Selective separation of Eu3+ using polymer-enhanced ultrafiltration

International Nuclear Information System (INIS)

Norton, M.V.

1994-03-01

A process to selectively remove 241 Am from liquid radioactive waste was investigated as an actinide separation method applicable to Hanford and other waste sites. The experimental procedures involved removal of Eu, a nonradioactive surrogate for Am, from aqueous solutions at pH 5 using organic polymers in conjunction with ultrafiltration. Commercially available polyacrylic acid (60,000 MW) and Pacific Northwest Laboratory's (PNL) synthesized E3 copolymer (∼10,000 MW) were tested. Test solutions containing 10 μg/mL of Eu were dosed vath each polymer at various concentrations in order to bind Eu (i.e., by complexation and/or cation exchange) for subsequent rejection by an ultrafiltration coupon. Test solutions were filtered with and without polymer to determine if enhanced Eu separation could be achieved from polymer treatment. Both polymers significantly increased Eu removal. Optimum concentrations were 20 μg/mL of polyacrylic acid and 100 μg/mL of E3 for 100% Eu rejection by the Amicon PM10 membrane at 55 psi. In addition to enhancement of removal, the polymers selectively bound Eu over Na, suggesting that selective separation of Eu was possible. This suggests that polymer-enhanced ultrafiltration is a potential process for separation of 241 Am from Hanford tank waste, further investigation of binding agents and membranes effective under very alkaline and high ionic strength is warranted. This process also has potential applications for selective separation of toxic metals from industrial process streams

Protein bioseparation using ultrafiltration: theory, applications and new developments

National Research Council Canada - National Science Library

Ghosh, Raja

2003-01-01

... membrane-based separation process. This book discusses how ultrafiltration could be used for protein bioseparation. There are several good books on protein bioseparation and indeed several others on ultrafiltration. However, there are relatively fewer books dealing specifically with protein bioseparation using ultrafiltration, in spite of this being an a...

The Effect of Cellulose Acetate Concentration from Coconut Nira on Ultrafiltration Membrane Characters

Science.gov (United States)

Vaulina, E.; Widyaningsih, S.; Kartika, D.; Romdoni, M. P.

2018-04-01

Cellulose acetate is one of material in produce ultrafiltration membrane. Many efforts have been done to produce cellulose acetate from natural product to replace commercial one. In this research, ultrafiltration membrane has been produced from coconut flower water (nira). Ultrafiltration membrane is widely used in separation processes. This research aims to determine the characteristics of ultrafiltration membrane at a various concentration of cellulose acetate. The ultrafiltration membrane is conducted by phase inversion method at various concentration of cellulose acetate. The cellulose acetate concentration was 20%, 23% and 25% (w/w) with formamide as additives. The results showed that the greater the concentration of cellulose acetate, the smaller the flux value. The highest flux was a membrane with 20% cellulose acetate concentration with water flux value 55.34 L/(m2. h). But the greater the concentration of cellulose acetate the greater the rejection. The highest rejection value was on a membrane with 25% cellulose acetate concentration of 82.82%. While from the tensile strength test and the pore size analysis, the greater the cellulose acetate concentration the greater the tensile strength and the smaller the pore size

Adsorption of amylase enzyme on ultrafiltration membranes

DEFF Research Database (Denmark)

Beier, Søren; Enevoldsen, Ann Dorrit; Kontogeorgis, Georgios

2007-01-01

A method to measure the static adsorption on membrane surfaces has been developed and described. The static adsorption of an amylase-F has been measured on two different ultrafiltration membranes, both with a cut-off value of 10 kDa (a PES membrane and the ETNA10PP membrane, which is a surface......-modified PVDF membrane). The adsorption follows the Langmuir adsorption theory. Thus, the static adsorption consists of monolayer coverage. The static adsorption is expressed both as a permeability drop and an adsorption resistance. From the adsorption isotherms the maximum static permeability drops...... and the maximum static adsorption resistances are determined. The maximum static permeability drop for the hydrophobic PES membrane is 75 % and the maximum static adsorption resistance is 0.014 m2hbar/L. The maximum static permeability drop for the hydrophilic surface-modified PVDF membrane (ETNA10PP) is 23...

Oily bilge water treatment with a tubular ultrafiltration system

Energy Technology Data Exchange (ETDEWEB)

Harris, L.R.; Jackson, D.F.; Schatzberg, P.

1976-11-01

The Navy has been developing various oil pollution abatement systems. One potential process for the separation of oil in bilge water is ultrafiltration, a pressure-driven membrane process which can separate, concentrate, and fractionate macromolecular solutes and suspended species from water. A tubular ultrafiltration system using cellulosic and noncellulosic membranes was tested with bilge oil obtained from a patrol craft. Tests were also conducted with tap water, river water, a turbine lubricating oil, and a fuel oil, alone and in combination with a nonionic detergent. The addition of the detergent was observed to result in a steeper flux decline than when any of the fluids were evaluated alone. Both membrane types produced a permeate with an oil content generally less than 15 mg/l. Although the noncellulosic membranes exhibited higher flux rates than the cellulosic membranes, only the former could be restored by a cleaning operation to its initial water flux after experiencing a decline in flux. A cumulative irreversible flux decline was exhibited by the cellulosic membrane. Cleaning operations, some of which were time-consuming, consisted of flushing the membrane with ultrafiltrate, distilled water, tap water, or the manufacturer's enzyme-detergent formulation. Only the last of these, when employed at elevated temperature (125/sup 0/F), restored the initial water flux of the noncellulosic membrane.

SURVEY REGARDING THE ULTRAFILTRATION OF PROTEINES THROUGH MEMBRANE BASED PROCEDURES

Directory of Open Access Journals (Sweden)

CAMELIA HODOSAN

2008-05-01

Full Text Available This work is based on examples that emphasize the complexity of the proteins ultrafiltration process, pointing out the first 10-15 minutes of ultrafiltration. The knowledgement of the factors that influence the separation through ultrafiltration of proteins will allow to choose the right type of membrane, the frequent use of the same membrane and the operation in mechanical and chemical conditions adequate to the ultrafiltration system, when it is separated a protein with certain molecular weight.

Development of ultrafiltration and inorganic adsorbents: January--March 1977

International Nuclear Information System (INIS)

Koenst, J.W. Jr.

1977-01-01

Ultrafiltration media with and without the assistance of bone char filters were evaluated to determine their effectiveness in removing radionuclides from contaminated solutions. Precipitants, resin, adsorbents, and inorganic adsorbents were studied to determine their effectiveness in decontaminating solutions. A study of the effects of radiation on ultrafiltration media was initiated. An ultrafiltration media pilot plant was ordered and is being installed

Pilot-scale ultrafiltration testing for the F and H area effluent treatment facility

International Nuclear Information System (INIS)

Kessler, J.L.

1984-01-01

An F and H Area Effluent Treatment Facility (F/H ETF) is being designed to treat low activity aqueous effluents which are produced from F and H Area daily operations. The treatment scheme for the F/H ETF will include pretreatment (pH adjustment and filtration) followed by Reverse Osmosis and/or Ion Exchange to remove dissolved species. Several alternative treatment processes are being considered for the F/H ETF. One of the alternatives in the pretreatment step is tubular Ultrafiltration (UF), using a dynamically formed zirconium oxide membrane supported on a porous stainless steel backing. Pilot-scale testing with a single membrane module (13 ft 2 area) and 200-Area effluent simulant has demonstrated that UF is a viable filtration option for the F/H ETF. UF testing at TNX has defined the operating conditions necessary for extended operation and also demonstrated excellent filtration performance (filtrate SDI 2 /day) flux and will provide excellent pretreatment for both reverse osmosis and ion exchange. 2 refs

Ultrafiltration of pegylated proteins

Science.gov (United States)

Molek, Jessica R.

There is considerable clinical interest in the use of "second-generation" therapeutics produced by conjugation of a native protein with various polymers including polyethylene glycol (PEG). PEG--protein conjugates, so-called PEGylated proteins, can exhibit enhanced stability, half-life, and bioavailability. One of the challenges in the commercial production of PEGylated proteins is the purification required to remove unreacted polymer, native protein, and in many cases PEGylated proteins with nonoptimal degrees of conjugation. The overall objective of this thesis was to examine the use of ultrafiltration for the purification of PEGylated proteins. This included: (1) analysis of size-based separation of PEGylated proteins using conventional ultrafiltration membranes, (2) use of electrically-charged membranes to exploit differences in electrostatic interactions, and (3) examination of the effects of PEGylation on protein fouling. The experimental results were analyzed using appropriate theoretical models, with the underlying physical properties of the PEGylated proteins evaluated using size exclusion chromatography, capillary electrophoresis, dynamic light scattering, and reverse phase chromatography. PEGylated proteins were produced by covalent attachment of activated PEG to a protein via primary amines on the lysine residues. A simple model was developed for the reaction kinetics, which was used to explore the effect of reaction conditions and mode of operation on the distribution of PEGylated products. The effective size of the PEGylated proteins was evaluated using size exclusion chromatography, with appropriate correlations developed for the size in terms of the molecular weight of the native protein and attached PEG. The electrophoretic mobility of the PEGylated proteins were evaluated by capillary electrophoresis with the data in good agreement with a simple model accounting for the increase in protein size and the reduction in the number of protonated amine

Preparation of PES ultrafiltration membranes with natural amino acids based zwitterionic antifouling surfaces

International Nuclear Information System (INIS)

Xu, Chen; Liu, Xiaojiu; Xie, Binbin; Yao, Chen; Hu, Wenhan; Li, Yi; Li, Xinsong

2016-01-01

related to protein with opposite electric charges. Furthermore, the ultrafiltration performance of the zwitterionic PES membranes was evaluated. The results showed that the modified membranes possessed of enhanced pure water flux, relative flux recovery and mildly lower rejection. The Darcy’s Law analysis illustrated that the acidic amino acid grafted PES membranes had much lower permeation resistance due to hydrophilicty increasing and protein adsorption decreasing. Therefore, grafting natural amino acids onto PES ultrafiltration membrane provides an effective approach to combat biofouling in separation fields.

