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Sample records for gel filtration revealed

  1. Radioimmunological determination of parathormone peptides in the plasma before and after gel filtration in hyperparathyroidic patients

    International Nuclear Information System (INIS)

    Juengst, U.

    1983-01-01

    Plasmas from different patients suffering from secondary renal hyperparathyroidism and from one patient suffering from primary hyperparathyroidism owing to a parathyroid adenoma, were studied and parathormone concentrations (total IPTH) were determined radio-immunologically. Plasmas were gel-filtered subsequently. Gelfiltration allows to separate intact PTH from PTH fragments which also occur in the plasma. These fragments also react with the antisera used in the PTH-radio-immuno-assay; thus it was possible to determine only the concentration of intact PTH after gel filtration. In patients in whose unfiltered plasma strongly increased PTH values had been measured (more than 100 pmol hPTH/l plasma), only 10 to 40% of total immunoreactivity were taken up by intact parathormone after gel filtration. Histological findings of iliac crest biopsies revealed marked changes corresponding to the increased concentration of biologically active hormone. Whereas unfiltered plasma revealed slightly increased PTH measurement values (below 100 pmol hPTH/l), 60 to 75% of total immuno reactivity was taken up by the intact hormone after gel filtration. Correspondingly, histological changes of the skeleton were less marked. Apparently, there is a correlation - though not a linear one - between total IPTH and the absolute concentration of intact PTH. If increased PTH values are measured with antiserum S478, it may be assumed in general that the concentration of intact and biologically active PTH has increased as well. (orig./MG) [de

  2. Establishment and application of milk fingerprint by gel filtration chromatography.

    Science.gov (United States)

    Gao, P; Li, J; Li, Z; Hao, J; Zan, L

    2016-12-01

    Raw milk adulteration frequently occurs in undeveloped countries. It not only reduces the nutritional value of milk, but it is also harmful to consumers. In this paper, we focused on investigating an efficient method for the quality control of raw milk protein. A gel filtration chromatography (GFC) fingerprint method combined with chemometrics was developed for fingerprint analysis of raw milk. To optimize the GFC conditions, milk fat was removed by centrifugation, and GFC analysis was performed on a Superdex 75 10/300GL column (Just Scientific, Shanghai, China) with 0.2 M NaH 2 PO 4 -Na 2 HPO 4 buffer (pH 7.0) as the mobile phase. The flow rate was 0.5mL/min, and the detection wavelength was set at 280 nm. Ten batches of 120 raw milk samples were analyzed to establish the GFC fingerprint under optimal conditions. Six major peaks common to the chromatogram of each raw milk sample were selected for fingerprint analysis, and the characteristic peaks were used to establish a standard chromatographic fingerprint. Principal component analysis was then applied to classify GFC information of adulterated milk and raw milk, allowing adulterated samples to be effectively screened out from the raw milk in principal component analysis scores plot. The fingerprint method demonstrates promising features in detecting milk protein adulteration. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  3. Purification of Peptide Components including Melittin from Bee Venom using gel filtration chromatography and propionic acid/urea polyacrylamide gel electrophoresis

    Directory of Open Access Journals (Sweden)

    Young Chon Choi

    2006-06-01

    Full Text Available Objectives : This study was conducted to carry out Purification of Melittin and other peptide components from Bee Venom using gel filtration chromatography and propionic acid/urea polyacrylamide gel electrophoresis Methods : Melittin and other peptide components were separated from bee venom by using gel filtration chromatography on Sephadex G-50 column in 0.05M ammonium acetate buffer. Results : Melittin and other peptide components were separated from bee venom by using gel filtration chromatography on Sephadex G-50 column in 0.05M ammonium acetate buffer. The fractions obtained from gel filtration chromatography was analyzed by using SDS-PAGE and propionic acid/urea polyacrylamide gel electrophoresis. The melittin obtained from the gel filtration contained residual amount of phospholipase A2 and a protein with molecular weight of 6,000. The contaminating proteins were removed by the second gel filtration chromatography. Conclusion : Gel filtration chromatography and propionic acid/urea polyacrylamide gel electrophoresis are useful to separate peptide components including melittin from bee venom.

  4. A Laboratory Exercise for Visible Gel Filtration Chromatography Using Fluorescent Proteins

    Science.gov (United States)

    Zhang, Wenqiang; Cao, Yibin; Xu, Lishan; Gong, Jufang; Sun, Meihao

    2015-01-01

    Gel filtration chromatography (GFC) separates molecules according to size and is one of the most widely used methods for protein purification. Here, red fluorescent protein (RFP), green fluorescent protein (GFP), yellow fluorescent protein (YFP), cyan fluorescent protein (CFP), and/or their fusion proteins were prokaryotically expressed, purified,…

  5. Radioimmunoassay kit formulation and its validation for serum progesterone using progesterone radiotracer purified by gel filtration

    International Nuclear Information System (INIS)

    Karir, T.; Pal, N.; Sivaprasad, N.

    2003-01-01

    Purification of the radioiodinated progesterone tyrosine methyl ester conjugate by gel filtration and the development, optimization and clinical validation of a direct radioimmunoassay (RIA) of progesterone using this radiotracer are described. High purity radiotracer is essential for the error free performance of any RIA. Progesterone 11α hemisuccinate was conjugated to tyrosine methyl ester (TME) by the mixed anhydride method and this conjugate was then radioiodinated by the chloramine-T method. Purification of the radioiodinated product was carried out by gel filtration. About 12 batches of the radiotracer were prepared and purified. The purification by gel filtration gave reproducible elution pattern and purity. The radiotracer thus purified was found to have consistent quality as compared to that of any other purification methods. Non-specific binding of the radiotracer was found to be 95% as checked by paper electrophoresis. The stability (retention of the immunoreactivity) of the radiotracer was two to three months. No appreciable changes in the assay characteristics were observed during this period. The assay involved 3 hours incubation of progesterone antibody with individual standards or sample and radiotracer at room temperature. The optimized assay was then validated for internal and external quality control parameters. A RIA kit was then formulated with this radiotracer for estimation of progesterone in serum. The assay kit consisted of lyophilized individual standards ranging from 0.25 to 50 ng/ml. The clinical performance of the developed kit was compared with that of a commercial ELISA kit and a correlation of 0.94 was observed. (author)

  6. Comparison of antimicrobial peptide purification via free-flow electrophoresis and gel filtration chromatography.

    Science.gov (United States)

    Xia, Zhi-Jun; Liu, Zhen; Kong, Fan-Zhi; Fan, Liu-Yin; Xiao, Hua; Cao, Cheng-Xi

    2017-12-01

    Antimicrobial peptides (AMPs) are usually small and cationic biomolecules with broad-spectrum antimicrobial activities against pathogens. Purifying them from complex samples is essential to study their physiochemical properties. In this work, free-flow zone electrophoresis (FFZE) was utilized to purify AMPs from yeast fermentation broth. Meanwhile, gel filtration chromatography (GFC) was conducted for comparison. The separation efficiency was evaluated by SDS-PAGE analysis of the fractions from both methods. Our results demonstrated as follows: (i) FFZE had more than 30-fold higher processing capacity as compared with GFC; (ii) FFZE could achieve 87% purity and 89% recovery rate while in GFC these parameters were about 93 and 82%, respectively; (iii) the former had ∼2-fold dilution but the latter had ∼13-fold dilution. Furthermore, Tricine-SDS-PAGE, Native-PAGE, and gel IEF were carried out to characterize the purified AMPs. We found that two peptides existed as a pair with the molecular mass of ∼5.5 and 7.0 kDa, while the same pI 7.8. These two peptides were proved to have the antimicrobial activity through the standardized agar diffusion method. Therefore, FFZE could be used to continuously purify AMPs with high bioactivity, which will lead to its wide application in the clinical and pharmaceutical fields. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Purification of adenoviral vectors by combined anion exchange and gel filtration chromatography.

    Science.gov (United States)

    Eglon, Marc N; Duffy, Aoife M; O'Brien, Timothy; Strappe, Padraig M

    2009-11-01

    Adenoviral vectors are used extensively in human gene therapy trials and in vaccine development. Large-scale GMP production requires a downstream purification process, and liquid chromatography is emerging as the most powerful mode of purification, enabling the production of vectors at a clinically relevant scale and quality. The present study describes the development of a two-step high-performance liquid chromatography (HPLC) process combining anion exchange (AIEX) and gel filtration (GF) in comparison with the caesium chloride density gradient method. HEK-293 cells were cultured in ten-layer CellStacks() and infected with 10 pfu/cell of adenoviral vector expressing green fluorescent protein (Ad5-GFP). Cell-bound virus was harvested and benzonase added to digest DNA, crude lysate was clarified by centrifugation and filtration prior to HPLC. Chromatography fractions were added to HEK-293 cells and GFP expression measured using a fluorescent plate reader. Using AIEX then GF resulted in an adenoviral vector with purity comparable to Ad5-GFP purified by CsCl, whereas the reverse process (GF-AIEX) showed a reduced purity by electrophoresis and required further buffer exchange of the product. The optimal process (AIEX-GF) resulted in a vector yield of 2.3 x 10(7) pfu/cm(2) of cell culture harvested compared to 3.3 x 10(7) pfu/cm(2) for CsCl. The process recovery for the HPLC process was 36% compared to 27.5% for CsCl and total virion to infectious particle ratios of 18 and 11, respectively, were measured. We present a simple two-step chromatography process that is capable of producing high-quality adenovirus at a titre suitable for scale-up and clinical translation.

  8. Studies of the effect of ethanol and sodium chloride on the micellization of sodium dodecyl sulfate by gel filtration

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, H.

    1976-06-01

    The effects of the addition of ethanol and sodium chloride to aqueous solutions of sodium dodecyl sulfate (SDS) were studied by the gel-filtration method. With an increase in the concentration of ethanol, the CMC decreased and then increased after passing a minimum, while the micellar weight increased and then decreased, showing a corresponding maximum. Above about 40 vol percent ethanol, no micelle formation was observed. The micellar weight and aggregation number in the presence of ethanol were measured in the SDS concentration range of a constant elution rate of micelles. A decrease in the CMC and an increase in the micellar weight of SDS were observed with an increase in the concentration of NaCl from 0 to 10 mmol/l. The gel-filtration study enabled us to make a direct experimental confirmation of the effects of ethanol and NaCl on the micelle formation of SDS.

  9. Comparison of acid ethanol extraction and acid gel filtration prior to IGF-I and IGF-II radioimmunoassays

    International Nuclear Information System (INIS)

    Bang, P.; Eriksson, U.; Wivall, I.-L.; Hall, K.; Sara, V.

    1991-01-01

    Insulin-like growth factor binding proteins interfere in the IGF-I and -II radioimmunoassays. In an attempt to overcome this problem, we have compared the use of truncated IGF-I, with reduced IGFBP affinity, and IGF-I as radioligands for IGF-I RIA measurements in serum separated by acid gel filtration or acid ethanol extraction followed by cryo-precipitation. With truncated IGF-I as radioligand the IGF-I measurements in acid gel filtrates and acid ethanol extracts were significantly correlated in healthy subjects (N=42, r=0.91, p<0.001) and in patients with acromegaly (N=10, r=0.85, p<0.01), GH deficiency (N=10, r=0.88, p<0.001) or Type I diabetes mellitus (N=10, r=0.90, p<0.001). In contrast, the IGF-I concentrations in acid ethanol extracts determined with IGF-I as radioligand did not correlate with those in acid gel filtrates using truncated IGF-I radioligand in patients with acromegaly (r=0.61, NS) or GH deficiency (r=0.46, NS). In the latter group the mean IGF-I concentrations measured in acid ethanol extracts were erroneously elevated by 112%. Low-affinity antibodies used for IGF-II RIA determinations failed to give reliable results in acid ethanol extracts from patients with Type I diabetes mellitus or GH deficiency. In conclusion, erroneously high IGF-I concentrations owing to binding of the radioligand to IGFBPs not completely removed by acid ethanol extraction can be avoided by the use of truncated IGF-I as radioligand. (author)

  10. Second-order Data by Flow Injection Analysis with Spectrophotometric Diode-array Detection and Incorporated Gel-filtration Chromatographic Column

    DEFF Research Database (Denmark)

    Bechmann, Iben Ellegaard

    1997-01-01

    A flow injection analysis (FIA) system furnished with a gel-filtration chromatographic column and with photodiode-array detection was used for the generation of second-order data. The system presented is a model system in which the analytes are blue dextran, potassium hexacyanoferrate(III) and he......A flow injection analysis (FIA) system furnished with a gel-filtration chromatographic column and with photodiode-array detection was used for the generation of second-order data. The system presented is a model system in which the analytes are blue dextran, potassium hexacyanoferrate...

  11. Determination of formaldehyde in frozen fish with formaldehyde dehydrogenase using a flow injection system with an incorporated gel-filtration chromatrography column

    DEFF Research Database (Denmark)

    Bechmann, Iben Ell

    1996-01-01

    in a FIA system. The FIA system is furnished with a gel-filtration chromatography column for on-line removal of the proteins from the extract before the enzymatic analysis is performed. Compared with the standard methods for determination of formaldehyde in fish products the present method is much faster...

  12. Determination of Formaldehyde in Frozen Fish with Formaldehyde Dehydrogenase Using a Flow Injection System with an Incorporated Gel-filtration Chromatography Column

    DEFF Research Database (Denmark)

    Bechmann, Iben Ellegaard

    1996-01-01

    in a FIA system. The FIA system is furnished with a gel-filtration chromatography column for on-line removal of the proteins from the extract before the enzymatic analysis is performed. Compared with the standard methods for determination of formaldehyde in fish products the present method is much faster...

  13. An improved method for purification of recombinant truncated heme oxygenase-1 by expanded bed adsorption and gel filtration.

    Science.gov (United States)

    Hu, Hong-Bo; Wang, Wei; Han, Ling; Zhou, Wen-Pu; Zhang, Xue-Hong

    2007-03-01

    Recombinant truncated human heme oxygenase-1 (hHO-1) expressed in Escherichia coli was efficiently separated and purified from feedstock by DEAE-ion exchange expanded bed adsorption. Protocol optimization of hHO-1 on DEAE adsorbent resulted in adsorption in 0 M NaCl and elution in 150 mM NaCl at a pH of 8.5. The active enzyme fractions separated from the expanded bed column were further purified by a Superdex 75 gel filtration step. The specific hHO-1 activity increased from 0.82 +/- 0.05 to 24.8 +/- 1.8 U/mg during the whole purification steps. The recovery and purification factor of truncated hHO-1 of the whole purification were 72.7 +/- 4.7 and 30.2 +/- 2.3%, respectively. This purification process can decrease the demand on the preparation of feedstock and simplify the purification process.

  14. Titania and Zinc Oxide Nanoparticles: Coating with Polydopamine and Encapsulation within Lecithin Liposomes—Water Treatment Analysis by Gel Filtration Chromatography with Fluorescence Detection

    Directory of Open Access Journals (Sweden)

    Xuhao Zhao

    2018-02-01

    Full Text Available The interplay of metal oxide nanoparticles, environmental pollution, and health risks is key to all industrial and drinking water treatment processes. In this work we present a study using gel filtration chromatography for the analytical investigation of metal oxide nanoparticles in water, their coating with polydopamine, and their encapsulation within lecithin liposomes. Polydopamine prevents TiO2 and ZnO nanoparticles from aggregation during chromatographic separation. Lecithin forms liposomes that encapsulate the nanoparticles and carry them through the gel filtration column, producing an increase of peak area for quantitative analysis without any change in retention time to affect qualitative identification. To the best of our knowledge, this is the first report that demonstrates the potential application of lecithin liposomes for cleaning up metal oxide nanoparticles in water treatment. Encapsulation of graphene quantum dots by liposomes would allow for monitoring of nanoparticle-loaded liposomes to ensure their complete removal by membrane ultrafiltration from treated water.

  15. Transmission X-ray microscopy (TXM) reveals the nanostructure of a smectite gel.

    Science.gov (United States)

    Zbik, Marek S; Martens, Wayde N; Frost, Ray L; Song, Yen-Fang; Chen, Yi-Ming; Chen, Jian-Hua

    2008-08-19

    The unusual behavior of smectites, the ability to change volume when wetted (swelling) or dried (shrinking), makes soil rich in smectites very unstable and dangerous for the building industry because of the movement of building foundations and poor slope stability. These macroscopic properties are dominated by the structural arrangement of the smectites' finest fraction. Here, we show in three dimensions how the swelling phenomenon in smectite, caused by a combination of hydratation and electrostatic forces, may expand the dry smectite volume not 10-fold, as previously thought, but to more than 1000-fold. A new technique, transmission X-ray microscopy, makes it possible to investigate the internal structure and 3-D tomographic reconstruction of clay aggregates. This reveals, for the first time, the smectite gel arrangement in the voluminous cellular tactoid structure within a natural aqueous environment.

  16. Comparison of acid ethanol extraction and acid gel filtration prior to IGF-I and IGF-II radioimmunoassays; Improvement of determinations in acid ethanol extracts by the use of truncated IGF-I as radioligand

    Energy Technology Data Exchange (ETDEWEB)

    Bang, P; Eriksson, U; Wivall, I -L; Hall, K [Department of Endocrinology, Karolinska Institute, Stockholm (Sweden); Sara, V [Department of Pathology, Karolinska Institute, Stockholm (Sweden)

    1991-01-01

    Insulin-like growth factor binding proteins interfere in the IGF-I and -II radioimmunoassays. In an attempt to overcome this problem, we have compared the use of truncated IGF-I, with reduced IGFBP affinity, and IGF-I as radioligands for IGF-I RIA measurements in serum separated by acid gel filtration or acid ethanol extraction followed by cryo-precipitation. With truncated IGF-I as radioligand the IGF-I measurements in acid gel filtrates and acid ethanol extracts were significantly correlated in healthy subjects (N=42, r=0.91, p<0.001) and in patients with acromegaly (N=10, r=0.85, p<0.01), GH deficiency (N=10, r=0.88, p<0.001) or Type I diabetes mellitus (N=10, r=0.90, p<0.001). In contrast, the IGF-I concentrations in acid ethanol extracts determined with IGF-I as radioligand did not correlate with those in acid gel filtrates using truncated IGF-I radioligand in patients with acromegaly (r=0.61, NS) or GH deficiency (r=0.46, NS). In the latter group the mean IGF-I concentrations measured in acid ethanol extracts were erroneously elevated by 112%. Low-affinity antibodies used for IGF-II RIA determinations failed to give reliable results in acid ethanol extracts from patients with Type I diabetes mellitus or GH deficiency. In conclusion, erroneously high IGF-I concentrations owing to binding of the radioligand to IGFBPs not completely removed by acid ethanol extraction can be avoided by the use of truncated IGF-I as radioligand. (author).

  17. Characterisation of Maillard reaction products derived from LEKFD--a pentapeptide found in β-lactoglobulin sequence, glycated with glucose--by tandem mass spectrometry, molecular orbital calculations and gel filtration chromatography coupled with continuous photodiode array.

    Science.gov (United States)

    Yamaguchi, Keiko; Homma, Takeshi; Nomi, Yuri; Otsuka, Yuzuru

    2014-02-15

    Maillard reaction peptides (MRPs) contribute to taste, aroma, colour, texture and biological activity. However, peptide degradation or the cross-linking of MRPs in the Maillard reaction has not been investigated clearly. A peptide of LEKFD, a part of β-lactoglobulin, was heated at 110 °C for 24h with glucose and the reaction products were analysed by HPLC with ODS, ESI-MS, ESI-MS/MS and HPLC with gel-filtration column and DAD detector. In the HPLC fractions, an imminium ion of LEK*FD, a pyrylium ion or a hydroxymethyl furylium ion of LEK*FD, and KFD and EK were detected by ESI-MS. Therefore, those products may be produced by the Maillard reaction. The molecular orbital of glycated LEKFD at the lysine epsilon-amino residue with Schiff base form was calculated by MOPAC. HPLC with gel-filtration column showed cross-linking and degradation of peptides. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Agarose gel shift assay reveals that calreticulin favors substrates with a quaternary structure in solution

    DEFF Research Database (Denmark)

    Boelt, Sanne Grundvad; Houen, Gunnar; Højrup, Peter

    2015-01-01

    Here we present an agarose gel shift assay that, in contrast to other electrophoresis approaches, is loaded in the center of the gel. This allows proteins to migrate in either direction according to their isoelectric points. Therefore, the presented assay enables a direct visualization, separation...... structure. It is also demonstrated that the agarose gel shift assay is useful in the study of other protein interactions and can be used as an alternative method to native polyacrylamide gel electrophoresis....... measure of interactions. Therefore, no interaction studies between calreticulin and substrates in solution have been investigated previously. The results presented here indicate that calreticulin has a preference for substrates with a quaternary structure and primarily β-sheets in their secondary...

  19. Brain networks engaged in audiovisual integration during speech perception revealed by persistent homology-based network filtration.

    Science.gov (United States)

    Kim, Heejung; Hahm, Jarang; Lee, Hyekyoung; Kang, Eunjoo; Kang, Hyejin; Lee, Dong Soo

    2015-05-01

    The human brain naturally integrates audiovisual information to improve speech perception. However, in noisy environments, understanding speech is difficult and may require much effort. Although the brain network is supposed to be engaged in speech perception, it is unclear how speech-related brain regions are connected during natural bimodal audiovisual or unimodal speech perception with counterpart irrelevant noise. To investigate the topological changes of speech-related brain networks at all possible thresholds, we used a persistent homological framework through hierarchical clustering, such as single linkage distance, to analyze the connected component of the functional network during speech perception using functional magnetic resonance imaging. For speech perception, bimodal (audio-visual speech cue) or unimodal speech cues with counterpart irrelevant noise (auditory white-noise or visual gum-chewing) were delivered to 15 subjects. In terms of positive relationship, similar connected components were observed in bimodal and unimodal speech conditions during filtration. However, during speech perception by congruent audiovisual stimuli, the tighter couplings of left anterior temporal gyrus-anterior insula component and right premotor-visual components were observed than auditory or visual speech cue conditions, respectively. Interestingly, visual speech is perceived under white noise by tight negative coupling in the left inferior frontal region-right anterior cingulate, left anterior insula, and bilateral visual regions, including right middle temporal gyrus, right fusiform components. In conclusion, the speech brain network is tightly positively or negatively connected, and can reflect efficient or effortful processes during natural audiovisual integration or lip-reading, respectively, in speech perception.

  20. Gel-free proteomics reveal potential biomarkers of priming-induced salt tolerance in durum wheat.

    Science.gov (United States)

    Fercha, Azzedine; Capriotti, Anna Laura; Caruso, Giuseppe; Cavaliere, Chiara; Gherroucha, Hocine; Samperi, Roberto; Stampachiacchiere, Serena; Lagana, Aldo

    2013-10-08

    Seed priming has been successfully demonstrated to be an efficient method to improve crop productivity under stressful conditions. As a first step toward better understanding of the mechanisms underlying the priming-induced salt stress tolerance in durum wheat, and to overcome the limitations of the gel-based approach, a comparative gel-free proteomic analysis was conducted with durum wheat seed samples of varying vigor as generated by hydro- and ascorbate-priming treatments. Results indicate that hydro-priming was accompanied by significant changes of 72 proteins, most of which are involved in proteolysis, protein synthesis, metabolism and disease/defense response. Ascorbate-priming was, however, accompanied by significant changes of 83 proteins, which are mainly involved in protein metabolism, antioxidant protection, repair processes and, interestingly, in methionine-related metabolism. The present study provides new information for understanding how 'priming-memory' invokes seed stress tolerance. The current work describes the first study in which gel-free shotgun proteomics were used to investigate the metabolic seed protein fraction in durum wheat. A combined approach of protein fractionation, hydrogel nanoparticle enrichment technique, and gel-free shotgun proteomic analysis allowed us to identify over 380 proteins exhibiting greater molecular weight diversity (ranging from 7 to 258kDa). Accordingly, we propose that this approach could be useful to acquire a wider perspective and a better understanding of the seed proteome. In the present work, we employed this method to investigate the potential biomarkers of priming-induced salt tolerance in durum wheat. In this way, we identified several previously unrecognized proteins which were never been reported before, particularly for the ascorbate-priming treatment. These findings could provide new avenues for improving crop productivity, particularly under unfavorable environmental conditions. © 2013.

  1. Ultrastructure of a hexagonal array in exosporium of a highly sporogenic mutant of Clostridium botulinum type A revealed by electron microscopy using optical diffraction and filtration.

    Science.gov (United States)

    Masuda, K; Kawata, T; Takumi, K; Kinouchi, T

    1980-01-01

    The ultrastructure of a hexagonal array in the exosporium from spores of a highly sporogenic mutant of Clostridium botulinum type A strain 190L was studied by electron microscopy of negatively stained exosporium fragments using optical diffraction and filtration. The exosporium was composed of three or more lamellae showing and equilateral, hexagonal periodicity. Images of the single exosporium layer from which the noise had been filtered optically revealed that the hexagonally arranged, morphological unit of the exosporium was composed of three globular subunits about 2.1 nm in diameter which were arranged at the vertices of an equilateral triangle with sides of about 2.4 nm. The morphological units were arranged with a spacing of about 4.5 nm. the adjacent globular subunits appeared to be interconnected by delicate linkers.

  2. Aerosol filtration

    International Nuclear Information System (INIS)

    First, M.W.; Gilbert, H.

    1982-01-01

    Significant developments in high-efficiency filtration for nuclear applications are reviewed for the period 1968 to 1980. Topics of special interest include (1) factory (bench) and in-place test methods, (2) new developments in paper and filter unit construction methods, (3) vented containment air cleaning systems for liquid-metal fast breeder reactors and light-water-moderated reactors, and (4) decontamination of off-gases from nuclear waste volume-reduction processes. Standards development has been vigorously pursued during this period, but advances in filtration theory have been few. One of the significant changes likely to occur in the immediate future is adoption of the European style of high-efficiency particulate air filters instead of those which have been in service for the past three decades to obtain the benefits of having almost twice as much filter paper in the same filter cartridge

  3. Aerosol filtration

    International Nuclear Information System (INIS)

    First, M.W.; Gilbert, H.

    1981-01-01

    Significant developments in high efficiency filtration for nuclear applications are reviewed for the period 1968 to 1980. Topics of special interest include factory (bench) and in-place test methods, new developments in paper and filter unit construction methods, vented containment air cleaning systems for LMFBR and light water moderated reactors, and decontamination of offgases from nuclear waste volume reduction processes. It is noted that standards development has been vigorously pursued during this period but that advances in filtration theory have been few. One of the significant changes likely to occur in the immediate future is adoption of the European style of HEPA filters for those that have been in service for the past three decades to obtain the benefits of having almost twice as much filter paper in the same filter cartridge. 71 references

  4. Agarose Gel Electrophoresis Reveals Structural Fluidity of a Phage T3 DNA Packaging Intermediate

    Science.gov (United States)

    Serwer, Philip; Wright, Elena T.

    2012-01-01

    We find a new aspect of DNA packaging-associated structural fluidity for phage T3 capsids. The procedure is (1) glutaraldehyde cross-linking of in vivo DNA packaging intermediates for stabilization of structure and then (2) determining of effective radius by two-dimensional agarose gel electrophoresis (2d-AGE). The intermediates are capsids with incompletely packaged DNA (ipDNA) and without an external DNA segment; these intermediates are called ipDNA-capsids. We initially increase production of ipDNA-capsids by raising NaCl concentration during in vivo DNA packaging. By 2d-AGE, we find a new state of contracted shell for some particles of one previously identified ipDNA-capsid. The contracted shell-state is found when ipDNA length/mature DNA length (F) is above 0.17, but not at lower F. Some contracted-shell ipDNA-capsids have the phage tail; others do not. The contracted-shell ipDNA-capsids are explained by premature DNA maturation cleavage that makes accessible a contracted-shell intermediate of a cycle of the T3 DNA packaging motor. The analysis of ipDNA-capsids, rather than intermediates with uncleaved DNA, provides a simplifying strategy for a complete biochemical analysis of in vivo DNA packaging. PMID:22222979

  5. Agarose gel electrophoresis reveals structural fluidity of a phage T3 DNA packaging intermediate.

    Science.gov (United States)

    Serwer, Philip; Wright, Elena T

    2012-01-01

    We find a new aspect of DNA packaging-associated structural fluidity for phage T3 capsids. The procedure is (i) glutaraldehyde cross-linking of in vivo DNA packaging intermediates for the stabilization of structure and then (ii) determining effective radius by two-dimensional agarose gel electrophoresis (2D-AGE). The intermediates are capsids with incompletely packaged DNA (ipDNA) and without an external DNA segment; these intermediates are called ipDNA-capsids. We initially increase the production of ipDNA-capsids by raising NaCl concentration during in vivo DNA packaging. By 2D-AGE, we find a new state of contracted shell for some particles of one previously identified ipDNA-capsid. The contracted shell-state is found when the ipDNA length/mature DNA length (F) is above 0.17, but not at lower F. Some contracted-shell ipDNA-capsids have the phage tail; others do not. The contracted-shell ipDNA-capsids are explained by premature DNA maturation cleavage that makes accessible a contracted-shell intermediate of a cycle of the T3 DNA packaging motor. The analysis of ipDNA-capsids, rather than intermediates with uncleaved DNA, provides a simplifying strategy for a complete biochemical analysis of in vivo DNA packaging. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Aerosol filtration

    International Nuclear Information System (INIS)

    Klein, M.; Goossens, W.R.A.; De Smet, M.; Trine, J.; Hertschap, M.

    1984-01-01

    This report summarizes the work on the development of fibre metallic prefilters to be placed upstream of HEPA filters for the exhaust gases of nuclear process plants. Investigations at ambient and high temperature were carried out. Measurements of the filtration performance of Bekipor porous webs and sintered mats were performed in the AFLT (aerosol filtration at low temperature) unit with a throughput of 15 m 3 /h. A parametric study on the influence of particle size, fibre diameter, number of layers and superficial velocity led to the optimum choice of the working parameters. Three selected filter types were then tested with polydisperse aerosols using a candle-type filter configuration or a flat-type filter configuration. The small-diameter candle type is not well suited for a spraying nozzles regeneration system so that only the flat-type filter was retained for high-temperature tests. A high-temperature test unit (AFHT) with a throughput of 8 to 10 m 3 /h at 400 0 C was used to test the three filter types with an aerosol generated by high-temperature calcination of a simulated nitric acid waste solution traced with 134 Cs. The regeneration of the filter by spray washing and the effect of the regeneration on the filter performance was studied for the three filter types. The porous mats have a higher dust loading capacity than the sintered web which means that their regeneration frequency can be kept lower

  7. GSPEL - Air Filtration Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Evaluation capabilities for air filtration devicesThe Air Filtration Lab provides testing of air filtration devices to demonstrate and validate new or legacy system...

  8. Denaturing gradient gel electrophoresis and barcoded pyrosequencing reveal unprecedented archaeal diversity in mangrove sediment and rhizosphere samples.

    Science.gov (United States)

    Pires, Ana C C; Cleary, Daniel F R; Almeida, Adelaide; Cunha, Angela; Dealtry, Simone; Mendonça-Hagler, Leda C S; Smalla, Kornelia; Gomes, Newton C M

    2012-08-01

    Mangroves are complex ecosystems that regulate nutrient and sediment fluxes to the open sea. The importance of bacteria and fungi in regulating nutrient cycles has led to an interest in their diversity and composition in mangroves. However, very few studies have assessed Archaea in mangroves, and virtually nothing is known about whether mangrove rhizospheres affect archaeal diversity and composition. Here, we studied the diversity and composition of Archaea in mangrove bulk sediment and the rhizospheres of two mangrove trees, Rhizophora mangle and Laguncularia racemosa, using denaturing gradient gel electrophoresis (DGGE) and pyrosequencing of archaeal 16S rRNA genes with a nested-amplification approach. DGGE profiles revealed significant structural differences between bulk sediment and rhizosphere samples, suggesting that roots of both mangrove species influence the sediment archaeal community. Nearly all of the detected sequences obtained with pyrosequencing were identified as Archaea, but most were unclassified at the level of phylum or below. Archaeal richness was, furthermore, the highest in the L. racemosa rhizosphere, intermediate in bulk sediment, and the lowest in the R. mangle rhizosphere. This study shows that rhizosphere microhabitats of R. mangle and L. racemosa, common plants in subtropical mangroves located in Rio de Janeiro, Brazil, hosted distinct archaeal assemblages.

  9. Benchmarking sample preparation/digestion protocols reveals tube-gel being a fast and repeatable method for quantitative proteomics.

    Science.gov (United States)

    Muller, Leslie; Fornecker, Luc; Van Dorsselaer, Alain; Cianférani, Sarah; Carapito, Christine

    2016-12-01

    Sample preparation, typically by in-solution or in-gel approaches, has a strong influence on the accuracy and robustness of quantitative proteomics workflows. The major benefit of in-gel procedures is their compatibility with detergents (such as SDS) for protein solubilization. However, SDS-PAGE is a time-consuming approach. Tube-gel (TG) preparation circumvents this drawback as it involves directly trapping the sample in a polyacrylamide gel matrix without electrophoresis. We report here the first global label-free quantitative comparison between TG, stacking gel (SG), and basic liquid digestion (LD). A series of UPS1 standard mixtures (at 0.5, 1, 2.5, 5, 10, and 25 fmol) were spiked in a complex yeast lysate background. TG preparation allowed more yeast proteins to be identified than did the SG and LD approaches, with mean numbers of 1979, 1788, and 1323 proteins identified, respectively. Furthermore, the TG method proved equivalent to SG and superior to LD in terms of the repeatability of the subsequent experiments, with mean CV for yeast protein label-free quantifications of 7, 9, and 10%. Finally, known variant UPS1 proteins were successfully detected in the TG-prepared sample within a complex background with high sensitivity. All the data from this study are accessible on ProteomeXchange (PXD003841). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. A spectrophotometer-based diffusivity assay reveals that diffusion hindrance of small molecules in extracellular matrix gels used in 3D cultures is dominated by viscous effects.

    Science.gov (United States)

    Galgoczy, Roland; Pastor, Isabel; Colom, Adai; Giménez, Alicia; Mas, Francesc; Alcaraz, Jordi

    2014-08-01

    The design of 3D culture studies remains challenging due to the limited understanding of extracellular matrix (ECM)-dependent hindered diffusion and the lack of simple diffusivity assays. To address these limitations, we set up a cost-effective diffusivity assay based on a Transwell plate and the spectrophotometer of a Microplate Reader, which are readily accessible to cell biology groups. The spectrophotometer-based assay was used to assess the apparent diffusivity D of FITC-dextrans with molecular weight (4-70kDa) spanning the physiological range of signaling factors in a panel of acellular ECM gels including Matrigel, fibrin and type I collagen. Despite their technical differences, D data exhibited ∼15% relative difference with respect to FRAP measurements. Our results revealed that diffusion hindrance of small particles is controlled by the enhanced viscosity of the ECM gel in conformance with the Stokes-Einstein equation rather than by geometrical factors. Moreover, we provided a strong rationale that the enhanced ECM viscosity is largely contributed to by unassembled ECM macromolecules. We also reported that gels with the lowest D exhibited diffusion hindrance closest to the large physiologic hindrance of brain tissue, which has a typical pore size much smaller than ECM gels. Conversely, sparse gels (≤1mg/ml), which are extensively used in 3D cultures, failed to reproduce the hindered diffusion of tissues, thereby supporting that dense (but not sparse) ECM gels are suitable tissue surrogates in terms of macromolecular transport. Finally, the consequences of reduced diffusivity in terms of optimizing the design of 3D culture experiments were addressed in detail. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Cross-flow filtration and axial filtration

    International Nuclear Information System (INIS)

    Kraus, K.A.

    1974-01-01

    Two relatively novel alternative solid-liquid-separation techniques of filtration are discussed. In cross-flow filtration, the feed is pumped past the filtering surface. While in axial filtration the filter, mounted on a rotor, is moved with respect to the feed. While large-scale application of the axial filter is still in doubt, it permits with little expenditure of time and money, duplication of many hydrodynamic aspects of cross-flow filtration for fine-particle handling problems. The technique has been applied to municipal wastes, low-level radioactive waste treatment plant, lead removal from industrial wastes, removal of pulp-mill contaminants, textile-mill wastes, and pretreatment of saline waters by lime-soda process in preparation for hyperfiltration. Economics and energy requirements are also discussed

  12. Maintenance of neural activities in torpid Rhinolophus ferrumequinum bats revealed by 2D gel-based proteome analysis.

    Science.gov (United States)

    Yin, Qiuyuan; Zhang, Yijian; Dong, Dong; Lei, Ming; Zhang, Shuyi; Liao, Chen-Chung; Pan, Yi-Hsuan

    2017-08-01

    Bats are the only mammals capable of self-powered flying. Many bat species hibernate in winter. A reversible control of cerebral activities is critical for bats to accommodate a repeated torpor-arousal cycle during hibernation. Little is known about the molecular mechanisms that regulate neuronal activities in torpid bats. In this study, Rhinolophus ferrumequinum bat brain proteins were fractionated, and their abundance in active and torpid states was compared. Results of 2D gel-based proteomics showed that 38% of identified proteins with a significant change in abundance are involved in synaptic vesicle recycling and cytoskeletal integrity. Changes in the abundance of proteins related to RNA splicing, proteostasis, redox homeostasis, mitochondrial function, and energy metabolism were also detected. In addition, the levels of GNAO1 (guanine nucleotide-binding protein G αo subunit), an important modulator of neuronal transmembrane signaling, were significantly increased in the insoluble protein fraction of torpid bats; this may be due to GNAO1 palmitoylation making it insoluble. Our data provide molecular evidence for the maintenance of neuronal activities in torpid bats and suggest that a reversible palmitoylation of the G protein plays a role in the regulation of neuronal activities during bat hibernation. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Magnetic-seeding filtration

    International Nuclear Information System (INIS)

    Ying, T.Y.; Chin, C.J.; Lu, S.C.; Yiacoumi, S.

    1997-10-01

    Magnetic-seeding filtration consists of two steps: heterogeneous particle flocculation of magnetic and nonmagnetic particles in a stirred tank and high-gradient magnetic filtration (HGMF). The effects of various parameters affecting magnetic-seeding filtration (HGMF). The effects of various parameters affecting magnetic seeding filtration are theoretically and experimentally investigated. A trajectory model that includes hydrodynamic resistance, van der Waals, and electrostatic forces is developed to calculate the flocculation frequency in a turbulent-shear regime. Fractal dimension is introduced to simulate the open structure of aggregates. A magnetic-filtration model that consists of trajectory analysis, a particle build-up model, a breakthrough model, and a bivariate population-balance model is developed to predict the breakthrough curve of magnetic-seeding filtration. A good agreement between modeling results and experimental data is obtained. The results show that the model developed in this study can be used to predict the performance of magnetic-seeding filtration without using empirical coefficients or fitting parameters. 35 refs., 7 figs., 1 tab

  14. PROBLEMS OF NONSTATIONARY FILTRATION

    Directory of Open Access Journals (Sweden)

    Vsevolod A. Shabanov

    2018-03-01

    Full Text Available he article deals with the classical hydrodynamic theory of filtration. Discusses models of soil, fluid and nature of fluid flow that formed the basis for the creation of the classic filtration theory. Also discusses the assumptions made for the linearization of the equations. Evaluated the scope of the classical filtration theory. Proposed a new model of filtration through a porous medium, based on the application of the laws of theoretical mechanics. It is based on the classical model of soil: the soil is composed of capillaries with ..parallel axes, in which the liquid moves. For tasks of infiltration equations of motion. Considered special cases of unsteady motion of a finite volume of liquid. Numerical example a machine experiment.

  15. Filtration in Porous Media

    DEFF Research Database (Denmark)

    Yuan, Hao; Shapiro, Alexander

    There is a considerable and ongoing effort aimed at understanding the transport and the deposition of suspended particles in porous media, especially non-Fickian transport and non-exponential deposition of particles. In this work, the influential parameters in filtration models are studied...... to understand their effects on the non-Fickian transport and the non-exponential deposition. The filtration models are validated by the comparisons between the modelling results and the experimental data.The elliptic equation with distributed filtration coefficients may be applied to model non-Fickian transport...... and hyperexponential deposition. The filtration model accounting for the migration of surface associated particles may be applied for non-monotonic deposition....

  16. Water Filtration Products

    Science.gov (United States)

    1986-01-01

    American Water Corporation manufactures water filtration products which incorporate technology originally developed for manned space operations. The formula involves granular activated charcoal and other ingredients, and removes substances by catalytic reactions, mechanical filtration, and absorption. Details are proprietary. A NASA literature search contributed to development of the compound. The technology is being extended to a deodorizing compound called Biofresh which traps gas and moisture inside the unit. Further applications are anticipated.

  17. Filtration approach to mitigate indoor Thoron progeny concentration

    International Nuclear Information System (INIS)

    Wang, J.; Meisenberg, O.; Karg, E.; Tschiersch, J.; Chen, Y.

    2010-01-01

    This study investigates filtration of air as potential mitigation method of thoron progeny exposure. The experiments were conducted in a model room (volume 7.1 m 3 ) which was equipped with a pump and an HEPA (high efficiency particulate air) filter. Filtration at a rate of 0.2, 0.4, 0.5 and 0.8 h -1 during 88 h proved an effective practice in reducing the total indoor thoron decay product concentration. The results indicate that 0.4-0.8 h -1 filtration rate had almost the same filtration efficiency in decreasing the total thoron EEC (equilibrium equivalent concentration) by 97% while 80% of total thoron EEC were reduced by 0.2 h -1 filtration rate; meanwhile, the unattached thoron EEC rose significantly by 190, 270, 290%, respectively under 0.4-0.8 h -1 filtration rate, whereas 0.2 h -1 filtration rate increased unattached thoron EEC by 40%. The aerosol number size distribution variation reveals that filtration operation removes smaller particles faster or earlier than the larger ones. The annual effective dose calculated was reduced by 91-92% at a filtration rate of 0.4-0.8 h -1 while 75% reduced at 0.2 h -1 filtration rate after 88 h filtration process. (authors)

  18. Filtration by eyelashes

    Science.gov (United States)

    Vistarakula, Krishna; Bergin, Mike; Hu, David

    2010-11-01

    Nearly every mammalian and avian eye is rimmed with lashes. We investigate experimentally the ability of lashes to reduce airborne particle deposition in the eye. We hypothesize that there is an optimum eyelash length that maximizes both filtration ability and extent of peripheral vision. This hypothesis is tested using a dual approach. Using preserved heads from 36 species of animals at the American Museum of Natural History, we determine the relationship between eye size and eyelash geometry (length and spacing). We test the filtration efficacy of these geometries by deploying outdoor manikins and measuring particle deposition rate as a function of eyelash length.

  19. Magnetic-seeding filtration

    International Nuclear Information System (INIS)

    Depaoli, D.

    1996-01-01

    This task will investigate the capabilities of magnetic-seeding filtration for the enhanced removal of magnetic and nonmagnetic particulates from liquids. This technology appies to a wide range of liquid wastes, including groundwater, process waters, and tank supernatant. Magnetic-seeding filtration can be used in several aspects of treatment, such as (1) removal of solids, particularly those in the colloidal-size range that are difficult to remove by conventional means; (2) removal of contaminants by precipitation processes; and (3) removal of contaminants by sorption processes

  20. Water Treatment Technology - Filtration.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on filtration provides instructional materials for six competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: purposes of sedimentation basins and flocculation…

  1. Epidemiological Characteristics and Clinical Treatment Outcome of Typhoid Fever in Ningbo, China, 2005-2014: Pulsed-Field Gel Electorophoresis Results Revealing Great Proportion of Common Transmission Sources.

    Science.gov (United States)

    Song, Qifa; Yang, Yuanbin; Lin, Wenping; Yi, Bo; Xu, Guozhang

    2017-09-25

    We aimed to describe the molecular epidemiological characteristics and clinical treatment outcome of typhoid fever in Ningbo, China during 2005-2014. Eighty-eight Salmonella Typhi isolates were obtained from 307 hospitalized patients. Three prevalent pulsed-field gel electrophoresis (PFGE) patterns of 54 isolates from 3 outbreaks were identified. Overall, there were 64 (72.7%) isolates from clustered cases and 24 (27.3%) isolates from sporadic cases. Resistance to nalidixic acid (NAL) (n = 47; 53.4%) and ampicillin (AMP) (n = 40; 45.4%) and rare resistance to tetracycline (TET) (n = 2; 2.3%) and gentamicin (GEN) (n = 2; 2.3%) were observed. No isolates resistant to cefotaxime (CTX), chloramphenicol (CL), ciprofloxacin (CIP), and trimethoprim-sulfamethoxazole (SXT) were found. The occurrence of reduced sensitivity to CIP was 52.3% (n = 46). The medians of fever clearance time in cases with and without complications were 7 (interquartile range (IQR): 4-10) and 5 (IQR: 3-7) days (P = 0.001), respectively, when patients were treated with CIP or levofloxacin (LEV) and/or third-generation cephalosporins (CEP). Rates of serious complications were at low levels: peritonitis (2.3%), intestinal hemorrhage (6.8%), and intestinal perforation (1.1%). The present study revealed a long-term clustering trend with respect to PFGE patterns, occasional outbreaks, and the rapid spread of AMP resistance and decreased CIP susceptibility among S. Typhi isolates in recent years.

  2. Applicability of a particularly simple model to nonlinear elasticity of slide-ring gels with movable cross-links as revealed by unequal biaxial deformation.

    Science.gov (United States)

    Kondo, Yuuki; Urayama, Kenji; Kidowaki, Masatoshi; Mayumi, Koichi; Takigawa, Toshikazu; Ito, Kohzo

    2014-10-07

    The strain energy density function (F) of the polyrotaxane-based slide-ring (SR) gels with movable cross-links along the network strands is characterized by unequal biaxial stretching which can achieve various types of deformation. The SR gels as prepared without any post-preparation complication exhibit considerably smaller values of the ratio of the stresses (σy/σx) in the stretched (x) and constrained (y) directions in planar extension than classical chemical gels with heterogeneous and nearly homogeneous network structures do. This feature of the SR gels leads to the peculiar characteristic that the strain energy density function (F) has no explicit cross term of strains in different directions, which is in contrast to F with explicit strain cross terms for most chemical gels and elastomers. The biaxial stress-strain data of the SR gels are successfully described by F of the Gent model with only two parameters (small-strain shear modulus and a parameter representing ultimate elongation), which introduces the finite extensibility effect into the neo-Hookean model with no explicit cross term of strain. The biaxial data of the deswollen SR gels examined in previous study, which underwent a considerable reduction in volume from the preparation state, are also well described by the Gent model, which is in contrast to the case of the classical chemical gels that the stress-strain relations before and after large deswelling are not described by a common type of F due to a significant degree of collapse of the network strands in the deswollen state. These intriguing features of nonlinear elasticity of the SR gels originate from a novel function of the slidable cross-links that can maximize the arrangement entropy of cross-linked and non-cross-linked cyclic molecules in the deformed networks.

  3. Method of electrostatic filtration

    International Nuclear Information System (INIS)

    Devienne, F.M.

    1975-01-01

    Electrostatic filtration of secondary ions of mass m in a given mass ratio with a primary ion of mass M which has formed the secondary ions by fission is carried out by a method which consists in forming a singly-charged primary ion of the substance having a molecular mass M and extracting the ion at a voltage V 1 with respect to ground. The primary ion crosses a potential barrier V 2 , in producing the dissociation of the ion into at least two fragments of secondary ions and in extracting the fragment ion of mass m at a voltage V 2 . Filtration is carried out in an electrostatic analyzer through which only the ions of energy eV'' are permitted to pass, detecting the ions which have been filtered. The mass m of the ions is such that (M/m) = (V 1 - V 2 )/(V'' - V 2 )

  4. Facility of aerosol filtration

    Energy Technology Data Exchange (ETDEWEB)

    Duverger de Cuy, G; Regnier, J

    1975-04-18

    Said invention relates to a facility of aerosol filtration, particularly of sodium aerosols. Said facility is of special interest for fast reactors where sodium fires involve the possibility of high concentrations of sodium aerosols which soon clog up conventional filters. The facility intended for continuous operation, includes at the pre-filtering stage, means for increasing the size of the aerosol particles and separating clustered particles (cyclone separator).

  5. Mixture based outlier filtration

    Czech Academy of Sciences Publication Activity Database

    Pecherková, Pavla; Nagy, Ivan

    2006-01-01

    Roč. 46, č. 2 (2006), s. 30-35 ISSN 1210-2709 R&D Projects: GA MŠk 1M0572; GA MDS 1F43A/003/120 Institutional research plan: CEZ:AV0Z10750506 Keywords : data filtration * system modelling * mixture models Subject RIV: BD - Theory of Information http://library.utia.cas.cz/prace/20060165.pdf

  6. Detergent zeolite filtration plant

    OpenAIRE

    Stanković Mirjana S.; Pezo Lato L.

    2003-01-01

    The IGPC Engineering Department designed basic projects for detergent zeolite filtration plant, using technology developed in the IGPC laboratories. Several projects were completed: technological, machine, electrical, automation. On the basis of these projects, a production plant with a capacity of 75,000 t/y was manufactured, at "Zeolite Mira", Mira (VE), Italy, in 1997, for increasing detergent zeolite production, from 50,000 to 100,000 t/y. The main goal was to increase the detergent zeoli...

  7. Filtration of polydispersed colloids

    International Nuclear Information System (INIS)

    Nuttall, H.E.

    1988-01-01

    In this study, the dynamic microscopic form of the population balance model is applied to the problem of polydispersed particle capture in one spatial diffusion. This mathematical modeling approach can be applied to the difficult and potentially important problem of particulate (radiocolloid) transport in the groundwater surrounding a nuclear waste disposal site. To demonstrate the population balance methodology, the equations were developed and used to investigate transport and capture of polydispersed colloids in packed columns. Modeling simulations were compared to experimental column data. The multidimensional form of the population balance equation was used to analyze the transport and capture of polydispersed colloids. A numerical model was developed to describe transport of polydispersed colloids through a one-dimensional porous region. The effects of various size distributions were investigated in terms of capture efficiency. For simulating the column data, it was found by trial and error that as part of the population balance model a linear size dependent filtration function gave a good fit to the measured colloid concentration profile. The effects of constant versus size dependent filtration coefficients were compared and the differences illustrated by the calculated colloid profile within the column. Also observed from the model calculations was the dramatically changing liquid-phase colloid-size distribution which was plotted as a function of position down the column. This modeling approach was excellent for describing and understanding microscopic filtration in porous media

  8. BWR condensate filtration studies

    International Nuclear Information System (INIS)

    Wilson, J.A.; Pasricha, A.; Rekart, T.E.

    1993-09-01

    Poor removal of particulate corrosion products (especially iron) from condensate is one of the major problems in BWR systems. The presence of activated corrosion products creates ''hot spots'' and increases piping dose rates. Also, fuel efficiency is reduced and the risk of fuel failure is increased by the deposit of corrosion products on the fuel. Because of these concerns, current EPRI guidelines call for a maximum of 2 ppb of iron in the reactor feedwater with a level of 0.5 ppb being especially desirable. It has become clear that conventional deep bed resins are incapable of meeting these levels. While installation of prefilter systems is an option, it would be more economical for plants with naked deep beds to find an improved bead resin for use in existing systems. BWR condensate filtration technologies are being tested on a condensate side stream at Hope Creek Nuclear Generating Station. After two years of testing, hollow fiber filters (HFF) and fiber matrix filters (FMF), and low crosslink cation resin, all provide acceptable results. The results are presented for pressure drop, filtration efficiency, and water quality measurements. The costs are compared for backwashable non-precoat HFF and FMF. Results are also presented for full deep bed vessel tests of the low crosslink cation resin

  9. Magnetic-seeding filtration

    Energy Technology Data Exchange (ETDEWEB)

    DePaoli, D.W.; Tsouris, C. [Oak Ridge National Lab., TN (United States); Yiacoumi, Sotira

    1997-10-01

    Magnetic-seeding filtration is a technology under development for the enhanced removal of magnetic and non-magnetic particulates from liquids. This process involves the addition of a small amount of magnetic seed particles (such as naturally occurring iron oxide) to a waste suspension, followed by treatment with a magnetic filter. Non-magnetic and weakly magnetic particles are made to undergo nonhomogeneous flocculation with the seed particles, forming flocs of high magnetic susceptibility that are readily removed by a conventional high-gradient magnetic filter. This technology is applicable to a wide range of liquid wastes, including groundwater, process waters, and tank supernatants. Magnetic-seeding filtration may be used in several aspects of treatment, such as (1) removal of solids, particularly those in the colloidal size range that are difficult to remove by conventional means; (2) removal of contaminants by precipitation processes; and (3) removal of contaminants by sorption processes. Waste stream characteristics for which the technology may be applicable include (1) particle sizes ranging from relatively coarse (several microns) to colloidal particles, (2) high or low radiation levels, (3) broad-ranging flow rates, (4) low to moderate solids concentration, (5) cases requiring high decontamination factors, and (6) aqueous or non-aqueous liquids. At this point, the technology is at the bench-scale stage of development; laboratory studies and fundamental modeling are currently being employed to determine the capabilities of the process.

  10. Magnetic-seeding filtration

    International Nuclear Information System (INIS)

    DePaoli, D.W.; Tsouris, C.; Yiacoumi, Sotira.

    1997-01-01

    Magnetic-seeding filtration is a technology under development for the enhanced removal of magnetic and non-magnetic particulates from liquids. This process involves the addition of a small amount of magnetic seed particles (such as naturally occurring iron oxide) to a waste suspension, followed by treatment with a magnetic filter. Non-magnetic and weakly magnetic particles are made to undergo nonhomogeneous flocculation with the seed particles, forming flocs of high magnetic susceptibility that are readily removed by a conventional high-gradient magnetic filter. This technology is applicable to a wide range of liquid wastes, including groundwater, process waters, and tank supernatants. Magnetic-seeding filtration may be used in several aspects of treatment, such as (1) removal of solids, particularly those in the colloidal size range that are difficult to remove by conventional means; (2) removal of contaminants by precipitation processes; and (3) removal of contaminants by sorption processes. Waste stream characteristics for which the technology may be applicable include (1) particle sizes ranging from relatively coarse (several microns) to colloidal particles, (2) high or low radiation levels, (3) broad-ranging flow rates, (4) low to moderate solids concentration, (5) cases requiring high decontamination factors, and (6) aqueous or non-aqueous liquids. At this point, the technology is at the bench-scale stage of development; laboratory studies and fundamental modeling are currently being employed to determine the capabilities of the process

  11. Health Benefits of Particle Filtration

    OpenAIRE

    Fisk, William J.

    2013-01-01

    The evidence of health benefits of particle filtration in homes and commercial buildings is reviewed. Prior reviews of papers published before 2000 are summarized. The results of 16 more recent intervention studies are compiled and analyzed. Also reviewed are four studies that modeled health benefits of using filtration to reduce indoor exposures to particles from outdoors. Prior reviews generally concluded that particle filtration is, at best, a source of small improvements in allergy and as...

  12. Two-dimensional gel electrophoresis and FTIR spectroscopy reveal both forms of yeast plasma membrane H(+)-ATPase in activated and basal-level enzyme preparations

    Czech Academy of Sciences Publication Activity Database

    Lapathitis, Georgios; Tanfani, F.; Kotyk, Arnošt; Bertoli, E.

    2001-01-01

    Roč. 505, č. 1 (2001), s. 155-158 ISSN 0014-5793 R&D Projects: GA ČR GA204/98/0474 Keywords : H+-ATPase * plasma membrane * two-dimensional gel electrophoresis Subject RIV: CE - Biochemistry Impact factor: 3.644, year: 2001

  13. Immobilized Filters for Air Filtration

    National Research Council Canada - National Science Library

    Mahle, John J; Zaiee, Saeed

    2002-01-01

    ... (settling performance) and attrition resistance. The fabricated filter samples will be analyzed in order to determine the physical and chemical factors affecting mechanical strength and chemical filtration...

  14. Hot filtration 2

    International Nuclear Information System (INIS)

    Jimenez Rebagliati, Raul; Liberman, S.J.

    1982-01-01

    The magnetic filtration technique allows the removal of suspended magnetic species from a fluid at high flow rate and temperature. It is specially advantageous for water purification in systems such as thermonuclear and thermoelectric plants in which corrosion products must be removed from the heat transport and cooling circuits. Using diluted aqueous suspensions of magnetite, the behaviour of a ball matrix filter was studied as a function of flow rate, temperature and concentration of particles. The retention efficiency shows an exponential decay with fluid's velocity and viscosity in agreement with theory. Within the range of concentration considered, there is no change in the retention with concentration. Design parameters for filters according to plant's needs are obtained from the results of this study. (Author) [es

  15. Air filtration in HVAC systems

    CERN Document Server

    Ginestet, Alain; Tronville, Paolo; Hyttinen, Marko

    2010-01-01

    Air filtration Guidebook will help the designer and user to understand the background and criteria for air filtration, how to select air filters and avoid problems associated with hygienic and other conditions at operation of air filters. The selection of air filters is based on external conditions such as levels of existing pollutants, indoor air quality and energy efficiency requirements.

  16. 40 CFR 141.173 - Filtration.

    Science.gov (United States)

    2010-07-01

    ... PRIMARY DRINKING WATER REGULATIONS Enhanced Filtration and Disinfection-Systems Serving 10,000 or More People § 141.173 Filtration. A public water system subject to the requirements of this subpart that does... treatment, direct filtration, slow sand filtration, or diatomaceous earth filtration. A public water system...

  17. Diesel fuel filtration system

    International Nuclear Information System (INIS)

    Schneider, D.

    1996-01-01

    The American nuclear utility industry is subject to tight regulations on the quality of diesel fuel that is stored at nuclear generating stations. This fuel is required to supply safety-related emergency diesel generators--the backup power systems associated with the safe shutdown of reactors. One important parameter being regulated is the level of particulate contamination in the diesel fuel. Carbon particulate is a natural byproduct of aging diesel fuel. Carbon particulate precipitates from the fuel's hydrocarbons, then remains suspended or settles to the bottom of fuel oil storage tanks. If the carbon particulate is not removed, unacceptable levels of particulate contamination will eventually occur. The oil must be discarded or filtered. Having an outside contractor come to the plant to filter the diesel fuel can be costly and time consuming. Time is an even more critical factor if a nuclear plant is in a Limiting Condition of Operation (LCO) situation. A most effective way to reduce both cost and risk is for a utility to build and install its own diesel fuel filtration system. The cost savings associated with designing, fabricating and operating the system inhouse can be significant, and the value of reducing the risk of reactor shutdown because of uncertified diesel fuel may be even higher. This article describes such a fuel filtering system

  18. Problems of multiphase fluid filtration

    CERN Document Server

    Konovalov, AN

    1994-01-01

    This book deals with a spectrum of problems related to the mathematical modeling of multiphase filtration. Emphasis is placed on an inseparable triad: model - algorithm - computer code. An analysis of new and traditional filtration problems from the point of view of both their numerical implementation and the reproduction of one or another technological characteristics of the processes under consideration is given. The basic principles which underlie the construction of efficient numerical methods taking into account the filtration problems are discussed: non-evolutionary nature, degeneration,

  19. Efficient filtration system for paraffin-catalyst slurry separation

    Directory of Open Access Journals (Sweden)

    Khodagholi Mohammad Ali

    2013-01-01

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

  20. Filtration characteristics in membrane bioreactors

    NARCIS (Netherlands)

    Evenblij, H.

    2006-01-01

    Causes of and remedies for membrane fouling in Membrane Bioreactors for wastewater treatment are only poorly understood and described in scientific literature. A Filtration Characterisation Installation and a measurement protocol were developed with the aim of a) unequivocally determination and

  1. Latest aspects of mechanical filtration

    Directory of Open Access Journals (Sweden)

    Stanislav Koláček

    2013-01-01

    Full Text Available The aim of this study was to describe and unify all knowledge about mechanic filtration. The first part deals with the parameters and properties of filtration. Here some important basic concepts are explained such as pressure gradient, filter life, etc. There’s also a description of convenient filtration technology for coarse and fine materials, such as sand, smoke or soot. The second part primarily focuses on the real use and application of filters for liquid and gaseous media. The differences in construction between different types of filters for filtration of fuels, oils, hydraulic fluids, air and cabin filters are described. The last section is focused mainly on new materials for the production of filters. These materials are ceramic or nanomaterials, which can actually be enriched for example with antibacterial silver or some fungicides.

  2. Health benefits of particle filtration.

    Science.gov (United States)

    Fisk, W J

    2013-10-01

    The evidence of health benefits of particle filtration in homes and commercial buildings is reviewed. Prior reviews of papers published before 2000 are summarized. The results of 16 more recent intervention studies are compiled and analyzed. Also, reviewed are four studies that modeled health benefits of using filtration to reduce indoor exposures to particles from outdoors. Prior reviews generally concluded that particle filtration is, at best, a source of small improvements in allergy and asthma health effects; however, many early studies had weak designs. A majority of recent intervention studies employed strong designs and more of these studies report statistically significant improvements in health symptoms or objective health outcomes, particularly for subjects with allergies or asthma. The percentage improvement in health outcomes is typically modest, for example, 7% to 25%. Delivery of filtered air to the breathing zone of sleeping allergic or asthmatic persons may be more consistently effective in improving health than room air filtration. Notable are two studies that report statistically significant improvements, with filtration, in markers that predict future adverse coronary events. From modeling, the largest potential benefits of indoor particle filtration may be reductions in morbidity and mortality from reducing indoor exposures to particles from outdoor air. Published 2013. This article is a US Government work and is in the public domain in the USA.

  3. Health Benefits of Particle Filtration

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William J.

    2013-10-01

    The evidence of health benefits of particle filtration in homes and commercial buildings is reviewed. Prior reviews of papers published before 2000 are summarized. The results of 16 more recent intervention studies are compiled and analyzed. Also, reviewed are four studies that modeled health benefits of using filtration to reduce indoor exposures to particles from outdoors. Prior reviews generally concluded that particle filtration is, at best, a source of small improvements in allergy and asthma health effects; however, many early studies had weak designs. A majority of recent intervention studies employed strong designs and more of these studies report statistically significant improvements in health symptoms or objective health outcomes, particularly for subjects with allergies or asthma. The percent age improvement in health outcomes is typically modest, for example, 7percent to 25percent. Delivery of filtered air to the breathing zone of sleeping allergic or asthmatic persons may be more consistently effective in improving health than room air filtration. Notable are two studies that report statistically significant improvements, with filtration, in markers that predict future adverse coronary events. From modeling, the largest potential benefits of indoor particle filtration may be reductions in morbidity and mortality from reducing indoor exposures to particles from outdoor air.

