologically harmful solvents. The method is particularly useful for extracting actinides and lanthanides from acidic solutions. The chelate and supercritical fluid can be regenerated, and the contaminant species recovered, to provide an economic, efficient process.

The extraction of liquid, protein molecules and yeast cells from paper through surface acoustic wave atomization.

PubMed

Qi, Aisha; Yeo, Leslie; Friend, James; Ho, Jenny

2010-02-21

Paper has been proposed as an inexpensive and versatile carrier for microfluidics devices with abilities well beyond simple capillary action for pregnancy tests and the like. Unlike standard microfluidics devices, extracting a fluid from the paper is a challenge and a drawback to its broader use. Here, we extract fluid from narrow paper strips using surface acoustic wave (SAW) irradiation that subsequently atomizes the extracted fluid into a monodisperse aerosol for use in mass spectroscopy, medical diagnostics, and drug delivery applications. Two protein molecules, ovalbumin and bovine serum albumin (BSA), have been preserved in paper and then extracted using atomized mist through SAW excitation; protein electrophoresis shows there is less than 1% degradation of either protein molecule in this process. Finally, a solution of live yeast cells was infused into paper, which was subsequently dried for preservation then remoistened to extract the cells via SAW atomization, yielding live cells at the completion of the process. The successful preservation and extraction of fluids, proteins and yeast cells significantly expands the usefulness of paper in microfluidics.

Theoretical models for supercritical fluid extraction.

PubMed

Huang, Zhen; Shi, Xiao-Han; Jiang, Wei-Juan

2012-08-10

For the proper design of supercritical fluid extraction processes, it is essential to have a sound knowledge of the mass transfer mechanism of the extraction process and the appropriate mathematical representation. In this paper, the advances and applications of kinetic models for describing supercritical fluid extraction from various solid matrices have been presented. The theoretical models overviewed here include the hot ball diffusion, broken and intact cell, shrinking core and some relatively simple models. Mathematical representations of these models have been in detail interpreted as well as their assumptions, parameter identifications and application examples. Extraction process of the analyte solute from the solid matrix by means of supercritical fluid includes the dissolution of the analyte from the solid, the analyte diffusion in the matrix and its transport to the bulk supercritical fluid. Mechanisms involved in a mass transfer model are discussed in terms of external mass transfer resistance, internal mass transfer resistance, solute-solid interactions and axial dispersion. The correlations of the external mass transfer coefficient and axial dispersion coefficient with certain dimensionless numbers are also discussed. Among these models, the broken and intact cell model seems to be the most relevant mathematical model as it is able to provide realistic description of the plant material structure for better understanding the mass-transfer kinetics and thus it has been widely employed for modeling supercritical fluid extraction of natural matters. Copyright © 2012 Elsevier B.V. All rights reserved.

Cytotoxicity evaluation of Curcuma zedoaria (Christm.) Roscoe fluid extract used in oral hygiene products.

PubMed

Fernandes, Joao Paulo Dos Santos; Mello-Moura, Anna Carolina Volpi; Marques, Marcia Martins; Nicoletti, Maria Aparecida

2012-12-01

This in vitro study evaluated the cytotoxic effects of the Curcuma zedoaria (Christm.) Roscoe (popular name: zedoary) fluid extract, as used in preparations for oral hygiene, mostly for anti-septic purposes. The cell viability and cell growth were assessed by Trypan blue dye exclusion assay using the LMF cell line derived from oral mucosa. Cell viability (short-term assay) was measured 0, 6, 12 and 24 h after contact with the fluid extract. Cell growth (long-term assay) was analyzed in 1, 3, 5 and 7 days. The experimental groups were those testing the fluid extract obtained from the zedoary rhizome and the extractor liquid (ethanol 70° GL) in the concentrations of 0.01-0.0001% v/v. Fresh DMEM were used in the control cultures. Short-term assay-all studied cultures maintained stable cell viability; Long-term assay-there was progressive cell growth in all studied cultures. According to the results, the zedoary fluid extract presents low cytotoxicity and probably can be used in the oral hygiene products.

Supercritical fluid extraction and direct fluid injection mass spectrometry for the determination of trichothecene mycotoxins in wheat samples

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kalinoski, H.T.; Udseth, H.R.; Wright, B.W.

1986-10-01

The application of on-line supercritical fluid extraction with chemical ionization mass spectrometry and collision induced dissociation tandem mass spectrometry for the rapid identification of parts-per-million levels of several trichothecene mycotoxins is demonstrated. Supercritical carbon dioxide is shown to allow identification of mycotoxins with minimum sample handling in complex natural matrices (e.g., wheat). Tandem mass spectrometry techniques are employed for unambiguous identification of compounds of varying polarity, and false positives from isobaric compounds are avoided. Capillary column supercritical fluid chromatography-mass spectrometry of a supercritical fluid extract of the same sample was also performed and detection limits in the parts-per-billion range appearmore » feasible.« less

Bio-oil production from biomass via supercritical fluid extraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Durak, Halil, E-mail: halildurak@yyu.edu.tr

2016-04-18

Supercritical fluid extraction is used for producing bio-fuel from biomass. Supercritical fluid extraction process under supercritical conditions is the thermally disruption process of the lignocellulose or other organic materials at 250-400 °C temperature range under high pressure (4-5 MPa). Supercritical fluid extraction trials were performed in a cylindrical reactor (75 mL) in organic solvents (acetone, ethanol) under supercritical conditions with (calcium hydroxide, sodium carbonate) and without catalyst at the temperatures of 250, 275 and 300 °C. The produced liquids at 300 °C in supercritical liquefaction were analyzed and characterized by elemental, GC-MS and FT-IR. 36 and 37 different types of compounds weremore » identified by GC-MS obtained in acetone and ethanol respectively.« less

High-Temperature Lubricant Analyses Using the System for Thermal Diagnostic Studies (STDS). A Feasibility Study

DTIC Science & Technology

1990-07-01

permeation chromatography (GPC) have been applied to lubricant type samples. 8 Most recently the newly introduced supercritical fluid chromatography (SFC... fluids , such as lubricants and hydraulic fluids can also be examined using various inverse chromatography procedures. Another mode, known as reaction...introduction of new gaseous extraction techniques, e.g., supercritical fluid extraction, procedures such as IGC will probably be developed for vastly

STAR FORMATION ON SUBKILOPARSEC SCALE TRIGGERED BY NON-LINEAR PROCESSES IN NEARBY SPIRAL GALAXIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Momose, Rieko; Koda, Jin; Donovan Meyer, Jennifer

We report a super-linear correlation for the star formation law based on new CO(J = 1-0) data from the CARMA and NOBEYAMA Nearby-galaxies (CANON) CO survey. The sample includes 10 nearby spiral galaxies, in which structures at sub-kpc scales are spatially resolved. Combined with the star formation rate surface density traced by H{alpha} and 24 {mu}m images, CO(J = 1-0) data provide a super-linear slope of N = 1.3. The slope becomes even steeper (N = 1.8) when the diffuse stellar and dust background emission is subtracted from the H{alpha} and 24 {mu}m images. In contrast to the recent resultsmore » with CO(J = 2-1) that found a constant star formation efficiency (SFE) in many spiral galaxies, these results suggest that the SFE is not independent of environment, but increases with molecular gas surface density. We suggest that the excitation of CO(J = 2-1) is likely enhanced in the regions with higher star formation and does not linearly trace the molecular gas mass. In addition, the diffuse emission contaminates the SFE measurement most in regions where the star formation rate is law. These two effects can flatten the power-law correlation and produce the apparent linear slope. The super-linear slope from the CO(J = 1-0) analysis indicates that star formation is enhanced by non-linear processes in regions of high gas density, e.g., gravitational collapse and cloud-cloud collisions.« less

Effect of plantar intrinsic muscle training on medial longitudinal arch morphology and dynamic function.

PubMed

Mulligan, Edward P; Cook, Patrick G

2013-10-01

A specific training program emphasizing the neuromuscular recruitment of the plantar intrinsic foot muscles, colloquially referred to as "short foot" exercise (SFE) training, has been suggested as a means to dynamically support the medial longitudinal arch (MLA) during functional tasks. A single-group repeated measures pre- and post-intervention study design was utilized to determine if a 4-week intrinsic foot muscle training program would impact the amount of navicular drop (ND), increase the arch height index (AHI), improve performance during a unilateral functional reaching maneuver, or the qualitative assessment of the ability to hold the arch position in single limb stance position in an asymptomatic cohort. 21 asymptomatic subjects (42 feet) completed the 4-week SFE training program. Subject ND decreased by a mean of 1.8 mm at 4 weeks and 2.2 mm at 8 weeks (p < 0.05). AHI increased from 28 to 29% (p < 0.05). Intrinsic foot muscle performance during a static unilateral balancing activity improved from a grade of fair to good (p < 0.001) and subjects experienced a significant improvement during a functional balance and reach task in all directions with the exception of an anterior reach (p < 0.05). This study offers preliminary evidence to suggest that SFE training may have value in statically and dynamically supporting the MLA. Further research regarding the value of this exercise intervention in foot posture type or pathology specific patient populations is warranted. Copyright © 2013 Elsevier Ltd. All rights reserved.

Comparative short-term in vitro analysis of mutans streptococci adhesion on esthetic, nickel-titanium, and stainless-steel arch wires.

PubMed

Kim, In-Hye; Park, Hyo-Sang; Kim, Young Kyung; Kim, Kyo-Han; Kwon, Tae-Yub

2014-07-01

To test the hypothesis that there are no differences in mutans streptococci (MS) adhesion between esthetic and metallic orthodontic arch wires based on their surface characteristics. Surface roughness (Ra) and apparent surface free energy (SFE) were measured for six wires-four esthetic, one nickel-titanium (NiTi), and one stainless-steel (SS)-using profilometry and dynamic contact angle analysis, respectively. The amount of MS (Streptococcus mutans and Streptococcus sobrinus) adhering to the wires was quantified using the colony-counting method. The surfaces, coating layers, and MS adhesion were also observed by scanning electron microscopy. Statistical significance was set at P < .05. The Ra values of the esthetic wires were significantly different from one another depending on the coating method (P < .05). The NiTi wire showed the highest SFE, followed by the SS wire and then the four esthetic wires. The NiTi wires produced a significantly higher MS adhesion than did the SS wires (P < .05). The esthetic wires showed significantly lower MS adhesions than did the NiTi wire (P < .05). Pearson correlation analyses found moderate significant positive correlations between the SFE and the S mutans and S sobrinus adhesions (r  =  .636/.427, P < .001/P  =  .001, respectively). The hypothesis is rejected. This study indicates that some esthetic coatings on NiTi alloy might reduce MS adhesion in vitro in the short term.

Supercritical fluid extraction

DOEpatents

Wai, Chien M.; Laintz, Kenneth

1994-01-01

A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a supercritical fluid solvent containing a chelating agent. The chelating agent forms chelates that are soluble in the supercritical fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is a fluorinated or lipophilic crown ether or fluorinated dithiocarbamate. The method provides an environmentally benign process for removing contaminants from industrial waste without using acids or biologically harmful solvents. The chelate and supercritical fluid can be regenerated, and the contaminant species recovered, to provide an economic, efficient process.

21 CFR 310.531 - Drug products containing active ingredients offered over-the-counter (OTC) for the treatment of...

Code of Federal Regulations, 2013 CFR

2013-04-01

... subnitrate, calomel, camphor, cholesterol, ergot fluid extract, hexachlorophene, ichthammol, isobutamben... aminacrine hydrochloride, bismuth subnitrate, calomel, camphor, cholesterol, ergot fluid extract...

21 CFR 310.531 - Drug products containing active ingredients offered over-the-counter (OTC) for the treatment of...

Code of Federal Regulations, 2011 CFR

2011-04-01

... subnitrate, calomel, camphor, cholesterol, ergot fluid extract, hexachlorophene, ichthammol, isobutamben... aminacrine hydrochloride, bismuth subnitrate, calomel, camphor, cholesterol, ergot fluid extract...

21 CFR 310.531 - Drug products containing active ingredients offered over-the-counter (OTC) for the treatment of...

Code of Federal Regulations, 2010 CFR

2010-04-01

... subnitrate, calomel, camphor, cholesterol, ergot fluid extract, hexachlorophene, ichthammol, isobutamben... aminacrine hydrochloride, bismuth subnitrate, calomel, camphor, cholesterol, ergot fluid extract...

21 CFR 310.531 - Drug products containing active ingredients offered over-the-counter (OTC) for the treatment of...

Code of Federal Regulations, 2012 CFR

2012-04-01

... subnitrate, calomel, camphor, cholesterol, ergot fluid extract, hexachlorophene, ichthammol, isobutamben... aminacrine hydrochloride, bismuth subnitrate, calomel, camphor, cholesterol, ergot fluid extract...

21 CFR 310.531 - Drug products containing active ingredients offered over-the-counter (OTC) for the treatment of...

Code of Federal Regulations, 2014 CFR

2014-04-01

... subnitrate, calomel, camphor, cholesterol, ergot fluid extract, hexachlorophene, ichthammol, isobutamben... aminacrine hydrochloride, bismuth subnitrate, calomel, camphor, cholesterol, ergot fluid extract...

Digestive solubilization of sediment-associated pollutants: In vitro extraction vs. in vivo bioavailability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weston, D.P.; Mayer, L.M.

1995-12-31

A method using polychaete digestive fluids as a more biologically realistic extractant has recent been proposed as a means to quantify this bioavailable fraction. This work was intended to evaluate this approach with polynuclear aromatic hydrocarbons (PAH), and, in particular, to relate in vitro measures of PAH solubilization by digestive fluids to bioavailability as perceived by the whole animal. In tests with a variety of PAH-contaminated sediments, there were dramatic differences among the sediments in the amounts of PAH extracted by digestive fluids. About 50% of a PAH spike was extracted from a low organic carbon sediment during digestive fluidmore » extraction, while only 20% was extracted from a high organic carbon sediment. The relationships between these differences in PAH solubilization and true bioavailability were evaluated in polychaete bioaccumulation tests measuring PAH uptake rate coefficients and steady state body burdens. The work has also shown that desorption of PAH from ingested sediments in the whole animal approximated the quantities extracted in the in vitro tests. Moreover, desorption of PAH from ingested sediments was found to be greatest in that portion of the polychaete gut with the highest enzymatic activity and from which the digestive fluids had been collected. The digestive fluid extraction approach provides a new tool to examine digestive uptake of contaminants by manipulations that would be impossible in vivo, and may help to quantify a bioavailable contaminant fraction.« less

ECLSS evolution: Advanced instrumentation interface requirements. Volume 3: Appendix C

NASA Technical Reports Server (NTRS)

1991-01-01

An Advanced ECLSS (Environmental Control and Life Support System) Technology Interfaces Database was developed primarily to provide ECLSS analysts with a centralized and portable source of ECLSS technologies interface requirements data. The database contains 20 technologies which were previously identified in the MDSSC ECLSS Technologies database. The primary interfaces of interest in this database are fluid, electrical, data/control interfaces, and resupply requirements. Each record contains fields describing the function and operation of the technology. Fields include: an interface diagram, description applicable design points and operating ranges, and an explaination of data, as required. A complete set of data was entered for six of the twenty components including Solid Amine Water Desorbed (SAWD), Thermoelectric Integrated Membrane Evaporation System (TIMES), Electrochemical Carbon Dioxide Concentrator (EDC), Solid Polymer Electrolysis (SPE), Static Feed Electrolysis (SFE), and BOSCH. Additional data was collected for Reverse Osmosis Water Reclaimation-Potable (ROWRP), Reverse Osmosis Water Reclaimation-Hygiene (ROWRH), Static Feed Solid Polymer Electrolyte (SFSPE), Trace Contaminant Control System (TCCS), and Multifiltration Water Reclamation - Hygiene (MFWRH). A summary of the database contents is presented in this report.

Extraction of metals and/or metalloids from acidic media using supercritical fluids and salts

DOEpatents

Wai, Chien M.; Smart, Neil G.; Lin, Yuehe

1998-01-01

A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a fluid solvent, particularly supercritical carbon dioxide, containing a chelating agent is described. The chelating agent forms chelates that are soluble in the fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent comprises a trialkyl phosphate, a triaryl phosphate, a trialkylphosphine oxide, a triarylphosphine oxide, or mixtures thereof. The method provides an environmentally benign process for removing contaminants from industrial waste. The method is particularly useful for extracting actinides from acidic solutions, and the process can be aided by the addition of nitrate salts. The chelate and supercritical fluid can be regenerated, and the contaminant species recovered, to provide an economic, efficient process.

Extraction of metals using supercritical fluid and chelate forming legand

DOEpatents

Wai, Chien M.; Laintz, Kenneth E.

1998-01-01

A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a supercritical fluid solvent containing a chelating agent is described. The chelating agent forms chelates that are soluble in the supercritical fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is a fluorinated .beta.-diketone. In especially preferred embodiments the extraction solvent is supercritical carbon dioxide, and the chelating agent comprises a fluorinated .beta.-diketone and a trialkyl phosphate, or a fluorinated .beta.-diketone and a trialkylphosphine oxide. Although a trialkyl phosphate can extract lanthanides and actinides from acidic solutions, a binary mixture comprising a fluorinated .beta.-diketone and a trialkyl phosphate or a trialkylphosphine oxide tends to enhance the extraction efficiencies for actinides and lanthanides. The method provides an environmentally benign process for removing contaminants from industrial waste without using acids or biologically harmful solvents. The method is particularly useful for extracting actinides and lanthanides from acidic solutions. The chelate and supercritical fluid can be regenerated, and the contaminant species recovered, to provide an economic, efficient process.

Extraction of metals using supercritical fluid and chelate forming ligand

DOEpatents

Wai, C.M.; Laintz, K.E.

1998-03-24

A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a supercritical fluid solvent containing a chelating agent is described. The chelating agent forms chelates that are soluble in the supercritical fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is a fluorinated {beta}-diketone. In especially preferred embodiments the extraction solvent is supercritical carbon dioxide, and the chelating agent comprises a fluorinated {beta}-diketone and a trialkyl phosphate, or a fluorinated {beta}-diketone and a trialkylphosphine oxide. Although a trialkyl phosphate can extract lanthanides and actinides from acidic solutions, a binary mixture comprising a fluorinated {beta}-diketone and a trialkyl phosphate or a trialkylphosphine oxide tends to enhance the extraction efficiencies for actinides and lanthanides. The method provides an environmentally benign process for removing contaminants from industrial waste without using acids or biologically harmful solvents. The method is particularly useful for extracting actinides and lanthanides from acidic solutions. The chelate and supercritical fluid can be regenerated, and the contaminant species recovered, to provide an economic, efficient process. 7 figs.

Noble gases fingerprint a metasedimentary fluid source in the Macraes orogenic gold deposit, New Zealand

NASA Astrophysics Data System (ADS)

Goodwin, Nicholas R. J.; Burgess, Ray; Craw, Dave; Teagle, Damon A. H.; Ballentine, Chris J.

2017-02-01

The world-class Macraes orogenic gold deposit (˜10 Moz resource) formed during the late metamorphic uplift of a metasedimentary schist belt in southern New Zealand. Mineralising fluids, metals and metalloids were derived from within the metasedimentary host. Helium and argon extracted from fluid inclusions in sulphide mineral grains (three crush extractions from one sample) have crustal signatures, with no evidence for mantle input (R/Ra = 0.03). Xenon extracted from mineralised quartz samples provides evidence for extensive interaction between fluid and maturing organic material within the metasedimentary host rocks, with 132Xe/36Ar ratios up to 200 times greater than air. Similarly, I/Cl ratios for fluids extracted from mineralised quartz are similar to those of brines from marine sediments that have interacted with organic matter and are ten times higher than typical magmatic/mantle fluids. The Macraes mineralising fluids were compositionally variable, reflecting either mixing of two different crustal fluids in the metasedimentary pile or a single fluid type that has had varying degrees of interaction with the host metasediments. Evidence for additional input of meteoric water is equivocal, but minor meteoric incursion cannot be discounted. The Macraes deposit formed in a metasedimentary belt without associated coeval magmatism, and therefore represents a purely crustal metamorphogenic end member in a spectrum of orogenic hydrothermal processes that can include magmatic and/or mantle fluid input elsewhere in the world. There is no evidence for involvement of minor intercalated metabasic rocks in the Macraes mineralising system. Hydrothermal fluids that formed other, smaller, orogenic deposits in the same metamorphic belt have less pronounced noble gas and halogen evidence for crustal fluid-rock interaction than at Macraes, but these deposits also formed from broadly similar metamorphogenic processes.

On the chemical composition of L-chondrites

NASA Technical Reports Server (NTRS)

Neal, C. W.; Dodd, R. T.; Jarosewich, E.; Lipschutz, M. E.

1980-01-01

Radiochemical neutron activation analysis of Ag, As, Au, Bi, Co, Cs, Ga, In, Rb, Sb, Te, Tl, and Zn and major element data in 14 L4-6 and 3 LL5 chondrites indicates that the L group is unusually variable and may represent at least 2 subgroups differing in formation history. Chemical trends in the S/Fe rich subgroup support textural evidence indicating late loss of a shock formed Fe-Ni-S melt; the S/Fe poor subgroup seemingly reflects nebular fractionation only. Highly mobile In and Zn apparently reflect shock induced loss from L chondrites. However, contrasting chemical trends in several L chondrite sample sets indicate that these meteorites constitute a more irregular sampling of, or more heterogeneous parent material than do carbonaceous or enstatite chondrites. Data for 15 chondrites suggest higher formation temperatures and/or degrees of shock than for LL5 chondrites.

Mitigating fluorescence spectral overlap in wide-field endoscopic imaging

PubMed Central

Hou, Vivian; Nelson, Leonard Y.; Seibel, Eric J.

2013-01-01

Abstract. The number of molecular species suitable for multispectral fluorescence imaging is limited due to the overlap of the emission spectra of indicator fluorophores, e.g., dyes and nanoparticles. To remove fluorophore emission cross-talk in wide-field multispectral fluorescence molecular imaging, we evaluate three different solutions: (1) image stitching, (2) concurrent imaging with cross-talk ratio subtraction algorithm, and (3) frame-sequential imaging. A phantom with fluorophore emission cross-talk is fabricated, and a 1.2-mm ultrathin scanning fiber endoscope (SFE) is used to test and compare these approaches. Results show that fluorophore emission cross-talk could be successfully avoided or significantly reduced. Near term, the concurrent imaging method of wide-field multispectral fluorescence SFE is viable for early stage cancer detection and localization in vivo. Furthermore, a means to enhance exogenous fluorescence target-to-background ratio by the reduction of tissue autofluorescence background is demonstrated. PMID:23966226

Effect of natural ageing on surface of silver loaded TPE and its influence in antimicrobial efficacy

NASA Astrophysics Data System (ADS)

Tomacheski, Daiane; Pittol, Michele; Simões, Douglas Naue; Ribeiro, Vanda Ferreira; Santana, Ruth Marlene Campomanes

2017-05-01

The aim of this study is to characterize the modifications in silver loaded TPE surfaces exposed to weathering and their relation to susceptibility to microbial attack. Silver loaded TPE materials were exposed to natural ageing for nine months and modifications in antimicrobial properties and surface characteristics were evaluated. Chemical changes were investigated by using the infrared spectra. The average surface roughness and topography were determined by atomic force microscopy. Contact angle was measured to verify wettability conditions and surface free energy (SFE). After nine months of exposure, a decrease in the antimicrobial properties of loaded TPE compounds was observed. A reduction in surface roughness and improvement in wettability and high values of polar component of SFE were verified. The best antibacterial action was noticed in the sample with high Lewis acid force, lower roughness and lower carbonyl index.

32 CFR 634.38 - Involuntary extraction of bodily fluids in traffic cases.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 4 2010-07-01 2010-07-01 true Involuntary extraction of bodily fluids in traffic cases. 634.38 Section 634.38 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) LAW ENFORCEMENT AND CRIMINAL INVESTIGATIONS MOTOR VEHICLE TRAFFIC SUPERVISION Traffic Supervision § 634.38 Involuntary extraction of...

Turbo Pump Fed Micro-Rocket Engine

NASA Astrophysics Data System (ADS)

Miotti, P.; Tajmar, M.; Seco, F.; Guraya, C.; Perennes, F.; Soldati, A.; Lang, M.

2004-10-01

Micro-satellites (from 10kg up to 100kg) have mass, volume, and electrical power constraints due to their low dimensions. These limitations lead to the lack in currently available active orbit control systems in micro-satellites. Therefore, a micro-propulsion system with a high thrust to mass ratio is required to increase the potential functionality of small satellites. Mechatronic is presently working on a liquid bipropellant micro-rocket engine under contract with ESA (Contract No.16914/NL/Sfe - Micro-turbo-machinery Based Bipropellant System Using MNT). The advances in Mechatronic's project are to realise a micro-rocket engine with propellants pressurised by micro-pumps. The energy for driving the pumps would be extracted from a micro-turbine. Cooling channels around the nozzle would be also used in order to maintain the wall material below its maximum operating temperature. A mass budget comparison with more traditional pressure-fed micro-rockets shows a real benefit from this system in terms of mass reduction. In the paper, an overview of the project status in Mechatronic is presented.

Extraction of metals and/or metalloids from acidic media using supercritical fluids and salts

DOEpatents

Wai, C.M.; Smart, N.G.; Lin, Y.