Preparation of PES ultrafiltration membranes with natural amino acids based zwitterionic antifouling surfaces

Energy Technology Data Exchange (ETDEWEB)

Xu, Chen; Liu, Xiaojiu; Xie, Binbin; Yao, Chen [School of Chemistry and Chemical Engineering, Southeast University, Nanjing, 211189 (China); Hu, Wenhan; Li, Yi [Suzhou Faith & Hope Membrane Technology Co., Ltd., Suzhou, 215000 (China); Li, Xinsong, E-mail: lixs@seu.edu.cn [School of Chemistry and Chemical Engineering, Southeast University, Nanjing, 211189 (China)

2016-11-01

related to protein with opposite electric charges. Furthermore, the ultrafiltration performance of the zwitterionic PES membranes was evaluated. The results showed that the modified membranes possessed of enhanced pure water flux, relative flux recovery and mildly lower rejection. The Darcy’s Law analysis illustrated that the acidic amino acid grafted PES membranes had much lower permeation resistance due to hydrophilicty increasing and protein adsorption decreasing. Therefore, grafting natural amino acids onto PES ultrafiltration membrane provides an effective approach to combat biofouling in separation fields.

Removal of copper ions from aqueous solutions by means of micellar-enhanced ultrafiltration

Directory of Open Access Journals (Sweden)

Kowalska Izabela

2017-01-01

Full Text Available The aim of the study was to assess the usefulness of micellar–enhanced ultrafiltration (MEUF for removal of copper ions from water solutions in comparison with classic ultrafiltration process. The tests were conducted in a semi–pilot membrane installation with the use of ultrafiltration module KOCH/ROMICON® at a transmembrane pressure of 0.05 MPa. The effect of concentration of copper ions on ultrafiltration process efficiency was investigated. The second part of the tests concerned the removal of copper ions by MEUF under wide range of anionic surfactant concentration (0.25, 1, and 5 CMC (critical micelle concentration. Concentration of copper ions in model solutions was equal to 5, 20, and 50 mg Cu/L. Furthermore, the effect of surfactant leakage to the permeate side during filtration was evaluated. Conducted experiments confirmed effectiveness of MEUF in copper ions removal. For the highest copper concentration in the feed (i.e. 50 mg/L, the average concentration of copper ions in the permeate ranged from 1.2–4.7 mg Cu/L depending on surfactant concentration. During filtration experiments, UF module exhibited stable transport properties for model solutions containing copper. For the highest concentration of metal, the decrease of permeate flux did not exceed 11% after 60 minutes of filtration. In the presence of the surfactant, a slight deterioration of transport properties was observed.

Radiocarbon dating of VIRI bone samples using ultrafiltration

Energy Technology Data Exchange (ETDEWEB)

Minami, Masayo, E-mail: minami@nendai.nagoya-u.ac.jp [Center for Chronological Research, Nagoya University, Nagoya 464-8602 (Japan); Yamazaki, Kana [Faculty of Science, Nagoya University, Nagoya 464-8602 (Japan); Omori, Takayuki [University Museum, University of Tokyo, Tokyo 113-0033 (Japan); Nakamura, Toshio [Center for Chronological Research, Nagoya University, Nagoya 464-8602 (Japan)

2013-01-15

Ultrafiltration can effectively remove low-molecular-weight (LMW) contaminants from bone gelatin to extract high-molecular-weight (HMW) proteins that are derived from original bone collagen, though it cannot remove HMW collagen crosslinked with humic acids. Therefore, ultrafiltration is often used to obtain more accurate {sup 14}C dates of bones. However, ultrafiltration may introduce new contaminants to bone gelatins, mainly from ultrafilters used. To study the effects of ultrafiltration on {sup 14}C age, we analyzed the C/N ratio, {delta}{sup 13}C{sub PDB} and {delta}{sup 15}N{sub AIR} values, and {sup 14}C ages of acid-soluble bone collagen obtained by decalcification, gelatin extracted from acid-insoluble bone collagen, and the HMW gelatin and LMW fractions produced during ultrafiltration of the extracted gelatin. Bone samples from the Fifth International Radiocarbon Intercomparison (VIRI) were used: VIRI-E (mammoth), -F (horse), -G (human), and -I (whale). In this study, carbon and nitrogen content and gelatin yields were used to evaluate collagen preservation in the VIRI bone samples. Radiocarbon ages, {delta}{sup 13}C{sub PDB} and {delta}{sup 15}N{sub AIR} values of unfiltered and HMW gelatins were obtained and compared with the published consensus values. The LMW fraction was found to exhibit different values from those of the other fractions, indicating the possible presence of extraneous contamination. The Vivaspin Trade-Mark-Sign 6 ultrafilters used in this study were analyzed and radiocarbon dated both before and after cleaning. We present evidence to suggest that LMW fraction contaminants could be derived from the ultrafilters rather than humic substances. Excessively long ultrafiltration time was suspected to have contaminated the bone samples with material from the ultrafilter, because those samples exhibited older {sup 14}C ages than did those filtered for shorter durations. The results in this study indicate that {sup 14}C ages of unfiltered

An ultrafiltration assay for lysyl oxidase

International Nuclear Information System (INIS)

Shackleton, D.R.; Hulmes, D.J.

1990-01-01

A modification of the original microdistillation assay for lysyl oxidase is described in which Amicon C-10 microconcentrators are used to separate, by ultrafiltration, the 3H-labeled products released from a [4,5-3H]-lysine-labeled elastin substrate. Enzyme activity is determined by scintillation counting of the ultrafiltrate, after subtraction of radioactivity released in the presence of beta-aminopropionitrile, a specific inhibitor of the enzyme. Conditions are described which optimize both the sensitivity and the efficient use of substrate. The assay shows linear inhibition of activity in up to 1 M urea; hence, as the enzyme is normally diluted in the assay, samples in 6 M urea can be assayed directly, without prior dialysis, and corrected for partial inhibition. Comparable results are obtained when enzyme activity is assayed by ultrafiltration or microdistillation. The assay is simple and convenient and, by using disposable containers throughout, it eliminates the need for time-consuming decontamination of radioactive glassware

Ultrafiltration of hemicellulose hydrolysate fermentation broth

Science.gov (United States)

Kresnowati, M. T. A. P.; Desiriani, Ria; Wenten, I. G.

2017-03-01

Hemicelulosic material is often used as the main substrate to obtain high-value products such as xylose. The five carbon sugar, xylose, could be further processed by fermentation to produce xylitol. However, not only the hemicellulose hydrolysate fermentation broth contains xylitol, but also metabolite products, residual substances, biomass and mineral salts. Therefore, in order to obtain the end products, various separation processes are required to separate and purify the desired product from the fermentation broth. One of the most promising downstream processing methods of fermentation broth clarification is ultrafiltration due to its potential for energy saving and higher purity. In addition, ultrafiltration membrane has a high performance in separating inhibitory components in the fermentation broth. This paper assesses the influence of operating conditions; including trans-membrane pressure, velocity, pH of the fermentation broth solutions, and also to the xylitol concentration in the product. The challenges of the ultrafiltration process will be pointed out.

Preparation of ultrafiltration membrane by phase separation coupled with microwave irradiation

Energy Technology Data Exchange (ETDEWEB)

Suryani, Puput Eka [Department of Chemical Engineering, Faculty of Engineering, Diponegoro University Jl. Prof. Soedarto, Semarang 50275, Central Java (Indonesia); Department of Chemical Engineering, Faculty of Engineering, UniversitasMuhammadiyah Surakarta Jl. Jendral Ahmad Yani, Surakarta 57102, Central Java (Indonesia); Purnama, Herry [Department of Chemical Engineering, Faculty of Engineering, UniversitasMuhammadiyah Surakarta Jl. Jendral Ahmad Yani, Surakarta 57102, Central Java (Indonesia); Susanto, Heru, E-mail: heru.susanto@undip.ac.id [Department of Chemical Engineering, Faculty of Engineering, Diponegoro University Jl. Prof. Soedarto, Semarang 50275, Central Java (Indonesia)

2015-12-29

Preparation of low fouling ultrafiltration membrane is still a big challenge in the membrane field. In this paper, polyether sulfone (PES) ultrafiltration membranes were prepared by non-solvent-induced phase separation (NIPS) coupled with microwave irradiation. Polyethylene glycol (PEG) and polyethylene glycol methacrylate (PEGMA) were used as additives to improve membrane hydrophilicity. In this study, the concentration of additive, irradiation time and microwave power was varied. The membranes were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy, while the performances were tested by adsorptive and ultrafiltration fouling experiments. The results show that the irradiation time and irradiation power are very important parameter that influence the membrane characteristic. In addition, type and concentration of additive are other important parameters. The results suggest that microwave irradiation is the most important parameter influencing the membrane characteristic. Both pure water flux and fouling resistance increase with increasing irradiation time, power irradiation, and additive concentration. PES membrane with addition of 10% w/w PEG and irradiated by 130 W microwave power for 180 seconds is the best membrane performance.

A simplified ultrafiltration method for determination of serum free cortisol

International Nuclear Information System (INIS)

MacMahon, W.; Sgoutas, D.

1983-01-01

The authors describe the suitability of the Amicon MPS-1 centrifugal ultrafiltration device and the YMB membrane for measuring free cortisol in serum. The method combines two independent assays: total cortisol and the ultrafiltrate fraction of added [ 3 H]cortisol. The unbound fraction is determined in 0.25-0.30 ml of ultrafiltrate collected from 0.6 to 1 ml of serum that has been equilibrated with [ 3 H]cortisol at 37 0 C for 20 min. The assay is rapid (less than 1 h), practical (no more than 0.6 ml of serum is necessary) and repeatable (CV: 3.8% within-assay and 12.2% in different assays). Error introduced in free cortisol measurement due to dilution effects in dialysis is systematically defined, and the effect of tracer purity on the ultrafiltration method is examined. Dialyzed sera from normal men and women, from patients with Cushing's disease and adrenal insufficiency, and from pregnant women gave ultrafiltration results that accurately duplicated those obtained by previous dialysis. (Auth.)

Decontamination by ultrafiltration of low radioactivity waste water from fuel element fabrication

International Nuclear Information System (INIS)

Muller, H.M.