  4. Health Benefits of Particle Filtration

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William J.

    2013-10-01

    The evidence of health benefits of particle filtration in homes and commercial buildings is reviewed. Prior reviews of papers published before 2000 are summarized. The results of 16 more recent intervention studies are compiled and analyzed. Also reviewed are four studies that modeled health benefits of using filtration to reduce indoor exposures to particles from outdoors. Prior reviews generally concluded that particle filtration is, at best, a source of small improvements in allergy and asthma health effects; however, many early studies had weak designs. A majority of recent intervention studies employed strong designs and more of these studies report statistically significant improvements in health symptoms or objective health outcomes, particularly for subjects with allergies or asthma. The percentage improvement in health outcomes is typically modest, e.g., 7percent to 25percent. Delivery of filtered air to the breathing zone of sleeping allergic or asthmatic persons may be more consistently effective in improving health than room air filtration. Notable are two studies that report statistically significant improvements, with filtration, in markers that predict future adverse coronary events. From modeling, the largest potential benefits of indoor particle filtration may be reductions in morbidity and mortality from reducing indoor exposures to particles from outdoor air.

  5. Effect of phosphate ion on filtration characteristics of solids generated in simulated high level liquid waste

    International Nuclear Information System (INIS)

    Kondo, Y.

    1998-01-01

    The effect of phosphate ion on the filtration characteristics of solids generated in a high level liquid waste was experimentally examined. Addition of phosphate ion into the simulated HLLW induced the formation of phosphate such as zirconium phosphate and phosphomolybdic acid. The filtration rate of zirconium phosphate abruptly dropped in the midst of filtration because of a gel-cake formation on the filter surface. The denitration of the simulated HLLW contained zirconium phosphate improved the filterability of this gelatinous solid. The filtration rates of denitrated HLLW decreased with increase of the phosphate ion concentration, since the solids formed by denitration had irregular particle size and configuration in the simulated HLLW with phosphate ion. To increase the filtration rate of denitrated HLLW, a solid suspension filtration tester was designed. The solid-suspension accelerated the filtration rate only in the simulated HLLW with more than 1500 ppm phosphate ion concentration. Under this condition, the simple agitation can easily suspend the constituent solids of filter cake in the solution and a much higher filtration rate can be obtained because the filter cake is continuously swept from the filter surface by rotation of propellers. (authors)

  6. A difference gel electrophoresis study on thylakoids isolated from poplar leaves reveals a negative impact of ozone exposure on membrane proteins.

    Science.gov (United States)

    Bohler, Sacha; Sergeant, Kjell; Hoffmann, Lucien; Dizengremel, Pierre; Hausman, Jean-Francois; Renaut, Jenny; Jolivet, Yves

    2011-07-01

    Populus tremula L. x P. alba L. (Populus x canescens (Aiton) Smith), clone INRA 717-1-B4, saplings were subjected to 120 ppb ozone exposure for 28 days. Chloroplasts were isolated, and the membrane proteins, solubilized using the detergent 1,2-diheptanoyl-sn-glycero-3-phosphocholine (DHPC), were analyzed in a difference gel electrophoresis (DiGE) experiment comparing control versus ozone-exposed plants. Extrinsic photosystem (PS) proteins and adenosine triphosphatase (ATPase) subunits were detected to vary in abundance. The general trend was a decrease in abundance, except for ferredoxin-NADP(+) oxidoreductase (FNR), which increased after the first 7 days of exposure. The up-regulation of FNR would increase NAPDH production for reducing power and detoxification inside and outside of the chloroplast. Later on, FNR and a number of PS and ATPase subunits decrease in abundance. This could be the result of oxidative processes on chloroplast proteins but could also be a way to down-regulate photochemical reactions in response to an inhibition in Calvin cycle activity.

  7. Filtration and compression of organic materials

    DEFF Research Database (Denmark)

    Christensen, Morten Lykkegaard; Keiding, Kristian

    is to use more simple systems. Dextran-MnO2 particles and polystyrene particles with a water-swollen polyacrylic acid shell have therefore been synthesised. These particles have been filtered and used to study the non-linear filtration behaviour. The compressibility of the formed cake has been investigated......The conventional filtration theory has been based on filtrations of incompressible particles such as anatase, kaolin and clay. The filtration models have later been used for organic slurries but can often not explain the observed experimental data. At constant pressure, the filtrate volume does...... and the discrepancy between the filtration theory and the observed filtration behaviour explained as a time-dependent collapse of the formed cake (creep). Thus, the creep phenomenon has been adopted in the conventional filtration models and it will be shown that the model can be used to simulate filtration data...

  8. Combination of multilocus sequence typing and pulsed-field gel electrophoresis reveals an association of molecular clonality with the emergence of extensive-drug resistance (XDR) in Salmonella.

    Science.gov (United States)

    Cao, Yongzhong; Shen, Yongxiu; Cheng, Lingling; Zhang, Xiaorong; Wang, Chao; Wang, Yan; Zhou, Xiaohui; Chao, Guoxiang; Wu, Yantao

    2018-03-01

    Salmonellae is one of the most important foodborne pathogens and becomes resistant to multiple antibiotics, which represents a significant challenge to food industry and public health. However, a molecular signature that can be used to distinguish antimicrobial resistance profile, particularly multi-drug resistance or extensive-drug resistance (XDR). In the current study, 168 isolates from the chicken and pork production chains and ill chickens were characterized by serotyping, antimicrobial susceptibility test, multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). The results showed that these isolates belonged to 13 serotypes, 14 multilocus sequence types (STs), 94 PFGE genotypes, and 70 antimicrobial resistant profiles. S. Enteritidis, S. Indiana, and S. Derby were the predominant serotypes, corresponding to the ST11, ST17, and ST40 clones, respectively and the PFGE Cluster A, Cluster E, and Cluster D, respectively. Among the ST11-S. Enteritidis (Cluster A) and the ST40-S. Derby (Cluster D) clones, the majority of isolates were resistant to 4-8 antimicrobial agents, whereas in the ST17S. Indiana (Cluster E) clone, isolates showed extensive-drug resistance (XDR) to 9-16 antimicrobial agents. The bla TEM-1-like gene was prevalent in the ST11 and ST17 clones corresponding to high ampicillin resistance. The bla TEM-1-like , bla CTX-M , bla OXA-1-like , sul1, aaC4, aac(6')-1b, dfrA17, and floR gene complex was highly prevalent among isolates of ST17, corresponding to an XDR phenotype. These results demonstrated the association of the resistant phenotypes and genotypes with ST clone and PFGE cluster. Our results also indicated that the newly identified gene complex comprising bla TEM-1-like , bla CTX-M , bla OXA-1-like , sul1, aaC4, aac(6')-1b, dfrA17, and floR, was responsible for the emergence of the ST17S. Indiana XDR clone. ST17 could be potentially used as a molecular signature to distinguish S. Indiana XDR clone. Copyright © 2017

  9. Renal filtration function in patients with gout

    Directory of Open Access Journals (Sweden)

    N. N. Kushnarenko

    2016-01-01

    Full Text Available Aim. To study circadian blood pressure (BP profile in patients with gout depending on the presence of arterial hypertension (HT and their relationship to the renal filtration function.Material and methods. Patients with gout (n=87 were included into the study. All the patients underwent ambulatory BP monitoring (ABPM with the assessment of circadian BP profile, determination of uric acid serum levels, glomerular filtration rate (GFR was evaluated by CKD-EPI method. Depending on GFR level, all the patients were divided into 2 groups - with renal dysfunction or without one.Results. ABPM revealed circadian BP dysregulation in 55% of gout patients both with HT and without HT. Chronic kidney disease (CKD was revealed in 72.4% of male patients, with the prevalence in patients with HT (76.6 vs 61%; p<0.001. Correlations between uric acid levels and some ABPM indicators and GFR were determined.Conclusion. Obtained data suggest the contribution of hyperuricemia in disorders of systemic and renal hemodynamics, leading to the early development of CKD.

  10. Optimization of suspensions filtration with compressible cake

    Directory of Open Access Journals (Sweden)

    Janacova Dagmar

    2016-01-01

    Full Text Available In this paper there is described filtering process for separating reaction mixture after enzymatic hydrolysis to process the chromium tanning waste. Filtration of this mixture is very complicated because it is case of mixture filtration with compressible cake. Successful process strongly depends on mathematical describing of filtration, calculating optimal values of pressure difference, specific resistant of filtration cake and temperature maintenance which is connected with viscosity change. The mathematic model of filtration with compressible cake we verified in laboratory conditions on special filtration device developed on our department.

  11. Filtration set for gaseous fluids

    International Nuclear Information System (INIS)

    Lebrun, B.; Couvrat-Desvergnes, A.

    1988-01-01

    This filtration set is made by a cylindrical vessel containing upstairs to downstairs, the gas inlet, a sealed floor for man inspection, a horizontal granular filter bed, a linen with a porosity inferior to the granulometry of the filter bed, a light support layer of material of larger granulometry, gas permeable tubes and an annular collector connecting the tubes to the outlet [fr

  12. Some observations on air filtration

    NARCIS (Netherlands)

    Kluyver, A.J.; Visser, J.

    1950-01-01

    1. A method has been developed for testing the filtration efficiency of some filter materials. For each of the materials investigated — cotton wool, stillite and carbon — a suitable filter has been devised. 2. The filtered air was analyzed as to its germ content with the aid of a set of 3 capillary

  13. Filtration device for active effluents

    International Nuclear Information System (INIS)

    Guerin, M.; Meunier, G.

    1994-01-01

    Among the various techniques relating to solid/liquid separations, filtration is currently utilized for treating radioactive effluents. After testing different equipments on various simulated effluents, the Valduc Center has decided to substitute a monoplate filter for a rotative diatomite precoated filter

  14. Microalgae fractionation using steam explosion, dynamic and tangential cross-flow membrane filtration.

    Science.gov (United States)

    Lorente, E; Hapońska, M; Clavero, E; Torras, C; Salvadó, J

    2017-08-01

    In this study, the microalga Nannochloropsis gaditana was subjected to acid catalysed steam explosion treatment and the resulting exploded material was subsequently fractionated to separate the different fractions (lipids, sugars and solids). Conventional and vibrational membrane setups were used with several polymeric commercial membranes. Two different routes were followed: 1) filtration+lipid solvent extraction and 2) lipid solvent extraction+filtration. Route 1 revealed to be much better since the used membrane for filtration was able to permeate the sugar aqueous phase and retained the fraction containing lipids; after this, an extraction required a much lower amount of solvent and a better recovering yield. Filtration allowed complete lipid rejection. Dynamic filtration improved permeability compared to the tangential cross-flow filtration. Best membrane performance was achieved using a 5000Da membrane with the dynamic system, obtaining a permeability of 6L/h/m 2 /bar. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Filtrations of free groups as intersections

    OpenAIRE

    Efrat, Ido

    2013-01-01

    For several natural filtrations of a free group S we express the n-th term of the filtration as the intersection of all kernels of homomorphisms from S to certain groups of upper-triangular unipotent matrices. This generalizes a classical result of Grun for the lower central filtration. In particular, we do this for the n-th term in the lower p-central filtration of S.

  16. Portable field water sample filtration unit

    International Nuclear Information System (INIS)

    Hebert, A.J.; Young, G.G.

    1977-01-01

    A lightweight back-packable field-tested filtration unit is described. The unit is easily cleaned without cross contamination at the part-per-billion level and allows rapid filtration of boiling hot and sometimes muddy water. The filtration results in samples that are free of bacteria and particulates and which resist algae growth even after storage for months. 3 figures

  17. Sol-gel applications for ceramic membrane preparation

    Science.gov (United States)

    Erdem, I.

    2017-02-01

    Ceramic membranes possessing superior properties compared to polymeric membranes are more durable under severe working conditions and therefore their service life is longer. The ceramic membranes are composed of some layers. The support is the layer composed of coarser ceramic structure and responsible for mechanical durability under filtration pressure and it is prepared by consolidation of ceramic powders. The top layer is composed of a finer ceramic micro-structure mainly responsible for the separation of components present in the fluid to be filtered and sol-gel method is a versatile tool to prepare such a tailor-made ceramic filtration structure with finer pores. Depending on the type of filtration (e.g. micro-filtration, ultra-filtration, nano-filtration) aiming separation of components with different sizes, sols with different particulate sizes should be prepared and consolidated with varying precursors and preparation conditions. The coating of sol on the support layer and heat treatment application to have a stable ceramic micro-structure are also important steps determining the final properties of the top layer. Sol-gel method with various controllable parameters (e.g. precursor type, sol formation kinetics, heat treatment conditions) is a practical tool for the preparation of top layers of ceramic composite membranes with desired physicochemical properties.

  18. Demonstration of creep during filtration

    DEFF Research Database (Denmark)

    Christensen, Morten Lykkegaard; Bugge, Thomas Vistisen; Kirchheiner, Anders Løvenbalk

    The classical filtration theory assumes a unique relationship between the local filter cake porosity and the local effective pressure. For a number of compressible materials, it has however been observed that during the consolidation stage this may not be the case. It has been found...... that the production of filtrate also depends on the characteristic time for the filter cake solids to deform. This is formulated in the Terzaghi-Voigt model in which a secondary consolidation is introduced. The secondary consolidation may be visualized by plots of the relative cake deformation (U) v.s. the square...... root of time. Even more clearly it is demonstrated by plotting the liquid pressure at the cake piston interface v.s. the relative deformation (to be shown). The phenomenon of a secondary consolidation processes is in short called creep. Provided that the secondary consolidation rate is of the same...

  19. Properties of plastic filtration material

    Energy Technology Data Exchange (ETDEWEB)

    Paluch, W.

    1988-01-01

    Discusses properties of filters made of thermoplastic granulated material. The granulated plastic has a specific density of 10.3-10.6 kN/m/sup 3/ and a bulk density of about 6 kN/m/sup 3/. Its chemical resistance to acids, bases and salts is high but is it soluble in organic solvents. Filters made of this material are characterized by a porosity coefficient of 36.5% and a bulk density of 5.7-6.8 kN/m/sup 3/. Physical and mechanical properties of filter samples made of thermoplastic granulated material (50x50x50 mm) were investigated under laboratory conditions. Compression strength and influencing factors were analyzed (ambient temperature, manufacturing technology). Tests show that this filtration material developed by Poltegor is superior to other filtration materials used in Poland.

  20. Preferential Interactions between ApoE-containing Lipoproteins and Aβ Revealed by a Detection Method that Combines Size Exclusion Chromatography with Non-Reducing Gel-shift

    Science.gov (United States)

    LaDu, Mary Jo; Munson, Gregory W.; Jungbauer, Lisa; Getz, Godfrey S.; Reardon, Catherine A.; Tai, Leon M.; Yu, Chunjiang

    2012-01-01

    The association between apolipoprotein E (apoE) and amyloid-β peptide (Aβ) may significantly impact the function of both proteins, thus affecting the etiology of Alzheimer’s disease (AD). However, apoE/Aβ interactions remain fundamentally defined by the stringency of the detection method. Here we use size exclusion chromatography (SEC) as a non-stringent approach to the detection of apoE/Aβ interactions in solution, specifically apoE and both endogenous and exogenous Aβ from plasma, CSF and astrocyte conditioned media. By SEC analysis, Aβ association with plasma and CNS lipoproteins is apoE-dependent. While endogenous Aβ elutes to specific human plasma lipoproteins distinct from those containing apoE, it is the apoE-containing lipoproteins that absorb excess amounts of exogenous Aβ40. In human CSF, apoE, endogenous Aβ and phospholipid elute in an almost identical profile, as do apoE, exogenous Aβ and phospholipid from astrocyte conditioned media. Combining SEC fractionation with subsequent analysis for SDS-stable apoE/Aβ complex reveals that apoE-containing astrocyte lipoproteins exhibit the most robust interactions with Aβ. Thus, standardization of the methods for detecting apoE/Aβ complex is necessary to determine its functional significance in the neuropathology characteristic of AD. Importantly, a systematic understanding of the role of apoE-containing plasma and CNS lipoproteins in Aβ homeostasis could potentially contribute to identifying a plasma biomarker currently over-looked because it has multiple components. PMID:22138302

  1. Corrosion-product filtration in PWRs: Topical report

    International Nuclear Information System (INIS)

    Balakrishnan, P.V.; Buckley, L.P.

    1988-04-01

    As part of a programme on the optimization of pressurized water reactor (PWR) secondary side water treatment, laboratory-scale studies on filtration of the feedwater using materials having chemically active adsorbing surfaces were carried out. Graphite, zirconia and titania were identified, from a review of existing literature, as suitable filtration media, the last two because of their ion-exchange capability. The efficiency of filters packed with granular graphite for filtration of simulated feed train corrosion products and the pressure drop across the filters were determined as functions of filter dimensions and operating parameters at room temperature. A rough sizing of a full-flow feedwater filter using granular graphite was done on the basis of observations from the room temperature tests. Further studies are suggested at low concentrations of the corrosion product and at high temperature typical of steam generator feedwater after the high pressure heaters to derive realistic design parameters for a filter for installation in the PWR secondary circuit. Zirconia was produced in the form of spherical particles using a sol-gel process. The zirconia behaved as an anion exchanger at low pH and as a cation exchanger at high pH. Its suitability for purification of water at high temperature should be determined by futher studies. 30 refs., 16 figs., 8 tabs

  2. Filtration behavior of organic substance through a compacted bentonite

    International Nuclear Information System (INIS)

    Kanaji, Mariko; Kuno, Yoshio; Yui, Mikazu

    1999-07-01

    Filtration behavior of organic substance through a compacted bentonite was investigated. Na-type bentonite containing 30wt% of quartz sand was compacted in a column and the dry density was adjusted to be 1.6 g/cm 3 . Polyacrylic acid solution (including three types of polyacrylic acid, average molecular weight 2,100, 15,000 and 450,000) was prepared and was passed through the compacted bentonite. Molecular weight distributions of polyacrylic acid in the effluent solution were analysed by GPC (Gel Permeation Chromatography). A batch type experiment was also carried out in order to examine a sorption behavior of these organic substances onto the surfaces of grains of the bentonite. The results indicated that the smaller size polyacrylic acid (molecular weight < 100,000) was passed through the compacted bentonite. On the other hand, the larger size polyacrylic acid (molecular weight ≥100,000) was mostly filtrated by the compacted bentonite. The batch type sorption tests clarified that the polyacrylic acid did not sorb onto the surfaces of minerals constituting the bentonite. Therefore it was suggested that the larger size molecules (≥100,000) of organic substances could be predominantly filtrated by the microstructure of the compacted bentonite. (author)

  3. Relation Between Filtration and Soil Consolidation Theories

    Directory of Open Access Journals (Sweden)

    Strzelecki Tomasz

    2015-03-01

    Full Text Available This paper presents a different, than commonly used, form of equations describing the filtration of a viscous compressible fluid through a porous medium in isothermal conditions. This mathematical model is compared with the liquid flow equations used in the theory of consolidation. It is shown that the current commonly used filtration model representation significantly differs from the filtration process representation in Biot’s and Terzaghi’s soil consolidation models, which has a bearing on the use of the methods of determining the filtration coefficient on the basis of oedometer test results. The present analysis of the filtration theory equations should help interpret effective parameters of the non-steady filtration model. Moreover, equations for the flow of a gas through a porous medium and an interpretation of the filtration model effective parameters in this case are presented.

  4. Water filtration using plant xylem.

    Directory of Open Access Journals (Sweden)

    Michael S H Boutilier

    Full Text Available Effective point-of-use devices for providing safe drinking water are urgently needed to reduce the global burden of waterborne disease. Here we show that plant xylem from the sapwood of coniferous trees--a readily available, inexpensive, biodegradable, and disposable material--can remove bacteria from water by simple pressure-driven filtration. Approximately 3 cm(3 of sapwood can filter water at the rate of several liters per day, sufficient to meet the clean drinking water needs of one person. The results demonstrate the potential of plant xylem to address the need for pathogen-free drinking water in developing countries and resource-limited settings.

  5. Side Stream Filtration for Cooling Towers

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-10-20

    This technology evaluation assesses side stream filtration options for cooling towers, with an objective to assess key attributes that optimize energy and water savings along with providing information on specific technology and implementation options. This information can be used to assist Federal sites to determine which options may be most appropriate for their applications. This evaluation provides an overview of the characterization of side stream filtration technology, describes typical applications, and details specific types of filtration technology.

  6. Relation Between Filtration and Soil Consolidation Theories

    OpenAIRE

    Strzelecki Tomasz; Strzelecki Michał

    2015-01-01

    This paper presents a different, than commonly used, form of equations describing the filtration of a viscous compressible fluid through a porous medium in isothermal conditions. This mathematical model is compared with the liquid flow equations used in the theory of consolidation. It is shown that the current commonly used filtration model representation significantly differs from the filtration process representation in Biot’s and Terzaghi’s soil consolidation models, which has a bearing on...

  7. Filtration of Sludge and Sodium Nonatitanate Solutions

    International Nuclear Information System (INIS)

    Poirier, M.R.

    2000-01-01

    The proposed facility designs for the ion exchange and solvent extraction flowsheets under development to treat high level waste at the Savannah River Site use crossflow filtration to remove entrained sludge and monosodium titanate (MST). Bench-scale and pilot-scale testing performed with simulated feed streams showed much lower filtration rates than desired for the process. This report documents an investigation of the impact on filtration of using Honeywell sodium nonatitanate (ST), rather than MST, for strontium and actinide removal

  8. Cake creep during filtration of flocculated manure

    DEFF Research Database (Denmark)

    Christensen, Morten Lykkegaard; Keiding, Kristian

    is filtered. Hence, it is not possible to scale up the experiments, and it is therefore difficult to optimize the flocculation and estimate the needed filter media area. Similar problems have been observed when sewage sludge and synthetic core-shell colloids are filtered, and it has been suggested......, and the mixing procedure affect the result, and lab-scale experiments are often used to study how these pre-treatments influence the filtration process. However, the existing mathematical filtration models are based on filtration of inorganic particles and cannot simulate the filtration data obtained when manure...

  9. Filtration Behaviour and Fouling Mechanisms of Polysaccharides

    Directory of Open Access Journals (Sweden)

    Sondus Jamal

    2014-07-01

    Full Text Available This study investigated filtration behaviors of polysaccharides solutions, both alone and in mixture with proteins, in the short-time constant flux filtration with the focus on factors affecting the transmembrane pressure (TMP increase rate, the irreversible filtration resistance, and the membrane rejection behavior. The results showed that the TMP increase rates in the short-time constant flux filtration of alginate solutions were significantly affected by the calcium addition, alginate concentration, and flux. Although the addition of calcium resulted in a decrease in the TMP increase rate, it was found that the irreversible fouling developed during the filtration increased with the calcium addition, implying that the double-sided effect of calcium on membrane filtration and that the TMP increase rate observed in the filtration does not always reflect the irreversible membrane fouling development. It was also found that for the filtration of solutions containing mixed alginate and BSA, alginate exerted a dominant effect on the TMP increase rate and the membrane exhibited a reduced rejection to both alginate and BSA molecules compared to that in the filtration of the pure alginate or BSA.

  10. Initial investigation of a novel light-scattering gel phantom for evaluation of optical CT scanners for radiotherapy gel dosimetry

    International Nuclear Information System (INIS)

    Bosi, Stephen; Naseri, Pourandokht; Puran, Alicia; Davies, Justin; Baldock, Clive

    2007-01-01

    There is a need for stable gel materials for phantoms used to validate optical computerized tomography (CT) scanners used in conjunction with radiation-induced polymerizing gel dosimeters. Phantoms based on addition of light-absorbing dyes to gelatine to simulate gel dosimeters have been employed. However, to more accurately simulate polymerizing gels one requires phantoms that employ light-scattering colloidal suspensions added to the gel. In this paper, we present the initial results of using an optical CT scanner to evaluate a novel phantom in which radiation-exposed polymer gels are simulated by the addition of colloidal suspensions of varying turbidity. The phantom may be useful as a calibration transfer standard for polymer gel dosimeters. The tests reveal some phenomena peculiar to light-scattering gels that need to be taken into account when calibrating polymer gel dosimeters

  11. Removing water from gels

    International Nuclear Information System (INIS)

    Lane, E.S.; Winter, J.A.

    1982-01-01

    Water is removed from a gel material by contacting the gel material with an organic liquid and contacting the organic liquid with a gas such that water is taken up by the gas. The invention, in one embodiment, may be used to dry gel materials whilst maintaining an open porous network therein. In one example, the invention is applied to gel precipitated spheres containing uranium and plutonium. (author)

  12. Filtration and retention capacities of filter aids

    International Nuclear Information System (INIS)

    Mellah, A.; Boualia, A.

    1992-01-01

    The present work involves the filtration of impure uranyl nitrate solutions by different filter aids such as kieselguhr, celite and bleaching clay. The retention of substances contained in uranyl nitrate solution was determined using the three filter aids. A study of the effects of granulometry and filter earths treatment (thermal and chemical) on the filtration rate was performed

  13. 40 CFR 141.73 - Filtration.

    Science.gov (United States)

    2010-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Filtration and Disinfection § 141.73 Filtration. A public water system that uses a surface water source or a ground water source under the direct influence of surface water...

  14. Polymer gels and networks

    National Research Council Canada - National Science Library

    Osada, Yoshihito; Khokhlov, A. R

    2002-01-01

    ... or magnetic field, etc.). It was realized that not only can polymer gels absorb and hold a considerable volume of liquids, but they can also be forced to expel the absorbed liquid in a controlled manner. Of particular interest are hydrogels, i.e., polymer gels, which swell extensively in water. The most common hydrogels are polyelectrolyte gels: ...

  15. Identification and characterization of a 29-kilodalton protein from Mycobacterium tuberculosis culture filtrate recognized by mouse memory effector cells

    DEFF Research Database (Denmark)

    Rosenkrands, I; Rasmussen, P.B.; Carnio, M

    1998-01-01

    Culture filtrate proteins from Mycobacterium tuberculosis induce protective immunity in various animal models of tuberculosis. Two molecular mass regions (6 to 10 kDa and 24 to 36 kDa) of short-term culture filtrate are preferentially recognized by Th1 cells in animal models as well as by patients...... the antigen 85 complex was selected. The 29-kDa antigen (CFP29) was purified from M. tuberculosis short-term culture filtrate by thiophilic adsorption chromatography, anion-exchange chromatography, and gel filtration, In its native form, CFP29 forms a polymer with a high molecular mass. CFP29 was mapped......, and they both elicited the release of high levels of gamma interferon from mouse memory effector cells isolated during the recall of protective immunity to tuberculosis. Interspecies analysis by immunoblotting and PCR demonstrated that CFP29 is widely distributed in mycobacterial species....

  16. Colloid molecular weight estimation by gel chromatography/acrylamide gel electrophoresis

    International Nuclear Information System (INIS)

    Liberatore, F.A.; Dearborn, C.; Nigam, S.; Poon, C.; Camin, L.; Liteplo, M.

    1984-01-01

    Size or molecular weight (MW) estimation of radiolabeled collides in aqueous solutions has long been a problem. The authors have prepared several minimicroaggregated albumin colloids (mμAA) by heat denaturation of stannous-containing HSA solutions at pH 7.0, 7.5, and 8.5). The resulting colloids were labeled with Tc-99m and compared with Au-198 colloid and Tc-99m-antimony sulfide colloid (Tc-99m-Sb/sub 2/S3) by gel chromatography and gel electrophoresis. Tc-99mm-mμAA aggregated at pH 7.0 and the Au-198 colloid appeared in the external void volume of a BioRad A5.0 agarose column indicating an apparent MW of > 5 x 10/sup 6/ daltons. The pH7.5 Tc-99m-mμAA, migrated within the filtration range of the column as did a small fraction of Tc-99m-Sb/sub 2/S/sub 3/, suggesting that the MW is between 6 x 10/sup 4/ - 5 x 10/sup 6/ daltons. The Tc-99m-mμAA, aggregated at pH 8.5, had an apparent MW on gel filtration similar to that of untreated albumin, MW 6.6 x 10-/sup 4/ daltons. The mobilities of the colloids, on acrylamide disc gel electrophoresis, were consistent with the results on gel chromatography. The largest colloids, Au-198 colloid and pH 7.0 Tc-99m-mμAA, barely entered the separating gel; intermediate sized colloids, a small fraction of Tc-99m-Sb/sub 2/S/sub 3/ and pH 7.5 Tc-99m-mμAA migrated farther into the separating gel; while pH 8.5 Tc-99m-mμAA had mobility approaching that of untreated albumin. Lymphoscintigraphy studies using these colloids in animals showed the predicted, particle size-related differences in migration and clearance. The authors conclude that gel chromatography and gel electrophoresis are useful methods for estimating the apparent size of the colloidal particles

  17. Application of phase diagrams to obtain a new surfactant-based fracturing gel; Aplicacao de diagrama de fases para obtencao de um novo gel de fraturamento hidraulico

    Energy Technology Data Exchange (ETDEWEB)

    Dantas, Tereza N. de Castro; Santana, Vanessa C.; Dantas Neto, Afonso A.; Franca Neta, Luzia S. de; Albuquerque, Heraldo S. [Rio Grande do Norte Univ., Natal, RN (Brazil)]. E-mail: tereza@eq.ufrn.br

    2003-07-01

    Through pseudo ternary phases diagram was defined a gel area with the objective of obtaining a new surfactant-based fracturing gel. The surfactant used was synthesized from regional vegetable oil. Fracturing gel properties, like: viscosity, leak off coefficient and proppant-settling rate were analyzed. The obtained results with the surfactant-based gel had its properties compared with a HPG-based gel (hydroxypropyl guar). Rheological tests was accomplished at 100 s{sup -1} being varied the temperature from 26 to 86 deg C, where the surfactant-based gel showed great results. The leak off coefficient was determined by static filtration and the new gel presented smaller coefficient in relation to the HPG gel. The proppant-setting rate was also determined in the gel and, the surfactant-based gel showed good static proppant support. One can conclude that obtained gel presents compatible characteristics when compared with the HPG gel, without the inconvenience of leaving insoluble residues in the well. (author)

  18. Particle filtration in consolidated granular systems

    International Nuclear Information System (INIS)

    Schwartz, L.M.; Wilkinson, D.J.; Bolsterli, M.; Hammond, P.

    1993-01-01

    Grain-packing algorithms are used to model the mechanical trapping of dilute suspensions of particles by consolidated granular media. We study the distribution of filtrate particles, the formation of a damage zone (internal filter cake), and the transport properties of the host--filter-cake composite. At the early stages of filtration, our simulations suggest simple relationships between the structure of the internal filter cake and the characteristics of the underlying host matrix. These relationships are then used to describe the dynamics of the filtration process. Depending on the grain size and porosity of the host matrix, calculated filtration rates may either be greater than (spurt loss) or less than (due to internal clogging) those predicted by standard surface-filtration models

  19. The performance of gel technetium-99m generator

    International Nuclear Information System (INIS)

    Liu Yishu

    2004-01-01

    Technetium-99m, as one of the important radionuclides in nuclear medical science, has been widely used for diseases diagnosis in both developed and developing countries for many years. Technetium-99m can be obtained from both fission-type and gel-type Tc-99m generator. Fission-type generator was prepared by Molybdenum-99 separated from fission products of uranium-235 and gel-type was prepared by irradiating nature MoO 3 in reactor, and a series of chemical and physical processes. This paper briefly describes the manufacturing technical process of gel-type Technetium-99 generator, including the preparation of target containing nature MoO 3 , the target irradiation in reactor, gel preparation, gel filtration and drying, dried gel cracking, generator loading and activity calibration of generator. The performances of gel-type Technetium-99m generator, such as elution efficiency, elution profile, the pH, Mo breakthrough, Zirconium content, radiochemical purity, radionuclidic purity, sterility and pyrogencity of eluate, are also expatiated in detail. Comparing with fission-type Technetium-99m generator, the defects of gel-type Technetium-99m generator are enumerated and their overcoming solutions are recommended in this paper. (author)

  20. Radio elements / bottom salts separation by nano-filtration aided by complexation in a highly saline environment

    International Nuclear Information System (INIS)

    Gaubert, Eric

    1997-01-01

    This research thesis addresses the use of a membrane-based technique, nano-filtration, aided or not by complexation, for the processing of highly saline liquid effluents produced by radio-chemical decontamination. The objective is to separate non-radioactive elements (sodium nitrate) from radio-elements (caesium, strontium and actinides) in order to reduce the volume of wastes. Within the perspective of an industrial application, a system to concentrate the effluent is firstly defined. Different nano-filtration membranes are tested and reveal to be insufficient in highly saline environment. A stage of selective complexation of radio-elements is therefore considered before nano-filtration. The main factors affecting performance of nano-filtration-complexation (for a given membrane system) are identified: ionic force, pH, ligand content, trans-membrane pressure. Finally, a nano-filtration pilot is implemented to perform nano-filtration-complexation operations by remote handling on radioactive substances [fr

  1. Applications of gel dosimetry

    International Nuclear Information System (INIS)

    Ibbott, Geoffrey S

    2004-01-01

    Gel dosimetry has been examined as a clinical dosimeter since the 1950s. During the last two decades, however, a rapid increase in the number of investigators has been seen, and the body of knowledge regarding gel dosimetry has expanded considerably. Gel dosimetry is still considered a research project, and the introduction of this tool into clinical use is proceeding slowly. This paper will review the characteristics of gel dosimetry that make it desirable for clinical use, the postulated and demonstrated applications of gel dosimetry, and some complications, set-backs, and failures that have contributed to the slow introduction into routine clinical use

  2. Transport Phenomena in Gel

    Directory of Open Access Journals (Sweden)

    Masayuki Tokita

    2016-05-01

    Full Text Available Gel becomes an important class of soft materials since it can be seen in a wide variety of the chemical and the biological systems. The unique properties of gel arise from the structure, namely, the three-dimensional polymer network that is swollen by a huge amount of solvent. Despite the small volume fraction of the polymer network, which is usually only a few percent or less, gel shows the typical properties that belong to solids such as the elasticity. Gel is, therefore, regarded as a dilute solid because its elasticity is much smaller than that of typical solids. Because of the diluted structure, small molecules can pass along the open space of the polymer network. In addition to the viscous resistance of gel fluid, however, the substance experiences resistance due to the polymer network of gel during the transport process. It is, therefore, of importance to study the diffusion of the small molecules in gel as well as the flow of gel fluid itself through the polymer network of gel. It may be natural to assume that the effects of the resistance due to the polymer network of gel depends strongly on the network structure. Therefore, detailed study on the transport processes in and through gel may open a new insight into the relationship between the structure and the transport properties of gel. The two typical transport processes in and through gel, that is, the diffusion of small molecules due to the thermal fluctuations and the flow of gel fluid that is caused by the mechanical pressure gradient will be reviewed.

  3. Formation of siliceous sediments in brandy after diatomite filtration.

    Science.gov (United States)

    Gómez, J; Gil, M L A; de la Rosa-Fox, N; Alguacil, M

    2015-03-01

    Brandy is quite a stable spirit but sometimes light sediment appears. This sediment was separated and analysed by IR and SEM-EDX. It was revealed that the sediment is composed mostly of silica and residual organic matter. Silica was present as an amorphous phase and as microparticles. In an attempt to reproduce the formation of the sediment, a diatomite extract was prepared with an ethanol/water mixture (36% vol.) and a calcined diatomite similar to that used in brandy filtration. This extract was added to unfiltered brandy in different amounts. After 1 month, the Si concentration decreased in all samples and sediments with similar compositions and features to those found in the unstable brandy appeared. The amounts of sediment obtained were directly related to the decrease in Si concentration in solution. Consequently, it can be concluded that siliceous sediment in brandy originates from Si released during diatomite filtration. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Dynamic Heterogeneous Multiscale Filtration Model: Probing Micro- and Macroscopic Filtration Characteristics of Gasoline Particulate Filters.

    Science.gov (United States)

    Gong, Jian; Viswanathan, Sandeep; Rothamer, David A; Foster, David E; Rutland, Christopher J

    2017-10-03

    Motivated by high filtration efficiency (mass- and number-based) and low pressure drop requirements for gasoline particulate filters (GPFs), a previously developed heterogeneous multiscale filtration (HMF) model is extended to simulate dynamic filtration characteristics of GPFs. This dynamic HMF model is based on a probability density function (PDF) description of the pore size distribution and classical filtration theory. The microstructure of the porous substrate in a GPF is resolved and included in the model. Fundamental particulate filtration experiments were conducted using an exhaust filtration analysis (EFA) system for model validation. The particulate in the filtration experiments was sampled from a spark-ignition direct-injection (SIDI) gasoline engine. With the dynamic HMF model, evolution of the microscopic characteristics of the substrate (pore size distribution, porosity, permeability, and deposited particulate inside the porous substrate) during filtration can be probed. Also, predicted macroscopic filtration characteristics including particle number concentration and normalized pressure drop show good agreement with the experimental data. The resulting dynamic HMF model can be used to study the dynamic particulate filtration process in GPFs with distinct microstructures, serving as a powerful tool for GPF design and optimization.

  5. Sol-Gel Glasses

    Science.gov (United States)

    Mukherjee, S. P.

    1985-01-01

    Multicomponent homogeneous, ultrapure noncrystalline gels/gel derived glasses are promising batch materials for the containerless glass melting experiments in microgravity. Hence, ultrapure, homogeneous gel precursors could be used to: (1) investigate the effect of the container induced nucleation on the glass forming ability of marginally glass forming compositions; and (2) investigate the influence of gravity on the phase separation and coarsening behavior of gel derived glasses in the liquid-liquid immiscibility zone of the nonsilicate systems having a high density phase. The structure and crystallization behavior of gels in the SiO2-GeO2 as a function of gel chemistry and thermal treatment were investigated. As are the chemical principles involved in the distribution of a second network former in silica gel matrix being investigated. The procedures for synthesizing noncrystalline gels/gel-monoliths in the SiO2-GeO2, GeO2-PbO systems were developed. Preliminary investigations on the levitation and thermal treatment of germania silicate gel-monoliths in the Pressure Facility Acoustic Levitator were done.

  6. Quantitative comparison between the gel-film and polyvinyl alcohol methods for dehydrogenase histochemistry reveals different intercellular distribution patterns of glucose-6-phosphate and lactate dehydrogenases in mouse liver

    NARCIS (Netherlands)

    Griffini, P.; Vigorelli, E.; Bertone, V.; Freitas, I.; van Noorden, C. J.

    1994-01-01

    The precise histochemical localization and quantification of the activity of soluble dehydrogenases in unfixed cryostat sections requires the use of tissue protectants. In this study, two protectants, polyvinyl alcohol (PVA) and agarose gel, were compared for assaying the activity of lactate

  7. Projective Dimension in Filtrated K-Theory

    DEFF Research Database (Denmark)

    Bentmann, Rasmus Moritz

    2013-01-01

    Under mild assumptions, we characterise modules with projective resolutions of length n∈N in the target category of filtrated K-theory over a finite topological space in terms of two conditions involving certain Tor -groups. We show that the filtrated K-theory of any separable C∗dash-algebra over...... any topological space with at most four points has projective dimension 2 or less. We observe that this implies a universal coefficient theorem for rational equivariant KK-theory over these spaces. As a contrasting example, we find a separable C∗dash-algebra in the bootstrap class over a certain five......-point space, the filtrated K-theory of which has projective dimension 3. Finally, as an application of our investigations, we exhibit Cuntz-Krieger algebras which have projective dimension 2 in filtrated K-theory over their respective primitive spectrum....

  8. Filtration aids in uranium ore processing

    International Nuclear Information System (INIS)

    Ford, H.L.; Levine, N.M.; Risdon, A.L.

    1975-01-01

    The patent describes a process whereby improved flocculation efficiency and filtration of carbonate leached uranium ore pulps are obtained by treating the filter feed slurry with an aqueous solution of hydroxyalkyl guar. (J.R.)

  9. GelTouch

    DEFF Research Database (Denmark)

    Miruchna, Viktor; Walter, Robert; Lindlbauer, David

    2015-01-01

    We present GelTouch, a gel-based layer that can selectively transition between soft and stiff to provide tactile multi-touch feedback. It is flexible, transparent when not activated, and contains no mechanical, electromagnetic, or hydraulic components, resulting in a compact form factor (a 2mm thin...... touchscreen layer for our prototype). The activated areas can be morphed freely and continuously, without being limited to fixed, predefined shapes. GelTouch consists of a poly(N-isopropylacrylamide) gel layer which alters its viscoelasticity when activated by applying heat (>32 C). We present three different...

  10. Thorium inorganic gels

    International Nuclear Information System (INIS)

    Genet, M.; Brandel, V.

    1988-01-01

    The optimum pH and concentration values of thorium salts and oxoacids or oxoacid salts which lead to transparent and stable inorganic gels have been determined. The isotherm drying process of the gel at 50 0 C leads successively to a partly dehydrated gel, then, to the formation of an unusual liquid phase and, finally to a dry amorphous solid phase which is still transparent. This kind of transparent inorganic gels and amorphous phase can be used as matrices for spectroscopic studies [fr

  11. 40 CFR 141.719 - Additional filtration toolbox components.

    Science.gov (United States)

    2010-07-01

    ... taken from a surface water or GWUDI source. A cap, such as GAC, on a single stage of filtration is not... separate stage of filtration if both filtration stages treat entire plant flow taken from a surface water... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Additional filtration toolbox...

  12. Cyanocobalamin Nasal Gel

    Science.gov (United States)

    ... to supply extra vitamin B12 to people who need unusually large amounts of this vitamin because they are pregnant or have certain diseases. ... Cyanocobalamin nasal gel will supply you with enough vitamin B12 only as ... it regularly. You may need to use cyanocobalamin nasal gel every week for ...

  13. Sealing wells with gel

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, E C

    1967-10-01

    A new system is being used in Mexico to temporarily plug producing wells. The temporary seal is a gel with a catalyst. The use of this temporary plug allows gas-lift wells to be taken off production in order to carry out emergency repairs. The gel solidifies by the action of the catalyst to a high temperature (70 - 150/sup 0/C). By locating the bottom of the tubing at the top of the production interval, the gel material will go into the permeable formation, and immediately set. When the gel has solidified, it seals off the horizon that must not be stimulated, and leaves the others exposed to the acid action. When the treatment is finished, the gel, by action of the catalyst, is liquefied and removed from the formation, being produced with the oil.

  14. EM Task 9 - Centrifugal membrane filtration

    International Nuclear Information System (INIS)

    Stepan, Daniel J.; Stevens, Bradley G.; Hetland, Melanie D.

    1999-01-01

    The overall project consists of several integrated research phases related to the applicability, continued development, demonstration, and commercialization of the SpinTek centrifugal membrane filtration process. Work performed during this reporting period consisted of Phase 2 evaluation of the SpinTek centrifugal membrane filtration technology and Phase 3, Technology Partnering. During Phase 1 testing conducted at the EERC using the SpinTek ST-IIL unit operating on a surrogate tank waste, a solids cake developed on the membrane surface. The solids cake was observed where linear membrane velocities were less than 17.5 ft/s and reduced the unobstructed membrane surface area up to 25%, reducing overall filtration performance. The primary goal of the Phase 2 research effort was to enhance filtration performance through the development and testing of alternative turbulence promoter designs. The turbulence promoters were designed to generate a shear force across the entire membrane surface sufficient to maintain a self-cleaning membrane capability and improve filtration efficiency and long-term performance. Specific Phase 2 research activities included the following: System modifications to accommodate an 11-in.-diameter, two-disk rotating membrane assembly; Development and fabrication of alternative turbulence promoter designs; Testing and evaluation of the existing and alternative turbulence promoters under selected operating conditions using a statistically designed test matrix; and Data reduction and analysis; The objective of Phase 3 research was to demonstrate the effectiveness of SpinTek's centrifugal membrane filtration as a pretreatment to remove suspended solids from a liquid waste upstream of 3M's WWL cartridge technology for the selective removal of technetium (Tc)

  15. Vacuum distillation/vapor filtration water recovery

    Science.gov (United States)

    Honegger, R. J.; Neveril, R. B.; Remus, G. A.

    1974-01-01

    The development and evaluation of a vacuum distillation/vapor filtration (VD/VF) water recovery system are considered. As a functional model, the system converts urine and condensates waste water from six men to potable water on a steady-state basis. The system is designed for 180-day operating durations and for function on the ground, on zero-g aircraft, and in orbit. Preparatory tasks are summarized for conducting low gravity tests of a vacuum distillation/vapor filtration system for recovering water from urine.

  16. Statistical data filtration in neutron coincidence counting

    International Nuclear Information System (INIS)

    Beddingfield, D.H.; Menlove, H.O.

    1992-11-01

    We assessed the effectiveness of statistical data filtration to minimize the contribution of matrix materials in 200-ell drums to the nondestructive assay of plutonium. Those matrices were examined: polyethylene, concrete, aluminum, iron, cadmium, and lead. Statistical filtration of neutron coincidence data improved the low-end sensitivity of coincidence counters. Spurious data arising from electrical noise, matrix spallation, and geometric effects were smoothed in a predictable fashion by the statistical filter. The filter effectively lowers the minimum detectable mass limit that can be achieved for plutonium assay using passive neutron coincidence counting

  17. The Perspective of Riverbank Filtration in China

    Science.gov (United States)

    Li, J.; Teng, Y.; Zhai, Y.; Zuo, R.

    2014-12-01

    Sustainable drinking water supply can affect the health of people, and the surrounding ecosystems. According to statistics of the monitoring program of drinking water sources in 309 at or above prefecture level of China in 2013, the major pollutants index were total phosphorus, ammonia and manganese in surface drinking water sources, respectively, iron, ammonia and manganese in groundwater drinking water sources, respectively. More than 150 drinking water emergency environmental accidents happened since 2006, 52 of these accidents led to the disruption of water supply in waterworks, and a population of over ten million were affected. It indicated that there is a potential risk for people's health by the use of river water directly and it is necessary to require alternative techniques such as riverbank filtration for improving the drinking water quality. Riverbank filtration is an inexpensive natural process, not only smoothing out normal pollutant concentration found in surface water but also significantly reducing the risk from such emergency events as chemical spill into the river. Riverbank filtration technique has been used in many countries more than 100 years, including China. In China, in 1950s, the bank infiltration technique was first applied in northeast of China. Extensive bank infiltration application was conducted in 1980s, and more than 300 drinking water sources utilities bank infiltration established mainly near the Songhua River Basin, the Yellow River Basin, Haihe River Basin. However, the comparative lack of application and researches on riverbank filtration have formed critical scientific data gap in China. As the performance of riverbank filtration technique depend on not only the design and setting such as well type, pumping rate, but also the local hydrogeology and environmental properties. We recommend more riverbank filtration project and studies to be conducted to collect related significant environmental geology data in China

  18. Industrial investigations of the liquid steel filtration

    Directory of Open Access Journals (Sweden)

    K. Janiszewski

    2014-07-01

    Full Text Available Hitherto existing investigations concerning the ceramic filter use in the steel making processes have given good results. The obtained results of filtration have proved that this method may be used as an effective and cheap way of steel filtration from non-metallic inclusions. Placing filters in the tundish is the best location considering the limitation of the possibility of secondary pollution of steel. Yet, the results presented in this paper, of an experiment prepared and carried out in the industrial environment, are the only positive results obtained, which are connected with so much quantities of liquid steel processed with use of the multi-hole ceramic filters.

  19. Salt disposition alternatives filtration at SRTC

    International Nuclear Information System (INIS)

    Walker, B. W.; Hobbs, D.

    2000-01-01

    Several of the prospective salt disposition alternative technologies require a monosodium titanate (MST) contact to remove strontium and actinides from inorganic salt solution feedstock. This feedstock also contains sludge solids from waste removal operations and may contain defoamers added in the evaporator systems. Filtration is required to remove the sludge and MST solids before sending the salt solution for further processing. This report describes testing performed using the Parallel Theological Experimental Filter (PREF). The PREF contains two single tube Mott sintered metal crossflow filters. For this test one filter was isolated so that the maximum velocities could be achieved. Previous studies showed slurries of MST and sludge in the presence of sodium tetraphenylborate (NaTPB) were filterable since the NaTPB slurry formed a filter cake which aided in removing the smaller MST and sludge particles. Some of the salt disposition alternative technologies do not use NaTPB raising the question of how effective crossflow filtration is with a feed stream containing only sludge and MST. Variables investigated included axial velocity, transmembrane pressure, defoamer effects, and solids concentration (MST and sludge). Details of the tests are outlined in the technical report WSRC-RP-98-O0691. Key conclusions from this study are: (1) Severe fouling of the Mott sintered metal filter did not occur with any of the solutions filtered. (2) The highest fluxes, in the range of .46 to 1.02 gpm/f 2 , were obtained when salt solution decanted from settled solids was fed to the filter. These fluxes would achieve 92 to 204 gpm filtrate production for the current ITP filters. The filtrate fluxes were close to the flux of 0.42 gpm/f 2 reported for In Tank Precipitation Salt Solution by Morrisey. (3) For the range of solids loading studied, the filter flux ranged from .04 to .17 gpm/f 2 which would result in a filtrate production rate of 9 to 31 gpm for the current HP filter. (4

  20. Polymer gel dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Baldock, C [Institute of Medical Physics, School of Physics, University of Sydney (Australia); De Deene, Y [Radiotherapy and Nuclear Medicine, Ghent University Hospital (Belgium); Doran, S [CRUK Clinical Magnetic Resonance Research Group, Institute of Cancer Research, Surrey (United Kingdom); Ibbott, G [Radiation Physics, UT M D Anderson Cancer Center, Houston, TX (United States); Jirasek, A [Department of Physics and Astronomy, University of Victoria, Victoria, BC (Canada); Lepage, M [Centre d' imagerie moleculaire de Sherbrooke, Departement de medecine nucleaire et de radiobiologie, Universite de Sherbrooke, Sherbrooke, QC (Canada); McAuley, K B [Department of Chemical Engineering, Queen' s University, Kingston, ON (Canada); Oldham, M [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Schreiner, L J [Cancer Centre of South Eastern Ontario, Kingston, ON (Canada)], E-mail: c.baldock@physics.usyd.edu.au, E-mail: yves.dedeene@ugent.be

    2010-03-07

    Polymer gel dosimeters are fabricated from radiation sensitive chemicals which, upon irradiation, polymerize as a function of the absorbed radiation dose. These gel dosimeters, with the capacity to uniquely record the radiation dose distribution in three-dimensions (3D), have specific advantages when compared to one-dimensional dosimeters, such as ion chambers, and two-dimensional dosimeters, such as film. These advantages are particularly significant in dosimetry situations where steep dose gradients exist such as in intensity-modulated radiation therapy (IMRT) and stereotactic radiosurgery. Polymer gel dosimeters also have specific advantages for brachytherapy dosimetry. Potential dosimetry applications include those for low-energy x-rays, high-linear energy transfer (LET) and proton therapy, radionuclide and boron capture neutron therapy dosimetries. These 3D dosimeters are radiologically soft-tissue equivalent with properties that may be modified depending on the application. The 3D radiation dose distribution in polymer gel dosimeters may be imaged using magnetic resonance imaging (MRI), optical-computerized tomography (optical-CT), x-ray CT or ultrasound. The fundamental science underpinning polymer gel dosimetry is reviewed along with the various evaluation techniques. Clinical dosimetry applications of polymer gel dosimetry are also presented. (topical review)

  1. Two-dimensional gel electrophoresis of selenized yeast and autoradiography of 75Se-containing proteins

    International Nuclear Information System (INIS)

    Chery, C.C.; Dumont, E.; Cornelis, R.; Moens, L.

    2001-01-01

    Two-dimensional high-resolution gel electrophoresis (2DE) has been applied to the fractionation of 75 Se-containing proteins in yeast, grown in 75 Se-containing medium, and autoradiography was used for detection of the 75 Se-containing proteins. Gel filtration and ultrafiltration were used to check whether the selenium side-chains were stable in the presence of the chemicals used for lysis and 2DE. The mass distribution of the selenium-containing proteins was estimated by use of gel filtration and the results were compared with the distribution obtained by 2DE. A 2DE map of selenium-containing proteins in yeast is presented, and compared with a total protein map of yeast. (orig.)

  2. Filtration of engineered nanoparticles using porous membranes

    NARCIS (Netherlands)

    Trzaskus, Krzystof

    2016-01-01

    The research presented in this thesis aims at providing a better understanding of the fundamental aspects responsible for nanoparticle removal and fouling development during filtration of engineered nanoparticles. The emphasis is put on the role of interparticle interactions in the feed solution,

  3. Dynamic membrane filtration in tangential flow

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Oil-containing waste water is produced in many cleaning processes and also on production of compressed air. Dynamic membrane filtration in the tangential flow mode has proved effective in the treatment of these stable emulsions. The possible applications of ceramic membrane filters are illustrated for a variety of examples. (orig.) [de

  4. Filtration aids in uranium ore processing

    International Nuclear Information System (INIS)

    Ford, H.L.; Levine, N.M.; Risdon, A.R.

    1975-01-01

    A process of improving the filtration efficiency and separation of uranium ore pulps obtained by carbonate leaching of uranium ore which comprises treating said ore pulps with an aqueous solution of hydroxyalkyl guar selected from the group consisting of hydroxyethyl and hydroxypropyl guar in the amount of 0.1 and 2.0 pounds of hydroxyalkyl guar per ton of uranium ore

  5. Filtration engineering study to upgrade the ETF

    International Nuclear Information System (INIS)

    McDonald, F.N.N.

    1995-01-01

    Filtration technologies are evaluated which have potential to augment or upgrade the 200 Area Effluent Treatment Facility. The study was written in anticipation of treating future waste waters that have high fouling potentials. The Three ultrafilters judged to be capable of treating future waste waters are: hollow fiber, tubular, and centrifugal

  6. Water Filtration through Homogeneous Granulated Charge

    Directory of Open Access Journals (Sweden)

    A. M. Krautsou

    2005-01-01

    Full Text Available General relationship for calculation of water filtration through homogeneous granulated charge has been obtained. The obtained relationship has been compared with experimental data. Discrepancies between calculated and experimental values do not exceed 6 % throughout the entire investigated range.

  7. Organic micropollutant removal during river bank filtration

    NARCIS (Netherlands)

    Bertelkamp, C.

    2015-01-01

    This study investigated the factors influencing the main removal mechanisms (adsorption and biodegradation) for organic micropollutant (OMP) removal during river bank filtration (RBF) and the possibility of developing a predictive model of this process for OMP removal during RBF. Chapter 2 analysed

  8. Design of Autonomous Gel Actuators

    Directory of Open Access Journals (Sweden)

    Shuji Hashimoto

    2011-01-01

    Full Text Available In this paper, we introduce autonomous gel actuators driven by chemical energy. The polymer gels prepared here have cyclic chemical reaction networks. With a cyclic reaction, the polymer gels generate periodical motion. The periodic motion of the gel is produced by the chemical energy of the oscillatory Belouzov-Zhabotinsky (BZ reaction. We have succeeded in making synthetic polymer gel move autonomously like a living organism. This experimental fact represents the great possibility of the chemical robot.

  9. Review of Fricke gel dosimeters

    International Nuclear Information System (INIS)

    Schreiner, L J

    2004-01-01

    The innovation of adding a gel matrix to the traditional Fricke dosimeter to stabilize geometric information established the field of gel dosimetry for radiation therapy. A discussion of Fricke gels provides an overview of the issues that determine the dose response of all gel dosimeters in general. In this paper we review some of the features of Fricke systems to illustrate these issues and, in addition, to motivate renewed clinical interest in Fricke gels

  10. A simple gel electrophoresis method for separating polyhedral gold nanoparticles

    Science.gov (United States)

    Kim, Suhee; Lee, Hye Jin

    2015-07-01

    In this paper, a simple approach to separate differently shaped and sized polyhedral gold nanoparticles (NPs) within colloidal solutions via gel electrophoresis is described. Gel running parameters for separating efficiently gold NPs including gel composition, added surfactant types and applied voltage were investigated. The plasmonic properties and physical structure of the separated NPs extracted from the gel matrix were then investigated using transmission electron microscopy (TEM) and UV-vis spectrophotometry respectively. Data analysis revealed that gel electrophoresis conditions of a 1.5 % agarose gel with 0.1 % sodium dodecyl sulfate (SDS) surfactant under an applied voltage of 100 V resulted in the selective isolation of ~ 50 nm polyhedral shaped gold nanoparticles. Further efforts are underway to apply the method to purify biomolecule-conjugated polyhedral Au NPs that can be readily used for NP-enhanced biosensing platforms.

  11. OPTIMIZATION OF THE PROCESS OF DRYING THE FILTRATE DISTILLERY DREGS

    Directory of Open Access Journals (Sweden)

    A. A. Shevtsov

    2013-01-01

    Full Text Available The interactions of various factors affecting the process of drying the filtrate distillery dregs are investigated. Rational conditions for the process of drying the filtrate distillery dregs in a spray dryer are obtained.

  12. 3D MR gel dosimetry with lung equivalent gel

    International Nuclear Information System (INIS)

    Scherer, J.; Solleder, M.; Schiessl, I.; Bogner, L.; Herbst, M.

    1998-01-01

    The MR gel dosimetry is used to verify complex 3D treatment plans. Till now this method served only for dose evaluation in homogeneous phantoms. On the way to build a heterogeneous anthropomorphic gel phantom, a lung equivalent gel with the density 0.4 g/cm 3 was developed. First experiments show a 1.55 times higher dose reponse in the low density gel (LD gel). The comparison of a dose distribution in a gel/LD gel/gel slab phantom with Monte Carlo calculations shows good agreement within 5%. More over the accuray of the measuring device magnetic resonance imager was studied in respect to the now exclusive digital image processing with the software MRD (MR dosimetry). Because of the dimensions of the Fricke gel phantom an artefact correction, based on the data from the unirradiated phantom proved to be essential. (orig.) [de

  13. Structure of mineral gels

    International Nuclear Information System (INIS)

    Miranda Salvado, I.M.; Margaca, F.M.A.; Teixeira, J.

    1999-01-01

    Small Angle Neutron Scattering (SANS) measurements have been performed to investigate the nanoscale structure of materials of the systems xTiO 2 -(1-x)SiO 2 and xZrO 2 -(1-x)SiO 2 with x ≤ 10 mol % at different processing stages. The materials were prepared by sol-gel using the alkoxides method, in strong acidic conditions. Samples were studied as xerogels heat-treated at 120 and 850 deg. C and as wet gels at gel point and after aging. All samples showed identical microstructure at gel point, extended linear chains ∼10 nm long. The aged gel has a mass fractal structure with fractal dimension of 1.7 - 1.9. The 120 deg. C heat-treated xerogels show homogeneous oxide regions with mass fractal structure. For the 850 deg. C heat-treated xerogel the oxide regions average size has reduced and it has densified as compared to 120 deg. C heat-treated sample. (author)

  14. Determination of chromate ion in drilling mud filtrates

    International Nuclear Information System (INIS)

    Whitfill, D.

    1980-01-01

    A method of determining the amount of chromate ion in an aqueous drilling mud filtrate containing organic color bodies such as lignosulfate wherein the method comprises: (A) treating the aqueous filtrate with an effective amount of hydrogen peroxide to destroy said color bodies, and (B) measuring the amount of chromate ion in the filtrate by means of a spectrophotometer

  15. 40 CFR 141.174 - Filtration sampling requirements.

    Science.gov (United States)

    2010-07-01

    ... PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced Filtration and Disinfection... water system subject to the requirements of this subpart that provides conventional filtration treatment... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Filtration sampling requirements. 141...

  16. 40 CFR 141.71 - Criteria for avoiding filtration.

    Science.gov (United States)

    2010-07-01

    ... PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Filtration and Disinfection § 141.71 Criteria for avoiding filtration. A public water system that uses a surface water source must meet all of...)(C)(iii), that filtration is required. A public water system that uses a ground water source under...

  17. 21 CFR 177.2910 - Ultra-filtration membranes.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ultra-filtration membranes. 177.2910 Section 177... Components of Articles Intended for Repeated Use § 177.2910 Ultra-filtration membranes. Ultra-filtration membranes identified in paragraphs (a)(1), (a)(2), (a)(3), and (a)(4) of this section may be safely used in...

  18. The effect of filter cake viscoelasticity on filtration

    DEFF Research Database (Denmark)

    Christensen, Morten Lykkegaard

    , it is difficult to use the existing mathematical filtration models to simulate and optimise the filtration process. Activated sludge as well as synthetic model particles has been filtrated in this project. The study shows that compression of the formed filter cake is a time dependent process, and not only...

  19. Gel electrolytes and electrodes

    Science.gov (United States)

    Fleischmann, Sven; Bunte, Christine; Mikhaylik, Yuriy V.; Viner, Veronika G.

    2017-09-05

    Gel electrolytes, especially gel electrolytes for electrochemical cells, are generally described. In some embodiments, the gel electrolyte layers comprise components a) to c). Component a) may be at least one layer of at least one polymer comprising polymerized units of: a1) at least one monomer containing an ethylenically unsaturated unit and an amido group and a2) at least one crosslinker. Component b) may be at least one conducting salt and component c) may be at least one solvent. Electrodes may comprise the components a), d) and e), wherein component a) may be at least one layer of at least one polymer as described herein. Component d) may be at least one electroactive layer and component e) may be at least one ceramic layer. Furthermore, electrochemical cells comprising component a) which may be at least one layer of at least one polymer as described herein, are also provided.

  20. Sorption of polycyclic aromatic hydrocarbons (PAH) during the filtration of water samples

    International Nuclear Information System (INIS)

    Herbert, M.; Schueth, C.; Pyka, W.

    1992-01-01

    Filtration experiments were preformed for three selected polycyclic aromatic hydrocarbons (PAH-Fluorene, Fluoranthene and Benz(b)-fluoranthene) dissolved in water by varying filter materials, filter-pore sizes and filter equipment. The rate of recovery of PAH depended on the materials and methods applied. Organic filter materials showed a by far stronger sorption than inorganic materials. The losses for organic filters increased up to 100% with decreasing pore-size. The percentage loss was observed to increase with increasing octanol-water distribution coefficient (K OW ). Saturation tests revealed that the amount of water, necessary to saturate the filtration apparatus with and without filter-paper, also increased with the K OW . For BBF several liters would be necessary for saturation. It can be concluded, that the filtration of water samples, analysed for PAH, can lead to considerable errors in the analytical results, particularly for those PAH with log K OW larger than 5. (orig.)