1998-06-23

A method is described for extracting metalloid and metal species from a solid or liquid material by exposing the material to a fluid solvent, particularly supercritical carbon dioxide, containing a chelating agent. The chelating agent forms chelates that are soluble in the fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent comprises a trialkyl phosphate, a triaryl phosphate, a trialkylphosphine oxide, a triarylphosphine oxide, or mixtures thereof. The method provides an environmentally benign process for removing contaminants from industrial waste. The method is particularly useful for extracting actinides from acidic solutions, and the process can be aided by the addition of nitrate salts. The chelate and supercritical fluid can be regenerated, and the contaminant species recovered, to provide an economic, efficient process. 7 figs.

Systems and methods for multi-fluid geothermal energy systems

DOEpatents

Buscheck, Thomas A.

2017-09-19

A method for extracting geothermal energy from a geothermal reservoir formation. A production well is used to extract brine from the reservoir formation. At least one of nitrogen (N.sub.2) and carbon dioxide (CO.sub.2) may be used to form a supplemental working fluid which may be injected into a supplemental working fluid injection well. The supplemental working fluid may be used to augment a pressure of the reservoir formation, to thus drive a flow of the brine out from the reservoir formation.

Measurement of polychlorinated biphenyls in solid waste such as transformer insulation paper by supercritical fluid extraction and gas chromatography electron capture detection.

PubMed

Chikushi, Hiroaki; Fujii, Yuka; Toda, Kei

2012-09-21

In this work, a method for measuring polychlorinated biphenyls (PCBs) in contaminated solid waste was investigated. This waste includes paper that is used in electric transformers to insulate electric components. The PCBs in paper sample were extracted by supercritical fluid extraction and analyzed by gas chromatography-electron capture detection. The recoveries with this method (84-101%) were much higher than those with conventional water extraction (0.08-14%), and were comparable to those with conventional organic solvent extraction. Limit of detection was 0.0074 mg kg(-1) and measurable up to 2.5 mg kg(-1) for 0.5 g of paper sample. Data for real insulation paper by the proposed method agreed well with those by the conventional organic solvent extraction. Extraction from wood and concrete was also investigated and good performance was obtained as well as for paper samples. The supercritical fluid extraction is simpler, faster, and greener than conventional organic solvent extraction. Copyright © 2012 Elsevier B.V. All rights reserved.

Improving patient and user safety during endoscopic investigation of the pancreatic and biliary ducts

NASA Astrophysics Data System (ADS)

Chandler, John E.; Melville, C. David; Lee, Cameron M.; Saunders, Michael D.; Burkhardt, Matthew R.; Seibel, Eric J.

2011-03-01

Endoscopic investigation of the main pancreatic duct and biliary ducts is called endoscopic retrograde cholangiopancreatography (ERCP), and carries a risk of pancreatitis for the patient. During ERCP, a metal guidewire is inserted into the pancreatobiliary duct from a side-viewing large endoscope within the duodenum. To verify correct placement of the ERCP guidewire, an injection of radiopaque dye is required for fluoroscopic imaging, which exposes the patient and clinical team to x-ray radiation. A safer and more effective means to access the pancreatobiliary system can use direct optical imaging, although the endoscope diameter and stiffness will be significantly larger than a guidewire's. To quantify this invasiveness before human testing, a synthetic force-sensing pancreas was fabricated and attached to an ERCP training model. The invasiveness of a new, 1.7-mm diameter, steerable scanning fiber endoscope (SFE) was compared to the standard ERCP guidewire of 0.89-mm (0.035") diameter that is not steerable. Although twice as large and significantly stiffer than the ERCP guidewire, the SFE generated lower or significantly less average force during insertion at all 4 sensor locations (P<0.05) within the main pancreatic duct. Therefore, the addition of steering and forward visualization at the tip of the endoscope reduced the invasiveness of the in vitro ERCP procedure. Since fluoroscopy is not required, risks associated with dye injection and x-ray exposure can be eliminated when using direct optical visualization. Finally, the SFE provides wide-field high resolution imaging for image-guided interventions, laser-based fluorescence biomarker imaging, and spot spectral analysis for future optical biopsy.

Image-guided intervention in the human bile duct using scanning fiber endoscope system

NASA Astrophysics Data System (ADS)

Seibel, Eric J.; Jo, Javier A.; Melville, C. David; Johnston, Richard S.; Naumann, Christopher R.; Saunders, Michael D.

2012-01-01

Bile duct cancers are increasing in frequency while being difficult to diagnose. Currently available endoscopic imaging devices used in the biliary tree are low resolution with poor image quality, leading to inadequate evaluation of indeterminate biliary strictures. However, a new ultrathin and flexible cholangioscope system has been successfully demonstrated in a human subject. This mini-cholangioscope system uses a scanning fiber endoscope (SFE) as a forward-imaging guidewire, dimensions of 1.2-mm diameter and 3-m length. Full color video (500-line resolution at 30Hz) is the standard SFE imaging mode using spiral scanning of red, green, and blue laser light at low power. Image-guided operation of the biopsy forceps was demonstrated in healthy human bile ducts with and without saline flushing. The laser-based video imaging can be switched to various modes to enhance tissue markers of disease, such as widefield fluorescence and enhanced spectral imaging. In parallel work, biochemical discrimination of tissue health in pig bile duct has been accomplished using fiberoptic delivery of pulsed UV illumination and time-resolved autofluorescence spectroscopic measurements. Implementation of time-resolved fluorescence spectroscopy for biochemical assessment of the bile duct wall is being done through a secondary endoscopic channel. Preliminary results indicate that adequate SNR levels (> 30 dB) can be achieved through a 50 micron fiber, which could serve as an optical biopsy probe. The SFE is an ideal mini-cholangioscope for integration of both tissue and molecular specific image contrast in the future. This will provide the physician with unprecedented abilities to target biopsy locations and perform endoscopically-guided therapies.

Pore Fluid Extraction by Reactive Solitary Waves in 3-D

NASA Astrophysics Data System (ADS)

Omlin, Samuel; Malvoisin, Benjamin; Podladchikov, Yury Y.

2017-09-01

In the lower crust, viscous compaction is known to produce solitary porosity and fluid pressure waves. Metamorphic (de)volatilization reactions can also induce porosity changes in response to the propagating fluid pressure anomalies. Here we present results from high-resolution simulations using Graphic Processing Unit parallel processing with a model that includes both viscous (de)compaction and reaction-induced porosity changes. Reactive porosity waves propagate in a manner similar to viscous porosity waves, but through a different mechanism involving fluid release and trap in the solid by reaction. These waves self-generate from red noise or an ellipsoidal porosity anomaly with the same characteristic size and abandon their source region to propagate at constant velocity. Two waves traveling at different velocities pass through each other in a soliton-like fashion. Reactive porosity waves thus provide an additional mechanism for fluid extraction at shallow depths with implications for ore formation, diagenesis, metamorphic veins formation, and fluid extraction from subduction zones.

Systemic fat embolism and the patent foramen ovale--a prospective autopsy study.

PubMed

Nikolić, Slobodan; Zivković, Vladimir; Babić, Dragan; Djonić, Danijela; Djurić, Marija

2012-05-01

A fat embolism is a known and common complication of blunt force injuries, especially pelvic and long bones fractures. The aim of this study was to determine the importance of a patent foramen ovale (PFO) in developing systemic fat embolism (SFE) and eventually fat embolism syndrome (FES) in patients suffering from orthopaedic blunt injuries and consequent lung fat embolism. The sample was divided: 32 subjects with a sealed foramen ovale (SFO), and 20 subjects with a PFO. In our sample, there was no difference in either the incidence of renal fat embolism in subjects with PFO compared to those with SFO (Fisher's exact test 0.228, p=0.154) or in the grade of renal fat embolism (Pearson Chi-square 2.728, p=0.435). However, there was a statistically significant correlation between the grade of lung fat embolism and the number of fractured bones for the whole sample (Spearman's rho 0.271, p=0.052), but no correlation between the grade of lung fat embolism and the ISS or NISS (Pearson correlation 0.048, p=0.736, and 0.108, p=0.445, respectively). In our study, the presence of fat emboli in the kidney, i.e. SFE, could effectively be predicted by the grade of lung fat embolism (the moderate and slight grades of lung fat embolism were better predictors than the massive one: logistic regression - Wald. Coeff.=11.446, p=0.003, Wald. Coeff.=10.553, p=0.001, and Wald. Coeff.=4.128, p=0.042), and less effectively by presence of PFO (Wald. Coeff.=2.850, p=0.091). This study pointed out that lung and SFE are not pure biomechanical events, so the role of a PFO is not crucial in developing a lung fat embolism into a systemic embolism: the fat embolism is more of a biochemical and pathophsyiological event, than a biomechanical one. The appearance of a patent foramen ovale associated with a systemic fat embolism should be less emphasised: maybe arteriovenous shunts and anastomosis between the functional and nutritive, i.e. systemic circulation of lungs play a more important role in developing a SFE than a PFO. Copyright © 2010 Elsevier Ltd. All rights reserved.

Antioxidant effects of supercritical fluid garlic extracts in sunflower oil.

PubMed

Bravi, Elisabetta; Perretti, Giuseppe; Falconi, Caterina; Marconi, Ombretta; Fantozzi, Paolo

2017-01-01

Lipid oxidation causes changes in quality attributes of vegetable oils. Synthetic antioxidants have been used to preserve oils; however, there is interest in replacing them with natural ones. Garlic and its thiosulfinate compound allicin are known for their antioxidant activities. This study assesses a novel formulation, the supercritical fluid extract of garlic, on sunflower oil oxidation during an accelerated shelf-life test. Three quality parameters (free acidity, peroxide values, and p-anisidine values) were evaluated in each of the six oil samples. The samples included sunflower oil alone, sunflower oil supplemented with BHT, the undiluted supercritical fluid extract of garlic, and sunflower oils supplemented with three levels of garlic extract. The oils were also investigated for their antioxidant properties using the DPPH and the FRAP assays. The results were compared with the effect of the synthetic BHT. Our results underlined that the highest level of garlic extract may be superior, or at least comparable, with BHT in preserving sunflower oil. The oxidative degradation of oily samples can be limited by using supercritical fluid extract of garlic as it is a safe and an effective natural antioxidant formulation. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Quantitative determination of methamphetamine in oral fluid by liquid-liquid extraction and gas chromatography/mass spectrometry.

PubMed

Bahmanabadi, L; Akhgari, M; Jokar, F; Sadeghi, H B

2017-02-01

Methamphetamine abuse is one of the most medical and social problems many countries face. In spite of the ban on the use of methamphetamine, it is widely available in Iran's drug black market. There are many analytical methods for the detection of methamphetamine in biological specimen. Oral fluid has become a popular specimen to test for the presence of methamphetamine. The purpose of the present study was to develop a method for the extraction and detection of methamphetamine in oral fluid samples using liquid-liquid extraction (LLE) and gas chromatography/mass spectrometry (GC/MS) methods. An analytical study was designed in that blank and 50 authentic oral fluid samples were collected to be first extracted by LLE and subsequently analysed by GC/MS. The method was fully validated and showed an excellent intra- and inter-assay precision (reflex sympathetic dystrophy ˂ 10%) for external quality control samples. Recovery with LLE methods was 96%. Limit of detection and limit of quantitation were 5 and 15 ng/mL, respectively. The method showed high selectivity, no additional peak due to interfering substances in samples was observed. The introduced method was sensitive, accurate and precise enough for the extraction of methamphetamine from oral fluid samples in forensic toxicology laboratories.

Recovery of Oil with Unsaturated Fatty Acids and Polyphenols from Chaenomelessinensis (Thouin) Koehne: Process Optimization of Pilot-Scale Subcritical Fluid Assisted Extraction.

PubMed

Zhu, Zhenzhou; Zhang, Rui; Zhan, Shaoying; He, Jingren; Barba, Francisco J; Cravotto, Giancarlo; Wu, Weizhong; Li, Shuyi

2017-10-22

The potential effects of three modern extraction technologies (cold-pressing, microwaves and subcritical fluids) on the recovery of oil from Chaenomelessinensis (Thouin) Koehne seeds have been evaluated and compared to those of conventional chemical extraction methods (Soxhlet extraction). This oil contains unsaturated fatty acids and polyphenols. Subcritical fluid extraction (SbFE) provided the highest yield-25.79 g oil/100 g dry seeds-of the three methods. Moreover, the fatty acid composition in the oil samples was analysed using gas chromatography-mass spectrometry. This analysis showed that the percentages of monounsaturated (46.61%), and polyunsaturated fatty acids (42.14%), after applying SbFE were higher than those obtained by Soxhlet, cold-pressing or microwave-assisted extraction. In addition, the oil obtained under optimized SbFE conditions (35 min extraction at 35 °C with four extraction cycles), showed significant polyphenol (527.36 mg GAE/kg oil), and flavonoid (15.32 mg RE/kg oil), content, had a good appearance and was of high quality.

Fluid sampling system for a nuclear reactor

DOEpatents

Lau, Louis K.; Alper, Naum I.

1994-01-01

A system of extracting fluid samples, either liquid or gas, from the interior of a nuclear reactor containment utilizes a jet pump. To extract the sample fluid, a nonradioactive motive fluid is forced through the inlet and discharge ports of a jet pump located outside the containment, creating a suction that draws the sample fluid from the containment through a sample conduit connected to the pump suction port. The mixture of motive fluid and sample fluid is discharged through a return conduit to the interior of the containment. The jet pump and means for removing a portion of the sample fluid from the sample conduit can be located in a shielded sample grab station located next to the containment. A non-nuclear grade active pump can be located outside the grab sampling station and the containment to pump the nonradioactive motive fluid through the jet pump.

Fluid sampling system for a nuclear reactor

DOEpatents

Lau, L.K.; Alper, N.I.

1994-11-22

A system of extracting fluid samples, either liquid or gas, from the interior of a nuclear reactor containment utilizes a jet pump. To extract the sample fluid, a nonradioactive motive fluid is forced through the inlet and discharge ports of a jet pump located outside the containment, creating a suction that draws the sample fluid from the containment through a sample conduit connected to the pump suction port. The mixture of motive fluid and sample fluid is discharged through a return conduit to the interior of the containment. The jet pump and means for removing a portion of the sample fluid from the sample conduit can be located in a shielded sample grab station located next to the containment. A non-nuclear grade active pump can be located outside the grab sampling station and the containment to pump the nonradioactive motive fluid through the jet pump. 1 fig.

Automated Fluid Feature Extraction from Transient Simulations

NASA Technical Reports Server (NTRS)

Haimes, Robert; Lovely, David

1999-01-01

In the past, feature extraction and identification were interesting concepts, but not required to understand the underlying physics of a steady flow field. This is because the results of the more traditional tools like iso-surfaces, cuts and streamlines were more interactive and easily abstracted so they could be represented to the investigator. These tools worked and properly conveyed the collected information at the expense of much interaction. For unsteady flow-fields, the investigator does not have the luxury of spending time scanning only one "snap-shot" of the simulation. Automated assistance is required in pointing out areas of potential interest contained within the flow. This must not require a heavy compute burden (the visualization should not significantly slow down the solution procedure for co-processing environments like pV3). And methods must be developed to abstract the feature and display it in a manner that physically makes sense. The following is a list of the important physical phenomena found in transient (and steady-state) fluid flow: (1) Shocks, (2) Vortex cores, (3) Regions of recirculation, (4) Boundary layers, (5) Wakes. Three papers and an initial specification for the (The Fluid eXtraction tool kit) FX Programmer's guide were included. The papers, submitted to the AIAA Computational Fluid Dynamics Conference, are entitled : (1) Using Residence Time for the Extraction of Recirculation Regions, (2) Shock Detection from Computational Fluid Dynamics results and (3) On the Velocity Gradient Tensor and Fluid Feature Extraction.

Determination of gas volume trapped in a closed fluid system

NASA Technical Reports Server (NTRS)

Hunter, W. F.; Jolley, J. E.

1971-01-01

Technique involves extracting known volume of fluid and measuring system before and after extraction, volume of entrapped gas is then computed. Formula derived from ideal gas laws is basis of this method. Technique is applicable to thermodynamic cycles and hydraulic systems.

Pressurised fluid extraction of bupirimate and ethirimol from aged soils.

PubMed

Fitzpatrick, L J; Dean, J R

2001-05-25

This paper assesses the effect of pressurised fluid extraction (PFE) on the recovery of bupirimate and its degradation product, ethirimol from a range of soil types. The analytes were extracted under standard conditions (pressure, 2000 p.s.i.; temperature, 100 degrees C; and, three static flush cycles of 5 min static extraction time each) using a variety of individual and combined solvents. It was found that the recovery of bupirimate was dependent upon the organic matter content of soil.

Submersible pumping system with heat transfer mechanism

DOEpatents

Hunt, Daniel Francis Alan; Prenger, F. Coyne; Hill, Dallas D; Jankowski, Todd Andrew

2014-04-15

A submersible pumping system for downhole use in extracting fluids containing hydrocarbons from a well. In one embodiment, the pumping system comprises a rotary induction motor, a motor casing, one or more pump stages, and a cooling system. The rotary induction motor rotates a shaft about a longitudinal axis of rotation. The motor casing houses the rotary induction motor such that the rotary induction motor is held in fluid isolation from the fluid being extracted. The pump stages are attached to the shaft outside of the motor casing, and are configured to impart fluid being extracted from the well with an increased pressure. The cooling system is disposed at least partially within the motor casing, and transfers heat generated by operation of the rotary induction motor out of the motor casing.

Parameters optimization of supercritical fluid-CO2 extracts of frankincense using response surface methodology and its pharmacodynamics effects.

PubMed

Zhou, Jing; Ma, Xing-miao; Qiu, Bi-Han; Chen, Jun-xia; Bian, Lin; Pan, Lin-mei

2013-01-01

The volatile oil parts of frankincense (Boswellia carterii Birdw.) were extracted with supercritical carbon dioxide under constant pressure (15, 20, or 25 MPa) and fixed temperature (40, 50, or 60°C), given time (60, 90, or 120 min) aiming at the acquisition of enriched fractions containing octyl acetate, compounds of pharmaceutical interest. A mathematical model was created by Box-Behnken design, a popular template for response surface methodology, for the extraction process. The response value was characterized by synthetical score, which comprised yields accounting for 20% and content of octyl acetate for 80%. The content of octyl acetate was determined by GC. The supercritical fluid extraction showed higher selectivity than conventional steam distillation. Supercritical fluid-CO(2) for extracting frankincense under optimum condition was of great validity, which was also successfully verified by the pharmacological experiments. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

9 CFR 319.721 - Fluid extract of meat.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Fluid extract of meat. 319.721 Section 319.721 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Beef”) shall contain not more than 50 percent of moisture. ...

9 CFR 319.721 - Fluid extract of meat.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Fluid extract of meat. 319.721 Section 319.721 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Beef”) shall contain not more than 50 percent of moisture. ...

9 CFR 319.721 - Fluid extract of meat.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Fluid extract of meat. 319.721 Section 319.721 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Beef”) shall contain not more than 50 percent of moisture. ...

9 CFR 319.721 - Fluid extract of meat.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Fluid extract of meat. 319.721 Section 319.721 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Beef”) shall contain not more than 50 percent of moisture. ...

9 CFR 319.721 - Fluid extract of meat.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Fluid extract of meat. 319.721 Section 319.721 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Beef”) shall contain not more than 50 percent of moisture. ...

Application of FTA technology to extraction of sperm DNA from mixed body fluids containing semen.

PubMed

Fujita, Yoshihiko; Kubo, Shin-ichi

2006-01-01

FTA technology is a novel method designed to simplify the collection, shipment, archiving and purification of nucleic acids from a wide variety of biological sources. In this study, we report a rapid and simple method of extracting DNA from sperm when body fluids mixed with semen were collected using FTA cards. After proteinase K digestion of the sperm and body fluid mixture, the washed pellet suspension as the sperm fraction and the concentrated supernatant as the epithelial cell fraction were respectively applied to FTA cards containing DTT. The FTA cards were dried, then directly added to a polymerase chain reaction (PCR) mix and processed by PCR. The time required from separation of the mixed fluid into sperm and epithelial origin DNA extractions was only about 2.5-3h. Furthermore, the procedure was extremely simple. It is considered that our designed DNA extraction procedure using an FTA card is available for application to routine work.

Actinide and lanthanide separation process (ALSEP)

DOEpatents

Guelis, Artem V.

2013-01-15

The process of the invention is the separation of minor actinides from lanthanides in a fluid mixture comprising, fission products, lanthanides, minor actinides, rare earth elements, nitric acid and water by addition of an organic chelating aid to the fluid; extracting the fluid with a solvent comprising a first extractant, a second extractant and an organic diluent to form an organic extractant stream and an aqueous raffinate. Scrubbing the organic stream with a dicarboxylic acid and a chelating agent to form a scrubber discharge. The scrubber discharge is stripped with a simple buffering agent and a second chelating agent in the pH range of 2.5 to 6.1 to produce actinide and lanthanide streams and spent organic diluents. The first extractant is selected from bis(2-ethylhexyl)hydrogen phosphate (HDEHP) and mono(2-ethylhexyl)2-ethylhexyl phosphonate (HEH(EHP)) and the second extractant is selected from N,N,N,N-tetra-2-ethylhexyl diglycol amide (TEHDGA) and N,N,N',N'-tetraoctyl-3-oxapentanediamide (TODGA).

Supercritical CO(2) fluid extraction of crystal water from trehalose dihydrate. Efficient production of form II (T(alpha)) phase.

PubMed

Akao, Ken-ichi; Okubo, Yusei; Inoue, Yoshio; Sakurai, Minoru

2002-10-11

Form II is a kind of metastable crystalline form of trehalose anhydrate, and it is easily converted to the dihydrate crystal by absorbing water in moist atmosphere at room temperature (Akao et al., Carbohydr. Res. 2001, 334, 233-241). It can be utilized as an edible and nontoxic desiccant, and thus its efficient production from the dihydrate is significant from a viewpoint of industrial applications. In this study, we attempt to extract crystal water from the dihydrate using supercritical CO(2). We examine the dependence of extraction efficiency on the extraction time, the temperature and pressure of the fluid. Then, FTIR measurements are carried out to detect the extracted water and to identify the polymorphic phase of the sugar sample after the extraction treatment. In particular, the so-called first derivative euclidean distance analysis for IR spectra is shown to be quite useful for the structural identification. Consequently, we demonstrate that form II is produced from the dihydrate through supercritical CO(2) fluid extraction if appropriate temperature and pressure conditions (around 80 degrees C and 20 MPa) are maintained.

Effect of saliva stabilisers on detection of porcine reproductive and respiratory syndrome virus in oral fluid by quantitative reverse transcriptase real-time PCR.

PubMed

Decorte, Inge; Van der Stede, Yves; Nauwynck, Hans; De Regge, Nick; Cay, Ann Brigitte

2013-08-01

This study evaluated the effect of extraction-amplification methods, storage temperature and saliva stabilisers on detection of porcine reproductive and respiratory syndrome virus (PRRSV) RNA by quantitative reverse transcriptase real-time PCR (qRT-PCR) in porcine oral fluid. The diagnostic performance of different extraction-amplification methods was examined using a dilution series of oral fluid spiked with PRRSV. To determine RNA stability, porcine oral fluid, with or without commercially available saliva stabilisers, was spiked with PRRSV, stored at 4°C or room temperature and tested for the presence of PRRSV RNA by qRT-PCR. PRRSV RNA could be detected in oral fluid using all extraction-amplification combinations, but the limit of detection varied amongst different combinations. Storage temperature and saliva stabilisers had an effect on the stability of PRRSV RNA, which could only be detected for 7 days when PRRSV spiked oral fluid was kept at 4°C or stabilised at room temperature with a commercial mRNA stabiliser. Copyright © 2013 Elsevier Ltd. All rights reserved.

Supercritical fluid extraction and processing of foods

USDA-ARS?s Scientific Manuscript database

Consumers are aware of the processing techniques used to manufacture food and health supplements and are concerned about the impact of those processes on their health and the environment. Processes that use supercritical fluids as an alternative to solvents that are used to extract nutrients and bio...

Environmentally safe fluid extractor

DOEpatents

Sungaila, Zenon F.

1993-01-01

An environmentally safe fluid extraction device for use in mobile laboratory and industrial settings comprising a pump, compressor, valving system, waste recovery tank, fluid tank, and a exhaust filtering system.

Environmentally safe fluid extractor

DOEpatents

Sungaila, Zenon F.

1993-07-06

An environmentally safe fluid extraction device for use in mobile laboratory and industrial settings comprising a pump, compressor, valving system, waste recovery tank, fluid tank, and a exhaust filtering system.