1984-01-01

It could be demonstrated that waste waters which contain uranium in a filterable form, such as laundry and floor-cleaning waste, can be sufficiently decontaminated by means of ultra-filtration. In the case of process waste solutions, which contain uranium in a dissolved form, high decontamination factors could be achieved by means of flocculation or coprecipitation. The following methods were tested: - flocculation with Fe (OH) 3 , - coprecipitation with CaHPO 4 , - precipitation with K 4 (Fe(CN) 6 ). The phosphate precipitation, whereby the uranium is probably coprecipitated as Ca(UO 2 ) 2 (PO 4 ) 2 , was found to be the most reliable method. Difficulties were encountered when complex-forming anions, notably carbonate, oxalate and fluoride were present. These necessitate specific pretreatment steps. Whether ultrafiltration then still remains an economical option must be judged in each individual case. The application of the methods so far developed on combined waste streams remains an object for further research. In combination with a phosphate precipitation, ultrafiltration is a suitable method for the decontamination of low-activity, uranium-contaminated waste waters

Evaluation of Ultrafiltration Performance for Phospholipid Separation

Science.gov (United States)

Aryanti, N.; Wardhani, D. H.; Maulana, Z. S.; Roberto, D.

2017-11-01

Ultrafiltration membrane for degumming of crude palm oil has been applied as an alternative method since the membrane process required less procedure than the conventional degumming. This research focused on the examination of ultrafiltration performance for phospholipid separation from model crude palm oil degumming. Specifically, profile flux and rejection, as well as blocking mechanism, were investigated. Feed consisting of Refined Crude Palm Oil - Isopropanol - Lecithin mixtures were represented as crude palm oil degumming. Lecithin was denoted a phospholipid component, and the concentrations of lecithin in feed were varied to 0.1%, 0.2%, and 0.3%. The concentration of phospholipid was determined as phosphor content. At the concentration of lecithin in feed representing phospholipid concentration of 8,45 mg/kg, 8,45 mg/kg, 24,87 mg/kg and 57,58 mg/kg, respectively. Flux profiles confirmed that there was a flux decline during filtration. In addition, the lecithin concentrations do not significantly effect on further flux decline. Rejection characteristic and phospholipid concentration in the permeate showed that the phospholipid rejections by ultrafiltration were in the range of 23-79,5% representing permeate’s phospholipid concentration of 1,73 - 44,25 mg/kg. Evaluation of fouling mechanism by Hermia’s blocking model confirmed that the standard blocking is the dominant mechanism in the ultrafiltration of lecithin mixture.

Ultrafiltrative deinking of flexographic ONP : the role of surfactants

Science.gov (United States)

Bradley H. Upton; Gopal A. Krishnagopalan; Said Abubakr

1999-01-01

Ultrafiltration is a potentially viable method of removing finely dispersed flexographic pigments from the deinking water loop. This work examines the effects of surface-active materials on ultrafiltration efficiency. A logarithmic relationship between permeate flax and pigment concentration was demonstrated at ink concentrations above 0.4%, permeation rates becoming...

Ultrafiltration technology with a ceramic membrane for reactive dye removal: optimization of membrane performance.

Science.gov (United States)

Alventosa-deLara, E; Barredo-Damas, S; Alcaina-Miranda, M I; Iborra-Clar, M I

2012-03-30

An ultrafiltration (UF) ceramic membrane was used to decolorize Reactive Black 5 (RB5) solutions at different dye concentrations (50 and 500 mg/L). Transmembrane pressure (TMP) and cross-flow velocity (CFV) were modified to study their influence on initial and steady-state permeate flux (J(p)) and dye rejection (R). Generally, J(p) increased with higher TMP and CFV and lower feed concentration, up to a maximum steady-state J(p) of 266.81 L/(m(2)h), obtained at 3 bar, 3m/s and 50mg/L. However, there was a TMP value (which changed depending on operating CFV and concentration) beyond which slight or no further increase in steady-state J(p) was observed. Similarly, the higher the CFV was, the more slightly the steady-state J(p) increased. Furthermore, the effectiveness of ultrafiltration treatment was evaluated through dye rejection coefficient. The results showed significant dye removals, regardless of the tested conditions, with steady-state R higher than 79.8% for the 50mg/L runs and around 73.2% for the 500 mg/L runs. Finally response surface methodology (RSM) was used to optimize membrane performance. At 50mg/L, a TMP of 4 bar and a CFV of 2.53 m/s were found to be the conditions giving the highest steady-state J(p), 255.86 L/(m(2)h), and the highest R, 95.2% simultaneously. Copyright © 2012 Elsevier B.V. All rights reserved.

Role of modified ultrfiltration in adult cardic surgery: a prospective randomized control trial

International Nuclear Information System (INIS)

Naveed, D.; Khan, R.A.; Malik, A.; Shah, S.Z.A.; Ullah, I.; Hussain, A.

2016-01-01

Background: Cardiopulmonary bypass (CPB) is associated with morbidity and mortality. To reduce its adverse effect modified ultrafiltration is being increasingly employed. This study is planned to evaluate the benefits of modified ultrafiltration (MUF) in adult cardiac surgery. Methods: Eighty consecutive patients presenting to adult cardiac surgery as elective case were enrolled. These patients were randomly divided in to two groups. MUF group which received modified ultrafiltration after separation from CPB and control group which did not receive modified ultrafiltration. Postoperative mediastinal and chest drainage in 24 hrs, blood products requirement, reopening, ICU stay, and mortality in 30 days were recorded. These variables were compared between MUF group and control group. Results: Forty patients were randomized to control group and 40 in MUF group. Mean age was 51.15±8.90 in control group as compared to 46.95±13.24 MUF group (p=0.1). Out of 40 patients in control group 7 (17.5 percentage) were female while 11 (27.5 percentage) out of total 40 were female in MUF group. (p=.284). Mean CBP time was 120.62±20.97 in control group versus 117.37±38.78 in MUF group (p=0.64). Post-operative drain output ranged from 330 ml to 1300 ml in control group and 300 ml to 780 ml in MUF group. Mean postoperative drain output 554.25±192.57 in control group versus 439.22±89.59 in MUF group (p=.001). Three (7.5 percentage) out of 40 patients required re-exploration in control group versus 1 (2.5 percentage) in MUF group. (p=.305). Mean ICU stay was 52.80±22.37 hours in control group versus 45.30±21.82 hours in MUF group (p=0.133). Three (7.5 percentage) out of 40 patients died in control group versus 1 (2.5 percentage) in MUF group. (p=0.305). Conclusion: Use of modified ultrafiltration is associated with low postoperative bleeding less requirements of blood and blood products. (author)

Reexamining ultrafiltration and solute transport in groundwater

Science.gov (United States)

Neuzil, C. E.; Person, Mark

2017-06-01

Geologic ultrafiltration—slowing of solutes with respect to flowing groundwater—poses a conundrum: it is consistently observed experimentally in clay-rich lithologies, but has been difficult to identify in subsurface data. Resolving this could be important for clarifying clay and shale transport properties at large scales as well as interpreting solute and isotope patterns for applications ranging from nuclear waste repository siting to understanding fluid transport in tectonically active environments. Simulations of one-dimensional NaCl transport across ultrafiltering clay membrane strata constrained by emerging data on geologic membrane properties showed different ultrafiltration effects than have often been envisioned. In relatively high-permeability advection-dominated regimes, salinity increases occurred mostly within membrane units while their effluent salinity initially fell and then rose to match solute delivery. In relatively low-permeability diffusion-dominated regimes, salinity peaked at the membrane upstream boundary and effluent salinity remained low. In both scenarios, however, only modest salinity changes (up to ˜3 g L-1) occurred because of self-limiting tendencies; membrane efficiency declines as salinity rises, and although sediment compaction increases efficiency, it is also decreases permeability and allows diffusive transport to dominate. It appears difficult for ultrafiltration to generate brines as speculated, but widespread and less extreme ultrafiltration effects in the subsurface could be unrecognized. Conditions needed for ultrafiltration are present in settings that include topographically-driven flow systems, confined aquifer systems subjected to injection or withdrawal, compacting basins, and accretionary complexes.

Role of Peritoneal Ultrafiltration in Heart Failure Treatment

Directory of Open Access Journals (Sweden)

Tuba Elif Şenel

2017-09-01

Full Text Available Cardiorenal syndrome (CRS is a general term that can reflect different clinical conditions in which cardiac and renal dysfunctions coexist. The main pathogenetic mechanisms playing a role in heart failure (HF and CRS are neurohumoral adaptation, right ventricular dilatation and dysfunction and systemic inflammation. Persistence of these factors cause focal and segmental glomerulosclerosis, and tubulointerstitial fibrosis in the renal parenchyma. Diuretics, beta blockers, renin-angiotensin-aldosterone system inhibitors, and vasodilators are the main medical treatments besides conventional approach, such as salt and water restriction and quitting smoking, in HF treatment. Diuretic resistance is the main problem emerging during diuretic treatments. Two renal replacement treatments have become prominent for removal of excess fluids via ultrafiltration in HF patients with diuretic resistance extracorporeal ultrafiltration with hemodialysis and peritoneal dialysis (PD. Herein, the role of these two ultrafiltration modalities, especially peritoneal ultrafiltration (PUF in the treatment of HF is discussed. The main studies and advantages of PUF in HF treatment were discussed. Moreover, effects of PD on glomerular filtration rate, hospitalization and mortality were investigated. In conclusion, PD is an alternative cheap, practical and convenient therapy in reducing cardiac volume burden in HF patients who do not respond well to standard treatments and/or require frequent hospitalization.