  1. Hanford phosphate precipitation filtration process evaluation

    International Nuclear Information System (INIS)

    Walker, B.W.; McCabe, D.J.

    1997-01-01

    The purpose of this filter study was to evaluate cross-flow filtration as effective solid-liquid separation technology for treating Hanford wastes, outline operating conditions for equipment, examine the expected filter flow rates, and determine proper cleaning. A proposed Hanford waste pre-treatment process uses sodium hydroxide at high temperature to remove aluminum from sludge. This process also dissolves phosphates. Upon cooling to 40 degrees centigrade the phosphates form a Na7(PO4)2F9H2O precipitate which must be removed prior to further treatment. Filter studies were conducted with a phosphate slurry simulant to evaluate whether 0.5 micron cross-flow sintered metal Mott filters can separate the phosphate precipitate from the wash solutions. The simulant was recirculated through the filters at room temperature and filtration performance data was collected

  2. Primary effluent filtration for coastal discharges

    Energy Technology Data Exchange (ETDEWEB)

    Cooper-Smith, G.D. [Yorkshire Water Services, Huddersfield (United Kingdom); Rundle, H. [The Capital Controls Group, Nottingham (United Kingdom)

    1998-12-31

    The use of a Tetra Deep Bed filter demonstration unit to treat primary effluent (Primary Effluent Filtration, PEF) was investigated. PEF proved capable of achieving the UWWTD primary standard, even when the primary stage performs poorly, but is not a cost-effective alternative to chemically assisted settlement. Results demonstrated that using a 1.5 to 2.2 mm grade medium, a filtration rate of 5 m/h, three backwashes a day and dosing 40 mg/l of PAXXL60 (a polyaluminium silicte) an average effluent quality of 20 mg/l BOD and 15 mgl/l total solid could be achieved. UV disinfection produced an effluent which complied with the Bathing Water Directive imperative requirement. A high enterovirus kill was also achieved. However, considerable additional work would be required before PEF could be considered suitable for full-scale applications. (orig.)

  3. Ultrasonic filtration of industrial chemical solutions

    Science.gov (United States)

    Cosma, T.

    1974-01-01

    The practical results obtained as a result of filtering industrial chemical solutions under continuous flow conditions with the aid of an ultrasonic filter are presented. The main part of the assembly consists of an ultrasonic generator with an output power of about 400 W and the filtration assembly, in which there is a magnetostrictive amplifier constructed for 20.5 kHz. In addition to ensuring a continuous flow of filtered solution, ultrasonic filters can be replaced or cleaned at intervals of time that are 8-10 times greater than in the case of mechanical filters. They yield considerably better results as far as the size of the filtered particles is concerned. The parameters on which filtration quality depends are also presented.

  4. Air filtration and indoor air quality

    DEFF Research Database (Denmark)

    Bekö, Gabriel

    2006-01-01

    Demands for better indoor air quality are increasing, since we spend most of our time indoors and we are more and more aware of indoor air pollution. Field studies in different parts of the world have documented that high percentage of occupants in many offices and buildings find the indoor air...... decent ventilation and air cleaning/air filtration, high indoor air quality cannot be accomplished. The need for effective air filtration has increased with increasing evidence on the hazardous effects of fine particles. Moreover, the air contains gaseous pollutants, removal of which requires various air...... cleaning techniques. Supply air filter is one of the key components in the ventilation system. Studies have shown that used ventilation filters themselves can be a significant source of indoor air pollution with consequent impact on perceived air quality, sick building syndrome symptoms and performance...

  5. High Temperature Particle Filtration Technology; TOPICAL

    International Nuclear Information System (INIS)

    Besmann, T.M.

    2001-01-01

    High temperature filtration can serve to improve the economic, environmental, and energy performance of chemical processes. This project was designed to evaluate the stability of filtration materials in the environments of the production of dimethyldichlorosilane (DDS). In cooperation with Dow Corning, chemical environments for the fluidized bed reactor where silicon is converted to DDS and the incinerator where vents are cornbusted were characterized. At Oak Ridge National Laboratory (ORNL) an exposure system was developed that could simulate these two environments. Filter samples obtained from third parties were exposed to the environments for periods up to 1000 hours. Mechanical properties before and after exposure were determined by burst-testing rings of filter material. The results indicated that several types of filter materials would likely perform well in the fluid bed environment, and two materials would be good candidates for the incinerator environment

  6. Enlargement of filtration with finance in view

    CERN Document Server

    Aksamit, Anna

    2017-01-01

    This volume presents classical results of the theory of enlargement of filtration. The focus is on the behavior of martingales with respect to the enlarged filtration and related objects. The study is conducted in various contexts including immersion, progressive enlargement with a random time and initial enlargement with a random variable.  The aim of this book is to collect the main mathematical results (with proofs) previously spread among numerous papers, great part of which is only available in French. Many examples and applications to finance, in particular to credit risk modelling and the study of asymmetric information, are provided to illustrate the theory. A detailed summary of further connections and applications is given in bibliographic notes which enables to deepen study of the topic.  This book fills a gap in the literature and serves as a guide for graduate students and researchers interested in the role of information in financial mathematics and in econometric science. A basic knowledge of...

  7. Osmosis, filtration and fracture of porous media

    International Nuclear Information System (INIS)

    Suarez Antola, R.

    2001-01-01

    Filtration was produced in a small scale physical model of a granular porous medium of cylindrical shape.The same volume flow was obtained either applying a difference in hydrostatic pressure or in osmotic pressure.In the first case a process of sustained erosion ending in an hydraulic short circuit was observed,while in the second case the material remained stable.This paradoxical strength behaviour is explained using some results from differential geometry,classical field theory and thermo-kinetic theory.The fracture process of a continuous matrix in a porous medium under the combined effect of filtration and external mechanical loads in then considered.The obtained results can be applied to the textural and compressive strength of wet concrete

  8. Electroblotting from Polyacrylamide Gels.

    Science.gov (United States)

    Goldman, Aaron; Ursitti, Jeanine A; Mozdzanowski, Jacek; Speicher, David W

    2015-11-02

    Transferring proteins from polyacrylamide gels onto retentive membranes is now primarily used for immunoblotting. A second application that was quite common up to about a decade ago was electroblotting of proteins for N-terminal and internal sequencing using Edman chemistry. This unit contains procedures for electroblotting proteins from polyacrylamide gels onto a variety of membranes, including polyvinylidene difluoride (PVDF) and nitrocellulose. In addition to the commonly used tank or wet transfer system, protocols are provided for electroblotting using semidry and dry systems. This unit also describes procedures for eluting proteins from membranes using detergents or acidic extraction with organic solvents for specialized applications. Copyright © 2015 John Wiley & Sons, Inc.

  9. Aerosol filtration with metallic fibrous filters

    International Nuclear Information System (INIS)

    Klein, M.; Goossens, W.R.A.

    1983-01-01

    The filtration efficiency of stainless steel fibrous filters (BEKIPOR porous mats and sintered webs) is determined using submicronic monodisperse polystyrene aerosols. Lasers spectrometers are used for the aerosol measurements. The parameters varied are the fiber diameter, the number of layers, the aerosol diameter and the superficial velocity. Two selected types of filters are tested with polydisperse methylene blue aerosols to determine the effect of bed loading on the filter performance and to test washing techniques for the regeneration of the filter

  10. Diatomite releases silica during spirit filtration

    OpenAIRE

    Gómez Benítez, Juan; Gil Montero, María Luisa Almoraima; De la Rosa Fox, Nicolas; Alguacil, Marcos

    2014-01-01

    The purpose of this study was to ascertain whether diatomite is an inert filter aid during spirit filtration. Surely, any compound with a negative effect on the spirit composition or the consumer’s health could be dissolved. In this study different diatomites were treated with 36% vol. ethanol/water mixtures and the amounts and structures of the extracted compounds were determined. Furthermore, Brandy de Jerez was diatomite- and membrane-filtered at different temperatures and the silicon cont...

  11. Portable Hybrid Powered Water Filtration Device

    Directory of Open Access Journals (Sweden)

    Maria Lourdes V. Balansay

    2015-08-01

    Full Text Available The existing water filtration device has features that can be developed to be more useful and functional during emergency situations. The project’s development has been aided by following provisions in PEC, NEC, NEMA and Philippine National Standard for Safe Drinking Water provide standards for the construction of the project. These standards protect both the prototype and the user. These also served as guide for the maintenance of every component. The design of the portable hybrid powered water filtration device shows that the project has more advanced features such as portability and the power supply used such as photovoltaic module solar cells and manually operated generator. This also shows its effectiveness and reliability based on the results of discharging test, water quality test and water production test. Based on analysis of the overall financial aspects, the machine can be profitable and the amount of revenue and operating cost will increase as years pass. Using the proper machine/ tools and methods of fabrication helps in easy assembly of the project. The materials and components used are cost effective and efficient. The best time for charging the battery using solar panel is 9:00 am onwards while the hand crank generator is too slow because the generated current is little. The water filtration device is very efficient regarding the operating hours and water production. The machine may have a great effect to society and economy in generation of clean available water at less cost.

  12. Filtration system for nuclear power plant

    International Nuclear Information System (INIS)

    Otani, Takashi; Nakamizo, Hiroshi.

    1991-01-01

    The filtration system of the present invention comprises a filtering device incorporating ceramic filament element bundles, a pool return line for returning filtrates to a side banker pool or fuel storage pool, a waste sludge discharge line for discharging waste sludges captured in the filter elements by way of washing operation and a settling separation vessel. Ceramics of excellent radiation resistance and having an extremely thin multi-layered structure at the surface are used for the filter elements. Highly radioactive cruds captured at the surface of the elements by liquid passage are removed by supplying water or gas in a pulsative manner in the direction opposite to the liquid passage thereby cleaning the surface of the elements at a high speed. The thus removed high radioactive cruds are concentrically confined within the settling separation layer by gravitational settling separation. Thus, there is no more necessary for disposing the filtration element bundles after use, so that the amount of wastes can be reduced, the radiation dosage can be lowered and the facility can be simplified. (N.H.)

  13. Direct filtration of Biesbosch water and Algae and water treatment in the Netherlands : 3rd Direct Filtration Seminar

    NARCIS (Netherlands)

    Petrusevski, B.; Vlaski, A.; Van Breemen, A.N.; Alaerts, G.J.

    1993-01-01

    This presentation summarises basic information on direct filtration, and demonstrates the main research findings, related to the performance of simple in-line direct filtration. The results reported are part of a comprehensive ongoing research programm "Direct filtration of Biesbosch water"

  14. Solution Structure of the Tandem Acyl Carrier Protein Domains from a Polyunsaturated Fatty Acid Synthase Reveals Beads-on-a-String Configuration

    KAUST Repository

    Trujillo, Uldaeliz

    2013-02-28

    The polyunsaturated fatty acid (PUFA) synthases from deep-sea bacteria invariably contain multiple acyl carrier protein (ACP) domains in tandem. This conserved tandem arrangement has been implicated in both amplification of fatty acid production (additive effect) and in structural stabilization of the multidomain protein (synergistic effect). While the more accepted model is one in which domains act independently, recent reports suggest that ACP domains may form higher oligomers. Elucidating the three-dimensional structure of tandem arrangements may therefore give important insights into the functional relevance of these structures, and hence guide bioengineering strategies. In an effort to elucidate the three-dimensional structure of tandem repeats from deep-sea anaerobic bacteria, we have expressed and purified a fragment consisting of five tandem ACP domains from the PUFA synthase from Photobacterium profundum. Analysis of the tandem ACP fragment by analytical gel filtration chromatography showed a retention time suggestive of a multimeric protein. However, small angle X-ray scattering (SAXS) revealed that the multi-ACP fragment is an elongated monomer which does not form a globular unit. Stokes radii calculated from atomic monomeric SAXS models were comparable to those measured by analytical gel filtration chromatography, showing that in the gel filtration experiment, the molecular weight was overestimated due to the elongated protein shape. Thermal denaturation monitored by circular dichroism showed that unfolding of the tandem construct was not cooperative, and that the tandem arrangement did not stabilize the protein. Taken together, these data are consistent with an elongated beads-on-a-string arrangement of the tandem ACP domains in PUFA synthases, and speak against synergistic biocatalytic effects promoted by quaternary structuring. Thus, it is possible to envision bioengineering strategies which simply involve the artificial linking of multiple ACP

  15. Solution Structure of the Tandem Acyl Carrier Protein Domains from a Polyunsaturated Fatty Acid Synthase Reveals Beads-on-a-String Configuration

    KAUST Repository

    Trujillo, Uldaeliz; Vá zquez-Rosa, Edwin; Oyola-Robles, Delise; Stagg, Loren J.; Vassallo, David A.; Vega, Irving E.; Arold, Stefan T.; Baerga-Ortiz, Abel

    2013-01-01

    The polyunsaturated fatty acid (PUFA) synthases from deep-sea bacteria invariably contain multiple acyl carrier protein (ACP) domains in tandem. This conserved tandem arrangement has been implicated in both amplification of fatty acid production (additive effect) and in structural stabilization of the multidomain protein (synergistic effect). While the more accepted model is one in which domains act independently, recent reports suggest that ACP domains may form higher oligomers. Elucidating the three-dimensional structure of tandem arrangements may therefore give important insights into the functional relevance of these structures, and hence guide bioengineering strategies. In an effort to elucidate the three-dimensional structure of tandem repeats from deep-sea anaerobic bacteria, we have expressed and purified a fragment consisting of five tandem ACP domains from the PUFA synthase from Photobacterium profundum. Analysis of the tandem ACP fragment by analytical gel filtration chromatography showed a retention time suggestive of a multimeric protein. However, small angle X-ray scattering (SAXS) revealed that the multi-ACP fragment is an elongated monomer which does not form a globular unit. Stokes radii calculated from atomic monomeric SAXS models were comparable to those measured by analytical gel filtration chromatography, showing that in the gel filtration experiment, the molecular weight was overestimated due to the elongated protein shape. Thermal denaturation monitored by circular dichroism showed that unfolding of the tandem construct was not cooperative, and that the tandem arrangement did not stabilize the protein. Taken together, these data are consistent with an elongated beads-on-a-string arrangement of the tandem ACP domains in PUFA synthases, and speak against synergistic biocatalytic effects promoted by quaternary structuring. Thus, it is possible to envision bioengineering strategies which simply involve the artificial linking of multiple ACP

  16. Solution structure of the tandem acyl carrier protein domains from a polyunsaturated fatty acid synthase reveals beads-on-a-string configuration.

    Directory of Open Access Journals (Sweden)

    Uldaeliz Trujillo

    Full Text Available The polyunsaturated fatty acid (PUFA synthases from deep-sea bacteria invariably contain multiple acyl carrier protein (ACP domains in tandem. This conserved tandem arrangement has been implicated in both amplification of fatty acid production (additive effect and in structural stabilization of the multidomain protein (synergistic effect. While the more accepted model is one in which domains act independently, recent reports suggest that ACP domains may form higher oligomers. Elucidating the three-dimensional structure of tandem arrangements may therefore give important insights into the functional relevance of these structures, and hence guide bioengineering strategies. In an effort to elucidate the three-dimensional structure of tandem repeats from deep-sea anaerobic bacteria, we have expressed and purified a fragment consisting of five tandem ACP domains from the PUFA synthase from Photobacterium profundum. Analysis of the tandem ACP fragment by analytical gel filtration chromatography showed a retention time suggestive of a multimeric protein. However, small angle X-ray scattering (SAXS revealed that the multi-ACP fragment is an elongated monomer which does not form a globular unit. Stokes radii calculated from atomic monomeric SAXS models were comparable to those measured by analytical gel filtration chromatography, showing that in the gel filtration experiment, the molecular weight was overestimated due to the elongated protein shape. Thermal denaturation monitored by circular dichroism showed that unfolding of the tandem construct was not cooperative, and that the tandem arrangement did not stabilize the protein. Taken together, these data are consistent with an elongated beads-on-a-string arrangement of the tandem ACP domains in PUFA synthases, and speak against synergistic biocatalytic effects promoted by quaternary structuring. Thus, it is possible to envision bioengineering strategies which simply involve the artificial linking of

  17. gel template method

    Indian Academy of Sciences (India)

    TiO2 nanotubes have been synthesized by sol–gel template method using alumina membrane. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, UV absorption spectrum and X-ray diffraction techniques have been used to investigate the structure, morphology and optical ...

  18. Filtration Efficiency of Functionalized Ceramic Foam Filters for Aluminum Melt Filtration

    Science.gov (United States)

    Voigt, Claudia; Jäckel, Eva; Taina, Fabio; Zienert, Tilo; Salomon, Anton; Wolf, Gotthard; Aneziris, Christos G.; Le Brun, Pierre

    2017-02-01

    The influence of filter surface chemistry on the filtration efficiency of cast aluminum alloys was evaluated for four different filter coating compositions (Al2O3—alumina, MgAl2O4—spinel, 3Al2O3·2SiO2—mullite, and TiO2—rutile). The tests were conducted on a laboratory scale with a filtration pilot plant, which facilitates long-term filtration tests (40 to 76 minutes). This test set-up allows the simultaneous use of two LiMCAs (before and after the filter) for the determination of the efficiency of inclusion removal. The four tested filter surface chemistries exhibited good thermal stability and mechanical robustness after 750 kg of molten aluminum had been cast. All four filter types exhibited a mean filtration efficiency of at least 80 pct. However, differences were also observed. The highest filtration efficiencies were obtained with alumina- and spinel-coated filter surfaces (>90 pct), and the complete removal of the largest inclusions (>90 µm) was observed. The efficiency was slightly lower with mullite- and rutile-coated filter surfaces, in particular for large inclusions. These observations are discussed in relation to the properties of the filters, in particular in terms of, for example, the surface roughness.

  19. Transdermal delivery of paeonol using cubic gel and microemulsion gel

    Science.gov (United States)

    Luo, Maofu; Shen, Qi; Chen, Jinjin

    2011-01-01

    Background The aim of this study was to develop new systems for transdermal delivery of paeonol, in particular microemulsion gel and cubic gel formulations. Methods Various microemulsion vehicles were prepared using isopropyl myristate as an oil phase, polyoxyethylated castor oil (Cremophor® EL) as a surfactant, and polyethylene glycol 400 as a cosurfactant. In the optimum microemulsion gel formulation, carbomer 940 was selected as the gel matrix, and consisted of 1% paeonol, 4% isopropyl myristate, 28% Cremophor EL/polyethylene glycol 400 (1:1), and 67% water. The cubic gel was prepared containing 3% paeonol, 30% water, and 67% glyceryl monooleate. Results A skin permeability test using excised rat skins indicated that both the cubic gel and microemulsion gel formulations had higher permeability than did the paeonol solution. An in vivo pharmacokinetic study done in rats showed that the relative bioavailability of the cubic gel and microemulsion gel was enhanced by about 1.51-fold and 1.28-fold, respectively, compared with orally administered paeonol suspension. Conclusion Both the cubic gel and microemulsion gel formulations are promising delivery systems to enhance the skin permeability of paeonol, in particular the cubic gel. PMID:21904450

  20. Risks of using membrane filtration for trace metal analysis and assessing the dissolved metal fraction of aqueous media - A study on zinc, copper and nickel

    International Nuclear Information System (INIS)

    Hedberg, Yolanda; Herting, Gunilla; Wallinder, Inger Odnevall

    2011-01-01

    Membrane filtration is commonly performed for solid-liquid separation of aqueous solutions prior to trace metal analysis and when assessing 'dissolved' metal fractions. Potential artifacts induced by filtration such as contamination and/or adsorption of metals within the membrane have been investigated for different membrane materials, metals, applied pressures and pre-cleaning steps. Measurements have been conducted on aqueous solutions including well-defined metal standards, ultrapure water, and on runoff water from corroded samples. Filtration using both non-cleaned and pre-cleaned filters revealed contamination and adsorption effects, in particular pronounced for zinc, evident for copper but non-significant for nickel. The results clearly show these artifacts to be non-systematic both for non-cleaned and pre-cleaned membranes. The applied pressure was of minor importance. Measurements of the labile fraction by means of stripping voltammetry clearly elucidate that membrane filtration followed by total metal analysis cannot accurately assess the labile or the dissolved metal fraction. - Highlights: → Membrane filtration for trace metal analysis can introduce significant artifacts. → The dissolved metal fraction cannot be assessed by membrane filtration. → Non-specified filtration procedures are inadequate for scientific studies. → Artifacts caused by membrane filtration need to be addressed by regulators. - Membrane filtration cannot be used to assess the dissolved metal fraction of aqueous media and needs to be defined in detail in standard tests.

  1. Measurement and characterization of filtration efficiencies for prefilter materials used in aerosol filtration

    International Nuclear Information System (INIS)

    Sciortino, J.

    1991-01-01

    In applications where the filtration of large quantities of mixed (liquid and solid) aerosols is desired, a multistage filtration system is often employed. This system consists of a prefilter, a High Efficiency Particulate Air (HEPA) filter, and any number of specialized filters particular to the filtration application. The prefilter removes liquids and any large particles from the air stream, keeping them from prematurely loading the HEPA filter downstream. The HEPA filter eliminates 99.97% of all particulates in the aerosol. The specialized filters downstream of the HEPA filter can be used to remove organic volatiles or other vapors. While the properties of HEPA filters have been extensively investigated, literature characterizing the prefilter is scarce. The purpose of this report is to characterize the efficiency of the prefilter as a function of particle size, nature of the particle (solid or liquid), and the gas flow rate across the face of the prefilter. 1 ref., 4 figs

  2. Aldosterone and glomerular filtration--observations in the general population.

    Science.gov (United States)

    Hannemann, Anke; Rettig, Rainer; Dittmann, Kathleen; Völzke, Henry; Endlich, Karlhans; Nauck, Matthias; Wallaschofski, Henri

    2014-03-10

    Increasing evidence suggests that aldosterone promotes renal damage. Since data on the association between aldosterone and renal function in the general population are sparse, we chose to address this issue. We investigated the associations between the plasma aldosterone concentration (PAC) or the aldosterone-to-renin ratio (ARR) and the estimated glomerular filtration rate (eGFR) in a sample of adult men and women from Northeast Germany. A study population of 1921 adult men and women who participated in the first follow-up of the Study of Health in Pomerania was selected. None of the subjects used drugs that alter PAC or ARR. The eGFR was calculated according to the four-variable Modification of Diet in Renal Disease formula. Chronic kidney disease (CKD) was defined as an eGFR < 60 ml/min/1.73 m2. Linear regression models, adjusted for sex, age, waist circumference, diabetes mellitus, smoking status, systolic and diastolic blood pressures, serum triglyceride concentrations and time of blood sampling revealed inverse associations of PAC or ARR with eGFR (ß-coefficient for log-transformed PAC -3.12, p < 0.001; ß-coefficient for log-transformed ARR -3.36, p < 0.001). Logistic regression models revealed increased odds for CKD with increasing PAC (odds ratio for a one standard deviation increase in PAC: 1.35, 95% confidence interval: 1.06-1.71). There was no statistically significant association between ARR and CKD. Our study demonstrates that PAC and ARR are inversely associated with the glomerular filtration rate in the general population.

  3. Design and Characterization of Electrospun Polyamide Nanofiber Media for Air Filtration Applications

    Directory of Open Access Journals (Sweden)

    Jonas Matulevicius

    2014-01-01

    Full Text Available Electrospun polyamide 6 (PA 6 and polyamide 6/6 (PA 6/6 nanofibers were produced in order to investigate their experimental characteristics with the goal of obtaining filtration relevant fiber media. The experimental design model of each PA nanofibers contained the following variables: polymer concentration, ratio of solvents, nanofiber media collection time, tip-to-collector distance, and the deposition voltage. The average diameter of the fibers, their morphology, basis weight, thickness, and resulting media solidity were investigated. Effects of each variable on the essential characteristics of PA 6/6 and PA 6 nanofiber media were studied. The comparative analysis of the obtained PA 6/6 and PA 6 nanofiber characteristics revealed that PA 6/6 had higher potential to be used in filtration applications. Based on the experimental results, the graphical representation—response surfaces—for obtaining nanofiber media with the desirable fiber diameter and basis weight characteristics were derived. Based on the modelling results the nanofiber filter media (mats were fabricated. Filtration results revealed that nanofiber filter media electrospun from PA6/6 8% (w/vol solutions with the smallest fiber diameters (62–66 nm had the highest filtration efficiency (PA6/6_30 = 84.9–90.9% and the highest quality factor (PA6/6_10 = 0.0486–0.0749 Pa−1.

  4. A rigid porous filter and filtration method

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Ta-Kuan; Straub, Douglas, Straub L.; Dennis, Richard A.

    1998-12-01

    The present invention involves a porous rigid filter comprising a plurality of concentric filtration elements having internal flow passages and forming external flow passages there between. The present invention also involves a pressure vessel containing the filter for the removal of particulate from high pressure particulate containing gases, and further involves a method for using the filter to remove such particulate. The present filter has the advantage of requiring fewer filter elements due to the high surface area- to-volume ratio provided by the filter, requires a reduced pressure vessel size, and exhibits enhanced mechanical design properties, improved cleaning properties, configuration options, modularity and ease of fabrication.

  5. Limitation of releases and filtration by sand

    International Nuclear Information System (INIS)

    Schektman, N.

    1986-01-01

    In the highly hypothetic case of a severe reactor accident, it may lead to an increase of pressure within the containment and up to a value above the calculated pressure. A procedure is necessary in this case to maintain the integrity of the containment to prevent a release of radioactive products to the environment, while controlling in the best way releases. So, EDF and the CEA have developed a device of decompression-filtration of the containment atmosphere, using a free penetration of the containment and a sand box; the device and its operation constitute the U5 procedure [fr

  6. Investigation of Microgranular Adsorptive Filtration System

    Science.gov (United States)

    Cai, Zhenxiao

    Over the past few decades, enormous advances have been made in the application of low-pressure membrane filtration to both drinking water and wastewater treatment. Nevertheless, the full potential of this technology has not been reached, due primarily to limitations imposed by membrane fouling. In drinking water treatment, much of the fouling is caused by soluble and particulate natural organic matter (NOM). Efforts to overcome the problem have focused on removal of NOM from the feed solution, usually by addition of conventional coagulants like alum and ferric chloride (FeCl3) or adsorbents like powdered activated carbon (PAC). While coagulants and adsorbents can remove a portion of the NOM, their performance with respect to fouling control has been inconsistent, often reducing fouling but sometimes having no effect or even exacerbating fouling. This research investigated microgranular adsorptive filtration (muGAF), a process that combines three existing technologies---granular media filtration, packed bed adsorption, and membrane filtration---in a novel way to reduce membrane fouling while simultaneously removing NOM from water. In this technology, a thin layer of micron-sized adsorbent particles is deposited on the membrane prior to delivering the feed to the system. The research reported here represents the first systematic study of muGAF, and the results demonstrate the promising potential of this process. A new, aluminum-oxide-based adsorbent---heated aluminum oxide particles (HAOPs)---was synthesized and shown to be very effective for NOM removal as well as fouling reduction in muGAF systems. muGAF has also been demonstrated to work well with powdered activated carbon (PAC) as the adsorbent, but not as well as when HAOPs are used; the process has also been successful when used with several different membrane types and configurations. Experiments using a wide range of operational parameters and several analytical tools lead to the conclusion that the fouling

  7. Good Filtrations and the Steinberg Square

    DEFF Research Database (Denmark)

    Kildetoft, Tobias

    that tensoring the Steinberg module with a simple module of restricted highest weight gives a module with a good filtration. This result was first proved by Andersen when the characteristic is large enough. In this dissertation, generalizations of those results, which are joint work with Daniel Nakano......, the socle completely determines how a Steinberg square decomposes. The dissertation also investigates the socle of the Steinberg square for a finite group of Lie type, again providing formulas which describe how to find the multiplicity of a simple module in the socle, given information about...

  8. The Gel Generator option

    International Nuclear Information System (INIS)

    Boyd, R.E.

    1999-01-01

    The development of a national policy for guaranteeing an ample supply of 99m Tc to nuclear medicine, involves issues which go beyond the means by which radioactivation is achieved. Indeed, in such an exercise the pragmatic dictates of business and the sensitivities of politics must also be taken into account. Furthermore where a preference towards the nuclear reactor or the potential of cyclotrons is being questioned, the debate is incomplete if the only options that are considered are the fission-based 99 Mo generator versus the direct cyclotron production of 99m Tc. There is a third option (also neutron γ-based), an alternative to the fission 99 Mo generator, which ought not be overlooked. The application of low specific activity (n,γ) 99 Mo to a new type of generator, the Gel Generator, has been the focus of much research, particularly in Australia and more recently in China. After the initial concept had been established in the laboratory, the Australian researchers then undertook a comprehensive program of tests on the Gel Generator to assess its potential, either in the clinical laboratory or the centralised radiopharmacy, for supplying 99m Tc suitable for nuclear medicine. The outcome of this program was a clear indication that the Gel Generator innovation had the capability to provide both technical and economic advantages to the nuclear medicine industry. These advantages are described. Since that time the Gel Generator has been selected for routine use in China where it now satisfies more than 30% of the 99m Tc demand. (author)

  9. Caffeine-catalyzed gels.

    Science.gov (United States)

    DiCiccio, Angela M; Lee, Young-Ah Lucy; Glettig, Dean L; Walton, Elizabeth S E; de la Serna, Eva L; Montgomery, Veronica A; Grant, Tyler M; Langer, Robert; Traverso, Giovanni

    2018-07-01

    Covalently cross-linked gels are utilized in a broad range of biomedical applications though their synthesis often compromises easy implementation. Cross-linking reactions commonly utilize catalysts or conditions that can damage biologics and sensitive compounds, producing materials that require extensive post processing to achieve acceptable biocompatibility. As an alternative, we report a batch synthesis platform to produce covalently cross-linked materials appropriate for direct biomedical application enabled by green chemistry and commonly available food grade ingredients. Using caffeine, a mild base, to catalyze anhydrous carboxylate ring-opening of diglycidyl-ether functionalized monomers with citric acid as a tri-functional crosslinking agent we introduce a novel poly(ester-ether) gel synthesis platform. We demonstrate that biocompatible Caffeine Catalyzed Gels (CCGs) exhibit dynamic physical, chemical, and mechanical properties, which can be tailored in shape, surface texture, solvent response, cargo release, shear and tensile strength, among other potential attributes. The demonstrated versatility, low cost and facile synthesis of these CCGs renders them appropriate for a broad range of customized engineering applications including drug delivery constructs, tissue engineering scaffolds, and medical devices. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Chiromagnetic nanoparticles and gels

    Science.gov (United States)

    Yeom, Jihyeon; Santos, Uallisson S.; Chekini, Mahshid; Cha, Minjeong; de Moura, André F.; Kotov, Nicholas A.

    2018-01-01

    Chiral inorganic nanostructures have high circular dichroism, but real-time control of their optical activity has so far been achieved only by irreversible chemical changes. Field modulation is a far more desirable path to chiroptical devices. We hypothesized that magnetic field modulation can be attained for chiral nanostructures with large contributions of the magnetic transition dipole moments to polarization rotation. We found that dispersions and gels of paramagnetic Co3O4 nanoparticles with chiral distortions of the crystal lattices exhibited chiroptical activity in the visible range that was 10 times as strong as that of nonparamagnetic nanoparticles of comparable size. Transparency of the nanoparticle gels to circularly polarized light beams in the ultraviolet range was reversibly modulated by magnetic fields. These phenomena were also observed for other nanoscale metal oxides with lattice distortions from imprinted amino acids and other chiral ligands. The large family of chiral ceramic nanostructures and gels can be pivotal for new technologies and knowledge at the nexus of chirality and magnetism.

  11. Dynamic optimization of a dead-end filtration trajectory: non-ideal cake filtration

    NARCIS (Netherlands)

    Blankert, B.; Kattenbelt, C.; Betlem, Bernardus H.L.; Roffel, B.

    2007-01-01

    A control strategy aimed at minimizing energy consumption is formulated for non-ideal dead-end cake filtration with an inside-out hollow fiber ultrafiltration membrane system. The non-ideal behavior was assumed to originate from cake compression, non-linear cake resistance and a variable pump

  12. Dynamic optimization of a dead-end filtration trajectory: Blocking filtration laws

    NARCIS (Netherlands)

    Blankert, B.; Betlem, Bernardus H.L.; Roffel, B.

    2006-01-01

    An operating model for dead-end membrane filtration is proposed based on the well-known blocking laws. The resulting model contains three parameters representing, the operating strategy, the fouling mechanism and the fouling potential of the feed. The optimal control strategy is determined by

  13. Nanofiltration and Tight Ultrafiltration Membranes for Natural Organic Matter Removal-Contribution of Fouling and Concentration Polarization to Filtration Resistance.

    Science.gov (United States)

    Winter, Joerg; Barbeau, Benoit; Bérubé, Pierre

    2017-07-02

    Nanofiltration (NF) and tight ultrafiltration (tight UF) membranes are a viable treatment option for high quality drinking water production from sources with high concentrations of contaminants. To date, there is limited knowledge regarding the contribution of concentration polarization (CP) and fouling to the increase in resistance during filtration of natural organic matter (NOM) with NF and tight UF. Filtration tests were conducted with NF and tight UF membranes with molecular weight cut offs (MWCOs) of 300, 2000 and 8000 Da, and model raw waters containing different constituents of NOM. When filtering model raw waters containing high concentrations of polysaccharides (i.e., higher molecular weight NOM), the increase in resistance was dominated by fouling. When filtering model raw waters containing humic substances (i.e., lower molecular weight NOM), the increase in filtration resistance was dominated by CP. The results indicate that low MWCO membranes are better suited for NOM removal, because most of the NOM in surface waters consist mainly of humic substances, which were only effectively rejected by the lower MWCO membranes. However, when humic substances are effectively rejected, CP can become extensive, leading to a significant increase in filtration resistance by the formation of a cake/gel layer at the membrane surface. For this reason, cross-flow operation, which reduces CP, is recommended.

  14. Nanofiltration and Tight Ultrafiltration Membranes for Natural Organic Matter Removal—Contribution of Fouling and Concentration Polarization to Filtration Resistance

    Directory of Open Access Journals (Sweden)

    Joerg Winter

    2017-07-01

    Full Text Available Nanofiltration (NF and tight ultrafiltration (tight UF membranes are a viable treatment option for high quality drinking water production from sources with high concentrations of contaminants. To date, there is limited knowledge regarding the contribution of concentration polarization (CP and fouling to the increase in resistance during filtration of natural organic matter (NOM with NF and tight UF. Filtration tests were conducted with NF and tight UF membranes with molecular weight cut offs (MWCOs of 300, 2000 and 8000 Da, and model raw waters containing different constituents of NOM. When filtering model raw waters containing high concentrations of polysaccharides (i.e., higher molecular weight NOM, the increase in resistance was dominated by fouling. When filtering model raw waters containing humic substances (i.e., lower molecular weight NOM, the increase in filtration resistance was dominated by CP. The results indicate that low MWCO membranes are better suited for NOM removal, because most of the NOM in surface waters consist mainly of humic substances, which were only effectively rejected by the lower MWCO membranes. However, when humic substances are effectively rejected, CP can become extensive, leading to a significant increase in filtration resistance by the formation of a cake/gel layer at the membrane surface. For this reason, cross-flow operation, which reduces CP, is recommended.

  15. EM Task 9 - Centrifugal Membrane Filtration

    International Nuclear Information System (INIS)

    Stevens, B.G.; Stepan, D.J.; Hetland, M.D.

    1998-01-01

    This project is designed to establish the utility of a novel centrifugal membrane filtration technology for the remediation of liquid mixed waste streams at US Department of Energy (DOE) facilities in support of the DOE Environmental Management (EM) program. The Energy and Environmental Research Center (EERC) has teamed with SpinTek Membrane Systems, Inc., a small business and owner of the novel centrifugal membrane filtration technology, to establish the applicability of the technology to DOE site remediation and the commercial viability of the technology for liquid mixed waste stream remediation. The technology is a uniquely configured process that makes use of ultrafiltration and centrifugal force to separate suspended and dissolved solids from liquid waste streams, producing a filtered water stream and a low-volume contaminated concentrate stream. This technology has the potential for effective and efficient waste volume minimization, the treatment of liquid tank wastes, the remediation of contaminated groundwater plumes, and the treatment of secondary liquid waste streams from other remediation processes, as well as the liquid waste stream generated during decontamination and decommissioning activities

  16. Improved remote HEPA filtration development program

    International Nuclear Information System (INIS)

    Wilson, C.E. III.

    1987-03-01

    This paper presents a summary of the prototype development and hot cell mock-up testing program undertaken to adapt a commercial remote HEPA filter housing for use in the Process Facility Modification Project (PFMP). This program was initiated in response to the project design criteria and documentation that required the air from the hot cell environment to be exhausted through three stages of HEPA filtration. Due to the anticipated quantity of radioactive contamination captured by the first stage of filters, it was determined that the first stage would need to be located in a remotely operated and maintained shielded cell adjoining the primary hot cell areas. Commercially available remote filtration equipment was evaluated and candidate unit was identified, which could be developed into a suitable filter housing. A candidate unit was obtained from Flanders Filters, Inc. and a series of hot cell mock-up tests were identified in the 305 facility at the Hanford site. The results of these tests, and further interaction with the vendor, led to a prototype remote filter housing which satisfied most PFMP criteria and proved to be significantly superior to existing commercial units for remote operation/maintenance

  17. Diatomite releases silica during spirit filtration.

    Science.gov (United States)

    Gómez, J; Gil, M L A; de la Rosa-Fox, N; Alguacil, M

    2014-09-15

    The purpose of this study was to ascertain whether diatomite is an inert filter aid during spirit filtration. Surely, any compound with a negative effect on the spirit composition or the consumer's health could be dissolved. In this study different diatomites were treated with 36% vol. ethanol/water mixtures and the amounts and structures of the extracted compounds were determined. Furthermore, Brandy de Jerez was diatomite- and membrane-filtered at different temperatures and the silicon content was analysed. It was found that up to 0.36% by weight of diatomite dissolved in the aqueous ethanol and amorphous silica, in the form of hollow spherical microparticles, was the most abundant component. Silicon concentrations in Brandy de Jerez increased by up to 163.0% after contact with diatomite and these changes were more marked for calcined diatomite. In contrast, reductions of more than 30% in silicon concentrations were achieved after membrane filtration at low temperatures. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Riverbed Clogging and Sustainability of Riverbank Filtration

    Directory of Open Access Journals (Sweden)

    Thomas Grischek

    2016-12-01

    Full Text Available Clogging refers to a reduction of riverbed hydraulic conductivity. Due to difficulties in determining the thickness of the clogging layer, the leakage coefficient (L is introduced and used to quantify the recoverable portion of bank filtrate. L was determined at several riverbank filtration (RBF sites in field tests and using an analytical solution. Results were compared with data from similar experiments in the early 1970s and 1991–1993. In the 1980s, severe river water pollution in conjunction with high water abstraction led to partly unsaturated conditions beneath the riverbed. A leakage coefficient L of 5 × 10−7 s−1 was determined. After water quality improvement, L increased to 1–1.5 × 10−6 s−1. An alternative, cost and time efficient method is presented to estimate accurate leakage coefficients. The analytical solution is based on groundwater level monitoring data from observation wells next to the river, which can later feed into numerical models. The analytical approach was able to reflect long-term changes as well as seasonal variations. Recommendations for its application are given based on experience.

  19. Silica incorporated membrane for wastewater based filtration

    Science.gov (United States)

    Fernandes, C. S.; Bilad, M. R.; Nordin, N. A. H. M.

    2017-10-01

    Membrane technology has long been applied for waste water treatment industries due to its numerous advantages compared to other conventional processes. However, the biggest challenge in pressure driven membrane process is membrane fouling. Fouling decreases the productivity and efficiency of the filtration, reduces the lifespan of the membrane and reduces the overall efficiency of water treatment processes. In this study, a novel membrane material is developed for water filtration. The developed membrane incorporates silica nanoparticles mainly to improve its structural properties. Membranes with different loadings of silica nanoparticles were applied in this study. The result shows an increase in clean water permeability and filterability of the membrane for treating activated sludge, microalgae solution, secondary effluent and raw sewage as feed. Adding silica into the membrane matrix does not significantly alter contact angle and membrane pore size. We believe that silica acts as an effective pore forming agent that increases the number of pores without significantly altering the pore sizes. A higher number of small pores on the surface of the membrane could reduce membrane fouling because of a low specific loading imposed to individual pores.

  20. Filtration Systems Design for Universal Oils in Agricultural Tractors

    Directory of Open Access Journals (Sweden)

    R. Majdan

    2017-12-01

    Full Text Available Three filtration systems using the tractor hydraulic circuit were proposed and verified during the tractors operation. Using the tractor-implement hydraulic system and filter body with accessories the universally useful filtration systems were designed. The designed filtration systems are the second stage of universal oil filtration whereas the first stage is the standard tractor filter. The decrease in the content of iron reached the values 25.53 %, 32.95 % and 41.55 % and the average decrease in oil contamination characterized by average value of decrease in content of iron, copper and silicium reached values 24.3 %, 24.7 % and 35.53 % in dependence on the filtration system and an oil contamination level. The decrease in contamination level verified the ability of designed filtration systems for agricultural tractors.

  1. A study of dynamic filtration; Um estudo sobre filtracao dinamica

    Energy Technology Data Exchange (ETDEWEB)

    Girao, Joaquim Helder S [PETROBRAS, Natal, RN (Brazil). Distrito de Perfuracao da Bacia Potiguar. Div. de Tecnicas de Perfuracao

    1990-12-31

    The problems that cause cost increase such as: formation damage and borehole swelling or caving lead us to study the filtration of the liquid part of formation drilling fluid. With the aim of comparing static and dynamic filtration rates, we developed a modest dynamic filtration equipment, consisting of a modified API filter, connected to reservoir by means of a positive injection pump. We carried out various tests, and the results were set in charts and tables. Through these, it is possible to notice how the static and dynamic filtration curves come apart for a same pressure value. We also evaluated the effects of circulation speed, starch concentration and counter pressure. This paper does not include calculations or mathematical models accounting for filtrate invasion radii, but it demonstrates, for example, that cleaning circulation will cause lower filtration rates at lower flows. (author) 5 refs., 11 figs., 14 tabs.

  2. A study of dynamic filtration; Um estudo sobre filtracao dinamica

    Energy Technology Data Exchange (ETDEWEB)

    Girao, Joaquim Helder S. [PETROBRAS, Natal, RN (Brazil). Distrito de Perfuracao da Bacia Potiguar. Div. de Tecnicas de Perfuracao

    1989-12-31

    The problems that cause cost increase such as: formation damage and borehole swelling or caving lead us to study the filtration of the liquid part of formation drilling fluid. With the aim of comparing static and dynamic filtration rates, we developed a modest dynamic filtration equipment, consisting of a modified API filter, connected to reservoir by means of a positive injection pump. We carried out various tests, and the results were set in charts and tables. Through these, it is possible to notice how the static and dynamic filtration curves come apart for a same pressure value. We also evaluated the effects of circulation speed, starch concentration and counter pressure. This paper does not include calculations or mathematical models accounting for filtrate invasion radii, but it demonstrates, for example, that cleaning circulation will cause lower filtration rates at lower flows. (author) 5 refs., 11 figs., 14 tabs.

  3. In-Water Hull Cleaning & Filtration System

    Science.gov (United States)

    George, Dan

    2015-04-01

    Dan George R & D Mining Technology LinkedIn GRD Franmarine have received the following prestigious awards in 2014 for their research & development of an in-water hull cleaning and filtration system "The Envirocart: Golden Gecko Award for Environmental Excellence; WA Innovator of the Year - Growth Sector; Department of Fisheries - Excellence in Marine Biosecurity Award - Innovation Category; Lloyd's List Asia Awards - Environmental Award; The Australian Innovation Challenge - Environment, Agriculture and Food Category; and Australian Shipping and Maritime Industry Award - Environmental Transport Award. The Envirocart developed and patented by GRD Franmarine is a revolutionary new fully enclosed capture and containment in-water hull cleaning technology. The Envirocart enables soft Silicon based antifouling paints and coatings containing pesticides such as Copper Oxide to be cleaned in situ using a contactless cleaning method. This fully containerised system is now capable of being deployed to remote locations or directly onto a Dive Support Vessel and is rated to offshore specifications. This is the only known method of in-water hull cleaning that complies with the Department of Agriculture Fisheries and Forestry (DAFF) and Department of Fisheries WA (DoF) Guidelines. The primary underwater cleaning tool is a hydraulically powered hull cleaning unit fitted with rotating discs. The discs can be fitted with conventional brushes for glass or epoxy based coatings or a revolutionary new patented blade system which can remove marine biofouling without damaging the antifouling paint (silicone and copper oxide). Additionally there are a patented range of fully enclosed hand cleaning tools for difficult to access niche areas such as anodes and sea chests, providing an innovative total solution that enables in-water cleaning to be conducted in a manner that causes no biological risk to the environment. In full containment mode or when AIS are present, material is pumped

  4. Vibrating membrane filtration as improved technology for microalgae dewatering

    OpenAIRE

    Nurra, C.; Clavero, E.; Salvadó, J.; Torras, C.

    2014-01-01

    10.1016/j.biortech.2014.01.115 The effect of shear-enhanced filtration by vibratory process in microalgae dewatering is presented in this paper. The aim of this research was to investigate the technical performance and improvement of vibrating membrane filtration compared with conventional tangential cross-flow filtration in microalgae concentration. An industrial-scale available commercial set-up was used. Several membrane materials as polyethersulfone, polyacrylonitrile, etc., and mean ...

  5. Filtration in the Use of Individual Water Purification Devices

    National Research Council Canada - National Science Library

    Lundquist, Arthur; Clarke, Steven; Bettin, William

    2006-01-01

    .... Understanding the ability of filtration to reduce disease-causing microorganisms in water is important in protecting Soldiers, who are considering using this technology, from acute health threats...

  6. Radiotherapy gel dosimetry

    International Nuclear Information System (INIS)

    Baldock, C.

    2002-01-01

    shapes and sizes while sparing normal tissue. The situation is further complicated if the normal tissues are critical organs or are particularly sensitive to radiation. Radiotherapy techniques employed to obtain a closer conformation of the dose distribution to the tumour volume are referred to as conformal radiotherapy techniques. The clinical implementation of conformal therapy has been delayed by limitations in the verification of conformal dose distributions calculated by treatment planning systems prior to the irradiation of the patient and the verification of complex treatments during its delivery to the patient. There are several aspects of conformal therapy that complicate dose verification. To achieve the dose distributions conforming to complex 3D volumes, high dose gradients arise in the treatment volume. Further, overdose or underdose regions can exist when separate radiation fields are used to deliver additional radiation. These aspects require that practical dose measurement (dosimetry) techniques be able to integrate dose over time and easily measure dose distributions in 3D with high spatial resolution. Traditional dosimeters, such as ion chambers, thermoluminescent dosimeters and radiographic film do not fulfil these requirements. Novel gel dosimetry techniques are being developed in which dose distributions can potentially be determined in vitro in 3D using anthropomorphic phantoms to simulate a clinically irradiated situation. As long ago as the 1950's, radiation-induced colour change in dyes was used to investigate radiation doses in gels. It was subsequently shown that radiation induced changes in nuclear magnetic resonance (NMR) relaxation properties of gels infused with conventional Fricke dosimetry solutions could be measured using magnetic resonance imaging (MRI). In Fricke gels, Fe 2+ ions in ferrous sulphate solutions are usually dispersed throughout a gelatin, agarose or PVA matrix. Radiation-induced changes in the dosimeters are considered to

  7. Study on the Fouling Behavior of Polyethylene and Silica Nanoparticles Mixed Matrix Membranes in Filtration of Humic Acid Solution

    Directory of Open Access Journals (Sweden)

    Ali Akbari

    2016-09-01

    Full Text Available Because most contaminants in water create strong interactions with hydrophobic surfaces, there are usually problems such as flux decline and pore blocking in polyethylene (PE membranes due to irreversible adsorption of foulants on their intrinsic hydrophobic surface. Therefore, in this work, attempts were made to improve the properties of PE membranes in terms of water flux and membrane fouling resistance by dispersion of silica nanoparticles (NPs. First, NPs were synthesized by sol-gel method at two concentrations of ammonia (0.5 and 1 mol/L. The synthesized NPs with smaller size were used to fabricate the mixed matrix PE membranes containing 0, 0.5, 1 and 2 wt% NPs. FE-SEM and EDX analyses were employed to evaluate the morphology and structure of the fabricated membranes and confirmed the presence of NPs in the membranes matrix. The results of pure water flux test revealed that the membrane containing 1 wt% NPs displayed the maximum flux of 30 L/m2.h. Furthermore, the performance and fouling behaviors of membranes during filtration of humic acid solution, one of the most important contaminants of water resources, were studied using a classical fouling model. Fouling mechanism analysis showed that for neat and NPs-embedded membranes containing 0.5 and 2 wt% NPs, the best fit of the data was obtained by cake layer formation as well as the intermediate blocking mechanisms. However, the best fit of the experimental data of NPs-embedded membrane containing 1 wt% occurred with only cake layer formation mechanism. The investigation on membrane fouling resistance showed that 1 wt% NPs-embedded membrane displayed 58% maximum flux recovery and 52% reversibility to total fouling ratio, respectively.

  8. Mainstream Smoke Gas Phase Filtration Performance of Adsorption Materials Evaluated With A Puff-by-Puff Multiplex GC-MS Method

    Directory of Open Access Journals (Sweden)

    Xue L

    2014-12-01

    Full Text Available The mainstream smoke filtration performance of activated carbon, silica gel and polymeric aromatic resins for gas-phase components was evaluated using a puff-by-puff multiplex gas chromatography-mass spectrometry (GC-MS analysis method (1. The sample 1R4F Kentucky reference cigarettes were modified by placing the adsorbents in a plug/space/plug filter configuration. Due to differences in surface area and structural characteristics, the adsorbent materials studied showed different levels of filtration activities for the twenty-six constituents monitored. Activated carbon had significant adsorption activity for all the gas-phase smoke constituents observed except ethane and carbon dioxide, while silica gel had significant activities for polar components such as aldehydes, acrolein, ketones, and diacetyl. XAD-16 polyaromatic resins showed varied levels of activity for aromatic compounds, cyclic dienes and ketones.

  9. [Effect of mitomycin C dissolved in a reversible thermosetting gel on outcome of filtering surgery in the rabbit].

    Science.gov (United States)

    Ichien, K; Sawada, A; Yamamoto, T; Kitazawa, Y; Shiraki, R; Yoh, M

    1999-04-01

    Based on our previous report that showed enhanced transfer of mitomycin C to the sclera and the conjunctiva by dissolving the antiproliferative in a reversible thermo-setting gel, we conducted a study to investigate the efficacy of the mitomycin C-gel in the rabbit. We subconjunctivally injected 0.1 ml of the mitomycin C-gel solution containing several amounts of the drug. Trephination was performed in the injected region 24 hours later. Intraocular pressure measurement, and photography and ultrasound biomicroscopic examination of the filtering bleb were done 1, 2, and 4 weeks postoperatively. The gel containing 3.0 micrograms or more mitomycin C significantly enhanced bleb formation in addition to reducing the intraocular pressure. The reversible thermo-setting gel seems to facilitate filtration following glaucoma filtering surgery in the rabbit and deserves further investigation as a new method of mitomycin C application.

  10. Antibacterial Inhibitory Effects of Punica Granatum Gel on Cariogenic Bacteria: An in vitro Study.

    Science.gov (United States)

    Millo, Grazielle; Juntavee, Apa; Ratanathongkam, Ariya; Nualkaew, Natsajee; Peerapattana, Jomjai; Chatchiwiwattana, Supaporn

    2017-01-01

    This study evaluated the in vitro antibacterial effects of the formulated Punica granatum (PG) gel against Streptococcus mutans, Streptococcus sanguinis, and Lactobacillus casei. The PG extract was dissolved in water at 500 mg/mL. High performance liquid chromatography (HPLC) was used for identification and quantification of chemical marker punicalagin. Minimum bactericidal concentration (MBC) and time-kill assay (TKA) were investigated. Antibacterial activities of the formulated PG gel, 2% chlorhexidine (CHX) gel and blank gel were tested by measuring the zones of inhibition through agar well diffusion method. The HPLC results showed presence of punicalagin at 2023.58 ± 25.29 pg/mL in the aqueous PG extract and at 0.234% (w/w) in the formulated PG gel. The MBC for S. mutans, S. Sanguinis, and L. casei were 250, 125, and 500 mg/mL respectively. The TKA of 500 mg/mL aqueous PG extract showed total inhibition of S. mutans, S. Sanguinis, and L. casei at 6, 1, and 24 hours contact time respectively. Agar well diffusion revealed that for S. mutans, CHX gel > PG gel > blank gel; for S. sanguinis, CHX gel = PG gel > blank gel; for L. casei, CHX gel > PG gel = blank gel. Comparison of the PG gel potency showed that S. sanguinis = S. mutans > L. casei. The PG gel equivalent to 0.234% punicalagin (w/w) inhibited S. mutans and S. sanguinis but not L. casei within 24 hours incubation period and has the potential to be used for caries prevention. Millo G, Juntavee A, Ratanathongkam A, Nualkaew N, Peerapattana J, Chatchiwiwattana S. Antibacterial Inhibitory Effects of Punica Granatum Gel on Cariogenic Bacteria: An in vitro Study. Int J Clin Pediatr Dent 2017;10(2):152-157.

  11. Filtration of sodium-fire aerosols

    International Nuclear Information System (INIS)

    Alexas, A.; Jordan, S.; Lindner, W.

    1979-01-01

    Different filter devices have been developed and tested with respect to their use in the off-gas system of liquid-metal fast breeder reactors to prevent the escape of sodium-fire aerosols that might be formed in case of an accident. The testing results have shown that the use of a multilayer sand bed filter is still the best method to filter limited amounts of sodium-fire aerosols over a long operating time. Efficiencies on the order of 99.98 and 98.8% were reached for loading capacities of 500 and 1000 g/m 2 , respectively. Unlimited amounts of sodium-fire aerosols can be filtered by wet scrubbers with an efficiency of 70% per scrubber stage. Fiberglas filters connot be used for the filtration of sodium-fire aerosols over a long operating time because the filter material can be destroyed after several days of operating

  12. Experiments on high efficiency aerosol filtration

    International Nuclear Information System (INIS)

    Mazzini, M.; Cuccuru, A.; Kunz, P.

    1977-01-01

    Research on high efficiency aerosol filtration by the Nuclear Engineering Institute of Pisa University and by CAMEN in collaboration with CNEN is outlined. HEPA filter efficiency was studied as a function of the type and size of the test aerosol, and as a function of flowrate (+-50% of the nominal value), air temperature (up to 70 0 C), relative humidity (up to 100%), and durability in a corrosive atmosphere (up to 140 hours in NaCl mist). In the selected experimental conditions these influences were appreciable but are not sufficient to be significant in industrial HEPA filter applications. Planned future research is outlined: measurement of the efficiency of two HEPA filters in series using a fixed particle size; dependence of the efficiency on air, temperatures up to 300-500 0 C; performance when subject to smoke from burning organic materials (natural rubber, neoprene, miscellaneous plastics). Such studies are relevant to possible accidental fires in a plutonium laboratory

  13. High transparent shape memory gel

    Science.gov (United States)

    Gong, Jin; Arai, Masanori; Kabir, M. H.; Makino, Masato; Furukawa, Hidemitsu

    2014-03-01

    Gels are a new material having three-dimensional network structures of macromolecules. They possess excellent properties as swellability, high permeability and biocompatibility, and have been applied in various fields of daily life, food, medicine, architecture, and chemistry. In this study, we tried to prepare new multi-functional and high-strength gels by using Meso-Decoration (Meso-Deco), one new method of structure design at intermediate mesoscale. High-performance rigid-rod aromatic polymorphic crystals, and the functional groups of thermoreversible Diels-Alder reaction were introduced into soft gels as crosslinkable pendent chains. The functionalization and strengthening of gels can be realized by meso-decorating the gels' structure using high-performance polymorphic crystals and thermoreversible pendent chains. New gels with good mechanical properties, novel optical properties and thermal properties are expected to be developed.

  14. Fluoride removal from water by nano filtration

    International Nuclear Information System (INIS)

    Bejaoui, Imen; Mnif, Amine; Hamrouni, Bechir

    2009-01-01

    As any oligo element, fluoride is necessary and beneficial for human health to low concentrations, but an excess amount of fluoride ions in drinking water has been known to cause undesirable effects, especially tooth and bones fluoro sis. The maximum acceptable concentration of fluoride in drinking water was fixed by the World Health Organization according to the climate in the range of 1 mg.L -1 to 1,2 mg.L -1 . Many methods have been used to remove fluoride from water such as precipitation, adsorption, electrocoagulation and membrane processes. Technologies using membrane processes are being used in many applications, particularly for brackish water desalination. Nano filtration seems to be the best process for a good selective defluorination of fluorinated waters. The main objective of this work was to investigate the retention of fluoride anions by nano filtration. The first part of this study deals with the characterisation of the NF HL2514TF membrane. The influence of various experimental parameters such as initial fluoride content, feed pressure, permeate flux, ionic strength, type of cation associated to fluoride and pH were studied in the second part. Results show that the retention order for the salts tested was TR(Na 2 SO 4 ) > TR(CaCl 2 ) > TR(NaCl), showing a retention sequence inversely proportional to the salt diffusion coefficients in water. It was also shown that charge effects could not be neglected, and a titration experiments confirmed that the NF membrane carry a surplus of negatively charged groups. Fluoride retention exceeds 60 pour cent, and increases with increasing concentration, where the rejection mechanism is related to the dielectric effects. Speigler-Kedem model was applied to experimental results in the aim to determine phenomenological parametersσand P s respectively, the reflexion coefficient of the membrane and the solute permeability of ions. The convective and diffusive parts of the mass transfer were quantified with

  15. Thoria sol-gel processes

    International Nuclear Information System (INIS)

    Matthews, R.B.

    1978-10-01

    Alternate fuel fabrication techniques are being developed at WNRE as part of the thorium fuel cycle program. The sol-gel techniques are attractive and this report assembles and summarizes information relating to thoria sol-gel fuels. Some background information on the behaviour and advantages of sol-gel fuel forms is presented, followed by a review of relevant colloid chemistry and an explanation of the fundamental steps of sol-gel processes. Finally, several variants to the basic process are reviewed and evaluated. (author)

  16. Silver nitrate based gel dosimeter

    International Nuclear Information System (INIS)

    Titus, D; Samuel, E J J; Srinivasan, K; Roopan, S M; Madhu, C S

    2017-01-01

    A new radiochromic gel dosimeter based on silver nitrate and a normoxic gel dosimeter was investigated using UV-Visible spectrophotometry in the clinical dose range. Gamma radiation induced the synthesis of silver nanoparticles in the gel and is confirmed from the UV-Visible spectrum which shows an absorbance peak at around 450 nm. The dose response function of the dosimeter is found to be linear upto12Gy. In addition, the gel samples were found to be stable which were kept under refrigeration. (paper)

  17. Gel polymer electrolytes for batteries

    Science.gov (United States)

    Balsara, Nitash Pervez; Eitouni, Hany Basam; Gur, Ilan; Singh, Mohit; Hudson, William

    2014-11-18

    Nanostructured gel polymer electrolytes that have both high ionic conductivity and high mechanical strength are disclosed. The electrolytes have at least two domains--one domain contains an ionically-conductive gel polymer and the other domain contains a rigid polymer that provides structure for the electrolyte. The domains are formed by block copolymers. The first block provides a polymer matrix that may or may not be conductive on by itself, but that can soak up a liquid electrolyte, thereby making a gel. An exemplary nanostructured gel polymer electrolyte has an ionic conductivity of at least 1.times.10.sup.-4 S cm.sup.-1 at 25.degree. C.

  18. Purification of contaminated water by filtration through porous glass

    Science.gov (United States)

    Wydeven, T.; Leban, M. I.

    1972-01-01

    Method for purifying water that is contaminated with mineral salts and soluble organic compounds is described. Method consists of high pressure filtration of contaminated water through stabilized porous glass membranes. Procedure for conducting filtration is described. Types of materials by percentage amounts removed from the water are identified.

  19. 40 CFR 141.171 - Criteria for avoiding filtration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Criteria for avoiding filtration. 141.171 Section 141.171 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced Filtration and Disinfection...

  20. Scaling and particulate fouling in membrane filtration systems

    NARCIS (Netherlands)

    Boerlage, S.F.E.

    2001-01-01

    In the last decade, pressure driven membrane filtration processes; reverse osmosis, nano, ultra and micro-filtration have undergone steady growth. Drivers for this growth include desalination to combat water scarcity and the removal of various material from water to comply with increasingly

  1. Filter aids influence on pressure drop across a filtration system

    Science.gov (United States)

    Hajar, S.; Rashid, M.; Nurnadia, A.; Ammar, M. R.; Hasfalina, C. M.

    2017-06-01

    Filter aids is commonly used to reduce pressure drop across air filtration system as it helps to increase the efficiency of filtration of accumulated filter cake. Filtration velocity is one of the main parameters that affect the performance of filter aids material. In this study, a formulated filter aids consisting of PreKot™ and activated carbon mixture (designated as PrekotAC) was tested on PTFE filter media under various filtration velocities of 5, 6, and 8 m/min at a constant material loading of 0.2 mg/mm2. Results showed that pressure drop is highly influenced by filtration velocity where higher filtration velocity leads to a higher pressure drop across the filter cake. It was found that PrekotAC performed better in terms of reducing the pressure drop across the filter cake even at the highest filtration velocity. The diversity in different particle size distribution of non-uniform particle size in the formulated PrekotAC mixture presents a higher permeability causes a lower pressure drop across the accumulated filter cake. The finding suggests that PrekotAC is a promising filter aids material that helps reducing the pressure drop across fabric filtration system.