HERSCHEL OBSERVATIONS OF MAJOR MERGER PAIRS AT z = 0: DUST MASS AND STAR FORMATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cao, Chen; Xu, Cong Kevin; Lu, Nanyao

We present Herschel PACS and SPIRE far-infrared (FIR) and submillimeter imaging observations for a large K-band selected sample of 88 close major-merger pairs of galaxies (H-KPAIRs) in 6 photometric bands (70, 100, 160, 250, 350, and 500 μm). Among 132 spiral galaxies in the 44 spiral–spiral (S+S) pairs and 44 spiral–elliptical (S+E) pairs, 113 are detected in at least 1 Herschel band. The star formation rate (SFR) and dust mass (M{sub dust}) are derived from the IR SED fitting. The mass of total gas (M{sub gas}) is estimated by assuming a constant dust-to-gas mass ratio of 0.01. Star-forming spiral galaxiesmore » (SFGs) in S+S pairs show significant enhancements in both specific star formation rate (sSFR) and star formation efficiency (SFE), while having nearly the same gas mass compared to control galaxies. On the other hand, for SFGs in S+E pairs, there is no significant sSFR enhancement and the mean SFE enhancement is significantly lower than that of SFGs in S+S pairs. This suggests an important role for the disk–disk collision in the interaction-induced star formation. The M{sub gas} of SFGs in S+E pairs is marginally lower than that of their counterparts in both S+S pairs and the control sample. Paired galaxies with and without interaction signs do not differ significantly in their mean sSFR and SFE. As found in previous works, this much larger sample confirms that the primary and secondary spirals in S+S pairs follow a Holmberg effect correlation on sSFR.« less

TIDAL TAILS OF MINOR MERGERS. II. COMPARING STAR FORMATION IN THE TIDAL TAILS OF NGC 2782

DOE Office of Scientific and Technical Information (OSTI.GOV)

Knierman, Karen A.; Scowen, Paul; Veach, Todd

2013-09-10

The peculiar spiral NGC 2782 is the result of a minor merger with a mass ratio {approx}4: 1 occurring {approx}200 Myr ago. This merger produced a molecular and H I-rich, optically bright eastern tail and an H I-rich, optically faint western tail. Non-detection of CO in the western tail by Braine et al. suggested that star formation had not yet begun. However, deep UBVR and H{alpha} narrowband images show evidence of recent star formation in the western tail, though it lacks massive star clusters and cluster complexes. Using Herschel PACS spectroscopy, we discover 158 {mu}m [C II] emission at themore » location of the three most luminous H{alpha} sources in the eastern tail, but not at the location of the even brighter H{alpha} source in the western tail. The western tail is found to have a normal star formation efficiency (SFE), but the eastern tail has a low SFE. The lack of CO and [C II] emission suggests that the western tail H II region may have a low carbon abundance and be undergoing its first star formation. The western tail is more efficient at forming stars, but lacks massive clusters. We propose that the low SFE in the eastern tail may be due to its formation as a splash region where gas heating is important even though it has sufficient molecular and neutral gas to make massive star clusters. The western tail, which has lower gas surface density and does not form high-mass star clusters, is a tidally formed region where gravitational compression likely enhances star formation.« less

Supercritical-fluid extraction and chromatography-mass spectrometry for analysis of mycotoxins

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, R.D.; Udseth, H.R.

1982-07-01

The use of direct supercritical-fluid injection-mass spectrometry for the rapid analysis of mycotoxins of the tricothecene group is demonstrated. A solution containing diacetoxyscirpenol or T-2 toxin is injected into a fluid consisting primarily of pentane or carbon dioxide and is rapidly brought to supercritical conditions. Direct injection of the fluid stream into a chemical ionization source allows thermally labile compounds to be analyzed. Under these conditions trichothecene mass spectra showing significant (M + 1)/sup +/ ions and distinctive fragmentation patterns are obtained. Detection limits are in the subnanogram range. Direct analysis from complex substrates using selective supercritical-fluid extraction is proposed.more » 4 figures.« less

Cryo-optical testing of large aspheric reflectors operating in the sub mm range

NASA Astrophysics Data System (ADS)

Roose, S.; Houbrechts, Y.; Mazzoli, A.; Ninane, N.; Stockman, Y.; Daddato, R.; Kirschner, V.; Venacio, L.; de Chambure, D.

2006-02-01

The cryo-optical testing of the PLANCK primary reflector (elliptical off-axis CFRP reflector of 1550 mm x 1890 mm) is one of the major issue in the payload development program. It is requested to measure the changes of the Surface Figure Error (SFE) with respect to the best ellipsoid, between 293 K and 50 K, with a 1 μm RMS accuracy. To achieve this, Infra Red interferometry has been used and a dedicated thermo mechanical set-up has been constructed. This paper summarises the test activities, the test methods and results on the PLANCK Primary Reflector - Flight Model (PRFM) achieved in FOCAL 6.5 at Centre Spatial de Liege (CSL). Here, the Wave Front Error (WFE) will be considered, the SFE can be derived from the WFE measurement. After a brief introduction, the first part deals with the general test description. The thermo-elastic deformations will be addressed: the surface deformation in the medium frequency range (spatial wavelength down to 60 mm) and core-cell dimpling.

The synchronous improvement of strength and plasticity (SISP) in new Ni-Co based disc superalloys by controling stacking fault energy.

PubMed

Xu, H; Zhang, Z J; Zhang, P; Cui, C Y; Jin, T; Zhang, Z F

2017-08-14

It is a great challenge to improve the strength of disc superalloys without great loss of plasticity together since the microstructures benefiting the strength always do not avail the plasticity. Interestingly, this study shows that the trade-off relationship between strength and plasticity can be broken through decreasing stacking fault energy (SFE) in newly developed Ni-Co based disc superalloys. Axial tensile tests in the temperature range of 25 to 725 °C were carried out in these alloys with Co content ranging from 5% to 23% (wt.%). It is found that the ultimate tensile strength (UTS) and uniform elongation (UE) are improved synchronously when microtwinning is activated by decreasing the SFE at 650 and 725 °C. In contrast, only UTS is improved when stacking fault (SF) dominates the plastic deformation at 25 and 400 °C. These results may be helpful for designing advanced disc superalloys with relatively excellent strength and plasticity simultaneously.

Effect of interstitial and substitution alloying elements on the intrinsic stacking fault energy of nanocrystalline fcc-iron by atomistic simulation study

NASA Astrophysics Data System (ADS)

Mohammadzadeh, Mina; Mohammadzadeh, Roghayeh

2017-11-01

The stacking fault energy (SFE) is an important parameter in the deformation mechanism of face centered cubic (fcc) iron-based alloy. In this study, the effect of interstitial (C and N) and substitution (Nb and Ti) alloying elements on the intrinsic SFE (ISFE) of nanocrystalline iron were investigated via molecular dynamics (MD) simulation. The modified embedded atom method (MEAM) inter-atomic potential was used in the MD simulations. The results demonstrate a strong dependence of ISFE with addition of interstitial alloying elements but only a mild increase in ISFE with addition of substitution alloying elements in the composition range of 0 < {CNb, CTi} < 3 (at%). Moreover, it is shown that alloying of fcc iron with N decreases ISFE, whereas it increases significantly by addition of carbon element [0 < {CC, CN} < 3.5 (at%)]. The simulation method employed in this work shows reasonable agreement with some published experimental/calculated data.

Creep mechanisms of a new Ni-Co-base disc superalloy at an intermediate temperature.

PubMed

Yuan, Y; Gu, Y F; Zhong, Z H; Osada, T; Cui, C Y; Tetsui, T; Yokokawa, T; Harada, H

2012-10-01

The microstructures of a new Ni-Co-base disc superalloy, TMW-4M3, before and after the creep test at 725 °C/630 MPa have been systematically investigated by transmission electron microscopy (TEM). The crept microstructures were marked as three different deformation stages (I, II and III) corresponding to the gradually increased strain. At stage I, stacking fault (SF) shearing was the main deformation mechanism. The SF was extrinsic and lay on {111} plane. However, deformation microtwinning became the dominant mode at stage II and III. The average spacing of deformation twins decreased from 109 ± 15 nm at stage II to 76 ± 12 nm at stage III, whereas the twin thickness did not change significantly. The influence of stacking fault energy (SFE) of γ matrix on the deformation mechanism is discussed. It is suggested that lower SFE in TMW-4M3 is partly responsible for the enhanced creep resistance. © 2012 The Authors Journal of Microscopy © 2012 Royal Microscopical Society.

A thermo-mechanical correlation with driving forces for hcp martensite and twin formations in the Fe-Mn-C system exhibiting multicomposition sets.

PubMed

Nakano, Jinichiro

2013-02-01

The thermodynamic properties of the Fe-Mn-C system were investigated by using an analytical model constructed by a CALPHAD approach. The stacking fault energy (SFE) of the fcc structure with respect to the hcp phase was always constant at T 0 , independent of the composition and temperature when other related parameters were assumed to be constant. Experimental limits for the thermal hcp formation and the mechanical (deformation-induced) hcp formation were separated by the SFE at T 0 . The driving force for the fcc to hcp transition, defined as a dimensionless value -d G m /( RT ), was determined in the presence of Fe-rich and Mn-rich composition sets in each phase. Carbon tended to partition to the Mn-rich phase rather than to the Fe-rich phase for the compositions studied. The results obtained revealed a thermo-mechanical correlation with empirical yield strength, maximum true stress and maximum true strain. The proportionality between thermodynamics and mechanical properties is discussed.

Capturing the onset of the common cold and its effects on iron absorption.

PubMed

Hoppe, M; Hulthén, L

2007-08-01

Hypoferremia is a well-known response to infections and inflammatory disorders. It seems to be managed by the key mediator of iron kinetics, hepcidin. There are several studies on induced-acute phase reactions. However, to our best knowledge there are no previous published reports on the outbreak of a common cold and its initial effect on iron kinetics. The objective of this case report is to describe such an observation. From an apparently healthy state in the morning we observed, in a 28-year-old male, every hour for 6 h the outbreak of a common cold and the modulations in the levels of serum iron (S-Fe) and interleukin-6 (IL-6). Despite a 100 mg oral iron loading there was a substantial reduction in S-Fe, which seemed to precede the IL-6 peak. Interestingly, this observed succession is in conflict with the proposed infection chain of order in which IL-6 stimulates hepcidin induction.

Environmental dependence of star formation induced by cloud collisions in a barred galaxy

NASA Astrophysics Data System (ADS)

Fujimoto, Yusuke; Tasker, Elizabeth J.; Habe, Asao

2014-11-01

Cloud collision has been proposed as a way to link the small-scale star formation process with the observed global relation between the surface star formation rate and gas surface density. We suggest that this model can be improved further by allowing the productivity of such collisions to depend on the relative velocity of the two clouds. Our adjustment implements a simple step function that results in the most successful collisions being at the observed velocities for triggered star formation. By applying this to a high-resolution simulation of a barred galaxy, we successfully reproduce the observational result that the star formation efficiency (SFE) in the bar is lower than that in the spiral arms. This is not possible when we use an efficiency dependent on the internal turbulence properties of the clouds. Our results suggest that high-velocity collisions driven by the gravitational pull of the clouds are responsible for the low bar SFE.

Brochosomal coats turn leafhopper (Insecta, Hemiptera, Cicadellidae) integument to superhydrophobic state

PubMed Central

Rakitov, Roman; Gorb, Stanislav N.

2013-01-01

Leafhoppers (Insecta, Hemiptera, Cicadellidae) actively coat their integuments with brochosomes, hollow proteinaceous spheres of usually 200–700 nm in diameter, with honeycombed walls. The coats have been previously suggested to act as a water-repellent and anti-adhesive protective barrier against the insect's own exudates. We estimated their wettability through contact angle (CA) measurements of water, diiodomethane, ethylene glycol and ethanol on detached wings of the leafhoppers Alnetoidia alneti, Athysanus argentarius and Cicadella viridis. Intact brochosome-coated integuments were repellent to all test liquids, except ethanol, and exhibited superhydrophobicity, with the average water CAs of 165–172°, and the apparent surface free energy (SFE) estimates not exceeding 0.74 mN m−1. By contrast, the integuments from which brochosomes were removed with a peeling technique using fluid polyvinylsiloxane displayed water CAs of only 103–129° and SFEs above 20 mN m−1. Observations of water-sprayed wings in a cryo-scanning electron microscope confirmed that brochosomal coats prevented water from contacting the integument. Their superhydrophobic properties appear to result from fractal roughness, which dramatically reduces the area of contact with high-surface-tension liquids, including, presumably, leafhopper exudates. PMID:23235705

Optimization of conditions for supercritical fluid extraction of flavonoids from hops (Humulus lupulus L.)*

PubMed Central

He, Guo-qing; Xiong, Hao-ping; Chen, Qi-he; Ruan, Hui; Wang, Zhao-yue; Traoré, Lonseny

2005-01-01

Waste hops are good sources of flavonoids. Extraction of flavonoids from waste hops (SC-CO2 extracted hops) using supercritical fluids technology was investigated. Various temperatures, pressures and concentrations of ethanol (modifier) and the ratio (w/w) of solvent to material were tested in this study. The results of single factor and orthogonal experiments showed that at 50 °C, 25 MPa, the ratio of solvent to material (50%), ethanol concentration (80%) resulted in maximum extraction yield flavonoids (7.8 mg/g). HPLC-MS analysis of the extracts indicated that flavonoids obtained were xanthohumol, the principal prenylflavonoid in hops. PMID:16187413

An Analytical Model for Assessing Stability of Pre-Existing Faults in Caprock Caused by Fluid Injection and Extraction in a Reservoir

NASA Astrophysics Data System (ADS)

Wang, Lei; Bai, Bing; Li, Xiaochun; Liu, Mingze; Wu, Haiqing; Hu, Shaobin

2016-07-01

Induced seismicity and fault reactivation associated with fluid injection and depletion were reported in hydrocarbon, geothermal, and waste fluid injection fields worldwide. Here, we establish an analytical model to assess fault reactivation surrounding a reservoir during fluid injection and extraction that considers the stress concentrations at the fault tips and the effects of fault length. In this model, induced stress analysis in a full-space under the plane strain condition is implemented based on Eshelby's theory of inclusions in terms of a homogeneous, isotropic, and poroelastic medium. The stress intensity factor concept in linear elastic fracture mechanics is adopted as an instability criterion for pre-existing faults in surrounding rocks. To characterize the fault reactivation caused by fluid injection and extraction, we define a new index, the "fault reactivation factor" η, which can be interpreted as an index of fault stability in response to fluid pressure changes per unit within a reservoir resulting from injection or extraction. The critical fluid pressure change within a reservoir is also determined by the superposition principle using the in situ stress surrounding a fault. Our parameter sensitivity analyses show that the fault reactivation tendency is strongly sensitive to fault location, fault length, fault dip angle, and Poisson's ratio of the surrounding rock. Our case study demonstrates that the proposed model focuses on the mechanical behavior of the whole fault, unlike the conventional methodologies. The proposed method can be applied to engineering cases related to injection and depletion within a reservoir owing to its efficient computational codes implementation.

Fluid extraction using carbon dioxide and organophosphorus chelating agents

DOEpatents

Smart, N.G.; Wai, C.M.; Lin, Y.; Kwang, Y.H.

1998-11-24

Methods for extracting metalloid and metal species from a solid or liquid material by exposing the material to a fluid solvent, particularly supercritical CO{sub 2}, and a chelating agent are described. The chelating agent forms a chelate with the species, the chelate being soluble in the fluid to allow removal of the species from the material. In preferred embodiments the extraction solvent is supercritical CO{sub 2} and the chelating agent comprises an organophosphorous chelating agent, particularly sulfur-containing organophosphorous chelating agents, including mixtures of chelating agents. Examples of chelating agents include monothiophosphinic acid, di-thiophosphinic acid, phosphine sulfite, phosphorothioic acid, and mixtures thereof. The method provides an environmentally benign process for removing metal and metalloids from industrial waste solutions, particularly acidic solutions. Both the chelate and the supercritical fluid can be regenerated and the contaminant species recovered to provide an economic, efficient process. 1 fig.

Fluid extraction using carbon dioxide and organophosphorus chelating agents

DOEpatents

Smart, Neil G.; Wai, Chien M.; Lin, Yuehe; Kwang, Yak Hwa

1998-01-01

Methods for extracting metalloid and metal species from a solid or liquid material by exposing the material to a fluid solvent, particularly supercritical CO.sub.2, and a chelating agent are described. The chelating agent forms a chelate with the species, the chelate being soluble in the fluid to allow removal of the species from the material. In preferred embodiments the extraction solvent is supercritical CO.sub.2 and the chelating agent comprises an organophosphorous chelating agent, particularly sulfur-containing organophosphorous chelating agents, including mixtures of chelating agents. Examples of chelating agents include monothiophosphinic acid, di-thiophosphinic acid, phosphine sulfite, phosphorothioic acid, and mixtures thereof. The method provides an environmentally benign process for removing metal and metalloids from industrial waste solutions, particularly acidic solutions. Both the chelate and the supercritical fluid can be regenerated and the contaminant species recovered to provide an economic, efficient process.

In-situ remediation system and method for contaminated groundwater

DOEpatents

Corey, John C.; Looney, Brian B.; Kaback, Dawn S.

1989-01-01

A system for removing volatile contaminants from a subsurface plume of contamination comprising two sets of wells, a well for injecting a fluid into a saturated zone on one side of the plume and an extracting well for collecting the fluid together with volatilized contaminants from the plume on the other side of the plume. The fluid enables the volatile contaminants to be volatilized and carried therewith through the ground to the extracting well. Injecting and extracting wells are preferably horizontal wells positioned below the plume in the saturated zone and above the plume in the vadose zone, respectively. The fluid may be air or other gas or a gas and liquid mixture depending on the type of contaminant to be removed and may be preheated to facilitate volatilization. Treatment of the volatilized contamination may be by filtration, incineration, atmospheric dispersion or the like.

In-situ remediation system and method for contaminated groundwater

DOEpatents

Corey, J.C.; Looney, B.B.; Kaback, D.S.

1989-05-23

A system for removing volatile contaminants from a subsurface plume of contamination comprising two sets of wells, a well for injecting a fluid into a saturated zone on one side of the plume and an extracting well for collecting the fluid together with volatilized contaminants from the plume on the other side of the plume. The fluid enables the volatile contaminants to be volatilized and carried therewith through the ground to the extracting well. Injecting and extracting wells are preferably horizontal wells positioned below the plume in the saturated zone and above the plume in the vadose zone, respectively. The fluid may be air or other gas or a gas and liquid mixture depending on the type of contaminant to be removed and may be preheated to facilitate volatilization. Treatment of the volatilized contamination may be by filtration, incineration, atmospheric dispersion or the like. 3 figs.

Comparison of two different solvents employed for pressurised fluid extraction of stevioside from Stevia rebaudiana: methanol versus water.

PubMed

Pól, Jaroslav; Varadová Ostrá, Elena; Karásek, Pavel; Roth, Michal; Benesová, Karolínka; Kotlaríková, Pavla; Cáslavský, Josef

2007-08-01

Pressurised fluid extraction using water or methanol was employed for the extraction of stevioside from Stevia rebaudiana Bertoni. The extraction method was optimised in terms of temperature and duration of the static or the dynamic step. Extracts were analysed by liquid chromatography followed by UV and mass-spectrometric (MS) detections. Thermal degradation of stevioside was the same in both solvents within the range 70-160 degrees C. Methanol showed better extraction ability for isolation of stevioside from Stevia rebaudiana leaves than water within the range 110-160 degrees C. However, water represents the green alternative to methanol. The limit of detection of stevioside in the extract analysed was 30 ng for UV detection and 2 ng for MS detection.

Determination of fluid extraction and osmotic conductance sigma K in the lung with hypertonic NaCl infusion. I. Theory.

PubMed

Hunter, M; Lee, J

1992-11-01

A dispersion and extraction model of the lung is developed to assess how the infusion of hypertonic saline into the pulmonary artery changes the gravimetric density of pulmonary venous blood. The dispersion analysis is built on the indicator dilution curve measured for the pulmonary circulation. The extraction model consists of microvascular and interstitial compartments separated by a permeable pulmonary endothelium. Because the density of fluid extracted by the hypertonic disturbance is lower than the blood density, the extraction leads to a decrease in blood density. Two cases of fluid extraction are analyzed, a hypertonic infusion to elevate the osmotic pressure in the pulmonary arterial blood in the form of a step function and an infusion performed over a period of 1 sec. Both cases show that the dispersion significantly attenuates the changes in osmotic pressure and density as they are transported by the blood along the pulmonary vasculature. Because the model has taken into account the effect of dispersion and pulmonary blood flow, the equations developed here provide the basis to calculate from the density change in pulmonary venous blood the characteristics of osmotic extraction intrinsic to the lung.

Numerical simulation of stress distribution in Inconel 718 components realized by metal injection molding during supercritical debinding

NASA Astrophysics Data System (ADS)

Agne, Aboubakry; Barrière, Thierry

2018-05-01

Metal injection molding (MIM) is a process combining advantages of thermoplastic injection molding and powder metallurgy process in order to manufacture components with complex and near net-shape geometries. The debinding of a green component can be performed in two steps, first by using solvent debinding in order to extract the organic part of the binder and then by thermal degradation of the rest of the binder. A shorter and innovative method for extracting an organic binder involves the use of supercritical fluid instead of a regular solvent. The debinding via a supercritical fluid was recently investigated to extract organic binders contained in components obtained by Metal Injection Molding. It consists to put the component in an enclosure subjected to high pressure and temperature. The supercritical fluid has various properties depending on these two conditions, e.g., density and viscosity. The high-pressure combined with the high temperature during the process affect the component structure. Three mechanisms contributing to the deformation of the component can been differentiated: thermal expansion, binder extraction and supercritical fluid effect on the outer surfaces of the component. If one supposes that, the deformation due to binder extraction is negligible, thermal expansion and the fluid effect are probably the main mechanisms that can produce several stress. A finite-element model, which couples fluid-structures interaction and structural mechanics, has been developed and performed on the Comsol Multiphysics® finite-element software platform allowed to estimate the stress distribution during the supercritical debinding of MIM component composed of Inconel 718 powders, polypropylene, polyethylene glycol and stearic acid as binder. The proposed numerical simulations allow the estimation of the stress distribution with respect to the processing parameters for MIM components during the supercritical debinding process using a stationary solver.

In vitro digestive fluid extraction as a measure of the bioavailability of sediment-associated polycyclic aromatic hydrocarbons: Sources of variation and implications for partitioning models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weston, D.P.; Mayer, L.M.

1998-05-01

In vitro extraction of contaminated sediments using the digestive fluid of a deposit-feeding polychaete has recently been proposed to study contaminant bioaccumulation mechanisms and perhaps to better quantify the bioavailable contaminant fraction. This approach was evaluated using digestive fluid from the polychaete Arenicola brasiliensis and six marine sediments containing both spiked radiolabeled polycyclic aromatic hydrocarbons (PAHs) and in situ-contaminated unlabeled PAHs. The proportion of total contaminant extracted by digestive fluid from each sediment varied from 22 to 71% and 13 to 52%, for phenanthrene and benzo[a]pyrene, respectively. The proportions of contaminant solubilized were inversely correlated with the sediments` organic carbonmore » content. The extent of PAH solubilization among sediments by A. brasiliensis digestive fluid was highly correlated with that of digestive fluid from the echiuran Urechis caupo and appears to be a consequence of surfactant properties of the fluids rather than of their enzymatic activity. The proportion of PAHs solubilized in vitro was similar to in vivo measurements of solubilization for contaminant exposures lasting about 24 h. However, with continued exposure, in vivo PAH concentrations in the digestive fluid increased fivefold, suggesting that digestive fluid is retained in the gut longer than sediment and thus accumulates PAHs through sequential digestion of many gut volumes. This phenomenon may enhance contaminant fugacity in the gut and increase the potential for bioaccumulation or toxicity.« less

Supercritical fluid processing: opportunities for new resist materials and processes

NASA Astrophysics Data System (ADS)

Gallagher-Wetmore, Paula M.; Ober, Christopher K.; Gabor, Allen H.; Allen, Robert D.

1996-05-01

Over the past two decades supercritical fluids have been utilized as solvents for carrying out separations of materials as diverse as foods, polymers, pharmaceuticals, petrochemicals, natural products, and explosives. More recently they have been used for non-extractive applications such as recrystallization, deposition, impregnation, surface modification, and as a solvent alternative for precision parts cleaning. Today, supercritical fluid extraction is being practiced in the foods and beverage industries; there are commercial plants for decaffeinating coffee and tea, extracting beer flavoring agents from hops, and separating oils and oleoresins from spices. Interest in supercritical fluid processing of polymers has grown over the last ten years, and many new purification, fractionation, and even polymerization techniques have emerged. One of the most significant motivations for applying this technology to polymers has been increased performance demands. More recently, with increasing scrutiny of traditional solvents, supercritical fluids, and in particular carbon dioxide, are receiving widespread attention as 'environmentally conscious' solvents. This paper describes several examples of polymers applications, including a few involving photoresists, which demonstrate that as next- generation advanced polymer systems emerge, supercritical fluids are certain to offer advantages as cutting edge processing tools.

Method and apparatus for back-extracting metal chelates

DOEpatents

Wai, Chien M.; Smart, Neil G.; Lin, Yuehe

1998-01-01

A method of extracting metal and metalloid species from a solid or liquid substrate using a supercritical fluid solvent containing one or more chelating agents followed by back-extracting the metal and metalloid species from the metal and metalloid chelates formed thereby. The back-extraction acidic solution is performed utilizing an acidic solution. Upon sufficient exposure of the metal and metalloid chelates to the acidic solution, the metal and metalloid species are released from the chelates into the acid solution, while the chelating agent remains in the supercritical fluid solvent. The chelating agent is thereby regenerated and the metal and metalloid species recovered.

Supercritical carbon dioxide extraction of 2,4-dichlorophenol from food crop tissues.