Ultrafiltration Membrane Fouling and the Effect of Ion Exchange Resins

KAUST Repository

Jamaly, Sanaa

2011-12-01

Membrane fouling is a challenging process for the ultrafiltration membrane during wastewater treatment. This research paper determines the organic character of foulants of different kinds of wastewater before and after adding some ion exchange resins. Two advanced organic characterization methods are compared in terms of concentration of dissolved organic carbons: The liquid chromatography with organic carbon (LC-OCD) and Shimadzu total organic carbon (TOC). In this study, two secondary wastewater effluents were treated using ultrafiltration membrane. To reduce fouling, pretreatment using some adsorbents were used in the study. Six ion exchange resins out of twenty were chosen to compare the effect of adsorbents on fouling membrane. Based on the percent of dissolved organic carbon’s removal, three adsorbents were determined to be the most efficient (DOWEX Marathon 11 anion exchange resin, DOWEX Optipore SD2 polymeric adsorbent, and DOWEX PSR2 anion exchange), and three other ones were determined to the least efficient (DOWEX Marathon A2 anion exchange resin, DOWEX SAR anion exchange resin, and DOWEX Optipore L493 polymeric adsorbent). Organic characterization for feed, permeate, and backwash samples were tested using LC-OCD and TOC to better understand the characteristics of foulants to prevent ultrafiltration membrane fouling. The results suggested that the polymeric ion exchange resin, DOWEX SD2, reduced fouling potential for both treated wastewaters. All the six ion exchange resins removed more humic fraction than other organic fractions in different percent, so this fraction is not the main for cause for UF membrane fouling. The fouling of colloids was tested before and after adding calcium. There is a severe fouling after adding Ca2+ to effluent colloids.

On the use of ultrafiltration membranes in oily water separators

Energy Technology Data Exchange (ETDEWEB)

Tremblay, A.Y.; Nottegar, M. [Ottawa Univ., ON (Canada). Dept. of Chemical Engineering; Veinot, D.E. [Defence Research Establishment Atlantic, Halifax, NS (Canada)

2000-07-01

Laboratory studies were conducted on the use of ultrafiltration membranes for oil water purification from ships bilges. Bilge water is a complex and highly variable mixture of several components such as seawater, lubricating oil, greases, marine diesel fuel, hydraulic oil, detergents, metal oxides, corrosion inhibitors, asbestos and other wastes. This laboratory study examined the performance of ultrafiltration membranes when separating oily waste water of similar composition to that of bilge water. Ultrafiltration membranes are nanoporous materials produced from ceramic, polymeric or metallic substrates. The ability of the membrane to retain macromolecules, colloids, sub-micron particles and oil emulsions depends on the size of the nanopores. The best results in this study occurred when upper and lower bounds on the membrane pore size were found to exist. It was determined that ultrafiltration is a viable separation process for the treatment of bilge water for compliance with overboard discharge regulations. 7 refs., 1 tab., 3 figs.

Water hammer reduces fouling during natural water ultrafiltration.

Science.gov (United States)

Broens, F; Menne, D; Pothof, I; Blankert, B; Roesink, H D W; Futselaar, H; Lammertink, R G H; Wessling, M

2012-03-15

Today's ultrafiltration processes use permeate flow reversal to remove fouling deposits on the feed side of ultrafiltration membranes. We report an as effective method: the opening and rapid closing of a valve on the permeate side of an ultrafiltration module. The sudden valve closure generates pressure fluctuations due to fluid inertia and is commonly known as "water hammer". Surface water was filtrated in hollow fiber ultrafiltration membranes with a small (5%) crossflow. Filtration experiments above sustainable flux levels (>125 l (m2h)(-1)) show that a periodic closure of a valve on the permeate side improves filtration performance as a consequence of reduced fouling. It was shown that this effect depends on flux and actuation frequency of the valve. The time period that the valve was closed proved to have no effect on filtration performance. The pressure fluctuations generated by the sudden stop in fluid motion due to the valve closure are responsible for the effect of fouling reduction. High frequency recording of the dynamic pressure evolution shows water hammer related pressure fluctuations to occur in the order of 0.1 bar. The pressure fluctuations were higher at higher fluxes (higher velocities) which is in agreement with the theory. They were also more effective at higher fluxes with respect to fouling mitigation. Copyright © 2011 Elsevier Ltd. All rights reserved.

Non-aqueous retention measurement: ultrafiltration behaviour of polystyrene solutions and colloidal silver particles

NARCIS (Netherlands)

Beerlage, M.A.M.; Beerlage, M.A.M.; Heijnen, M.L.; Mulder, M.H.V.; Smolders, C.A.; Smolders, C.A.; Strathmann, H.

1996-01-01

The retention behaviour of polyimide ultrafiltration membranes was investigated using dilute solutions of polystyrene in ethyl acetate as test solutions. It is shown that flow-induced deformation of the polystyrene chains highly affects the membrane retention. This coil-stretch transition is not

Recovery of carbohydrates from nixtamalization wastewaters (nejayote) by ultrafiltration

OpenAIRE

Castro-Muñoz, R.; Cerón-Montes, G.I.; Barragán-Huerta, B.E.; Yáñez-Fernández, J.

2015-01-01

Nejayote extract is a polluting by-product from Nixtamalization of maize; therefore in this study was evaluated a membrane operation for the treatment and recovery of industrial usable compounds. Nejayote extract was processed by ultrafiltration (UF) membrane on laboratory scale. In experimental tests performed according to the total recycle mode, the effect of transmembrane pressure (TMP) on permeate flux has been studied. The permeate flux no showed a considerable increase for TMP values hi...

Microstructured hollow fibers for ultrafiltration

NARCIS (Netherlands)

Culfaz, Pmar Zeynep; Culfaz, P.Z.; Rolevink, Hendrikus H.M.; van Rijn, C.J.M.; Lammertink, Rob G.H.; Wessling, Matthias

2010-01-01

Hollow fiber ultrafiltration membranes with a corrugated outer microstructure were prepared from a PES/PVP blend. The effect of spinning parameters such as air gap, take-up speed, polymer dope viscosity and coagulation value on the microstructure and membrane characteristics was investigated. Fibers

Printing-assisted surface modifications of patterned ultrafiltration membranes

International Nuclear Information System (INIS)

Wardrip, Nathaniel C.; Dsouza, Melissa; Urgun-Demirtas, Meltem; Snyder, Seth W.

2016-01-01

Understanding and restricting microbial surface attachment will enhance wastewater treatment with membranes. We report a maskless lithographic patterning technique for the generation of patterned polymer coatings on ultrafiltration membranes. Polyethylene glycol, zwitterionic, or negatively charged hydrophilic polymer compositions in parallel- or perpendicular-striped patterns with respect to feed flow were evaluated using wastewater. Membrane fouling was dependent on the orientation and chemical composition of the coatings. Modifications reduced alpha diversity in the attached microbial community (Shannon indices decreased from 2.63 to 1.89) which nevertheless increased with filtration time. Sphingomonas species, which condition membrane surfaces and facilitate cellular adhesion, were depleted in all modified membranes. Microbial community structure was significantly different between control, different patterns, and different chemistries. Lastly, this study broadens the tools for surface modification of membranes with polymer coatings and for understanding and optimization of antifouling surfaces.

An equilibrium model for ligand-modified micellar-enhanced ultrafiltration. Selective separation of metal ions using iminoacetic substituted polyamines and a theoretical model for the titration behavior of polyamines

Energy Technology Data Exchange (ETDEWEB)

Dharmawardana, Udeni Rajaratna [Univ. of Oklahoma, Norman, OK (United States)

1992-01-01

This thesis consists of three chapters. Chapter 1, An equilibrium model for ligand-modified micellar-enhanced ultrafiltration, describes a theoretical model and experimental investigations which used the semi-equilibrium-dialysis method with N-n-dodecyl iminodiacetic acid as the ligand. In Chapter 2, Selective separation of metal ions using iminoacetic substituted polyamines, polyamines with a substituted ligand group are synthesized and used in investigating selective separation of copper ions from aqueous solution. In Chapter 3, A theoretical model for the titration behavior of polyamines, a novel approach to explain the titration behavior of polymeric amines based on the binding behavior of counterions is described. The application of this study is to the investigation of inexpensive and efficient methods of industrial waste water treatment.

An improved ultrafiltration method for determining free testosterone in serum

International Nuclear Information System (INIS)

Vlahos, I.; MacMahon, W.; Sgoutas, D.; Bowers, W.; Thompson, J.; Trawick, W.

1982-01-01

In this method, we use the Amicon MPS-1 centrifugal ultrafiltration device and the YMB membrane in measuring free testosterone in serum. Two independent assays are combined: total testosterone and the ultrafiltrable fraction of added [ 3 H]testosterone. The unbound fraction is determined in 0.15-0.5 mL ultrafiltrates of 0.6 to 1 mL of variably diluted serum that has been equilibrated with [ 3 H]testosterone at 37 degrees C. The assay is rapid (less than 1 h), practicable (requires 0.6 mL of serum), and reproducible (CV 3.2% within assay, 3.9% between assays). Accuracy was evaluated as the fraction of free testosterone in the ultrafiltrate of dialyzed serum vs that in a prior dialysate; they were the same confirming the validity of the free testosterone measurement. Samples from ostensibly healthy men and women and from hirsute and pregnant women gave results that agreed with those obtained by equilibrium dialysis. Total testosterone concentrations for normal and hirsute women showed considerable overlap, but data on free testosterone concentrations in these populations were better resolved

Ultrafiltration to reuse laundering wash water

DEFF Research Database (Denmark)

Giagnorio, Mattia; Søtoft, Lene Fjerbæk; Tiraferri, Alberto

2017-01-01

Laundering industry consumes and discharges large amounts of water and surfactants, and the demand of surface active agents used for washing is increasing worldwide. Some of these substances are considered contaminants of emerging concern, as they persist in the environment. This work aimed...... at evaluating the feasibility of ultrafiltration as a method to treat the wash wastewater and possibly reuse the surfactant-rich permeate stream in laundry facilities. In particular, evaluation of surfactant recovery was performed through analysis of the permeate flux and properties obtained through polymeric...... and ceramic membranes. Wash water samples were collected at an industrial laundering facility for hospital linen and filtered through different ultrafiltration membranes with varying molecular weight cut-off. The critical micelle concentration of the detergent was quantified, and capillarity measurements were...

Development of ultrafiltration and inorganic adsorbents for reducing volumes of low-level and intermediate-level liquid waste, April--June 1978

International Nuclear Information System (INIS)

Herald, W.R.; Roberts, R.C.