  2. Dynamic optimization of dead-end membrane filtration

    NARCIS (Netherlands)

    Blankert, B.; Betlem, Bernardus H.L.; Roffel, B.; Marquardt, Wolfgang; Pantelides, Costas

    2006-01-01

    An operating strategy aimed at minimizing the energy consumption during the filtration phase of dead-end membrane filtration has been formulated. A method allowing fast calculation of trajectories is used to allow incorporation in a hierarchical optimization scheme. The optimal trajectory can be

  3. Rotating Ceramic Water Filter Discs System for Water Filtration

    Directory of Open Access Journals (Sweden)

    Riyadh Z. Al Zubaidy

    2017-04-01

    Full Text Available This work aimed to design, construct and operate a new laboratory scale water filtration system. This system was used to examine the efficiency of two ceramic filter discs as a medium for water filtration. These filters were made from two different ceramic mixtures of local red clay, sawdust, and water. The filtration system was designed with two rotating interfered modules of these filters. Rotating these modules generates shear force between water and the surfaces of filter discs of the filtration modules that works to reduce thickness of layer of rejected materials on the filters surfaces. Each module consists of seven filtration units and each unit consists of two ceramic filter discs. The average measured hydraulic conductivity of the first module was 13.7mm/day and that for the second module was 50mm/day. Results showed that the water filtration system can be operated continuously with a constant flow rate and the filtration process was controlled by a skin thin layer of rejected materials. The ceramic water filters of both filtration modules have high removal efficiency of total suspended solids up to 100% and of turbidity up to 99.94%.

  4. Life Support Filtration System Trade Study for Deep Space Missions

    Science.gov (United States)

    Agui, Juan H.; Perry, Jay L.

    2017-01-01

    The National Aeronautics and Space Administrations (NASA) technical developments for highly reliable life support systems aim to maximize the viability of long duration deep space missions. Among the life support system functions, airborne particulate matter filtration is a significant driver of launch mass because of the large geometry required to provide adequate filtration performance and because of the number of replacement filters needed to a sustain a mission. A trade analysis incorporating various launch, operational and maintenance parameters was conducted to investigate the trade-offs between the various particulate matter filtration configurations. In addition to typical launch parameters such as mass, volume and power, the amount of crew time dedicated to system maintenance becomes an increasingly crucial factor for long duration missions. The trade analysis evaluated these parameters for conventional particulate matter filtration technologies and a new multi-stage particulate matter filtration system under development by NASAs Glenn Research Center. The multi-stage filtration system features modular components that allow for physical configuration flexibility. Specifically, the filtration system components can be configured in distributed, centralized, and hybrid physical layouts that can result in considerable mass savings compared to conventional particulate matter filtration technologies. The trade analysis results are presented and implications for future transit and surface missions are discussed.

  5. Vibrating membrane filtration as improved technology for microalgae dewatering.

    Science.gov (United States)

    Nurra, Claudia; Clavero, Ester; Salvadó, Joan; Torras, Carles

    2014-04-01

    The effect of shear-enhanced filtration by vibratory process in microalgae dewatering is presented in this paper. The aim of this research was to investigate the technical performance and improvement of vibrating membrane filtration compared with conventional tangential cross-flow filtration in microalgae concentration. An industrial-scale available commercial set-up was used. Several membrane materials as polyethersulfone, polyacrylonitrile, etc., and mean pore sizes (from 7000Da to 0.2μm) were tested and compared in both filtration set-ups. Experiments were carried-out with Nannochloropsis gaditana and Phaeodactylum tricornutum microalgae. It has been demonstrated that, even if the choice of the membrane depends on its cut-off, its material and the type of microalgae filtrated, dynamic filtration is always the best technology over a conventional one. If with conventional filtration permeability values were in the vicinity of 10L/h/m(2)/bar in steady state phase, with dynamic filtration these values increased to 30L/h/m(2)/bar or more. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Filtration behaviors of rod-shaped bacterial broths in unsteady-state phase of cross-flow filtration

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, T.; Usui, K.; Koda, K.; Nakanishi, K. [Okayama University, Okayama (Japan). Faculty of Engineering

    1996-12-20

    Filtration behaviors in the unsteady-state phase of crossflow filtration of broths of Bacillus subtilis, Escherichia coli, and Lactobacillus delbrueckii, which are rod-shaped, were studied from the viewpoint of the changes in the specific resistance and in the structure of the microbial cake formed on the membrane surface. The permeation flux followed the cake filtration law at the initial stage of the crossflow filtration of the broths of B. subtilis and E. coli, where the cells deposited randomly on the membrane. In the case of the crossflow filtration of a L. delbrueckii broth, the period of random deposition was shorter. The specific resistance for the cake formed at the initial stage agreed with that measured in dead-end filtration. Then, the specific resistance started to increase in comparison with that measured in dead-end filtration due to shear-induced arrangement of the cells. The extent of the increase in specific resistance became higher and the time taken to start the cell arrangement became shorter with increasing circulation flow rate. The increase in specific resistance due to the shear-induced arrangement was more appreciable in the crossflow filtration of the broth of L. delbrueckii than that of B. subtilis and E. coli. The average permeation flux was increased considerably by applying periodical backwashing with appropriate time intervals. The permeation flux was well predicted by the cake filtration law, since the cells deposited in a way similar to that for dead-end filtration during a sufficiently short period of crossflow filtration in a backwashing mode. 21 refs., 11 figs.

  7. Modelling technological process of ion-exchange filtration of fluids in porous media

    Science.gov (United States)

    Ravshanov, N.; Saidov, U. M.

    2018-05-01

    Solution of an actual problem related to the process of filtration and dehydration of liquid and ionic solutions from gel particles and heavy ionic compounds is considered in the paper. This technological process is realized during the preparation and cleaning of chemical solutions, drinking water, pharmaceuticals, liquid fuels, products for public use, etc. For the analysis, research, determination of the main parameters of the technological process and operating modes of filter units and for support in managerial decision-making, a mathematical model is developed. Using the developed model, a series of computational experiments on a computer is carried out. The results of numerical calculations are illustrated in the form of graphs. Based on the analysis of numerical experiments, the conclusions are formulated that serve as the basis for making appropriate managerial decisions.

  8. Zebra mussel filtration and its potential uses in industrial water treatment.

    Science.gov (United States)

    Elliott, Paul; Aldridge, David C; Moggridge, Geoff D

    2008-03-01

    The zebra mussel (Dreissena polymorpha) is a notorious freshwater biofouling pest, and populations of the species can alter aquatic environments through their substantial filtration capabilities. Despite the ecological importance of zebra mussel filtration, many predictions of their large-scale effects on ecosystems rely on extrapolations from filtration rates obtained in static laboratory experiments, not accounting for natural mussel densities, boundary layer effects, flow rates or elevated algal concentrations. This study used large-scale industrial flume trials to investigate the influence of these factors on zebra mussel filtration and proposes some novel industrial applications of these findings. The flume trials revealed some of the highest zebra mussel clearance rates found to date, up to 574+/-20mlh(-1)g(-1) of wet tissue mass. Under low algal concentrations, chlorophyll a removal by zebra mussels was not proportional to mussel density, indicating that field rates of zebra mussel grazing may be much lower than previous studies have predicted. Increasing ambient velocities up to 100mls(-1) ( approximately 4cms(-1)) led to increased clearance rates by zebra mussels, possibly due to the replenishment of locally depleted resources, but higher velocities of 300mls(-1) (12cms(-1)) did not lead to further significant increases in clearance rate. When additional algal cultures were dosed into the flumes, chlorophyll a removal increased approximately logarithmically with zebra mussel density and there were no differences in the clearance of three different species of alga: Ankyra judayi, Pandorina morum and Cyclotella meneghinia. Some novel industrial uses of these zebra mussel filtration studies are proposed, such as: (1) helping to inform models that predict the large-scale grazing effects of the mussels, (2) allowing estimates of zebra mussel densities in industrial pipelines, and (3) constructing large-scale biofilters for use in water clarification.

  9. Strand Plasticity Governs Fatigue in Colloidal Gels

    Science.gov (United States)

    van Doorn, Jan Maarten; Verweij, Joanne E.; Sprakel, Joris; van der Gucht, Jasper

    2018-05-01

    The repeated loading of a solid leads to microstructural damage that ultimately results in catastrophic material failure. While posing a major threat to the stability of virtually all materials, the microscopic origins of fatigue, especially for soft solids, remain elusive. Here we explore fatigue in colloidal gels as prototypical inhomogeneous soft solids by combining experiments and computer simulations. Our results reveal how mechanical loading leads to irreversible strand stretching, which builds slack into the network that softens the solid at small strains and causes strain hardening at larger deformations. We thus find that microscopic plasticity governs fatigue at much larger scales. This gives rise to a new picture of fatigue in soft thermal solids and calls for new theoretical descriptions of soft gel mechanics in which local plasticity is taken into account.

  10. Rheology and structure of milk protein gels

    NARCIS (Netherlands)

    Vliet, van T.; Lakemond, C.M.M.; Visschers, R.W.

    2004-01-01

    Recent studies on gel formation and rheology of milk gels are reviewed. A distinction is made between gels formed by aggregated casein, gels of `pure` whey proteins and gels in which both casein and whey proteins contribute to their properties. For casein' whey protein mixtures, it has been shown

  11. Etodolac Containing Topical Niosomal Gel: Formulation Development and Evaluation

    Directory of Open Access Journals (Sweden)

    Gyati Shilakari Asthana

    2016-01-01

    Full Text Available The present study aimed to investigate the delivery potential of Etodolac (ETD containing topical niosomal gel. Niosomal formulations were prepared by thin film hydration method at various ratios of cholesterol and Span 60 and were evaluated with respect to particle size, shape, entrapment efficiency, and in vitro characteristics. Dicetyl phosphate (DCP was also added in the niosomal formulation. Mean particle size of niosomal formulation was found to be in the range of 2 μm to 4 μm. Niosomal formulation N2 (1 : 1 ratio of cholesterol and surfactant displayed good entrapment efficiency (96.72%. TEM analyses showed that niosomal formulation was spherical in shape. Niosomal formulation (N2 displayed high percentage of drug release after 24 h (94.91 at (1 : 1 ratio of cholesterol : surfactant. Further selected niosomal formulation was used to formulate topical gel and was characterized with respect to its various parameters such as pH, viscosity, spreadability, ex vivo study, and in vivo potential permeation. Ex vivo study showed that niosomal gel possessed better skin permeation study than the plain topical gel. Further in vivo study revealed good inhibition of inflammation in case of topical niosomal gel than plain gel and niosomal formulation. The present study suggested that topical niosomal gel formulations provide sustained and prolonged delivery of drug.

  12. Pecan drying with silica gel

    Energy Technology Data Exchange (ETDEWEB)

    Ghate, S.R.; Chhinnan, M.S.

    1983-07-01

    High moisture in-shell pecans were dried by keeping them in direct and indirect contact with silica gel to investigate their drying characteristics. In-shell pecans were also dried with ambient air from a controlled environment chamber and with air dehumidified by silica gel. Direct contact and dehumidified air drying seemed feasible approaches.

  13. Nanocrystal/sol-gel nanocomposites

    Science.gov (United States)

    Petruska, Melissa A [Los Alamos, NM; Klimov, Victor L [Los Alamos, NM

    2007-06-05

    The present invention is directed to solid composites including colloidal nanocrystals within a sol-gel host or matrix and to processes of forming such solid composites. The present invention is further directed to alcohol soluble colloidal nanocrystals useful in formation of sol-gel based solid composites.

  14. Industrial Application of Open Pore Ceramic Foam for Molten Metal Filtration

    Science.gov (United States)

    Gauckler, L. J.; Waeber, M. M.; Conti, C.; Jacob-Dulière, M.

    Ceramic foam filters were used for industrial filtration of aluminum. Results are compared with laboratory experiments which are in good agreement with trajectory analyses of deep bed filtration for the early stage of filtration.

  15. Estimating Glomerular Filtration Rate in Older People

    Directory of Open Access Journals (Sweden)

    Sabrina Garasto

    2014-01-01

    Full Text Available We aimed at reviewing age-related changes in kidney structure and function, methods for estimating kidney function, and impact of reduced kidney function on geriatric outcomes, as well as the reliability and applicability of equations for estimating glomerular filtration rate (eGFR in older patients. CKD is associated with different comorbidities and adverse outcomes such as disability and premature death in older populations. Creatinine clearance and other methods for estimating kidney function are not easy to apply in older subjects. Thus, an accurate and reliable method for calculating eGFR would be highly desirable for early detection and management of CKD in this vulnerable population. Equations based on serum creatinine, age, race, and gender have been widely used. However, these equations have their own limitations, and no equation seems better than the other ones in older people. New equations specifically developed for use in older populations, especially those based on serum cystatin C, hold promises. However, further studies are needed to definitely accept them as the reference method to estimate kidney function in older patients in the clinical setting.

  16. Filtration characteristics of porous silicon carbide media

    International Nuclear Information System (INIS)

    Ahn, Byung Gil; Seo, Yong Chil; Yim, Sung Paal; Kim, Joon Hyung

    1991-01-01

    The characteristics of a filter such as clean filter pressure drop, filtering performance and filter drag variation with dust loading have been studied with fabricated SiC filter specimens in the laboratory and commercial ceramic filters. Several theoretical equations have been modified and applied to investigate such characteristics. To estimate the pressure drop of clean gas flow through a cylindrical porous filter, Forchheimer equation, which contains the terms of permeability and turbulent factor at a high velocity of gas, has been modified and tested with experimental data. The filtering efficiency was found to be above 99.9% and the penetration of dust decreased exponentially with dust loading. The pressure drop during filtration was measured and showed to increase exponentially with dust loading in the beginning because particles were intercepted and a cake layer was formed by structural properties of a filter. And then it increased in proportion as the cake layer thickened. The effect of dust deposition on the pressure drop could be explained theoretically using several characteristic parameters relevant to dust size, structure of filters and cake layer formation

  17. Crosslinked polytriazole membranes for organophilic filtration

    KAUST Repository

    Chisca, Stefan

    2016-12-30

    We report the preparation of crosslinked membranes for organophilic filtration, by reacting a new polytriazole with free OH groups, using non-toxic poly (ethylene glycol) diglycidyl ether (PEGDE). The OH-functionalized polymer was obtained by converting the oxadiazole to triazole rings with high yield (98%). The maximum degree of crosslinking is achieved after 6 h of reaction. The crosslinked polytriazole membranes are stable in a wide range of organic solvents and show high creep recovery, indicating the robustness of crosslinked membranes. The influence of different casting solutions and different crosslinking time on the membrane morphology and membrane performance was investigated. The membranes performance was studied in dimethylformamide (DMF) and (tetrahydrofuran) THF. We achieved a permeance for THF of 49 L m−2 h−1 bar−1 for membranes with molecular weight cut off (MWCO) of 7 kg mol−1 and a permeance for THF of 17.5 L m−2 h−1 bar−1 for membranes with MWCO of 3 kg mol−1. Our data indicate that by using the new polytriazole is possible to adjust the pore dimensions of the membranes to have a MWCO, which covers ultra- and nanofiltration range.

  18. Macular thickness after glaucoma filtration surgery.

    Science.gov (United States)

    Sesar, Antonio; Cavar, Ivan; Sesar, Anita Pusić; Geber, Mia Zorić; Sesar, Irena; Laus, Katia Novak; Vatavuk, Zoran; Mandić, Zdravko

    2013-09-01

    The aim of present study was to analyze early postoperative changes in the macular area using optical coherence tomography (OCT) after uncomplicated glaucoma filtration surgery. This prospective study included 32 patients (34 eyes) with open-angle glaucoma, which underwent trabeculectomy with or without use of mitomycin C. Exclusion criteria were macular edema, uveitis, age-related macular degeneration, blurred optical media, secondary glaucoma and angle-closure glaucoma. All standard clinical examinations were made before surgery, at the 2nd day, 1 week and 1 month after surgery. Tomography of the macula was performed during every examination using Cirrus HD OCT for the analysis of central subfield thickness. Results show that thickening of the macula was slightly higher 1 week and 1 month after operation in comparison with baseline end 2nd day postoperativelly. There was no significant difference in the change of macular thickness in patients who have used topical prostaglandins compared with those who have used other topical medications. Also, there was no difference in macular changes between patients treated with or without mitomycin C. In conclusion, we found a slight subclinical increase in macular thickness after uncomplicated trabeculectomy, for which we considered that was the result in reduction of intraocular pressure after glaucoma surgery. Macular thickening after glaucoma filtering surgery could be a physiological reaction to the stress of the retina caused by a sudden reduction of intraocular pressure and it is the consequence of altered relationship between capillary pressure and interstitial fluid pressure.

  19. CRNL research reactor retrofit Emergency Filtration System

    International Nuclear Information System (INIS)

    Philippi, H.M.

    1990-01-01

    This paper presents a brief history of NRX and NRU research reactor effluent air treatment systems before describing the selection and design of an appropriate retrofit Emergency Filtration System (EFS) to serve these reactors and the future MX-10 isotope production reactor. The conceptual design of the EFS began in 1984. A standby concrete shielding filter-adsorber system, sized to serve the reactor with the largest exhaust flow, was selected. The standby system, bypassed under normal operating conditions, is equipped with normal exhaust stream shutoff and diversion valves to be activated manually when an emergency is anticipated, or automatically when emergency levels of gamma radiation are detected in the exhaust stream. The first phase of the EFS installation, that is the construction of the EFS and the connection of NRU to the system, was completed in 1987. The second phase of construction, which includes the connection of NRX and provisions for the future connection of MX-10, is to be completed in 1990

  20. Filtration of submicrometer particles by pelagic tunicates.

    Science.gov (United States)

    Sutherland, Kelly R; Madin, Laurence P; Stocker, Roman

    2010-08-24

    Salps are common in oceanic waters and have higher per-individual filtration rates than any other zooplankton filter feeder. Although salps are centimeters in length, feeding via particle capture occurs on a fine, mucous mesh (fiber diameter d approximately 0.1 microm) at low velocity (U = 1.6 +/- 0.6 cmxs(-1), mean +/- SD) and is thus a low Reynolds-number (Re approximately 10(-3)) process. In contrast to the current view that particle encounter is dictated by simple sieving of particles larger than the mesh spacing, a low-Re mathematical model of encounter rates by the salp feeding apparatus for realistic oceanic particle-size distributions shows that submicron particles, due to their higher abundances, are encountered at higher rates (particles per time) than larger particles. Data from feeding experiments with 0.5-, 1-, and 3-microm diameter polystyrene spheres corroborate these findings. Although particles larger than 1 microm (e.g., flagellates, small diatoms) represent a larger carbon pool, smaller particles in the 0.1- to 1-microm range (e.g., bacteria, Prochlorococcus) may be more quickly digestible because they present more surface area, and we find that particles smaller than the mesh size (1.4 microm) can fully satisfy salp energetic needs. Furthermore, by packaging submicrometer particles into rapidly sinking fecal pellets, pelagic tunicates can substantially change particle-size spectra and increase downward fluxes in the ocean.

  1. Crosslinked polytriazole membranes for organophilic filtration

    KAUST Repository

    Chisca, Stefan; Falca, Gheorghe; Musteata, Valentina-Elena; Boi, Cristiana; Nunes, Suzana Pereira

    2016-01-01

    We report the preparation of crosslinked membranes for organophilic filtration, by reacting a new polytriazole with free OH groups, using non-toxic poly (ethylene glycol) diglycidyl ether (PEGDE). The OH-functionalized polymer was obtained by converting the oxadiazole to triazole rings with high yield (98%). The maximum degree of crosslinking is achieved after 6 h of reaction. The crosslinked polytriazole membranes are stable in a wide range of organic solvents and show high creep recovery, indicating the robustness of crosslinked membranes. The influence of different casting solutions and different crosslinking time on the membrane morphology and membrane performance was investigated. The membranes performance was studied in dimethylformamide (DMF) and (tetrahydrofuran) THF. We achieved a permeance for THF of 49 L m−2 h−1 bar−1 for membranes with molecular weight cut off (MWCO) of 7 kg mol−1 and a permeance for THF of 17.5 L m−2 h−1 bar−1 for membranes with MWCO of 3 kg mol−1. Our data indicate that by using the new polytriazole is possible to adjust the pore dimensions of the membranes to have a MWCO, which covers ultra- and nanofiltration range.

  2. Additive Difference Schemes for Filtration Problems in Multilayer Systems

    CERN Document Server

    Ayrjan, E A; Pavlush, M; Fedorov, A V

    2000-01-01

    In the present paper difference schemes for solution of the plane filtration problem in multilayer systems are analyzed within the framework of difference schemes general theory. Attention is paid to splitting the schemes on physical processes of filtration along water-carring layers and vertical motion between layers. Some absolutely stable additive difference schemes are obtained the realization of which needs no software modification. Parallel algorithm connected with the solving of the filtration problem in every water-carring layer on a single processor is constructed. Program realization on the multi-processor system SPP2000 at JINR is discussed.

  3. Chemical Gel for Surface Decontamination

    International Nuclear Information System (INIS)

    Jung, Chong Hun; Moon, J. K.; Won, H. J.; Lee, K. W.; Kim, C. K.

    2010-01-01

    Many chemical decontamination processes operate by immersing components in aggressive chemical solutions. In these applications chemical decontamination technique produce large amounts of radioactive liquid waste. Therefore it is necessary to develop processes using chemical gels instead of chemical solutions, to avoid the well-known disadvantages of chemical decontamination techniques while retaining their high efficiency. Chemical gels decontamination process consists of applying the gel by spraying it onto the surface of large area components (floors, walls, etc) to be decontaminated. The gel adheres to any vertical or complex surface due to their thixotropic properties and operates by dissolving the radioactive deposit, along with a thin layer of the gel support, so that the radioactivity trapped at the surface can be removed. Important aspects of the gels are that small quantities can be used and they show thixitropic properties : liquid during spraying, and solid when stationary, allowing for strong adherence to surfaces. This work investigates the decontamination behaviors of organic-based chemical gel for SS 304 metallic surfaces contaminated with radioactive materials

  4. Denaturing gradient gel electrophoresis

    International Nuclear Information System (INIS)

    Kocherginskaya, S.A.; Cann, I.K.O.; Mackie, R.I.

    2005-01-01

    It is worthwhile considering that only some 30 species make up the bulk of the bacterial population in human faeces at any one time based on the classical cultivation-based approach. The situation in the rumen is similar. Thus, it is practical to focus on specific groups of interest within the complex community. These may be the predominant or the most active species, specific physiological groups or readily identifiable (genetic) clusters of phylogenetically related organisms. Several 16S rDNA fingerprinting techniques can be invaluable for selecting and monitoring sequences or phylogenetic groups of interest and are described below. Over the past few decades, considerable attention was focussed on the identification of pure cultures of microbes on the basis of genetic polymorphisms of DNA encoding rRNA such as ribotyping, amplified fragment length polymorphism and randomly amplified polymorphic DNA. However, many of these methods require prior cultivation and are less suitable for use in analysis of complex mixed populations although important in describing cultivated microbial diversity in molecular terms. Much less attention was given to molecular characterization of complex communities. In particular, research into diversity and community structure over time has been revolutionized by the advent of molecular fingerprinting techniques for complex communities. Denaturing or temperature gradient gel electrophoresis (DGGE/TGGE) methods have been successfully applied to the analysis of human, pig, cattle, dog and rodent intestinal populations

  5. Development of new cleanup method of polychlorinated dibenzo-p-dioxins/dibenzofurans in fish by freezing-lipid filtration

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Yun Gyong [Hazardous Substance Research Team, Korea Basic Science Institute, Seoul 136-701 (Korea, Republic of); Seo, Jungju [Hazardous Substance Research Team, Korea Basic Science Institute, Seoul 136-701 (Korea, Republic of); Shin, Jeoung Hwa [Hazardous Substance Research Team, Korea Basic Science Institute, Seoul 136-701 (Korea, Republic of); Khim, Jeehyeong [Department of Civil Environment Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Hong, Jongki [College of Pharmacy, Kyung Hee University, Hoegi-Dong, Dongdaemoon-Ku, Seoul 130-701 (Korea, Republic of)]. E-mail: jhong@khu.ac.kr

    2006-08-18

    Freezing-lipid filtration as a new method has been developed for the rapid determination of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDDs/Fs) in biological samples. This method can effectively reduce the time of sample pretreatment, labor and amount of solvents compared with conventional methods. By freezing-lipid filtration procedure, about 90% of lipids in extract could be removed without any significant loss of PCDD/Fs. For further cleanup of extracts after freezing-lipid filtration, automatic parallel LC columns including silica gel, alumina and carbon columns were applied. During automatic parallel LC columns cleanup, most of co-extracted interferences such as residue lipids and fatty acids could be eliminated and dioxins could be separated from many other dioxin-like congeners such as polychlorinated biphenyls by this procedure. The extracts after cleanup were analyzed by high-resolution gas chromatography (HRGC)/high-resolution mass spectrometry (HRMS) using an isotope dilution method. The average recoveries and relative standard deviation (R.S.D.) of 17 native congeners in the spiked fish samples at 8-80 pg/g (n = 3) were ranged between 85.3 and 117.2% and 5.7-20.3%, respectively.

  6. Development of new cleanup method of polychlorinated dibenzo-p-dioxins/dibenzofurans in fish by freezing-lipid filtration

    International Nuclear Information System (INIS)

    Ahn, Yun Gyong; Seo, Jungju; Shin, Jeoung Hwa; Khim, Jeehyeong; Hong, Jongki

    2006-01-01

    Freezing-lipid filtration as a new method has been developed for the rapid determination of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDDs/Fs) in biological samples. This method can effectively reduce the time of sample pretreatment, labor and amount of solvents compared with conventional methods. By freezing-lipid filtration procedure, about 90% of lipids in extract could be removed without any significant loss of PCDD/Fs. For further cleanup of extracts after freezing-lipid filtration, automatic parallel LC columns including silica gel, alumina and carbon columns were applied. During automatic parallel LC columns cleanup, most of co-extracted interferences such as residue lipids and fatty acids could be eliminated and dioxins could be separated from many other dioxin-like congeners such as polychlorinated biphenyls by this procedure. The extracts after cleanup were analyzed by high-resolution gas chromatography (HRGC)/high-resolution mass spectrometry (HRMS) using an isotope dilution method. The average recoveries and relative standard deviation (R.S.D.) of 17 native congeners in the spiked fish samples at 8-80 pg/g (n = 3) were ranged between 85.3 and 117.2% and 5.7-20.3%, respectively

  7. Water quality and treatment of river bank filtrate

    NARCIS (Netherlands)

    De Vet, W.W.J.M.; Van Genuchten, C.C.A.; Van Loosdrecht, M.C.M.; Van Dijk, J.C.

    2010-01-01

    In drinking water production, river bank filtration has the advantages of dampening peak concentrations of many dissolved components, substantially removing many micropollutants and removing, virtually completely, the pathogens and suspended solids. The production aquifer is not only fed by the

  8. Water quality and treatment of river bank filtrate

    NARCIS (Netherlands)

    De Vet, W.W.J.M.; Van Genuchten, C.C.A.; Van Loosdrecht, M.C.M.; Van Dijk, J.C.

    2009-01-01

    In drinking water production, river bank filtration has the advantages of dampening peak concentrations of many dissolved components, substantially removing many micropollutants and removing, virtually completely, the pathogens and suspended solids. The production aquifer is not only fed by the

  9. Scaling and particulate fouling in membrane filtration systems

    NARCIS (Netherlands)

    Boerlage, S.F.E.

    2001-01-01

    Membrane filtration technologies have emerged as cost competitive and viable techniques in drinking and industrial water production. Despite advancements in membrane manufacturing and technology, membrane scaling and fouling remain major problems and may limit future growth in the industry. Scaling

  10. Initial testing of electrospun nanofibre filters in water filtration ...

    African Journals Online (AJOL)

    2009-11-17

    Nov 17, 2009 ... for water filtration applications, but that further improvements are necessary before these membranes can be ... power supply, and a grounded collector. .... nanofibres so that the pore size increases and bacteria leak through ...

  11. Thermo-resistant filtration fabrics for hot gas extraction

    International Nuclear Information System (INIS)

    Wierzbowska, T.

    1992-01-01

    Types and technical and utilizing data of heat resistant filtrating fabrics initiated to production by 'Moratex' and provided for dust extraction of technical gas from various industrial processes have been discussed. (author). 8 refs, 2 tabs

  12. Development of a low-cost biogas filtration system to achieve higher-power efficient AC generator

    Science.gov (United States)

    Mojica, Edison E.; Ardaniel, Ar-Ar S.; Leguid, Jeanlou G.; Loyola, Andrea T.

    2018-02-01

    The paper focuses on the development of a low-cost biogas filtration system for alternating current generator to achieve higher efficiency in terms of power production. A raw biogas energy comprises of 57% combustible element and 43% non-combustible elements containing carbon dioxide (36%), water vapor (5%), hydrogen sulfide (0.5%), nitrogen (1%), oxygen (0 - 2%), and ammonia (0 - 1%). The filtration system composes of six stages: stage 1 is the water scrubber filter intended to remove the carbon dioxide and traces of hydrogen sulfide; stage 2 is the silica gel filter intended to reduce the water vapor; stage 3 is the iron sponge filter intended to remove the remaining hydrogen sulfide; stage 4 is the sodium hydroxide solution filter intended to remove the elemental sulfur formed during the interaction of the hydrogen sulfide and the iron sponge and for further removal of carbon dioxide; stage 5 is the silica gel filter intended to further eliminate the water vapor gained in stage 4; and, stage 6 is the activated carbon filter intended to remove the carbon dioxide. The filtration system was able to lower the non-combustible elements by 72% and thus, increasing the combustible element by 54.38%. The unfiltered biogas is capable of generating 16.3 kW while the filtered biogas is capable of generating 18.6 kW. The increased in methane concentration resulted to 14.11% increase in the power output. The outcome resulted to better engine performance in the generation of electricity.

  13. Water Clarity Simulant for K East Basin Filtration Testing

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Andrew J.

    2006-01-20

    This document provides a simulant formulation intended to mimic the behavior of the suspended solids in the K East (KE) Basin fuel storage pool. The simulant will be used to evaluate alternative filtration apparatus to improve Basin water clarity and to possibly replace the existing sandfilter. The simulant was formulated based on the simulant objectives, the key identified parameters important to filtration, the composition and character of the KE Basin suspended sludge particles, and consideration of properties of surrogate materials.

  14. Development of filtration equipment to reuse PFC decontamination wastewater

    International Nuclear Information System (INIS)

    Kim, Gye Nam; Lee, Sung Yeol; Won, Hui Jun; Jung Chong Hun; Oh, Won Zin; Park, Jin Ho

    2005-01-01

    When PFC(Perfluorocarbonate) decontamination technology is applied to removal of radioactive contaminated particulate adhered at surface during the operation of nuclear research facilities, it is necessary to develop a filtration equipment to reuse of PFC solution due to high price, also to minimize the volume of second wastewater. Contaminated characteristics of hot particulate was investigated and a filtration process was presented to remove suspended radioactive particulate from PFC decontamination wastewater generated on PFC decontamination

  15. Development of electromagnetic filtration in the feed water circuits

    International Nuclear Information System (INIS)

    Dolle, L.

    1980-01-01

    Electromagnetic filtration in the feed water circuit of the steam generators in nuclear power plants is efficient towards insoluble corrosion products. The principle of electromagnetic filtration is shortly recalled and the results of corresponding development work are summarized. The magnitude of water volumes to be treated on the two priviledged parts of the circuit are estimated. These parts are on the feed water tank level and on the blow-down of the steam generator. The practical applications are discussed [fr

  16. Apparatus for Crossflow Filtration Testing of High Level Waste Samples

    International Nuclear Information System (INIS)

    Nash, C.

    1998-05-01

    Remotely-operated experimental apparatuses for verifying crossflow filtration of high level nuclear waste have been constructed at the Savannah River Site (SRS). These units have been used to demonstrate filtration processes at the Savannah River Site, Oak Ridge National Laboratory, the Idaho National Engineering and Environmental Laboratory, and Pacific Northwest National Laboratory. The current work covers the design considerations for experimentation as well as providing results from testing at SRS

  17. [Why? How? What for? We must measure the glomerular filtration].

    Science.gov (United States)

    Treviño-Becerra, Alejandro

    2010-01-01

    The measurement of the glomerular filtration shows the degree of the functional qualities and the proficiency of the renal system. Despite new technologies, at present the best accepted technique for measuring the glomerular filtration in most countries is the clearance of creatinine in 24 hour urine. The clearance of creatinine has the advantage that it is confident, easy to reproduce, without technical limitations and low cost.

  18. Fluoride Rinses, Gels and Foams

    DEFF Research Database (Denmark)

    Twetman, Svante; Keller, Mette K

    2016-01-01

    AIM: The aim of this conference paper was to systematically review the quality of evidence and summarize the findings of clinical trials published after 2002 using fluoride mouth rinses, fluoride gels or foams for the prevention of dental caries. METHODS: Relevant papers were selected after...... (6 on fluoride mouth rinse, 10 on fluoride gel and 3 on fluoride foam); 6 had a low risk of bias while 2 had a moderate risk. All fluoride measures appeared to be beneficial in preventing crown caries and reversing root caries, but the quality of evidence was graded as low for fluoride mouth rinse......, moderate for fluoride gel and very low for acidulated fluoride foam. No conclusions could be drawn on the cost-effectiveness. CONCLUSIONS: This review, covering the recent decade, has further substantiated the evidence for a caries-preventive effect of fluoride mouth rinse, fluoride gel and foam...

  19. Hanford underground storage tank waste filtration process evaluation

    International Nuclear Information System (INIS)

    Walker, B.W.; McCabe, D.J.

    1997-01-01

    The purpose of this filter study was to evaluate cross-flow filtration as effective solid-liquid separation technology for treating Hanford wastes, outline operating conditions for equipment, examine the expected filter flow rates, and determine proper cleaning. Two Hanford waste processing applications have been identified as candidates for the use of cross-flow filtration. The first of the Hanford applications involves filtration of the decanted supernate from sludge leaching and washing operations. This process involves the concentration and removal of dilute (0.05 wt percent) fines from the bulk of the supernate. The second application involves filtration to wash and concentrate the sludge during out-of-tank processing. This process employs a relatively concentrated (8 wt percent) solids feed stream. Filter studies were conducted with simulants to evaluate whether 0.5 micron cross-flow sintered metal Mott filters and 0.1 micron cross-flow Graver filters can perform solid-liquid separation of the solid/liquid waste streams effectively. In cross-flow filtration the fluid to be filtered flows in parallel to the membrane surface and generates shearing forces and/or turbulence across the filter medium. This shearing influences formation of filter cake stabilizing the filtrate flow rate

  20. Wind Turbine Gearbox Oil Filtration and Condition Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, Shuangwen

    2015-10-25

    This is an invited presentation for a pre-conference workshop, titled advances and opportunities in lubrication: wind turbine, at the 2015 Society of Tribologists and Lubrication Engineers (STLE) Tribology Frontiers Conference held in Denver, CO. It gives a brief overview of wind turbine gearbox oil filtration and condition monitoring by highlighting typical industry practices and challenges. The presentation starts with an introduction by covering recent growth of global wind industry, reliability challenges, benefits of oil filtration and condition monitoring, and financial incentives to conduct wind operation and maintenance research, which includes gearbox oil filtration and condition monitoring work presented herein. Then, the presentation moves on to oil filtration by stressing the benefits of filtration, discussing typical main- and offline-loop practices, highlighting important factors considered when specifying a filtration system, and illustrating real-world application challenges through a cold-start example. In the next section on oil condition monitoring, a discussion on oil sample analysis, oil debris monitoring, oil cleanliness measurements and filter analysis is given based on testing results mostly obtained by and at NREL, and by pointing out a few challenges with oil sample analysis. The presentation concludes with a brief touch on future research and development (R and D) opportunities. It is hoping that the information presented can inform the STLE community to start or redirect their R and D work to help the wind industry advance.

  1. Silica Sol-Gel Entrapment of the Enzyme Chloro peroxidase

    International Nuclear Information System (INIS)

    Le, T.; Chan, S.; Ebaid, B.; Sommerhalter, M.

    2015-01-01

    The enzyme chloro peroxidase (CPO) was immobilized in silica sol-gel beads prepared from tetramethoxysilane. The average pore diameter of the silica host structure (∼3 nm) was smaller than the globular CPO diameter (∼6 nm) and the enzyme remained entrapped after sol-gel maturation. The catalytic performance of the entrapped enzyme was assessed via the pyrogallol peroxidation reaction. Sol-gel beads loaded with 4 μg CPO per mL sol solution reached 9-12% relative activity compared to free CPO in solution. Enzyme kinetic analysis revealed a decrease in K_cat but no changes in K_M or K_I . Product release or enzyme damage might thus limit catalytic performance. Yet circular dichroism and visible absorption spectra of transparent CPO sol-gel sheets did not indicate enzyme damage. Activity decline due to methanol exposure was shown to be reversible in solution. To improve catalytic performance the sol-gel protocol was modified. The incorporation of 5, 20, or 40% methyltrimethoxysilane resulted in more brittle sol-gel beads but the catalytic performance increased to 14% relative to free CPO in solution. The use of more acidic casting buffers (ph 4.5 or 5.5 instead of 6.5) resulted in a more porous silica host reaching up to 18% relative activity

  2. Formation and rupture of Ca(2+) induced pectin biopolymer gels.

    Science.gov (United States)

    Basak, Rajib; Bandyopadhyay, Ranjini

    2014-10-07

    When calcium salts are added to an aqueous solution of polysaccharide pectin, ionic cross-links form between pectin chains, giving rise to a gel network in dilute solution. In this work, dynamic light scattering (DLS) is employed to study the microscopic dynamics of the fractal aggregates (flocs) that constitute the gels, while rheological measurements are carried out to study the process of gel rupture. As the calcium salt concentration is increased, DLS experiments reveal that the polydispersity of the flocs increase simultaneously with the characteristic relaxation times of the gel network. Above a critical salt concentration, the flocs become interlinked to form a reaction-limited fractal gel network. Rheological studies demonstrate that the limits of the linear rheological response and the critical stresses required to rupture these networks both decrease with the increase in salt concentration. These features indicate that the ion-mediated pectin gels studied here lie in a 'strong link' regime that is characterised by inter-floc links that are stronger than intra-floc links. A scaling analysis of the experimental data presented here demonstrates that the elasticities of the individual fractal flocs exhibit power-law dependences on the added salt concentration. We conclude that when both pectin and salt concentrations are increased, the number of fractal flocs of pectin increases simultaneously with the density of crosslinks, giving rise to very large values of the bulk elastic modulus.

  3. High lane density slab-gel electrophoresis using micromachined instrumentation.

    Science.gov (United States)

    Papautsky, I; Mohanty, S; Weiss, R; Frazier, A B

    2001-10-01

    In this paper, micromachined pipette arrays (MPAs) and microcombs were studied as a means of enabling high lane density gel electrophoresis. The MPA provide a miniaturized format to interface sub-microliter volumes of samples between macroscale sample preparation formats and microscale biochemical analysis systems. The microcombs provide a means of creating sample loading wells in the gel material on the same center-to-center spacing as the MPAs. Together, the two micromachined instruments provide an alternative to current combs and pipetting technologies used for creating sample loading wells and sample delivery in gel electrophoresis systems. Using three designs for the microcomb-MPA pair, center-to-center spacings of 1.0 mm, 500 microm, and 250 microm are studied. The results demonstrate an approximate 10-fold increase in lane density and a 10-fold reduction in sample size from 5 microL to 500 pL. As a result, the number of theoretical plates has increased 2.5-fold, while system resolution has increased 1.5-fold over the conventional agarose gel systems. An examination of changes in resolution across the width of individual separation lanes in both systems revealed dependence in the case of the conventional gels and no dependence for the gels loaded with the micromachined instrumentation.

  4. Gel electrophoresis of inorganic cations

    International Nuclear Information System (INIS)

    Schoenhofer, F.; Grass, F.

    1978-01-01

    In order to be able to separate the largest possible amounts of substance, polyacryl amide gel (PAA) and silica gel are used as carrier for the electrophoresis. Milligramme quantities can easily be separated on PAA gel plates. Electrophoretic ion focussing considerably improves it. Separations of Sr/Y and lanthanoids were carried out. The behaviour of the readily soluble complexing agent acids on silica gel thin layers was minutely investigated and an interpretation of the focussing effect was derived. The conditions for separating radionuclides were optimized. A further improved separation can be achieved by a time sequence combination of normal electrophoresis and ion focussing. Selective isolation methods are advantageous to determine radionuclide traces in environmental samples. The selective adsorption on preformed deposits was transferred to electrophoresis. After pre-investigations on silica gel layers, strontium and barium could also be retained on PAA gel and radium on strontium sulphate in PAA, whereas the disturbing calcium can easily pass through. Cesium can also be retained by prussian blue in the electrophoresis. (orig.) [de

  5. Prediction of the filtrate particle size distribution from the pore size distribution in membrane filtration: Numerical correlations from computer simulations

    Science.gov (United States)

    Marrufo-Hernández, Norma Alejandra; Hernández-Guerrero, Maribel; Nápoles-Duarte, José Manuel; Palomares-Báez, Juan Pedro; Chávez-Rojo, Marco Antonio

    2018-03-01

    We present a computational model that describes the diffusion of a hard spheres colloidal fluid through a membrane. The membrane matrix is modeled as a series of flat parallel planes with circular pores of different sizes and random spatial distribution. This model was employed to determine how the size distribution of the colloidal filtrate depends on the size distributions of both, the particles in the feed and the pores of the membrane, as well as to describe the filtration kinetics. A Brownian dynamics simulation study considering normal distributions was developed in order to determine empirical correlations between the parameters that characterize these distributions. The model can also be extended to other distributions such as log-normal. This study could, therefore, facilitate the selection of membranes for industrial or scientific filtration processes once the size distribution of the feed is known and the expected characteristics in the filtrate have been defined.

  6. Polyaluminium chloride as an alternative to alum for the direct filtration of drinking water.

    Science.gov (United States)

    Zarchi, Idit; Friedler, Eran; Rebhun, Menahem

    2013-01-01

    The efficiency of various polyaluminium chloride coagulants (PACls) was compared to the efficiency of aluminium sulfate (alum) in the coagulation-flocculation process preceding direct filtration in drinking water treatment. The comparative study consisted of two separate yet complementary series of experiments: the first series included short (5-7 h) and long (24 h) filter runs conducted at a pilot filtration plant equipped with large filter columns that simulated full-scale filters. Partially treated surface water from the Sea of Galilee, characterized by very low turbidity (-1 NTU), was used. In the second series of experiments, speciation of aluminium in situ was investigated using the ferron assay method. Results from the pilot-scale study indicate that most PACls were as or more efficient a coagulant as alum for direct filtration of surface water without requiring acid addition for pH adjustment and subsequent base addition for re-stabilizing the water. Consequently, cost analysis of the chemicals needed for the process showed that treatment with PACl would be significantly less costly than treatment with alum. The aluminium speciation experiments revealed that the performance of the coagulant is more influenced by the species present during the coagulation process than those present in the original reagents.

  7. Effect of Canal Bank Filtration on Quality of Water Long Hyderabad City

    Directory of Open Access Journals (Sweden)

    IMDAD ALI KANDHAR

    2016-07-01

    Full Text Available The focus of the present study was to examine the effect of canal bank filtration on the quality of water and the geological settings along the banks of canals at the shallow depth aquifers. The four Model wells were drilled at different locations of the Line channel, Pinyari and phulali canals in the study area. The samples of soil were collected throughout drilling of the model wells for the analysis of grain size distribution .In addition to this, canal water and model well water samples were collected and analyzed for the water quality characteristics during winter and summer seasons. The analysis of soil and water samples reveals that the ground water is influenced by the grain size distribution, hydraulic conductivity and the location of the model Wells. The model well that has higher percentage of 0.075 mm of grain size distribution(hydraulic conductivity between 10-25 ft/day was more suitable for the filtration of the canal water through its banks, followed by 0.15 mm of grain size distribution (hydraulic conductivity > 25ft/ day. Moreover, the present study also shows that the canal water filtration is suitable in terms of total alkalinity, nitrate-nitrogen, total iron and pH to get the potable water at the location near upstream of the canal, especially in the summer season.

  8. Effects of a K+ channel blocker on glomerular filtration rate and electrolyte excretion in conscious rats.

    Science.gov (United States)

    Ludens, J H; Clark, M A; Lawson, J A

    1995-06-01

    Effects of a K+ channel blocker on glomerular filtration rate and electrolyte excretion in conscious rats were observed. Effects of K+ channel modulation on glomerular filtration rate and electrolyte excretion were studied using the adenosine-triphosphate- (ATP)-sensitive K+ channel blocker 4-morpholinecarboximidine-N-1-adamantyl-N'-cyclohexylhydr ochloride (U-37883A) in conscious rats previously equipped with catheters for clearance studies. In saline-loaded rats, i.v. doses of U-37883A of 1.7, 5.0 and 15 mg/kg increased absolute and fractional Na+ excretion dose-dependently without changing K+ excretion. The glomerular filtration rate remained constant during diuresis. In water-loaded (hypotonic dextrose) rats, free-water clearance studies revealed that the ATP-sensitive K+ channel blocker significantly decreased an index of solute reabsorption (free-water clearance adjusted for chloride clearance) in the diluting segment during peak natriuretic activity. In addition, U-37883A significantly decreased the osmolality of renal papillary interstitial fluid, indicative of an effect in the medullary portion of the diluting segment. Together, these findings suggest that ATP-sensitive K+ channels, possibly those located at the apical boarder, play a pivotal role in Na+ reabsorption in the thick ascending limb of the loop of Henle.

  9. Effect of temperature on the morphology and electro-optical properties of liquid crystal physical gel

    International Nuclear Information System (INIS)

    Leaw, W.L.; Mamat, C.R.; Triwahyono, S.; Jalil, A.A.; Bidin, N.

    2016-01-01

    Liquid crystal physical gels were (thermally) prepared with cholesteryl stearate as a gelator in nematic liquid crystal, 4-cyano-4′-pentylbiphenyl. The electro-optical performance of liquid crystal physical gels is almost entirely dependent on the gels' inherent morphology. This study involved an empirical investigation of the relationships among all of the gelation temperature, morphology, and electro-optical properties. Besides continuous cooling at room temperature, isothermal cooling was also performed at both 18 and 0 °C, corresponding to near-solid and solid phases of 4-cyano-4′-pentylbiphenyl respectively. Nevertheless, the liquid crystal physical gel was also isothermally rapidly cooled using liquid nitrogen. Polarizing optical microscopy showed that the gel structure became thinner when isothermal cooling was carried out. These thinner gel aggregates then interconnected to form larger liquid crystal domains. Moreover, it was also revealed that the gel networks were randomized. Electron spin resonance results showed that the liquid crystal director orientation was severely randomized in the presence of gel networks. Conversely, isothermal cooling using liquid nitrogen generated a higher liquid crystal director orientation order. The 6.0 wt% cholesteryl stearate/4-cyano-4′-pentylbiphenyl physical gel that was isothermally cooled using liquid nitrogen showed the lowest response time in a twisted nematic mode optical cell. - Graphical abstract: Liquid crystal physical gel was prepared using nematic liquid crystal, 4-cyano-4′-pentylbiphenyl and cholesteryl stearate as gelator. Isothermal cooling at lower temperature produced thinner gel network and larger liquid crystal domain. - Highlights: • 5CB nematic liquid crystal was successfully gelled by cholesteryl stearate gelator. • The morphology of gel network was controlled by different cooling conditions. • Thinner gel network was formed by the rapid cooling using liquid nitrogen. • Enhanced

  10. Effect of temperature on the morphology and electro-optical properties of liquid crystal physical gel

    Energy Technology Data Exchange (ETDEWEB)

    Leaw, W.L. [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia); Mamat, C.R., E-mail: che@kimia.fs.utm.my [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia); Triwahyono, S. [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia); Jalil, A.A. [Department of Chemical Engineering, Faculty of Chemical and Energy Engineering, Universiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia); Centre of Hydrogen Energy, Institute of Future Energy, Univerisiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia); Bidin, N. [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia)

    2016-12-01

    Liquid crystal physical gels were (thermally) prepared with cholesteryl stearate as a gelator in nematic liquid crystal, 4-cyano-4′-pentylbiphenyl. The electro-optical performance of liquid crystal physical gels is almost entirely dependent on the gels' inherent morphology. This study involved an empirical investigation of the relationships among all of the gelation temperature, morphology, and electro-optical properties. Besides continuous cooling at room temperature, isothermal cooling was also performed at both 18 and 0 °C, corresponding to near-solid and solid phases of 4-cyano-4′-pentylbiphenyl respectively. Nevertheless, the liquid crystal physical gel was also isothermally rapidly cooled using liquid nitrogen. Polarizing optical microscopy showed that the gel structure became thinner when isothermal cooling was carried out. These thinner gel aggregates then interconnected to form larger liquid crystal domains. Moreover, it was also revealed that the gel networks were randomized. Electron spin resonance results showed that the liquid crystal director orientation was severely randomized in the presence of gel networks. Conversely, isothermal cooling using liquid nitrogen generated a higher liquid crystal director orientation order. The 6.0 wt% cholesteryl stearate/4-cyano-4′-pentylbiphenyl physical gel that was isothermally cooled using liquid nitrogen showed the lowest response time in a twisted nematic mode optical cell. - Graphical abstract: Liquid crystal physical gel was prepared using nematic liquid crystal, 4-cyano-4′-pentylbiphenyl and cholesteryl stearate as gelator. Isothermal cooling at lower temperature produced thinner gel network and larger liquid crystal domain. - Highlights: • 5CB nematic liquid crystal was successfully gelled by cholesteryl stearate gelator. • The morphology of gel network was controlled by different cooling conditions. • Thinner gel network was formed by the rapid cooling using liquid nitrogen.

  11. Circadian Rhythm of Glomerular Filtration and Solute Handling Related to Nocturnal Enuresis.

    Science.gov (United States)

    Dossche, L; Raes, A; Hoebeke, P; De Bruyne, P; Vande Walle, J

    2016-01-01

    Although nocturnal polyuria in patients with monosymptomatic enuresis can largely be explained by the decreased nocturnal vasopressin secretion hypothesis, other circadian rhythms in the kidney also seem to have a role. We recently documented an absent day/night rhythm in a subgroup of desmopressin refractory cases. We explore the importance of abnormal circadian rhythm of glomerular filtration and tubular (sodium, potassium) parameters in patients with monosymptomatic enuresis. In this retrospective study of a tertiary enuresis population we collected data subsequent to a standardized screening (International Children's Continence Society questionnaire), 14-day diary for nocturnal enuresis and diuresis, and 24-hour concentration profile. The study population consisted of 139 children with nocturnal enuresis who were 5 years or older. Children with nonmonosymptomatic nocturnal enuresis were used as controls. There was a maintained circadian rhythm of glomerular filtration, sodium, osmotic excretion and diuresis rate in children with monosymptomatic and nonmonosymptomatic nocturnal enuresis, and there was no difference between the 2 groups. Secondary analysis revealed that in patients with nocturnal polyuria (with monosymptomatic or nonmonosymptomatic nocturnal enuresis) circadian rhythm of glomerular filtration, sodium and osmotic excretion, and diuresis rate was diminished in contrast to those without nocturnal polyuria (p Circadian rhythm of the kidney does not differ between patients with nonmonosymptomatic and monosymptomatic enuresis. However, the subgroup with enuresis and nocturnal polyuria has a diminished circadian rhythm of nocturnal diuresis, sodium excretion and glomerular filtration in contrast to children without nocturnal polyuria. This observation cannot be explained by the vasopressin theory alone. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  12. Research of process of filtration of salt water by bulk filters with the use of vibration

    Directory of Open Access Journals (Sweden)

    A. I. Krikun

    2018-01-01

    Full Text Available For the purification of process water from impurities at fish processing plants, a large number of filtering devices are currently used, differing in their design parameters (mesh, woven, disco, etc.. However, in practice, these filtering devices are mainly used as the first stage of water treatment, since they can not provide sufficient quality of the filtrate. The most effective, as numerous studies of scientists of our country and the world show, are bulk granular filters. Their main advantages over other devices of similar designation are: they have a simple and reliable design; resistant to aggressive operating conditions; they are capable of effectively purifying seawater from mechanical impurities at relatively low pressure; most economical; have a filtering load capable of a long time to work without regeneration (the approximate service life of a grain-loading is 3 to 5 years etc. In this article, the influence of vibration effects on the filtration of sea water in a designed and fabricated filter unit with bulk granular materials of natural and artificial origin, the design of which is protected by two patents for the utility model. The results of the study are presented, revealing the degree of influence of the intensity of vibration of the perforated partitioning wall on the state of bulk granular materials located on it (segregation by size, stratified vibro-packing, compacting or loosening of a layer of granular material. The dependences of the capacity of the filtration unit on the amplitude, frequency and the vibration intensity factor have been experimentally established, which made it possible to establish rational vibration parameters of the perforated septum, under which the filtering layer becomes denser, the porosity of the loading decreases, and the precipitate does not break into the filtrate.

  13. Mitigation of radon and thoron decay products by filtration

    International Nuclear Information System (INIS)

    Wang Jin; Meisenberg, Oliver; Chen Yongheng; Karg, Erwin; Tschiersch, Jochen

    2011-01-01

    Inhalation of indoor radon ( 222 Rn) and thoron ( 220 Rn) decay products is the most important source of exposure to ionizing radiation for the human respiratory tract. Decreasing ventilation rates due to energy saving reasons in new buildings suggest additional active mitigation techniques to reduce the exposure in homes with high radon and thoron concentrations but poor ventilation. Filtration techniques with HEPA filters and simple surgical mask material have been tested for their potential to reduce the indoor exposure in terms of the total effective dose for mixed radon and thoron indoor atmospheres. The tests were performed inside an experimental room providing stable conditions. Filtration (at filtration rates of 0.2 h -1 and larger) removes attached radon and thoron decay products effectively but indoor aerosol as well. Therefore the concentration of unattached decay products (which have a higher dose coefficient) may increase. The decrease of the attached decay product concentrations could be theoretically described by a slowly decreasing exponential process. For attached radon decay products, it exhibited a faster but weaker removal process compared to attached thoron decay products (- 70% for attached radon decay products and - 80% for attached thoron decay products at a filtration rate of 0.5 h -1 with an HEPA filter). The concentration of unattached thoron decay products increased distinctly during the filtration process (+ 300%) while that of unattached radon decay products rose only slightly though at a much higher level (+ 17%). In the theoretical description these observed differences could be attributed to the different half-lives of the nuclides. Considering both effects, reduced attached and increased unattached decay product concentrations, filtration could significantly decrease the total effective dose from thoron whereas the overall effect on radon dose is small. A permanent filtration is recommended because of the slow decrease of the

  14. NMR mechanisms in gel dosimetry

    International Nuclear Information System (INIS)

    Schreiner, L J

    2009-01-01

    Nuclear magnetic resonance was critical to the development of gel dosimetry, as it established the potential for three dimensional dosimetry with chemical dosimeter systems through magnetic resonance imaging [1]. In the last two decades MRI has served as the gold standard for imaging, while NMR relaxometry has played an important role in the development and understanding of the behaviour of new gel dosimetry systems. Therefore, an appreciation of the relaxation mechanisms determining the NMR behaviour of irradiated gel dosimeters is important for a full comprehension of a considerable component of the literature on gel dosimetry. A number of excellent papers have presented this important theory, this brief review will highlight some of the salient points made previously [1-5]. The spin relaxation of gel dosimeters (which determines the dose dependence in most conventional MR imaging) is determined principally by the protons on water molecules in the system. These water protons exist in different environments, or groups (see Figure 1): on bulk water, on water hydrating the chemical species that are being modified under irradiation, and on water hydrating the gel matrix used to spatially stabilize the dosimeter (e.g., gelatin, agarose, etc). The spin relaxation depends on the inherent relaxation rate of each spin group, that is, on the relaxation rate which would be observed for the specific group if it were isolated. Also, the different water environments are not isolated from each other, and the observed relaxation rate also depends on the rate of exchange of magnetization between the groups, and on the fraction of protons in each group. In fact, the water exchanges quickly between the environments, so that relaxation is in what is usually termed the fast exchange regime. In the limit of fast exchange, the relaxation of the water protons is well characterized by a single exponential and hence by a single apparent relaxation rate. In irradiated gel dosimeters this

  15. New insights into uranium (VI) sol-gel processing

    International Nuclear Information System (INIS)

    King, C.M.; Thompson, M.C.; Buchanan, B.R.; King, R.B.; Garber, A.R.

    1990-01-01

    Nuclear Magnetic Resonance (NMR) investigations on the Oak Ridge National Laboratory process for sol-gel synthesis of microspherical nuclear fuel (UO 2 ), has been extremely useful in sorting out the chemical mechanism in the sol-gel steps. 13 C, 15 N, and 1 H NMR studies on the HMTA gelation agent (Hexamethylene tetramine, C 6 H 12 N 4 ) has revealed near quantitative stability of this adamantane-like compound in the sol-gel process, contrary to its historical role as an ammonia source for gelation from the worldwide technical literature. 17 O NMR of uranyl (UO 2 ++ ) hydrolysis fragments produced in colloidal sols has revealed the selective formation of a uranyl trimer, [(UO 2 ) 3 (μ 3 -O)(μ 2 -OH) 3 ] + , induced by basic hydrolysis with the HMTA gelation agent. Spectroscopic results will be presented to illustrate that trimer condensation occurs during sol-gel processing leading to layered polyanionic hydrous uranium oxides in which HMTAH + is occluded as an ''intercalation'' cation. Subsequent sol-gel processing of microspheres by ammonia washing results in in-situ exchange and formation of a layered hydrous ammonium uranate with a proposed structural formula of (NH 4 ) 2 [(UO 2 ) 8 O 4 (OH) 10 ] · 8H 2 O. This compound is the precursor to sintered UO 2 ceramic fuel. 23 refs., 10 figs

  16. Fast and facile preparation of CTAB based gels and their applications in Au and Ag nanoparticles synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Upadhyay, Ravi Kant, E-mail: rkupadhyay85@gmail.com [Department of Chemistry, School of Natural Sciences, Shiv Nadar University, Gautam Budh Nagar, 201314 Uttar Pradesh (India); Soin, Navneet, E-mail: n.soin@bolton.ac.uk [Knowledge Centre for Materials Chemistry (KCMC), Institute for Materials Research and Innovation (IMRI), University of Bolton, Deane Road, Bolton BL3 5AB (United Kingdom); Saha, Susmita, E-mail: ssaha@bose.res.in [Department of Condensed Matter Physics and Material Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700 098 (India); Barman, Anjan, E-mail: abarman@bose.res.in [Department of Condensed Matter Physics and Material Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700 098 (India); Sinha Roy, Susanta, E-mail: susanta.roy@snu.edu.in [Department of Physics, School of Natural Sciences, Shiv Nadar University, Gautam Budh Nagar, 201314 Uttar Pradesh (India)

    2015-04-15

    We have demonstrated that the gel-like mesophase of Cetyltrimethylammonium bromide (CTAB) can be synthesized by judicial adjustment of water to surfactant molar ratio (W{sub 0}), without using any additional salts, gelating agents or co-surfactants. Gel formation was found to be highly dependent on the water to surfactant molar ratio (W{sub 0}), with the lowest value of W{sub 0} (41.5) resulting in rapid gel formation. Environmental scanning electron microscope (ESEM) analysis revealed that the gel was comprised of interconnected cylindrical structures. The presence of hydrogen bonding in the gel-like mesophase was confirmed by Fourier Transform Infrared spectroscopy (FTIR) analysis. Rheology measurements revealed that all the gel samples were highly viscoelastic in nature. Furthermore, Au and Ag containing CTAB gels were explored as precursors for the preparation of spherical Gold (Au) and Silver (Ag) nanoparticles using Sodium borohydride (NaBH{sub 4}) as reducing agent. The effects of NaBH{sub 4} concentration on the particle size and morphology of the Au and Ag nanoparticles have also been studied. - Highlights: • A facile synthesis of CTAB based gel-like mesophase is reported. • CTAB gels were obtained by adjusting water to surfactant molar ratio (W{sub 0}). • FTIR analysis revealed that hydrogen bonding plays a key role in gel formation. • Au, Ag nanoparticles were synthesized by using CTAB gel and NaBH{sub 4}.

  17. Four years experience with filtration systems in commercial nurseries for eliminating Phytophthora species from recirculation water

    Science.gov (United States)

    T. Ufer; M. Posner; H.-P. Wessels; S. Wagner; K. Kaminski; T. Brand; Werres S.

    2008-01-01

    In a four year project, three different filtration systems were tested under commercial nursery conditions to eliminate Phytophthora spp. from irrigation water. Five nurseries were involved in the project. Slow sand filtration systems were tested in three nurseries. In the fourth nursery, a filtration system with lava grains (Shieer® Bio filtration)...

  18. Thermal behaviour of strontium tartrate single crystals grown in gel

    Indian Academy of Sciences (India)

    Thermal behaviour of strontium tartrate crystals grown with the aid of sodium metasilicate gel is investigated using thermogravimetry (TG) and differential thermal analysis (DTA). Effect of magnetic field and dopant (Pb)2+ on the crystal stability is also studied using thermal analysis. This study reveals that water molecules are ...

  19. Self Cleaning HEPA Filtration without Interrupting Process Flow

    International Nuclear Information System (INIS)

    Wylde, M.

    2009-01-01

    The strategy of protecting the traditional glass fibre HEPA filtration train from it's blinding contamination and the recovery of dust by the means of self cleaning, pre-filtration is a proven means in the reduction of ultimate disposal volumes and has been used within the Fuel Production Industry. However, there is an increasing demand in nuclear applications requiring elevated operating temperatures, fire resistance, moisture resistance and chemical composition that the existing glass fibre HEPA filtration cannot accommodate, which can be remedied by the use of a metallic HEPA filter media. Previous research (Bergman et al 1997, Moore et al 1992) suggests that the then costs to the DOE, based on a five year life cycle, was $29.5 million for the installation, testing, removal and disposal of glass fibre HEPA filtration trains. Within these costs, $300 was the value given to the filter and $4,450 was given to the peripheral activity. Development of a low cost, cleanable, metallic, direct replacement of the traditional filter train will the clear solution. The Bergman et al work has suggested that a 1000 ft 3 /min, cleanable, stainless HEPA could be commercially available for $5,000 each, whereas the industry has determined that the truer cost of such an item in isolation would be closer to $15,000. This results in a conflict within the requirement between 'low cost' and 'stainless HEPA'. By proposing a system that combines metallic HEPA filtration with the ability to self clean without interrupting the process flow, the need for a tradition HEPA filtration train will be eliminated and this dramatically reduces the resources required for cleaning or disposal, thus presenting a route to reducing ultimate costs. The paper will examine the performance characteristics, filtration efficiency, flow verses differential pressure and cleanability of a self cleaning HEPA grade sintered metal filter element, together with data to prove the contention. (authors)

  20. Thixotropic gel for vadose zone remediation

    Science.gov (United States)

    Rhia, Brian D [Augusta, GA

    2011-03-01

    A thixotropic gel suitable for use in subsurface bioremediation is provided along with a process of using the gel. The thixotropic gel provides a non-migrating injectable substrate that can provide below ground barrier properties. In addition, the gel components provide for a favorable environment in which certain contaminants are preferentially sequestered in the gel and subsequently remediated by either indigenous or introduced microorganisms.