PubMed

Thomson, C A; Chesney, D J

1992-04-15

Supercritical fluid extraction with carbon dioxide has been found to be effective for the isolation of residue levels (0.1-1 ppm) of 2,4-dichlorophenol from selected plant tissues. The 2,4-dichlorophenol residues were incompletely extracted with supercritical CO2 alone, since a substantial fraction of the 2,4-dichlorophenol was covalently attached to the plant matrix. An acid pretreatment procedure was developed to partially hydrolyze the plant tissue prior to extraction, releasing the bound 2,4-dichlorophenol residues. Steam distillation showed higher residue levels for field-treated straw samples. This is attributed to the greater degree of hydrolysis inherent in the steam distillation procedure. Supercritical CO2 extraction of field-treated seed samples showed higher levels of 2,4-dichlorophenol residues than did steam distillation. The supercritical fluid extractant was able to solvate 2,4-dichlorophenol residues in the interior of the seed and transport them to the surface for collection. The aqueous medium used in steam distillation was unable to penetrate the hydrophobic seed matrix to the same degree. While the actual extraction time experienced in supercritical fluid extraction was far less than that of steam distillation (45 min vs 6 h, respectively), the total sample preparation time was similar in both methods.

Analysis of Supercritical-Extracted Chelated Metal Ions From Mixed Organic-Inorganic Samples

NASA Technical Reports Server (NTRS)

Sinha, Mahadeva P. (Inventor)

1996-01-01

Organic and inorganic contaminants of an environmental sample are analyzed by the same GC-MS instrument by adding an oxidizing agent to the sample to oxidize metal or metal compounds to form metal ions. The metal ions are converted to chelate complexes and the chelate complexes are extracted into a supercritical fluid such as CO2. The metal chelate extract after flowing through a restrictor tube is directly injected into the ionization chamber of a mass spectrometer, preferably containing a refractory metal filament such as rhenium to fragment the complex to release metal ions which are detected. This provides a fast, economical method for the analysis of metal contaminants in a sample and can be automated. An organic extract of the sample in conventional or supercritical fluid solvents can be detected in the same mass spectrometer, preferably after separation in a supercritical fluid chromatograph.

Electrolysis Performance Improvement and Validation Experiment

NASA Technical Reports Server (NTRS)

Schubert, Franz H.

1992-01-01

Viewgraphs on electrolysis performance improvement and validation experiment are presented. Topics covered include: water electrolysis: an ever increasing need/role for space missions; static feed electrolysis (SFE) technology: a concept developed for space applications; experiment objectives: why test in microgravity environment; and experiment description: approach, hardware description, test sequence and schedule.

Storytelling for Empowerment for Latino Teens: Increasing HIV Prevention Knowledge and Attitudes

ERIC Educational Resources Information Center

Nelson, Annabelle; Cordova, David; Walters, Andrew S.; Szecsy, Elsie

2016-01-01

Latino adolescents are disproportionately impacted by HIV, but researchers have documented few programs to prevent and reduce HIV risk. The Storytelling for Empowerment (SFE) "HIV StoryBook" was designed with an innovative ecodevelopment approach combining empowerment, family communication, and positive cultural identity. A mixed method…

Diethylstilbestrol in fish tissue determined through subcritical fluid extraction and with GC-MS

NASA Astrophysics Data System (ADS)

Qiao, Qinghui; Shi, Nianrong; Feng, Xiaomei; Lu, Jie; Han, Yuqian; Xue, Changhu

2016-06-01

As the key point in sex hormone analysis, sample pre-treatment technology has attracted scientists' attention all over the world, and the development trend of sample preparation forwarded to faster and more efficient technologies. Taking economic and environmental concerns into account, subcritical fluid extraction as a faster and more efficient method has stood out as a sample pre-treatment technology. This new extraction technology can overcome the shortcomings of supercritical fluid and achieve higher extraction efficiency at relatively low pressures and temperatures. In this experiment, a simple, sensitive and efficient method has been developed for the determination of diethylstilbestrol (DES) in fish tissue using subcritical 1,1,1,2-tetrafluoroethane (R134a) extraction in combination with gas chromatography-mass spectrometry (GC-MS). After extraction, freezing-lipid filtration was utilized to remove fatty co-extract. Further purification steps were performed with C18 and NH2 solid phase extraction (SPE). Finally, the analyte was derived by heptafluorobutyric anhydride (HFBA), followed by GC-MS analysis. Response surface methodology (RSM) was employed to optimizing the extraction condition, and the optimized was as follows: extraction pressure, 4.3 MPa; extraction temperature, 26°C; amount of co-solvent volume, 4.7 mL. Under this condition, at a spiked level of 1, 5, 10 μg kg-1, the mean recovery of DES was more than 90% with relative standard deviations (RSDs) less than 10%. Finally, the developed method has been successfully used to analyzing the real samples.

A New Method of Obtaining High-Resolution Paleoclimate Records from Speleothem Fluid Inclusions

NASA Astrophysics Data System (ADS)

Logan, A. J.; Horton, T. W.

2010-12-01

We present a new method for stable hydrogen and oxygen isotope analysis of ancient drip water trapped within cave speleothems. Our method improves on existing fluid inclusion isotopic analytical techniques in that it decreases the sample size by a factor of ten or more, dramatically improving the spatial and temporal precision of fluid inclusion-based paleoclimatology. Published thermal extraction methods require large samples (c. 150 mg) and temperatures high enough (c. 500-900°C) to cause calcite decomposition, which is also associated with isotopic fractionation of the trapped fluids. Extraction by crushing faces similar challenges, where the failure to extract all the trapped fluid can result in isotopic fractionation, and samples in excess of 500 mg are required. Our new method combines the strengths of these published thermal and crushing methods using continuous-flow isotope ratio analytical techniques. Our method combines relatively low-temperature (~250°C) thermal decrepitation with cryogenic trapping across a switching valve sample loop. In brief, ~20 mg carbonate samples are dried (75°C for >1 hour) and heated (250°C for >1 hour) in a quartz sample chamber under a continuously flowing stream of ultra-high purity helium. Heating of the sample chamber is achieved by use of a tube furnace. Fluids released during the heating step are trapped in a coiled stainless steel cold trap (~ -98°C) serving as the sample loop in a 6-way switching valve. Trapped fluids are subsequently injected into a high-temperature conversion elemental analyzer by switching the valve and rapidly thawing the trap. This approach yielded accurate and precise measurements of injected liquid water IAEA reference materials (GISP; SMOW2; SLAP2) for both hydrogen and oxygen isotopic compositions. Blanking tests performed on the extraction line demonstrate extremely low line-blank peak heights (<50mv). Our tests also demonstrate that complete recovery of liquid water is possible and that a minimum quantity of ~100nL water was required. In contrast to liquid water analyses, carbonate inclusion waters gave highly variable results. As plenty of signal was produced from relatively small sample sizes (~20 mg), the observed isotopic variation most likely reflects fractionation during fluid extraction, or natural isotopic variability. Additional tests and modifications to the extraction procedure are in progress, using a recently collected New Zealand stalagmite from a West Coast cave (DOC collection permit WC-27462-GEO). U-Th age data will accompany a paleoclimate record from this stalagmite obtained using standard carbonate analytical techniques, and compared to the results from our new fluid inclusion analyses.

Antimicrobial activity and composition profile of grape (Vitis vinifera) pomace extracts obtained by supercritical fluids.

PubMed

Oliveira, Daniela A; Salvador, Ana Augusta; Smânia, Artur; Smânia, Elza F A; Maraschin, Marcelo; Ferreira, Sandra R S

2013-04-10

The possibility of increasing the aggregated value of the huge amount of residues generated by wineries around the world foment studies using the grape pomace - the residue from the wine production, composed by seed, skin and stems - to obtain functional ingredients. Nowadays, consumers in general prefer natural and safe products mainly for food and cosmetic fields, where the supercritical fluid extraction is of great importance due to the purity of the extracts provided. Therefore, the objective of this work is to evaluate the global extraction yield, the antimicrobial activity and the composition profile of Merlot and Syrah grape pomace extracts obtained by supercritical CO2 (SC-CO2) and CO2 added with co-solvent at pressures up to 300 bar and temperatures of 50 and 60 °C. The results were compared with the ones obtained by Soxhlet and by ultrasound-assisted leaching extraction methods. The main components from the extracts, identified by HPLC, were gallic acid, p-OH-benzoic acid, vanillic acid and epicatechin. The antibacterial and antifungal activities of the extracts were evaluated using four strains of bacteria (Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa) and three fungi strains (Candida albicans, Candida parapsilosis, Candida krusei). Despite lower extraction yield results, the supercritical fluid extracts presented the highest antimicrobial effectiveness compared to the other grape pomace extracts due to the presence of antimicrobial active compounds. Syrah extracts were less efficient against the microorganisms tested and Merlot extracts were more active against Gram-positive bacteria. Copyright © 2012 Elsevier B.V. All rights reserved.

Modeling of the Kinetics of Supercritical Fluid Extraction of Lipids from Microalgae with Emphasis on Extract Desorption

PubMed Central

Sovová, Helena; Nobre, Beatriz P.; Palavra, António

2016-01-01

Microalgae contain valuable biologically active lipophilic substances such as omega-3 fatty acids and carotenoids. In contrast to the recovery of vegetable oils from seeds, where the extraction with supercritical CO2 is used as a mild and selective method, economically viable application of this method on similarly soluble oils from microalgae requires, in most cases, much higher pressure. This paper presents and verifies hypothesis that this difference is caused by high adsorption capacity of microalgae. Under the pressures usually applied in supercritical fluid extraction from plants, microalgae bind a large fraction of the extracted oil, while under extremely high CO2 pressures their adsorption capacity diminishes and the extraction rate depends on oil solubility in supercritical CO2. A mathematical model for the extraction from microalgae was derived and applied to literature data on the extraction kinetics in order to determine model parameters. PMID:28773546

Antioxidant activity and sensory evaluation of a rosmarinic acid-enriched extract of Salvia officinalis

USDA-ARS?s Scientific Manuscript database

An extract of S. officinalis (garden sage) was developed using supercritical fluid extraction, followed by hot water extraction. The resulting extract was enriched in polyphenols, including rosmarinic acid (RA), which has shown promising health benefits in animals. The extract contained RA at a conc...

Method and turbine for extracting kinetic energy from a stream of two-phase fluid

NASA Technical Reports Server (NTRS)

Elliott, D. G. (Inventor)

1979-01-01

An axial flow separator turbine is described which includes a number of nozzles for delivering streams of a two-phase fluid along linear paths. A phase separator which responsively separates the vapor and liquid is characterized by concentrically related annuli supported for rotation within the paths. The separator has endless channels for confining the liquid under the influence of centrifugal forces. A vapor turbine fan extracts kinetic energy from the liquid. Angular momentum of both the liquid phase and the vapor phase of the fluid is converted to torque.

Supercritical fluid extraction and analysis of compounds from Clivia miniata for uterotonic activity.

PubMed

Sewram, V; Raynor, M W; Mulholland, D A; Raidoo, D M

2001-07-01

In this descriptive study, the superciritical fluid extract of the roots of Clivia miniata L. was tested for uterotonic activity using guinea pig uterine smooth muscle in vitro. Extraction was performed with water modified supercritical carbon dioxide at 400 atm and 80 degrees C. The uterine contractions induced by this extract were compared to those induced by the aqueous extract and found to be active at lower doses. The active compounds were isolated and the structures elucidated by spectroscopic and chromatographic techniques. Both linoleic acid and 5-hydroxymethyl-2-furancarboxaldehyde isolated from the extract were found to induce muscle contractions individually. The pharmacological mode of action of 5-hydroxymethyl-2-furancarboxaldehyde was assessed using two receptor agonists and antagonists. This compound was found to mediate its effect through cholinergic receptors.

Methodology for extracting local constants from petroleum cracking flows

DOEpatents

Chang, Shen-Lin; Lottes, Steven A.; Zhou, Chenn Q.

2000-01-01

A methodology provides for the extraction of local chemical kinetic model constants for use in a reacting flow computational fluid dynamics (CFD) computer code with chemical kinetic computations to optimize the operating conditions or design of the system, including retrofit design improvements to existing systems. The coupled CFD and kinetic computer code are used in combination with data obtained from a matrix of experimental tests to extract the kinetic constants. Local fluid dynamic effects are implicitly included in the extracted local kinetic constants for each particular application system to which the methodology is applied. The extracted local kinetic model constants work well over a fairly broad range of operating conditions for specific and complex reaction sets in specific and complex reactor systems. While disclosed in terms of use in a Fluid Catalytic Cracking (FCC) riser, the inventive methodology has application in virtually any reaction set to extract constants for any particular application and reaction set formulation. The methodology includes the step of: (1) selecting the test data sets for various conditions; (2) establishing the general trend of the parametric effect on the measured product yields; (3) calculating product yields for the selected test conditions using coupled computational fluid dynamics and chemical kinetics; (4) adjusting the local kinetic constants to match calculated product yields with experimental data; and (5) validating the determined set of local kinetic constants by comparing the calculated results with experimental data from additional test runs at different operating conditions.

High throughput screening and antioxidant assay of dibenzo[a,c]cyclooctadiene lignans in modified-ultrasonic and supercritical fluid extracts of Schisandra chinensis Baill by liquid chromatography--mass spectrometry and a free radical-scavenging method.

PubMed

Wang, Ming-Chih; Lai, Yih-Cherng; Chang, Chia-Lin

2008-05-01

Dibenzo[a,c]cyclooctadiene lignans of Schisandra chinensis Baill are well known because of their hepatoprotective activity, antioxidant activity, and anticancer effect. For the isolation of the dibenzo[a,c]cyclooctadiene lignans of Schisandra chinensis Baill two extraction methods were used: modified-ultrasonic extraction and supercritical fluid extraction. A specific and fast analytical method for structure identification is established for quality control because structure elucidation could be accomplished by means of liquid chromatography-mass spectrometry (LC-MS) technologies. The separation and identification of the compounds were completed by: (i) a water-acetonitrile gradient system using a C18 reversed-phase column; (ii) UV detection at 225 nm; (iii) MS/MS experiments with electrospray ionization interface (ESI) ion trap mass spectrometry in the positive mode. Normalized collision energy was used to obtain fragment ions of structural relevance in the LC-MS/MS. These results provided a reliable LC-MS/MS method for the determination of the dibenzo[a,c]cyclooctadiene lignans from Schisandra chinensis Baill. Finally, we also detected 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging effects (%) of the modified-ultrasonic and supercritical fluid extracts of Schisandra chinensis Baill compared with 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox). The antioxidant activities of the modified-ultrasonic and supercritical fluid extracts were lower than that of trolox.

Helium measurements of pore fluids obtained from the San Andreas Fault Observatory at Depth (SAFOD, USA) drill cores

NASA Astrophysics Data System (ADS)

Ali, S.; Stute, M.; Torgersen, T.; Winckler, G.; Kennedy, B. M.

2011-02-01

4He accumulated in fluids is a well established geochemical tracer used to study crustal fluid dynamics. Direct fluid samples are not always collectable; therefore, a method to extract rare gases from matrix fluids of whole rocks by diffusion has been adapted. Helium was measured on matrix fluids extracted from sandstones and mudstones recovered during the San Andreas Fault Observatory at Depth (SAFOD) drilling in California, USA. Samples were typically collected as subcores or from drillcore fragments. Helium concentration and isotope ratios were measured 4-6 times on each sample, and indicate a bulk 4He diffusion coefficient of 3.5 ± 1.3 × 10-8 cm2 s-1 at 21°C, compared to previously published diffusion coefficients of 1.2 × 10-18 cm2 s-1 (21°C) to 3.0 × 10-15 cm2 s-1 (150°C) in the sands and clays. Correcting the diffusion coefficient of 4Hewater for matrix porosity (˜3%) and tortuosity (˜6-13) produces effective diffusion coefficients of 1 × 10-8 cm2 s-1 (21°C) and 1 × 10-7 (120°C), effectively isolating pore fluid 4He from the 4He contained in the rock matrix. Model calculations indicate that <6% of helium initially dissolved in pore fluids was lost during the sampling process. Complete and quantitative extraction of the pore fluids provide minimum in situ porosity values for sandstones 2.8 ± 0.4% (SD, n = 4) and mudstones 3.1 ± 0.8% (SD, n = 4).

Activity and immunodetection of lysozyme in earthworm Dendrobaena veneta (Annelida).

PubMed

Fiołka, Marta J; Zagaja, Mirosław P; Hułas-Stasiak, Monika; Wielbo, Jerzy

2012-01-01

In the present study, lysozyme-like activity against Micrococcus luteus was detected in the coelomic fluid, the extract from coelomocytes, intestine and in the homogenates from cocoons of Dendrobaena veneta. Four hours after immunization with Escherichia coli, the lysozyme activity in the coelomic fluid increased about three times and in the extract of coelomocytes - four times, in comparison to the control. In three cases: of the coelomic fluid, the homogenates from cocoons and the extract from coelomocytes, the antibody against HEWL (hen egg white lysozyme) recognized only one protein with a molecular mass of about 14.4 kDa. In the coelomic fluid, apart from the protein with molecular mass of 14.4 kDa the antibody directed against human lysozyme recognized an additional protein of 22 kDa. Using the bioautography technique after electrophoretic resolution of native proteins in acidic polyacrylamide gels, two lytic zones of M. luteus were observed in the case of the coelomic fluid and three after the analysis of the extract of coelomocytes and the egg homogenates. The results indicated the existence of several forms of lysozyme with a different electric charge in the analyzed D. veneta samples. The highest lysozyme activity in the intestine of D. veneta was observed in the midgut. The antibody directed against human lysozyme indicated a strong positive signal in epidermal and midgut cells of earthworm. Copyright © 2011 Elsevier Inc. All rights reserved.

Determination of in vitro isoflavone degradation in rumen fluid.

PubMed

Trnková, Andrea; Šancová, Kateřina; Zapletalová, Martina; Kašparovská, Jitka; Dadáková, Kateřina; Křížová, Ludmila; Lochman, Jan; Hadrová, Sylvie; Ihnatová, Ivana; Kašparovský, Tomáš

2018-06-01

The aim of this study was to determine the degradation of dietary isoflavones in rumen fluid under 2 feeding regimens. The experiments were performed in vitro using a rumen fluid buffer system. The rumen fluid was taken from cows fed either a hay diet or a concentrate-rich diet (the diet consisted of 34.6% maize silage, 17.6% haylage, 12.8% alfalfa hay, and 35.0% supplemental mixture on a dry matter basis). As a source of isoflavones, 40% soybean extract (Biomedica, Prague, Czech Republic) at levels of 5, 25, 50, and 75 mg per 40 mL of rumen fluid was used. Samples of soybean extract were incubated in triplicate at 39°C for 0, 3.0, 6.0, 12.0, and 24.0 h in incubation solution. The metabolism of daidzein and genistein was faster under concentrate-rich diet conditions. In general, production of equol started after 3 to 6 h of incubation and reached the highest rate after approximately 12 h of incubation regardless of the type of diet or concentration of extract. In most of the experiments, production of equol continued after 24 h of incubation. Generally, equol production was greater under the hay diet conditions. Furthermore, experiments with higher amounts of added soybean extract revealed possible inhibitory effects of high levels of isoflavones on the rumen microflora. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Method and apparatus for back-extracting metal chelates

DOEpatents

Wai, C.M.; Smart, N.G.; Lin, Y.

1998-08-11

A method is described for extracting metal and metalloid species from a solid or liquid substrate using a supercritical fluid solvent containing one or more chelating agents followed by back-extracting the metal and metalloid species from the metal and metalloid chelates formed thereby. The back-extraction acidic solution is performed utilizing an acidic solution. Upon sufficient exposure of the metal and metalloid chelates to the acidic solution, the metal and metalloid species are released from the chelates into the acid solution, while the chelating agent remains in the supercritical fluid solvent. The chelating agent is thereby regenerated and the metal and metalloid species recovered. 3 figs.

Bi-directionally draining pore fluid extraction vessel

DOEpatents

Prizio, Joseph; Ritt, Alexander; Mower, Timothy E.; Rodine, Lonn

1991-01-01

The invention is used to extract pore fluid from porous solids through a combination of mechanical compression and inert-gas injection and comprises a piston for axially compressing samples to force water out, and top and bottom drainage plates for capturing the exuded water and using inert gas to force water to exit when the limits of mechanical compression have been reached.

Integration of phase separation with ultrasound-assisted salt-induced liquid-liquid microextraction for analyzing the fluoroquinones in human body fluids by liquid chromatography.

PubMed

Wang, Huili; Gao, Ming; Wang, Mei; Zhang, Rongbo; Wang, Wenwei; Dahlgren, Randy A; Wang, Xuedong

2015-03-15

Herein, we developed a novel integrated device to perform phase separation based on ultrasound-assisted salt-induced liquid-liquid microextraction for determination of five fluoroquinones (FQs) in human body fluids. The integrated device consisted of three simple HDPE components used to separate the extraction solvent from the aqueous phase prior to retrieving the extractant. A series of extraction parameters were optimized using the response surface method based on central composite design. Optimal conditions consisted of 945μL acetone extraction solvent, pH 2.1, 4.1min stir time, 5.9g Na2SO4, and 4.0min centrifugation. Under optimized conditions, the limits of detection (at S/N=3) were 0.12-0.66μgL(-1), the linear range was 0.5-500μgL(-1) and recoveries were 92.6-110.9% for the five FQs extracted from plasma and urine. The proposed method has several advantages, such as easy construction from inexpensive materials, high extraction efficiency, short extraction time, and compatibility with HPLC analysis. Thus, this method shows excellent prospects for sample pretreatment and analysis of FQs in human body fluids. Copyright © 2015 Elsevier B.V. All rights reserved.

Mathematical model of simple spalling formation during coal cutting with extracting machine

NASA Astrophysics Data System (ADS)

Gabov, V. V.; Zadkov, D. A.

2018-05-01

A single-mass model of a rotor shearer is analyzed. It is shown that rotor mining machines has large inertia moments and load dynamics. An extraction module model with selective movement of the cutting tool is represented. The peculiar feature of such extracting machines is fluid power drive cutter mechanism. They can steadily operate at large shear thickness, and locking modes are not an emergency for them. Comparing with shearers they have less inertional mass, but slower average cutting speed, and its momentary values depend on load. Basing on the equation of hydraulic fuel consumption balance the work of fluid power drive of extracting module cutter mechanism together with hydro pneumatic accumulator is analyzed. Spalling formation model during coal cutting with fluid power drive cutter mechanism and potential energy stores are suggested. Matching cutter speed with the speed of main crack expansion and amount of potential energy consumption, cutter load is determined only by ultimate stress at crack pole and friction. Tests of an extracting module cutter in real size model proved the stated theory.

Fluid extraction across pumping and permeable walls in the viscous limit

NASA Astrophysics Data System (ADS)

Herschlag, G.; Liu, J.-G.; Layton, A. T.

2016-04-01

In biological transport mechanisms such as insect respiration and renal filtration, fluid travels along a leaky channel allowing material exchange with systems exterior to the channel. The channels in these systems may undergo peristaltic pumping which is thought to enhance the material exchange. To date, little analytic work has been done to study the effect of pumping on material extraction across the channel walls. In this paper, we examine a fluid extraction model in which fluid flowing through a leaky channel is exchanged with fluid in a reservoir. The channel walls are allowed to contract and expand uniformly, simulating a pumping mechanism. In order to efficiently determine solutions of the model, we derive a formal power series solution for the Stokes equations in a finite channel with uniformly contracting/expanding permeable walls. This flow has been well studied in the case in which the normal velocity at the channel walls is proportional to the wall velocity. In contrast we do not assume flow that is proportional to the wall velocity, but flow that is driven by hydrostatic pressure, and we use Darcy's law to close our system for normal wall velocity. We incorporate our flow solution into a model that tracks the material pressure exterior to the channel. We use this model to examine flux across the channel-reservoir barrier and demonstrate that pumping can either enhance or impede fluid extraction across channel walls. We find that associated with each set of physical flow and pumping parameters, there are optimal reservoir conditions that maximize the amount of material flowing from the channel into the reservoir.

Design of a water electrolysis flight experiment

NASA Technical Reports Server (NTRS)

Lee, M. Gene; Grigger, David J.; Thompson, C. Dean; Cusick, Robert J.

1993-01-01

Supply of oxygen (O2) and hydrogen (H2) by electolyzing water in space will play an important role in meeting the National Aeronautics and Space Administration's (NASA's) needs and goals for future space missios. Both O2 and H2 are envisioned to be used in a variety of processes including crew life support, spacecraft propulsion, extravehicular activity, electrical power generation/storage as well as in scientific experiment and manufacturing processes. The Electrolysis Performance Improvement Concept Study (EPICS) flight experiment described herein is sponsored by NASA Headquarters as a part of the In-Space Technology Experiment Program (IN-STEP). The objective of the EPICS is to further contribute to the improvement of the SEF technology, specifially by demonstrating and validating the SFE electromechanical process in microgravity as well as investigating perrformance improvements projected possible in a microgravity environment. This paper defines the experiment objective and presents the results of the preliminary design of the EPICS. The experiment will include testing three subscale self-contained SFE units: one containing baseline components, and two units having variations in key component materials. Tests will be conducted at varying current and thermal condition.

Study on the Strain Hardening Behaviors of TWIP/TRIP Steels

NASA Astrophysics Data System (ADS)

Huang, T. T.; Dan, W. J.; Zhang, W. G.