1978-01-01

A series of runs was performed in which waste processing facility influent was spiked with americium-241, neptunium-237, and uranium-233 and run through the ultrafiltration and reverse osmosis (RO) units. The results of these experiments show that the ultrafiltration membranes are ionic dependent, whereas the RO unit is not. Membrane irradiation studies have been started. Continuous run parameters are being verified through a series of experiments. The small laboratory column tests were continued this quarter on several adsorbents. Decontamination factors were calculated for these adsorbents in removing neptunium-237 and americium-241 from waste solutions. Tests were continued with the 2-in. Engineering Columns using ultrafiltration product spiked with uranium-233. A 6-in. diameter column was installed in the combined raffinate line from the three Engineering Columns. This ''mixed bed'' column will polish the waste solution that is returned to the waste processing facility tanks. A quality control program was started this quarter

Ceramic membrane by tape casting and sol-gel coating for microfiltration and ultrafiltration application

Science.gov (United States)

Das, Nandini; Maiti, H. S.

2009-11-01

Alumina membrane filters in the form of thin (0.3-0.8 mm) discs of 25-30 mm diameter suitable for microfiltration application have been fabricated by tape-casting technique. Further using this microfiltration membrane as substrate, boehmite sol coating was applied on it and ultrafiltration membrane with very small thickness was formed. The pore size of the microfiltration membrane could be varied in the range of 0.1-0.7 μm through optimisation of experimental parameter. In addition, each membrane shows a very narrow pore size distribution. The most important factor, which determines the pore size of the membrane, is the initial particle size and its distribution of the ceramic powder. The top thin ultrafiltration, boehmite layer was prepared by sol-gel method, with a thickness of 0.5 μm. Particle size of the sol was approximately 30-40 nm. The structure and formation of the layer was analysed through TEM. At 550 °C formation of the top layer was completed. The pore size of the ultrafiltration membrane measured from TEM micrograph was almost 10 nm. Results of microbial (Escherichia coli—smallest-sized water-borne bacteria) test confirm the possibility of separation through this membrane

A Modified EPA Method 1623 that Uses Tangential Flow Hollow-Fiber Ultrafiltration and Heat Dissociation Steps to Detect Waterborne Cryptosporidum and Giardia spp.

Science.gov (United States)

This protocol describes the use of a tangential flow hollow-fiber ultrafiltration sample concentration system and a heat dissociation as alternative steps for the detection of waterborne Cryptosporidium and Giardia species using EPA Method 1623.

Removal of uranium and thorium from aqueous solution by ultrafiltration (UF) and PAMAM dendrimer assisted ultrafiltration (DAUF)

International Nuclear Information System (INIS)

Ilaiyaraja, P.; Ashish Kumar Singha Deb; Ponraju, D.

2015-01-01

Studies on removal of U(VI) and Th(IV) from aqueous solution have been carried out by ultrafiltration (UF) and dendrimer assisted ultrafiltration (DAUF) using regenerated cellulose acetate membrane and PAMAM [poly(amido)amine] dendrimer chelating agent. In UF, the U(VI) and Th(IV) are removed from aqueous solution by adsorption/mass deposition on the membrane at pH > 4. In DAUF, the water soluble PAMAM dendrimer chelating agent effectively concentrates these metal ions in retentate thereby preventing the mass deposition on membrane. At acidic pH (≤3), the binding of metal ions with PAMAM dendrimer is very weak and hence PAMAM can be regenerated and reused. Electronic supplementary material. The online version of this article (doi:10.1007/s10967-014-3462-x) contains supplementary material, which is available to authorized users. (author)

Drinking water treatment by ultrafiltration membranes; Potabilizacion de aguas mediante membranas de ultrafiltracion

Energy Technology Data Exchange (ETDEWEB)

Rojas, J. C.; Moreno, B.; Poyatos, J. M.; Rua, A. de la; Perez, J. J.; Plaza, F.; Garralon, G.; Gomez, M. A.

2007-07-01

In this paper the application of ultrafiltration technology as a drinking water treatment was evaluated. For this reason, a pilot scale ultrafiltration module equipped with a flat membrane cassette of polyvinylidene fluoride (PVDF) with an average pore size of 0.05 {mu}m was used. Different types of artificially polluted waters (with urban waste water and soil suspension) were used. the performance of ultrafiltration technology was evaluated by means of different physicochemical and microbiological parameters both feed water and treated water. Bacterial and viral indicators were efficiently retained by the system and the same time organoleptic parameters were improved. However, it is important to emphasize the problems that the ultrafiltration technology has for the eliminate dissolves compounds remaining the most dissolve organic compounds in the feed water. (Author) 11 refs.

Differential natural organic matter fouling of ceramic versus polymeric ultrafiltration membranes.

Science.gov (United States)

Lee, Seung-Jin; Kim, Jae-Hong

2014-01-01

Ceramic ultrafiltration membranes has drawn increasing attention in drinking water treatment sectors as an alternative to traditional polymeric counterparts, yet only limited information has been made available about the characteristics of ceramic membrane fouling by natural organic matter. The effects of solution chemistry including ionic strength, divalent ion concentration and pH on the flux behavior were comparatively evaluated for ceramic and polymeric ultrafiltration of synthetic water containing model natural organic matter. Filtration characteristics were further probed via resistance-in-series model analysis, fouling visualization using quantum dots, batch adsorption test, contact angle measurement, solute-membrane surface adhesion force measurement, and quantitative comparison of fouling characteristics between ceramic and polymeric membranes. The results collectively suggested that the effects of solution chemistry on fouling behavior of ceramic membranes were generally similar to polymeric counterparts in terms of trends, while the extent varied significantly depending on water quality parameters. Lower fouling tendency and enhanced cleaning efficiency were observed with the ceramic membrane, further promoting the potential for ceramic membrane application to surface water treatment. Copyright © 2013 Elsevier Ltd. All rights reserved.

Development of new ultrafiltration techniques maintaining in-situ hydrochemical conditions for colloidal study

International Nuclear Information System (INIS)

Aosai, Daisuke; Yamamoto, Yuhei; Mizuno, Takashi

2011-01-01

Chemical state of elements in groundwater is one of the most important information for understanding behavior of elements in underground environment. Chemical state of elements controlled mainly by groundwater physico-chemical parameters. Because the change of physico-chemical parameters of groundwater, due to pressure release and oxidation during sampling, causes changes in chemical state of elements, systematic methodologies for understanding in situ chemical state is required. In this study, in order to understand chemical state of elements in groundwater, an ultrafiltration instrument for maintaining in-situ pressure and anaerobic conditions was developed. The instrument developed in this study for ultrafiltration made of passivated Stainless Used Steel (SUS) materials, was designed to keep groundwater samples maintaining in-situ pressure/anaerobic conditions. Ultrafiltration of groundwater was conducted at a borehole drilled from the 200 mbGL (meters below ground level) Sub-stage at a depth of 200 m at the Mizunami Underground Research Laboratory. Chemical analyses of groundwater were also conducted using samples filtered under both pressurized/anaerobic and atmospheric conditions and passivated SUS materials with different elapsed times after passivation. The results indicate that our ultrafiltration method is suitable for collection of filtered groundwater and passivation is an essential treatment before ultrafiltration. (author)

CROSS-FLOW ULTRAFILTRATION OF SECONDARY EFFLUENTS. MEMBRANE FOULING ANALYSIS

Directory of Open Access Journals (Sweden)

Luisa Vera

2014-12-01

Full Text Available The application of cross-flow ultrafiltration to regenerate secondary effluents is limited by membrane fouling. This work analyzes the influence of the main operational parameters (transmembrane pressure and cross-flow velocity about the selectivity and fouling observed in an ultrafiltration tubular ceramic membrane. The experimental results have shown a significant retention of the microcolloidal and soluble organic matter (52 – 54% in the membrane. The fouling analysis has defined the critical operational conditions where the fouling resistance is minimized. Such conditions can be described in terms of a dimensionless number known as shear stress number and its relationship with other dimensionless parameter, the fouling number.

Low fouling polysulfone ultrafiltration membrane via click chemistry

KAUST Repository

Xie, Yihui

2014-10-13

Hydrophilic surfaces are known to be less prone to fouling. Ultrafiltration membranes are frequently prepared from rather hydrophobic polymers like polysulfone (PSU). Strategies to keep the good pore forming characteristics of PSU, but with improved hydrophilicity are proposed here. PSU functionalized with 1,2,3-triazole ring substituents containing OH groups was successfully synthesized through click chemistry reaction. The structures of the polymers were confirmed using NMR spectroscopy and Fourier transform infrared spectroscopy (FTIR). High thermal stability (>280°C) was observed by thermal gravimetric analysis. Elemental analysis showed the presence of nitrogen containing triazole group with different degrees of functionalization (23%, 49%, 56%, and 94%). The glass transition temperature shifted with the introduction of triazole pendant groups from 190°C (unmodified) to 171°C. Ultrafiltration membranes were prepared via phase inversion by immersion in different coagulation baths (NMP/water mixtures with volume ratios from 0/100 to 40/60). The morphologies of these membranes were studied by field emission scanning electron microscopy (FESEM). The optimized PSU bearing triazole functions membranes exhibited water permeability up to 187 L m-2 h-1 bar-1, which is 23 times higher than those prepared under the same conditions but with unmodified polysulfone (PSU; 8 L m-2 h-1 bar-1). Results of bovine serum albumin protein rejection test indicated that susceptibility to fouling decreased with the modification, due to the increased hydrophilicity, while keeping high protein rejection ratio (>99%).

Microfiltration and Ultrafiltration Membranes for Drinking Water

Science.gov (United States)

This article provides a concise and abbreviated summary of AWWA Manual of Practice M53, Microfiltration and Ultrafiltration Membranes for Drinking Water, to serve as a quick point of reference. For convenience, the article’s organization matches that of M53, as follows: • wate...

Characterization of clean and fouled ultrafiltration membranes

NARCIS (Netherlands)

Hanemaaijer, J.H.; Robbertsen, T.; van den Boomgaard, Anthonie; Olieman, C.; Both, P.; Schmidt, D.G.