  1. Influence of remineralizing gels on bleached enamel microhardness in different time intervals.

    Science.gov (United States)

    Borges, Alessandra Bühler; Yui, Karen Cristina Kazue; D'Avila, Thaís Corrêa; Takahashi, Camila Lurie; Torres, Carlos Rocha Gomes; Borges, Alexandre Luis Souto

    2010-01-01

    This study evaluated the influence of bleaching gel pH, the effect of applying remineralizing gels after bleaching and the effect of artificial saliva on enamel microhardness. Seventy bovine incisors were divided into three groups: Group 1 (n=10) received no bleaching procedure (control); Group 2 was bleached with a 35% hydrogen peroxide neutral gel (n=30) and Group 3 was bleached with a 35% hydrogen peroxide acid gel (n=30). Each experimental group was subdivided into three groups (n=10) according to the post-bleaching treatment: storage in artificial saliva, application of a fluoride gel and application of a combination of calcium and fluoride gel. The specimens were stored in artificial saliva for 7, 15 and 30 days and enamel microhardness was evaluated. The Vickers microhardness data were analyzed by three-way RM ANOVA, which revealed a significant difference only for treatment factor. The Tukey's test showed that the groups bleached followed by no additional treatment exhibited microhardness means significantly lower than the bleached groups treated with remineralizing gels. The Dunnet's test showed a significant difference only for the group bleached with acid gel without remineralizing treatment compared to the control group measured immediately after bleaching. It was concluded that acid bleaching gel significantly reduced enamel microhardness and that use of remineralizing gels after bleaching can significantly enhance the microhardness of bleached enamel.

  2. Surface grafted chitosan gels. Part II. Gel formation and characterization

    DEFF Research Database (Denmark)

    Liu, Chao; Thormann, Esben; Claesson, Per M.

    2014-01-01

    Responsive biomaterial hydrogels attract significant attention due to their biocompatibility and degradability. In order to make chitosan based gels, we first graft one layer of chitosan to silica, and then build a chitosan/poly(acrylic acid) multilayer using the layer-by-layer approach. After...... cross-linking the chitosan present in the polyelectrolyte multilayer, poly(acrylic acid) is partly removed by exposing the multilayer structure to a concentrated carbonate buffer solution at a high pH, leaving a surface-grafted cross-linked gel. Chemical cross-linking enhances the gel stability against...... detachment and decomposition. The chemical reaction between gluteraldehyde, the cross-linking agent, and chitosan was followed in situ using total internal reflection Raman (TIRR) spectroscopy, which provided a molecular insight into the complex reaction mechanism, as well as the means to quantify the cross...

  3. Preparation of gold nanoparticles-agarose gel composite and its application in SERS detection

    Science.gov (United States)

    Ma, Xiaoyuan; Xia, Yu; Ni, Lili; Song, Liangjing; Wang, Zhouping

    2014-03-01

    Agarose gel/gold nanoparticles hybrid was prepared by adding gold nanoparticles to preformed agarose gel. Nanocomposite structures and properties were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and UV-Vis-NIR absorption spectroscopy. Based on the swelling-contraction characteristics of agarose gel and the adjustable localized surface plasmon resonance (LSPR) of the gold nanoparticles, the nanocomposites were used as surface enhanced Raman scattering (SERS) substrate to detect the Raman signal molecules (NBA, MBA, 1NAT). Results revealed that the porous structure of the agarose gel provided a good carrier for the enrichment of the gold nanoparticles. The gold nanoparticles dynamic hot-spot effect arising from the agarose gel contraction loss of water in the air greatly enhanced the Raman signal. Furthermore, the gel could be cleaned with washing solution and recycling could be achieved for Raman detection.

  4. A rapid and efficient two-step gel electrophoresis method for the purification of major rye grass pollen allergens.

    Science.gov (United States)

    Levy, D; Davies, J; O'Hehir, R; Suphioglu, C

    2001-06-01

    Purified proteins are mandatory for molecular, immunological and cellular studies. However, purification of proteins from complex mixtures requires specialised chromatography methods (i.e., gel filtration, ion exchange, etc.) using fast protein liquid chromatography (FPLC) or high-performance liquid chromatography (HPLC) systems. Such systems are expensive and certain proteins require two or more different steps for sufficient purity and generally result in low recovery. The aim of this study was to develop a rapid, inexpensive and efficient gel-electrophoresis-based protein purification method using basic and readily available laboratory equipment. We have used crude rye grass pollen extract to purify the major allergens Lol p 1 and Lol p 5 as the model protein candidates. Total proteins were resolved on large primary gel and Coomassie Brilliant Blue (CBB)-stained Lol p 1/5 allergens were excised and purified on a secondary "mini"-gel. Purified proteins were extracted from unstained separating gels and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblot analyses. Silver-stained SDS-PAGE gels resolved pure proteins (i.e., 875 microg of Lol p 1 recovered from a 8 mg crude starting material) while immunoblot analysis confirmed immunological reactivity of the purified proteins. Such a purification method is rapid, inexpensive, and efficient in generating proteins of sufficient purity for use in monoclonal antibody (mAb) production, protein sequencing and general molecular, immunological, and cellular studies.

  5. CALCULATION OF LONG-TERM FILTRATION IN A POROUS MEDIUM

    Directory of Open Access Journals (Sweden)

    Ludmila I. Kuzmina

    2018-03-01

    Full Text Available he filtration problem in a porous medium is an important part of underground hydromechanics. Filtration of suspensions and colloids determines the processes of strengthening the soil and creating waterproof walls in the ground while building the foundations of buildings and underground structures. It is assumed that the formation of a deposit is dominated by the size-exclusion mechanism of pore blocking: solid particles pass freely through large pores and get stuck at the inlet of pores smaller than the diameter of the particles. A one-dimensional mathematical model for the filtration of a monodisperse suspension includes the equation for the mass balance of suspended and retained particles and the kinetic equation for the growth of the deposit. For the blocking filtration coefficient with a double root, the exact solution is given implicitly. The asymptotics of the filtration problem is constructed for large time. The numerical calculation of the problem is carried out by the finite differences method. It is shown that asymptotic approximations rapidly converge to a solution with the increase of the expansion order.

  6. Spontaneous water filtration of bio-inspired membrane

    Science.gov (United States)

    Kim, Kiwoong; Kim, Hyejeong; Lee, Sang Joon

    2016-11-01

    Water is one of the most important elements for plants, because it is essential for various metabolic activities. Thus, water management systems of vascular plants, such as water collection and water filtration have been optimized through a long history. In this view point, bio-inspired technologies can be developed by mimicking the nature's strategies for the survival of the fittest. However, most of the underlying biophysical features of the optimized water management systems remain unsolved In this study, the biophysical characteristics of water filtration phenomena in the roots of mangrove are experimentally investigated. To understand water-filtration features of the mangrove, the morphological structures of its roots are analyzed. The electrokinetic properties of the root surface are also examined. Based on the quantitatively analyzed information, filtration of sodium ions in the roots are visualized. Motivated by this mechanism, spontaneous desalination mechanism in the root of mangrove is proposed by combining the electrokinetics and hydrodynamic transportation of ions. This study would be helpful for understanding the water-filtration mechanism of the roots of mangrove and developing a new bio-inspired desalination technology. This research was financially supported by the National Research Foundation (NRF) of Korea (Contract Grant Number: 2008-0061991).

  7. Water quality and treatment of river bank filtrate

    Directory of Open Access Journals (Sweden)

    W. W. J. M. de Vet

    2010-06-01

    Full Text Available In drinking water production, river bank filtration has the advantages of dampening peak concentrations of many dissolved components, substantially removing many micropollutants and removing, virtually completely, the pathogens and suspended solids. The production aquifer is not only fed by the river bank infiltrate but also by water percolating through covering layers. In the polder areas, these top layers consist of peat and deposits from river sediments and sea intrusions.

    This paper discusses the origin and fate of macro components in river bank filtrate, based on extensive full-scale measurements in well fields and treatment systems of the Drinking Water Company Oasen in the Netherlands. First, it clarifies and illustrates redox reactions and the mixing of river bank filtrate and PW as the dominant processes determining the raw water quality for drinking water production. Next, full-scale results are elaborated on to evaluate trickling filtration as an efficient and proven one-step process to remove methane, iron, ammonium and manganese. The interaction of methane and manganese removal with nitrification in these systems is further analyzed. Methane is mostly stripped during trickling filtration and its removal hardly interferes with nitrification. Under specific conditions, microbial manganese removal may play a dominant role.

  8. Oviposition Attractancy of Bacterial Culture Filtrates: response of Culex quinquefasciatus

    Directory of Open Access Journals (Sweden)

    S Poonam

    2002-04-01

    Full Text Available Oviposition attractants could be used for monitoring as well as controlling mosquitoes by attracting them to lay eggs at chosen sites. In the present study, culture filtrates of seven bacterial species were tested for their attractancy against gravid females of Culex quinquefasciatus. When their oviposition active indices (OAI were studied, the culture filtrates of Bacillus cereus and Pseudomonas fluorescens exhibited oviposition attractancy (OAI = >0.3 at 100 ppm and the OAI were respectively 0.70 and 0.47. Culture filtrates of B. thuringiensis var. israelensis (wild type, B. t. var. israelensis (mutant and B. sphaericus showed attractancy at 2000 ppm with OAI of respectively 0.71, 0.59 and 0.68. However, the OAI of B. megaterium as well as Azospirillum brasilense was 0.13 (at 2000 ppm, which was less than 0.3 required to be considered them as attractants. When the oviposition attractancy of the bacterial culture filtrates were compared with that of a known oviposition attractant, p-cresol (at 10 ppm, the culture filtrates of B. t. var. israelensis (wild type and B. cereus were found to be more active than p-cresol, respectively with 64.2 and 54.3% oviposition.

  9. Impact of Acidification on Pollutants Fate and Soil Filtration Function

    Directory of Open Access Journals (Sweden)

    Jarmila Makovniková

    2014-12-01

    Full Text Available The objective of this paper was to investigate the effects of simulated acid load on the fate of inorganic pollutants (Cd, Pb, soil sorption potential, soil filtration func-tion. We made use of a short-term acidification pot experiment with grown plant of spring barley cultivated at 4 different soil types (Fluvisol, Cambisol, Stagnosol, Podzol. The potential of soil filtration was evaluated according to the Eq.: [Soil filtration function]=[Potential of soil sorbents]+[Potential of total content of inor-ganic pollutants]. Potential of soil sorbents (PSS is defined by qualitative (pH, or-ganic matter quality - A400/600 and quantitative factors (carbon content-Cox, humus layer thickness-H according to the Eq.:[PSS]=F(pH+F(A465/665+F(Cox*F(H. Acid load significantly influenced soil sorption potential and thus affected increase in Cd and Pb mobility what was reflected in their transfer into the plants. Results of soil filtration function showed significant change of filtration function in Cambisol.

  10. Sol-gel derived sorbents

    Science.gov (United States)

    Sigman, Michael E.; Dindal, Amy B.

    2003-11-11

    Described is a method for producing copolymerized sol-gel derived sorbent particles for the production of copolymerized sol-gel derived sorbent material. The method for producing copolymerized sol-gel derived sorbent particles comprises adding a basic solution to an aqueous metal alkoxide mixture for a pH.ltoreq.8 to hydrolyze the metal alkoxides. Then, allowing the mixture to react at room temperature for a precalculated period of time for the mixture to undergo an increased in viscosity to obtain a desired pore size and surface area. The copolymerized mixture is then added to an immiscible, nonpolar solvent that has been heated to a sufficient temperature wherein the copolymerized mixture forms a solid upon the addition. The solid is recovered from the mixture, and is ready for use in an active sampling trap or activated for use in a passive sampling trap.

  11. Fundamentals of Polymer Gel Dosimeters

    Science.gov (United States)

    McAuley, Kim B.

    2006-12-01

    The recent literature on polymer gel dosimetry contains application papers and basic experimental studies involving polymethacrylic-acid-based and polyacrylamide-based gel dosimeters. The basic studies assess the relative merits of these two most commonly used dosimeters, and explore the effects of tetrakis hydroxymethyl phosphonium chloride (THPC) antioxidant on dosimeter performance. Polymer gel dosimeters that contain THPC or other oxygen scavengers are called normoxic dosimeters, because they can be prepared under normal atmospheric conditions, rather than in a glove box that excludes oxygen. In this review, an effort is made to explain some of the underlying chemical phenomena that affect dosimeter performance using THPC, and that lead to differences in behaviour between dosimeters made using the two types of monomer systems. Progress on the development of new more effective and less toxic dosimeters is also reported.

  12. Role of pluronics on rheological, drying and crack initiation of 'suckable' gels of decontamination

    International Nuclear Information System (INIS)

    Bousquet, C.

    2007-12-01

    The aim of this work was to understand the role of an addition of pluronics on the rheological behaviour, the drying and the fracturing of 'suckable' gels used for nuclear decontamination. The system studied was an aqueous suspension of silica (100 g/L of Aerosil 380) in a strong acidic medium (HNO 3 /H 3 PO 4 1.5 mol/L/1.5 mol/L) in presence of pluronics. Pluronics are amphiphilic tri-blocks copolymers composed of ethylene poly-oxide blocks and of propylene poly-oxide. The first part of this study deals with the characterization of the rheological properties of the gels. From viscosity retaking measurements, flow rheo-grams analysis and the viscoelastic properties of the gels, have been determined an improvement of the rheological properties of the gels significant from the addition of 5 g/L of copolymer. In a second part, the determination of adsorption isotherms coupled to small angles neutrons diffusion measurements has revealed that copolymers are adsorbed flat on silica in bridging the aggregates between them and that the improvement of the rheological behaviour of the gels is due to the increase of the bonds density of the gelled lattice. Moreover, beyond 10 g/L, the adsorption saturation of copolymers at the surface of the silica prevents the bridging of the aggregates which induces the gel destabilization. The last part of this work deals with the characterization of characteristic values of drying and of crack initiation of gels. Then is revealed a relation between the drying kinetics and the formation of cracks in the gel layer. Moreover, the study of the evolution of stresses in the gel layer during time allows to reveal that the addition of pluronics to the formulation of gels allows to improve the gel resistance to the crack initiation and to the delamination. (O.M.)

  13. Effect of flood-induced chemical load on filtrate quality at bank filtration sites

    Science.gov (United States)

    Ray, C.; Soong, T.W.; Lian, Y.Q.; Roadcap, G.S.

    2002-01-01

    Riparian municipal wells, that are located on riverbanks, are specifically designed to capture a portion of the river water through induced infiltration. Runoff from agricultural watersheds is found to carry enormous amounts of pesticides and nitrate. While the risk of contamination for a vast majority of sites with small-capacity vertical wells is low, potential exists for medium to large capacity collector wells to capture a fraction of the surface water contaminants during flood. Prior monitoring and current modeling results indicate that a small-capacity (peak pumpage 0.0315 m3/s) vertical bank filtration well may not be affected by river water nitrate and atrazine even during flood periods. For a medium capacity (0.0875-0.175 m3/s) hypothetical collector well at the same site, potential exists for a portion of the river water nitrate and atrazine to enter the well during flood periods. Various combinations of hydraulic conductivity of the riverbed or bank material were used. For nitrate, it was assumed either no denitrification occurred during the period of simulation or a half-life of 2 years. Equilibrium controlled sorption (organic carbon partition coefficient of 52 ml/g) and a half-life of between 7.5 and 15 weeks were considered for atrazine. Combinations of these parameters were used in various simulations. Peak concentrations of atrazine or nitrate in pumped water could vary from less than 1% to as high as 90% of that in the river. It was found that a combination of river stage, pumping rates, hydraulic properties of the riverbed and bank, and soil/pesticide properties could affect contaminant entry from river water to any of these wells. If the hydraulic conductivity of the bed and bank material were low, atrazine would not reach the pumping well with or without sorption and degradation. However, for moderately low permeable bank and bed materials, some atrazine from river water could enter a hypothetical collector well while pumping at 0.0875 m3/s. It

  14. The Fundamentals of Waste Water Sludge Characterization and Filtration

    Energy Technology Data Exchange (ETDEWEB)

    Scales, Peter J.; Dixon, David R.; Harbour, Peter J.; Stickland, Anthony D.

    2003-07-01

    The move to greater emphasis on the disposal of waste water sludges through routes such as incineration and the added cost of landfill emplacement puts high demands on dewatering technology for these sludges. A dear problem in this area is that waste water sludges are slow and difficult to dewater and traditional methods of laboratory measurement for prediction of filtration performance are inadequate. This is highly problematic for the design and operational optimisation of centrifuges, filters and settling devices in the waste water industry. The behaviour is assessed as being due to non-linear behaviour of these sludges which negates the use of classical approaches. These approaches utilise the linear portion of a t versus V{sup 2} plot (where t is the time to filtration and V is the specific filtrate volume) to extract a simple Darcian permeability. Without this parameter, a predictive capacity for dewatering using current theory is negated. (author)

  15. C-018H LERF filtration test plan. Revision 1

    International Nuclear Information System (INIS)

    Moberg, T.P.; King, C.V.

    1994-01-01

    The following outlines the plan to test the polymeric backwash filtration system at the LERF. These tests will determine if the ETF filter design is adequate. If the tests show that the design is adequate, the task will be complete. If the tests show that the technology is inadequate, it may be necessary to perform further tests to qualify other candidate filtration technologies (e.g., polymeric tubular ultrafiltration, centrifugal ultrafiltration). The criteria to determine the success or failure of the backwash filter will be based on the system's ability to remove the bacteria and inorganic contaminants from the evaporator process condensate. The tests are designed to qualify the design basis of the filtration technology that will be used in the ETF

  16. Landfill Leachate Treatment by Electrocoagulation and Fiber Filtration.

    Science.gov (United States)

    Li, Runwei; Wang, Boya; Owete, Owete; Dertien, Joe; Lin, Chen; Ahmad, Hafiz; Chen, Gang

    2017-11-01

      Landfilling is widely adopted as one of the most economical processes for solid waste disposal. At the same time, landfill leachate is also a great environmental concern owing to its complex composition and high concentrations of contaminants. This research investigated electrocoagulation and fiber filtration for the treatment of landfill leachate. Besides electrical current (i.e., current density) and reaction time, pH played a very important role in arsenic and phosphorus removal by electrocoagulation. The combination of electrocoagulation with fiber filtration achieved a 94% chemical oxygen demand (COD), 87% arsenic, 96% iron, and 86% phosphorus removal. During electrocoagulation, the micro-particles that could not be settled by gravity were removed by the first stage of fiber filtration. Organic contaminants in the leachate were further removed by biodegradation in the second stage of fiber biofiltration.

  17. Efektifitas Riverbank Filtration Trhadap Parameter Fisik (TDS di Sungai Cihideung

    Directory of Open Access Journals (Sweden)

    Roh Santoso Budi Waspodo

    2013-01-01

    Full Text Available Water is a natural resource that is necessary for the livelihood of many people, even by all living things. Data Ministry of Public Works in 2006 mentions the availability of water in Indonesia amounted to 15,500 cubic meters per capita per year, far higher than the global availability averaged only 600 m3. If drawn, the amount of water covers 21% of Indonesia Pacific Ocean. However, the overflow Indonesia does not necessarily solve the problem of water crisis which is also predicted to fall on two major islands in 2015. The general objective of this research is to develop and implement technological innovations RBF (Riverbank Filtration to support the needs of irrigation water Watershed Cisadane, making RBF (Riverbank Filtration as a natural water treatment in Cisadane River area, and water quality data information through RBF (Riverbank Filtration Cisadane Watershed.

  18. C-018H LERF filtration test plan. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Moberg, T.P.; King, C.V.

    1994-08-26

    The following outlines the plan to test the polymeric backwash filtration system at the LERF. These tests will determine if the ETF filter design is adequate. If the tests show that the design is adequate, the task will be complete. If the tests show that the technology is inadequate, it may be necessary to perform further tests to qualify other candidate filtration technologies (e.g., polymeric tubular ultrafiltration, centrifugal ultrafiltration). The criteria to determine the success or failure of the backwash filter will be based on the system`s ability to remove the bacteria and inorganic contaminants from the evaporator process condensate. The tests are designed to qualify the design basis of the filtration technology that will be used in the ETF.

  19. Simulations of Microbial-Enhanced Oil Recovery: Adsorption and Filtration

    DEFF Research Database (Denmark)

    Nielsen, Sidsel Marie; Nesterov, Igor; Shapiro, Alexander

    2014-01-01

    In the context of microbial-enhanced oil recovery (MEOR) with injection of surfactant-producing bacteria into the reservoir, different types of bacteria attachment and growth scenarios are studied using a 1D simulator. The irreversible bacteria attachment due to filtration similar to the deep bed...... applied to filtration model provides formation of two oil banks during recovery. This feature is not reproduced by application of REA model or DBF with growth in attached phase. This makes it possible to select a right model based on the qualitative analysis of the experimental data. A criterion...... is introduced to study the process efficiency: the dimensionless time at which average recovery between pure water injection and maximum surfactant effect is reached. This characteristic recovery period (CRP) was studied as a function of the different MEOR parameters such as bacterial activity, filtration...

  20. Fusion Kalman filtration with k-step delay sharing pattern

    Directory of Open Access Journals (Sweden)

    Duda Zdzisław

    2015-09-01

    Full Text Available A fusion hierarchical state filtration with k−step delay sharing pattern for a multisensor system is considered. A global state estimate depends on local state estimates determined by local nodes using local information. Local available information consists of local measurements and k−step delay global information - global estimate sent from a central node. Local estimates are transmitted to the central node to be fused. The synthesis of local and global filters is presented. It is shown that a fusion filtration with k−step delay sharing pattern is equivalent to the optimal centralized classical Kalman filtration when local measurements are transmitted to the center node and used to determine a global state estimate. It is proved that the k−step delay sharing pattern can reduce covariances of local state errors.

  1. Grey water treatment in urban slums by a filtration system: optimisation of the filtration medium.

    Science.gov (United States)

    Katukiza, A Y; Ronteltap, M; Niwagaba, C B; Kansiime, F; Lens, P N L

    2014-12-15

    Two uPVC columns (outer diameter 160 cm, internal diameter 14.6 cm and length 100 cm) were operated in parallel and in series to simulate grey water treatment by media based filtration at unsaturated conditions and constant hydraulic loading rates (HLR). Grey water from bathroom, laundry and kitchen activities was collected from 10 households in the Bwaise III slum in Kampala (Uganda) in separate containers, mixed in equal proportions followed by settling, prior to transferring the influent to the tanks. Column 1 was packed with lava rock to a depth of 60 cm, while column 2 was packed with lava rock (bottom 30 cm) and silica sand, which was later replaced by granular activated carbon (top 30 cm) to further investigate nutrient removal from grey water. Operating the two filter columns in series at a HLR of 20 cm/day resulted in a better effluent quality than at a higher (40 cm/day) HLR. The COD removal efficiencies by filter columns 1 and 2 in series amounted to 90% and 84% at HLR of 20 cm/day and 40 cm/day, respectively. TOC and DOC removal efficiency amounted to 77% and 71% at a HLR of 20 cm/day, but decreased to 72% and 67% at a HLR of 40 cm/day, respectively. The highest log removal of Escherichia coli, Salmonella sp. and total coliforms amounted to 3.68, 3.50 and 3.95 at a HLR of 20 cm/day respectively. The overall removal of pollutants increased with infiltration depth, with the highest pollutant removal efficiency occurring in the top 15 cm layer. Grey water pre-treatment followed by double filtration using coarse and fine media has the potential to reduce the grey water pollution load in slum areas by more than 60%. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. ACTINIDE REMOVAL PROCESS SAMPLE ANALYSIS, CHEMICAL MODELING, AND FILTRATION EVALUATION

    Energy Technology Data Exchange (ETDEWEB)

    Martino, C.; Herman, D.; Pike, J.; Peters, T.

    2014-06-05

    Filtration within the Actinide Removal Process (ARP) currently limits the throughput in interim salt processing at the Savannah River Site. In this process, batches of salt solution with Monosodium Titanate (MST) sorbent are concentrated by crossflow filtration. The filtrate is subsequently processed to remove cesium in the Modular Caustic Side Solvent Extraction Unit (MCU) followed by disposal in saltstone grout. The concentrated MST slurry is washed and sent to the Defense Waste Processing Facility (DWPF) for vitrification. During recent ARP processing, there has been a degradation of filter performance manifested as the inability to maintain high filtrate flux throughout a multi-batch cycle. The objectives of this effort were to characterize the feed streams, to determine if solids (in addition to MST) are precipitating and causing the degraded performance of the filters, and to assess the particle size and rheological data to address potential filtration impacts. Equilibrium modelling with OLI Analyzer{sup TM} and OLI ESP{sup TM} was performed to determine chemical components at risk of precipitation and to simulate the ARP process. The performance of ARP filtration was evaluated to review potential causes of the observed filter behavior. Task activities for this study included extensive physical and chemical analysis of samples from the Late Wash Pump Tank (LWPT) and the Late Wash Hold Tank (LWHT) within ARP as well as samples of the tank farm feed from Tank 49H. The samples from the LWPT and LWHT were obtained from several stages of processing of Salt Batch 6D, Cycle 6, Batch 16.

  3. Graphite beds for coolant filtration at high temperature

    International Nuclear Information System (INIS)

    Heathcock, R.E.; Lacy, C.S.

    1978-01-01

    High temperature filtration will be provided for new Ontario Hydro CANDU heat transport systems. Filtration has been shown to effectively reduce the concentration of circulating corrosion products in our heat transport systems, hence, minimizing the processes of activity transport. This paper will present one option we have for this application; Deep Bed Granular Graphite Filters. The filter system is described by discussing pertinent aspects of its development programme. The compatibility of the filter and the heat transport coolant are demonstrated by results from loop tests, both out- and in-reactor, and by subsequent results from a large filter installation in the NPD NGS heat transport system. (author)

  4. Pathogen filtration to control plant disease outbreak in greenhouse production

    Science.gov (United States)

    Jeon, Sangho; Krasnow, Charles; Bhalsod, Gemini; Granke, Leah; Harlan, Blair; Hausbeck, Mary; Zhang, Wei

    2016-04-01

    Previous research has been extensively focused on understanding the fate and transport of human microbial pathogens in soil and water environments. However, little is known about the transport of plant pathogens, although these pathogens are often found in irrigation waters and could cause severe crop damage and economical loss. Water mold pathogens including Phytophthora spp. and Pythium spp. are infective to a wide range of vegetable and floriculture crops, and they are primarily harbored in soils and disseminated through water flow. It is challenging to control these pathogens because they often quickly develop resistance to many fungicides. Therefore, this multi-scale study aimed to investigate physical removal of plant pathogens from water by filtration, thus reducing the pathogen exposure risks to crops. In column-scale experiments, we studied controlling factors on the transport and retention of Phytophthora capsici zoospores in saturated columns packed with iron oxide coated-sand and uncoated-sand under varying solution chemistry. Biflagellate zoospores were less retained than encysted zoospores, and lower solution pH and greater iron oxide content increased the retention of encysted zoospores. These results provided insights on environmental dispersal of Phytophthora zoospores in natural soils as well as on developing cost-effective engineered filtration systems for pathogen removal. Using small-scale greenhouse filtration systems, we further investigated the performance of varying filter media (i.e., granular sand, iron oxide coated ceramic porous media, and activated carbon) in mitigating disease outbreaks of Phytophthora and Pythium for greenhouse-grown squash and poinsettia, respectively, in comparison with fungicide treatment. For squash, filtration by iron oxide coated media was more effective in reducing the Phytophthora infection, comparing to sand filtration and fungicide application. For poinsettia, sand filtration performed better in controlling

  5. Clinical dehydration and glomerular filtration rate in acute paediatric gastroenteritis.

    Science.gov (United States)

    Milani, Gregorio P; Fossali, Emilio F; Perri, Alessandra; Vettori, Arianna; Grillo, Paolo; Agostoni, Carlo

    2013-08-01

    To evaluate changes in glomerular filtration rate in acute gastroenteritis. The correlation between two clinical diagnostic scales and glomerular filtration rate has been investigated in 113 children with acute gastroenteritis in a paediatric emergency setting. A significant reduction of GFR was found in 10% children less than, and 5% children higher than, 2 years of age with acute gastroenteritis. The differences observed as for risk of renal hypoperfusion suggests to consider the age of children as an important determinant to consider the dehydration status in acute gastroenteritis. ©2013 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  6. Simulation of impaction filtration of aerosol droplets in porous media

    OpenAIRE

    Ghazaryan, L.; Lopez Penha, D.J.; Geurts, Bernardus J.; Stolz, S.; Stolz, Steffen; Winkelmann, Christoph; Pereira, J.C.F; Sequeira, A.; Pereira, J.M.C.

    2010-01-01

    We report on the development of a method to simulate from first principles the particle filtration efficiency of filters that are composed of structured porous media. We assume that the ratio of particle density to the fluid density is high. We concentrate on the motion of the particles in a laminar flow and quantify the role of inertial effects on the filtration of an ensemble of particles. We adopt the Euler-Lagrange approach, distinguishing a flow field in which the motion of a large numbe...

  7. Removal of heavy metals and radionuclides by seeded magnetic filtration

    International Nuclear Information System (INIS)

    Bibler, J.P.; Norrell, G.; Hemmings, R.L.; Bradbury, D.; Dunn, M.J.; Kalinauskas, G.L.

    1991-01-01

    Removal of traces of heavy metal or radionuclide contamination from solution at high flow rate presents a considerable technical challenge. Low flow methods of treatment such as particle gravity settling require expensive large volume equipment, whereas traditional methods of filtration can cause significant energy costs. Magnetic filtration can be used to provide a low cost method of solid-liquid separation at high flow rate, provided contaminants can be selectively bound to a magnetic solid particle. This paper describes the use of such selective magnetic particles made up of inorganic particles coupled with organic polymers

  8. Horizontal-belt filtration at Randfontein Estates Mine

    International Nuclear Information System (INIS)

    Blendulf, K.A.G.; Everett, D.J.

    1979-01-01

    The paper describes tests on horizontal-belt filters for the filtration of gold and uranium. The promising results led to the installation of 17 such filters (ten of them 120 m 2 in size) in the mine's metallurgical plants, and their operation is discussed. Although several problems were encountered both in operation and maintenance, it is concluded that, with correct operation and suitable filter cloths, exceptionally good metallurgical recoveries can be achieved at filtration rates twice to three times higher than those on rotary filters [af

  9. Low-cost multi-stage filtration enhanced by coagulation-flocculation in upflow gravel filtration

    Directory of Open Access Journals (Sweden)

    L. D. Sánchez

    2012-12-01

    Full Text Available This paper assesses the operational and design aspects of coagulation and flocculation in upflow gravel filters (CF-UGF in a multi-stage filtration (MSF plant. This study shows that CF-UGF units improve the performance of MSF considerably, when the system operates with turbidity above 30 NTU. It strongly reduces the load of particulate material before the water enters in the slow sand filters (SSF and therewith avoids short filter runs and prevents early interruption in SSF operations. The removal efficiency of turbidity in the CF-UGF with coagulant was between 85 and 96%, whereas the average efficiency without coagulant dosing was 46% (range: 21–76%. Operating with coagulant also improves the removal efficiency for total coliforms, E-coli and HPC. No reduction was observed in the microbial activity of the SSF, no obstruction of the SSF bed was demonstrated and SSF runs were maintained between 50 and 70 days for a maximum head loss of 0.70 m. The most important advantage is the flexibility of the system to operate with and without coagulant according to the influent turbidity. It was only necessary for 20% of the time to operate with the coagulant. The CF-UGF unit represented 7% of total construction costs and the O&M cost for the use of coagulant represented only 0.3%.

  10. Silica reinforced triblock copolymer gels

    DEFF Research Database (Denmark)

    Theunissen, E.; Overbergh, N.; Reynaers, H.

    2004-01-01

    The effect of silica and polymer coated silica particles as reinforcing agents on the structural and mechanical properties of polystyrene-poly(ethylene/butylene)-polystyrene (PS-PEB-PS) triblock gel has been investigated. Different types of chemically modified silica have been compared in order...

  11. Effect of Proteolytic Modification on Texture and Mastication of Heat‐Treated Egg White Gels

    Science.gov (United States)

    Funaki, Junko; Minami, Michiko; Abe, Sachie; Ueda, Reiko; Eto, Wakako; Kugino, Kenji; Kugino, Mutsuko; Abe, Keiko; Toko, Kiyoshi

    2016-01-01

    Abstract Raw egg white undergoes sol–gel transition by heat treatment, which changes it to an elastic gel. Here, protease treatment to render a new texture to heated egg white gel was applied. Protease‐treated gels exhibited ductile flow without obvious rupture points. Transmission electron microscopy analysis showed that in protease‐treated gels, protein aggregates were distributed more homogeneously compared with that observed in the untreated control, probably because ovalbumin was digested into small peptides as revealed by SDS‐PAGE. The properties of the gel were evaluated by sensory tests and by measuring the movement of the masseter muscle, using surface electromyography. Results showed that maximum bite force and mastication duration were decreased for the protease‐treated gels, which were evaluated as being softer, smoother, less elastic and better textured. Overall, our results indicate that protease‐treated egg white gel has superior qualities and is easier to swallow than the untreated gel. Practical Applications In the food industry, the use of egg white is limited compared with that of egg yolk and whole eggs. In this study, we performed protease treatment to generate a new food material with smoother and softer texture compared with heat treated egg white. Our findings may expand the consumption of egg white, which can be consumed by people with mastication and swallowing disorders, and reduce the waste of egg white as a surplus product. PMID:28239213

  12. The effect of residual water on antacid properties of sucralfate gel dried by microwaves.

    Science.gov (United States)

    Gainotti, Alessandro; Losi, Elena; Colombo, Paolo; Santi, Patrizia; Sonvico, Fabio; Baroni, Daniela; Massimo, Gina; Colombo, Gaia; Del Gaudio, Pasquale

    2006-03-01

    The aim of this work was to study the acid neutralization characteristics of microwave-dried sucralfate gel in relation to the water content and physical structure of the substance. Several dried sucralfate gels were compared with humid sucralfate gel and sucralfate nongel powder in terms of neutralization rate and buffering capacity. Humid sucralfate gel and microwave-dried gel exhibited antacid effectiveness. In particular, the neutralization rate of dried gel powders was inversely related to the water content: as the water content of dried powders decreased, the acid reaction rate linearly increased. The relationship was due to the different morphology of dried sucralfate gels. In fact, the porosity of the dried samples increased with the water reduction. However, the acid neutralization equivalent revealed that the dried sucralfate gel became more resistant to acid attack in the case of water content below 42%. Then, the microwave drying procedure had the opposite effect on the reactivity of the aluminum hydroxide component of dried sucralfate gel powders, since the rate of the reaction increased whereas the buffering capacity decreased as the amount of water was reduced.

  13. Functional principal component analysis of glomerular filtration rate curves after kidney transplant.

    Science.gov (United States)

    Dong, Jianghu J; Wang, Liangliang; Gill, Jagbir; Cao, Jiguo

    2017-01-01

    This article is motivated by some longitudinal clinical data of kidney transplant recipients, where kidney function progression is recorded as the estimated glomerular filtration rates at multiple time points post kidney transplantation. We propose to use the functional principal component analysis method to explore the major source of variations of glomerular filtration rate curves. We find that the estimated functional principal component scores can be used to cluster glomerular filtration rate curves. Ordering functional principal component scores can detect abnormal glomerular filtration rate curves. Finally, functional principal component analysis can effectively estimate missing glomerular filtration rate values and predict future glomerular filtration rate values.

  14. 21 CFR 866.4900 - Support gel.

    Science.gov (United States)

    2010-04-01

    ... IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents § 866.4900 Support gel. (a) Identification. A support gel for clinical use is a device that consists of an agar or agarose preparation that...

  15. Assessment of endophytic fungi cultural filtrate on soybean seed ...

    African Journals Online (AJOL)

    Soybean seeds have high amount of isoflavones but its germination is often confronted with a variety of environmental problems resulting in low germination rate and growth. To overcome this in eco-friendly manner, we investigated the influence of cultural filtrate (CF) of gibberellins-producing endophytic fungi on soybean ...

  16. Alternative filtration testing program: Pre-evaluation of test results

    International Nuclear Information System (INIS)

    Georgeton, G.K.; Poirier, M.R.

    1990-01-01

    Based on results of testing eight solids removal technologies and one pretreatment option, it is recommended that a centrifugal ultrafilter and polymeric ultrafilter undergo further testing as possible alternatives to the Norton Ceramic filters. Deep bed filtration should be considered as a third alternative, if a backwashable cartridge filter is shown to be inefficient in separate testing

  17. Iron behavior in the ozonation and filtration of groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Sallanko, J.; Lakso, E.; Ropelinen, J. [University of Oulu, Oulu (Finland)

    2006-08-15

    In Finnish groundwater, the main substances that require treatment are iron and manganese. In addition to this, groundwaters are soft and acidic. Iron removal is usually relatively effective by oxidizing dissolved iron into an insoluble form, either by aeration or chemical oxidation and removing the formed precipitate by sand filtration. Sometimes, if the untreated water contains high amounts of organic matter, problems may arise for iron removal. In Finland, it is quite common that groundwater contains high levels of both iron and natural organic matter, mainly as humic substances. The groundwater of the Kukkala intake plant in Liminka has been found to be problematic, due to its high level of natural organic matter. This research studied the removal of iron from this water by means of oxidation with ozone and filtration. While the oxidation of iron by ozone was rapid, the precipitate particles formed were small, and thus could not be removed by sand and anthracite filtration, and the iron residue in the treated water was more than 2 mg L{sup -1}. And while the filtration was able to remove iron well without the feed of ozone, the iron residue in the treated water was only 0.30 mg L{sup -1}. In this case, iron was led to the filter in a bivalent dissolved form. So, the result of iron removal was the best when the sand/anthracite filter functioned largely as an adsorption filter.

  18. The impact of metallic filter media on HEPA filtration

    International Nuclear Information System (INIS)

    Chadwick, Chris; Kaufman, Seth

    2006-01-01

    Traditional HEPA filter systems have limitations that often prevent them from solving many of the filtration problems in the nuclear industry; particularly in applications where long service or storage life, high levels of radioactivity, dangerous decomposition products, chemical aggression, organic solvents, elevated operating temperatures, fire resistance and resistance to moisture are issues. This paper addresses several of these matters of concern by considering the use of metallic filter media to solve HEPA filtration problems ranging from the long term storage of transuranic waste at the WIPP site, spent and damaged fuel assemblies, in glove box ventilation and tank venting to the venting of fumes at elevated temperatures from incinerators, vitrification processes and conversion and sintering furnaces as well as downstream of iodine absorbers in gas cooled reactors in the UK. The paper reviews the basic technology, development, performance characteristics and filtration efficiency, flow versus differential pressure, cleanability and costs of sintered metal fiber in comparison with traditional resin bonded glass fiber filter media and sintered metal powder filter media. Examples of typical filter element and system configurations and applications will be presented The paper will also address the economic case for installing self cleaning pre-filtration, using metallic media, to recover the small volumes of dust that would otherwise blind large volumes of final disposable HEPA filters, thus presenting a route to reduce ultimate disposal volumes and secondary waste streams. (authors)

  19. Evaluation of condensate filtration technologies in fossil plants

    Energy Technology Data Exchange (ETDEWEB)

    D' Angelo, Philip J. [JoDan Technologies Ltd., Glen Mills, PA (United States)

    2009-09-15

    Long-term protection of electric power generating station boilers depends upon the quality of their feedwater chemistry with respect to the transport and deposition of corrosion products to the boilers from various corrosion sources in the plant's condensate and feedwater cycle. It is in the utility's best interests to expand their programs to include ways to reduce the transport of corrosion products, especially those that occur during plant start-ups. Condensate filtration is a strategy employed by some utilities with demonstrable results in minimizing corrosion product transport and achieving a return on their investment. This paper provides a comparative review of available condensate filtration technologies as well as performance data from fossil plants with the new large diameter high flow filtration systems. Additionally, the paper identifies critical parameters to consider before installation as well as the necessity for agreement between utilities and suppliers on common filtration terminology definitions, to insure an ''apple-to-apple'' basis when comparing a system or technology from more than one supplier. (orig.)

  20. Successful Treatment Of Homozygous Familial Hypercholesterolemia Using Cascade Filtration Plasmapheresis

    Directory of Open Access Journals (Sweden)

    Fatih Kardas

    2012-12-01

    Full Text Available OBJECTIVE: The aim of our study is to discuss the efficacy of low-density lipoprotein-cholesterol (LDL-C apheresis procedure using the cascade filtration system for pediatric patients with homozygous familial hypercholesterolemia (FH, and to clarify the adverse effects and difficulties. METHODS: LDL apheresis using the cascade filtration system was performed in 3 pediatric patients with homozygous FH. In total, 120 apheresis sessions were performed for all patients. RESULTS: Cascade filtration therapy significantly reduced the mean LDL-C values from 418 ± 62 mg/dl to 145 ± 43 mg/dl (p<0.05. We determined an acute mean reduction in the plasma levels of total cholesterol (57.9%, LDL cholesterol (70.8%, and high-density lipoprotein (HDL cholesterol (40.7%. Treatments were well tolerated. The most frequent clinical adverse effects were hypotension in 3 sessions (2.5%, chills/feeling cold (1.7% in 2 sessions, and nausea and vomiting in 3 sessions (2.5%. CONCLUSION: Our experience with three patients using the cascade filtration system were, good clinical outcomes, laboratory findings, safety of usage, minor adverse effects and technical problems.

  1. Removal of Brettanomyces bruxellensis from red wine using membrane filtration

    Science.gov (United States)

    While sulfites help limit growth of the spoilage yeast, Brettanomyces, SO2 has been reported to decrease cell size, thereby potentially decreasing the porosities of filtration membranes required for removal. B. bruxellensis strains B1b and F3 were inoculated into red wines and after 12 days, half th...

  2. Polymer aids for settling and filtration of oil sands tailings

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering; Energy Resources Conservation Board, Calgary, AB (Canada). Oil Sands Section; Xu, Z.; Masliyah, J.H. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering

    2008-07-01

    Oil sand tailings are segregated into coarse and fine tailings. High volumes of toxic fluids and tailings are created in the process. Tailings ponds are an environmental risk with high operating and maintenance costs. Current commercial technologies uses chemical additions to create recycled water and composite tailings (CT). Researchers are now investigating centrifuged and dry mature fine tailings (MFT). Filtration processes with flocculants are used to separate the tailings into warm recycle water and dried cakes that can be used in reclamation processes. Studies are being conducted to find a polymer than can effectively flocculate and filter whole oil sands tailings. The filtration procedure uses pressure to produce released water. Polymers include magnafloc and Al-PAM polymer concentrations are used in slurry masses. Tests have been conducted to determine the settling rates of the polymers. The tests showed that Al-PAM filtered the tailings effectively. Paraffinic froth treatment tests have also been conducted to determine settling rates. A cake produced with froth treatment tailings of Al-PAM 400 ppm had a water content 42.5 wt per cent. The tests showed that while Magnafloc 1011 is a good settling aid, but a poor filtration addition. Al-PAM aided in both the flocculation and filtration processes. Higher Al-PAM dosages are needed for froth treatment tailings processes. It was concluded that dry cakes are produced with the addition of Al-PAM. tabs., figs.

  3. Radioactive slurry waste treatment (2) - surfactants dose effects on filtration

    International Nuclear Information System (INIS)

    Jung, K. H.; Park, S. K.; Jung, W. S.; Baek, S. T.; Jung, K. J.

    1999-01-01

    The influence of anionic flocculants on the dewatering of radioactive slurries has been investigated in a laboratory-scale vacuum filtration unit. Simultaneously the influence of certain surfactants has also been investigated. Test results show that the flocculated filter cake generally contains higher residual water than the unflocculated cake. The non-ionic surfactant was effective in reducing the moisture content of the cake

  4. Initial testing of electrospun nanofibre filters in water filtration ...

    African Journals Online (AJOL)

    The aim of this study was to evaluate the use of nanofibre microfiltration membranes, spun by an innovative electrospinning technique, in water filtration applications. As such, this study bridges the gap between developments in electrospinning techniques for the production of flat-sheet membranes and the application of ...

  5. Cross-flow micro-filtration using ceramic membranes

    International Nuclear Information System (INIS)

    Thern, Gerardo G.; Marajofsky, Adolfo; Rossi, Federico; La Gamma, Ana M.; Chocron, Mauricio

    2004-01-01

    Pressurized Heavy Water Reactors have a system devoted to the purification and upgrading of the collected heavy water leaks. The purification train is fed with different degradation ratios (D 2 O/H 2 O), activities and impurities. The water is distilled in a packed bed column filled with a mesh type packing. With the purpose of minimizing the column stack corrosion, the water is pre-treated in a train consisting on an activated charcoal bed-strong cationic-anionic resin and a final polishing anionic bed resin. Traces of oils are retained by the charcoal bed but some of them pass through and could be responsible for the resins fouling. The process of micro filtration using ceramic materials is particularly applied to the treatment of waters with oil micro droplets. We describe the development stages of single and double layer filtration ceramic tubes, their characterization and the adaptation to test equipment. The efficiency was evaluated by means of tangential ('cross-flow') filtration of aqueous solutions containing dodecane at the micrograms per ml concentration level. This compound simulates the properties of a typical oil contaminant. A 100-fold reduction in the amount of dodecane in water was observed after the filtration treatment. (author)

  6. Reduced glomerular filtration rate as a predictor of coronary artery ...

    African Journals Online (AJOL)

    Tarek A. Ghonemy

    2016-07-09

    Jul 9, 2016 ... Internal Medicine Department, Nephrology Unit, Zagazig University ... glomerular filtration rate (eGFR) and risk of coronary artery disease ... ing of eGFR may have a pivotal role in early detection and management of CAD in those types of ..... position statement from kidney disease improving global out-.

  7. Alternative filtration testing program: Pre-evaluation of test results

    Energy Technology Data Exchange (ETDEWEB)

    Georgeton, G.K.; Poirier, M.R.

    1990-09-28

    Based on results of testing eight solids removal technologies and one pretreatment option, it is recommended that a centrifugal ultrafilter and polymeric ultrafilter undergo further testing as possible alternatives to the Norton Ceramic filters. Deep bed filtration should be considered as a third alternative, if a backwashable cartridge filter is shown to be inefficient in separate testing.

  8. Experimental and Numerical Study of Ceramic Foam Filtration

    Science.gov (United States)

    Laé, E.; Duval, H.; Rivière, C.; Le Brun, P.; Guillot, J.-B.

    Ceramic foam filtration is widely used to enable removal of non metallic inclusions from liquid aluminium. Its performances have been largely studied in the literature and some discrepancies remain amongst the published results. Consequently, a research program was deployed to evaluate the performances of a range of ceramic foam filters used under various conditions and to understand the inclusions capture mechanisms.

  9. Batch cooling crystallization and pressure filtration of sulphathiazole

    DEFF Research Database (Denmark)

    Häkkinen, Antti; Pöllänen, Kati; Karjalainen, Milja

    2005-01-01

    Currently there is a great interest in new process analytical approaches to increase the process understanding of pharmaceutical unit operations. In the present study, the influence of the solvent composition on the material properties and, further, on the filtration characteristics, of different...

  10. Complexant Identification in Hanford Waste Simulant Sr/TRU Filtrate

    International Nuclear Information System (INIS)

    Bannochie, C.J.

    2003-01-01

    This project was designed to characterize the available multidentate ligand species and metal ion complexes of iron, strontium and manganese formed with the parent chelators, complexing agents and their fragment products. Complex identification was applied to AN-102 and AN-107 filtrate simulants for Hanford waste after an oxidation reaction with sodium permanganate to create a freshly precipitated manganese dioxide solid for adsorption of transuranic elements. Separation efficiency of different ligands was investigated based on the exchange capability of different ion exchange and ion exclusion analytical columns including Dionex IonPac AS-5A, AS-10, AS-11 and AS-6. The elution programs developed with different mobile phase concentrations were based on the change in the effective charge of the anionic species and therefore the retention on the stationary phase. In the present work, qualitative and quantitative assessments of multidentate ligands were investigated. Identification methods for the metal ion complexes responsible for solubilizing Fe, Mn and Sr were applied to aged and fresh simulant waste filtrates. Although concentration measurements of both fresh and 3-week aged filtrates showed that the degradation process occurs mainly due to the harsh chemical environment, it was found that the concentration of iron and manganese did not increase, within the error of the analytical measurements, after three weeks when compared with fresh filtrate

  11. Separation of nanoparticles: Filtration and scavenging from waste incineration plants.

    Science.gov (United States)

    Förster, Henning; Thajudeen, Thaseem; Funk, Christine; Peukert, Wolfgang

    2016-06-01

    Increased amounts of nanoparticles are applied in products of everyday life and despite material recycling efforts, at the end of their life cycle they are fed into waste incineration plants. This raises the question on the fate of nanoparticles during incineration. In terms of environmental impact the key question is how well airborne nanoparticles are removed by separation processes on their way to the bag house filters and by the existing filtration process based on pulse-jet cleanable fibrous filter media. Therefore, we investigate the scavenging and the filtration of metal nanoparticles under typical conditions in waste incineration plants. The scavenging process is investigated by a population balance model while the nanoparticle filtration experiments are realized in a filter test rig. The results show that depending on the particle sizes, in some cases nearly 80% of the nanoparticles are scavenged by fly ash particles before they reach the bag house filter. For the filtration step dust cakes with a pressure drop of 500Pa or higher are found to be very effective in preventing nanoparticles from penetrating through the filter. Thus, regeneration of the filter must be undertaken with care in order to guarantee highly efficient collection of particles even in the lower nanometre size regime. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Successful treatment of homozygous familial hypercholesterolemia using cascade filtration plasmapheresis.

    Science.gov (United States)

    Kardaş, Fatih; Cetin, Aysun; Solmaz, Musa; Büyükoğlan, Rüksan; Kaynar, Leylagül; Kendirci, Mustafa; Eser, Bülent; Unal, Ali

    2012-12-01

    The aim of this study was to report the efficacy of low-density lipoprotein cholesterol (LDL-C) apheresisusing a cascade filtration system in pediatric patients with homozygous familial hypercholesterolemia (FH), and toclarify the associated adverse effects and difficulties. LDL-C apheresis using a cascade filtration system was performed in 3 pediatric patientswith homozygous FH; in total, 120 apheresis sessions were performed. Cascade filtration therapy significantly reduced the mean LDL-C values from 418 ± 62 mg/dL to 145 ± 43 mg/dL (p= 0.011). We observed an acute mean reduction in the plasma level of total cholesterol (57.9%), LDL-C (70.8%),and high-density lipoprotein cholesterol (HDL-C) (40.7%). Treatments were well tolerated. The most frequent clinicaladverse effects were hypotension in 3 sessions (2.5%), chills (1.7%) in 2 sessions, and nausea/vomiting in 3 sessions(2.5%). Our experience using the cascade filtration system with 3 patients included good clinical outcomes andlaboratory findings, safe usage, and minor adverse effects and technical problems. None declared.

  13. Simulation of impaction filtration of aerosol droplets in porous media

    NARCIS (Netherlands)

    Ghazaryan, L.; Lopez Penha, D.J.; Geurts, Bernardus J.; Stolz, S.; Stolz, Steffen; Winkelmann, Christoph; Pereira, J.C.F; Sequeira, A.; Pereira, J.M.C.

    2010-01-01

    We report on the development of a method to simulate from first principles the particle filtration efficiency of filters that are composed of structured porous media. We assume that the ratio of particle density to the fluid density is high. We concentrate on the motion of the particles in a laminar

  14. Surface patterning of polymeric separation membranes and its influence on the filtration performance

    Science.gov (United States)

    Maruf, Sajjad

    Polymeric membrane based separation technologies are crucial for addressing the global issues such as water purification. However, continuous operations of these processes are often hindered by fouling which increases mass transport resistance of the membrane to permeation and thus the energy cost, and eventually replacement of the membrane in the system. In comparison to other anti-fouling strategies, the use of controlled surface topography to mitigate fouling has not been realized mainly due to the lack of methods to create targeted topography on the porous membrane surface. This thesis aims to develop a new methodology to create surface-patterned polymeric separation membrane to improve their anti-fouling characteristics during filtration. First, successful fabrication of sub-micron surface patterns directly on a commercial ultrafiltration (UF) membrane surface using nanoimprint lithographic (NIL) technique was demonstrated. Comprehensive filtration studies revealed that the presence of these sub-micron surface patterns mitigates not only the onset of colloidal particle deposition, but also lowers the rate of growth of cake layer after initial deposition, in comparison with un-patterned membranes. The anti-fouling effects were also observed for model protein solutions. Staged filtration experiments, with backwash cleaning, revealed that the permeate flux of the patterned membrane after protein fouling was considerably higher than that of the pristine or un-patterned membrane. In addition to the surface-patterning of UF membranes, successful fabrication of a surface-patterned thin film composite (TFC) membrane was shown for the first time. A two-step fabrication process was carried out by (1) nanoimprinting a polyethersulfone (PES) support using NIL, and (2) forming a thin dense film atop the PES support via interfacial polymerization (IP). Fouling experiments suggest that the surface patterns alter the hydrodynamics at the membrane-feed interface, which is

  15. Yield stress determination of a physical gel

    DEFF Research Database (Denmark)

    Hvidt, Søren

    2013-01-01

    Pluronic F127 solutions form gels in water with high elastic moduli. Pluronic gels can, however, only withstand small deformations and stresses. Different steady shear and oscillatory methods traditionally used to determine yield stress values are compared. The results show that the yield stresses...... values of these gels depend on test type and measurement time, and no absolute yield stress value can be determined for these physical gels....

  16. Definition of purified enzyme-linked immunosorbent assay antigens from the culture filtrate protein of Mycobacterium bovis by proteomic analysis.

    Science.gov (United States)

    Cho, Yun Sang; Lee, Sang-Eun; Ko, Young Joon; Cho, Donghee; Lee, Hyang Shim; Hwang, Inyeong; Nam, Hyangmi; Heo, Eunjung; Kim, Jong Man; Jung, Sukchan

    2009-01-01

    Enzyme-linked immunosorbent assay (ELISA) has been developed as the ancillary diagnosis of bovine tuberculosis at ante-mortem to overcome the disadvantages of intradermal skin test. In this study, the antigenic proteins were purified, applied to bTB ELISA, and identified through proteomic analysis. Culture filtrate protein of Mycobacterium bovis was fractionated by MonoQ column chromatography, and examined the antigenicity by immunoblotting. The antigenic 20 kDa protein was in-gel digested and identified the antigenome by LTQ mass spectrometer and peptide match fingerprinting, which were MPB64, MPB70, MPB83, Fas, Smc, Nrp, RpoC, Transposase, LeuA, and MtbE. The 20 kDa protein exhibited the highest antigenicity to bTB positive cattle in ELISA and would be useful for bTB serological diagnosis.

  17. Filtration behavior of casein glycomacropeptide (CGMP) in an enzymatic membrane reactor: fouling control by membrane selection and threshold flux operation

    DEFF Research Database (Denmark)

    Luo, Jianquan; Morthensen, Sofie Thage; Meyer, Anne S.

    2014-01-01

    . In this study, the filtration performance and fouling behavior during ultrafiltration (UF) of CGMP for the enzymatic production of 3′-sialyllactose were investigated. A 5kDa regenerated cellulose membrane with high anti-fouling performance, could retain CGMP well, permeate 3′-sialyllactose, and was found...... to be the most suitable membrane for this application. Low pH increased CGMP retention but produced more fouling. Higher agitation and lower CGMP concentration induced larger permeate flux and higher CGMP retention. Adsorption fouling and pore blocking by CGMP in/on membranes could be controlled by selecting...... a highly hydrophilic membrane with appropriate pore size. Operating under threshold flux could minimize the concentration polarization and cake/gel/scaling layers, but might not avoid irreversible fouling caused by adsorption and pore blocking. The effects of membrane properties, pH, agitation and CGMP...

  18. Cake filtration modeling: Analytical cake filtration model and filter medium characterization

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Michael

    2008-05-15

    Cake filtration is a unit operation to separate solids from fluids in industrial processes. The build up of a filter cake is usually accompanied with a decrease in overall permeability over the filter leading to an increased pressure drop over the filter. For an incompressible filter cake that builds up on a homogeneous filter cloth, a linear pressure drop profile over time is expected for a constant fluid volume flow. However, experiments show curved pressure drop profiles, which are also attributed to inhomogeneities of the filter (filter medium and/or residual filter cake). In this work, a mathematical filter model is developed to describe the relationship between time and overall permeability. The model considers a filter with an inhomogeneous permeability and accounts for fluid mechanics by a one-dimensional formulation of Darcy's law and for the cake build up by solid continuity. The model can be solved analytically in the time domain. The analytic solution allows for the unambiguous inversion of the model to determine the inhomogeneous permeability from the time resolved overall permeability, e.g. pressure drop measurements. An error estimation of the method is provided by rewriting the model as convolution transformation. This method is applied to simulated and experimental pressure drop data of gas filters with textile filter cloths and various situations with non-uniform flow situations in practical problems are explored. A routine is developed to generate characteristic filter cycles from semi-continuous filter plant operation. The model is modified to investigate the impact of non-uniform dust concentrations. (author). 34 refs., 40 figs., 1 tab

  19. Physical Properties of Silicone Gel Breast Implants.

    Science.gov (United States)

    Jewell, Mark L; Bengtson, Bradley P; Smither, Kate; Nuti, Gina; Perry, TracyAnn

    2018-04-28

    Surgical applications using breast implants are individualized operations to fill and shape the breast. Physical properties beyond shape, size, and surface texture are important considerations during implant selection. Compare form stability, gel material properties, and shell thickness of textured shaped, textured round, and smooth round breast implants from 4 manufacturers: Allergan, Mentor, Sientra, and Establishment Labs through bench testing. Using a mandrel height gauge, form stability was measured by retention of dimensions on device movement from a horizontal to vertical supported orientation. Dynamic response of gel material (gel cohesivity, resistance to gel deformation, energy absorption) was measured using a synchronized target laser following application of graded negative pressure. Shell thickness was measured using digital thickness gauge calipers. Form stability, gel material properties, and shell thickness differed across breast implants. Of textured shaped devices, Allergan Natrelle 410 exhibited greater form stability than Mentor MemoryShape and Sientra Shaped implants. Allergan Inspira round implants containing TruForm 3 gel had greater form stability, higher gel cohesivity, greater resistance to gel deformation, and lower energy absorption than those containing TruForm 2 gel and in turn, implants containing TruForm 1 gel. Shell thickness was greater for textured versus smooth devices, and differed across styles. Gel cohesivity, resistance to gel deformation, and energy absorption are directly related to form stability, which in turn determines shape retention. These characteristics provide information to aid surgeons choosing an implant based on surgical application, patient tissue characteristics, and desired outcome.

  20. Filtration effectiveness of HVAC systems at near-roadway schools.

    Science.gov (United States)

    McCarthy, M C; Ludwig, J F; Brown, S G; Vaughn, D L; Roberts, P T

    2013-06-01

    Concern for the exposure of children attending schools located near busy roadways to toxic, traffic-related air pollutants has raised questions regarding the environmental benefits of advanced heating, ventilation, and air-conditioning (HVAC) filtration systems for near-road pollution. Levels of black carbon and gaseous pollutants were measured at three indoor classroom sites and at seven outdoor monitoring sites at Las Vegas schools. Initial HVAC filtration systems effected a 31-66% reduction in black carbon particle concentrations inside three schools compared with ambient air concentrations. After improved filtration systems were installed, black carbon particle concentrations were reduced by 74-97% inside three classrooms relative to ambient air concentrations. Average black carbon particle concentrations inside the schools with improved filtration systems were lower than typical ambient Las Vegas concentrations by 49-96%. Gaseous pollutants were higher indoors than outdoors. The higher indoor concentrations most likely originated at least partially from indoor sources, which were not targeted as part of this intervention. Recent literature has demonstrated adverse health effects in subjects exposed to ambient air near major roadways. Current smart growth planning and infill development often require that buildings such as schools are built near major roadways. Improving the filtration systems of a school's HVAC system was shown to decrease children's exposure to near-roadway diesel particulate matter. However, reducing exposure to the gas-phase air toxics, which primarily originated from indoor sources, may require multiple filter passes on recirculated air. © 2012 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

  1. Impacts of extreme flooding on riverbank filtration water quality.

    Science.gov (United States)

    Ascott, M J; Lapworth, D J; Gooddy, D C; Sage, R C; Karapanos, I

    2016-06-01

    Riverbank filtration schemes form a significant component of public water treatment processes on a global level. Understanding the resilience and water quality recovery of these systems following severe flooding is critical for effective water resources management under potential future climate change. This paper assesses the impact of floodplain inundation on the water quality of a shallow aquifer riverbank filtration system and how water quality recovers following an extreme (1 in 17 year, duration >70 days, 7 day inundation) flood event. During the inundation event, riverbank filtrate water quality is dominated by rapid direct recharge and floodwater infiltration (high fraction of surface water, dissolved organic carbon (DOC) >140% baseline values, >1 log increase in micro-organic contaminants, microbial detects and turbidity, low specific electrical conductivity (SEC) 400% baseline). A rapid recovery is observed in water quality with most floodwater impacts only observed for 2-3 weeks after the flooding event and a return to normal groundwater conditions within 6 weeks (lower fraction of surface water, higher SEC, lower DOC, organic and microbial detects, DO). Recovery rates are constrained by the hydrogeological site setting, the abstraction regime and the water quality trends at site boundary conditions. In this case, increased abstraction rates and a high transmissivity aquifer facilitate rapid water quality recoveries, with longer term trends controlled by background river and groundwater qualities. Temporary reductions in abstraction rates appear to slow water quality recoveries. Flexible operating regimes such as the one implemented at this study site are likely to be required if shallow aquifer riverbank filtration systems are to be resilient to future inundation events. Development of a conceptual understanding of hydrochemical boundaries and site hydrogeology through monitoring is required to assess the suitability of a prospective riverbank filtration

  2. Effect of hypothermic pulmonary artery flushing on capillary filtration coefficient.

    Science.gov (United States)

    Andrade, R S; Wangensteen, O D; Jo, J K; Tsai, M Y; Bolman, R M

    2000-07-27

    We previously demonstrated that surfactant dilution and inhibition occur immediately after pulmonary artery flushing with hypothermic modified Euro-Collins solution. Consequently, we speculated that increased capillary permeability contributed to these surfactant changes. To test this hypothesis, we evaluated the effects of hypothermic pulmonary artery flushing on the pulmonary capillary filtration coefficient (Kfc), and additionally performed a biochemical analysis of surfactant. We used a murine isolated, perfused lung model to measure the pulmonary capillary filtration coefficient and hemodynamic parameters, to determine the wet to dry weight ratio, and to evaluate surfactant by biochemical analysis of lung lavage fluid. We defined three study groups. In group I (controls), we harvested lungs without hypothermic pulmonary artery flushing, and measured Kfc immediately. In group II (in situ flush), we harvested lungs after hypothermic pulmonary artery flushing with modified Euro-Collins solution, and then measured Kfc. Experiments in groups I and II were designed to evaluate persistent changes in Kfc after pulmonary artery flushing. In group III (ex vivo flush), we flushed lungs ex vivo to evaluate transient changes in Kfc during hypothermic pulmonary artery flushing. Groups I and II did not differ significantly in capillary filtration coefficient and hemodynamics. Group II showed significant alterations on biochemical surfactant analysis and a significant increase in wet-to-dry weight ratio, when compared with group I. In group III, we observed a significant transient increase in capillary filtration coefficient during pulmonary artery flushing. Hypothermic pulmonary artery flushing transiently increases the capillary filtration coefficient, leads to an increase in the wet to dry weight ratio, and induces biochemical surfactant changes. These findings could be explained by the effects of hypothermic modified Euro-Collins solution on pulmonary capillary

  3. Phyllosilicates and Amorphous Gel in the Nakhlites

    Science.gov (United States)

    Hicks, L. J.; Bridges, J. C.; Gurman, S. J.