2017-10-01

Due to the complex coupling of twinning-induced plasticity (TWIP), transformation-induced plasticity (TRIP), and dislocation glide in TWIP/TRIP steels, it is difficult as well as essential to build a comprehensive strain hardening model to describe the interactions between different deformation mechanisms ( i.e., deformation twinning, martensitic transformation, and dislocation glide) and the resulted strain hardening behaviors. To address this issue, a micromechanical model is established in this paper to predict the deformation process of TWIP/TRIP steels considering both TWIP and TRIP effects. In the proposed model, the generation of deformation twinning and martensitic transformation is controlled by the stacking fault energy (SFE) of the material. In the thermodynamic calculation of SFE, deformation temperature, chemical compositions, microstrain, and temperature rise during deformation are taken into account. Varied by experimental results, the developed model can predict the stress-strain response and strain hardening behaviors of TWIP/TRIP steels precisely. In addition, the improved strength and enhanced strain hardening in Fe-Mn-C TWIP/TRIP steels due to the increased carbon content is also analyzed, which consists with literature.

A thermo-mechanical correlation with driving forces for hcp martensite and twin formations in the Fe–Mn–C system exhibiting multicomposition sets

PubMed Central

Nakano, Jinichiro

2013-01-01

The thermodynamic properties of the Fe–Mn–C system were investigated by using an analytical model constructed by a CALPHAD approach. The stacking fault energy (SFE) of the fcc structure with respect to the hcp phase was always constant at T0, independent of the composition and temperature when other related parameters were assumed to be constant. Experimental limits for the thermal hcp formation and the mechanical (deformation-induced) hcp formation were separated by the SFE at T0. The driving force for the fcc to hcp transition, defined as a dimensionless value –dGm/(RT), was determined in the presence of Fe-rich and Mn-rich composition sets in each phase. Carbon tended to partition to the Mn-rich phase rather than to the Fe-rich phase for the compositions studied. The results obtained revealed a thermo-mechanical correlation with empirical yield strength, maximum true stress and maximum true strain. The proportionality between thermodynamics and mechanical properties is discussed. PMID:27877555

Importance of sulfide interaction with iron as regulator of the microbial community in biogas reactors and its effect on methanogenesis, volatile fatty acids turnover, and syntrophic long-chain fatty acids degradation.

PubMed

Shakeri Yekta, Sepehr; Ziels, Ryan M; Björn, Annika; Skyllberg, Ulf; Ejlertsson, Jörgen; Karlsson, Anna; Svedlund, Matilda; Willén, Magnus; Svensson, Bo H

2017-05-01

The inhibitory effects of sulfide on microbial processes during anaerobic digestion have been widely addressed. However, other effects of sulfide are less explored, given that sulfide is a potential sulfur source for microorganisms and its high reactivity triggers a suit of abiotic reactions. We demonstrated that sulfide interaction with Fe regulates the dynamics and activities of microbial community during anaerobic digestion. This was manifested by the S:Fe molar ratio, whose increase adversely influenced the acetoclastic methanogens, Methanosaeta, and turnover of acetate. Dynamics of hydrogenotrophic methanogens, Methanoculleus and Methanobrevibacter, were presumably influenced by sulfide-induced changes in the partial pressure of hydrogen. Interestingly, conversion of the long-chain fatty acid (LCFA), oleate, to methane was enhanced together with the abundance of LCFA-degrading, β-oxidizing Syntrophomonas at an elevated S:Fe molar ratio. The results suggested that sulfur chemical speciation is a controlling factor for microbial community functions in anaerobic digestion processes. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Plasma-modified graphene nanoplatelets and multiwalled carbon nanotubes as fillers for advanced rubber composites

NASA Astrophysics Data System (ADS)

Sicinski, M.; Gozdek, T.; Bielinski, D. M.; Szymanowski, H.; Kleczewska, J.; Piatkowska, A.

2015-07-01

In modern rubber industry, there still is a room for new fillers, which can improve the mechanical properties of the composites, or introduce a new function to the material. Modern fillers like carbon nanotubes or graphene nanoplatelets (GnP), are increasingly applied in advanced polymer composites technology. However, it might be hard to obtain a well dispersed system for such systems. The polymer matrix often exhibits higher surface free energy (SFE) level with the filler, which can cause problems with polymer-filler interphase adhesion. Filler particles are not wet properly by the polymer, and thus are easier to agglomerate. As a consequence, improvement in the mechanical properties is lower than expected. In this work, multi-walled carbon nanotubes (MWCNT) and GnP surface were modified with low-temperature plasma. Attempts were made to graft some functionalizing species on plasma-activated filler surface. The analysis of virgin and modified fillers’ SFE was carried out. MWCNT and GnP rubber composites were produced, and ultimately, their morphology and mechanical properties were studied.

A thermo-mechanical correlation with driving forces for hcp martensite and twin formations in the Fe–Mn–C system exhibiting multicomposition sets

DOE PAGES

Nakano, Jinichiro

2013-03-15

Thermodynamic properties of the Fe-Mn-C system were investigated by using an analytical model constructed by a CALPHAD approach. Stacking fault energy (SFE) of the fcc structure with respect to the hcp phase was always constant at T 0, independent of composition and temperature when the other related parameters were assumed to be constant. Experimental limits for the thermal hcp formation and the mechanical (deformation-induced) hcp formation were separated by the SFE at T 0. The driving force for the fcc to hcp transition, defined as a dimensionless value –dG m/(RT), was determined in the presence of Fe-rich and Mn-rich compositionmore » sets in each phase. Carbon tended to partition to the Mn-rich phase rather than to the Fe-rich phase for the studied compositions. The obtained results revealed a thermo-mechanical correlation with empirical yield strength, maximum true stress and maximum true strain. The proportionality between thermodynamics and mechanical properties is discussed.« less

Humus soil as a critical driver of flora conversion on karst rock outcrops.

PubMed

Zhu, Xiai; Shen, Youxin; He, Beibei; Zhao, Zhimeng

2017-10-03

Rock outcrop is an important habitat supporting plant communities in karst landscape. However, information on the restoration of higher biotic populations on outcrops is limited. Here, we investigated the diversity, biomass changes of higher vascular plants (VP) and humus soil (HS) on karst outcrops during a restoration process. We surveyed VP on rock outcrops and measured HS reserved by various rock microhabitats in a rock desertification ecosystem (RDE), an anthropogenic forest ecosystem (AFE), and a secondary forest ecosystem (SFE) in Shilin County, southwest China. HS metrics (e.g. quantity and nutrients content) and VP metrics (e.g. richness, diversity and biomass) were higher at AFE than at RDE, but lower than at SFE, suggesting that the restoration of soil subsystem vegetation increased HS properties and favored the succession of VP on rock outcrops. There was significantly positive correlation between VP metrics and HS amount, indicating that the succession of VP was strongly affected by availability and heterogeneity of HS in various rock microhabitats. Thus, floral succession of rock subsystem was slow owing to the limited resources on outcrops, although the vegetation was restored in soil subsystem.

Management of clinically non-functioning pituitary adenoma.

PubMed

Chanson, Philippe; Raverot, Gerald; Castinetti, Frédéric; Cortet-Rudelli, Christine; Galland, Françoise; Salenave, Sylvie

2015-07-01

Clinically NFPA is currently the preferred term for designing all the pituitary adenomas which are not hormonally active (in other words, not associated with clinical syndromes such as amenorrhea-galactorrhea in the context of prolactinomas, acromegaly, Cushing's disease or hyperthyroidism secondary to TSH-secreting adenomas). They account for 15-30% of pituitary adenomas. Diagnosis is usually made either in the context of mass effect due to a macroadenoma or, increasingly, fortuitously during imaging performed for some unrelated purpose; the latter case is known as pituitary incidentaloma. Surgery is indisputably indicated in case of tumoral syndrome, but other aspects of NFPA (hormonal work-up, follow-up, and especially postoperative follow-up, management of remnant or recurrence, the special case of incidentaloma, or apoplexy) remain controversial. The French Endocrinology Society (SFE) therefore set up an expert working group of endocrinologists, neurosurgeons, ophthalmologists, neuroradiologists, pathologists and biologists to draw up guidelines, at the 2012 SFE Congress in Toulouse, France. The present article presents the guidelines suggested by this group of French-speaking experts. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

The bacterial adhesion on and the cytotoxicity of various dental cements used for implant-supported fixed restorations.

PubMed

Winkler, Cornelia; Schäfer, Lina; Felthaus, Oliver; Allerdings, Juri; Hahnel, Sebastian; Behr, Michael; Bürgers, Ralf

2014-05-01

Bacterial adhesion on and cytotoxicity of eight luting agents used for implant-supported restorations were investigated. Surface roughness (Ra), surface free energy (SFE) values and three-dimensional images by atomic-force microscopy of circular specimens were determined. Bacterial suspensions of Streptococcus sanguinis and Streptococcus epidermidis were incubated at 37°C for 2 h. Adhering bacteria were examined with fluorescence dye CytoX-Violet, stained with 4',6-diamidino-2-phenylindole (DAPI) and visualized by fluorescence-microscopy. Cytotoxicity-testing was done with WST-1-tests (water soluble tetrazolium). No significant differences, neither with regard to Ra nor regarding SFE were determined. Adherence of S. sanguinis was less on titanium, TempBondNE and TempBond. TempBond, TempBondNE, RelyX Unicem and Implantlink Semi Classic presented low amounts of S. epidermidis. WST-testing showed high cytotoxic potential of Harvard, Aqualox, TempBondNE and TempBond. No combination of low adherent bacteria with low cytotoxicity was found. From a biological in-vitro perspective, none of the cements may be recommended for implant-supported restorations.

Bone augmentation as an adjunct to dental implant rehabilitation in patients with diabetes mellitus: A review of literature

PubMed Central

Ladha, Komal; Sharma, Ankit; Tiwari, Bhawana; Bukya, Dwaraka N

2017-01-01

The aim of the present article is to review the success of bone augmentation performed as an adjunct to dental implant rehabilitation in patients with diabetes mellitus. A literature review was conducted in PubMed on this topic, which yielded a total of 102 publications. For inclusion, publications had to be human studies, written in English language and should report on the success of bone augmentation as an adjunct to dental implant rehabilitation in diabetic patients. After screening the titles and abstracts, 11 full texts publications were obtained, of which seven were included in the review. These studies provided data on various bone augmentation techniques such as sinus floor elevation (SFE), guided bone regeneration (GBR), and onlay bone grafting. Even though the current review revealed that there are not many studies reporting data relevant to the analyzed topic, the data obtained suggests that; (1) staged GBR technique should be considered more feasible and predictable for bone augmentation, (2) clinicians must take meticulous care when planning and conducting SFE, and (3) block bone augmentation technique should be avoided. PMID:29386810

Functional Ginger Extracts from Supercritical Fluid Carbon Dioxide Extraction via In Vitro and In Vivo Assays: Antioxidation, Antimicroorganism, and Mice Xenografts Models

PubMed Central

Lee, Chih-Chen; Chiou, Li-Yu; Wang, Jheng-Yang; Chou, Sin-You; Lan, John Chi-Wei; Huang, Tsi-Shu; Huang, Kuo-Chuan

2013-01-01

Supercritical fluid carbon dioxide extraction technology was developed to gain the active components from a Taiwan native plant, Zingiber officinale (ginger). We studied the biological effects of ginger extracts via multiple assays and demonstrated the biofunctions in each platform. Investigations of ginger extracts indicated antioxidative properties in dose-dependant manners on radical scavenging activities, reducing powers and metal chelating powers. We found that ginger extracts processed moderate scavenging values, middle metal chelating levels, and slight ferric reducing powers. The antibacterial susceptibility of ginger extracts on Staphylococcus aureus, Streptococcus sobrinus, S. mutans, and Escherichia coli was determined with the broth microdilution method technique. The ginger extracts had operative antimicroorganism potentials against both Gram-positive and Gram-negative bacteria. We further discovered the strong inhibitions of ginger extracts on lethal carcinogenic melanoma through in vivo xenograft model. To sum up, the data confirmed the possible applications as medical cosmetology agents, pharmaceutical antibiotics, and food supplements. PMID:23983624

Comparison of the bioavailability of elemental waste laden soils using in vivo and in vitro analytical methodology and refinement of exposure/dose models. 1998 annual progress report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lioy, P.J.; Gallo, M.; Georgopoulos, P.

1998-06-01

'The authors hypotheses are: (1) the more closely the synthetic, in vitro, extractant mimics the extraction properties of the human digestive bio-fluids, the more accurate will be the estimate of an internal dose; (2) performance can be evaluated by in vivo studies with a rat model and quantitative examination of a mass balance, calculation and dose estimates from model simulations for the in vitro and in vivo system; and (3) the concentration of the elements Pb, Cd, Cr and selected Radionuclides present in the bioavailable fraction obtained with a synthetic extraction system will be a better indicator of contaminant ingestionmore » from a contaminated soil because it represents the portion of the mass which can yield exposure, uptake and then the internal dose to an individual. As of April 15, 1998, they have made significant progress in the development of a unified approach to the examination of bioavailability and bioaccessibility of elemental contamination of soils for the ingestion route of exposure. This includes the initial characterization of the soil, in vitro measurements of bioaccessibility, and in vivo measurements of bioavailability. They have identified the basic chemical and microbiological characteristics of waste laden soils. These have been used to prioritize the soils for potential mobility of the trace elements present in the soil. Subsequently they have employed a mass balance technique, which for the first time tracked the movement and distribution of elements through an in vitro or in vivo experimental protocol to define the bioaccessible and the bioavailable fractions of digested soil. The basic mass balance equation for the in vitro system is: MT = MSGJ + MIJ + MR. where MT is the total mass extractable by a specific method, MSGJ, is the mass extracted by the saliva and the gastric juices, MIJ is the mass extracted by the intestinal fluid, and MR is the unextractable portion of the initial mass. The above is based upon the use of a synthetic digestive bio-fluids model that includes the saliva, gastric juices, and intestinal fluids. The system has been devised to sequentially extract elements from soil by starting with an extraction by the saliva and carrying the entire mixture to the subsequent bio-fluids for further extraction. The residence time of the soil in each extractant and the liquid to mass ratio in the gastric juices are based upon typical values known for the human digestive system. Experiments were conducted to examine the sensitivity of the extractions to changes in these major variables. The results indicated the lack of significant extraction after 2 h of residence in gastric fluid. The range of variation of the liquid to mass ratio was element dependent over the interval 100:1 and 5,000:1. The final values used for the extraction protocol were: 2 h residence time , and a ratio of 1,000:1. Details of the chemical composition of the extraction protocol are found in Hamel, 1998.'« less

The Molecular Design of High-Performance Carbon Materials

DTIC Science & Technology

2008-06-30

Thies MC. Control of mesophase pitch properties by supercritical fluid extraction. Carbon 1998; 36(7-8):953-61. 7] Zhuang M, Gast K, Thies MC...pitch with supercritical toluene. J Supercrit Fluids 1991; 4(1):7-14. 16] Herod AA, Bartle KD, Kandiyoti R. Characterization of heavy...MALDI, mass spectrometry, mesophase, extraction, supercritical , fractionation. 16. SECURITY CLASSIFICATION OF: a. REPORT u b. ABSTRACT u c. THIS

Magneto-structural correlations in a family of Fe(II)Re(IV)(CN)2 single-chain magnets: density functional theory and ab initio calculations.

PubMed

Zhang, Yi-Quan; Luo, Cheng-Lin; Wu, Xin-Bao; Wang, Bing-Wu; Gao, Song

2014-04-07

Until now, the expressions of the anisotropic energy barriers Δξ and ΔA, using the uniaxial magnetic anisotropy D, the intrachain coupling strength J, and the high-spin ground state S for single-chain magnets (SCMs) in the intermediate region between the Ising and the Heisenberg limits, were unknown. To explore this relationship, we used density functional theory and ab initio methods to obtain expressions of Δξ and ΔA in terms of D, J, and S of six R4Fe(II)-Re(IV)Cl4(CN)2 (R = diethylformamide (1), dibutylformamide (2), dimethylformamide (3), dimethylbutyramide (4), dimethylpropionamide (5), and diethylacetamide (6)) SCMs in the intermediate region. The ΔA value for compounds 1-3 was very similar to the magnetic anisotropic energy of a single Fe(II), while the value of Δξ was predicted using the exchange interaction of Fe(II) with the neighboring Re(IV), which could be expressed as 2JSReSFe. Similar to compounds 1-3, the anisotropy energy barrier ΔA of compounds 4 and 5 was also equal to (Di - Ei)SFe(2), but the correlation energy Δξ was closely equal to 2JSReSFe(cos 98.4 - cos 180) due to the reversal of the spins on the opposite Fe(II). For compound 6, one unit cell of Re(IV)Fe(II) was regarded as a domain wall since it had two different Re(IV)-Fe(II) couplings. Thus, the Δξ of compound 6 was expressed as 4J″SRe1Fe1SRe2Fe2, where J″ was the coupling constant of the neighboring unit cells of Re1Fe1 and Re2Fe2, and ΔA was equal to the anisotropic energy barrier of one domain wall given by DRe1Fe1(S(2)Re1Fe1 - 1/4).

Anomalously Low pCO2 Measured in the San Francisco Estuary

NASA Astrophysics Data System (ADS)

Fuller, J. R.; Wilkerson, F.; Parker, A. E.; Marchi, A.

2008-12-01

Estuaries have been identified as potential net sources of CO2 to the atmosphere. Bacterial respiration of organic matter entering the estuary leads to supersaturated levels of pCO2. The southern embayment of the San Francisco Estuary (SFE) is no exception due in part to wastewater treatment practices. Persistently high levels of pCO2 between 600 and 1000 μatm have been reported for this embayment by the U.S. Geological Survey over the period 1976-1980 and more recently (2007-2008) by the authors. However, both studies also found notable exceptions to the high pCO2 levels during the spring phytoplankton bloom. An average level of 375 μatm, slightly above the contemporary atmospheric level, was observed during an April 1980 transect. Our recent measurements over the same transect have observed an even greater drawdown of pCO2 to as low as 175 μatm. In addition the pCO2 drawdown persisted from early March 2008 until the end of May. These anomalously low levels correspond directly with an algal bloom as evidenced by high concentrations of chlorophyll a and supersaturated dissolved oxygen. To our knowledge these are the lowest levels reported for the SFE and they indicate that portions of the estuary are a sink for atmospheric CO2 during bloom conditions. The hydrology of the southern embayment is dominated at times by the input of wastewater which is often treated to the advanced secondary level with inorganic nitrate as the product. This possibly contributes to a healthy estuarine algal population that helps to maintain current pCO2 levels in the SFE to those of 30 years ago despite significant urban growth around the estuary over that period. These findings have major implications both to estuarine management and to estimates of the estuarine component in global air-sea CO2 exchange

The role of molecular gas in galaxy transition in compact groups

NASA Astrophysics Data System (ADS)

Lisenfeld, U.; Alatalo, K.; Zucker, C.; Appleton, P. N.; Gallagher, S.; Guillard, P.; Johnson, K.

2017-11-01

Compact groups (CGs) provide an environment in which interactions between galaxies and with the intra-group medium enable and accelerate galaxy transitions from actively star forming to quiescent. Galaxies in transition from active to quiescent can be selected, by their infrared (IR) colors, as canyon or infrared transition zone (IRTZ) galaxies. We used a sample of CG galaxies with IR data from the Wide Field Infrared Survey Explorer (WISE) allowing us to calculate the stellar mass and star formation rate (SFR) for each galaxy. Furthermore, we present new CO(1-0) data for 27 galaxies and collect data from the literature to calculate the molecular gas mass for a total sample of 130 galaxies. This data set allows us to study the difference in the molecular gas fraction (Mmol/M∗) and star formation efficiency (SFE = SFR/Mmol) between active, quiescent, and transitioning (I.e., canyon and IRTZ) galaxies. We find that transitioning galaxies have a mean molecular gas fraction and a mean SFE that are significantly lower than those of actively star-forming galaxies. The molecular gas fraction is higher than that of quiescent galaxies, whereas the SFE is similar. These results indicate that the transition from actively star-forming to quiescent in CG galaxies goes along with a loss of molecular gas, possibly due to tidal forces exerted from the neighboring galaxies or a decrease in the gas density. In addition, the remaining molecular gas loses its ability to form stars efficiently, possibly owing to turbulence perturbing the gas,as seen in other, well-studied examples such as Stephan's Quintet and HCG 57. Thus, the amount and properties of molecular gas play a crucial role in the environmentally driven transition of galaxies from actively star forming to quiescent. Full Table 2 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/607/A110

PEEK surface treatment effects on tensile bond strength to veneering resins.

PubMed

Stawarczyk, Bogna; Jordan, Peter; Schmidlin, Patrick R; Roos, Malgorzata; Eichberger, Marlis; Gernet, Wolfgang; Keul, Christine

2014-11-01

Polyetheretherketone (PEEK) can be used as a framework material for fixed dental prostheses. However, information about the durable bond to veneering resins is still scarce. The purpose of this study was to investigate the effect of chemical treatments of PEEK on tensile bond strength (TBS) to veneering resins with special emphasis on surface free energy (SFE) and surface roughness (SR). Seven-hundred fifty PEEK specimens were fabricated and divided into the following 3 pretreatment groups (n=250/group): etching with sulfuric acid for 60 seconds, etching with piranha acid for 30 seconds, and an unetched control. After pretreatment, SFE was determined by using contact angle measurements and SR with a profilometer (n=10/group). The topography of pretreated PEEK surfaces was examined with scanning electron microscopy. Remaining specimens (n=240 per group) were conditioned with visio.link or Signum PEEK Bond, or were left untreated as the control group. Half of each group was veneered with Sinfony or VITA VM LC (n=40/group), and TBS was measured after storage in distilled water at 37°C for either 24 hours or 60 days. Data were analyzed by 4-way and 1-way ANOVA followed by the Scheffé post hoc test and chi-square test (α=.05). PEEK specimens etched with sulfuric acid resulted in higher SFE and SR than specimens without pretreatment or etching with piranha acid. Etching with sulfuric acid or piranha acid led to no general recommendations with respect to TBS. Conditioning with visio.link or Signum PEEK Bond significantly increased the TBS (P<.001). PEEK veneered with Sinfony showed significantly higher TBS values than those veneered with VITA VM LC (P<.001). Sufficient TBS for bonding to veneering resin can only be achieved when additional adhesive materials were applied. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Multi-fluid renewable geo-energy systems and methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buscheck, Thomas A.

A geo-energy production method for extracting thermal energy from a reservoir formation. A production well extracts brine from the reservoir formation. A plurality of working fluid injection ("WFI") wells may be arranged proximate to the production well to at least partially circumscribe the production well. A plurality of brine production ("BP") wells may be arranged in a vicinity of the WFI wells to at least partially circumscribe the WFI wells. A working fluid is injected into the WFI wells to help drive a flow of the brine up through the production and BP wells, together with at least a portionmore » of the injected working fluid. Parasitic-load time-shifting and to storing of excess solar thermal energy may also be performed.« less

River flow and ammonium discharge determine spring phytoplankton blooms in an urbanized estuary

NASA Astrophysics Data System (ADS)

Dugdale, Richard; Wilkerson, Frances; Parker, Alexander E.; Marchi, Al; Taberski, Karen

2012-12-01

Nutrient loadings to urbanized estuaries have increased over the past decades in response to population growth and upgrading to secondary sewage treatment. Evidence from the San Francisco Estuary (SFE) indicates that increased ammonium (NH4) loads have resulted in reduced primary production, a counter-intuitive finding; the NH4 paradox. Phytoplankton uptake of nitrate (NO3), the largest pool of dissolved inorganic nitrogen, is necessary for blooms to occur in SFE. The relatively small pool of ambient NH4, by itself insufficient to support a bloom, prevents access to NO3 and bloom development. This has contributed to the current rarity of spring phytoplankton blooms in the northern SFE (Suisun Bay), in spite of high inorganic nutrient concentrations, improved water transparency and seasonally low biomass of bivalve grazers. The lack of blooms has likely contributed to deleterious bottom-up impacts on estuarine fish. This bloom suppression may also occur in other estuaries that receive large amounts of anthropogenic NH4. In 2010 two rare diatom blooms were observed in spring in Suisun Bay (followed by increased abundances of copepods and pelagic fish), and like the prior bloom observed in 2000, chlorophyll accumulated after NH4 concentrations were decreased. In 2010, low NH4 concentrations were apparently due to a combination of reduced NH4 discharge from a wastewater treatment plant and increased river flow. To understand the interactions of river flow, NH4 discharge and bloom initiation, a conceptual model was constructed with three criteria; 1) NH4 loading must not exceed the capacity of the phytoplankton to assimilate the inflow of NH4, 2) the NH4 concentration must be ≤4 μmol L-1 to enable phytoplankton NO3 uptake, 3) the dilution rate of phytoplankton biomass set by river flow must not exceed the phytoplankton growth rate to avoid "washout". These criteria were determined for Suisun Bay; with sufficient irradiance and present day discharge of 15 tons NH4-N d-1at the upstream wastewater treatment plant (WTP). The loading criterion requires phytoplankton NH4 uptake to exceed 1.58 mmol m-2 d-1; the concentration criterion requires river flow >800 m3 s-1 at the WTP for sufficient NH4 dilution and the washout criterion requires river flow at Suisun Bay <1100 m3 s-1. The model and criteria are used to suggest how a reduction in anthropogenic NH4, either by reduced discharge or increased dilution (river flow), could be used as a management tool to restore pre-existing productivity in the SFE and similarly impacted estuaries.