1988-01-01

Much research into the fundamentals of membrane formation and separation has been performed in order to improve the efficiency of the manufacture of ultrafiltration membranes. Determination of the membrane characteristics is a key problem in these investigations. In this paper, we report on a study

Increasing Water System Efficiency with Ultrafiltration Pre-treatment in Power Plants

International Nuclear Information System (INIS)

Majamaa, Katariina; Suarez, Javier; Gasia Eduard

2012-09-01

Water demineralization with reverse osmosis (RO) membranes has a long and successful history in water treatment for power plants. As the industry strives for more efficient, reliable and compact water systems, pressurized hollow-fiber ultrafiltration (UF) has become an increasingly appealing pre-treatment technology. Compared to conventional, non- membrane based pretreatments, ultrafiltration offers higher efficiency in the removal of suspended solids, microorganisms and colloidal matter, which are all common causes for operational challenges experienced in the RO systems. In addition, UF is more capable of handling varying feed water qualities and removes the risk of particle carry-over often seen with conventional filtration techniques. Ultrafiltration is a suitable treatment technology for various water types from surface waters to wastewater, and the more fluctuating or challenging the feed water source is, the better the benefits of UF are seen compared to conventional pretreatments. Regardless of the feed water type, ultrafiltration sustains a constant supply of high quality feed water to downstream RO, allowing a more compact and cost efficient RO system design with improved operational reliability. A detailed focus on the design and operational aspects and experiences of two plants is provided. These examples demonstrate both economical UF operation and tangible impact of RO process improvement. Experience from these plants can be leveraged to new projects. (authors)

Treatment of olive mill wastewater by the combination of ultrafiltration and bipolar electrochemical reactor processes

KAUST Repository

Yahiaoui, O.; Lounici, Hakim; Abdi, Nadia; Drouiche, Nadjib; Ghaffour, NorEddine; Pauss, André ; Mameri, Nabil

2011-01-01

The main purpose of this study was to investigate the removal of the chemical oxygen demand (COD) from olive mill wastewater (OMW) by the combination of ultrafiltration with electrocoagulation process. Ultrafiltration process equipped with CERAVER

Application of Ultrafiltration in a Paper Mill: Process Water Reuse and Membrane Fouling Analysis

Directory of Open Access Journals (Sweden)

Chen Chen

2015-02-01

Full Text Available High water consumption is a major environmental problem that the pulp and paper industry is facing. Ultrafiltration (UF can be used to remove the dissolved and colloidal substances (DCS concentrated during the recycling of white water (the process water to facilitate the reuse of white water and reduce fresh water consumption. However, membrane fouling limits the application of UF in this industry. In this study, super-clear filtrate obtained from a fine paper mill was purified with a polyethersulfone (PES ultrafiltration membrane to evaluate the reuse performance of the ultrafiltrate. The membrane foulants were characterized by scanning electron microscopy, energy-dispersive spectrophotometry, attenuated total reflection-fourier transform infrared spectroscopy, and gas chromatography-mass spectrometry. The results indicate that the retention rate of stock and the strength properties of paper increased when the ultrafiltrate was reused in the papermaking process compared to when super-clear filtrate was used. The reversible membrane foulants during ultrafiltration accounted for 85.52% of the total foulants and primarily originated from retention aids, drainage aids, and wet strength resins, while the irreversible adsorptive foulants accounted for 14.48% and mostly came from sizing agents, coating chemicals, and others. Moreover, the presence of dissolved multivalent metal ions, especially Ca2+, accelerated membrane fouling.

The potentialities of the complexation ultrafiltration technique for the decontamination of fission product contaminated aqueous effluents; Potentialites de la complexation - ultrafiltration a la decontamination d`effluents radioactifs en produits de fission

Energy Technology Data Exchange (ETDEWEB)

Thibert, V

1995-07-01

Many nuclear researchers and industrial operators lay emphasis on improving the back end of the fuel cycle. A major problem concerns the liquid wastes generated by the reprocessing plant at La Hague, discharged into the sea after treatment in the Effluent Treatment Station (STE) (3), and which have become crucial matter. The activity of these wastes is well below the current legal limits, and is constantly decreasing these last years. To bring it close to zero, and ambitious goal, entails innovative new reprocessing techniques. We accordingly investigated the possibilities of complexation-ultrafiltration, a technique that uses water-soluble macromolecules to complex the target elements to be separated. We first achieved the strontium (II) separation with poly-acrylic and poly-sulfonic acids. The effects of pH and NaNO{sub 3} concentration influence on Sr (II) complexation were studied. The Sr (II) complexation and concentration phases, followed by cation de-complexation to recover the polymer, were also taken into account. This research, combined with a potentiometric study of the polymers, offered a close understanding of the chemical systems involved, and of the operating conditions and limits of complexation-ultrafiltration. The laboratory results were also validated on a tangential ultrafiltration pilot plant. We then used complexation-ultrafiltration to treat a real effluent generated bu La Hague`s STE 3 plant. This experiment demonstrated minimum 90 % decontamination of Sr (II) (with polyacrylate complexing agent), and also for {sup 134-137}Cs (with simple ultrafiltration). The use of two polyamides allowed partial decontamination of the effluent for {sup 60}Co and {sup 106}Ru. This work therefore offers a global approach to complexation-ultrafiltration, from laboratory to pilot scale, on real and simulated effluents. The future of this technique relies chiefly on the ability to solve the problem of polymer recovery. (Abstract Truncated)

Development of ultrafiltration and inorganic adsorbents for reducing volumes of low-level and intermediate-level liquid waste: October--December 1977

International Nuclear Information System (INIS)

Koenst, J.W.; Herald, W.R.; Roberts, R.C.

1978-01-01

The exposures of noncellulosic ultrafiltration membranes to a radioactive environment simulating up to 24 months of exposure to a β dose of 10 μCi/cm 3 , a γ dose of 10 -5 μCi/cm 3 , and an α dose of 4.9 x 10 -3 μCi/cm 3 were completed. Exposure to β and γ radiation did not affect membrane performance. After a simulated six months of exposure to α radiation some degradation of membrane performance occurred. Several experiments were made on a laboratory-scale reverse-osmosis unit using the product from ultrafiltration as feed. Rejection of activity ranged from 88 to 99 percent. The ''continuous'' ultrafiltration pilot run was completed. Approximately 40,000 gal were processed in over 70 hr of operating time without shutdown for cleaning. Flux and rejection were maintained relatively steady over this period. Rejection of gross alpha ranged from 80 to 99.5 percent depending on the ionic content of the waste stream. Flux rates ranged from 5 to 8 liters/min over this period. The engineering column tests were continued using uranium-233 with product from the ultrafiltration pilot plant. Flow rates and pH were varied in order to determine optimum operating conditions

Sequential micro and ultrafiltration of distillery wastewater

Directory of Open Access Journals (Sweden)

Vasić Vesna M.

2015-01-01

Full Text Available Water reuse and recycling, wastewater treatment, drinking water production and environmental protection are the key challenges for the future of our planet. Membrane separation technologies for the removal of all suspended solids and a fraction of dissolved solids from wastewaters, are becoming more and more promising. Also, these processes are playing a major role in wastewater purification systems because of their high potential for recovery of water from many industrial wastewaters. The aim of this work was to evaluate the application of micro and ultrafiltration for distillery wastewater purification in order to produce water suitable for reuse in the bioethanol industry. The results of the analyses of the permeate obtained after micro and ultrafiltration showed that the content of pollutants in distillery wastewater was significantly reduced. The removal efficiency for chemical oxygen demand, dry matter and total nitrogen was 90%, 99.2% and 99.9%, respectively. Suspended solids were completely removed from the stillage.

Low fouling polysulfone ultrafiltration membrane via click chemistry

KAUST Repository

Xie, Yihui; Tayouo Djinsu, Russell; Nunes, Suzana Pereira

2014-01-01

%, and 94%). The glass transition temperature shifted with the introduction of triazole pendant groups from 190°C (unmodified) to 171°C. Ultrafiltration membranes were prepared via phase inversion by immersion in different coagulation baths (NMP

Treatment of simulated plutonium-containing wastewater by ultrafiltration-reverse osmosis technology

International Nuclear Information System (INIS)

Xiong Zhonghua; Fan Xianhua; Luo Deli; Wang Tuo; Chen Qi

2008-01-01

Ultrafiltration and reverse osmosis were employed for the treatment of low level radioactive water containing plutonium. The system consists of ultrafiltration module with hollow fibre membrane and reverse osmosis module with spiral membrane. The decontamination efficiency and volume concentration ratio affected by technical parameters were explored in the experiment. The results show that the decontamination efficiency achieves 99.94% and the volume concentration ratio achieves 12.5 at pH=10 for solution fed into the membrane separation system. This technology will be applied in radioactive waste minimization as a new treatment method. (authors)

Antifouling Ultrafiltration Membranes via Post-Fabrication Grafting of Biocidal Nanomaterials

KAUST Repository

Mauter, Meagan S.; Wang, Yue; Okemgbo, Kaetochi C.; Osuji, Chinedum O.; Giannelis, Emmanuel P.; Elimelech, Menachem

2011-01-01

Figure Presented: Ultrafiltration (UF) membranes perform critical pre-treatment functions in advanced water treatment processes. In operational systems, however, biofouling decreases membrane performance and increases the frequency and cost of chemical cleaning. The present work demonstrates a novel technique for covalently or ionically tethering antimicrobial nanoparticles to the surface of UF membranes. Silver nanoparticles (AgNPs) encapsulated in positively charged polyethyleneimine (PEI) were reacted with an oxygen plasma modified polysulfone UF membrane with and without 1-ethyl-3-(3- dimethylaminopropyl) carbodiimide hydrochloride (EDC) present. The nucleophilic primary amines of the PEI react with the electrophilic carboxyl groups on the UF membrane surface to form electrostatic and covalent bonds. The irreversible modification process imparts significant antimicrobial activity to the membrane surface. Post-synthesis functionalization methods, such as the one presented here, maximize the density of nanomaterials at the membrane surface and may provide a more efficient route for fabricating diverse array of reactive nanocomposite membranes. © 2011 American Chemical Society.

Antifouling Ultrafiltration Membranes via Post-Fabrication Grafting of Biocidal Nanomaterials

KAUST Repository

Mauter, Meagan S.