    2013-09-01

    Previous studies of the nakhlite martian meteorites have revealed hydrothermal minerals present within the fractures of the olivine minerals and the mesostasis. The olivine fractures of the Lafayette nakhlite reveal variations with initial deposits of siderite on the fracture walls, followed by crystalline phyllosilicates (smectite), and finishing with a rapidly cooled amorphous silicate gel within the central regions of the fractures. The mesostasis fractures of Lafayette also contain a crystalline phyllosilicate (serpentine). The amorphous gel is the most abundant secondary phase within the fractures of the other nakhlites [1, 2]. By studying nine nakhlite samples, including Lafayette, Governador Valadares, Nakhla, Y-000593, Y-000749, Miller-Range 03346, NWA 817, NWA 998, and NWA 5790, our aim is to constrain the identity of the phyllosilicate secondary phase minerals found throughout the nakhlite martian meteorites. This is achieved using methods including Electron Probe Micro-analysis (EPMA); X-ray Absorption Near-Edge Structure (Fe-K XANES) spectroscopy measured using Beamline I-18 at the Diamond Light Source synchrotron; and the use of Transmission Electron Microscopy (TEM) at the University of Leicester for High-Resolution (HR) imaging and Selected Area Electron Diffraction (SAED). BF studying nine nakhlite samples, including Lafayette, Governador Valadares, Nakhla, Y-000593, Y-000749, Miller-Range 03346, NWA 817, NWA 998, and NWA 5790, our aim is to constrain the identity of the phyllosilicate secondary phase minerals found throughout the nakhlite martian meteorites. This is achieved using methods including Electron Probe Micro-analysis (EPMA); X-ray Absorption Near-Edge Structure (Fe-K XANES) spectroscopy measured using Beamline I-18 at the Diamond Light Source synchrotron; and the use of Transmission Electron Microscopy (TEM) at the University of Leicester for High-Resolution (HR) imaging and Selected Area Electron Diffraction (SAED).

  4. Stochastic modeling of filtrate alkalinity in water filtration devices: Transport through micro/nano porous clay based ceramic materials

    Science.gov (United States)

    Clay and plant materials such as wood are the raw materials used in manufacture of ceramic water filtration devices around the world. A step by step manufacturing procedure which includes initial mixing, molding and sintering is used. The manufactured ceramic filters have numerous pores which help i...

  5. The gel electrophoresis markup language (GelML) from the Proteomics Standards Initiative.

    Science.gov (United States)

    Gibson, Frank; Hoogland, Christine; Martinez-Bartolomé, Salvador; Medina-Aunon, J Alberto; Albar, Juan Pablo; Babnigg, Gyorgy; Wipat, Anil; Hermjakob, Henning; Almeida, Jonas S; Stanislaus, Romesh; Paton, Norman W; Jones, Andrew R

    2010-09-01

    The Human Proteome Organisation's Proteomics Standards Initiative has developed the GelML (gel electrophoresis markup language) data exchange format for representing gel electrophoresis experiments performed in proteomics investigations. The format closely follows the reporting guidelines for gel electrophoresis, which are part of the Minimum Information About a Proteomics Experiment (MIAPE) set of modules. GelML supports the capture of metadata (such as experimental protocols) and data (such as gel images) resulting from gel electrophoresis so that laboratories can be compliant with the MIAPE Gel Electrophoresis guidelines, while allowing such data sets to be exchanged or downloaded from public repositories. The format is sufficiently flexible to capture data from a broad range of experimental processes, and complements other PSI formats for MS data and the results of protein and peptide identifications to capture entire gel-based proteome workflows. GelML has resulted from the open standardisation process of PSI consisting of both public consultation and anonymous review of the specifications.

  6. Gel dosimetry for conformal radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G [Department of Physics of the University and INFN, Milan (Italy)

    2005-07-01

    With the continuum development of conformal radio therapies, aimed at delivering high dose to tumor tissue and low dose to the healthy tissue around, the necessities has appeared of suitable improvement of dosimetry techniques giving the possibility of obtaining dose images to be compared with diagnostic images. Also if wide software has been developed for calculating dose distributions in the fields of various radiotherapy units, experimental verifications are necessary, in particular in the case of complex geometries in conformal radiotherapy. Gel dosimetry is a promising method for imaging the absorbed dose in tissue-equivalent phantoms, with the possibility of 3D reconstruction of the spatial dose distribution, with milli metric resolution. Optical imaging of gel dosimeters, based on visible light absorbance analysis, has shown to be a reliable technique for achieving dose distributions. (Author)

  7. Expanded uncertainty estimation methodology in determining the sandy soils filtration coefficient

    Science.gov (United States)

    Rusanova, A. D.; Malaja, L. D.; Ivanov, R. N.; Gruzin, A. V.; Shalaj, V. V.

    2018-04-01

    The combined standard uncertainty estimation methodology in determining the sandy soils filtration coefficient has been developed. The laboratory researches were carried out which resulted in filtration coefficient determination and combined uncertainty estimation obtaining.

  8. A mucoadhesive in situ gel delivery system for paclitaxel.

    Science.gov (United States)

    Jauhari, Saurabh; Dash, Alekha K

    2006-06-02

    MUC1 gene encodes a transmembrane mucin glycoprotein that is overexpressed in human breast cancer and colon cancer. The objective of this study was to develop an in situ gel delivery system containing paclitaxel (PTX) and mucoadhesives for sustained and targeted delivery of anticancer drugs. The delivery system consisted of chitosan and glyceryl monooleate (GMO) in 0.33M citric acid containing PTX. The in vitro release of PTX from the gel was performed in presence and absence of Tween 80 at drug loads of 0.18%, 0.30%, and 0.54% (wt/wt), in Sorensen's phosphate buffer (pH 7.4) at 37 degrees C. Different mucin-producing cell lines (Calu-3>Caco-2) were selected for PTX transport studies. Transport of PTX from solution and gel delivery system was performed in side by side diffusion chambers from apical to basal (A-B) and basal to apical (B-A) directions. In vitro release studies revealed that within 4 hours, only 7.61% +/- 0.19%, 12.0% +/- 0.98%, 31.7% +/- 0.40% of PTX were released from 0.18%, 0.30%, and 0.54% drug-loaded gel formulation, respectively, in absence of Tween 80. However, in presence of surfactant (0.05% wt/vol) in the dissolution medium, percentages of PTX released were 28.1% +/- 4.35%, 44.2% +/- 6.35%, and 97.1% +/- 1.22%, respectively. Paclitaxel has shown a polarized transport in all the cell monolayers with B-A transport 2 to 4 times higher than in the A-B direction. The highest mucin-producing cell line (Calu-3) has shown the lowest percentage of PTX transport from gels as compared with Caco-2 cells. Transport of PTX from mucoadhesive gels was shown to be influenced by the mucin-producing capability of cell.

  9. Characterization, Washing, Leaching, and Filtration of C-104 Sludge

    Energy Technology Data Exchange (ETDEWEB)

    KP Brooks; PR Bredt; GR Golcar; SA Hartley; LK Jagoda; KG Rappe; MW Urie

    2000-06-09

    Approximately 1,400 g of wet Hanford Tank C-104 Sludge was evaluated by Battelle for the high-level waste (HLW) pretreatment processes of ultrafiltration, dilute caustic washing, and elevated-temperature caustic leaching. The filterability of diluted C-104 sludge was measured with a 0.1-{micro}m sintered metal Mott filter using a 24-inch-long, single-element, crossflow filtration system (cells unit filter [CUF]). While the filtrate was being recirculated prior to washing and leaching, a 6.9 wt% solids slurry was evaluated with a matrix of seven 1-hour conditions of varying trans-membrane pressure (30 to 70 psid) and axial velocity (9 to 15 ft/s). The filtrate flux and backpulse efficiency were determined for each condition. The slurry was concentrated to 23 wt% solids, a second matrix of six 1-hour conditions was performed, and data analogous to that recorded in the first matrix were obtained. The low-solids-concentration matrix produced filtrate flux rates that ranged from 0.038 to 0.083 gpm/ft{sup 2}. The high-solids-concentration matrix produced filtrate flux rates that ranged from 0.0095 to 0.0172 gpm/ft{sup 2}. In both cases, the optimum filtrate flux was at the highest axial velocity (15 ft/s) and transmembrane pressure had little effect. Nearly all of the measured filtrate fluxes were more than an order of magnitude greater than the required plant flux for C-104 of 0.00126 gpm/ft{sup 2}. In both matrices, the filtrate flux appeared to be proportional to axial velocity, and the permeability appeared to be inversely proportional to the trans-membrane pressure. The first test condition was repeated as the last test condition for each matrix. In both cases, there was a significant decrease in filtrate flux, indicating some filter fouling during the test matrix that could not be removed by backpulsing alone, although the backpulse number and duration were not optimized. Following testing of these two matrices, the material was washed within the CUF by

  10. Static and dynamic filtrations of different clay, electrolytes, polymer systems; Filtrations statiques et dynamiques de differents systemes argile, electrolytes, polymere

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y

    1996-04-16

    Filtration properties of model drilling fluids composed of water, clays, electrolytes and water soluble polymers have been studied in static and dynamic conditions on paper filters and rock slices. Filtration experiments combined with cake observations by cryo-S.E.M. and T.E.M., show the influence of the size shape of clay particles as well as their associating mode in suspension, on the texture of the cake, its permeability, and relaxation properties. These parameters depend on the nature of the electrolyte. The polymer reduces the cake permeability by enhancing the dispersion of the clay within the suspension, but mainly by plugging the porous network due its auto aggregation properties. The cake construction in dynamic conditions, is related to the state of aggregation of the initial suspension, its poly-dispersity, its sensitivity to shear rates, and also, to the permeability of the cake built at the beginning of the filtration. In all cases, the rate of thickening of the cake is slower and larger filtrate volumes are obtained compared to the static conditions. Shear rate has two effects: first, to dissociate the weak aggregates in suspension, second, to impose a size selection of the particles in the case of a poly-dispersed suspension. At high shear rates, a cake of constant thin thickness is quickly obtained. The thickness of this limiting cake depends on the fraction of small particles present in suspension, or that can be formed by dissociation of weak aggregates under shear rate. The permeability of this limiting cake formed in dynamic conditions is, as in static conditions, controlled by the size and the shape of the particles that form the cake or by the presence of a build loss reducer water soluble polymer. Filtrations carried out on Fontainebleau sandstones allow to visualize the internal cake and to precise the risks of formation damage by the drilling fluid. (author) 127 refs.

  11. Robust cross-links in molluscan adhesive gels: testing for contributions from hydrophobic and electrostatic interactions.

    Science.gov (United States)

    Smith, A M; Robinson, T M; Salt, M D; Hamilton, K S; Silvia, B E; Blasiak, R

    2009-02-01

    The cross-linking interactions that provide cohesive strength to molluscan adhesive gels were investigated. Metal-based interactions have been shown to play an important role in the glue of the slug Arion subfuscus (Draparnaud), but other types of interactions may also contribute to the glue's strength and their role has not been investigated. This study shows that treatments that normally disrupt hydrophobic or electrostatic interactions have little to no effect on the slug glue. High salt concentrations and non-ionic detergent do not affect the solubility of the proteins in the glue or the ability of the glue proteins to stiffen gels. In contrast, metal chelation markedly disrupts the gel. Experiments with gel filtration chromatography identify a 40 kDa protein that is a central component of the cross-links in the glue. This 40 kDa protein forms robust macromolecular aggregations that are stable even in the presence of high concentrations of salt, non-ionic detergent, urea or metal chelators. Metal chelation during glue secretion, however, may block some of these cross-links. Such robust, non-specific interactions in an aqueous environment are highly unusual for hydrogels and reflect an intriguing cross-linking mechanism.

  12. Applying of isoconversional analysis to calorimetric data on the gel melting

    Science.gov (United States)

    Dranca, I.; Lupascu, T.; Povar, I.

    2012-02-01

    The present study is concerned to the thermal stability of gelatin gels that is defined that their resistance to melting or, in other words, to the thermally stimulated transitions from gel to sol. The both sol-gel and gel-sol transitions were followed by regular Mettler-Toledo DSC 823e and stochastically modulated multi-frequency DSC (TOPEM® by Mettler-Toledo). The DSC data have been treated by using an advanced isoconversional method developed by Vyazovkin [1,2]. The method allows revealing a variation in the effective activation energy (Eα) with the extent of conversion (α). It has been discovered that an increase in the concentration of gelatin solutions causes an increase in the energy barrier to melting of non-isothermally prepared gels.

  13. Numerical Solutions of Mechanical Turbulent Filtration Equation Used in Mechatronics and Micro Mechanic

    OpenAIRE

    Hassan Fathabadi

    2013-01-01

    In this study, several novel numerical solutions are presented to solve the turbulent filtration equation and its special case called “Non-Newtonian mechanical filtration equation”. The turbulent filtration equation in porous media is a very important equation which has many applications to solve the problems appearing especially in mechatronics, micro mechanic and fluid mechanic. Many applied mechanical problems can be solved using this equation. For example, non-Newtonian mechanical filtrat...

  14. Particulate Matter Filtration Design Considerations for Crewed Spacecraft Life Support Systems

    Science.gov (United States)

    Agui, Juan H.; Vijayakumar, R.; Perry, Jay L.

    2016-01-01

    Particulate matter filtration is a key component of crewed spacecraft cabin ventilation and life support system (LSS) architectures. The basic particulate matter filtration functional requirements as they relate to an exploration vehicle LSS architecture are presented. Particulate matter filtration concepts are reviewed and design considerations are discussed. A concept for a particulate matter filtration architecture suitable for exploration missions is presented. The conceptual architecture considers the results from developmental work and incorporates best practice design considerations.

  15. Water equivalence of polymer gel dosimeters

    International Nuclear Information System (INIS)

    Sellakumar, P.; James Jebaseelan Samuel, E.; Supe, Sanjay S.

    2007-01-01

    To evaluate the water equivalence and radiation transport properties of polymer gel dosimeters over the wide range of photon and electron energies 14 different types of polymer gels were considered. Their water equivalence was evaluated in terms of effective atomic number (Z eff ), electron density (ρ e ), photon mass attenuation coefficient (μ/ρ), photon mass energy absorption coefficient (μ en /ρ) and total stopping power (S/ρ) tot of electrons using the XCOM and the ESTAR database. The study showed that the effective atomic number of polymer gels were very close ( en /ρ for all polymer gels were in close agreement ( tot of electrons in polymer gel dosimeters were within 1% agreement with that of water. From the study we conclude that at lower energy (<80keV) the polymer gel dosimeters cannot be considered water equivalent and study has to be carried out before using the polymer gel for clinical application

  16. Public health protection through bank filtration - Kearney Nebraska case study

    Science.gov (United States)

    Esseks, E.; Bellamy, W.; Heinemann, T.; Stocker, K.

    2003-04-01

    The investigation of Kearney's bank filtration system provides further evidence of this technology's capability to assist in providing public health protection, as it relates to drinking water. The results of hydrogeologic and treatment studies demonstrate the capabilities of the Platte River aquifer materials, in this locale, to remove pathogens and their surrogates. Continual monitoring and evaluations will establish the system’s longevity and continued treatment efficacy. The City of Kearney is located in south central Nebraska. The City owns and operates a public water system that serves approximately 24,889 people. The water system includes 12 wells located on Killgore Island in the Platte River. In 1994, the Nebraska Department of Health and Human Services System (Department) determined that 3 wells in the wellfield serving the City of Kearney were ground water under the direct influence of surface water. This determination was based on results of microscopic particulate analysis (MPA). The City of Kearney undertook the natural bank filtration study to determine whether natural bank filtration was occurring at the site and if the filtration was sufficient to meet pathogen treatment requirements designed to protect public health. A preliminary study was undertaken from June through October 1995. This coincided with the City’s peak pumping time, which may be the time when the influence of the River is greatest on the wellfield wells. Hydrogeologic studies assisted in selecting wells that were at highest risk based on shortest travel times and greatest differential head. Data collected included particle counts, MPAs, turbidity, coliform, centrifugate pellet evaluation (CPE) volumes, pH, conductivity, and temperature. Following analysis of data collected during the preliminary 18-week study the Department granted conditional approval of 2-log credit for removal of Giardia lamblia and 1-log credit for removal of viruses through bank filtration, pending the

  17. Facilitating community water supply treatment : from transferring filtration technology to multi-stakeholder learning

    NARCIS (Netherlands)

    Visscher, J.T.

    2006-01-01

    For more than a quarter of a century, IRC has been supporting the development of Slow Sand Filtration (SSF) and more recently, together with CINARA, the pioneering of Multi-Stage Filtration (MSF) - a combination of Gravel Filtration and SSF that has been shown to have great potential as an effective

  18. 77 FR 38857 - Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units of Normal...

    Science.gov (United States)

    2012-06-29

    ... Filtration and Adsorption Units of Normal Atmosphere Cleanup Systems in Light-Water- Cooled Nuclear Power... Criteria for Air Filtration and Adsorption Units of Normal Atmosphere Cleanup Systems in Light-Water-Cooled... draft regulatory guide (DG), DG-1280, ``Design, Inspection, and Testing Criteria for Air Filtration and...

  19. 40 CFR 141.717 - Pre-filtration treatment toolbox components.

    Science.gov (United States)

    2010-07-01

    ... surface water or GWUDI source. (c) Bank filtration. Systems receive Cryptosporidium treatment credit for... paragraph. Systems using bank filtration when they begin source water monitoring under § 141.701(a) must... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Pre-filtration treatment toolbox...

  20. 76 FR 82323 - Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units

    Science.gov (United States)

    2011-12-30

    ... Filtration and Adsorption Units AGENCY: Nuclear Regulatory Commission. ACTION: Draft regulatory guide... for Air Filtration and Adsorption Units of Postaccident Engineered-Safety-Feature Atmosphere Cleanup... testing of air filtration and iodine adsorption units of engineered-safety-feature (ESF) atmosphere...

  1. MATHEMATIC MODEL OF ELECTROMAGNETIC FILTRATION PROCESS OF TECHNOLOGICAL LIQUID AND GAS

    OpenAIRE

    R. A. Мouradova

    2005-01-01

    Electromagnetic filtration as a perspective method of filtration and purification of liquid and gas finds its wide application in oil and chemical industry. However absence of highly-reliable model of calculation that permits unambiguously main operational parameters of electromagnetic filtration and limits its wide application. 

  2. Analysis of filtration properties of locally sourced base oil for the ...

    African Journals Online (AJOL)

    This study examines the use of locally sourced oil like, groundnut oil, melon oil, vegetable oil, soya oil and palm oil as substitute for diesel oil in formulating oil base drilling fluids relative to filtration properties. The filtrate volumes of each of the oils were obtained for filtration control analysis. With increasing potash and ...

  3. Biofouling investigation in membrane filtration systems using Optical Coherence Tomography (OCT)

    KAUST Repository

    Fortunato, Luca

    2017-10-01

    Biofouling represents the main problem in membrane filtration systems. Biofouling arises when the biomass growth negatively impacts the membrane performance parameters (i.e. flux decrease and feed channel pressure drop). Most of the available techniques for characterization of biofouling involve membrane autopsies, providing information ex-situ destructively at the end of the process. OCT, is non-invasive imaging technique, able to acquire scans in-situ and non-destructively. The objective of this study was to evaluate the suitability of OCT as in-situ and non-destructive tool to gain a better understanding of biofouling behavior in membrane filtration systems. The OCT was employed to study the fouling behavior in two different membrane configurations: (i) submerged flat sheet membrane and (ii) spacer filled channel. Through the on-line acquisition of OCT scans and the study of the biomass morphology, it was possible to relate the impact of the fouling on the membrane performance. The on-line monitoring of biofilm formation on a flat sheet membrane was conducted in a gravity-driven submerged membrane bioreactor (SMBR) for 43 d. Four different phases were observed linking the variations in permeate flux with changes in biofilm morphology. Furthermore, the biofilm morphology was used in computational fluid dynamics (CFD) simulation to better understand the role of biofilm structure on the filtration mechanisms. The time-resolved OCT analysis was employed to study the biofouling development at the early stage. Membrane coverage and average biofouling layer thickness were found to be linearly correlated with the permeate flux pattern. An integrated characterization methodology was employed to characterize the fouling on a flat sheet membrane, involving the use of OCT as first step followed by membrane autopsies, revealing the presence of a homogeneous layer on the surface. In a spacer filled channel a 3D OCT time series analysis of biomass development under

  4. Enzymatically crosslinked carboxymethyl-chitosan/gelatin/nano-hydroxyapatite injectable gels for in situ bone tissue engineering application

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Debasish; Bhunia, Bibhas; Banerjee, Indranil [Department of Biotechnology, Indian Institute of Technology Kharagpur (India); Datta, Pallab; Dhara, Santanu [School of Medical Science and Technology, Indian Institute of Technology Kharagpur (India); Maiti, Tapas K., E-mail: maititapask@gmail.com [Department of Biotechnology, Indian Institute of Technology Kharagpur (India)

    2011-10-10

    Present study reports synthesis and characterization of an enzymatically crosslinked injectable gel (iGel) suitable for cell based bone tissue engineering application. The gel comprises of carboxymethyl-chitosan (CMC)/gelatin/nano-hydroxyapatite (nHAp) susceptible to tyrosinase/p-cresol mediated in situ gelling at physiological temperature. Study revealed that a combination of tyrosinase (60U) and p-cresol (2 mM) as crosslinking agents yield rigid gels at physiological temperature when applied to CMC/gelatin within 35 min in presence or absence of nHAp. Rheological study in conjugation with FT-IR analysis showed that an increase in CMC concentration in the gel leads to higher degree of crosslinking and higher strength. Scanning electron microscopy showed that pore sizes of iGels increased with higher gelatin concentration. In vitro study of osteoblast cell proliferation and differentiation showed that, although all iGels are supportive towards the growth of primary osteoblast cells, GC1:1 supported cellular differentiation to the maximum. Application of iGels in mice revealed that stability of the in situ formed gels depends on the degree of crosslinking and CMC concentration. In conclusion, the iGels may be used in treating irregular small bone defects with minimal clinical invasion as well as for bone cell delivery. - Research Highlights: {yields} Enzymatically crosslinked injectable gel made up of CM-chitosan (C)/gelatin (G)/nHAp. {yields} Tyrosinase/p-cresol used for crosslinking and in situ gelling of polymers at 37deg. C. {yields} 60U tyrosinase and 2mM p-cresol is needed for gelation in 35 min. {yields} Higher GC ratio manifests lower crosslinking and gel strength but higher porosity. {yields} GC1:1 shows maximum in vivo gel stability and in vitro osteoblast differentiation.

  5. Characterization of immunogenic Clonorchis sinensis protein fractions by gel fitration chromatography

    Directory of Open Access Journals (Sweden)

    Duan Pham Ngoc

    2015-04-01

    Full Text Available Objective: To characterize immunogenic protein fraction of Clonorchis sinensis (C. sinensis by partial purification. Methods: A total of 30 hamsters were infected with 50 C. sinensis metacercariae, and then C. sinensis protein was purified by gel filtration chromatography. Indirect ELISA and immunoblot were used to detect the antibody in sera of hamsters infected with C. sinensis. Results: The gel filtration showed 2 peaks at high (fraction No. 10 to 14 and low (fraction No. 21 to 26 molecular weight proteins. Indirect ELISA showed that both antibodies of clonorchiasis and opisthorchiasis reacted strongly with early fractions (6 to 14 and the reaction was gradually reduced at middle and late fractions (15 to 50. Both antibodies showed different individual fraction of C. sinensis by immunoblot. It showed several protein bands that the 34 and 37 kDa were major proteins. The 53 kDa protein which was only found in the clonorchiasis reacted with fraction 20. Conclusions: The purified antigen of C. sinensis reacted similarly with both antibodies of clonorchiasis and opisthorchiasis where strong reaction was seen with early fractions. The C. sinensis protein fraction No. 20 may be useful for immunodiagnosis of clonorchiasis.

  6. Filtration, haze and foam characteristics of fermented wort mediated by yeast strain.

    Science.gov (United States)

    Douglas, P; Meneses, F J; Jiranek, V

    2006-01-01

    To investigate the influence of the choice of yeast strain on the haze, shelf life, filterability and foam quality characteristics of fermented products. Twelve strains were used to ferment a chemically defined wort and hopped ale or stout wort. Fermented products were assessed for foam using the Rudin apparatus, and filterability and haze characteristics using the European Brewing Convention methods, to reveal differences in these parameters as a consequence of the choice of yeast strain and growth medium. Under the conditions used, the choice of strain of Saccharomyces cerevisiae effecting the primary fermentation has an impact on all of the parameters investigated, most notably when the fermentation medium is devoid of macromolecular material. The filtration of fermented products has a large cost implication for many brewers and wine makers, and the haze of the resulting filtrate is a key quality criterion. Also of importance to the quality of beer and some wines is the foaming and head retention of these beverages. The foam characteristics, filterability and potential for haze formation in a fermented product have long been known to be dependant on the raw materials used, as well as other production parameters. The choice of Saccharomyces cerevisiae strain used to ferment has itself been shown here to influence these parameters.

  7. Effect of Lactobacillus paracasei Culture Filtrates and Artichoke Polyphenols on Cytokine Production by Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Angelo Sisto

    2016-10-01

    Full Text Available The most recent trend in research on probiotic bacteria aims at the exploitation of bioactive bacterial compounds that are responsible for health-promoting effects and suitable for medical applications. Therefore, the main purpose of this study was to ascertain if the immunomodulatory effects of L. paracasei strains on dendritic cells (DCs were caused by bacterial metabolites released in the culture medium. For that reason, bacterial strains were grown in two media generally used for the culture of DCs, and the effects of culture filtrates on the maturation of DCs and cytokine production were evaluated. Moreover, to reveal potential synergistic effects on the immunomodulation of DCs, an artichoke phenolic extract (APE was added to the media before bacterial growth. The experiments pointed out an interesting anti-inflammatory activity of a culture filtrate obtained after growing a probiotic L. paracasei strain in one of the media supplemented with APE. Therefore, this culture filtrate—which combines the anti-inflammatory activity and the other well-known health-promoting properties of artichoke phenolic compounds—could represent the basis for future particular exploitations.

  8. Effect of polymer type on characterization and filtration performances of multi-walled carbon nanotubes (MWCNT)-COOH-based polymeric mixed matrix membranes.

    Science.gov (United States)

    Sengur-Tasdemir, Reyhan; Mokkapati, Venkata R S S; Koseoglu-Imer, Derya Y; Koyuncu, Ismail

    2018-05-01

    Multi-walled carbon nanotubes (MWCNTs) can be used for the fabrication of mixed matrix polymeric membranes that can enhance filtration perfomances of the membranes by modifying membrane surface properties. In this study, detailed characterization and filtration performances of MWCNTs functionalized with COOH group, blended into polymeric flat-sheet membranes were investigated using different polymer types. Morphological characterization was carried out using atomic force microscopy, scanning electron microscopy and contact angle measurements. For filtration performance tests, protein, dextran, E. coli suspension, Xanthan Gum and real activated sludge solutions were used. Experimental data and analyses revealed that Polyethersulfone (PES) + MWCNT-COOH mixed matrix membranes have superior performance abilities compared to other tested membranes.

  9. Radiation hardening in sol-gel derived Er3+-doped silica glasses

    International Nuclear Information System (INIS)

    Hari Babu, B.; León Pichel, Mónica; Ollier, Nadège; El Hamzaoui, Hicham; Bigot, Laurent; Savelii, Inna; Bouazaoui, Mohamed; Poumellec, Bertrand; Lancry, Matthieu; Ibarra, Angel

    2015-01-01

    The aim of the present paper is to report the effect of radiation on the Er 3+ -doped sol-gel silica glasses. A possible application of these sol-gel glasses could be their use in harsh radiation environments. The sol-gel glasses are fabricated by densification of erbium salt-soaked nanoporous silica xerogels through polymeric sol-gel technique. The radiation-induced attenuation of Er 3+ -doped sol-gel silica is found to increase with erbium content. Electron paramagnetic resonance studies reveal the presence of E′ δ point defects. This happens in the sol-gel aluminum-silica glass after an exposure to γ-rays (kGy) and in sol-gel silica glass after an exposure to electrons (MGy). The concentration levels of these point defects are much lower in γ-ray irradiated sol-gel silica glasses. When the samples are co-doped with Al, the exposure to γ-ray radiation causes a possible reduction of the erbium valence from Er 3+ to Er 2+ ions. This process occurs in association with the formation of aluminum oxygen hole centers and different intrinsic point defects

  10. Tangential filtration technologies membrane and applications for the industry agribusiness

    International Nuclear Information System (INIS)

    Leone, Gian Paolo; Russo, Claudio

    2015-01-01

    The membrane tangential filtration technologies are separation techniques based on the use of semipermeable filters through which, under a pushing force, it is possible to achieve separation of components or suspended in solution as a function of their dimensional characteristics and / or chemical-physical. At the laboratories of the ENEA Research Center Casaccia, as part of the program activities of the Biotechnology and agro-industry division, were studied and developed various filtration processes to membrane in the food industry. The problems have been studied by following a vision sustainable overall, always trying to pair the purification treatment to that of recovery and reuse of water and high value-added components. Ultimate goal of the research conducted is to close the production circuit, ensuring a discharge cycle zero and turning in fact a so-called spread in first, from which to obtain new products. [it

  11. Polymer filtration: A new technology for selective metals recovery

    Energy Technology Data Exchange (ETDEWEB)

    Smith, B.F.; Robison, T.W.; Cournoyer, M.E.; Wilson, K.V.; Sauer, N.N.; Mullen, K.I.; Lu, M.T.; Jarvinen, J.J.

    1995-04-01

    Polymer Filtration (PF) was evaluated for the recovery of electroplating metal ions (zinc and nickel) from rinse waters. Polymer Filtration combines the use of water-soluble metal-binding polymers and ultrafiltration to concentrate metal ions from dilute rinse water solutions. The metal ions are retained by the polymers; the smaller, unbound species freely pass through the ultrafiltration membrane. By using this process the ultrafiltered permeate more than meets EPA discharge limits. The metal ions are recovered from the concentrated polymer solution by pH adjustment using diafiltration and can be recycled to the original electroplating baths with no deleterious effects on the test panels. Metal-ion recovery is accomplished without producing sludge.

  12. Cast Steel Filtration Trials Using Ceramic-Carbon Filters

    Directory of Open Access Journals (Sweden)

    Lipowska B.

    2014-12-01

    Full Text Available Trials of cast steel filtration using two types of newly-developed foam filters in which carbon was the phase binding ceramic particles have been conducted. In one of the filters the source of carbon was flake graphite and coal-tar pitch, while in the other one graphite was replaced by a cheaper carbon precursor. The newly-developed filters are fired at 1000°C, i.e. at a much lower temperature than the currently applied ZrO2-based filters. During filtration trials the filters were subjected to the attack of a flowing metal stream having a temperature of 1650°C for 30 seconds.

  13. Controlling inclusions through filtration in investment casting process

    International Nuclear Information System (INIS)

    Ahmad, R.; Marshall, R.I.

    2004-01-01

    A technique for the placement of a ceramic foam filter in the feeding up of investment mould was developed which proved quite efficient in removing smaller and major inclusions through various filtration modes. Contaminated old aluminum scrap was used to prepare the melt without the addition of any cleansing and covering fluxes and the main reason was to produce more and more inclusions. Vigorous stirring was also intentionally carried out to form as much oxides as possible. During present research work effective filtration was observed. No leakage through sides of the filter occurred and similarly no choking was seen during feeding of molten metal. Microstructural studies showed the maximum retention of inclusions not only on the surface of filters but also within the various channels of the main body of the filter. The microstructures taken from the filtered test pieces were free from inclusions, which showed the effectiveness and proper placement of the filter. (author)

  14. Contaminated fluid filtration plant using pneumatically renewable granulated material

    International Nuclear Information System (INIS)

    Lucas, J.-C.; Messirejean, Pierre.

    1980-01-01

    This invention concerns a plant for the filtration of a contaminated fluid flow using a granulated material capable of absorbing or adsorbing the contaminants. This plant includes a filtration box within which there is at least one appreciably vertical filtering bed filled with the material and crossed by the fluid flow, loading and discharge compartments respectively located at the top and bottom of the box, each in communication with the filtering bed and an air-actuated transfer system for loading and discharging this bed through these compartments. Facilities of this kind are used mainly in the nuclear and chemical engineering industries to rid their waste of radio-iodines, generally constituted by elementary iodine and methyl iodide, or of toxic gases that contaminate them. The granulated material, whose job it is to trap these contaminants by adsorption or absorption, is generally composed of active carbon or zeolites whose utilisation time is limited [fr

  15. Filtration of droplets in the nose of the rabbit

    Energy Technology Data Exchange (ETDEWEB)

    Davies, C N

    1946-01-01

    Optical measurement was done on oil cloud sedimentation before and after passing through nose and out tracheal cannula. The filtering unit which also provides most resistance to flow is maximal turbinates. Nasal cavity is more complex than in man or some other animals, so filtration may be different. Calculation of particle inertia and filter channel width shows that particles > 7 ..mu..m would impact on curves or projections. Particles less than 1.5 ..mu..m should penetrate freely, but low molecular weight gases would be caught by diffusion. The higher the flow, the better the filtration (inertial settling). Broadly summarizing, at ordinary flow rates and nasal resistances, essentially all drops > 7 ..mu..m will be removed. About 50% of 3-..mu.. drops will be removed. < 1.5-..mu..m drops will penetrate.

  16. The use of an air filtration system in podiatry clinics.

    Science.gov (United States)

    McLarnon, Nichola; Burrow, Gordon; Maclaren, William; Aidoo, Kofi; Hepher, Mike

    2003-06-01

    A small-scale study was conducted to ascertain the efficiency and effectiveness of an air filtration system for use in podiatry/chiropody clinics (Electromedia Model 35F (A), Clean Air Ltd, Scotland, UK). Three clinics were identified, enabling comparison of data between podiatry clinics in the West of Scotland. The sampling was conducted using a portable Surface Air Sampler (Cherwell Laboratories, Bicester, UK). Samples were taken on two days at three different times before and after installation of the filtration units. The global results of the study indicate the filter has a statistically significant effect on microbial counts, with an average percentage decrease of 65%. This study is the first time, to the authors' knowledge, such a system has been tested within podiatric practice.

  17. Development of injection moulded, ultrasonically welded immiscible phase filtration devices

    DEFF Research Database (Denmark)

    Kistrup, Kasper

    for ultrasonic welding, suitable for microfluidic systems. A methodology has been established where energy directors can be quickly added to existing mould inserts, using laser micromachining. The produced device was performance tested by isolating methicillin-resistant Staphylococcus aureus from bovine whole....... The device appliesmagnetic bead-based solid-phase extraction for nucleic acid extraction from biological samples, using the immiscible phase filtration (IPF) approach. Device development has employed injection moulding for part fabrication and ultrasonic welding for bonding. Rapid prototyping...

  18. Water Hyacinths and Alligator Weeds for Final Filtration of Sewage

    Science.gov (United States)

    Wolverton, B. C.; Mcdonald, R. C.; Gordon, J.

    1976-01-01

    The potential of water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxerides) (Mart.) Griesb. as secondary and tertiary filtration systems for domestic sewage was demonstrated. These two vascular aquatic plants reduced the suspended solids, total Kjeldahl nitrogen, total phosphorus, BOD sub 5, and total organic carbon levels in domestic sewage from 60 percent to 98 percent within a two week period. These plants grown in domestic sewage were also free of toxic levels of trace heavy metals.

  19. Particle clogging in porous media. Filtration of a smectite solution

    Energy Technology Data Exchange (ETDEWEB)

    Richards, Tobias (Chalmers University of Technology, Goeteborg (Sweden))

    2010-01-15

    The goal of this project is to find out if it is possible for bentonite clay to self heal during leaching with deionized water. The investigation has focused on the formation of a filter cake made of accessory material from MX 80 and the separation of solid material when a smectite solution (1%) is pushed through the cake using a pressure difference of 5 bar. It was also in the scope of this project to design and build the necessary equipment for these experiments. In the literature review it was not found any example that the phenomenon of clogging has been used as a self-healing method previously. It was rather separated also between the clogging of a filter cake (deep bed filtration or cake filtration) and the filtration of colloidal particles. Probably because the latter are in such low concentrations in natural systems and the focus have mainly been in the transport properties of colloids within a filter cake or deep bed filter. An experimental equipment was designed and built. It consists of seven filtration cells that could operate in parallel. All of them are connected to the same source of pressure to ensure equal conditions. A system was also prepared to prevent air from dissolving in the solution because it could create an unwanted expansion in the filter cake due to lower solubility at lower pressure. The experiment showed good separation of smectite particles from the solution when it passed through the filter cake. In all tested cases, the separation was almost complete after long enough time, indicating that the cake has small enough pores to act as a geometrical hinder for the small particles. Comparison between the materials prepared at Chalmers University of Technology and at Clay Technology showed a very good agreement indicating similar properties of the produced smectite

  20. Radioactive slurry waste treatment (1) - flucculant dose effects on filtration

    International Nuclear Information System (INIS)

    Jung, K. H.; Park, S. K.; Jung, W. S.; Baek, S. T.; Jung, K. J.

    1999-01-01

    During the past four decades, the radioactive slurry liquid waste(RSLW) is produced by operation of TRIGA Mark - II and III research reactors, producing radioisotopes and studying on RI utilization. Vacuum filtration of RSLW and flocculated RSLW with cationic, anionic and nonionic flocculants has been investigated. Test results show that critical dose of flocculant is obtained by the estimation of settling rate, cake moisture content and specific cake residence

  1. Cu filtration for dose reduction in neonatal chest imaging

    International Nuclear Information System (INIS)

    Smans, K.; Struelens, L.; Smet, M.; Bosmans, H.; Vanhavere, F.

    2010-01-01

    As neonatal chest images are frequently acquired to investigate the life-threatening lung diseases in prematurely born children, their optimisation in terms of X-ray exposure is required. The aim of this study was to investigate whether such dose-optimisation studies could be performed using a Monte Carlo computer model. More specifically, a Monte Carlo computer model was used to investigate the influence of Cu filtration on image quality and dose in neonatal chest imaging. Monte Carlo simulations were performed with the MCNPX code and used with voxel models representing prematurely born babies (590 and 1910 g). Physical image quality was derived from simulated images in terms of the signal difference-to-noise ratio and signal-to-noise ratio (SNR). To verify the simulation results, measurements were performed using the Gammex 610 Neonatal Chest Phantom, which represents a 1-2 kg neonate. A figure of merit was used to assist in evaluating the optimum balance between the image quality and the patient dose. The results show that the Monte Carlo computer model to investigate dose and image quality works well and can be used in dose-optimisation studies for real clinical practices. Furthermore, working at a specific constant incident air kerma (K a,I ), additional filtration proved to increase SNR with 30%, whereas working at a specific constant detector dose, extra Cu filtration reduces the lung dose with 25%. Optimum balance between patient dose and image quality is found to be 60 kVp (using extra filtration). (authors)

  2. Plasmapheresis and other extracorporeal filtration techniques in critical patients.

    Science.gov (United States)

    Daga Ruiz, D; Fonseca San Miguel, F; González de Molina, F J; Úbeda-Iglesias, A; Navas Pérez, A; Jannone Forés, R

    2017-04-01

    Plasmapheresis is an extracorporeal technique that eliminates macromolecules involved in pathological processes from plasma. A review is made of the technical aspects, main indications in critical care and potential complications of plasmapheresis, as well as of other extracorporeal filtration techniques such as endotoxin-removal columns and other devices designed to eliminate cytokines or modulate the inflammatory immune response in critical patients. Copyright © 2016 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

  3. Novel Particulate Air-Filtration Media: Market Survey

    Science.gov (United States)

    2013-02-01

    larger and more efficient filter designs similar to those being considered for future integrated respirator/helmet systems. To avoid eliminating ...including nonwoven, woven, and electret and combinations of media. Some of the manufacturers identified themselves as specializing in biofiltration or...Three Millipore products were identified. The 0.2 µm hydrophobic Aervent PTFE membrane62 is used for the sterile filtration of gases . Aerex

  4. Hazard categorization of K Basin water filtration upgrade project

    International Nuclear Information System (INIS)

    Conn, K.R.

    1995-01-01

    This supporting document provides the hazards categorization for the K Basin Water Filtration Upgrade Project at K East. All activities associated with the project are less than Hazard Category 3, except for the handling of the ECO-ROK liners containing spent filter cartridges. All activities involving the handling of liners, containing spent cartridges, by monorail, forklift or mobile crane are classified as Hazard Category 3

  5. Particle clogging in porous media. Filtration of a smectite solution

    International Nuclear Information System (INIS)

    Richards, Tobias

    2010-01-01

    The goal of this project is to find out if it is possible for bentonite clay to self heal during leaching with deionized water. The investigation has focused on the formation of a filter cake made of accessory material from MX 80 and the separation of solid material when a smectite solution (1%) is pushed through the cake using a pressure difference of 5 bar. It was also in the scope of this project to design and build the necessary equipment for these experiments. In the literature review it was not found any example that the phenomenon of clogging has been used as a self-healing method previously. It was rather separated also between the clogging of a filter cake (deep bed filtration or cake filtration) and the filtration of colloidal particles. Probably because the latter are in such low concentrations in natural systems and the focus have mainly been in the transport properties of colloids within a filter cake or deep bed filter. An experimental equipment was designed and built. It consists of seven filtration cells that could operate in parallel. All of them are connected to the same source of pressure to ensure equal conditions. A system was also prepared to prevent air from dissolving in the solution because it could create an unwanted expansion in the filter cake due to lower solubility at lower pressure. The experiment showed good separation of smectite particles from the solution when it passed through the filter cake. In all tested cases, the separation was almost complete after long enough time, indicating that the cake has small enough pores to act as a geometrical hinder for the small particles. Comparison between the materials prepared at Chalmers University of Technology and at Clay Technology showed a very good agreement indicating similar properties of the produced smectite

  6. Groundwater Quality Improvement by Using Aeration and Filtration Methods

    OpenAIRE

    Nik N. Nik Daud; Nur H. Izehar; B. Yusuf; Thamer A. Mohamed; A. Ahsan

    2013-01-01

    An experiment was conducted using two aeration methods (water-into-air and air-into-water) and followed by filtration processes using manganese greensand material. The properties of groundwater such as pH, dissolved oxygen, turbidity and heavy metal concentration (iron and manganese) will be assessed. The objectives of this study are i) to determine the effective aeration method and ii) to assess the effectiveness of manganese greensand as filter media in removing iron an...

  7. Modeling Manganese Sorption and Surface Oxidation During Filtration

    OpenAIRE

    Bierlein, Kevin Andrew

    2012-01-01

    Soluble manganese (Mn) is a common contaminant in drinking water sources. High levels of Mn can lead to aesthetic water quality problems, necessitating removal of Mn during treatment to minimize consumer complaints. Mn may be removed during granular media filtration by the â natural greensand effect,â in which soluble Mn adsorbs to manganese oxide-coated (MnOx(s)) media and is then oxidized by chlorine, forming more manganese oxide. This research builds on a previous model developed by Mer...

  8. Dosimetric characteristics of PASSAG as a new polymer gel dosimeter with negligible toxicity

    Science.gov (United States)

    Farhood, Bagher; Abtahi, Seyed Mohammad Mahdi; Geraily, Ghazale; Ghorbani, Mehdi; Mahdavi, Seied Rabi; Zahmatkesh, Mohammad Hasan

    2018-06-01

    Despite many advantages of polymer gel dosimeters, their clinical use is only not realized now. Toxicity of polymer gel dosimeters can be considered as one of their main limitations for use in routine clinical applications. In the current study, a new polymer gel dosimeter is introduced with negligible toxicity. For this purpose, 2-Acrylamido-2-Methy-1-PropaneSulfonic acid (AMPS) sodium salt monomer was replaced instead of acrylamide monomer used in PAGAT gel dosimeter by using %6 T and %50 C to the gel formula and the new formulation is called PASSAG (Poly AMPS Sodium Salt and Gelatin) polymer gel dosimeter. The irradiation of gel dosimeters was carried out using a Co-60 therapy machine. MRI technique was used to quantify the dose responses of the PASSAG gel dosimeter. Then, the MRI responses (R2) of the gel dosimeter was analyzed at different dose values, post-irradiation times, and scanning temperatures. The results showed that the new gel formulation has a negligible toxicity and it is also eco-friendly. In addition, carcinogenicity and genetic toxicity tests are negative for the monomer used in PASSAG. The radiological properties of PASSAG gel dosimeter showed that this substance can be considered as a soft tissue/water equivalent material. Furthermore, dosimetric evaluation of the new polymer gel dosimeter revealed an excellent linear R2-dose response in the evaluated dose range (0-15 Gy). The R2-dose sensitivity and dose resolution of PASSAG gel dosimeter were 0.081 s-1Gy-1 (in 0-15 Gy dose range) and 1 Gy (in 0-10 Gy dose range), respectively. Moreover, it was shown that the R2-dose sensitivity and dose resolution of the new gel dosimeter improves over time after irradiation. It was also found that the R2 response of the PASSAG gel dosimeter has less dependency to the 18, 20, and 24 °C scanning temperature in comparison to that of room temperature (22 °C).

  9. Are vacuum-filtrated reduced graphene oxide membranes symmetric?

    KAUST Repository

    Tang, Bo

    2015-12-02

    Graphene or reduced graphene oxide (rGO) membrane-based materials are promising for many advanced applications due to their exceptional properties. One of the most widely used synthesis methods for rGO membranes is vacuum filtration of graphene oxide (GO) on a filter membrane, followed by reduction, which shows great advantages such as operational convenience and good controllability. Despite vacuum-filtrated rGO membranes being widely used in many applications, a fundamental question is overlooked: are the top and bottom surfaces of the membranes formed at the interfaces with air and with the filter membrane respectively symmetric or asymmetric? This work, for the first time, reports the asymmetry of the vacuum-filtrated rGO membranes and discloses the filter membranes’ physical imprint on the bottom surface of the rGO membrane, which takes place when the filter membrane surface pores have similar dimension to GO sheets. This result points out that the asymmetric surface properties should be cautiously taken into consideration while designing the surface-related applications for GO and rGO membranes.

  10. Centrifugal Filtration System for Severe Accident Source Term Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shu Chang; Yim, Man Sung [KAIST, Daejeon (Korea, Republic of)

    2016-05-15

    The objective of this paper is to present the conceptual design of a filtration system that can be used to process airborne severe accident source term. Reactor containment may lose its structural integrity due to over-pressurization during a severe accident. This can lead to uncontrolled radioactive releases to the environment. For preventing the dispersion of these uncontrolled radioactive releases to the environment, several ways to capture or mitigate these radioactive source term releases are under investigation at KAIST. Such technologies are based on concepts like a vortex-like air curtain, a chemical spray, and a suction arm. Treatment of the radioactive material captured by these systems would be required, before releasing to environment. For current filtration systems in the nuclear industry, IAEA lists sand, multi-venturi scrubber, high efficiency particulate arresting (HEPA), charcoal and combinations of the above in NS-G-1-10, 4.143. Most if not all of the requirements of the scenario for applying this technology near the containment of an NPP site and the environmental constraints were analyzed for use in the design of the centrifuge filtration system.

  11. Are vacuum-filtrated reduced graphene oxide membranes symmetric?

    KAUST Repository

    Tang, Bo; Zhang, Lianbin; Li, Renyuan; Wu, Jinbo; Hedhili, Mohamed Neijib; Wang, Peng

    2015-01-01

    Graphene or reduced graphene oxide (rGO) membrane-based materials are promising for many advanced applications due to their exceptional properties. One of the most widely used synthesis methods for rGO membranes is vacuum filtration of graphene oxide (GO) on a filter membrane, followed by reduction, which shows great advantages such as operational convenience and good controllability. Despite vacuum-filtrated rGO membranes being widely used in many applications, a fundamental question is overlooked: are the top and bottom surfaces of the membranes formed at the interfaces with air and with the filter membrane respectively symmetric or asymmetric? This work, for the first time, reports the asymmetry of the vacuum-filtrated rGO membranes and discloses the filter membranes’ physical imprint on the bottom surface of the rGO membrane, which takes place when the filter membrane surface pores have similar dimension to GO sheets. This result points out that the asymmetric surface properties should be cautiously taken into consideration while designing the surface-related applications for GO and rGO membranes.

  12. Experience with high-temperature filtration of incinerator flue gases

    International Nuclear Information System (INIS)

    Carpentier, S.; de Tassigny, C.

    1990-01-01

    It is always preferable to filter incinerator flue gases as close as possible to their origin, i.e. in a high-temperature zone, and means must be provided to destroy the other organic parts of the flyash resulting from these gases by in-filter combustion. The filter also traps a mineral part of the flyash, which eventually causes clogging and requires replacement or regeneration. Such filtration systems are available and can be operated on an industrial scale. They include candles made of micro-expanded refractory alloys supporting filtering media, porous ceramic candles and other devices. Research and subsequent pilot facility testing have enabled development of alumina fiber filter cartridges that offer more advantages than other equipment employed to date. Specifically, these advantages are: ultralight weight, which enables construction of systems that are relatively unaffected by creep and high-temperature deformations; excellent refractory qualities, which permit a use above 1000 degrees C; insensitivity to thermal shocks and in-situ carbon fines combustion capability; anti-acid quality of the material, which enables high-temperature filtration of acidic flue gases (chlorine and hydrochloric acid, SO x , etc.); low initial pressure drop of the cartridges; dimensional stability of the cartridges, which can be machined to a given tolerance with specific contours after casting and drying. This paper reports the results obtained during the last filtration system test campaign. Details are given for operating conditions, grain sizes and real-time monitoring of various parameters

  13. Improvement of municipal wastewater pretreatment by direct membrane filtration.

    Science.gov (United States)

    Nascimento, Thiago A; Mejía, Fanny R; Fdz-Polanco, Fernando; Peña Miranda, Mar

    2017-10-01

    The high content of particulate matter in municipal wastewater hinders the conventional anaerobic treatments at psychrophilic temperatures. The hydrolysis of the particulate chemical oxygen demand (pCOD) could be the limiting step under these conditions. Therefore, new pretreatments or improved conventional pretreatments are needed in order to separate pCOD. In this work, direct membrane filtration of municipal wastewater, using an ultrafiltration membrane, was investigated. This intensive pretreatment, which aims to separate soluble chemical oxygen demand (sCOD) and to concentrate pCOD, together with anaerobic treatments of both streams at psychrophilic and mesophilic conditions respectively, could be an alternative to the conventional activated sludge process. The obtained results show a removal yield of 24.9% of the total solids (TS) and 45% of total chemical oxygen demand (tCOD), obtaining a permeate free of suspended solids. This physical removal implies the accumulation of solids inside the membrane tank, reaching the values of 45.4 and 4.4 g/L of TS in the sedimentation and filtration sections, respectively. The membrane operated with filtration, backwashing cycles and continuous gas sparging, with a permeate flux predominantly around 10 L/(m 2  h). The results show the viability of the technology to concentrate pCOD and so to improve energy recovery from municipal wastewater.

  14. Active osmotic exchanger for advanced filtration at the nano scale

    Science.gov (United States)

    Marbach, Sophie; Bocquet, Lyderic

    2015-11-01

    One of the main functions of the kidney is to remove the waste products of an organism, mostly by excreting concentrated urea while reabsorbing water and other molecules. The human kidney is capable of recycling about 200 liters of water per day, at the relatively low cost of 0.5 kJ/L (standard dialysis requiring at least 150 kJ/L). Kidneys are constituted of millions of parallel filtration networks called nephrons. The nephrons of all mammalian kidneys present a specific loop geometry, the Loop of Henle, that is believed to play a key role in the urinary concentrating mechanism. One limb of the loop is permeable to water and the other contains sodium pumps that exchange with a common interstitium. In this work, we take inspiration from this osmotic exchanger design to propose new nanofiltration principles. We first establish simple analytical results to derive general operating principles, based on coupled water permeable pores and osmotic pumps. The best filtration geometry, in terms of power required for a given water recycling ratio, is comparable in many ways to the mammalian nephron. It is not only more efficient than traditional reverse osmosis systems, but can also work at much smaller pressures (of the order of the blood pressure, 0.13 bar, as compared to more than 30 bars for pressure-retarded osmosis systems). We anticipate that our proof of principle will be a starting point for the development of new filtration systems relying on the active osmotic exchanger principle.

  15. Evaluation of multistage filtration to reduce sand filter exhaust activity

    International Nuclear Information System (INIS)

    Zippler, D.B.

    1975-01-01

    Air from the Savannah River Plant Fuel Reprocessing facilities is filtered through deep bed sand filters consisting of 8 1 / 2 feet of gravel and sand. These filters have performed satisfactorily for the past 18 years in maintaining radioactive release levels to a minimum. The apparent filter efficiency has been determined for many years by measurements of the quantity of radioactivity in the air stream before and after the filter. Such tests have indicated efficiencies of 99.9 percent or better. Even with sand filter efficiency approaching a single stage HEPA filter, new emphasis on further reduction in release of plutonium activity to the environment prompted a study to determine what value backup HEPA filtration could provide. To evaluate the specific effect additional HEPA filtration would have on the removal of Pu from the existing sand filter exhaust stream, a test was conducted by passing a sidestream of sand-filtered air through a standard 24 x 24 x 11 1 / 2 in. HEPA filter. Isokinetic air samples were withdrawn upstream and downstream of the HEPA filter and counted for alpha activity. Efficiency calculations indicated that backup HEPA filtration could be expected to provide an additional 99 percent removal of the Pu activity from the present sand-filter exhaust. (U.S.)

  16. Organic iodide capture using a zeolite dry filtration

    International Nuclear Information System (INIS)

    Park, Sanggil; Sung, Joonyoung; Kim, Gi-ppeum; Lee, Jaeyoung

    2017-01-01

    An organic iodide, especially, methyl iodide (CH 3 I) would generated non-negligibly from a severe accident in a nuclear power plant. This CH 3 I will be dangerous for human when it was inhaled, it is highly toxic and causes a serious nerve disorder. Even it is a major contributor to a thyroid cancer. In order to prevent its environmental release, it is required to decontaminate using a filtration system. For the removal of CH 3 I from the release gases, wet-type is not ideal due to a high re-volatile characteristics of CH 3 I. It may become volatile after dissolving in a pool and forms CH 3 I again at the surface of water pool. Therefore, a dry-filtration should be installed to remove the CH 3 I. In this study, we preliminary investigate the characteristics of zeolite filtration methods for the removal of CH 3 I. We used both silver ion exchanged ZSM-5-zeolite (Ag+-ZSM-5) to study the effect of silver ion for the removal of iodine from CH 3 I. In summary, the CH 3 I capture tests using a silver ion exchanged zeolite was conducted in the coupled TGAGC test set-up. The mass change of the sample and concentration of CH 3 I were measured. The samples were investigated by the SEM/EDS to see its surface characteristics.

  17. Non-filtration method of processing uranium ores

    International Nuclear Information System (INIS)

    Laskorin, B.N.; Vodolazov, L.I.; Tokarev, N.N.; Vyalkov, V.I.; Goldobina, V.A.; Gosudarstvennyj Komitet po Ispol'zovaniyu Atomnoj Ehnergii SSSR, Moscow)

    1977-01-01

    The development of the non-filtration sorption method has lead to procedures of the sorption leaching and the extraction desorption, which have made it possible to intensify the processing of uranium ores and to improve greatly the technical and economic indexes by eliminating the complex method of multiple filtration and re-pulping of cakes. This method makes it possible to involve more poor uranium raw materials, at the same time extracting valuable components such as molybdenum, vanadium, copper, etc. Considerable industrial experience has been acquired in the sorption of dense pulp with a solid-to-liquid phase ratio of 1:1. This has led to a plant production increase of 1.5-3.0 times, an increase of uranium extraction by 5-10%, a two- to- three-fold increase of labour capacity of the main workers, and to a several-fold decrease of reagents, auxiliary materials, electric energy and vapour. This non-filtration method is a continuous process in all its phases thanks to the use of high-yield and high-power equipment for high-density pulps. (author)

  18. Field Demonstration of Fuel Crud Filtration System at Ulchin Plant

    International Nuclear Information System (INIS)

    Kang, Duk-Won; Lee, Doo-Ho; Park, Jong-Youl; Choi, In-Kyu

    2007-01-01

    Crud deposited onto the fuel assemblies in nuclear power plants was not a serious problem until an upper core flux depression named Axial Offset Anomaly (AOA) was found at Callaway, USA in 1989. Though the mechanism of an AOA is not completely understood, crud is believed to be a key component of initiating AOA. After the sufficient amount of corrosion products in the reactor cooling system are deposited on the fuel clad by a sub-cooled nucleate boiling, boron is adsorbed in the crud. Thus a measurable reduction in the neutron flux occurs which causes an AOA problem. A filtration system has been developed to remove the fuel crud from irradiated fuel assemblies for mitigating the axial offset anomaly under a technical cooperation agreement with DEI (Dominion Engineering Inc.). This filtration system with a fuel cleaning fixture was successfully demonstrated at Ulchin plant unit 2. Within several minutes, detachable crud deposits were effectively removed from the clad surfaces of the fuel assembly. Also, to characterize the crud particles for each fuel assembly, a small crud sampling device and radiation monitor devices were connected to the filtration system during the cleaning operation. In this study, we completed a functional test and demonstration of an ultrasonic fuel cleaning system by using four spent fuel assemblies. It took only 5 minutes to remove the fuel crud from each fuel assembly. In addition, collective dose rates indicated an average of 8 R/Hr per assembly

  19. Ultra-filtration measurement using CT imaging technology

    International Nuclear Information System (INIS)

    Lu Junfeng; Lu Wenqiang

    2009-01-01

    As a functional unit in the hemodialysis process, dialyzer captured quite a few medical research interests since 1980s. In the design of dialyzer or in the ongoing hemodialysis process, to estimate the ultra-filtration amount of a dialyzer, the sideway loss of the running blood flow through hollow fibers or filtration channels should be measured. This further leads to the measurement of the blood flow inside the dialyzer. For this measurement, a non-invasive method is highly desired because of the high-dense bundled hollow fibers or packed channels inside the dialyzer. As non-invasive measurement tools, CT (Computed Tomography) technologies were widely used for tissue, bone, and cancerous clinical analyses etc .... Thus, in this paper, a CT system is adopted to predict the blood flow inside a hollow fiber dialyzer. In view of symmetric property of the hollow fiber dialyzer, the largest cutting plane that parallels to the cylindrical dialyzer was analyzed by the CT system dynamically. And then, a noninvasive image analysis method used to predict the ultra-filtration amount is proposed.

  20. Simple method for the estimation of glomerular filtration rate

    Energy Technology Data Exchange (ETDEWEB)

    Groth, T [Group for Biomedical Informatics, Uppsala Univ. Data Center, Uppsala (Sweden); Tengstroem, B [District General Hospital, Skoevde (Sweden)

    1977-02-01

    A simple method is presented for indirect estimation of the glomerular filtration rate from two venous blood samples, drawn after a single injection of a small dose of (/sup 125/I)sodium iothalamate (10 ..mu..Ci). The method does not require exact dosage, as the first sample, taken after a few minutes (t=5 min) after injection, is used to normilize the value of the second sample, which should be taken in between 2 to 4 h after injection. The glomerular filtration rate, as measured by standard insulin clearance, may then be predicted from the logarithm of the normalized value and linear regression formulas with a standard error of estimate of the order of 1 to 2 ml/min/1.73 m/sup 2/. The slope-intercept method for direct estimation of glomerular filtration rate is also evaluated and found to significantly underestimate standard insulin clearance. The normalized 'single-point' method is concluded to be superior to the slope-intercept method and more sophisticated methods using curve fitting technique, with regard to predictive force and clinical applicability.

  1. Modeling the filtration ability of stockpiled filtering facepiece

    Science.gov (United States)

    Rottach, Dana R.

    2016-03-01

    Filtering facepiece respirators (FFR) are often stockpiled for use during public health emergencies such as an infectious disease outbreak or pandemic. While many stockpile administrators are aware of shelf life limitations, environmental conditions can lead to premature degradation. Filtration performance of a set of FFR retrieved from a storage room with failed environmental controls was measured. Though within the expected shelf life, the filtration ability of several respirators was degraded, allowing twice the penetration of fresh samples. The traditional picture of small particle capture by fibrous filter media qualitatively separates the effect of inertial impaction, interception from the streamline, diffusion, settling, and electrostatic attraction. Most of these mechanisms depend upon stable conformational properties. However, common FFR rely on electrets to achieve their high performance, and over time heat and humidity can cause the electrostatic media to degrade. An extension of the Langevin model with correlations to classical filtration concepts will be presented. The new computational model will be used to predict the change in filter effectiveness as the filter media changes with time.