High resolution melt curve analysis based on methylation status for human semen identification.

PubMed

Fachet, Caitlyn; Quarino, Lawrence; Karnas, K Joy

2017-03-01

A high resolution melt curve assay to differentiate semen from blood, saliva, urine, and vaginal fluid based on methylation status at the Dapper Isoform 1 (DACT1) gene was developed. Stains made from blood, saliva, urine, semen, and vaginal fluid were obtained from volunteers and DNA was isolated using either organic extraction (saliva, urine, and vaginal fluid) or Chelex ® 100 extraction (blood and semen). Extracts were then subjected to bisulfite modification in order to convert unmethylated cytosines to uracil, consequently creating sequences whose amplicons have melt curves that vary depending on their initial methylation status. When primers designed to amplify the promoter region of the DACT1 gene were used, DNA from semen samples was distinguishable from other fluids by a having a statistically significant lower melting temperature. The assay was found to be sperm-significant since semen from a vasectomized man produced a melting temperature similar to the non-semen body fluids. Blood and semen stains stored up to 5 months and tested at various intervals showed little variation in melt temperature indicating the methylation status was stable during the course of the study. The assay is a more viable method for forensic science practice than most molecular-based methods for body fluid stain identification since it is time efficient and utilizes instrumentation common to forensic biology laboratories. In addition, the assay is advantageous over traditional presumptive chemical methods for body fluid identification since results are confirmatory and the assay offers the possibility of multiplexing which may test for multiple body fluids simultaneously.

Evaluation of CO 2 -Fluid-Rock Interaction in Enhanced Geothermal Systems: Field-Scale Geochemical Simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pan, Feng; McPherson, Brian J.; Kaszuba, John

Recent studies suggest that using supercritical CO 2 (scCO 2 ) instead of water as a heat transmission fluid in Enhanced Geothermal Systems (EGS) may improve energy extraction. While CO 2 -fluid-rock interactions at “typical” temperatures and pressures of subsurface reservoirs are fairly well known, such understanding for the elevated conditions of EGS is relatively unresolved. Geochemical impacts of CO 2 as a working fluid (“CO 2 -EGS”) compared to those for water as a working fluid (H 2 O-EGS) are needed. The primary objectives of this study are (1) constraining geochemical processes associated with CO 2 -fluid-rock interactions undermore » the high pressures and temperatures of a typical CO 2 -EGS site and (2) comparing geochemical impacts of CO 2 -EGS to geochemical impacts of H 2 O-EGS. The St. John’s Dome CO 2 -EGS research site in Arizona was adopted as a case study. A 3D model of the site was developed. Net heat extraction and mass flow production rates for CO 2 -EGS were larger compared to H 2 O-EGS, suggesting that using scCO 2 as a working fluid may enhance EGS heat extraction. More aqueous CO 2 accumulates within upper- and lower-lying layers than in the injection/production layers, reducing pH values and leading to increased dissolution and precipitation of minerals in those upper and lower layers. Dissolution of oligoclase for water as a working fluid shows smaller magnitude in rates and different distributions in profile than those for scCO 2 as a working fluid. It indicates that geochemical processes of scCO 2 -rock interaction have significant effects on mineral dissolution and precipitation in magnitudes and distributions.« less

The effect of pigeon yolk sac fluid on the growth behavior of calcium carbonate crystals.

PubMed

Song, Juan; Cheng, Haixia; Shen, Xinyu; Tong, Hua

2015-03-01

Previous experiments have proved that thermodynamically unstable calcium carbonate vaterite can exist for long periods in the yolk sac of a pigeon embryo. The aim of this article was to demonstrate the effect of in vitro mineralization of yolk sac fluid on calcium carbonate by direct precipitation. Experiments were conducted using pigeon yolk sac fluid and using lecithin extracted from pigeon yolk sac fluid as a control to investigate the regulating effects of the organic components in the embryo on the formation of the calcium carbonate precipitate. Multiple characterization methods were employed to study the various morphological patterns, sizes, crystal growth, and crystal phase transformations of the calcium carbonate precipitates as regulated by the yolk sac fluid extracted at different stages of incubation. The experimental results demonstrate that as the incubation proceeds towards the later stages, the composition and environmental features of the yolk sac fluid become more favorable for the formation of relatively unstable calcium carbonate phases with high energies of the vaterite state. The experiments conducted with extracted lecithin as the template for crystal growth yielded similar results. A large amount of organic molecules with polar functional groups carried by the yolk sac fluid have strong effects and can both initially induce the crystallization and regulate the aggregation of calcium carbonate. Furthermore, this regulation process is found to be closely related to the lecithin contained in yolk sac fluid. These observations confirm the changes in yolk sac fluid composition during incubation have significant effects on the production of vaterite, which implicates the calcium transport during embryo growth. © 2015 Poultry Science Association Inc.

Evaluation of CO 2 -Fluid-Rock Interaction in Enhanced Geothermal Systems: Field-Scale Geochemical Simulations

DOE PAGES

Pan, Feng; McPherson, Brian J.; Kaszuba, John

2017-01-01

Recent studies suggest that using supercritical CO 2 (scCO 2 ) instead of water as a heat transmission fluid in Enhanced Geothermal Systems (EGS) may improve energy extraction. While CO 2 -fluid-rock interactions at “typical” temperatures and pressures of subsurface reservoirs are fairly well known, such understanding for the elevated conditions of EGS is relatively unresolved. Geochemical impacts of CO 2 as a working fluid (“CO 2 -EGS”) compared to those for water as a working fluid (H 2 O-EGS) are needed. The primary objectives of this study are (1) constraining geochemical processes associated with CO 2 -fluid-rock interactions undermore » the high pressures and temperatures of a typical CO 2 -EGS site and (2) comparing geochemical impacts of CO 2 -EGS to geochemical impacts of H 2 O-EGS. The St. John’s Dome CO 2 -EGS research site in Arizona was adopted as a case study. A 3D model of the site was developed. Net heat extraction and mass flow production rates for CO 2 -EGS were larger compared to H 2 O-EGS, suggesting that using scCO 2 as a working fluid may enhance EGS heat extraction. More aqueous CO 2 accumulates within upper- and lower-lying layers than in the injection/production layers, reducing pH values and leading to increased dissolution and precipitation of minerals in those upper and lower layers. Dissolution of oligoclase for water as a working fluid shows smaller magnitude in rates and different distributions in profile than those for scCO 2 as a working fluid. It indicates that geochemical processes of scCO 2 -rock interaction have significant effects on mineral dissolution and precipitation in magnitudes and distributions.« less

Subcritical Fluid Extraction of Chinese Quince Seed: Optimization and Product Characterization.

PubMed

Wang, Li; Wu, Min; Liu, Hua-Min; Ma, Yu-Xiang; Wang, Xue-De; Qin, Guang-Yong

2017-03-25

Chinese quince seed (CQS) is an underutilized oil source and a potential source of unsaturated fatty acids and α-tocopherol-rich oil. Subcritical fluid (SCF) extraction is executed at lower pressures and temperatures than the pressures and temperatures used in supercritical fluid extraction. However, no studies on the SCF extraction of CQS oil are reported. Therefore, the objective of this study was to evaluate the use of SCF for the extraction of CQS oil and to compare the use of SCF with the classical Soxhlet (CS) and supercritical CO₂ (SC-CO₂) extraction methods. Response surface methodology (RSM) was used to investigate the extraction conditions: temperature (45-65 °C), time (30-50 min), and solvent/solid ratio (5-15 mL/g). The optimization results showed that the highest yield (27.78%) was obtained at 56.18 °C, 40.20 min, and 12.57 mL/g. The oil extracted by SCF had a higher unsaturated fatty acid content (86.37%-86.75%), higher α-tocopherol content (576.0-847.6 mg/kg), lower acid value (3.97 mg/g), and lower peroxide value (0.02 meq O₂/kg) than extractions using CS and SC-CO 2 methods. The SCF-defatted meal of oilseed exhibited the highest nitrogen solubility index (49.64%) and protein dispersibility index (50.80%), demonstrating that SCF extraction was a promising and efficient technique as an alternative to CS and SC-CO 2 methods, as very mild operating conditions and an eco-friendly solvent can be used in the process with maximum preservation of the quality of the meal.

Single-step preparation of selected biological fluids for the high performance liquid chromatographic analysis of fat-soluble vitamins and antioxidants.

PubMed

Lazzarino, Giacomo; Longo, Salvatore; Amorini, Angela Maria; Di Pietro, Valentina; D'Urso, Serafina; Lazzarino, Giuseppe; Belli, Antonio; Tavazzi, Barbara

2017-12-08

Fat-soluble vitamins and antioxidants are of relevance in health and disease. Current methods to extract these compounds from biological fluids mainly need use of multi-steps and multi organic solvents. They are time-consuming and difficult to apply to treat simultaneously large sample number. We here describe a single-step, one solvent extraction of fat-soluble vitamins and antioxidants from biological fluids, and the chromatographic separation of all-trans-retinoic acid, 25-hydroxycholecalciferol, all-trans-retinol, astaxanthin, lutein, zeaxanthin, trans-β-apo-8'-carotenal, γ-tocopherol, β-cryptoxanthin, α-tocopherol, phylloquinone, lycopene, α-carotene, β-carotene and coenzyme Q 10 . Extraction is obtained by adding one volume of biological fluid to two acetonitrile volumes, vortexing for 60s and incubating for 60min at 37°C under agitation. HPLC separation occurs in 30min using Hypersil C18, 100×4.6mm, 5μm particle size column, gradient from 70% methanol+30% H 2 O to 100% acetonitrile, flow rate of 1.0ml/min and 37°C column temperature. Compounds are revealed using highly sensitive UV-VIS diode array detector. The HPLC method suitability was assessed in terms of sensitivity, reproducibility and recovery. Using the present extraction and chromatographic conditions we obtained values of the fat-soluble vitamins and antioxidants in serum from 50 healthy controls similar to those found in literature. Additionally, the profile of these compounds was also measured in seminal plasma from 20 healthy fertile donors. Results indicate that this simple, rapid and low cost sample processing is suitable to extract fat-soluble vitamins and antioxidants from biological fluids and can be applied in clinical and nutritional studies. Copyright © 2017 Elsevier B.V. All rights reserved.

Oral bioaccessibility and human exposure to anthropogenic and geogenic mercury in urban, industrial and mining areas.

PubMed

Rodrigues, S M; Coelho, C; Cruz, N; Monteiro, R J R; Henriques, B; Duarte, A C; Römkens, P F A M; Pereira, E

2014-10-15

The objective of this study was to characterize the link between bioaccessibility and fractionation of mercury (Hg) in soils and to provide insight into human exposure to Hg due to inhalation of airborne soil particles and hand-to-mouth ingestion of Hg-bearing soil. Mercury in soils from mining, urban and industrial areas was fractionated in organometallic forms; mobile; semi-mobile; and non-mobile forms as well as HCl-extractable Hg. The in vitro bioaccessibility of Hg was obtained by extracting soils with (1) a simulated human gastric fluid (pH1.5), and (2) a simulated human lung fluid (pH7.4). Total soil Hg concentrations ranged from 0.72 to 1.8 mg kg(-1) (urban areas), 0.28 to 94 mg kg(-1) (industrial area) and 0.92 to 37 mg kg(-1) (mining areas). Both organometallic Hg as well as 0.1M HCl extractable Hg were lower (<0.5% of total Hg) than Hg extracted by gastric fluid (up to 1.8% of total Hg) and lung fluid (up to 12% of total Hg). In addition, Hg extracted by lung fluid was significantly higher in urban and industrial soils (average 5.0-6.6% of total Hg) compared to mining soils. Such differences were related to levels of mobile Hg species in urban and industrial soils compared to mining soils. These results strengthen the need to measure site-specific Hg fractionation when determining Hg bioaccessibility. Results also show that ingestion and/or inhalation of Hg from soil particles can contribute up to 8% of adult total Hg intake when compared to total Hg intake via consumption of contaminated fish and animal products from contaminated areas. Copyright © 2014 Elsevier B.V. All rights reserved.

Effects of process parameters on peanut skins extract and CO2 diffusivity by supercritical fluid extraction

NASA Astrophysics Data System (ADS)

Putra, N. R.; Yian, L. N.; Nasir, H. M.; Idham, Z. Binti; Yunus, M. A. C.

2018-03-01

Peanut skins (Arachis hypogea) are an agricultural waste product which has received much attention because they contain high nutritional values and can be potentially utilized in difference industries. At present, only a few studies have been conducted to study the effects of parameters on the peanut skins oil extraction. Therefore, this study aimed to determine the best extraction condition in order to obtain the highest extract yield using supercritical carbon dioxide (SC-CO2) with co-solvent Ethanol as compared to Soxhlet extraction method. Diffusivity of carbon dioxide in supercritical fluid extraction was determined using Crank model. The mean particle size used in this study was 425 µm. The supercritical carbon dioxide was performed at temperature (40 – 70 °C), flow rate of co-solvent ethanol (0 - 7.5% Vethanol/Vtotal), and extraction pressure (10 – 30 MPa) were used in this studies. The results showed that the percentage of oil yields and effective diffusivity increase as the pressure, rate of co-solvent, and temperature increased.

Improvement and automation of a real-time PCR assay for vaginal fluids.

PubMed

De Vittori, E; Giampaoli, S; Barni, F; Baldi, M; Berti, A; Ripani, L; Romano Spica, V

2016-05-01

The identification of vaginal fluids is crucial in forensic science. Several molecular protocols based on PCR amplification of mfDNA (microflora DNA) specific for vaginal bacteria are now available. Unfortunately mfDNA extraction and PCR reactions require manual optimization of several steps. The aim of present study was the verification of a partial automatization of vaginal fluids identification through two instruments widely diffused in forensic laboratories: EZ1 Advanced robot and Rotor Gene Q 5Plex HRM. Moreover, taking advantage of 5-plex thermocycler technology, the ForFluid kit performances were improved by expanding the mfDNA characterization panel with a new bacterial target for vaginal fluids and with an internal positive control (IPC) to monitor PCR inhibition. Results underlined the feasibility of a semi-automated extraction of mfDNA using a BioRobot and demonstrated the analytical improvements of the kit. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Generation of monoclonal antibodies and development of an immunofluorometric assay for the detection of CUZD1 in tissues and biological fluids.

PubMed

Farkona, Sofia; Soosaipillai, Antoninus; Filippou, Panagiota; Korbakis, Dimitrios; Serra, Stefano; Rückert, Felix; Diamandis, Eleftherios P; Blasutig, Ivan M

2017-12-01

CUB and zona pellucida-like domain-containing protein 1 (CUZD1) was identified as a pancreas-specific protein and was proposed as a candidate biomarker for pancreatic related disorders. CUZD1 protein levels in tissues and biological fluids have not been extensively examined. The purpose of the present study was to generate specific antibodies targeting CUZD1 to assess CUZD1 expression within tissues and biological fluids. Mouse monoclonal antibodies against CUZD1 were generated and used to perform immunohistochemical analyses and to develop a sensitive and specific enzyme-linked immunosorbent assay (ELISA). CUZD1 protein expression was assessed in various human tissue extracts and biological fluids and in gel filtration chromatography-derived fractions of pancreatic tissue extract, pancreatic juice and recombinant protein. Immunohistochemical staining of CUZD1 in pancreatic tissue showed that the protein is localized to the acinar cells and the lumen of the acini. Western blot analysis detected the protein in pancreatic tissue extract and pancreatic juice. The newly developed ELISA measured CUZD1 in high levels in pancreas and in much lower but detectable levels in several other tissues. In the biological fluids tested, CUZD1 expression was detected exclusively in pancreatic juice. The analysis of gel filtration chromatography-derived fractions of pancreatic tissue extract, pancreatic juice and recombinant CUZD1 suggested that the protein exists in high molecular weight protein complexes. This study describes the development of tools targeting CUZD1 protein, its tissue expression pattern and levels in several biological fluids. These new tools will facilitate future investigations aiming to delineate the role of CUZD1 in physiology and pathobiology. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Determination of vitamin K1 in powdered infant formulas, using supercritical fluid extraction and liquid chromatography with electrochemical detection.

PubMed

Schneiderman, M A; Sharma, A K; Mahanama, K R; Locke, D C

1988-01-01

Vitamin K1 (phylloquinone) is extracted from commercial soy protein-based and milk-based powdered infant formulas by using supercritical fluid extraction with CO2 at 8000 psi and 60 degrees C. Quantitative extraction requires only 15 min, and does not suffer from the problems associated with conventional solvent extraction of lipophilic materials from media such as formulas. Vitamin K1 is determined in the extracts by using reverse-phase liquid chromatography (LC) with reductive mode electrochemical detection at a silver electrode polarized at -1.1 V vs SCE. LC run time is 9 min. The minimum detectable quantity is 80 pg, and response is linear over at least 5 orders of magnitude. Recovery of vitamin K1 from a milk-based powdered formula was 95.6% with RSD of 7.4%, and from a soy protein-based product, 94.4% recovery with RSD of 6.5%.

DEVELOPMENTS IN THE SUPERCRITICAL FLUID EXTRACTION OF CHLOROPHENOXY ACID HERBICIDES FROM SOIL SAMPLES

EPA Science Inventory

Extraction of chlorophenoxy acid herbicides from soil samples with supercritical carbon dioxide as extractant and tetrabutylammonium hydroxide and methyl iodide as derivatization agents was investigated. The extraction was carried out at 400 atm and 80 C for 15 min static, follow...

Subjective Word Frequency Estimates in L1 and L2.

ERIC Educational Resources Information Center

Arnaud, Pierre J. L.

A study investigated the usefulness of non-native speakers' subjective, relative word frequency estimates as a measure of second language proficiency. In the experiment, two subjective frequency estimate (SFE) tasks, one on French and one on English, were presented to French learners of English (n=126) and American learners of French (n=87).…

A Report of Two Cases of Solid Facial Edema in Acne.

PubMed

Kuhn-Régnier, Sarah; Mangana, Joanna; Kerl, Katrin; Kamarachev, Jivko; French, Lars E; Cozzio, Antonio; Navarini, Alexander A

2017-03-01

Solid facial edema (SFE) is a rare complication of acne vulgaris. To examine the clinical features of acne patients with solid facial edema, and to give an overview on the outcome of previous topical and systemic treatments in the cases so far published. We report two cases from Switzerland, both young men with initially papulopustular acne resistant to topical retinoids. Both cases responded to oral isotretinoin, in one case combined with oral steroids. Our cases show a strikingly similar clinical appearance to the cases described by Connelly and Winkelmann in 1985 (Connelly MG, Winkelmann RK. Solid facial edema as a complication of acne vulgaris. Arch Dermatol. 1985;121(1):87), as well as to cases of Morbihan's disease that occurs as a rare complication of rosacea. Even 30 years after, the cause of the edema remains unknown. In two of the original four cases, a potential triggering factor was identified such as facial trauma or insect bites; however, our two patients did not report such occurrencies. The rare cases of solid facial edema in both acne and rosacea might hold the key to understanding the specific inflammatory pattern that creates both persisting inflammation and disturbed fluid homeostasis which can occur as a slightly different presentation in dermatomyositis, angioedema, Heerfordt's syndrome and other conditions.

Sodium-dependent transport of sugars and iodide from the cerebral venticles of the rabbit.

PubMed

Bradbury, M W; Brondsted, H E

1973-10-01

1. The objective was to discover whether the extraction of sugars and iodide from the perfused cerebral ventricles is Na(+)-dependent.2. In the ventriculo-aqueductal and ventriculo-cisternal perfusion systems in the rabbit the extraction of (14)C-labelled D-hexoses (glucose, 3-O-methyl-glucose, alpha-methyl-glucoside and galactose), (131)I(-) and (24)Na was inhibited when 82% of the Na(+) in the perfusion fluid was replaced by choline. The extraction returned to control levels when the Na(+) concentration in the perfusion fluid was returned to normal.3. Ouabain, 5 x 10(-5)M in the perfusion fluid inhibited the extraction of the above (14)C sugars and (131)I(-), but hardly affected that of [(3)H]2-deoxy-D-glucose. It enhanced the extraction of (24)Na. C.s.f. production was usually totally inhibited.4. The extraction of [(14)C]urea remained unchanged during perfusion with low Na(+) fluid or ouabain.5. Recovery from brain of [(14)C]3-O-methyl-glucose, [(3)H]2-deoxy-glucose and (131)I(-) was low while recovery of [(14)C]alpha-methyl-glucoside and (24)Na was high. On an equal weight basis recovery of [(14)C]3-O-methyl-glucose was about twelve times higher from the choroid plexus than from the brain.6. Part of the movement of (14)C sugars may be explained on basis of a Na(+)-gradient hypothesis with involvement of the Na(+) pump at the blood-c.s.f. or blood-brain barriers.7. The rate of c.s.f. production from the first three ventricles comprised about 40% of the rate from all four ventricles. The extraction of sugars, urea and cations was similar in both perfusion systems while the extraction of (131)I(-) was higher in the ventriculo-cisternal system than in the ventriculo-aqueductal system.

Silica extraction from geothermal water

DOEpatents

Bourcier, William L; Bruton, Carol J

2014-09-23

A method of producing silica from geothermal fluid containing low concentration of the silica of less than 275 ppm includes the steps of treating the geothermal fluid containing the silica by reverse osmosis treatment thereby producing a concentrated fluid containing the silica, seasoning the concentrated fluid thereby producing a slurry having precipitated colloids containing the silica, and separating the silica from the slurry.

Anthropogenic seismicity rates and operational parameters at the Salton Sea Geothermal Field.

PubMed

Brodsky, Emily E; Lajoie, Lia J

2013-08-02

Geothermal power is a growing energy source; however, efforts to increase production are tempered by concern over induced earthquakes. Although increased seismicity commonly accompanies geothermal production, induced earthquake rate cannot currently be forecast on the basis of fluid injection volumes or any other operational parameters. We show that at the Salton Sea Geothermal Field, the total volume of fluid extracted or injected tracks the long-term evolution of seismicity. After correcting for the aftershock rate, the net fluid volume (extracted-injected) provides the best correlation with seismicity in recent years. We model the background earthquake rate with a linear combination of injection and net production rates that allows us to track the secular development of the field as the number of earthquakes per fluid volume injected decreases over time.

Supercritical Fluid Extraction of Pyrrolidine Alkaloid from Leaves of Piper amalago L.

PubMed Central

Filho, L. C.; Faiões, V. S.; Cunha-Júnior, E. F.; Torres-Santos, E. C.; Cortez, D. A. G.

2017-01-01

Supercritical fluid extraction was used to extract the alkaloid N-[7-(3′,4′-methylenedioxyphenyl)-2(Z),4(Z)-heptadienoyl]pyrrolidine from leaves of Piper amalago L. A three-level orthogonal array design matrix, OAD OA9(34), was used for optimization of the parameters of supercritical extraction of the alkaloid, employing supercritical carbon dioxide: extraction time (20, 40, and 60 min), temperature (40, 50, and 60°C), pressure (150, 200, and 250 bar), and the use of cosolvents (ethanol, methanol, and propyleneglycol). All parameters had significant effect on the alkaloid yield. The alkaloid yield after 60 min of extraction without cosolvents at 9 different conditions (32) in terms of temperature (40, 50, and 60°C) and pressure (150, 200, and 250 bar) was also evaluated. The optimal yield (≈3.8 mg g−1) was obtained with supercritical CO2 + methanol (5% v : v) at 40°C and 200 bar for 60 min of extraction. PMID:28539966

Influence of high-pressure homogenization, ultrasonication, and supercritical fluid on free astaxanthin extraction from β-glucanase-treated Phaffia rhodozyma cells.

PubMed

Hasan, Mojeer; Azhar, Mohd; Nangia, Hina; Bhatt, Prakash Chandra; Panda, Bibhu Prasad

2016-01-01

In this study astaxanthin production by Phaffia rhodozyma was enhanced by chemical mutation using ethyl methane sulfonate. The mutant produces a higher amount of astaxanthin than the wild yeast strain. In comparison to supercritical fluid technique, high-pressure homogenization is better for extracting astaxanthin from yeast cells. Ultrasonication of dimethyl sulfoxide, hexane, and acetone-treated cells yielded less astaxanthin than β-glucanase enzyme-treated cells. The combination of ultrasonication with β-glucanase enzyme is found to be the most efficient method of extraction among all the tested physical and chemical extraction methods. It gives a maximum yield of 435.71 ± 6.55 µg free astaxanthin per gram of yeast cell mass.

Preparative isolation and purification of hainanmurpanin, meranzin, and phebalosin from leaves of Murraya exotica L. using supercritical fluid extraction combined with consecutive high-speed countercurrent chromatography.

PubMed

Yan, Rongwei; Shen, Jie; Liu, Xiaojing; Zou, Yong; Xu, Xinjun

2018-05-01

The objective of this study was to develop a consecutive preparation method for the isolation and purification of hainanmurpanin, meranzin, and phebalosin from leaves of Murraya exotica L. The process involved supercritical fluid extraction with CO 2 , solvent extraction, and two-step high-speed countercurrent chromatography. Pressure, temperature, and the volume of entrainer were optimized as 27 MPa, 52°C, and 60 mL by response surface methodology in supercritical fluid extraction with CO 2 , and the yield of the crude extracts was 7.91 g from 100 g of leaves. Subsequently, 80% methanol/water was used to extract and condense the three compounds from the crude extracts, and 4.23 g of methanol/water extracts was obtained. Then, a two-step high-speed countercurrent chromatography procedure was developed for the isolation of the three target compounds from methanol/water extracts, including conventional high-speed countercurrent chromatography for further enrichment and consecutive high-speed countercurrent chromatography for purification. The yield of concentrates from high-speed countercurrent chromatography was 2.50 g from 4.23 g of methanol/water extracts. Finally, the consecutive high-speed countercurrent chromatography produced 103.2 mg of hainanmurpanin, 244.7 mg of meranzin, and 255.4 mg of phebalosin with purities up to 97.66, 99.36, and 98.64%, respectively, from 900 mg of high-speed countercurrent chromatography concentrates in one run of three consecutive sample loadings without exchanging a solvent system. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Extraction of nobiletin from Citrus Unshiu peels by supercritical fluid and its CRE-mediated transcriptional activity.