2011-08-24

Figure Presented: Ultrafiltration (UF) membranes perform critical pre-treatment functions in advanced water treatment processes. In operational systems, however, biofouling decreases membrane performance and increases the frequency and cost of chemical cleaning. The present work demonstrates a novel technique for covalently or ionically tethering antimicrobial nanoparticles to the surface of UF membranes. Silver nanoparticles (AgNPs) encapsulated in positively charged polyethyleneimine (PEI) were reacted with an oxygen plasma modified polysulfone UF membrane with and without 1-ethyl-3-(3- dimethylaminopropyl) carbodiimide hydrochloride (EDC) present. The nucleophilic primary amines of the PEI react with the electrophilic carboxyl groups on the UF membrane surface to form electrostatic and covalent bonds. The irreversible modification process imparts significant antimicrobial activity to the membrane surface. Post-synthesis functionalization methods, such as the one presented here, maximize the density of nanomaterials at the membrane surface and may provide a more efficient route for fabricating diverse array of reactive nanocomposite membranes. © 2011 American Chemical Society.

Ultrafiltration treatment for liquid laundry wastes from nuclear power stations

International Nuclear Information System (INIS)

Kichik, V.A.; Maslova, M.N.; Svittsov, A.A.; Kuleshov, N.F.

1988-01-01

The authors conduct a comprehensive analysis of the waste constituents--radioactive and organic--of the laundry water resulting from the on-site laundering and decontamination of clothing worn in nuclear power plants. The primary isotope contaminants consist of niobium and zirconium 95, manganese 54, cobalt 60, iron 59, and cesium 134 and 137. A variety of filter and adsorbent materials used in an ultrafiltration process are comparatively tested for their effectiveness in removing not only these isotopes but also the organic contaminants in the process of recycling the water. Those materials consist of copper hexacyanoferrate, polyacrylophosphonic acid, and several metal-polymer complexes

Development of ultrafiltration and inorganic adsorbents for reducing volumes of low-level and intermediate-level liquid waste: July--September 1977

International Nuclear Information System (INIS)

Koenst, J.W.; Herald, W.R.; Roberts, R.C.

1978-01-01

The ultrafiltration (UF) pilot system is being evaluated at Mound Facility. The effect of pressure drop, temperature, and pH of the feed on system performance has been studied. The system has been run through a number of cleaning cycles including tap water flush, enzyme soak, detergent wash, and citric acid/oxalic acid wash. A continuous run was started on waste from the Waste Processing Facility; about 11,500 gal has been processed. Studies to determine the effect of (α, β, and γ) radiation on membrane characteristics were initiated. The small laboratory column tests were completed. Isotherms were run on several inorganic adsorbents, including titanium phosphate and sodium titanate. Tests were continued on the Engineering Test Ion Exchange System. Waste solution from the Waste Processing Facility spiked with plutonium-238 and ultrafiltration product spiked with uranium-233 were used as feeds. 6 tables, 1 figure

Identification of the Allergenic Ingredients in Reduning Injection by Ultrafiltration and High-Performance Liquid Chromatography

Directory of Open Access Journals (Sweden)

Fang Wang

2016-01-01

Full Text Available Reduning injection is a traditional Chinese medicine injection which has multiple functions such as clearing heat, dispelling wind, and detoxification. Although Reduning injection was widely utilized, reports of its allergenicity emerged one after another. However, there is little research on its allergenic substances. The aim of this study is to evaluate the sensitization of Reduning injection and explore the underlying cause of the anaphylactic reaction. The main ingredients in Reduning injection were analyzed before and after ultrafiltration. Ultrafiltrate Reduning injection, unfiltered Reduning injection, egg albumin, Tween-80, and nine effective components in Reduning injection were utilized to sensitize guinea pigs. The serum 5-hydroxytryptamine level was used to assess the sensitization effect of Reduning injection. We found a significant decrease in Tween-80 content comparing to other components in the injection after ultrafiltration. Unfiltered Reduning injection, Tween-80, chlorogenic acid, and cryptochlorogenin acid caused remarkable anaphylactoid reaction on guinea pigs while ultrafiltration Reduning resulted in a significantly lower degree of sensitization. Our results suggest that ultrafiltration could significantly reduce the sensitization of Reduning injection, which is likely due to the decrease of Tween-80. We also conjectured that the form of chlorogenic acid and cryptochlorogenin acid within the complex solution mixture may also affect the sensitizing effect.

Ceramic membrane ultrafiltration of natural surface water with ultrasound enhanced backwashing.

Science.gov (United States)

Boley, A; Narasimhan, K; Kieninger, M; Müller, W-R

2010-01-01

Ultrafiltration membrane cleaning with ultrasound enhanced backwashing was investigated with two ceramic membrane systems in parallel. One of them was subjected to ultrasound during backwashing, the other acted as a reference system. The feed water was directly taken from a creek with a sedimentation process as only pre-treatment. The cleaning performance was improved with ultrasound but after 3 weeks of operation damages occurred on the membranes. These effects were studied with online measurements of flux, trans-membrane-pressure and temperature, but also with integrity tests, turbidity measurements and visual examination.

Increased saccharification of kallar grass using ultrafiltrated enzyme from sporrotrichum thermophile

International Nuclear Information System (INIS)

Latif, F.; Rajoka, M.I.; Malik, K.A.

1991-01-01

The local wild type strain of sporotrichum thermophile when grown on untreated lingo cellulose was found to produce a greater level of B-glucosidase component along with other cellulase/xylanase components than most of the reported wild type potent strains. Culture filtrate obtained, when grown on 4% leptochloa fusca (kallar grass) was used as such and after concentration by ultrafiltration technique for saccharification purpose. Concentrated enzymes titre was increased to 1.2 and 4.0 U/ml for Fp-ase and B-glucosidase, respectively. There were losses in the enzyme titre obtained through ultrafiltration possibly due to adsorption on to the ultrafiltration membrane. Enzyme preparations used, saccharifide 5% kallar grass to 70, 55, 75 and 60% (theoretical basis) from cellulases of S. thermophile concentrate, dilute, T. reesei alone and in supplementation with B-glucosidase from A. niger, respectively. Analysis by HPLC revealed slightly higher glucose yield from S. thermophile enzyme preparations, whereas higher level of xylose was attained from T. reesei preparations. Rest of the sugars pooled as Oligo-sugars were found in almost similar concentrations. (author)

Fouling reduction by ozone-enhanced backwashing process in ultrafiltration of petroleum-based oil in water emulsion

Science.gov (United States)

Aryanti, Nita; Prihatiningtyas, Indah; Kusworo, Tutuk Djoko

2017-06-01

Ultrafiltration membrane has been successfully applied for oily waste water treatment. However, one significant drawback of membrane technology is fouling which is responsible for permeate flux decline as well as reducing membrane performance. One method commonly used to reduce fouling is a backwashing process. The backwashing is carried out by a push of reversed flow from permeate side to the feed side of a membrane to remove fouling on the membrane pore and release fouling release fouling layer on the external side. However, for adsorptive fouling, the backwashing process was not effective. On the other hand, Ozone demonstrated great performance for reducing organics fouling. Hence this research was focused on backwashing process with ozone for removing fouling due to ultrafiltration of petroleum based oil emulsion. Gasoline and diesel oil were selected as dispersed phase, while as continuous phase was water added with Tween 80 as a surfactant. This research found that the Ozone backwashing was effective to improve flux recovery. In ultrafiltration of gasoline emulsion, the flux recovery after Ozone backwashing was in the range of 42-74%. For ultrafiltration of diesel oil emulsion, the permeate flux recovery was about 35-84%. In addition, foulant deposition was proposed and predicting that foulant deposition for ultrafiltration of gasoline-in-water emulsion was surfactant as the top layer and the oil was underneath the surfactant. On the other hand, for ultrafiltration of diesel oil-in-water emulsion, the oil was predicted as a top layer above the surfactant foulant.

Physicochemical and Microbiological Properties of Yogurt-cheese Manufactured with Ultrafiltrated Cow's Milk and Soy Milk Blends

OpenAIRE

Lee, Na-Kyoung; Mok, Bo Ram; Jeewanthi, Renda Kankanamge Chaturika; Yoon, Yoh Chang; Paik, Hyun-Dong

2015-01-01

The objective of this study was to develop yogurt-cheese using cow?s milk, ultrafiltrated cow?s milk, and soy milk. The addition of soy milk and ultrafiltrated milk increased the amount of protein in the yogurt-cheese. Yogurt-cheeses were made using cheese base using 10% and 20% soy milk with raw and ultrafiltrated cow?s milk, and stored at 4? during 2 wk. The yield of yogurt-cheeses made with added soy milk was decreased and the cutting point was delayed compared to yogurt-cheese made withou...

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.

The determination of ultrafiltrable calcium and magnesium in serum.

Science.gov (United States)

Danielson, B G; Pallin, E; Sohtell, M

1982-01-01

Ultrafiltrate of human serum was investigated in order to evaluate the serum content of calcium and magnesium. The acid and base concentrations and pH of the serum was altered through titration with HCl- or NaOH-solutions. The Pco2 was varied in the titrated serum using different carbon dioxide tensions. This was performed when serum was filtered in a recycling system. It is shown that the analysis of calcium and magnesium have to be done under anaerobic conditions or at standardized pH and Pco2 situations, as the concentrations vary with both pH and Pco2. The concentration ratio between ultrafiltrate and serum for calcium and magnesium was found to be 0.56 and 0.74 respectively at pH=7.41 and Pco2=40 mmHg.

The potentialities of the complexation ultrafiltration technique for the decontamination of fission product contaminated aqueous effluents

International Nuclear Information System (INIS)

Thibert, V.