  2. Electrically tunable coherent optical absorption in graphene with ion gel.

    Science.gov (United States)

    Thareja, Vrinda; Kang, Ju-Hyung; Yuan, Hongtao; Milaninia, Kaveh M; Hwang, Harold Y; Cui, Yi; Kik, Pieter G; Brongersma, Mark L

    2015-03-11

    We demonstrate electrical control over coherent optical absorption in a graphene-based Salisbury screen consisting of a single layer of graphene placed in close proximity to a gold back reflector. The screen was designed to enhance light absorption at a target wavelength of 3.2 μm by using a 600 nm-thick, nonabsorbing silica spacer layer. An ionic gel layer placed on top of the screen was used to electrically gate the charge density in the graphene layer. Spectroscopic reflectance measurements were performed in situ as a function of gate bias. The changes in the reflectance spectra were analyzed using a Fresnel based transfer matrix model in which graphene was treated as an infinitesimally thin sheet with a conductivity given by the Kubo formula. The analysis reveals that a careful choice of the ionic gel layer thickness can lead to optical absorption enhancements of up to 5.5 times for the Salisbury screen compared to a suspended sheet of graphene. In addition to these absorption enhancements, we demonstrate very large electrically induced changes in the optical absorption of graphene of ∼3.3% per volt, the highest attained so far in a device that features an atomically thick active layer. This is attributable in part to the more effective gating achieved with the ion gel over the conventional dielectric back gates and partially by achieving a desirable coherent absorption effect linked to the presence of the thin ion gel that boosts the absorption by 40%.

  3. Swimming micro-robot powered by stimuli-sensitive gel

    Science.gov (United States)

    Masoud, Hassan; Alexeev, Alexander

    2012-11-01

    Using three-dimensional computer simulations, we design a simple maneuverable micro-swimmer that can self-propel and navigate in highly viscous (low Reynolds-number) environments. Our simple swimmer consists of a cubic gel body which periodically changes volume in response to external stimuli, two rigid rectangular flaps attached to the opposite sides of the gel body, and a flexible steering flap at the front end of the swimmer. The stimuli-sensitive body undergoes periodic expansions (swelling) and contractions (deswelling) leading to a time-irreversible beating motion of the propulsive flaps that propel the micro-swimmer. Thus, the responsive gel body acts as an ``engine'' actuating the motion of the swimmer. We examine how the swimming speed depends on the gel and flap properties. We also probe how the swimmer trajectory can be changed using a responsive steering flap whose curvature is controlled by an external stimulus. We show that the turning occurs due to steering flap bending and periodic beating. Furthermore, our simulations reveal that the turning direction can be regulated by changing the intensity of external stimulus.

  4. Metal-silica sol-gel materials

    Science.gov (United States)

    Stiegman, Albert E. (Inventor)

    2002-01-01

    The present invention relates to a single phase metal-silica sol-gel glass formed by the co-condensation of a transition metal with silicon atoms where the metal atoms are uniformly distributed within the sol-gel glass as individual metal centers. Any transition metal may be used in the sol-gel glasses. The present invention also relates to sensor materials where the sensor material is formed using the single phase metal-silica sol-gel glasses. The sensor materials may be in the form of a thin film or may be attached to an optical fiber. The present invention also relates to a method of sensing chemicals using the chemical sensors by monitoring the chromatic change of the metal-silica sol-gel glass when the chemical binds to the sensor. The present invention also relates to oxidation catalysts where a metal-silica sol-gel glass catalyzes the reaction. The present invention also relates to a method of performing oxidation reactions using the metal-silica sol-gel glasses. The present invention also relates to organopolymer metal-silica sol-gel composites where the pores of the metal-silica sol-gel glasses are filled with an organic polymer polymerized by the sol-gel glass.

  5. Electrophoretic analysis of proteins from Mycoplasma hominis strains detected by SDS-PAGE, two-dimensional gel electrophoresis and immunoblotting

    DEFF Research Database (Denmark)

    Andersen, H; Birkelund, Svend; Christiansen, Gunna

    1987-01-01

    The proteins of 14 strains of Mycoplasma hominis were compared by SDS-PAGE in gradient gels, by two-dimensional (2D) gel electrophoresis of extracts of 35S-labelled cells and by immunoblot analysis of cell proteins. The strains examined included the M. hominis type strain PG21 and 13 others...... isolated variously from genital tract, mouth, blood, upper urinary tract and a wound. These 14 strains shared 76-99% of proteins in SDS-gradient gel analysis and 41-72% in the 2D gels. As expected, the immunoblot analysis likewise revealed the existence of an extensive common protein pattern in M. hominis...

  6. Challenges of Membrane Filtration for Produced Water Treatment in Offshore Oil & Gas Production

    DEFF Research Database (Denmark)

    Jepsen, Kasper Lund; Hansen, Leif; Mai, Christian

    2016-01-01

    struggling to their fundamental limit, therefore the membrane filtration technology turns to be a potential candidate for zero pollutant discharge. Membrane filtration technology suffers from the notorious fouling problem, where many methods for fouling prevention and removal are explored, the general idea...... is to guarantee that a relatively high permeability can be kept during filtration. Another crucial issue using membrane filtration technology is its huge energy consumption, for which there is little research has been done so far to systematically investigate and optimize the filtration system’s energy efficiency...

  7. Uptake of wheel-filtration among clients of a supervised injecting facility: Can structured education work?

    Science.gov (United States)

    Steele, Maureen; Silins, Edmund; Flaherty, Ian; Hiley, Sarah; van Breda, Nick; Jauncey, Marianne

    2018-01-01

    Wheel-filtration of pharmaceutical opioid tablets is a recognised harm reduction strategy, but uptake of the practice among people who inject drugs is low. The study aimed to: (i) examine perceptions of filtration practices; (ii) provide structured education on wheel-filtration; and (iii) assess uptake of the practice. Frequent opioid tablet injectors (n = 30) attending a supervised injecting facility in Sydney, Australia, received hands-on instruction on wheel-filtration based on recommended practice. Pre-education, post-education and follow-up questionnaires were administered. Wheel-filtration was generally regarded as better than cotton-filtration (the typical method) in terms of perceived effects on health, ease of use and overall drug effect. Sixty-eight percent of those who said they would try wheel-filtration after the education had actually done so. Of those who usually used cotton-filtration, over half (60%) had used wheel-filtration two weeks later. Uptake of safer preparation methods for pharmaceutical opioid tablets increases after structured education in wheel-filtration. Findings suggest that SIFs are an effective site for this kind of education. Supervised injecting facility workers are uniquely positioned to provide harm reduction education at the time of injection. [Steele M, Silins E, Flaherty I, Hiley S, van Breda N, Jauncey M. Uptake of wheel-filtration among clients of a supervised injecting facility: Can structured education work? Drug Alcohol Rev 2018;37:116-120]. © 2017 Australasian Professional Society on Alcohol and other Drugs.

  8. Preliminary evaluation of fungicidal and termiticidal activities of filtrates from biomass slurry fuel production

    Energy Technology Data Exchange (ETDEWEB)

    Kartal, S.N. [Istanbul University (Turkey). Forestry Faculty; Imamura, Y. [Kyoto University (Japan). Wood Research Institute; Tsuchiya, F.; Ohsato, K. [JGC Corporation, Yokohama (Japan)

    2004-10-01

    Biomass slurry fuel (BSF) production has recently been developed as a natural energy for the conversion of solid biomass into fuel. In addition to using fuel, filtrates from BSF production may also serve a chemical source with several organic compounds. There is an increasing interest in the research and application of biomass-based filtrates. In this study, fungicidal and termiticidal properties of filtrates from BSF production using sugi (Cryptomeria japonica) and acacia (Acacia mangium) wood were evaluated in laboratory decay and termite resistance tests. Wood blocks treated with the filtrates showed increased resistance against brown-rot fungus, Formitopsis palustris. However the filtrates from sugi wood processed at 270{sup o}C which contained less phenolic compounds than the other filtrates were effective against white-rot fungus, Trametes versicolor. Phenolic compounds of filtrates seemed to play a role in the decay resistance tests however the filtrates did not increase the durability of the wood blocks against subterranean termites Coptotermes formosanus. Despite high acetic and lactic acid content of the filtrates, vanillin content of the filtrates may have served as an additional food source and promoted termite attack. It can be concluded that filtrates with phenolic compounds from lignin degradation during BSF production can be considered for targeted inhibition of brown-rot. (author)

  9. Measuring of filtration efficiency of nonwoven textiles in volume from scattered light by seeding particles

    Directory of Open Access Journals (Sweden)

    Sidlof P.

    2013-04-01

    Full Text Available This paper deals with the method which calculates a filtration efficiency of nonwoven textiles from scattered light intensity by seeding particles. Thefiltration efficiency is commonly measured by particle counters. Samples of liquid or gas are taken during a test in front of and behind a filtration material. The concentration of particles is measured and the filtration efficiency is calculated. The filtration efficiency does not have to be uniform in itswhole surface. The uniformity of filtration is another indicator of a quality of filtration materials. Measurements described in this article were performed on a water filtration setup which enables optical access to the place where the filtration material is mounted. Pictures of illuminated seeding particles are made by a laser sheet and a camera. Visualisation of the filtration process enables measuring of the efficiency of separation versus time and also versus two-dimensional position in case of use of a traverse mechanism. The filtration textiles were tested by 1 μm seeding particles. Mean value of light intensity and number of bright pixels in evaluative areas during image analysis were obtained. On the basis of these data, the filtration efficiency iscalculated. The best image analysis method was chosen.

  10. The Structure of the MAP2K MEK6 Reveals an Autoinhibitory Dimer

    Energy Technology Data Exchange (ETDEWEB)

    Min, Xiaoshan; Akella, Radha; He, Haixia; Humphreys, John M.; Tsutakawa, Susan E.; Lee, Seung-Jae; Tainer, John A.; Cobb, Melanie H.; Goldsmith, Elizabeth J.

    2009-07-13

    MAP2Ks are dual-specificity protein kinases functioning at the center of three-tiered MAP kinase modules. The structure of the kinase domain of the MAP2K MEK6 with phosphorylation site mimetic aspartic acid mutations (MEK6/{Delta}N/DD) has been solved at 2.3 {angstrom} resolution. The structure reveals an autoinhibited elongated ellipsoidal dimer. The enzyme adopts an inactive conformation, based upon structural queues, despite the phosphomimetic mutations. Gel filtration and small-angle X-ray scattering analysis confirm that the crystallographically observed ellipsoidal dimer is a feature of MEK6/{Delta}N/DD and full-length unphosphorylated wild-type MEK6 in solution. The interface includes the phosphate binding ribbon of each subunit, part of the activation loop, and a rare 'arginine stack' between symmetry-related arginine residues in the N-terminal lobe. The autoinhibited structure likely confers specificity on active MAP2Ks. The dimer may also serve the function in unphosphorylated MEK6 of preventing activation loop phosphorylation by inappropriate kinases.

  11. Crossflow Filtration: EM-31, WP-2.3.6

    International Nuclear Information System (INIS)

    Duignan, M.; Nash, C.; Poirier, M.

    2011-01-01

    In the interest of accelerating waste treatment processing, the DOE has funded studies to better understand filtration with the goal of improving filter fluxes in existing crossflow equipment. The Savannah River National Laboratory (SRNL) performed some of those studies, with a focus on start-up techniques, filter cake development, the application of filter aids (cake forming solid precoats), and body feeds (flux enhancing polymers). This paper discusses the progress of those filter studies. Crossflow filtration is a key process step in many operating and planned waste treatment facilities to separate undissolved solids from supernate solutions. This separation technology generally has the advantage of self-cleaning through the action of wall shear stress created by the flow of waste slurry through the filter tubes. However, the ability of filter wall self-cleaning depends on the slurry being filtered. Many of the alkaline radioactive wastes are extremely challenging to filtration, e.g., those containing compounds of aluminum and iron, which have particles whose size and morphology reduce permeability. Unfortunately, low filter flux can be a bottleneck in waste processing facilities such as the Savannah River Integrated Salt Disposition Process and the Hanford Waste Treatment Plant. Any improvement to the filtration rate would lead directly to increased throughput of the entire process. To date increased rates are generally realized by either increasing the crossflow filter feed flow rate, limited by pump capacity, or by increasing filter surface area, limited by space and increasing the required pump load. SRNL set up both dead-end and crossflow filter tests to better understand filter performance based on filter media structure, flow conditions, filter cleaning, and several different types of filter aids and body feeds. Using non-radioactive simulated wastes, both chemically and physically similar to the actual radioactive wastes, the authors performed several

  12. CROSSFLOW FILTRATION: EM-31, WP-2.3.6

    Energy Technology Data Exchange (ETDEWEB)

    Duignan, M.; Nash, C.; Poirier, M.

    2011-02-01

    In the interest of accelerating waste treatment processing, the DOE has funded studies to better understand filtration with the goal of improving filter fluxes in existing crossflow equipment. The Savannah River National Laboratory (SRNL) performed some of those studies, with a focus on start-up techniques, filter cake development, the application of filter aids (cake forming solid precoats), and body feeds (flux enhancing polymers). This paper discusses the progress of those filter studies. Crossflow filtration is a key process step in many operating and planned waste treatment facilities to separate undissolved solids from supernate solutions. This separation technology generally has the advantage of self-cleaning through the action of wall shear stress created by the flow of waste slurry through the filter tubes. However, the ability of filter wall self-cleaning depends on the slurry being filtered. Many of the alkaline radioactive wastes are extremely challenging to filtration, e.g., those containing compounds of aluminum and iron, which have particles whose size and morphology reduce permeability. Unfortunately, low filter flux can be a bottleneck in waste processing facilities such as the Savannah River Integrated Salt Disposition Process and the Hanford Waste Treatment Plant. Any improvement to the filtration rate would lead directly to increased throughput of the entire process. To date increased rates are generally realized by either increasing the crossflow filter feed flow rate, limited by pump capacity, or by increasing filter surface area, limited by space and increasing the required pump load. SRNL set up both dead-end and crossflow filter tests to better understand filter performance based on filter media structure, flow conditions, filter cleaning, and several different types of filter aids and body feeds. Using non-radioactive simulated wastes, both chemically and physically similar to the actual radioactive wastes, the authors performed several

  13. Research on pre-staining gel electrophoresis

    International Nuclear Information System (INIS)

    Zhong Ruibo; Liu Yushuang; Zhang Ping; Liu Jingran; Zhao Guofen; Zhang Feng

    2014-01-01

    Background: Gel electrophoresis is a powerful biochemical separation technique. Most biological molecules are completely transparent in the visible region of light, so it is necessary to use staining to show the results after gel electrophoresis, and the general steps of conventional staining methods are time-consuming. Purpose: We try to develop a novel approach to simplify the gel electrophoresis: Pre-Staining Gel Electrophoresis (PSGE), which can make the gel electrophoresis results monitored in real time. Methods: Pre-stain the protein samples with Coomassie Brilliant Blue (CBB) for 30 min before loading the sample into the gel well. Results and Conclusion: PSGE can be successfully used to analyze the binding efficiency of Bovine Serum Albumin (BSA) and amphiphilic polymer via chemical coupling and physical absorption, and the double PSGE also shows a great potential in bio-analytical chemistry. (authors)

  14. Functional coatings: the sol-gel approach

    International Nuclear Information System (INIS)

    Belleville, Ph.

    2010-01-01

    CEA's sol-gel laboratory is specialized in the development of innovative sol-gel optical coatings and has extended its application field to membrane materials and coatings for energy conversion, to electric coatings for microelectronics devices and to thin films for gas sensing. This article describes, by way of examples, the laboratory's research on sol-gel functional coatings, including nano-material synthesis, organic-inorganic hybrid-based solution preparation as well as deposition process development and prototyping. (author)

  15. Dosimetry Evolution in Teletherapy: Polimer Gel

    Science.gov (United States)

    Hamann, J. H.; Peixoto, J. G. P.

    2018-03-01

    Polymer gels evolution and chemical composition used in dosimetry. Type Composition First gels Folin’s Phenol or Gallic Acid Polymer Gel Agarose and N,N’-methylene-bis-acrylamide BANANA Bis, acrylamide, nitrous oxide and agarose BANG-1TM Bis, acrylamide, nitrogen and gelatin BANG-2TM Bis, acrylic acid, sodium hydroxide, nitrogen and gelatin BANG-3TM Bis, methacrylate acid, sodium hydroxide, nitrogen and gelatin MAGIC Methacrylate acid, ascorbic acid, gelatin and copper sulphate

  16. Stabilized aqueous gels and uses thereof

    Energy Technology Data Exchange (ETDEWEB)

    Swanson, B.L.

    1978-08-29

    New improved aqueous gels, and methods of using same in contacting subterranean formations, are provided. The gels are prepared by gelling an aqueous brine having incorporated therein a water-soluble cellulose ether such as a carboxymethylcellulose (CMC), and are rendered more stable to decomposition by incorporating a sulfoalkylated tannin stabilizing agent, such as a sulfomethylated quebracho (SMQ), in the gel during the preparation thereof.

  17. Microfluidics of soft granular gels

    Science.gov (United States)

    Nixon, Ryan; Bhattacharjee, Tapomoy; Sawyer, W. Gregory; Angelini, Thomas E.

    Microfluidic methods for encapsulating cells and particles typically involve drop making with two immiscible fluids. The main materials constraint in this approach is surface tension, creating inherent instability between the two fluids. We can eliminate this instability by using miscible inner and outer phases. This is achieved by using granular micro gels which are chemically miscible but physically do not mix. These microgels are yield stress materials, so they flow as solid plugs far from shear gradients, and fluidize where gradients are generated - near an injection nozzle for example. We have found that tuning the yield stress of the material by varying polymer concentration, device performance can be controlled. The solid like behavior of the gel allows us to produces infinitely stable jets that maintain their integrity and configuration over long distances and times. These properties can be combined and manipulated to produce discrete particulate bunches of an inner phase, flowing inside of an outer phase, well enough even to print a Morse code message suspended within flow chambers about a millimeter in diameter moving at millimeters a second.

  18. Role of pluronics on rheological, drying and crack initiation of 'suckable' gels of decontamination; Role des pluronics sur les proprietes rheologiques, de sechage et de fracturation des gels 'aspirables' de decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Bousquet, C

    2007-12-15

    The aim of this work was to understand the role of an addition of pluronics on the rheological behaviour, the drying and the fracturing of 'suckable' gels used for nuclear decontamination. The system studied was an aqueous suspension of silica (100 g/L of Aerosil 380) in a strong acidic medium (HNO{sub 3}/H{sub 3}PO{sub 4} 1.5 mol/L/1.5 mol/L) in presence of pluronics. Pluronics are amphiphilic tri-blocks copolymers composed of ethylene poly-oxide blocks and of propylene poly-oxide. The first part of this study deals with the characterization of the rheological properties of the gels. From viscosity retaking measurements, flow rheo-grams analysis and the viscoelastic properties of the gels, have been determined an improvement of the rheological properties of the gels significant from the addition of 5 g/L of copolymer. In a second part, the determination of adsorption isotherms coupled to small angles neutrons diffusion measurements has revealed that copolymers are adsorbed flat on silica in bridging the aggregates between them and that the improvement of the rheological behaviour of the gels is due to the increase of the bonds density of the gelled lattice. Moreover, beyond 10 g/L, the adsorption saturation of copolymers at the surface of the silica prevents the bridging of the aggregates which induces the gel destabilization. The last part of this work deals with the characterization of characteristic values of drying and of crack initiation of gels. Then is revealed a relation between the drying kinetics and the formation of cracks in the gel layer. Moreover, the study of the evolution of stresses in the gel layer during time allows to reveal that the addition of pluronics to the formulation of gels allows to improve the gel resistance to the crack initiation and to the delamination. (O.M.)

  19. Conducting polymer electrodes for gel electrophoresis.

    Directory of Open Access Journals (Sweden)

    Katarina Bengtsson

    Full Text Available In nearly all cases, electrophoresis in gels is driven via the electrolysis of water at the electrodes, where the process consumes water and produces electrochemical by-products. We have previously demonstrated that π-conjugated polymers such as poly(3,4-ethylenedioxythiophene (PEDOT can be placed between traditional metal electrodes and an electrolyte to mitigate electrolysis in liquid (capillary electroosmosis/electrophoresis systems. In this report, we extend our previous result to gel electrophoresis, and show that electrodes containing PEDOT can be used with a commercial polyacrylamide gel electrophoresis system with minimal impact to the resulting gel image or the ionic transport measured during a separation.

  20. Ionic liquid based multifunctional double network gel

    Science.gov (United States)

    Ahmed, Kumkum; Higashihara, Tomoya; Arafune, Hiroyuki; Kamijo, Toshio; Morinaga, Takashi; Sato, Takaya; Furukawa, Hidemitsu

    2015-04-01

    Gels are a promising class of soft and wet materials with diverse application in tissue engineering and bio-medical purpose. In order to accelerate the development of gels, it is required to synthesize multi-functional gels of high mechanical strength, ultra low surface friction and suitable elastic modulus with a variety of methods and new materials. Among many types of gel ionic gel made from ionic liquids (ILs) could be used for diverse applications in electrochemical devices and in the field of tribology. IL, a promising materials for lubrication, is a salt with a melting point lower than 100 °C. As a lubricant, ILs are characterized by an extremely low vapor pressure, high thermal stability and high ion conductivity. In this work a novel approach of making double network DN ionic gel using IL has been made utilizing photo polymerization process. A hydrophobic monomer Methyl methacrylate (MMA) has been used as a first network and a hydrophobic IL monomer, N,N-diethyl-N-(2-mthacryloylethyl)-N-methylammonium bistrifluoromethylsulfonyl)imide (DEMM-TFSI) has been used as a second network using photo initiator benzophenon and crosslinker triethylene glycol dimethacrylate (TEGDMA). The resulting DN ionic gel shows transparency, flexibility, high thermal stability, good mechanical toughness and low friction coefficient value which can be a potential candidate as a gel slider in different mechanical devices and can open a new area in the field of gel tribology.

  1. Gel nano-particulates against radioactivity

    International Nuclear Information System (INIS)

    Deroin, Ph.

    2004-01-01

    The Argonne research center (USA) has developed a 'super-gel' compound, a polymer close to those used in baby's diapers, which can reach a 90% efficiency in the radioactive decontamination of porous materials, like bricks or concrete. The contaminated materials are sprayed with a mixture of polymer gel and wetting agent with nano-particulates in suspension. Under the action of the wetting agent, radioactivity migrates from the pores to the gel and is trapped by the nano-particulates. The drying and recycling of the gel allows to reduce the volume of radioactive wastes. Short paper. (J.S.)

  2. Conducting polymer electrodes for gel electrophoresis.

    Science.gov (United States)

    Bengtsson, Katarina; Nilsson, Sara; Robinson, Nathaniel D

    2014-01-01

    In nearly all cases, electrophoresis in gels is driven via the electrolysis of water at the electrodes, where the process consumes water and produces electrochemical by-products. We have previously demonstrated that π-conjugated polymers such as poly(3,4-ethylenedioxythiophene) (PEDOT) can be placed between traditional metal electrodes and an electrolyte to mitigate electrolysis in liquid (capillary electroosmosis/electrophoresis) systems. In this report, we extend our previous result to gel electrophoresis, and show that electrodes containing PEDOT can be used with a commercial polyacrylamide gel electrophoresis system with minimal impact to the resulting gel image or the ionic transport measured during a separation.

  3. A nonadhesive solid-gel electrode for a non-invasive brain–machine interface

    Directory of Open Access Journals (Sweden)

    Shigeru eToyama

    2012-07-01

    Full Text Available A non-invasive brain–machine interface (BMI or brain-computer interface (BCI is a technology for helping individuals with disabilities and utilizes neurophysiological signals from the brain to control external machines or computers without requiring surgery. However, when applying EEG methodology, users must place EEG electrodes on the scalp each time, and the development of easy-to-use electrodes for clinical use is required. In this study, we developed a conductive nonadhesive solid-gel electrode for practical non-invasive BMIs. We performed basic material testing, including examining the volume resistivity, viscoelasticity, and moisture-retention properties of the solid gel. Then, we compared the performance of the solid gel, a conventional paste, and an in-house metal pin-based electrode using impedance measurements and P300-BMI testing. The solid gel was observed to be conductive (volume resistivity 13.2 Ωcm and soft (complex modulus 105.4 kPa, and it remained wet for a prolonged period (>10 hours in a dry environment. Impedance measurements revealed that the impedance of the solid-gel-based and conventional paste-based electrodes was superior to that of the pin-based electrode. The EEG measurement suggested that the signals obtained with the solid-gel electrode were comparable to those with the conventional paste-based electrode. Moreover, the P300-BMI study suggested that systems using the solid-gel or pin-based electrodes were effective. One of the advantages of the solid gel is that it does not require cleaning after use, whereas the conventional paste adheres to the hair, which requires washing. Furthermore, the solid-gel electrode was not painful compared with a metal-pin electrode. Taken together, the results suggest that the solid-gel electrode worked well for practical BMIs and could be useful for bedridden patients such as those with amyotrophic lateral sclerosis.

  4. Development of a double-layered ceramic filter for aerosol filtration at high-temperatures: the filter collection efficiency.

    Science.gov (United States)

    de Freitas, Normanda L; Gonçalves, José A S; Innocentini, Murilo D M; Coury, José R

    2006-08-25

    The performance of double-layered ceramic filters for aerosol filtration at high temperatures was evaluated in this work. The filtering structure was composed of two layers: a thin granular membrane deposited on a reticulate ceramic support of high porosity. The goal was to minimize the high pressure drop inherent of granular structures, without decreasing their high collection efficiency for small particles. The reticulate support was developed using the technique of ceramic replication of polyurethane foam substrates of 45 and 75 pores per inch (ppi). The filtering membrane was prepared by depositing a thin layer of granular alumina-clay paste on one face of the support. Filters had their permeability and fractional collection efficiency analyzed for filtration of an airborne suspension of phosphatic rock in temperatures ranging from ambient to 700 degrees C. Results revealed that collection efficiency decreased with gas temperature and was enhanced with filtration time. Also, the support layer influenced the collection efficiency: the 75 ppi support was more effective than the 45 ppi. Particle collection efficiency dropped considerably for particles below 2 microm in diameter. The maximum collection occurred for particle diameters of approximately 3 microm, and decreased again for diameters between 4 and 8 microm. Such trend was successfully represented by the proposed correlation, which is based on the classical mechanisms acting on particle collection. Inertial impaction seems to be the predominant collection mechanism, with particle bouncing/re-entrainment acting as detachment mechanisms.

  5. Effect of operation parameters on the flux stabilization of gravity-driven membrane (GDM) filtration system for decentralized water supply.

    Science.gov (United States)

    Tang, Xiaobin; Ding, An; Qu, Fangshu; Jia, Ruibao; Chang, Haiqing; Cheng, Xiaoxiang; Liu, Bin; Li, Guibai; Liang, Heng

    2016-08-01

    A pilot-scale gravity-driven membrane (GDM) filtration system under low gravitational pressure without any pre-treatment, backwash, flushing, or chemical cleaning was carried out to investigate the effect of operation parameters (including operation pressure, aeration mode, and intermittent filtration) on the effluent quality and permeability development. The results revealed that GDM system exhibited an efficient performance for the removal of suspended substances and organic compounds. The stabilization of flux occurred and the average values of stable flux were 6.6, 8.1, and 8.6 Lm(-2) h(-1) for pressures of 65, 120, and 200 mbar, respectively. In contrast, flux stabilization was not observed under continuous and intermittent aeration conditions. However, aeration (especially continuous aeration) was effective to improve flux and alleviate membrane fouling during 1-month operation. Moreover, intermittent filtration would influence the stabilization of permeate flux, resulting in a higher stable flux (ranging from 6 to 13 Lm(-2) h(-1)). The stable flux significantly improved with the increase of intermittent period. Additionally, GDM systems exhibited an efficient recovery of flux after simple physical cleaning and the analyses of resistance reversibility demonstrated that most of the total resistance was hydraulic reversible resistance (50-75 %). Therefore, it is expected that the results of this study can develop strategies to increase membrane permeability and reduce energy consumption in GDM systems for decentralized water supply.

  6. Comparison effect of azithromycin gel 2% with clindamycin gel 1% in patients with acne

    Directory of Open Access Journals (Sweden)

    Fatemeh Mokhtari

    2016-01-01

    Conclusion: Azithromycin gel has medical impact at least similar to Clindamycin Gel in treatment of mild to moderate acne vulgaris, and it may be consider as suitable drug for resistant acne to conventional topical therapy.

  7. Stacking gels: A method for maximising output for pulsed-field gel electrophoresis

    Directory of Open Access Journals (Sweden)

    Heng See

    2009-01-01

    Full Text Available Pulsed field gel electrophoresis (PFGE, the gold standard of molecular typing methods, has a major disadvantage of an unusually long electrophoretic time. From the original protocol of 6 days, it was modified to 3 days and subsequently to a single day. We describe the procedure of stacking five to six gels one on top of another in order to increase and maximize the output in a shorter time without compromising the resolution and reproducibility. All the variables that affect pulsed field gels during electrophoresis were taken into consideration. We firstly optimized the parameters to be used and secondly determined whether stacking of five to six gels had any effect on the molecular separation during electrophoresis in comparison with a single gel run. DNA preparation, restriction, electrophoresis, staining and gel documentation was carried out based on previously published methods. Gels were analysed using BioNumerics and dice coefficient and unweighted pair group methods were used to generate dendrograms based on 1.5% tolerance values. Identical band profiles and band resolution-separation were seen in the PFGE patterns with single gel and multiple stacking gels. Cluster analysis further strengthened the fact that results from stacking gels were reproducible and comparable with a single gel run. This method of stacking gels saves time and maximizes the output at the same time. The run time for a single gel was about 28 hours, but with six stacked gels the run time was 54 hours compared with 28 x 6 = 168 hours if they were run separately as single gels thus saving time of 67.86%. Beside the big factor of saving time, stacking gels save resources (electricity, reagents, water, chemicals and working time by increasing the sample throughput in a shorter time without compromising on quality of data. But optimization of working parameters is vital depending on the PFGE system used.

  8. Sphingosine-1-Phosphate (S1P)-Related Response of Human Conjunctival Fibroblasts After Filtration Surgery for Glaucoma.

    Science.gov (United States)

    Aoyama-Araki, Yuka; Honjo, Megumi; Uchida, Takatoshi; Yamagishi, Reiko; Kano, Kuniyuki; Aoki, Junken; Aihara, Makoto

    2017-04-01

    To investigate levels of sphingosine-1-phosphate (S1P) in aqueous fluid samples taken before and after filtration surgery and S1P-induced human conjunctival fibroblast (HCF) responses. Levels of S1P and its related sphingophospholipids in aqueous fluid obtained immediately before and after filtration surgery were determined by liquid chromatography-tandem mass spectrometry. HCFs were used for all in vitro experiments. The expression of five S1P receptor subtypes in HCFs was examined by quantitative real-time PCR. The effect of S1P and receptor-specific antagonists on HCF viability and cell migration was assessed by WST-1 assay and scratch migration assay, respectively. Differentiation to myofibroblasts and extracellular matrix production was evaluated by examining changes in F-actin, α-smooth muscle actin (αSMA), and collagen expression with immunocytochemistry, Western blotting, and collagen accumulation assay, respectively. No significant S1P levels in the aqueous fluid samples were detectable immediately before surgery, but postoperative levels of several lysophospholipids, including S1P, dehydro-S1P, and sphingosine, were significantly increased to bioactive concentrations in aqueous fluid in the blebs (P S1P receptor subtypes was detected in HCFs. Although S1P levels did not influence HCF proliferation, S1P enhanced cell migration, which could be inhibited by the S1P2 antagonist JTE 013. F-actin, αSMA, and collagen expression was significantly increased by S1P stimulation and was reduced by JTE 013. Bioactive S1P concentrations were present in the aqueous fluid at the end of filtration surgery. S1P activated HCFs via S1P2 receptors. These results revealed the potential of S1P2 antagonists in preventing scarring after glaucoma filtration surgery.

  9. Hydraulic conductivity changes in river valley sediments caused by river bank filtration - an analysis of specific well capacity

    Science.gov (United States)

    Kaczmarek, Piotr M. J.

    2017-06-01

    Parameters from archive data of the Kalisz-Lis waterworks, located in the Prosna River valley south of Kalisz, have been analysed. Well barrier discharges groundwater from Quaternary sediments which is mixed with riverbank filtration water. The analysis focused on specific well capacity, a parameter that represents the technical and natural aspects of well life. To exclude any aging factor, an examination of specific well capacity acquired only in the first pumping tests of a new well was performed. The results show that wells drilled between 1961 and 2004 have similar values of specific well capacity and prove that > 40 years discharge has had little influence on hydrodynamic conditions of the aquifer, i.e., clogging has either not occurred or is of low intensity. This implies that, in the total water balance of the Kalisz- Lis well barrier, riverbank filtration water made little contribution. In comparison, a similar analysis of archive data on the Mosina-Krajkowo wells of two generations of well barriers located in the Warta flood plains was performed; this has revealed a different trend. There was a significant drop in specific well capacity from the first pumping test of substitute wells. Thus, long-term groundwater discharge in the Warta valley has had a great impact on the reduction of the hydraulic conductivity of sediments and has worsened hydrodynamic conditions due to clogging of river bed and aquifer, which implies a large contribution of riverbank filtration water in the total water well balance. For both well fields conclusions were corroborated by mathematical modeling; in Kalisz-Lis 16.2% of water comes from riverbank filtration, whereas the percentage for Mosina-Krajkowo is 78.9%.

  10. Categorization of rheological scaling models for particle gels applied to casein gels

    NARCIS (Netherlands)

    Mellema, M.; Opheusden, van J.H.J.; Vliet, van T.

    2002-01-01

    Rennet-induced casein gels made from skim milk were studied rheologically. A scaling model or framework for describing the rheological behavior of gels is discussed and used for classification of the structure of casein gels. There are two main parameters in the model that describe the number of

  11. Ophthalmic gels: Past, present and future.

    Science.gov (United States)

    Al-Kinani, Ali A; Zidan, Ghada; Elsaid, Naba; Seyfoddin, Ali; Alani, Adam W G; Alany, Raid G

    2018-02-15

    Aqueous gels formulated using hydrophilic polymers (hydrogels) along with those based on stimuli responsive polymers (in situ gelling or gel forming systems) continue to attract increasing interest for various eye health-related applications. They allow the incorporation of a variety of ophthalmic pharmaceuticals to achieve therapeutic levels of drugs and bioactives at target ocular sites. The integration of sophisticated drug delivery technologies such as nanotechnology-based ones with intelligent and environment responsive systems can extend current treatment duration to provide more clinically relevant time courses (weeks and months instead of hours and days) which will inevitably reduce dose frequency, increase patient compliance and improve clinical outcomes. Novel applications and design of contact lenses and intracanalicular delivery devices along with the move towards integrating gels into various drug delivery devices like intraocular pumps, injections and implants has the potential to reduce comorbidities caused by glaucoma, corneal keratopathy, cataract, diabetic retinopathies and age-related macular degeneration. This review describes ophthalmic gelling systems with emphasis on mechanism of gel formation and application in ophthalmology. It provides a critical appraisal of the techniques and methods used in the characterization of ophthalmic preformed gels and in situ gelling systems along with a thorough insight into the safety and biocompatibility of these systems. Newly developed ophthalmic gels, hydrogels, preformed gels and in situ gelling systems including the latest in the area of stimuli responsive gels, molecularly imprinted gels, nanogels, 3D printed hydrogels; 3D printed devices comprising ophthalmic gels are covered. Finally, new applications of gels in the production of artificial corneas, corneal wound healing and hydrogel contact lenses are described. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Tough ceramic coatings: Carbon nanotube reinforced silica sol-gel

    Science.gov (United States)

    López, A. J.; Rico, A.; Rodríguez, J.; Rams, J.

    2010-08-01

    Silica coatings reinforced with carbon nanotubes were produced via sol-gel route using two mixing techniques of the sol-gel precursors, mechanical and ultrasonic mixing, and dip-coating as deposition process on magnesium alloy substrates. Effective incorporation and distribution of 0.1 wt.% of carbon nanotubes in the amorphous silica matrix of the coatings were achieved using both techniques. Fabrication procedure determines the morphological aspects of the coating. Only mechanical mixing process produced coatings dense and free of defects. Nanoindentation technique was used to examine the influence of the fabrication process in the mechanical features of the final coatings, i.e. indentation fracture toughness, Young's modulus and hardness. A maximum toughening effect of about 24% was achieved in silica coatings reinforced with carbon nanotubes produced by the mechanical mixing route. Scanning electron microscopy investigation revealed that the toughening of these reinforced coatings was mainly due to bridging effect of the reinforcement.

  13. Aluminium - Cobalt-Pillared Clay for Dye Filtration Membrane

    Science.gov (United States)

    Darmawan, A.; Widiarsih

    2018-04-01

    The manufacture of membrane support from cobalt aluminium pillared clay has been conducted. This research was conducted by mixing a clay suspension with pillared solution prepared from the mixture of Co(NO3)2.6H2O and AlCl3.6H2O. The molar ratio between Al and Co was 75:25 and the ratio of [OH-]/[metal] was 2. The clay suspension was stirred for 24 hours at room temperature, filtered and dried. The dried clay was then calcined at 200°C, 300°C and 400°C with a ramp rate of 2°C/min. Aluminium-cobalt-pillared clay was then characterized by XRD and GSA and moulded become a membrane support for subsequent tests on dye filtration. The XRD analysis showed that basal spacing (d 001) value of aluminium cobalt was 19.49 Å, which was higher than the natural clay of 15.08Å however, the basal spacing decreased with increasing calcination temperature. The result of the GSA analysis showed that the pore diameter of the aluminium cobalt pillared clay membrane was almost the same as that of natural clay that were 34.5Å and 34.2Å, respectively. Nevertheless, the pillared clay has a more uniform pore size distribution. The results of methylene blue filtration measurements demonstrated that the membrane filter support could well which shown by a clear filtrate at all concentrations tested. The value of rejection and flux decreased with the increasing concentration of methylene blue. The values of dye rejection and water flux reached 99.89% and 5. 80 x 10-6 kg min-1, respectively but they decreased with increasing concentration of methylene blue. The results of this study indicates that the aluminium-pillared clay cobalt could be used as membrane materials especially for ultrafiltration.

  14. Optical measurements of lung microvascular filtration coefficient using polysulfone fibers.

    Science.gov (United States)

    Klaesner, J W; Roselli, R J; Evans, S; Pou, N A; Parker, R E; Tack, G; Parham, M

    1994-01-01

    Lung fluid balance, which is governed by the product of net transvascular pressure difference and lung filtration coefficient, can be altered in pulmonary diseases. A simple measurement of the lung filtration coefficient (Kfc) would be clinically useful and has been examined by several researchers. Current methods of determining Kfc include gravimetric measurement in isolated lungs and lymph node cannulation, neither of which can be extended to human use. Optical measurements of protein concentration changes in venous blood can be combined with pressure measurements to calculate Kfc. Blood, though, contains red corpuscles, which tend to absorb and scatter light, obscuring these optical measurements. In this study, an optical system was developed in which a polysulfone filter cartridge was used to remove red blood cells before the filtrate was passed through a spectrophotometer. Absorbance changes caused by changes in concentration of albumin labeled with Evans Blue were monitored at 620 nm after venous pressure was elevated by about 13 cm H2O. Optical measurements of Kfc averaged 0.401 +/- 0.074 (ml/min cm H2O 100 g DLW) for an isolated canine lung. Optical measurements of Kfc (0.363 +/- 0.120 ml/min cm H2O 100 g DLW) were made for the first time in an intact, closed chest sheep in which pulmonary pressure was altered by inflating a Foley balloon in the left atrium. We conclude that absorbance and scattering artifacts introduced by red blood cells can be eliminated by first filtering the blood through polysulfone fibers. Kfc measurements using the optical method are similar to values obtained by others using gravimetric methods. Finally, we have demonstrated that the technique can be used to estimate Kfc in an intact animal.

  15. Determination of filtrations and permeability of an earth dam

    International Nuclear Information System (INIS)

    Gomez, H.R.; Baro, G.B.; Gillen, Ricardo.

    1975-11-01

    The aim of this work was to measure with the aid of a radioactive tracer the speed flow of the water filtrating from Sumampa Dam in northeastern Catamarca, while being in operation, and with these data determine if the actual permeability corresponds to the projected one. Iodine-131 was used as tracer and periodical samples were taken from the down stream water in order to determine its activity concentration. In previous perforations ionic interchange resines were used so as to measure simultaneously the fixed Iodine-131. The permeability of the dam was calculated from the obtained speed based on time-concentration curves and applying Darcy formulas for permeability. (author) [es

  16. Radioactive and hazardous wastewater treatment and sludge stabilization by filtration

    International Nuclear Information System (INIS)

    Martin, H.L.; Pickett, J.B.; Langton, C.A.

    1991-01-01

    Concentrated effluents from batch discharges of spent process solutions are mixed with filter cake from treatment of the dilute effluents and stored in a large tank at the optimum high pH for hydroxide precipitation of heavy metals. Supernate is decanted from the storage tanks and mixed with the dilute effluents before treatment. A filtration and stabilization process has been developed to treat and stored sludge as well as the concentrated wastewater slurry as it is generated. A 94% waste volume reduction over conventional technology can be achieved. Furthermore, leachate from the solidified waste filter cake meets the EPA land disposal restrictions

  17. Improved Filtration Technology for Pathogen Reduction in Rural Water Supplies

    Directory of Open Access Journals (Sweden)

    Valentine Tellen

    2010-06-01

    Full Text Available Intermittent bio-sand filtration (BSF is a low-cost process for improving water quality in rural households. This study addresses its two drawbacks: flow limitations requiring excessive waiting, and inadequate purification when high flows are imposed. Two modifications were examined: increasing the sand’s effective size, and adding zero-valent iron (ZVI into the media as a disinfectant. After 65 days, percent reductions in total coliform, fecal coliform, and fecal streptococci averaged 98.9% for traditional BSF and 99% for the improved BSF. Both modifications showed statistically significant improvements. Increased sand size and ZVI addition can counter the drawbacks of traditional BSF.

  18. Indexing Glomerular Filtration Rate to Body Surface Area

    DEFF Research Database (Denmark)

    Redal-Baigorri, Belén; Rasmussen, Knud; Heaf, James Goya

    2014-01-01

    BACKGROUND: Kidney function is mostly expressed in terms of glomerular filtration rate (GFR). A common feature is the expression as ml/min per 1.73 m(2) , which represents the adjustment of the individual kidney function to a standard body surface area (BSA) to allow comparison between individuals....... We investigated the impact of indexing GFR to BSA in cancer patients, as this BSA indexation might affect the reported individual kidney function. METHODS: Cross-sectional study of 895 adults who had their kidney function measured with (51) chrome ethylene diamine tetraacetic acid. Mean values of BSA...

  19. Filtration in ultrasonic field; Filtracao em campo ultrassonico

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Inaura Carolina C. da; Cortes, Marcela de Araujo H.; Marques, Jose Jailton [Universidade Federal de Sergipe (UFS), Aracaju, SE (Brazil). Dept. de Engenharia Quimica

    2008-07-01

    The production of water associated to the petroleum is an issue of big relevance in exploration areas classified as 'exhausted fields'. The current alternative in practice is the re-injection of the wastewater into the geological formation with the dual purpose of increasing oil recovery and pollution minimization. However, produced water presents several components that make impossible its direct re-injection, requiring a previous treatment. In this context, this work presents the state-of-art of filtration in ultrasonic field, in order to contribute to the development of a new treatment technology applicable to the produced water problem. (author)

  20. The Potentiometric Titration of Filtrates from the Bachmann Process

    Science.gov (United States)

    1942-06-23

    SCIENTIFIC RESEARCH AND DEVELOP11ENT The Potentiometric Titration of Filtrates from the Bachmann Process (OD-12) by F. C. Whitmore OSRD No. 654... Potentiometric Titration of Synthetic Mixtures. A? Nitric Acid-Acetic Acid. A sample of 60 ml. glacial acetic acid war diluted to 200 ml. with distilled...i4flinflr?fj3 TADLE 1 CO) |S?lDBnTl» POTENTIOMETRIC TITRATION OF SYNTHETIC t’.IXTURES WITH CONCENTRATED AJKDNIUM HYDROXIDE A; unonium HNO-j- AcOfi Ky

  1. Optimising and Predicting Performance of Industrial Filtrations using Process Data

    DEFF Research Database (Denmark)

    David Bähner, Franz; Santacoloma, Paloma A.; Abildskov, Jens

    2017-01-01

    Industrial cake filtration is non-trivial from an operational point of view. Discrete events such as the removal of filter cake occur on a frequent but irregular basis. These events tend to upset the steady state of the incorporating line, which may constrain plantwide optimisation. A case study...... has been carried out with an industrial partner where changes in the biological feedstock act as strong disturbances on a series of manually reinitialised dead-end pressure leaf filters. This renders production planning a challenging task which,so far, is carried out by experienced operators. We look...

  2. Transport of micropollutants in a riverbank filtration system

    Science.gov (United States)

    van Driezum, Inge; Oudega, Thomas; Reiner, Philipp; Zessner, Matthias; Farnleitner, Andreas; Blaschke, Paul

    2014-05-01

    Groundwater locations at alluvial backwaters are essential for public water supply. Riverbank filtration (RBF) systems are widely used as a means of obtaining public water supplies. Riverbank filtration is an effective way to remove micropollutants from the receiving surface water. The efficiency of the RBF system strongly depends on the residence time of the water in the aquifer and on the soil properties (Ray, 2011). In order to understand all bio- and geochemical processes within the hyporheic zone (e.g. the region were mixing of surface water and groundwater occurs), exchange rates and flow patterns need to be quantified. The main study area covers the porous groundwater aquifer study site (PGWA) - an urban floodplain extending on the left bank of the River Danube downstream of the City of Vienna. It is one of the main groundwater bodies in Austria. Groundwater quality in the PGWA is influenced by a combination of anthropogenic activities, industry, wastewater treatment plants, heavy precipitation events and floodings. The upper layer of the DPA is impermeable, preventing pollution originating from the surface. The upper layer consists of silt. The underlying confined aquifer consists of sand and gravel layers. Hydraulic conductivities range from 5 x 10-2 m/s up to 5 x 10-5 m/s. Underneath the aquifer are alternating sand an clay/silt layers. Samples are taken from two transects in the DPA. These transects consist of four piezometers in the first few meters of the groundwater aquifer. Several other piezometers are placed downstream from the river-groundwater interface. The behaviour of the micropollutants in the hyporheic zone can therefore be studied intensively. The transport behaviour of several micropollutants is modeled using carbamazepine (CBZ) and acesulfame (ACE) as natural tracers. Furthermore, temperature and electrical conductivity data was used for modeling. The micropollutants are measured using an in house developed online SPE-HPLC-MS/MS method

  3. Applications of the spline filter for areal filtration

    International Nuclear Information System (INIS)

    Tong, Mingsi; Zhang, Hao; Ott, Daniel; Chu, Wei; Song, John

    2015-01-01

    This paper proposes a general use isotropic areal spline filter. This new areal spline filter can achieve isotropy by approximating the transmission characteristic of the Gaussian filter. It can also eliminate the effect of void areas using a weighting factor, and resolve end-effect issues by applying new boundary conditions, which replace the first order finite difference in the traditional spline formulation. These improvements make the spline filter widely applicable to 3D surfaces and extend the applications of the spline filter in areal filtration. (technical note)

  4. Separation of actinides by high-gradient magnetic filtration

    International Nuclear Information System (INIS)

    Bruns, L.E.; Schliebe, M.J.

    1986-01-01

    High-gradient magnetic filtration has been identified as a candidate solid/liquid separation technique for removing actinide particulate from waste streams. Although HGMS is not intended to reduce the activity in the waste stream to below 100 nCi/g, it does offer two significant advantages: (a) selective removal of TRU solids for subsequent secondary processing and (b) reduced operating complications during solvent extraction due to solids accumulation in the interfacial region. Removal of > 95 wt% of the plutonium and americium solids is expected regardless of the solids present and their properties. Verification tests will be performed to validate this assumption

  5. Diacerein niosomal gel for topical delivery: development, in vitro and in vivo assessment.

    Science.gov (United States)

    El-Say, Khalid M; Abd-Allah, Fathy I; Lila, Ahmed E; Hassan, Abd El-Saboor A; Kassem, Alaa Eldin A

    2016-01-01

    The purpose of this study was to load diacerein (DCR) in niosomes by applying response surface methodology and incorporate these niosomes in gel base for topical delivery. Box-Behnken design was used to investigate the effect of charge-inducing agent (X1), surfactant HLB (X2) and sonication time (X3) on the vesicle size (Y1), entrapment efficiency (Y2) and cumulative drug released (Y3). DCR niosomal formulations were prepared by thin film hydration method. The optimized formula was incorporated in different gel bases. DCR niosomal gels were evaluated for homogeneity, rheological behavior; in vitro release and pharmacodynamic activity by carrageenan-induced hind paw edema method in the rat compared with DCR commercial gel. The results revealed that the mean vesicle sizes of the prepared niosomes ranged from 7.33 to 23.72 µm and the entrapment efficiency ranged from 9.52% to 58.43% with controlled release pattern over 8 h. DCR niosomal gels exhibited pseudoplastic flow with thixotropic behavior. The pharmacodynamic activity of DCR niosomal gel in 3% HPMC showed significant, 37.66%, maximum inhibition of edema size in comparison with 20.83% for the commercial gel (p < 0.05). These results recommended the incorporation of DCR niosomes in 3% HPMC for topical application as a potent anti-inflammatory drug for the treatment of osteoarthritis.

  6. Development of hydroxyapatite-chitosan gel sunscreen combating clinical multidrug-resistant bacteria

    Science.gov (United States)

    Morsy, Reda; Ali, Sameh S.; El-Shetehy, Mohamed

    2017-09-01

    The several harmful effects on infected human skin resulting from exposure to the sun's UV radiation generate an interest in the development of a multifunctional hydroxyapatite-chitosan (HAp-chitosan) gel that works as an antibacterial sunscreen agent for skin care. In this work, HAp-chitosan gel was synthesized via coprecipitation method by dissolving chitosan in phosphoric acid and adding HAp. The characteristics of HAp-chitosan composite were investigated by conventional techniques, such as XRD, FTIR, and SEM techniques, while its sunscreen property was investigated by UV-spectroscopy. In addition to the influence of the gel on bacterial cell morphology, the antibacterial activity of HAp-chitosan gel against clinical multidrug resistant skin pathogens, such as Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa has been studied. The results revealed the formation of HAp-chitosan gel having nanosized particles, which confers protection against UV-radiation. The antibacterial activity records showed that chitosan-HAp gel exhibits a significant effect on the growth and ultrastructure of multi-drug resistant bacterial activities. Therefore, the chitosan-HAp gel is promising for skin health care as an antibacterial sunscreen.

  7. Radiation sensitive polymer gel dosimeters

    International Nuclear Information System (INIS)

    Lepage, M.; Back, S.A.J.; Baldock, C.; Whittaker, A.K.; Rintoul, L.

    2000-01-01

    Full text: Radiation sensitive gels are studied for their potential to retain a permanent 3D dose distribution for applications in radiotherapy. Co-monomers dissolved in a tissue-equivalent hydrogel undergo a polymerization reaction upon absorption of ionizing radiation. The polymer formed influences the local spin-spin relaxation time (T 2 ) of the dosimeter that can be determined using magnetic resonance imaging (MRI). The relationship between T2 and the absorbed dose was studied for different initial chemical compositions. The aim was to find a model linking the changes in T 2 with absorbed dose to the initial composition of the dosimeter. It is believed this will help designing new gel dosimeters having desired properties to minimize the uncertainty in the determination of the dose distribution. 1 H, 13 C nuclear magnetic resonance spectroscopy and FT-Raman spectroscopy were used to quantify the amount of monomers still remaining after the absorption of a given dose of radiation. This data is used to model the changes of T2 as a function of the absorbed dose. A model of fast exchange of magnetization between three proton pools was used, where the fraction of protons (f x H ) in the x th pool is obtained from the chemical composition of the dosimeter and the apparent T2 of each pool is determined for a given composition. Initially, the protons are contained in two pools; a mobile (mob), which contains the water protons and the monomers protons, and a gelatin (gela) proton pool. The mobile pool is partially depleted as polymer is formed, the protons are transferred into the polymer (pol) pool. In the figure, the experimental data along with the calculated values are plotted for three different monomer concentrations, with the gelatin concentration fixed. The model is seen to provide a good fit to the experimental data

  8. Silica gel matrix immobilized Chlorophyta hydrodictyon africanum ...

    African Journals Online (AJOL)

    Chlorophyta hydrodictyon africanum was immobilized on a silica gel matrix to improve its mechanical properties. The algae-silica gel adsorbent was used for batch sorption studies of a cationic dye, methylene blue (MB). Optimum adsorption was obtained with a dosage of 0.8 g bio sorbent. Results from sorption studies ...

  9. Contaminant containment using polymer gel barriers

    NARCIS (Netherlands)

    Darwish, M.I.M.; Rowe, R.K.; Maarel, van der J.R.C.; Pel, L.; Huinink, H.P.; Zitha, P.L.J.

    2004-01-01

    Polymer gels are well known in the oil industry, but their potential for use as barriers to contaminant transport has not previously received significant study. As a first step, this paper examines the potential for a polyelectrolyte gel to serve as a barrier to the migration of sodium chloride. Two

  10. Serum release boosts sweetness intensity in gels

    NARCIS (Netherlands)

    Sala, G.; Stieger, M.A.; Velde, van de F.

    2010-01-01

    This paper describes the effect of serum release on sweetness intensity in mixed whey protein isolate/gellan gum gels. The impact of gellan gum and sugar concentration on microstructure, permeability, serum release and large deformation properties of the gels was determined. With increasing gellan

  11. Fast Processing of Sol-Gel TCO

    NARCIS (Netherlands)

    Deelen, J. van; Rem, M.; Arfsten, N.; Buskens, P.P.

    2016-01-01

    TCOs are usually deposited using sputtering or chemical vapor deposition, which have a yield of typically 50-75%. The sol gel method does not need low pressure and can be done with a high precursor yield in the range of 90 – 100%. Sol gel enables also the TCO function as a planarization or

  12. Mathematics revealed

    CERN Document Server

    Berman, Elizabeth

    1979-01-01

    Mathematics Revealed focuses on the principles, processes, operations, and exercises in mathematics.The book first offers information on whole numbers, fractions, and decimals and percents. Discussions focus on measuring length, percent, decimals, numbers as products, addition and subtraction of fractions, mixed numbers and ratios, division of fractions, addition, subtraction, multiplication, and division. The text then examines positive and negative numbers and powers and computation. Topics include division and averages, multiplication, ratios, and measurements, scientific notation and estim

  13. Meso-Decorated Switching-Knot Gels

    Science.gov (United States)

    Gong, Jin; Sawamura, Kensuke; Makino, Masato; Kabir, M. H.; Furukawa, Hidemitsu

    Gels are a new material having three-dimensional network structures of macromolecules. They possess excellent properties as swellability, high permeability and biocompatibility, and have been applied in various fields of daily life, food, medicine, architecture, and chemistry .In this study, we tried to prepare new multi-functional and high-strength gels by using Meso-Decoration (Meso-Deco), one new method of structure design at intermediate mesoscale. High-performance rigid-rod aromatic polymorphic crystals. The strengthening of gels can be realized by meso-decorating the gels' structure using high-performance polymorphic crystals. New gels with good mechanical properties, novel optical properties and thermal properties are expected to be developed.

  14. Polymer architecture of magnetic gels: a review

    Science.gov (United States)

    Weeber, Rudolf; Hermes, Melissa; Schmidt, Annette M.; Holm, Christian

    2018-02-01

    In this review article, we provide an introduction to ferrogels, i.e. polymeric gels with embedded magnetic particles. Due to the interplay between magnetic and elastic properties of these materials, they are promising candidates for engineering and biomedical applications such as actuation and controlled drug release. Particular emphasis will be put on the polymer architecture of magnetic gels since it controls the degrees of freedom of the magnetic particles in the gel, and it is important for the particle-polymer coupling determining the mechanisms available for the gel deformation in magnetic fields. We report on the different polymer architectures that have been realized so far, and provide an overview of synthesis strategies and experimental techniques for the characterization of these materials. We further focus on theoretical and simulational studies carried out on magnetic gels, and highlight their contributions towards understanding the influence of the gels’ polymer architecture.

  15. On shear rheology of gel propellants

    Energy Technology Data Exchange (ETDEWEB)

    Rahimi, Shai; Peretz, Arie [RAFAEL, MANOR Propulsion and Explosive Systems Division, Haifa (Israel); Natan, Benveniste [Faculty of Aerospace Engineering, Technion - Israel Institute of Technology, Haifa (Israel)

    2007-04-15

    Selected fuel, oxidizer and simulant gels were prepared and rheologically characterized using a rotational rheometer. For fuel gelation both organic and inorganic gellants were utilized, whereas oxidizers and simulants were gelled with addition of silica and polysaccharides, respectively. The generalized Herschel-Bulkley constitutive model was found to most adequately represent the gels studied. Hydrazine-based fuels, gelled with polysaccharides, were characterized as shear-thinning pseudoplastic fluids with low shear yield stress, whereas inhibited red-fuming nitric acid (IRFNA) and hydrogen peroxide oxidizers, gelled with silica, were characterized as yield thixotropic fluids with significant shear yield stress. Creep tests were conducted on two rheological types of gels with different gellant content and the results were fitted by Burgers-Kelvin viscoelastic constitutive model. The effect of temperature on the rheological properties of gel propellant simulants was also investigated. A general rheological classification of gel propellants and simulants is proposed. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  16. Complex biological testing of ground water quality in the area of sewage settler filtration fields of JSC 'Almaty Kanty'

    International Nuclear Information System (INIS)

    Vetrinskaya, N.I.; Goldobina, E.A.; Kosmukhambetov, A.R.; Kulikova, O.V.; Kozlova, N.V.; Ismailova, Zh.B.

    2001-01-01

    Results are given on the ground water ecological quality estimation of operating survey boreholes of JSC 'Almaty Kanty' industrial enterprise filtration fields using different methods of biological testing. Proved that various biological objects reacted differently onto the toxins present in the water. Concealment of toxic effect was performed at short-period testing at several testing objects (stimulation). Revealed during long period tests, that ground water from all the boreholes surveyed is not ecologically clean and pure, and can bring damage for ecosystem of water reservoirs adjacent and sources of drinking water if migration happens. (author)

  17. Dip coating of sol-gels

    Science.gov (United States)

    Schunk, P. R.; Hurd, A. J.; Brinker, C. J.

    Dip coating is the primary means of depositing sol-gel films for precision optical coatings. Sols are typically multicomponent systems consisting of an inorganic phase dispersed in a solvent mixture, with each component differing in volatility and surface tension. This, together with slow coating speeds (less than 1cm/s), makes analysis of the coating process complicated; unlike most high-speed coating methods, solvent evaporation, evolving rheology, and surface tension gradients alter significantly the fluid mechanics of the deposition stage. These phenomena were studied with computer-aided predictions of the flow and species transport fields. The underlying theory involves mass, momentum, and species transport on a domain of unknown shape, with models and constitutive equations for vapor-liquid equilibria and surface tension. Due accounting is made for the unknown position of the free surface, which locates according to the capillary hydrodynamic forces and solvent loss by evaporation. Predictions of the effects of mass transfer, hydrodynamics, and surface tension gradients on final film thickness are compared with ellipsometry measurements of film thickness on a laboratory pilot coater. Although quantitative agreement is still lacking, both experiment and theory reveal that the film profile near the drying line takes on a parabolic shape.

  18. Internal structure analysis of particle-double network gels used in a gel organ replica

    Science.gov (United States)

    Abe, Mei; Arai, Masanori; Saito, Azusa; Sakai, Kazuyuki; Kawakami, Masaru; Furukawa, Hidemitsu

    2016-04-01

    In recent years, the fabrication of patient organ replicas using 3D printers has been attracting a great deal of attention in medical fields. However, the cost of these organ replicas is very high as it is necessary to employ very expensive 3D printers and printing materials. Here we present a new gel organ replica, of human kidney, fabricated with a conventional molding technique, using a particle-double network hydrogel (P-DN gel). The replica is transparent and has the feel of a real kidney. It is expected that gel organ replicas produced this way will be a useful tool for the education of trainee surgeons and clinical ultrasonography technologists. In addition to developing a gel organ replica, the internal structure of the P-DN gel used is also discussed. Because the P-DN gel has a complex structure comprised of two different types of network, it has not been possible to investigate them internally in detail. Gels have an inhomogeneous network structure. If it is able to get a more uniform structure, it is considered that this would lead to higher strength in the gel. In the present study we investigate the structure of P-DN gel, using the gel organ replica. We investigated the internal structure of P-DN gel using Scanning Microscopic Light Scattering (SMILS), a non-contacting and non-destructive.

  19. Electrophoresis of DNA in agarose gels, polyacrylamide gels and in free solution

    Science.gov (United States)

    Stellwagen, Nancy C.

    2009-01-01

    This review describes the electrophoresis of curved and normal DNA molecules in agarose gels, polyacrylamide gels and in free solution. These studies were undertaken to clarify why curved DNA molecules migrate anomalously slowly in polyacrylamide gels but not in agarose gels. Two milestone papers are cited, in which Ferguson plots were used to estimate the effective pore size of agarose and polyacrylamide gels. Subsequent studies on the effect of the electric field on agarose and polyacrylamide gel matrices, DNA interactions with the two gel matrices, and the effect of curvature on the free solution mobility of DNA are also described. The combined results suggest that the anomalously slow mobilities observed for curved DNA molecules in polyacrylamide gels are due primarily to preferential interactions of curved DNAs with the polyacrylamide gel matrix; the restrictive pore size of the matrix is of lesser importance. In free solution, DNA mobilities increase with increasing molecular mass until leveling off at a plateau value of (3.17 ± 0.01) × 10-4 cm2/Vs in 40 mM Tris-acetate-EDTA buffer at 20°C. Curved DNA molecules migrate anomalously slowly in free solution as well as in polyacrylamide gels, explaining why the Ferguson plots of curved and normal DNAs containing the same number of base pairs extrapolate to different mobilities at zero gel concentration. PMID:19517510

  20. Organo-clay/anthracite filtration for oil removal

    International Nuclear Information System (INIS)

    Moazed, H.; Viragahavan, T.