PubMed

Oba, Chisato; Ota, Masaki; Nomura, Koichiro; Fujiwara, Hironori; Takito, Jiro; Sato, Yoshiyuki; Ohizumi, Yasushi; Inomata, Hiroshi

2017-04-15

Polymethoxyflavone (PMF) is one of bioactive compounds in Citrus Unshiu and included mainly in the peels rather than the fruits, seeds and leaves. Supercritical CO 2 extraction is one candidate for selective extraction of polymethoxyflavone and in this study, supercritical CO 2 extraction with/without ethanol entrainer from Citrus Unshiu peels was examined at a temperature of 333K and a pressure of 30MPa. CRE (cyclic AMP response element)-mediated transcriptional assay was examined by using the extracts from supercritical fluid extraction. The results showed that extracts including nobiletin increased with increasing ethanol concentration in supercritical CO 2 and the elapsed extraction time. Extracts at ethanol concentration of 5 mol% showed high CRE-mediated transcription activity. This can be caused by activity of the extract including nobiletin in addition to the other methoxylated flavonoid species such as tangeretin. Extracts at ethanol concentration of 50% showed the highest CRE-mediated transcription activity, which can be attributed to flavonoid glycoside such as hesperidin. From our investigations, flavonoid glycoside can be one of promoters of CRE-mediated transcription activity. Copyright © 2017 Elsevier GmbH. All rights reserved.

Extracting metals directly from metal oxides

DOEpatents

Wai, Chien M.; Smart, Neil G.; Phelps, Cindy

1997-01-01

A method of extracting metals directly from metal oxides by exposing the oxide to a supercritical fluid solvent containing a chelating agent is described. Preferably, the metal is an actinide or a lanthanide. More preferably, the metal is uranium, thorium or plutonium. The chelating agent forms chelates that are soluble in the supercritical fluid, thereby allowing direct removal of the metal from the metal oxide. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is selected from the group consisting of .beta.-diketones, halogenated .beta.-diketones, phosphinic acids, halogenated phosphinic acids, carboxylic acids, halogenated carboxylic acids, and mixtures thereof. In especially preferred embodiments, at least one of the chelating agents is fluorinated. The method provides an environmentally benign process for removing metals from metal oxides without using acids or biologically harmful solvents. The chelate and supercritical fluid can be regenerated, and the metal recovered, to provide an economic, efficient process.

Extracting metals directly from metal oxides

DOEpatents

Wai, C.M.; Smart, N.G.; Phelps, C.

1997-02-25

A method of extracting metals directly from metal oxides by exposing the oxide to a supercritical fluid solvent containing a chelating agent is described. Preferably, the metal is an actinide or a lanthanide. More preferably, the metal is uranium, thorium or plutonium. The chelating agent forms chelates that are soluble in the supercritical fluid, thereby allowing direct removal of the metal from the metal oxide. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is selected from the group consisting of {beta}-diketones, halogenated {beta}-diketones, phosphinic acids, halogenated phosphinic acids, carboxylic acids, halogenated carboxylic acids, and mixtures thereof. In especially preferred embodiments, at least one of the chelating agents is fluorinated. The method provides an environmentally benign process for removing metals from metal oxides without using acids or biologically harmful solvents. The chelate and supercritical fluid can be regenerated, and the metal recovered, to provide an economic, efficient process. 4 figs.

A Novel CO2-Responsive Viscoelastic Amphiphilic Surfactant Fluid for Fracking in Enhanced Oil/Gas Recovery

NASA Astrophysics Data System (ADS)

Zhong, L.; Wu, X.; Dai, C.

2017-12-01

Over the past decade, the rapid rise of unconventional shale gas and tight sandstone oil development through horizontal drilling and high volume hydraulic fracturing has expanded the extraction of hydrocarbon resources. Hydraulic fracturing fluids play very important roles in enhanced oil/gas recovery. However, damage to the reservoir rock and environmental contamination caused by hydraulic fracturing flowback fluids has raised serious concerns. The development of reservoir rock friendly and environmental benign fracturing fluids is in immediate demand. Studies to improve properties of hydraulic fracturing fluids have found that viscoelastic surfactant (VES) fracturing fluid can increase the productivity of gas/oil and be efficiently extracted after fracturing. Compared to conventional polymer fracturing fluid, VES fracturing fluid has many advantages, such as few components, easy preparation, good proppant transport capacity, low damage to cracks and formations, and environment friendly. In this work, we are developing a novel CO2-responsive VES fracking fluid that can readily be reused. This fluid has a gelling-breaking process that can be easily controlled by the presence of CO2 and its pressure. We synthesized erucamidopropyl dimethylamine (EA) as a thickening agent for hydraulic fracturing fluid. The influence of temperature, presence of CO2 and pressure on the viscoelastic behavior of this fluid was then investigated through rheological measurements. The fracturing fluid performance and recycle property were lastly studied using core flooding tests. We expect this fluid finds applications not only in enhanced oil/gas recovery, but also in areas such as controlling groundwater pollution and microfluidics.

Bio-Oil Separation and Stabilization by Near-Critical Propane Fractionation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ginosar, Daniel M.; Petkovic, Lucia M.; Agblevor, Foster A.

Bio-oils produced by thermal process are promising sources of sustainable, low greenhouse gas alternative fuels. These thermal processes are also well suited to decentralized energy production due to low capital and operating costs. Algae feedstocks for bio-oil production are of particular interest, due in part to their high-energy growth yields. Further, algae can be grown in non-arable areas in fresh, brackish, salt water, or even waste water. Unfortunately, bio-oils produced by thermal processes present significant stability challenges. These oils have complex chemical compositions, are viscous, reactive, and thermally unstable. Further, the components within the oils are difficult to separate bymore » fractional distillation. By far, the most effective separation and stabilization method has been solvent extraction. However, liquid phase extraction processes pose two main obstacles to commercialization; they require a significant amount of energy to remove and recover the solvent from the product, and they have a propensity for the solvent to become contaminated with minerals from the char and ash present in the original bio-oil. Separation and fractionation of thermally produced bio-oils using supercritical fluids (SCF) offers the advantages of liquid solvent extraction while drastically reducing energy demands and the predisposition to carry over solids into the extracted phase. SCFs are dense fluids with liquid-like solvent properties and gas-like transport properties. Further, SCF density and solvent strength can be tuned with minor adjustments in pressure, co-solvent addition, or gas anti-solvent addition. Catalytic pyrolysis oils were produced from Scenedesmus dimorphus algae using a fluid catalytic cracking catalyst. Bio-oil produced from catalytic fast pyrolysis (CFP) was separated using critical fluids. Propane extraction was performed at 65 °C at a fluid reduced pressure of 2.0 (85 bar) using an eight to one solvent to feed ratio by weight. Extraction of catalytic fast pyrolysis oil with near critical propane produced an oil extract that was physically and chemically different from and more stable than the original oil. The propane extract displayed lower viscosity and lower average molecular weight. The species present in the propane extract were likely the less polar that would be expected from using a non-polar solvent (propane). Carbonyl containing species in the extract were likely ketones and esters. The raffinate contained a higher amnount of OH bonded species along with the more polar more polar acids, amides, and alcohols. The higher concentration of nitrogen in the raffinate may confirm the presence of amides. Viscosity of the propane extract increased only half as much as that of the CFP bio-oil. Further, In situ NMR aging studies showed that the propane extract was more stable than the raw oil. In conclusion, propane extraction is a promising method to decrease the nitrogen content of bio-oils and to improve the stability of bio-oils obtained by the catalytic pyrolysis of algae based biomass.« less

Developing an effective means to reduce 5-hydroxymethyl-2-furfural from caramel colour.

PubMed

Guan, Yongguang; Chen, Mingshun; Yu, Shujuan; Tang, Qiang; Yan, He

2014-01-15

Supercritical carbon dioxide fluid extraction was used to extract 5-hydroxymethyl-2-furfural from caramel colour (solid content was about 75%). The procedure was carried out by response surface methodology using a quadratic polynomial model. Extraction pressure, time, temperature and ethanol content were selected as the independent variables. Conditions to obtain the highest extraction ratio of 5-hydroxymethyl-2-furfural were determined to be an extraction pressure of 21.65MPa, time of 46.7min, temperature of 35°C and 70% ethanol content of caramel colour. The predicted 5-hydroxymethyl-2-furfural extraction ratio was 87.42%. Under the conditions stated above, the experimental value of 5-hydroxymethyl-2-furfural extraction ratio was 86.98%, which was similar to the predicted value by the model. This study indicated that supercritical carbon dioxide fluid extraction can effectively reduce 5-hydroxymethyl-2-furfural from caramel colour, which can help food industry to improve the safety of the food material, as well as provide more healthy caramel colour for human beings. Copyright © 2013 Elsevier Ltd. All rights reserved.

Social Foundations of Education as an Unwelcome Counter-Narrative and as Educational Praxis

ERIC Educational Resources Information Center

Tozer, Steve

2018-01-01

I am grateful for this opportunity to reflect on the field of Social Foundations of Education (SFE), in part because it affords an opportunity to advance an historical analysis of the trajectory of the field different from what we provided when my colleagues and I sent to press the "Handbook of Research the Social Foundations of…

Economic Analysis of National Nuclear Security Administration (NNSA) Modernization Alternatives

DTIC Science & Technology

2007-11-01

without nuclear testing; works to reduce global danger from weapons of mass destruction; provides the U.S. Navy with safe and effective nuclear...SFE) covers the acquisition of glove boxes, long-lead facility, and actinide chemistry/materials characterization (AC/MC) equipment whose uniqueness...Hazard Category II AC/MC and actinide Research and Development operations, special nuclear 5 Babcock

Regional Frequency Computation Users Manual.

DTIC Science & Technology

1972-07-01

increment of flow used to prevent infinite logarithms for events with zero flow X = Mean logarithm of flow events N = Total years of record S = Unbiased...C LIBRARY 3’jr.RfUTINFES USEO--ALflGpSINvAB3 1002 c PRGRAM ~ SUBRflUTINES CR0UTpR,chfNN-SFE COt’MENTS I-N RNGEN 100 C REFERENCE TOl TAPE ? AT

Integrating Space Systems Operations at the Marine Expeditionary Force Level

DTIC Science & Technology

2015-06-01

Electromagnetic Interference ENVI Environment for Visualizing Images EW Electronic Warfare xvi FA40 Space Operations Officer FEC Fires and Effects...Information Facility SFE Space Force Enhancement SIGINT Signals Intelligence SSA Space Situational Awareness SSE Space Support Element STK Systems...April 23, 2015. 65 • GPS Interference and Navigation Tool (GIANT) for providing GPS accuracy prediction reports • Systems Toolkit ( STK ) Analysis

An Empirical Study: To What Extent and in What Ways Does Social Foundations of Education Inform Four Teachers' Educational Beliefs and Classroom Practices?

ERIC Educational Resources Information Center

Benchik-Osborne, Jacquelyn R.

2013-01-01

Within the state selected for this study, teacher preparation programs and state certification criterion require that educators examine the relationship between school and society within social foundations of education (SFE) coursework. Using observations and interviews, this study examines to what extent four experienced, urban classroom teachers…

Correlation between substratum roughness and wettability, cell adhesion, and cell migration.

PubMed

Lampin, M; Warocquier-Clérout; Legris, C; Degrange, M; Sigot-Luizard, M F

1997-07-01

Cell adhesion and spreading of chick embryo vascular and corneal explants grown on rough and smooth poly (methyl methacrylate) (PMMA) were analyzed to test the cell response specificity to substratum surface properties. Different degrees of roughness were obtained by sand-blasting PMMA with alumina grains. Hydrophilic and hydrophobic components of the surface free energy (SFE) were calculated according to Good-van Oss's model. Contact angles were determined using a computerized angle meter. The apolar component of the SFE gamma s(LW), increased with a slight roughness whereas the basic component, gamma s-, decreased. The acido-basic properties disappeared as roughness increased. Incubation of PMMA in culture medium, performed to test the influence if the biological environment, allowed surface adsorption of medium proteins which annihilated roughness effect and restored hydrophilic properties. An organotypic culture assay was carried out in an attempt to relate the biocompatibility to substratum surface state. Cell migration was calculated from the area of cell layer. Cellular adhesion was determined by measuring the kinetic of release of enzymatically dissociated cells. A slight roughness raised the migration are to an upper extent no matter which cell type. Enhancement of the cell adhesion potential was related to the degree of roughness and the hydrophobicity.

Influence of stacking fault energy on defect structures and microhardness of Cu and Cu alloys.

PubMed

Tao, Jing-Mei; Li, Dai; Li, Cai-Ju; Zhu, Xin-Kun

2011-12-01

Nano-structured Cu, Cu-10 wt%Zn and Cu-2 wt%Al with stacking fault energies (SFE) of 78, 35 and 37 mJ/m2, respectively, were preprared through high energy ball milling. X-ray diffraction and Vickers microharness test were used to investigate the microstructure and microhardness of all the samples after ball milling. X-ray diffraction measurements indicate that lower SFEs lead both to decrease in grain size and increase in microstrain, dislocation and twin densities for Cu-10 wt%Zn and Cu-2 wt%Al after 5 h of ball milling. The microhardnesses of Cu-10 wt%Zn and Cu-2 wt%Al reach to nearly the same values of 2.5 GPa after 5 h of ball milling, which is higher than that of Cu of 2.0 GPa. Two factors are considered to contribute to the finer grian size and higher microhardness of Cu-10 wt%Zn and Cu-2 wt%Al: (1) the effect of solid solution strengthening, which result in the interaction of solute atoms with screw dislocations; (2) the introduction of deformation twins during ball milling process by the decreasing of SFE, which results in the grain refinement.

DETECTION OF PHOSPHORUS, SULPHUR, AND ZINC IN THE CARBON-ENHANCED METAL-POOR STAR BD+44 493

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roederer, Ian U.; Placco, Vinicius M.; Beers, Timothy C., E-mail: iur@umich.edu

2016-06-20

The carbon-enhanced metal-poor star BD+44°493 ([Fe/H] = −3.9) has been proposed as a candidate second-generation star enriched by metals from a single Pop III star. We report the first detections of P and S and the second detection of Zn in any extremely metal-poor carbon-enhanced star, using new spectra of BD+44°493 collected by the Cosmic Origins Spectrograph on the Hubble Space Telescope . We derive [P/Fe] = −0.34 ± 0.21, [S/Fe] = +0.07 ± 0.41, and [Zn/Fe] = −0.10 ± 0.24. We increase by 10-fold the number of Si i lines detected in BD+44°493, yielding [Si/Fe] = +0.15 ± 0.22.more » The [S/Fe] and [Zn/Fe] ratios exclude the hypothesis that the abundance pattern in BD+44°493 results from depletion of refractory elements onto dust grains. Comparison with zero-metallicity supernova (SN) models suggests that the stellar progenitor that enriched BD+44°493 was massive and ejected much less than 0.07 M {sub ⊙} of {sup 56}Ni, characteristic of a faint SN.« less

Hydrophilic property of 316L stainless steel after treatment by atmospheric pressure corona streamer plasma using surface-sensitive analyses

NASA Astrophysics Data System (ADS)

Al-Hamarneh, Ibrahim; Pedrow, Patrick; Eskhan, Asma; Abu-Lail, Nehal

2012-10-01

Surgical-grade 316L stainless steel (SS 316L) had its surface hydrophilic property enhanced by processing in a corona streamer plasma reactor using O2 gas mixed with Ar at atmospheric pressure. Reactor excitation was 60 Hz ac high-voltage (0-10 kVRMS) applied to a multi-needle-to-grounded screen electrode configuration. The treated surface was characterized with a contact angle tester. Surface free energy (SFE) for the treated stainless steel increased measurably compared to the untreated surface. The Ar-O2 plasma was more effective in enhancing the SFE than Ar-only plasma. Optimum conditions for the plasma treatment system used in this study were obtained. X-ray photoelectron spectroscopy (XPS) characterization of the chemical composition of the treated surfaces confirms the existence of new oxygen-containing functional groups contributing to the change in the hydrophilic nature of the surface. These new functional groups were generated by surface reactions caused by reactive oxidation of substrate species. Atomic force microscopy (AFM) images were generated to investigate morphological and roughness changes on the plasma treated surfaces. The aging effect in air after treatment was also studied.

Supercritical fluid extraction of the non-polar organic compounds in meteorites

NASA Astrophysics Data System (ADS)

Sephton, M. A.; Pillinger, C. T.; Gilmour, I.

2001-01-01

The carbonaceous chondrite meteorites contain a variety of extraterrestrial organic molecules. These organic components provide a valuable insight into the formation and evolution of the solar system. Attempts at obtaining and interpreting this information source are hampered by the small sample sizes available for study and the interferences from terrestrial contamination. Supercritical fluid extraction represents an efficient and contamination-free means of isolating extraterrestrial molecules. Gas chromatography-mass spectrometry analyses of extracts from Orgueil and Cold Bokkeveld reveal a complex mixture of free non-polar organic molecules which include normal alkanes, isoprenoid alkanes, tetrahydronaphthalenes and aromatic hydrocarbons. These organic assemblages imply contributions from both terrestrial and extraterrestrial sources.

Extraction of three-dimensional silver nanostructures with supercritical fluid

NASA Astrophysics Data System (ADS)

Taguchi, Natsuo; Takeyasu, Nobuyuki; Kawata, Satoshi

2018-02-01

In a previous report, a self-growing approach was proposed for fabricating complex silver nanostructures, where silver dendrites were grown at silver nanoseeds in silver ion solution owing to plasmonic heating with ultraviolet light. Structures were deformed or destroyed when they were extracted with acetone and dried in air. In this Letter, we discuss the use of supercritical carbon dioxide fluid for the nondestructive extraction of nanostructures. We show the experimental results and discuss the laser power dependence of resultant structures. Another experiment was performed for nanostructure growth inside an agarose gel as a matrix. Silver nanostructures were immobilized without damage in an agarose skeleton network.

SUPERCRITICAL FLUID EXTRACTION OF SEMI-VOLATILE ORGANIC COMPOUNDS FROM PARTICLES

EPA Science Inventory

A nitrogen oxide flux chamber was modified to measure the flux of semi-volatile organic compounds (SVOCs). Part of the modification involved the development of methods to extract SVOCs from polyurethane foam (PUF), sand, and soil. Breakthroughs and extraction efficiencies were ...

The Measurement of Human Body-Fluid Volumes: Resting Fluid Volumes Before and After Heat Acclimation

DTIC Science & Technology

2001-01-01

equilibration period. Erythrocytes aliquots were haemolysed before counting with saponin . Both counts were used to correct the derived ECFV, which was...was largely in accordance with the procedures of Greenleaf et al. (1980). This technique used an extraction procedure in which the dye was first...collection. Therefore, the above extraction procedure was not used. A major limitation of using a cellulose column is the possibility of not collecting all

Environmental risks associated with unconventional gas extraction: an Australian perspective

NASA Astrophysics Data System (ADS)

Mallants, Dirk; Bekele, Elise; Schmidt, Wolfgang; Miotlinski, Konrad; Gerke Gerke, Kirill

2015-04-01

Coal seam gas is naturally occurring methane gas (CH4) formed by the degradation of organic material in coal seam layers over geological times, typically over several millions of years. Unlike conventional gas resources, which occur as discrete accumulations in traps formed by folds and other structures in sedimentary layers, coal seam gas is generally trapped in low permeable rock by adsorption of the gas molecules within the rock formation and cannot migrate to a trap and form a conventional gas deposit. Extraction of coal seam gas requires producers to de pressurise the coal measures by abstracting large amounts of groundwater through pumping. For coal measures that have too low permeabilities for gas extraction to be economical, mechanical and chemical techniques are required to increase permeability and thus gas yield. One such technique is hydraulic fracturing (HF). Hydraulic fracturing increases the rate and total amount of gas extracted from coal seam gas reservoirs. The process of hydraulic fracturing involves injecting large volumes of hydraulic fracturing fluids under high pressure into the coal seam layers to open up (i.e. fracture) the gas-containing coal layers, thus facilitating extraction of methane gas through pumping. After a hydraulic fracturing operation has been completed in a coal seam gas well, the fracturing fluid pressure is lowered and a significant proportion of the injected fluid returns to the surface as "flowback" water via coal seam gas wells. Flowback water is fluid that returns to the surface after hydraulic fracturing has occurred but before the well is put into production; whereas produced water is fluid from the coal measure that is pumped to the surface after the well is in production. This paper summarises available literature data from Australian coal seam gas practices on i) spills from hydraulic fracturing-related fluids used during coal seam gas drilling and hydraulic fracturing operations, ii) leaks to soil and shallow groundwater of flowback water and produced water from surface impoundments, iii) risks from well integrity failure, and iv) increased gas in water bores.

Evaluation of DNA extraction methods and their clinical application for direct detection of causative bacteria in continuous ambulatory peritoneal dialysis culture fluids from patients with peritonitis by using broad-range PCR.

PubMed

Kim, Si Hyun; Jeong, Haeng Soon; Kim, Yeong Hoon; Song, Sae Am; Lee, Ja Young; Oh, Seung Hwan; Kim, Hye Ran; Lee, Jeong Nyeo; Kho, Weon-Gyu; Shin, Jeong Hwan

2012-03-01

The aims of this study were to compare several DNA extraction methods and 16S rDNA primers and to evaluate the clinical utility of broad-range PCR in continuous ambulatory peritoneal dialysis (CAPD) culture fluids. Six type strains were used as model organisms in dilutions from 10(8) to 10(0) colony-forming units (CFU)/mL for the evaluation of 5 DNA extraction methods and 5 PCR primer pairs. Broad-range PCR was applied to 100 CAPD culture fluids, and the results were compared with conventional culture results. There were some differences between the various DNA extraction methods and primer sets with regard to the detection limits. The InstaGene Matrix (Bio-Rad Laboratories, USA) and Exgene Clinic SV kits (GeneAll Biotechnology Co. Ltd, Korea) seem to have higher sensitivities than the others. The results of broad-range PCR were concordant with the results from culture in 97% of all cases (97/100). Two culture-positive cases that were broad-range PCR-negative were identified as Candida albicans, and 1 PCR-positive but culture-negative sample was identified as Bacillus circulans by sequencing. Two samples among 54 broad-range PCR-positive products could not be sequenced. There were differences in the analytical sensitivity of various DNA extraction methods and primers for broad-range PCR. The broad-range PCR assay can be used to detect bacterial pathogens in CAPD culture fluid as a supplement to culture methods.

Growth rate of a penny-shaped crack in hydraulic fracturing of rocks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abe, H.; Keer, L.M.; Mura, T.

1976-01-01

The deformation and growth of a crack, fractured hydraulically, is investigated when fluid is injected from an inlet into the crack at a constant flow rate. The total flow rate at the inlet is divided as follows: flow rate extracted from an outlet hole; fluid loss rate from the crack surface; and total fluid mass change in the crack. Two cases are considered: (1) inlet flow rate is initially greater than the sum of the outlet flow and fluid loss rates; and (2) the reverse holds true. Ranges are shown for which the crack attains stationary states for given inletmore » flow rate and outlet pressure. For these two cases reasonable outlet flow rates are obtained when the outlet pressure is less than or equal to the difference between the tectonic stress and the fluid head at the inlet. Results are expected to be of use in considerations of heat extraction from hot, dry rock.« less

A competitive enzyme-linked immunosorbent assay for quantification of tetrastatin in body fluids and tumor extracts.

PubMed

Dupont-Deshorgue, A; Oudart, J B; Brassart, B; Deslee, G; Perotin, J M; Diebold, M D; Monboisse, J C; Ramont, L; Brassart-Pasco, S

2015-08-01

Basement membrane collagens or derived fragments are measured in biological fluids such as blood and urine of patients and appear to be useful for diagnosis, prognostication, or treatment monitoring as proposed for endostatin, a fragment of collagen XVIII, or tumstatin, a fragment of collagen IV. Tetrastatin, the NC1 alpha 4 collagen IV domain, was previously reported to inhibit tumor growth and angiogenesis. The aim of this study was to develop and validate a method to measure tetrastatin concentrations in human fluids. We developed a competitive enzyme-linked immunosorbent assay (ELISA). It allowed measuring tetrastatin levels in human serum, bronchial aspiration and bronchoalveolar lavage fluids, and lung tissue extracts. The tetrastatin level was significantly higher in tumor tissues than in healthy lung tissues. Tetrastatin competitive ELISA could be useful to quantify tetrastatin in tissues and biological fluids for the diagnosis or prognostication of diseases in which basement membrane metabolism may be altered, especially tumor progression. Copyright © 2015 Elsevier Inc. All rights reserved.

Soil properties affecting wheat yields following drilling-fluid application.