    1999-01-01

    An advantage of organo-clay compared to other sorbents is that it can selectively remove organic pollutants from contaminated waters. An investigation was conducted to determine the potential of an organo-clay/anthracite mixture as a filter media for the removal of oil from synthetic and real oily waters. Also included in the study were column filtration studies using synthetic and real waste waters to determine the sorptive capacity of the material. In general, oil removal efficiencies in a 300 mm organo-clay/anthracite bed decreased with an increase in flow rates. Results of eight hour studies indicated that the depth of an organo-clay/anthracite bed has a direct effect on oil removal efficiency. The Thomas equation provides a reasonable fit of the data based on breakthrough studies. The model can be used to determine the parameters needed to design full-scale filtration columns. The uptake of oil by an organo-clay/anthracite mixture is well described by an equation including time such as the Weber or Moris model. The maximum solid-phase concentration of the solute values obtained from the Thomas equation were comparable to the values found by a mass balance approach. 12 refs., 8 figs., 4 tabs

  1. Removal of actinides from dilute waste waters using polymer filtration

    International Nuclear Information System (INIS)

    Smith, B.F.; Robison, T.W.; Gibson, R.R.

    1995-01-01

    More stringent US Department of Energy discharge regulations for waste waters containing radionuclides (30 pCi/L total alpha) require the development of new processes to meet the new discharge limits for actinide metal ions, particularly americium and plutonium, while minimizing waste. We have been investigating a new technology, polymer filtration, that has the potential for effectively meeting these new limits. Traditional technology uses basic iron precipitation which produces large amounts of waste sludge. The new technology is based on using water-soluble chelating polymers with ultrafiltration for physical separation. The actinide metal ions are selectively bound to the polymer and can not pass through the membrane. Small molecules and nonbinding metals pass through the membrane. Advantages of polymer filtration technology compared to ion, exchange include rapid kinetics because the binding is occurring in a homogenous solution and no mechanical strength requirement on the polymer. We will present our results on the systematic development of a new class of water-soluble chelating polymers and their binding ability from dilute acid to near neutral waters

  2. Numerical investigation of adhesion effects on solid particles filtration efficiency

    Science.gov (United States)

    Shaffee, Amira; Luckham, Paul; Matar, Omar K.

    2017-11-01

    Our work investigate the effectiveness of particle filtration process, in particular using a fully-coupled Computational Fluid Dynamics (CFD) and Discrete Element Method (DEM) approach involving poly-dispersed, adhesive solid particles. We found that an increase in particle adhesion reduces solid production through the opening of a wire-wrap type filter. Over time, as particle agglomerates continuously deposit on top of the filter, layer upon layer of particles is built on top of the filter, forming a particle pack. It is observed that with increasing particle adhesion, the pack height build up also increases and hence decreases the average particle volume fraction of the pack. This trend suggests higher porosity and looser packing of solid particles within the pack with increased adhesion. Furthermore, we found that the pressure drop for adhesive case is lower compared to non-adhesive case. Our results suggest agglomerating solid particles has beneficial effects on particle filtration. One important application of these findings is towards designing and optimizing sand control process for a hydrocarbon well with excessive sand production which is major challenge in oil and gas industry. Funding from PETRONAS and RAEng UK for Research Chair (OKM) gratefully acknowledged.

  3. Asymptotics of the filtration problem for suspension in porous media

    Directory of Open Access Journals (Sweden)

    Kuzmina Ludmila Ivanovna

    2015-01-01

    Full Text Available The mechanical-geometric model of the suspension filtering in the porous media is considered. Suspended solid particles of the same size move with suspension flow through the porous media - a solid body with pores - channels of constant cross section. It is assumed that the particles pass freely through the pores of large diameter and are stuck at the inlet of pores that are smaller than the particle size. It is considered that one particle can clog only one small pore and vice versa. The particles stuck in the pores remain motionless and form a deposit. The concentrations of suspended and retained particles satisfy a quasilinear hyperbolic system of partial differential equations of the first order, obtained as a result of macro-averaging of micro-stochastic diffusion equations. Initially the porous media contains no particles and both concentrations are equal to zero; the suspension supplied to the porous media inlet has a constant concentration of suspended particles. The flow of particles moves in the porous media with a constant speed, before the wave front the concentrations of suspended and retained particles are zero. Assuming that the filtration coefficient is small we construct an asymptotic solution of the filtration problem over the concentration front. The terms of the asymptotic expansions satisfy linear partial differential equations of the first order and are determined successively in an explicit form. It is shown that in the simplest case the asymptotics found matches the known asymptotic expansion of the solution near the concentration front.

  4. Granular filtration for airborne particles : correlation between experiments and models

    Energy Technology Data Exchange (ETDEWEB)

    Golshahi, L.; Tan, Z. [Calgary Univ., AB (Canada). Schulich School of Engineering, Mechanical and Manufacturing Dept.; Abedi, J. [Calgary Univ., AB (Canada). Schulich School of Engineering, Chemical and Petroleum Engineering Dept.

    2009-10-15

    A new design for a packed bed granular filter was presented. The cylindrical packed bed was designed to filter particles in the range of approximately 10 nm to 15 {mu}m in diameter in different kinetic conditions and configurations. The aim of the study was to develop a precise empirical model to predict the filtration efficiency of the packed beds. A collision-type atomizer was used to generate polydisperse sodium chloride aerosol particles. The effect of flow rates was studied using a thermal mass flow meter. A regression analysis technique was used to determine the correlation between single granule and total packed bed efficiency for the entire granular filter. The experimental data were then compared with results obtained from the theoretical analysis. The least square method was used to correlate experimental data and to develop generalized equations for single granule efficiency. The study showed that the granular filter media has a high filtration efficiency for both micron and submicron particles. It was concluded that the effect of media thickness was more significant at higher flow rates than at lower flow rates. 10 refs., 3 figs.

  5. The PBW Filtration, Demazure Modules and Toroidal Current Algebras

    Directory of Open Access Journals (Sweden)

    Evgeny Feigin

    2008-10-01

    Full Text Available Let L be the basic (level one vacuum representation of the affine Kac-Moody Lie algebra ^g. The m-th space F_m of the PBW filtration on L is a linear span of vectors of the form x_1dots x_lv_0, where l ≤ m, x_i in ^g and v_0 is a highest weight vector of L. In this paper we give two descriptions of the associated graded space L^{gr} with respect to the PBW filtration. The ''top-down'' description deals with a structure of L^{gr} as a representation of the abelianized algebra of generating operators. We prove that the ideal of relations is generated by the coefficients of the squared field e_θ(z2, which corresponds to the longest root θ. The ''bottom-up'' description deals with the structure of L^{gr} as a representation of the current algebra g otimes C[t]. We prove that each quotient F_m/F_{m-1} can be filtered by graded deformations of the tensor products of m copies of g.

  6. Carbon Nanotube Membranes: Synthesis, Properties, and Future Filtration Applications

    Directory of Open Access Journals (Sweden)

    Md. Harun-Or Rashid

    2017-05-01

    Full Text Available Over the course of the past decade, there has been growing interest in the development of different types of membranes composed of carbon nanotubes (CNTs, including buckypapers and composite materials, for an ever-widening range of filtration applications. This article provides an overview of how different types of CNT membranes are prepared and the results obtained from investigations into their suitability for different applications. The latter involve the removal of small particles from air samples, the filtration of aqueous solutions containing organic compounds and/or bacteria, and the separation of individual liquids present in mixtures. A growing number of reports have demonstrated that the incorporation of CNTs into composite membranes confers an improved resistance to fouling caused by biomacromolecules and bacteria. These results are discussed, along with evidence that demonstrates it is possible to further reduce fouling by taking advantage of the inherent conductivity of composite membranes containing CNTs, as well as by using different types of electrochemical stimuli.

  7. Filtrations on Springer fiber cohomology and Kostka polynomials

    Science.gov (United States)

    Bellamy, Gwyn; Schedler, Travis

    2018-03-01

    We prove a conjecture which expresses the bigraded Poisson-de Rham homology of the nilpotent cone of a semisimple Lie algebra in terms of the generalized (one-variable) Kostka polynomials, via a formula suggested by Lusztig. This allows us to construct a canonical family of filtrations on the flag variety cohomology, and hence on irreducible representations of the Weyl group, whose Hilbert series are given by the generalized Kostka polynomials. We deduce consequences for the cohomology of all Springer fibers. In particular, this computes the grading on the zeroth Poisson homology of all classical finite W-algebras, as well as the filtration on the zeroth Hochschild homology of all quantum finite W-algebras, and we generalize to all homology degrees. As a consequence, we deduce a conjecture of Proudfoot on symplectic duality, relating in type A the Poisson homology of Slodowy slices to the intersection cohomology of nilpotent orbit closures. In the last section, we give an analogue of our main theorem in the setting of mirabolic D-modules.

  8. Turbidity removal: Gravel and charcoal as roughing filtration media

    Directory of Open Access Journals (Sweden)

    Josiah A. Adeyemo

    2010-10-01

    Full Text Available Roughing filtration is an important pre-treatment process for wastewater, because it efficiently separates fine solid particles over prolonged periods, without the addition of chemicals. For this study, a pilot plant was designed at Delmas Coal Mine in the Mpumalanga province of South Africa. The design and sizing of the pilot plant was guided by Wegelin’s design criteria. Gravel was used as a control medium because it is one of the most commonly used roughing filter media and because it was used in developing the criteria. We compared the performance of gravel as a filter medium to that of another locally available material, charcoal, for the removal of turbidity in wastewater. The pilot plant was monitored continuously for 90 days from commissioning until the end of the project. The overall performance of the roughing filter in turbidity removal, using gravel or charcoal, was considered efficient for the pre-treatment of waste water. Charcoal performed slightly better than gravel as a filter medium for the removal of turbidity, possibly because charcoal has a slightly higher specific surface area and porosity than gravel, which could enhance sedimentation and other filtration processes, such as adsorption, respectively.

  9. Using the developed cross-flow filtration chip for collecting blood plasma under high flow rate condition and applying the immunoglobulin E detection

    Science.gov (United States)

    Yeh, Chia-Hsien; Hung, Chia-Wei; Wu, Chun-Han; Lin, Yu-Cheng

    2014-09-01

    This paper presents a cross-flow filtration chip for separating blood cells (white blood cells, red blood cells, and platelets) and obtaining blood plasma from human blood. Our strategy is to flow the sample solution in parallel to the membrane, which can generate a parallel shear stress to remove the clogging microparticles on the membrane, so the pure sample solution is obtained in the reservoir. The cross-flow filtration chip includes a cross-flow layer, a Ni-Pd alloy micro-porous membrane, and a reservoir layer. The three layers are packaged in a polymethylmethacrylate (PMMA) frame to create the cross-flow filtration chip. Various dilutions of the blood sample (original, 2 × , 3 × , 5 × , and 10×), pore sizes with different diameters (1 µm, 2 µm, 4 µm, 7 µm, and 10 µm), and different flow rates (1 mL/min, 3 mL/min, 5 mL/min, 7 mL/min, and 10 mL/min) are tested to determine their effects on filtration percentage. The best filtration percentage is 96.2% when the dilution of the blood sample is 10 × , the diameter of pore size of a Ni-Pd alloy micro-porous membrane is 2 µm, and the flow rate is 10 mL/min. Finally, for the clinical tests of the immunoglobulin E (IgE) concentration, the cross-flow filtration chip is used to filter the blood of the allergy patients to obtain the blood plasma. This filtered blood plasma is compared with that obtained using the conventional centrifugation based on the enzyme-linked immunosorbent assay. The results reveal that these two blood separation methods have similar detection trends. The proposed filtration chip has the advantages of low cost, short filtration time, and easy operation and thus can be applied to the separation of microparticles, cells, bacteria, and blood.

  10. Using the developed cross-flow filtration chip for collecting blood plasma under high flow rate condition and applying the immunoglobulin E detection

    International Nuclear Information System (INIS)

    Yeh, Chia-Hsien; Hung, Chia-Wei; Lin, Yu-Cheng; Wu, Chun-Han

    2014-01-01

    This paper presents a cross-flow filtration chip for separating blood cells (white blood cells, red blood cells, and platelets) and obtaining blood plasma from human blood. Our strategy is to flow the sample solution in parallel to the membrane, which can generate a parallel shear stress to remove the clogging microparticles on the membrane, so the pure sample solution is obtained in the reservoir. The cross-flow filtration chip includes a cross-flow layer, a Ni-Pd alloy micro-porous membrane, and a reservoir layer. The three layers are packaged in a polymethylmethacrylate (PMMA) frame to create the cross-flow filtration chip. Various dilutions of the blood sample (original, 2 × , 3 × , 5 × , and 10×), pore sizes with different diameters (1 µm, 2 µm, 4 µm, 7 µm, and 10 µm), and different flow rates (1 mL/min, 3 mL/min, 5 mL/min, 7 mL/min, and 10 mL/min) are tested to determine their effects on filtration percentage. The best filtration percentage is 96.2% when the dilution of the blood sample is 10 × , the diameter of pore size of a Ni-Pd alloy micro-porous membrane is 2 µm, and the flow rate is 10 mL/min. Finally, for the clinical tests of the immunoglobulin E (IgE) concentration, the cross-flow filtration chip is used to filter the blood of the allergy patients to obtain the blood plasma. This filtered blood plasma is compared with that obtained using the conventional centrifugation based on the enzyme-linked immunosorbent assay. The results reveal that these two blood separation methods have similar detection trends. The proposed filtration chip has the advantages of low cost, short filtration time, and easy operation and thus can be applied to the separation of microparticles, cells, bacteria, and blood. (paper)

  11. Antifungal Activity of Culture Filtrates and Organic Extracts of Aspergillus spp. against Pythium ultimum

    OpenAIRE

    Rania Aydi-Ben Abdallah; Marwa Hassine; Hayfa Jabnoun-Khiareddine; Rabiaa Haouala; Mejda Daami-Remadi

    2014-01-01

    Culture filtrates, chloroform and ethyl acetate extracts of nine isolates of Aspergillus spp. (A. niger, A. terreus, A. flavus and Aspergillus sp.), isolated from soil and compost, were tested for antifungal activity against Pythium ultimum the causal agent of the potato Pythium leak. Culture filtrates showed a significant antifungal activity at the different tested concentrations. Total inhibition of the pathogen was induced by the filtrate of CH8 of Aspergillus sp., used at 10% ...

  12. Digital Marketing concept and strategy for a Finnish Start-up, Case: Sofi Filtration

    OpenAIRE

    Buda, Constantin

    2014-01-01

    The case company is a Finnish start-up company that operates in the industrial water filtration business and who aims to increase its brand awareness and generate more sales leads. The aim of this study is to provide effective and inexpensive tools for Sofi Filtration to engage its target audience and grow its business by being acknowledged as an expert in industrial water filtration. The thesis is part of the International Business Management program offered by HAAGA-HELIA University of ...

  13. Noncausal two-stage image filtration at presence of observations with anomalous errors

    OpenAIRE

    S. V. Vishnevyy; S. Ya. Zhuk; A. N. Pavliuchenkova

    2013-01-01

    Introduction. It is necessary to develop adaptive algorithms, which allow to detect such regions and to apply filter with respective parameters for suppression of anomalous noises for the purposes of image filtration, which consist of regions with anomalous errors. Development of adaptive algorithm for non-causal two-stage images filtration at pres-ence of observations with anomalous errors. The adaptive algorithm for noncausal two-stage filtration is developed. On the first stage the adaptiv...

  14. Evolution of heterogeneity accompanying sol-gel transitions in a supramolecular hydrogel.

    Science.gov (United States)

    Matsumoto, Yuji; Shundo, Atsuomi; Ohno, Masashi; Tsuruzoe, Nobutomo; Goto, Masahiro; Tanaka, Keiji

    2017-10-18

    When a peptide amphiphile is dispersed in water, it self-assembles into a fibrous network, leading to a supramolecular hydrogel. When the gel is physically disrupted by shaking, it transforms into a sol state. After aging at room temperature for a while, it spontaneously returns to the gel state, called sol-gel transition. However, repeating the sol-gel transition often causes a change in the rheological properties of the gel. To gain a better understanding of the sol-gel transition and its reversibility, we herein examined the thermal motion of probe particles at different locations in a supramolecular hydrogel. The sol obtained by shaking the gel was heterogeneous in terms of the rheological properties and the extent decreased with increasing aging time. This time course of heterogeneity, or homogeneity, which corresponded to the sol-to-gel transition, was observed for the 1st cycle. However, this was not the case for the 2nd and 3rd cycles; the heterogeneity was preserved even after aging. Fourier-transform infrared spectroscopy, small-angle X-ray scattering, and atomic force and confocal laser scanning microscopies revealed that, although the molecular aggregation states of amphiphiles both in the gel and sol remained unchanged with the cycles, the fibril density diversified to high and low density regions even after aging. The tracking of particles with different sizes indicated that the partial mesh size in the high density region and the characteristic length scale of the density fluctuation were smaller than 50 nm and 6 μm, respectively.

  15. Treatment of secondary effluent by sequential combination of photocatalytic oxidation with ceramic membrane filtration.

    Science.gov (United States)

    Song, Lili; Zhu, Bo; Jegatheesan, Veeriah; Gray, Stephen; Duke, Mikel; Muthukumaran, Shobha

    2018-02-01

    The aim of the present work was to experimentally evaluate an alternative advanced wastewater treatment system, which combines the action of photocatalytic oxidation with ceramic membrane filtration. Experiments were carried out using laboratory scale TiO 2 /UV photocatalytic reactor and tubular ceramic microfiltration (CMF) system to treat the secondary effluent (SE). A 100-nm pore size CMF membrane was investigated in cross flow mode under constant transmembrane pressure of 20 kPa. The results show that specific flux decline of CMF membrane with and without TiO 2 /UV photocatalytic treatment was 30 and 50%, respectively, after 60 min of filtration. Data evaluation revealed that the adsorption of organic compounds onto the TiO 2 particles was dependent on the pH of the suspension and was considerably higher at low pH. The liquid chromatography-organic carbon detector (LC-OCD) technique was used to characterise the dissolved organic matter (DOM) present in the SE and was monitored following photocatalysis and CMF. The results showed that there was no removal of biopolymers and slight removal of humics, building blocks and the other oxidation by-products after TiO 2 /UV photocatalytic treatment. This result suggested that the various ions present in the SE act as scavengers, which considerably decrease the efficiency of the photocatalytic oxidation reactions. On the other hand, the CMF was effective for removing 50% of biopolymers with no further removal of other organic components after photocatalytic treatment. Thus, the quantity of biopolymers in SE has an apparent correlation with the filterability of water samples in CMF.

  16. Lag times of bank filtration at a well field, Cincinnati, Ohio, USA

    Science.gov (United States)

    Sheets, R.A.; Darner, R.A.; Whitteberry, B.L.

    2002-01-01

    Wells placed next to surface-water bodies to induce infiltration have come under scrutiny because of the presence of the potential pathogens in surface water. Removal of pathogens and other contaminants by bank filtration is assumed, but regulatory agencies question the effectiveness of this process. To investigate transport processes of biological constituents, advective groundwater traveltimes to production wells under the influence of surface water need to be established first to determine appropriate water-quality sampling schedules. This paper presents the results of a study of bank filtration at a well field in southwestern Ohio. Field parameters such as water level, specific conductance, and water temperature were measured at least hourly at a streamflow gaging station and at five monitoring wells each at two separate sites, corresponding to two nearby production wells. Water-quality samples also were collected in all wells and the streamflow gaging station. Specific conductance is directly related to concentration of chloride, a chemically conservative constituent. Cross-correlation methods were used to determine the average traveltime from the river to the monitoring wells. Traveltimes based on specific conductance ranged from approximately 20 h to 10 days at one site and 5 days to 3 months at the other site. Calculated groundwater flow velocities ranged from 2.1 ?? 10-3 to 6.0 ?? 10-3 cm/s and 3.5 ?? 10-4 to 7.1 ?? 10-4 cm/s at the two sites. Data collected when a production well is continuously pumping reveal shorter and more consistent traveltimes than when the same well is pumped intermittently. ?? 2002 Elsevier Science B.V. All rights reserved.

  17. Ionic liquid gel materials: applications in green and sustainable chemistry

    OpenAIRE

    Marr, Patricia C.; Marr, Andrew C.

    2016-01-01

    Ionic liquid gel materials offer a way to further utilise ionic liquids in technological applications. Combining the controlled and directed assembly of gels, with the diverse applications of ionic liquids, enables the design of a heady combination of functional tailored materials, leading to the development of task specific / functional ionic liquid gels. This review introduces gels and gel classification, focusing on ionic liquid gels and their potential roles in a more sustainable future. ...

  18. Modeling of filtration of 2-types particles suspension in a porous medium

    Directory of Open Access Journals (Sweden)

    Galaguz Yuri

    2017-01-01

    Full Text Available The filtration problem describes the process of concreting loose soil with a liquefied concrete solution. The filtration of 2-types particles suspension in a homogeneous porous medium with a size-exclusion particles retention mechanism is considered. The difference in the filtration coefficients of 2-types particles leads to the separation of the filtration domain into two zones, in one of which two types of particles are deposited and in another – only particles of one type are deposited. In this paper, the mobile boundary of two zones is calculated, and numerical solution of the problem is calculated.

  19. Evaluation of Isolated Fractions of Aloe vera Gel Materials on Indinavir Pharmacokinetics: In vitro and in vivo Studies.

    Science.gov (United States)

    Wallis, Lonette; Malan, Maides; Gouws, Chrisna; Steyn, Dewald; Ellis, Suria; Abay, Efrem; Wiesner, Lubbe; Otto, Daniel P; Hamman, Josias

    2016-01-01

    Aloe vera is a plant with a long history of traditional medicinal use and is consumed in different products, sometimes in conjunction with prescribed medicines. A. vera gel has shown the ability to modulate drug absorption in vitro. The aim of this study was to fractionate the precipitated polysaccharide component of A. vera gel based on molecular weight and to compare their interactions with indinavir pharmacokinetics. Crude polysaccharides were precipitated from a solution of A. vera gel and was fractionated by means of centrifugal filtration through membranes with different molecular weight cut-off values (i.e. 300 KDa, 100 KDa and 30 KDa). Marker molecules were quantified in the aloe leaf materials by means of nuclear magnetic resonance spectroscopy and the average molecular weight was determined by means of gel filtration chromatography linked to multi-angle-laser-light scattering and refractive index detection. The effect of the aloe leaf materials on the transepithelial electrical resistance (TEER) of Caco-2 cell monolayers as well as indinavir metabolism in LS180 cells was measured. The bioavailability of indinavir in the presence and absence of the aloe leaf materials was determined in Sprague-Dawley rats. All the aloe leaf materials investigated in this study reduced the TEER of Caco-2 cell monolayers, inhibited indinavir metabolism in LS 180 cells to different extents and changed the bioavailability parameters of indinavir in rats compared to that of indinavir alone. These indinavir pharmacokinetic modulation effects were not dependent on the presence of aloverose and also not on the average molecular weight of the isolated fractions.

  20. Sol-gel technology for biomedical engineering

    International Nuclear Information System (INIS)

    Podbielska, H.; Ulatowska-Jarza, A.

    2005-01-01

    Sol-gel derived silica possess many promising features, including low-temperature preparation procedure, porosity, chemical and physical stability. Applications exploiting porous materials to encapsulate sensor molecules, enzymes and many other compounds, are developing rapidly. In this paper some potential applications, with emphasis on biomedical and environmental ones, are reviewed. The material preparation procedure is described and practical remarks on silica-based sol-gels are included. It is reported that sol-gels with entrapped various molecules may be used in construction of implants and coatings with bioactive properties. It is shown how to exploit the sol-gel production route for construction of sol-gel coated fiberoptic applicators for laser therapy. The applications of bioactive materials are discussed, as well. It is demonstrated that it is possible to immobilize photosensitive compounds in sol-gel matrix without loosing their photoactivity. Some examples of sol-gel based biosensors are demonstrated, as well, showing their potential for detecting various gases, toxic substances, acidity, humidity, enzymes and biologically active agents. (authors)

  1. Sol-Gel Manufactured Energetic Materials

    Science.gov (United States)

    Simpson, Randall L.; Lee, Ronald S.; Tillotson, Thomas M.; Hrubesh, Lawrence W.; Swansiger, Rosalind W.; Fox, Glenn A.

    2005-05-17

    Sol-gel chemistry is used for the preparation of energetic materials (explosives, propellants and pyrotechnics) with improved homogeneity, and/or which can be cast to near-net shape, and/or made into precision molding powders. The sol-gel method is a synthetic chemical process where reactive monomers are mixed into a solution, polymerization occurs leading to a highly cross-linked three dimensional solid network resulting in a gel. The energetic materials can be incorporated during the formation of the solution or during the gel stage of the process. The composition, pore, and primary particle sizes, gel time, surface areas, and density may be tailored and controlled by the solution chemistry. The gel is then dried using supercritical extraction to produce a highly porous low density aerogel or by controlled slow evaporation to produce a xerogel. Applying stress during the extraction phase can result in high density materials. Thus, the sol-gel method can be used for precision detonator explosive manufacturing as well as producing precision explosives, propellants, and pyrotechnics, along with high power composite energetic materials.

  2. Sol-gel bonding of silicon wafers

    International Nuclear Information System (INIS)

    Barbe, C.J.; Cassidy, D.J.; Triani, G.; Latella, B.A.; Mitchell, D.R.G.; Finnie, K.S.; Short, K.; Bartlett, J.R.; Woolfrey, J.L.; Collins, G.A.

    2005-01-01

    Sol-gel bonds have been produced between smooth, clean silicon substrates by spin-coating solutions containing partially hydrolysed silicon alkoxides. The two coated substrates were assembled and the resulting sandwich fired at temperatures ranging from 60 to 600 deg. C. The sol-gel coatings were characterised using attenuated total reflectance Fourier transform infrared spectroscopy, ellipsometry, and atomic force microscopy, while the corresponding bonded specimens were investigated using scanning electron microscopy and cross-sectional transmission electron microscopy. Mechanical properties were characterised using both microindentation and tensile testing. Bonding of silicon wafers has been successfully achieved at temperatures as low as 60 deg. C. At 300 deg. C, the interfacial fracture energy was 1.55 J/m 2 . At 600 deg. C, sol-gel bonding provided superior interfacial fracture energy over classical hydrophilic bonding (3.4 J/m 2 vs. 1.5 J/m 2 ). The increase in the interfacial fracture energy is related to the increase in film density due to the sintering of the sol-gel interface with increasing temperature. The superior interfacial fracture energy obtained by sol-gel bonding at low temperature is due to the formation of an interfacial layer, which chemically bonds the two sol-gel coatings on each wafer. Application of a tensile stress on the resulting bond leads to fracture of the samples at the silicon/sol-gel interface

  3. Polymer gel dosimeter with AQUAJOINT® as hydrogel matrix

    Science.gov (United States)

    Maeyama, Takuya; Ishida, Yasuhiro; Kudo, Yoshihiro; Fukasaku, Kazuaki; Ishikawa, Kenichi L.; Fukunishi, Nobuhisa

    2018-05-01

    We report a polymer gel dosimeter based on a new gel matrix (AQUAJOINT®) that is a thermo-irreversible hydrogel formed by mixing two types of water-based liquids at room temperature. Normoxic N-vinylpyrrolidone-based polymer gels were prepared with AQUAJOINT® instead of gelatin. This AQUAJOINT®-based gel dosimeter exhibits a 2.5-fold increase in sensitivity over a gelatin-based gel dosimeter and a linear dose-response in the dose range of 0-8 Gy. This gel has heat resistance in a jar and controlled gel properties such as viscoelastic and mechanical characters, which may be useful for deformable polymer gel dosimetry.

  4. Computational design of active, self-reinforcing gels.

    Science.gov (United States)

    Yashin, Victor V; Kuksenok, Olga; Balazs, Anna C

    2010-05-20

    Many living organisms have evolved a protective mechanism that allows them to reversibly alter their stiffness in response to mechanical contact. Using theoretical modeling, we design a mechanoresponsive polymer gel that exhibits a similar self-reinforcing behavior. We focus on cross-linked gels that contain Ru(terpy)(2) units, where both terpyridine ligands are grafted to the chains. The Ru(terpy)(2) complex forms additional, chemoresponsive cross-links that break and re-form in response to a repeated oxidation and reduction of the Ru. In our model, the periodic redox variations of the anchored metal ion are generated by the Belousov-Zhabotinsky (BZ) reaction. Our computer simulations reveal that compression of the BZ gel leads to a stiffening of the sample due to an increase in the cross-link density. These findings provide guidelines for designing biomimetic, active coatings that send out a signal when the system is impacted and use this signaling process to initiate the self-protecting behavior.

  5. Smectic liquid crystals in anisotropic colloidal silica gels

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Dennis [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Borthwick, Matthew A [Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Leheny, Robert L [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States)

    2004-05-19

    We report x-ray scattering studies of the smectic liquid crystal octylcyano-biphenol (8CB) confined by strained colloidal silica gels. The gels, comprised of aerosil particles, possess an anisotropic structure that stabilizes long-range nematic order in the liquid crystal while introducing random field effects that disrupt the smectic transition. The short-range smectic correlations that form within this environment are inconsistent with the presence of a topologically ordered state predicted for 3D random field XY systems and are quantitatively like the correlations of smectics confined by isotropic gels. Detailed analysis reveals that the quenched disorder suppresses the anisotropic scaling of the smectic correlation lengths observed in the pure liquid crystal. These results and additional measurements of the smectic-A to smectic-C transition in 4-n-pentylphenylthiol-4'-n-octyloxybenzoate (8barS5) indicate that the observed smectic behaviour is dictated by random fields coupling directly to the smectic order while fields coupling to the nematic director play a subordinate role.

  6. Suitability assessment of grey water quality treated with an upflow-downflow siliceous sand/marble waste filtration system for agricultural and industrial purposes.

    Science.gov (United States)

    Chaabane, Safa; Riahi, Khalifa; Hamrouni, Hédi; Thayer, Béchir Ben

    2017-04-01

    The present study examines the suitability assessment of an upflow-downflow siliceous sand/marble waste filtration system for treatment and reuse of grey water collected from bathrooms of the student residential complex at the Higher Institute of Engineering Medjez El Bab (Tunisia). Once the optimization of grey water pre-treatment system has been determined, the filtration system was operated at different hydraulic loading rate and media filter proportions in order to assess the suitability of treated grey water for irrigational purpose according to salinity hazard, sodium hazard, magnesium hazard, permeability index, water infiltration rate, and widely used graphical methods. Suitability of the treated grey water for industrial purpose was evaluated in terms of foaming, corrosion, and scaling. Under optimal operational conditions, results reveals that treated grey water samples with an upflow-downflow siliceous sand/marble waste filtration system may be considered as a good and an excellent water quality suitable for irrigation purpose. However, treated grey water was found not appropriate for industrial purpose due to high concentrations of calcium and sodium that can generate foaming and scaling harm to boilers. These results suggest that treated grey water with an upflow-downflow siliceous sand/marble waste filtration system would support production when used as irrigation water.

  7. Treatment of exhausted tannin liquors of the leather industry by nano filtration; Tratamiento por nanofiltracion de los licores agotados de taninos en la industria del curtido

    Energy Technology Data Exchange (ETDEWEB)

    Adzet, J.; Buonomenna, M. G.; Cassano, A.; Drioli, E.; Molineri, R.

    2002-07-01

    The use of a nano filtration process is described in order to rationalize the vegetable tonnage step in leather industry through the recovery of tannins from the exhausted baths and their reuse as tanning agents. The results obtained on pilot scale using a membrane module, identified after a screening of various nano filtration membranes, the operating and fluid-dynamic conditions and the mass balance of the nano filtration process are reported and discussed. Skins treated with the recovered solutions revealed chemical and physical parameters very similar to those measured on control skins tanned with standard solutions. According to the obtained results, it is possible to suggest a process scheme that, starting from the exhausted tanning baths, through a nano filtration membrane purification/concentration, permits to increase the tannin/non tannin ratio of the retentate solution. Advantages are in terms of: reduction of environmental impact, simplification of cleaning-up processes of wastewaters, decrease of disposal costs, saving of chemicals and water. (Author)

  8. Acoustic evaluation of polymer gel dosimeters

    International Nuclear Information System (INIS)

    Mather, M.L.; De Deene, Y.; Baldock, C.; Whittaker, A.K.

    2002-01-01

    Advances in radiotherapy treatment techniques such as intensity modulated radiotherapy are placing increasing demands on radiation dosimetry for verification of dose distributions in 3D. In response, polymer gel dosimeters that are capable of recording dose distributions in 3D are currently being developed. Recently, a new technique for evaluation of absorbed dose distributions in these dosimeters using ultrasound was introduced. The current work aims to demonstrate the potential of ultrasound as an evaluation technique for polymer gel dosimeters and to investigate the ultrasound properties of two different dosimeter formulations, PAG and MAGIC gels

  9. Pulsed field gel electrophoresis a practical guide

    CERN Document Server

    Birren, Bruce

    1993-01-01

    Pulsed Field Gel Electrophoresis: A Practical Guide is the first laboratory manual to describe the theory and practice of this technique. Based on the authors' experience developing pulsed field gel instruments and teaching procedures, this book provides everything a researcher or student needs to know in order to understand and carry out pulsed field gel experiments. Clear, well-tested protocols assume only that users have a basic familiarity with molecular biology. Thorough coverage of useful data, theory, and applications ensures that this book is also a lasting resource for more adv

  10. Applications of sol gel ceramic coatings

    International Nuclear Information System (INIS)

    Barrow, D.

    1996-01-01

    The sol gel method is a chemical technique in which polycrystalline ceramic films are fabricated from a solution of organometallic precursors. The technique is attractive for many industrial applications because it is a simple (films are processed in air), flexible (can be used to coat complex geometries) and cost effective (does not require expensive equipment) process. In addition, dense, high quality coatings can be achieved at much lower temperatures than is generally required for sintering bulk ceramics. In this paper the conventional sol gel method and the new datec process are reviewed and potential applications of sol gel coatings in automotive, aerospace, petrochemical, nuclear and electronic industries are discussed. (orig.)

  11. Synthesis of lithium doped zinc oxide by sol gel

    International Nuclear Information System (INIS)

    Meziane, K; Elhichou, A; Elhamidi, A; Almaggoussi, A; CHHIBA, M

    2016-01-01

    Li-doped ZnO thin films were prepared by sol-gel method and deposed on glass substrate using spin coating technique. The effects of Li on structural and optical properties were investigated. The X-ray diffraction (XRD) analysis reveals that Li incorporation leads to the great improvement of the crystalline quality of ZnO thin films. Scanning electron microscopy (SEM) images showed that nanowires are aligned nearly perpendicular to the substrate plane and are affected significantly by Li incorporation. The optical transmission of the films was higher than 80% in the visible region. It is found that the optical gap and the refractive index remain practically constant. (paper)

  12. Liquid filtration properties in gravel foundation of railroad tracks

    International Nuclear Information System (INIS)

    Strelkov, A; Teplykh, S; Bukhman, N

    2016-01-01

    Railway bed gravel foundation has a constant permanent impact on urban ecology and ground surface. It is only natural that larger objects, such as railway stations, make broader impact. Surface run-off waters polluted by harmful substances existing in railroad track body (ballast section) flow along railroad tracks and within macadam, go down into subterranean ground flow and then enter neighbouring rivers and water basins. This paper presents analytic calculations and characteristics of surface run-off liquid filtration which flows through gravel multiple layers (railroad track ballast section). The authors analyse liquids with various density and viscosity flowing in multi-layer porous medium. The paper also describes liquid stationary and non-stationary weepage into gravel foundation of railroad tracks. (paper)

  13. High efficiency filtration of liquid-metal-generated aerosols

    International Nuclear Information System (INIS)

    First, M.W.

    1977-01-01

    This paper will present data on filter performance for the range of sodium-containing aerorols that can result from large and small releases of hot metallic sodium into confined spaces containing air or special atmospheres and will compare the particle collection effectiveness, space and power requirements, service life, and disposal of the collected materials for the several options. Prompt reduction of in-vessel aerosols with methods that induce rapid coagulation and sedimentation by the application of violent turbulance, sonic energy, or electrostatic attraction; by aerosol scavenging with massive inert dust additions; and by a number of other innovative methods is of special interest because of their potential ability to bring down the aerosol cloud very rapidly and thereby to reduce vessel out-leakage drastically; as well as to relieve the particle load on filters. These methods will be examined as supplements to filtration methods for control of sodium-containing aerosols

  14. Organic-inorganic membranes for filtration of corn distillery

    Directory of Open Access Journals (Sweden)

    Myronchuk Valeriy G.

    2016-01-01

    Full Text Available Organic-inorganic membranes were obtained by modification of polymer microfiltration membrane with inorganic ion-exchangers, which form secondary porosity inside macroporous substrate (zirconium hydrophosphate or simultaneously in the macroporous substrate and active layer, depending of the particle size (from ≈50 nm up to several microns. Precipitation of the inorganic constituent is considered from the point of view of Ostwald-Freundlich equation. Such processes as pressing test in deionized water and filtration of corn distillery at 1-6 bar were investigated. Theoretical model allowing to establish fouling mechanism, was applied. It was found that the particles both in the substrate and active layer prevent fouling of the membrane with organics and provide rejection of colloidal particles.

  15. Secondary waste characteristics and ITS filtration system on laser cutting

    Energy Technology Data Exchange (ETDEWEB)

    Hara, Kunio; Miyao, Hidehiko [Research Association for Facility Decommissioning (RANDEC), Tokai, Ibaraki (Japan); Nakazawa, Masaharu [Tokyo Univ. (Japan); Kataoka, Shinichi; Nagura, Yasumi; Saiki, Hideo [Mitsubishi Heavy Industries Ltd., Tokyo (Japan)

    2001-03-01

    Technology of dismantling nuclear facilities has been developing in various fields for its evaluation and dismantling system. RANDEC has been studying remote dismantling system for highly activated equipments such as core internals with a laser using optical fiber. Recently a high power YAG laser having the advantage of application for remote dismantling on thick metallic material is the stage for practical use, and narrow kerf can bring the reduction of secondary waste as well. The present paper describes the experimental results and discussion on the laser cutting, including the secondary waste characteristics and its filtration system using the YAG laser. This study has been performed on consignment to RANDEC from the Science and Technology Agency of Japan. (author)

  16. Formation and filtration of flocs from coal slurries

    Energy Technology Data Exchange (ETDEWEB)

    Singh, B K

    1977-06-01

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

  17. Dynamics of intrarenal pressures and glomerular filtration rate after acetazolamide

    DEFF Research Database (Denmark)

    Leyssac, P P; Karlsen, F M; Skøtt, O

    1991-01-01

    -EDTA and lithium. Proximal tubular pressure (Pprox) increased initially by 1.7 +/- 0.1 mmHg after ACZ, causing a decrease in the hydrostatic pressure difference across the glomerular membrane (delta P). EDC increased, and then RBF, glomerular capillary pressure (Pgc), Pprox, and star vessel pressures (Psv) dropped......The dynamics of intrarenal pressures, early distal tubular fluid conductivity (EDC), and renal flood flow (RBF) were studied in rats given acetazolamide (ACZ), an inhibitor of proximal reabsorption. Glomerular filtration rate (GFR) and end-proximal flow were estimated by clearances of 51Cr...... as a result of afferent vasoconstriction. Pprox decreased less than Pgc, resulting in a further decrease in delta P, which after 25-30 s reached a constant level 3-4 mmHg below control. After a transient increase the pressures declined to a new steady state, in which Pprox was equal to control, Pgc...

  18. Is the use of particle air filtration justified? Costs and benefits of filtration with regard to health effects, building cleaning and occupant productivity

    DEFF Research Database (Denmark)

    Bekö, Gabriel; Clausen, Geo; Weschler, Charles J.

    2008-01-01

    Estimates of costs and the corresponding benefits of particle filtration have been derived for a standard office building. Reduction in occupants’ exposure to particles during their workday is anticipated to reduce their morbidity and mortality. Filtration may also reduce the costs associated......, the sensitivity of the results to these parameters was evaluated as part of this study. The study also acknowledges that the benefits-to-costs ratio depends on the perspective of the stakeholder: the employer renting the building is impacted by occupant performance and building energy costs; the building owner...... is impacted by maintenance of the building and its HVAC system; society is impacted by the employees’ health and welfare. Regardless of perspective, particle filtration is anticipated to lead to annual savings significantly exceeding the running costs for filtration. However, economic losses resulting from...

  19. Modified thermoresponsive Poloxamer 407 and chitosan sol-gels as potential sustained-release vaccine delivery systems

    DEFF Research Database (Denmark)

    Kojarunchitt, Thunjiradasiree; Baldursdottir, Stefania; Dong, Yao-Da

    2015-01-01

    Thermoresponsive, particle-loaded, Poloxamer 407 (P407)-Pluronic-R® (25R4) or chitosan-methyl cellulose (MC) formulations were developed as single-dose, sustained release vaccines. The sol-gels, loaded either with a particulate vaccine (cubosomes) or soluble antigen (ovalbumin) and adjuvants (Quil...... the chitosan-MC sol-gels sustained the release of antigen up to at least 14 days after administration. The chitosan-MC sol-gels stimulated both cellular and humoral responses. The inclusion of cubosomes in the sol-gels did not provide a definitive beneficial effect. Further analysis of the formulations...... with small-angle X-ray scattering (SAXS) revealed that while cubosomes were stable in chitosan-MC gels they were not stable in P407-25R4 formulations. The reason for the mixed response to cubosome-loaded vehicles requires more investigation, however it appears that the cubosomes did not facilitate...

  20. Behavior of Gd-DTPA in simulated bank filtration

    International Nuclear Information System (INIS)

    Moeller, Peter; Knappe, Andrea; Dulski, Peter; Pekdeger, Asaf

    2011-01-01

    Research highlights: → Gd-DTPA and similar products are common pollutants in surface and groundwater and prove to be a reliable monitor for mixing of groundwater with surface water loaded with effluents from sewage treatment plants. → Within a 30 m column filled with Pleistocene sand Gd-DTPA is reduced by 16% only within one month time by transmetallation. → Artificial bank filtration is not very effective in reducing Gd-DTPA in infiltrating water. - Abstract: The behavior of Gd-DTPA during bank filtration was simulated in a 30 m column filled with Pleistocene sand and flushed by surface water from a lakeside in Berlin, Germany. The surface water is about a 1:1 mixture of river water and effluents from a sewage treatment plant. Throughout 34 days this water was continuously spiked with Gd-DTPA at a level of 60 μg/L. The broad plateau of the Gd-DTPA pulse declined by 15.4% within 34 days by transmetallation. Nine percentage of the total decline is caused by Y and rare earth elements; the remaining part is attributed to Cu 2+ which is the most influential metal in surface water. All other metals also contributing to transmetallation are combined with Cu to Cu equivalents because only the rate constant of transmetallation of Cu 2+ is known. The analytical results of the column effluents prove the pseudo-first-order kinetics of transmetallation based on reversible sorption of metals by pools in the column sediment and disprove biodegradation at noticeable levels. The mass ratio of water to tracer is 10 .

  1. Experimental study of head loss and filtration for LOCA debris

    International Nuclear Information System (INIS)

    Rao, D.V.; Souto, F.J.

    1996-02-01

    A series of controlled experiments were conducted to obtain head loss and filtration characteristics of debris beds formed of NUKON trademark fibrous fragments, and obtain data to validate the semi-theoretical head loss model developed in NUREG/CR-6224. A thermally insulated closed-loop test set-up was used to conduct experiments using beds formed of fibers only and fibers intermixed with particulate debris. A total of three particulate mixes were used to simulate the particulate debris. The head loss data were obtained for theoretical fiber bed thicknesses of 0.125 inches to 4.0 inches; approach velocities of 0.15 to 1.5 ft/s; temperatures of 75 F and 125 F; and sludge-to-fiber nominal concentration ratios of 0 to 60. Concentration measurements obtained during the first flushing cycle were used to estimate the filtration efficiencies of the debris beds. For test conditions where the beds are fairly uniform, the head loss data were predictable within an acceptable accuracy range by the semi-theoretical model. The model was equally applicable for both pure fiber beds and the mixed beds. Typically the model over-predicted the head losses for very thin beds and for thin beds at high sludge-to-fiber mass ratios. This is attributable to the non-uniformity of such debris beds. In this range the correlation can be interpreted to provide upper bound estimates of head loss. This is pertinent for loss of coolant accidents in boiling water reactors

  2. Emergency field water supply system using natural filtration elements

    Science.gov (United States)

    Vikneswaran, M.; Yahya, Muhamad Azani; Yusof, Mohammed Alias; Ismail, Siti Nor Kamariah

    2018-02-01

    Water is the most important resource in times of emergency and during military missions. In addition, if there is a war in a country, sources of clean water are essential for life. But, the safety and cleanliness of the river water for the campers and hikers still uncertain. Usually, polluted and contaminated river water is not safe to be directly consumed by human. However, this problem can be partly resolved by using water filter where the river water can be consumed directly after the filtration process. In respect of that, this study was conducted to design the filter media for personal water purification system. Hence, the objective of this work also is to develop a personal, portable dual purpose handy water filter to provide an easier way to get safe, clean and healthy drinking water for human wherever they go. The water quality of samples collected before and after filtration were analyzed. Water samples were taken from a waterfall near Lestari Block and Lake beside Marine Centre UPNM Campus. The experimental results were analyzed based on the assessment of water quality parameters. Overall, the analysis of the results showed that the water filter was designed with basic mix tabs aqua filter water purification tablets is showing a better result where it achieve the class I of water quality index (WQI). In details, the water sample taken from waterfall near Lestari Block shown the WQI around 93 which is higher than WQI of water sample from Lake near Marine Centre UPNM which is 86, class II A which can be used for external purpose only.

  3. Behavior of Gd-DTPA in simulated bank filtration

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, Peter, E-mail: pemoe@gfz-potsdam.de [Freie Universitaet Berlin, Malteserstr. 74-100, AB Hydrogeologie, 12249 Berlin (Germany)] [Helmholtz Zentrum Potsdam, Deutsches GeoForschungsZentrum, Telegrafenberg, 14473 Potsdam (Germany); Knappe, Andrea [Freie Universitaet Berlin, Malteserstr. 74-100, AB Hydrogeologie, 12249 Berlin (Germany); Dulski, Peter [Helmholtz Zentrum Potsdam, Deutsches GeoForschungsZentrum, Telegrafenberg, 14473 Potsdam (Germany); Pekdeger, Asaf [Freie Universitaet Berlin, Malteserstr. 74-100, AB Hydrogeologie, 12249 Berlin (Germany)

    2011-01-15

    Research highlights: {yields} Gd-DTPA and similar products are common pollutants in surface and groundwater and prove to be a reliable monitor for mixing of groundwater with surface water loaded with effluents from sewage treatment plants. {yields} Within a 30 m column filled with Pleistocene sand Gd-DTPA is reduced by 16% only within one month time by transmetallation. {yields} Artificial bank filtration is not very effective in reducing Gd-DTPA in infiltrating water. - Abstract: The behavior of Gd-DTPA during bank filtration was simulated in a 30 m column filled with Pleistocene sand and flushed by surface water from a lakeside in Berlin, Germany. The surface water is about a 1:1 mixture of river water and effluents from a sewage treatment plant. Throughout 34 days this water was continuously spiked with Gd-DTPA at a level of 60 {mu}g/L. The broad plateau of the Gd-DTPA pulse declined by 15.4% within 34 days by transmetallation. Nine percentage of the total decline is caused by Y and rare earth elements; the remaining part is attributed to Cu{sup 2+} which is the most influential metal in surface water. All other metals also contributing to transmetallation are combined with Cu to Cu equivalents because only the rate constant of transmetallation of Cu{sup 2+} is known. The analytical results of the column effluents prove the pseudo-first-order kinetics of transmetallation based on reversible sorption of metals by pools in the column sediment and disprove biodegradation at noticeable levels. The mass ratio of water to tracer is <10{sup 10}.

  4. MULTILAYER POROUS COMPOSITE FROM WASTE GLASS FOR WATER FILTRATION

    Directory of Open Access Journals (Sweden)

    M. P. Aji

    2015-07-01

    Full Text Available Multilayer porous composite have been produced through the heating process at temperature T=700oC for 2.5 h. Single layered porous composite was made with a varied mass percentage of from PEG polymer  1% to 10%. Double-layered porous composite were made by the arrangement of porosity (4:3%, (4:2% and (3:2%, while the three-layers porous composite have an arrangement (4:3:2%. Performance of multilayer porous composite for water filtration with pollutants of methylene blue 100 ppm was estimated from the absorbance spectrum. Rejection of methylene blue pollutants from single layered porous composite increases when the fraction of PEG polymer tend to be smaller in the matrix. Meanwhile, the double layered porous composite has a degradation of methylene blue pollutants are better than one layer. Triple layered porous composite have good performance for the water filtration where all the pollutants of methylene blue be able to be filtered.   Komposit pori berlapis telah dihasilkan dengan proses pemanasan pada temperatur T=700oC selama 2.5 jam. Komposit pori satu lapis dibuat dengan variasi persen massa polimer PEG 1% hingga 10%. Komposit pori dua lapis dibuat dengan susunan porositas (4:3%, (4:2% dan (3:2%, sedangkan komposit pori tiga lapis memiliki susunan porositas (4:3:2%. Kinerja komposit pori berlapis untuk filter air dengan polutan methylene blue 100 ppm diestimasi dari spektrum absorbansi. Rejeksi polutan methylene blue dari komposit pori satu lapis meningkat saat fraksi polimer PEG cenderung lebih kecil dalam matrik komposit. Sedangkan, komposit pori dua lapis memiliki kemampuan untuk degradasi polutan methylene blue yang lebih baik dari satu lapis. Komposit pori tiga lapis memiliki kinerja yang baik untuk filter air dimana seluruh polutan methylene blue mampu disaring. 

  5. Revealing Rembrandt

    Directory of Open Access Journals (Sweden)

    Andrew J Parker

    2014-04-01

    Full Text Available The power and significance of artwork in shaping human cognition is self-evident. The starting point for our empirical investigations is the view that the task of neuroscience is to integrate itself with other forms of knowledge, rather than to seek to supplant them. In our recent work, we examined a particular aspect of the appreciation of artwork using present-day functional magnetic resonance imaging (fMRI. Our results emphasised the continuity between viewing artwork and other human cognitive activities. We also showed that appreciation of a particular aspect of artwork, namely authenticity, depends upon the co-ordinated activity between the brain regions involved in multiple decision making and those responsible for processing visual information. The findings about brain function probably have no specific consequences for understanding how people respond to the art of Rembrandt in comparison with their response to other artworks. However, the use of images of Rembrandt’s portraits, his most intimate and personal works, clearly had a significant impact upon our viewers, even though they have been spatially confined to the interior of an MRI scanner at the time of viewing. Neuroscientific studies of humans viewing artwork have the capacity to reveal the diversity of human cognitive responses that may be induced by external advice or context as people view artwork in a variety of frameworks and settings.

  6. Sodium Dedecyl Suphate Polyacrilamide Gel Electrophosis of ...

    African Journals Online (AJOL)

    polyacrilamide gel electrophoresis (SDS-PAGE). The isolates were obtained from the faeces of diarrhoeic children with the age range of 0 t 36 months attending paediatric clinic at the Lagos University Teaching Hospital (LUTH) and Obafemi Awolowo ...

  7. Preparation of zirconium molybdate gel generator

    International Nuclear Information System (INIS)

    Charoen, S.; Aungurarat, G.; Laohawilai, S.; Sukontpradit, W.; Jingjit, S.

    1994-01-01

    A procedure for preparation of 99mTc generator based on conversion to zirconium molybdate gel of 99Mo produced by neutron activation was reported. The gel was prepared from zirconium oxychloride solution pH 1.6, ammonium molybdate solution pH 3-5 and mole ratio of Zr:Mo 1:1 which had water content about 7-8%. Small generators containing 1-1.5 g of gel were eluted with average efficiencies of 77% and the activity peak in the first 3 ml of 10 ml of saline solution. The amount of Mo and Zr in eluates were below the acceptance limit. The gel generators of activity about 100 mCi were prepared and had the good performance in elutability and stability

  8. Buckling of paramagnetic chains in soft gels

    Science.gov (United States)

    Huang, Shilin; Pessot, Giorgio; Cremer, Peet; Weeber, Rudolf; Holm, Christian; Nowak, Johannes; Odenbach, Stefan; Menzel, Andreas M.; Auernhammer, Günter K.

    We study the magneto-elastic coupling behavior of paramagnetic chains in soft polymer gels exposed to external magnetic fields. To this end, a laser scanning confocal microscope is used to observe the morphology of the paramagnetic chains together with the deformation field of the surrounding gel network. The paramagnetic chains in soft polymer gels show rich morphological shape changes under oblique magnetic fields, in particular a pronounced buckling deformation. The details of the resulting morphological shapes depend on the length of the chain, the strength of the external magnetic field, and the modulus of the gel. Based on the observation that the magnetic chains are strongly coupled to the surrounding polymer network, a simplified model is developed to describe their buckling behavior. A coarse-grained molecular dynamics simulation model featuring an increased matrix stiffness on the surfaces of the particles leads to morphologies in agreement with the experimentally observed buckling effects.

  9. K-Basin gel formation studies

    International Nuclear Information System (INIS)

    Beck, M.A.

    1998-01-01

    A key part of the proposed waste treatment for K Basin sludge is the elimination of reactive uranium metal by dissolution in nitric acid (Fkirnent, 1998). It has been found (Delegard, 1998a) that upon nitric acid dissolution of the sludge, a gel sometimes forms. Gels are known to sometimes impair solid/liquid separation and/or material transfer. The purpose of the work reported here is to determine the cause(s) of the gel formation and to determine operating parameters for the sludge dissolution that avoid formation of gel. This work and related work were planned in (Fkunent, 1998), (Jewett, 1998) and (Beck, 1998a). This report describes the results of the tests in (Beck, 1998a) with non-radioactive surrogates

  10. Formulation of Bioadhesive Carbomer Gel Incorporating Drug ...

    African Journals Online (AJOL)

    incorporated into carbomer gel and evaluated for drug release. Results: ... localized delivery system for the treatment inflammation and infection in periodontal pockets. ..... loaded with diclofenac sodium for intra- articular administration. J Drug ...

  11. Structure of gels layers with cells

    Science.gov (United States)

    Pokusaev, B. G.; Karlov, S. P.; Vyazmin, A. V.; Nekrasov, D. A.; Zakharov, N. S.; Khramtsov, D. P.; Skladnev, D. A.; Tyupa, D. V.

    2017-11-01

    The structure of two-layer agarose gels containing yeast cells is investigated experimentally by spectrometry, to shed a light on the theoretical foundations for the development of bioreactors by the method of 3D bioprinting. Due to division, cells overcome the layer of the dispersion phase separating successively applied layers of the agarose gel. However a gel layer of 100 μm thick with a high concentration of silver nanoparticles completely excludes the infiltration of yeast cells through it. A special sort of agarose is suggested where the concentration of silver nanoparticles formed by cells from salt of silver can serve as an indicator of the state of the yeast cells in the volume of the gel.

  12. Thixotropic corrosive gels for nuclear decontamination

    International Nuclear Information System (INIS)

    Bargues, St.

    1998-01-01

    The aim of this thesis was the development of corrosive gels for metallic surface decontamination. These gels formulation, based on a powerful oxidant (the cerium IV), the nitric acid, a mineral charge (silica) and a non ionic surface-active, has been developed according to the specific constraints of the nuclear industry. The objective was to prepare thixotropic gels becoming liquid after shacking to allow an easy pulverization and coming again solid to permit a perfect adhesion on the metallic surface. This rheological study of the gels has been completed by an evaluation of their corrosive properties. The last part of the work presents an industrial utilization during two years. (A.L.B.)

  13. Sol-gel antireflective coating on plastics

    Science.gov (United States)

    Ashley, Carol S.; Reed, Scott T.

    1990-01-01

    An antireflection film made from a reliquified sol-gel hydrolyzation, condensation polymeric reaction product of a silicon, alkoxides and/or metal alkoxides, or mixtures thereof. The film is particularly useful for coating plastics.

  14. Coordination Polymer Gels by Electron Beam

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Ha; Cho, Young Je; Jung, Jong Hwa [Gyeongsang National Univ., Jinju (Korea, Republic of)

    2011-07-01

    Hydrogenation of a pyridine derivative possessing tetrazole moieties as end groups, without long alkyl chain groups, results in the formation of a Mg(NO{sub 3}){sub 2} coordination polymer gel. The polymer exhibits a strong fluorescence enhancement upon gel formation. 1 can also be gloated with a variety of magnesium anions such as SO{sub 4}{sup 2-}, NO{sub 3}{sup -}, Cl{sup -}, Br{sup -} and I{sup -}, indicating that the coordination polymer gel formation of 1 does not strongly depends on anions. The Seam and ABM images of Mg{sup 2+} coordination polymer gel 1 display a flabbier network with several micrometers long, widths in the range 60-70 nm and thicknesses of about 3 nm. In addition, photophysical studies show that the hydrogel exhibits a typical {pi}-{pi} transition and gives rise to high fluorescence behavior. The coordination polymer hydrogel exhibits viscoelastic behavior as evidenced from the rheological studies.

  15. Maize Arabinoxylan Gels as Protein Delivery Matrices

    Directory of Open Access Journals (Sweden)

    Ana Luisa Martínez-López

    2009-04-01

    Full Text Available The laccase induced gelation of maize bran arabinoxylans at 2.5% (w/v in the presence of insulin or β-lactoglobulin at 0.1% (w/v was investigated. Insulin and β-lacto-globulin did not modify either the gel elasticity (9 Pa or the cross-links content (0.03 and 0.015 mg di- and triferulic acids/mg arabinoxylan, respectively. The protein release capability of the gel was also investigated. The rate of protein release from gels was dependent on the protein molecular weight. The apparent diffusion coefficient was 0.99 × 10-7 and 0.79 × 10-7 cm2/s for insulin (5 kDa and β-lactoglobulin (18 kDa, respectively. The results suggest that maize bran arabinoxylan gels can be potential candidates for the controlled release of proteins.

  16. Oxygen-17 relaxation in aqueous agarose gels

    International Nuclear Information System (INIS)

    Ablett, S.; Lillford, P.J.

    1977-01-01

    Nuclear magnetic relaxation of oxygen-17 in H 2 17 O enriched agarose gels shows that existing explanations of water behaviour are oversimplified. Satisfactory models must include at least three proton phases, two of which involve water molecules. (Auth.)

  17. Measurement of single-kidney glomerular filtration function from magnetic resonance perfusion renography

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Meiying; Cheng, Yingsheng [Department of Radiology, Shanghai Jiao Tong University Affiliated Sixth People' s Hospital, Shanghai 200233 (China); Zhao, Binghui, E-mail: binghuizhao@163.com [Department of Radiology, Shanghai Tenth People' s Hospital, Tongji University, Shanghai 200072 (China)

    2015-08-15

    Highlights: • MRPR monitors the transit of contrast material through nephron. • MRPR could reveal renal physiological characteristics in quality and quantity. • This review outlines the basics and future challenges of DCE MRPR. - Abstract: Glomerular filtration rate (GFR) describes the flow rate of filtered fluid through the kidney, and is considered to be the reference standard in the evaluation of renal function. There are many ways to test the GFR clinically, such as serum creatinine concentration, blood urea nitrogen and SPECT renography, however, they’re all not a good standard to evaluate the early damage of renal function. In recent years, the improvement of MRI hardware and software makes it possible to reveal physiological characteristics such as renal blood flow or GFR by dynamic contrast enhancement magnetic resonance perfusion renography (DEC MRPR). MRPR is a method used to monitor the transit of contrast material, typically a gadolinium chelate, through the renal cortex, the medulla, and the collecting system. This review outlines the basics of DCE MRPR included acquisition of dynamic MR perfusion imaging, calculation of the contrast concentration from signal intensity and compartment models, and some challenges of MRPR method faced in prospective clinical application.

  18. Irreversible fouling of membrane bioreactors due to formation of a non-biofilm gel layer

    DEFF Research Database (Denmark)

    Poorasgari, Eskandar; Larsen, Poul; Zheng, Xing

    2014-01-01

    Extra-cellular polymeric substances (EPS), known to contribute to fouling in membrane bio-reactors (MBRs), are generally divided into bound and free EPS. The free EPS are able to form a gel layer on the membrane active surface. The mechanisms involved in formation of such layer and its effects...... on performance of the MBR membranes were studied. The free EPS, extracted by centrifugation and microfiltration, contained a significant amount of humic-like substances. Under static contact to the membrane, adsorption of humic-like substances to the membrane occurred and could be explained by conventional...... adsorption kinetics. Due to static adsorption, surface roughness of the membrane declined significantly, indicating that adsorbed matters to the membranefilled the cavities of the membrane surface. Filtration of the free EPS caused 50% waterflux decline. The fouling resistance linearly increased...

  19. Organic carbon aerogels from the sol-gel polymerization of phenolic-furfural mixtures

    Science.gov (United States)

    Pekala, R.W.

    1998-04-28

    The sol-gel polymerization of a phenolic-furfural mixture in dilute solution leads to a highly cross-linked network that can be supercritically dried to form a high surface area foam. These porous materials have cell/pore sizes {<=}1000 {angstrom}, and although they are dark brown in color, they can be classified as a new type of aerogel. The phenolic-furfural aerogel can be pyrolyzed in an inert atmosphere at 1050 C to produce carbon aerogels. This new aerogel may be used for thermal insulation, chromatographic packing, water filtration, ion-exchange, and carbon electrodes for energy storage devices, such as batteries and double-layer capacitors. 8 figs.

  20. Organic aerogels from the sol-gel polymerization of phenolic-furfural mixtures

    Science.gov (United States)

    Pekala, R.W.

    1995-12-19

    The sol-gel polymerization of a phenolic-furfural mixture in dilute solution leads to a highly cross-linked network that can be supercritically dried to form a high surface area foam. These porous materials have cell/pore sizes{<=}1000{angstrom}, and although they are dark brown in color, they can be classified as a new type of aerogel. The phenolic-furfural aerogel can be pyrolyzed in an inert atmosphere at 1050 C to produce carbon aerogels. This new aerogel may be used for thermal insulation, chromatographic packing, water filtration, ion-exchange, and carbon electrodes for energy storage devices, such as batteries and double-layer capacitors. 8 figs.