PubMed

Bauder, T A; Barbarick, K A; Ippolito, J A; Shanahan, J F; Ayers, P D

2005-01-01

Oil and gas drilling operations use drilling fluids (mud) to lubricate the drill bit and stem, transport formation cuttings to the surface, and seal off porous geologic formations. Following completion of the well, waste drilling fluid is often applied to cropland. We studied potential changes in soil compaction as indicated by cone penetration resistance, pH, electrical conductivity (EC(e)), sodium adsorption ratio (SAR), extractable soil and total straw and grain trace metal and nutrient concentrations, and winter wheat (Triticum aestivum L. 'TAM 107') grain yield following water-based, bentonitic drilling-fluid application (0-94 Mg ha(-1)) to field test plots. Three methods of application (normal, splash-plate, and spreader-bar) were used to study compaction effects. We measured increasing SAR, EC(e), and pH with drilling-fluid rates, but not to levels detrimental to crop production. Field measurements revealed significantly higher compaction within areas affected by truck travel, but also not enough to affect crop yield. In three of four site years, neither drilling-fluid rate nor application method affected grain yield. Extractions representing plant availability and plant analyses results indicated that drilling fluid did not significantly increase most trace elements or nutrient concentrations. These results support land application of water-based bentonitic drilling fluids as an acceptable practice on well-drained soils using controlled rates.

Droplet-Based Segregation and Extraction of Concentrated Samples

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buie, C R; Buckley, P; Hamilton, J

2007-02-23

Microfluidic analysis often requires sample concentration and separation techniques to isolate and detect analytes of interest. Complex or scarce samples may also require an orthogonal separation and detection method or off-chip analysis to confirm results. To perform these additional steps, the concentrated sample plug must be extracted from the primary microfluidic channel with minimal sample loss and dilution. We investigated two extraction techniques; injection of immiscible fluid droplets into the sample stream (''capping'''') and injection of the sample into an immiscible fluid stream (''extraction''). From our results we conclude that capping is the more effective partitioning technique. Furthermore, this functionalitymore » enables additional off-chip post-processing procedures such as DNA/RNA microarray analysis, realtime polymerase chain reaction (RT-PCR), and culture growth to validate chip performance.« less

Research activities on supercritical fluid science in food biotechnology.

PubMed

Khosravi-Darani, Kianoush

2010-06-01

This article serves as an overview, introducing the currently popular area of supercritical fluids and their uses in food biotechnology. Within each application, and wherever possible, the basic principles of the technique, as well as a description of the history, instrumentation, methodology, uses, problems encountered, and advantages over the traditional, non-supercritical methods are given. Most current commercial application of the supercritical extraction involve biologically-produced materials; the technique may be particularly relevant to the extraction of biological compounds in cases where there is a requirement for low-temperature processing, high mass-transfer rates, and negligible carrying over of the solvent into the final product. Special applications to food processing include the decaffeination of green coffee beans, the production of hops extracts, the recovery of aromas and flavors from herbs and spices, the extraction and fractionation of edible oils, and the removal of contaminants, among others. New advances, in which the extraction is combined with reaction or crystallization steps, may further increase the attractiveness of supercritical fluids in the bioprocess industries. To develop and establish a novel and effective alternative to heating treatment, the lethal action of high hydrostatic pressure CO(2) on microorganisms, with none or only a minimal heating process, has recently received a great deal of attention.

Effects of supercritical fluid extraction pressure on chemical composition, microbial population, polar lipid profile, and microstructure of goat cheese.

PubMed

Sánchez-Macías, D; Laubscher, A; Castro, N; Argüello, A; Jiménez-Flores, R

2013-03-01

The consumer trend for healthier food choices and preferences for low-fat products has increased the interest in low-fat cheese and nutraceutical dairy products. However, consumer preference is still for delicious food. Low- and reduced-fat cheeses are not completely accepted because of their unappealing properties compared with full-fat cheeses. The method reported here provides another option to the conventional cheese-making process to obtain lower fat cheese. Using CO(2) as a supercritical fluid offers an alternative to reduce fat in cheese after ripening, while maintaining the initial characteristics and flavor. The aim of this experiment was to evaluate the effect of pressure (10, 20, 30, and 40 × 10(6) Pa) of supercritical CO(2) on the amount of fat extracted, microbial population, polar lipid profile, and microstructure of 2 varieties of goat cheese: Majorero, a protected denomination of origin cheese from Spain, and goat Gouda-type cheese. The amount of fat was reduced 50 to 57% and 48 to 55% for Majorero and goat Gouda-type cheeses, respectively. Higher contents (on a fat basis) of sphingomyelin and phosphatidylcholine were found in Majorero cheese compared with control and goat Gouda-type cheeses. The microbial population was reduced after supercritical fluid extraction in both cheeses, and the lethality was higher as pressure increased in Majorero cheese, most noticeably on lactococcus and lactobacillus bacteria. The Gouda-type cheese did not contain any lactobacilli. Micrographs obtained from confocal laser scanning microscopy showed a more open matrix and whey pockets in the Majorero control cheese. This could explain the ease of extracting fat and reducing the microbial counts in this cheese after treatment with supercritical CO(2). Supercritical fluid extraction with CO(2) has great potential in the dairy industry and in commercial applications. The Majorero cheese obtained after the supercritical fluid extraction treatment was an excellent candidate as a low-fat goat cheese, lower in triglycerides and cholesterol but still with all the health benefits inherent in goat milk. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Rheoscopic Fluids in a Post-Kalliroscope World

NASA Astrophysics Data System (ADS)

Borrero-Echeverry, Daniel; Crowley, Christopher J.

2016-11-01

In rheoscopic flow visualization the working fluid is seeded with small plate-shaped particles, which preferentially align in the flow due to their anisotropy. This leads to preferential light scattering, which highlights qualitatively different regions of the flow. For the past four decades, the gold standard in rheoscopic flow visualization has been Kalliroscope, a commercial product consisting of crystalline guanine particles. Guanine is a shiny compound extracted from fish scales and has traditionally been used in cosmetics to provide a pearlescent effect. It stands out among other options for rheoscopic flow visualization (e.g., aluminum flakes or coated mica particles) due to its relatively good density match with water. Guanine extraction, however, is an expensive process and as the cosmetics industry has adopted less expensive alternatives, commercial guanine production has dropped, leading to the closure of the Kalliroscope Corporation in 2014. In this talk, we discuss our recent discovery of a rheoscopic fluid based on stearic acid crystals, which has an overall performance similar to, and in some cases superior to, Kalliroscope. This rheoscopic fluid can be extracted from household items making it very inexpensive and readily accessible to researchers around the world.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goven, A.J.; Chen, S.C.; Fitzpatrick, L.C.

Lysozyme activity in earthworm (Lumbricus terrestris) coelomic fluid and coelomocytes appears sufficiently sensitive for use as a nonmammalian biomarker to detect toxic effects of sublethal body burdens of Cu[sup 2+]. Lysozyme, a phylogenetically conserved enzyme, is capable of bactericidal activity via action on peptidoglycan of gram-positive bacterial cell walls and functions as a component of an organism's innate antimicrobial defense mechanism. Coelomic fluid and coelomocyte lysozyme activities, which exhibit temperature-response patterns similar to those of human saliva, plasma, serum and leukocyte extracts, were sensitive to Cu[sup 2+] exposure. Lysozyme activity of coelomic fluid and coelomocyte extracts from earthworms exposed formore » 5 d to CuSO[sub 4], using filter paper contact exposure, decreased with increasing sublethal Cu[sup 2+] concentrations of 0.05 and 0.1 [mu]g/cm[sup 2]. Compared to controls, coelomic fluid lysozyme activity was suppressed significantly at both exposure concentrations, whereas coelomocyte extract lysozyme activity was suppressed significantly at the 0.1-[mu]g/cm[sup 2] exposure concentration. Low inherent natural variability and sensitivity to sublethal Cu[sup 2+] body burdens indicate that lysozyme activity has potential as a biomarker for assaying immunotoxicity of metals.« less

Supercritical fluid technology: concepts and pharmaceutical applications.

PubMed

Deshpande, Praful Balavant; Kumar, G Aravind; Kumar, Averineni Ranjith; Shavi, Gopal Venkatesh; Karthik, Arumugam; Reddy, Meka Sreenivasa; Udupa, Nayanabhirama

2011-01-01

In light of environmental apprehension, supercritical fluid technology (SFT) exhibits excellent opportunities to accomplish key objectives in the drug delivery sector. Supercritical fluid extraction using carbon dioxide (CO(2)) has been recognized as a green technology. It is a clean and versatile solvent with gas-like diffusivity and liquid-like density in the supercritical phase, which has provided an excellent alternative to the use of chemical solvents. The present commentary provides an overview of different techniques using supercritical fluids and their future opportunity for the drug delivery industry. Some of the emerging applications of SFT in pharmaceuticals, such as particle design, drug solubilization, inclusion complex, polymer impregnation, polymorphism, drug extraction process, and analysis, are also covered in this review. The data collection methods are based on the recent literature related to drug delivery systems using SFT platforms. SFT has become a much more versatile and environmentally attractive technology that can handle a variety of complicated problems in pharmaceuticals. This cutting-edge technology is growing predominantly to surrogate conventional unit operations in relevance to the pharmaceutical production process. Supercritical fluid technology has recently drawn attention in the field of pharmaceuticals. It is a distinct conception that utilizes the solvent properties of supercritical fluids above their critical temperature and pressure, where they exhibit both liquid-like and gas-like properties, which can enable many pharmaceutical applications. For example, the liquid-like properties provide benefits in extraction processes of organic solvents or impurities, drug solubilization, and polymer plasticization, and the gas-like features facilitate mass transfer processes. It has become a much more versatile and environmentally attractive technology that can handle a variety of complicated problems in pharmaceuticals. This review is focused on different techniques that use supercritical fluids and their opportunities for the pharmaceutical sector.

Methylxanthines: properties and determination in various objects

NASA Astrophysics Data System (ADS)

Andreeva, Elena Yu; Dmitrienko, Stanislava G.; Zolotov, Yurii A.

2012-05-01

Published data on the properties and determination of caffeine, theophylline, theobromine and some other methylxanthines in various objects are surveyed and described systematically. Different sample preparation procedures such as liquid extraction from solid matrices and liquid-liquid, supercritical fluid and solid-phase extraction are compared. The key methods of analysis including chromatography, electrophoresis, spectrometry and electrochemical methods are discussed. Examples of methylxanthine determination in plants, food products, energy beverages, pharmaceuticals, biological fluids and natural and waste waters are given. The bibliography includes 393 references.

Segmentation of Unstructured Datasets

NASA Technical Reports Server (NTRS)

Bhat, Smitha

1996-01-01

Datasets generated by computer simulations and experiments in Computational Fluid Dynamics tend to be extremely large and complex. It is difficult to visualize these datasets using standard techniques like Volume Rendering and Ray Casting. Object Segmentation provides a technique to extract and quantify regions of interest within these massive datasets. This thesis explores basic algorithms to extract coherent amorphous regions from two-dimensional and three-dimensional scalar unstructured grids. The techniques are applied to datasets from Computational Fluid Dynamics and from Finite Element Analysis.

40 CFR Appendix 8 to Subpart A of... - Reference C16-C18 Internal Olefin Drilling Fluid Formulation

Code of Federal Regulations, 2014 CFR

2014-07-01

... Drilling Fluid Formulation 8 Appendix 8 to Subpart A of Part 435 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) OIL AND GAS EXTRACTION POINT...—Reference C16-C18 Internal Olefin Drilling Fluid Formulation The reference C16-C18 internal olefin drilling...

40 CFR Appendix 8 to Subpart A of... - Reference C16-C18 Internal Olefin Drilling Fluid Formulation

Code of Federal Regulations, 2012 CFR

2012-07-01

... Drilling Fluid Formulation 8 Appendix 8 to Subpart A of Part 435 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) OIL AND GAS EXTRACTION POINT...—Reference C16-C18 Internal Olefin Drilling Fluid Formulation The reference C16-C18 internal olefin drilling...

40 CFR Appendix 8 to Subpart A of... - Reference C16-C18 Internal Olefin Drilling Fluid Formulation

Code of Federal Regulations, 2013 CFR

2013-07-01

... Drilling Fluid Formulation 8 Appendix 8 to Subpart A of Part 435 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) OIL AND GAS EXTRACTION POINT...—Reference C16-C18 Internal Olefin Drilling Fluid Formulation The reference C16-C18 internal olefin drilling...

Using Neutrons to Study Fluid-Rock Interactions in Shales

NASA Astrophysics Data System (ADS)

DiStefano, V. H.; McFarlane, J.; Anovitz, L. M.; Gordon, A.; Hale, R. E.; Hunt, R. D.; Lewis, S. A., Sr.; Littrell, K. C.; Stack, A. G.; Chipera, S.; Perfect, E.; Bilheux, H.; Kolbus, L. M.; Bingham, P. R.

2015-12-01

Recovery of hydrocarbons by hydraulic fracturing depends on complex fluid-rock interactions that we are beginning to understand using neutron imaging and scattering techniques. Organic matter is often thought to comprise the majority of porosity in a shale. In this study, correlations between the type of organic matter embedded in a shale and porosity were investigated experimentally. Selected shale cores from the Eagle Ford and Marcellus formations were subjected to pyrolysis-gas chromatography, Differential Thermal Analysis/Thermogravimetric analysis, and organic solvent extraction with the resulting affluent analyzed by gas chromatography-mass spectrometry. The pore size distribution of the microporosity (~1 nm to 2 µm) in the Eagle Ford shales was measured before and after solvent extraction using small angle neutron scattering. Organics representing mass fractions of between 0.1 to 1 wt.% were removed from the shales and porosity generally increased across the examined microporosity range, particularly at larger pore sizes, approximately 50 nm to 2 μm. This range reflects extraction of accessible organic material, including remaining gas molecules, bitumen, and kerogen derivatives, indicating where the larger amount of organic matter in shale is stored. An increase in porosity at smaller pore sizes, ~1-3 nm, was also present and could be indicative of extraction of organic material stored in the inter-particle spaces of clays. Additionally, a decrease in porosity after extraction for a sample was attributed to swelling of pores with solvent uptake. This occurred in a shale with high clay content and low thermal maturity. The extracted hydrocarbons were primarily paraffinic, although some breakdown of larger aromatic compounds was observed in toluene extractions. The amount of hydrocarbon extracted and an overall increase in porosity appeared to be primarily correlated with the clay percentage in the shale. This study complements fluid transport neutron imaging studies, to explain the physics and chemistry of fluid-rock behavior. Research supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division and the Bredesen Center at the University of Tennessee.

A fully automated liquid–liquid extraction system utilizing interface detection

PubMed Central

Maslana, Eugene; Schmitt, Robert; Pan, Jeffrey

2000-01-01

The development of the Abbott Liquid-Liquid Extraction Station was a result of the need for an automated system to perform aqueous extraction on large sets of newly synthesized organic compounds used for drug discovery. The system utilizes a cylindrical laboratory robot to shuttle sample vials between two loading racks, two identical extraction stations, and a centrifuge. Extraction is performed by detecting the phase interface (by difference in refractive index) of the moving column of fluid drawn from the bottom of each vial containing a biphasic mixture. The integration of interface detection with fluid extraction maximizes sample throughput. Abbott-developed electronics process the detector signals. Sample mixing is performed by high-speed solvent injection. Centrifuging of the samples reduces interface emulsions. Operating software permits the user to program wash protocols with any one of six solvents per wash cycle with as many cycle repeats as necessary. Station capacity is eighty, 15 ml vials. This system has proven successful with a broad spectrum of both ethyl acetate and methylene chloride based chemistries. The development and characterization of this automated extraction system will be presented. PMID:18924693

Recovery of biomolecules from food wastes--a review.

PubMed

Baiano, Antonietta

2014-09-17

Food wastes are produced by a variety of sources, ranging from agricultural operations to household consumption. About 38% occurs during food processing. At present, the European Union legislation encourages the exploitation of co-products. This valorisation can be achieved through the extraction of high-value components such as proteins, polysaccharides, fibres, flavour compounds, and phytochemicals, which can be re-used as nutritionally and pharmacologically functional ingredients. Extraction can proceed according to solid-liquid extraction, Soxhlet extraction, pressurized fluid extraction, supercritical fluid extraction, ultrasound-assisted extraction, microwave-assisted extraction, pulsed electric field extraction, and enzyme-assisted extraction. Nevertheless, these techniques cannot be used indiscriminately and their choice depends on the type of biomolecules and matrix, the scale processing (laboratory or industrial), the ratio between production costs and economic values of the compounds to be extracted. The vegetable wastes include trimmings, peelings, stems, seeds, shells, bran, residues remaining after extraction of oil, starch, sugar, and juice. The animal-derived wastes include wastes from bred animals, wastes from seafood, wastes from dairy processing. The recovered biomolecules and by-products can be used to produce functional foods or as adjuvants in food processing or in medicinal and pharmaceutical preparations. This work is an overview of the type and amounts of food wastes; food waste legislation; conventional and novel techniques suitable for extracting biomolecules; food, medicinal and pharmaceutical uses of the recovered biomolecules and by-products, and future trends in these areas.

The importance of geochemical processes for the sustainability of deep geothermal systems: insights from coupled thermal-hydraulic-chemical modeling of the geothermal system at Bad Blumau, Austria

NASA Astrophysics Data System (ADS)

Alt-Epping, P.; Waber, H. N.; Eichinger, L.; Diamond, L. W.

2009-04-01

We use reactive-transport models patterned after the geothermal system at Bad Blumau, Austria, to track the fate of a fluid during its ascent from the geothermal reservoir to the surface, where it undergoes heat- and CO2-extraction, and during its subsequent reinjection into the deep aquifer. The fluid in the reservoir is in equilibrium with the carbonate-dominated mineralogy of the aquifer rock at local temperature and pressure conditions. Pressure and conductive temperature changes during ascent and descent of the fluid induce changes in mineral solubilities. Subsequent mineral precipitation within the borehole changes the fluid composition and gradually clogs the borehole, thereby obstructing fluid flow. Because different minerals exhibit different solubilities as a function of temperature, the mineral assemblages that precipitate in the production well are distinct from those in the injection well. For instance, if the fluid in the reservoir is saturated in quartz, then the prograde solubility behaviour of quartz favours its precipitation in the production well. Conversely, carbonate minerals tend to precipitate in the injection well owing to their retrograde solubility functions. However, calculating the distribution of mineral phases is complicated by the fact that the precipitation of some minerals is kinetically controlled, such that they may continue to precipitate far into the injection well (e.g. quartz). The strongest modification of the fluid composition and the greatest potential for mineral precipitation occurs during heat extraction, and, in the particular case of Bad Blumau, during the extraction of CO2 at the surface. The extraction of CO2 entails a dramatic increase in the pH and leads to massive precipitation of carbonate minerals. Simulations suggest that, in the worst case, the extraction of CO2 can cause the borehole to be sealed by carbonate minerals within a few weeks. Thus, the use of chemical additives to inhibit carbonate precipitation is imperative in the Bad Blumau system. Furthermore, any modification of the fluid composition caused by mineral precipitation along the fluid's pathway means that the reinjected fluid is no longer in equilibrium with the aquifer rock. Consequently, rock-water interaction and fluid mixing at the base of the injection well drive chemical reactions that cause changes in porosity and permeability of the aquifer, potentially compromising the efficiency of the geothermal system. One concern during geothermal energy production is that of chemical corrosion of the borehole casing. For a range of "what-if" scenarios we explore the effect of corrosion on the fluid composition and on mineral precipitation to identify chemical fingerprints that could be used as corrosion indicators. Once suitable indicators are identified, incipient corrosion could be detected early on during regular chemical monitoring. Corrosion of the casing is typically associated with the release of Fe and H2 into the circulating fluid. However, the implications of this release depend on the local chemical conditions where corrosion occurs. For instance, elevated H2 in the fluid is a corrosion indicator only if it is not involved in subsequent redox reactions. Similarly, low H2 concentrations do not rule out possible corrosion. In general, the interpretation of a fluid or a mineral sample requires the understanding of chemical processes that occur along the flowpath throughout the geothermal system. If direct observations are not possible, then this understanding can only be achieved through numerical simulations that integrate and couple fluid flow, heat transport and chemical reactions within one theoretical framework. Our simulations demonstrate that these models are useful for quantifying the impact and minimizing the risk that chemical reactions may have on the productivity and sustainability of a geothermal system.

Links between fluid circulation, temperature, and metamorphism in subducting slabs

USGS Publications Warehouse

Spinelli, G.A.; Wang, K.

2009-01-01

The location and timing of metamorphic reactions in subducting lithosph??re are influenced by thermal effects of fluid circulation in the ocean crust aquifer. Fluid circulation in subducting crust extracts heat from the Nankai subduction zone, causing the crust to pass through cooler metamorphic faci??s than if no fluid circulation occurs. This fluid circulation shifts the basalt-to-eclogite transition and the associated slab dehydration 14 km deeper (35 km farther landward) than would be predicted with no fluid flow. For most subduction zones, hydrothermal cooling of the subducting slab will delay eclogitization relative to estimates made without considering fluid circulation. Copyright 2009 by the American Geophysical Union.

Non-invasive, transdermal, path-selective and specific glucose monitoring via a graphene-based platform

NASA Astrophysics Data System (ADS)

Lipani, Luca; Dupont, Bertrand G. R.; Doungmene, Floriant; Marken, Frank; Tyrrell, Rex M.; Guy, Richard H.; Ilie, Adelina

2018-06-01

Currently, there is no available needle-free approach for diabetics to monitor glucose levels in the interstitial fluid. Here, we report a path-selective, non-invasive, transdermal glucose monitoring system based on a miniaturized pixel array platform (realized either by graphene-based thin-film technology, or screen-printing). The system samples glucose from the interstitial fluid via electroosmotic extraction through individual, privileged, follicular pathways in the skin, accessible via the pixels of the array. A proof of principle using mammalian skin ex vivo is demonstrated for specific and `quantized' glucose extraction/detection via follicular pathways, and across the hypo- to hyper-glycaemic range in humans. Furthermore, the quantification of follicular and non-follicular glucose extraction fluxes is clearly shown. In vivo continuous monitoring of interstitial fluid-borne glucose with the pixel array was able to track blood sugar in healthy human subjects. This approach paves the way to clinically relevant glucose detection in diabetics without the need for invasive, finger-stick blood sampling.

Supercritical fluid carbon dioxide extraction and liquid chromatographic separation with electrochemical detection of methylmercury from biological samples

USGS Publications Warehouse

Simon, N.S.

1997-01-01

Using the coupled methods presented in this paper, methylmercury can be accurately and rapidly extracted from biological samples by modified supercritical fluid carbon dioxide and quantitated using liquid chromatography with reductive electrochemical detection. Supercritical fluid carbon dioxide modified with methanol effectively extracts underivatized methylmercury from certified reference materials Dorm-1 (dogfish muscle) and Dolt-2 (dogfish liver). Calcium chloride and water, with a ratio of 5:2 (by weight), provide the acid environment required for extracting methylmercury from sample matrices. Methylmercury chloride is separated from other organomercury chloride compounds using HPLC. The acidic eluent, containing 0.06 mol L-1 NaCl, insures the presence of methylmercury chloride and facilitates the reduction of mercury on a glassy carbon electrode. If dual glassy carbon electrodes are used, a positive peak is observed at -0.65 to -0.70 V and a negative peak is observed at -0.90V with the organomercury compounds that were tested. The practical detection limit for methylmercury is 5 X 10-8 mol L-1 (1 X 10-12 tool injected) when a 20 ??L injection loop is used.

Characterisation of dissolved organic compounds in hydrothermal fluids by stir bar sorptive extraction - gas chomatography - mass spectrometry. Case study: the Rainbow field (36°N, Mid-Atlantic Ridge)

PubMed Central

2012-01-01

The analysis of the dissolved organic fraction of hydrothermal fluids has been considered a real challenge due to sampling difficulties, complexity of the matrix, numerous interferences and the assumed ppb concentration levels. The present study shows, in a qualitative approach, that Stir Bar Sorptive Extraction (SBSE) followed by Thermal Desorption – Gas Chromatography – Mass Spectrometry (TD-GC-MS) is suitable for extraction of small sample volumes and detection of a wide range of volatile and semivolatile organic compounds dissolved in hydrothermal fluids. In a case study, the technique was successfully applied to fluids from the Rainbow ultramafic-hosted hydrothermal field located at 36°14’N on the Mid-Atlantic Ridge (MAR). We show that n-alkanes, mono- and poly- aromatic hydrocarbons as well as fatty acids can be easily identified and their retention times determined. Our results demonstrate the excellent repeatability of the method as well as the possibility of storing stir bars for at least three years without significant changes in the composition of the recovered organic matter. A preliminary comparative investigation of the organic composition of the Rainbow fluids showed the great potential of the method to be used for assessing intrafield variations and carrying out time series studies. All together our results demonstrate that SBSE-TD-GC-MS analyses of hydrothermal fluids will make important contributions to the understanding of geochemical processes, geomicrobiological interactions and formation of mineral deposits. PMID:23134621

Oil and Gas Extraction Sector (NAICS 211)

EPA Pesticide Factsheets

Environmental regulatory information for oil and gas extraction sectors, including oil and natural gas drilling. Includes information about NESHAPs for RICE and stationary combustion engines, and effluent guidelines for synthetic-based drilling fluids