1995-07-01

Many nuclear researchers and industrial operators lay emphasis on improving the back end of the fuel cycle. A major problem concerns the liquid wastes generated by the reprocessing plant at La Hague, discharged into the sea after treatment in the Effluent Treatment Station (STE) 3), and which have become crucial matter. The activity of these wastes is well below the current legal limits, and is constantly decreasing these last years. To bring it close to zero, and ambitious goal, entails innovative new reprocessing techniques. We accordingly investigated the possibilities of complexation-ultrafiltration, a technique that uses water-soluble macromolecules to complex the target elements to be separated. We first achieved the strontium (II) separation with poly-acrylic and poly-sulfonic acids. The effects of pH and NaNO 3 concentration influence on Sr (II) complexation were studied. The Sr (II) complexation and concentration phases, followed by cation de-complexation to recover the polymer, were also taken into account. This research, combined with a potentiometric study of the polymers, offered a close understanding of the chemical systems involved, and of the operating conditions and limits of complexation-ultrafiltration. The laboratory results were also validated on a tangential ultrafiltration pilot plant. We then used complexation-ultrafiltration to treat a real effluent generated bu La Hague's STE 3 plant. This experiment demonstrated minimum 90 % decontamination of Sr (II) (with polyacrylate complexing agent), and also for 134-137 Cs (with simple ultrafiltration). The use of two polyamides allowed partial decontamination of the effluent for 60 Co and 106 Ru. This work therefore offers a global approach to complexation-ultrafiltration, from laboratory to pilot scale, on real and simulated effluents. The future of this technique relies chiefly on the ability to solve the problem of polymer recovery. In other respect, complexation-ultrafiltration clearly offers a

FLUX PROFILES AND MATHEMATICAL MODELING OF FOULING MECHANISM FOR ULTRAFILTRATION OF KONJAC GLUCOMANNAN

Directory of Open Access Journals (Sweden)

NITA ARYANTI

2016-07-01

Full Text Available This study was focused on principles and fouling analysis of konjac glucomannan (KGM separation using ultrafiltration system. Two Polyethersulfone membranes (PES having molecular weight cut-off of 10 and 20 kDa were used. It was found that membrane having larger pore size provided higher flux profiles. Evaluation of different transmembrane pressures resulted on possibility of more severe fouling at higher membrane pressure. With the increase of konjac glucomannan concentration, decrease of profile flux was observed. Further, a simple mathematical modelling of fouling mechanism was analyzed based on Hermia’s model. The images of membrane surfaces and cross-sections obtained by scanning electron microscopy (SEM were examined and being compared with the model. The research found that the fouling mechanisms of KGM ultrafiltration using membrane with pore size of 10 kDa was complete blocking. On the contrary, cake/gel layer formation was a fouling mechanism for ultrafiltration system with pore size of 20kDa.

Ultrafiltration concept for separating oil from water. Final report

Energy Technology Data Exchange (ETDEWEB)

Goldsmith, R.L.; Schrab H.

1973-01-01

Discharge of oily wastes from shipboard operations of deballasting, bilge pumping, and slop tank cleaning constitutes a serious water pollution problem. Membrane ultrafiltration was studied in this project as a means of generating a highly purified water from a variety of oily wastes.

Cosmological tests of modified gravity.

Science.gov (United States)

Koyama, Kazuya

2016-04-01

We review recent progress in the construction of modified gravity models as alternatives to dark energy as well as the development of cosmological tests of gravity. Einstein's theory of general relativity (GR) has been tested accurately within the local universe i.e. the Solar System, but this leaves the possibility open that it is not a good description of gravity at the largest scales in the Universe. This being said, the standard model of cosmology assumes GR on all scales. In 1998, astronomers made the surprising discovery that the expansion of the Universe is accelerating, not slowing down. This late-time acceleration of the Universe has become the most challenging problem in theoretical physics. Within the framework of GR, the acceleration would originate from an unknown dark energy. Alternatively, it could be that there is no dark energy and GR itself is in error on cosmological scales. In this review, we first give an overview of recent developments in modified gravity theories including f(R) gravity, braneworld gravity, Horndeski theory and massive/bigravity theory. We then focus on common properties these models share, such as screening mechanisms they use to evade the stringent Solar System tests. Once armed with a theoretical knowledge of modified gravity models, we move on to discuss how we can test modifications of gravity on cosmological scales. We present tests of gravity using linear cosmological perturbations and review the latest constraints on deviations from the standard [Formula: see text]CDM model. Since screening mechanisms leave distinct signatures in the non-linear structure formation, we also review novel astrophysical tests of gravity using clusters, dwarf galaxies and stars. The last decade has seen a number of new constraints placed on gravity from astrophysical to cosmological scales. Thanks to on-going and future surveys, cosmological tests of gravity will enjoy another, possibly even more, exciting ten years.

High Concentration Protein Ultrafiltration: a Comparative Fouling Assessment

Science.gov (United States)

Lim, Y. P.; Mohammad, A. W.

2018-05-01

In this paper, the predominant fouling mechanism via pH manipulation in gelatin ultrafiltration (UF) at constant operating pressure was studied. Two 30 kDa molecular weight cut off (MWCO) UF membranes with different hydrophilic/hydrophobic properties were tested at solution pH near gelatin isoelectric point (IEP), pH below and above gelatin’s IEP. The resistance-in-series model was used to determine quantitatively the contribution of each filtration resistance occurred during gelatin UF. The governing fouling mechanisms were investigated using classical blocking laws. The results demonstrated that concentration polarization remain as dominant fouling resistance in gelatin UF, but exceptional case was observed at pH away from gelatin’s IEP, showing that combined reversible and irreversible fouling resistances contributed around 57% and 37%, respectively to the overall fouling resistances. Under all experimental condition tested, permeate flux decline was accurately predicted by all the models studied. Fouling profile was fitted well with “Standard Blocking”, “Intermediate Blocking” and “Cake Filtration” model for regenerated cellulose acetate (RCA) membrane and “Cake Filtration” model for polyethersulphone (PES) membrane.

Characterization and utilization of the permeate and retentate obtained after “dead-end” ultrafiltration

Directory of Open Access Journals (Sweden)

Vasić Vesna M.

2013-01-01

Full Text Available In the recent years, with the increase in bioethanol production, the increasing amounts of distillery wastewater are generated. Such wastewater (stillage is one of the most polluted waste product of the food and beverage industries. The present study evaluates the treatment of distillery wastewater by ultrafiltration (UF, in order to reduce its pollution and evaluate the composition of the permeate and retentate. Polyethersulfone ultrafiltration membrane with molecular weight cut-off (MWCO 30000 Da, was used for the experiments. The UF was carried out in dead-end mode. The results of the analyses of the permeate and retentate obtained after ultrafiltration were considered as well as different ways for their further utilization. The pollutant level in the permeate was decreased significantly in comparison to the raw stillage, and suspended solids were completely removed from the stillage. [Projekat Ministarstva nauke Republike Srbije, br. TR 31002

Separation of racemic mixture by ultrafiltration of enantioselective micelles. 1 Effect of pH on separation and regeneration

NARCIS (Netherlands)

Overdevest, P.E.M.; Bruin, de T.J.M.; Riet, van 't K.; Keurentjes, J.T.F.; Padt, van der A.

2001-01-01

Many enantiomer separation systems are studied to meet the increasing demand for enantiopure compounds. One way to obtain pure enantiomers is to apply enantioselective micelles in ultrafiltration systems. We have studied the separation of phenylalanine (Phe) enantiomers by the ultrafiltration of

Dynamic modeling of ultrafiltration membranes for whey separation processes

NARCIS (Netherlands)

Saltik, M.B.; Ozkan, L.; Jacobs, M.; van der Padt, A.

2017-01-01

In this paper, we present a control relevant rigorous dynamic model for an ultrafiltration membrane unit in a whey separation process. The model consists of a set of differential algebraic equations and is developed for online model based applications such as model based control and process

Effect of Time in Chemical Cleaning of Ultrafiltration Membranes

NARCIS (Netherlands)

Levitsky, I.; Naim, R.; Duek, A.; Gitis, V.

2012-01-01

Chemical cleaning of ultrafiltration membranes is often considered successful when the flux through a cleaned membrane is much higher than through a pristine one. Here, a novel definition of cleaning intensity is proposed as the product of the concentration of the cleaning agent and the cleaning

Modifying the test of understanding graphs in kinematics

Science.gov (United States)

Zavala, Genaro; Tejeda, Santa; Barniol, Pablo; Beichner, Robert J.

2017-12-01

In this article, we present several modifications to the Test of Understanding Graphs in Kinematics. The most significant changes are (i) the addition and removal of items to achieve parallelism in the objectives (dimensions) of the test, thus allowing comparisons of students' performance that were not possible with the original version, and (ii) changes to the distractors of some of the original items that represent the most frequent alternative conceptions. The final modified version (after an iterative process involving four administrations of test variations over two years) was administered to 471 students of an introductory university physics course at a large private university in Mexico. When analyzing the final modified version of the test it was found that the added items satisfied the statistical tests of difficulty, discriminatory power, and reliability; also, that the great majority of the modified distractors were effective in terms of their frequency selection and discriminatory power; and, that the final modified version of the test satisfied the reliability and discriminatory power criteria as well as the original test. Here, we also show the use of the new version of the test, presenting a new analysis of students' understanding not possible to do before with the original version of the test, specifically regarding the objectives and items that in the new version meet parallelisms. Finally, in the PhysPort project (physport.org), we present the final modified version of the test. It can be used by teachers and researchers to assess students' understanding of graphs in kinematics, as well as their learning about them.

Making equipment to process paddy water for providing drinking water by using Ozone-UVC& Ultrafiltration

Science.gov (United States)

Styani, E.; Dja'var, N.; Irawan, C.; Hanafi

2018-01-01

This study focuses on making equipment which is useful to process paddy water to be consumable as drinking water by using ozone-UVC and ultrafiltration. The equipment which is made by the process of ozone-UVC and ultrafiltration or reverse osmosis is driven by electric power generated from solar panels. In the experiment, reverse osmosis system with ozone-UVC reactor proves to be good enough in producing high quality drinking water.

Combining electrophoresis with detection under ultraviolet light and multiple ultrafiltration for isolation of humic fluorescence fractions.

Science.gov (United States)

Trubetskaya, Olga E; Shaloiko, Lubov A; Demin, Dmitrii V; Marchenkov, Victor V; Proskuryakov, Ivan I; Coelho, Christian; Trubetskoj, Oleg A

2011-04-01

Polyacrylamide gel electrophoresis of chernozem soil humic acids (HAs) followed by observation under UV (312 nm) excitation light reveals new low molecular weight (MW) fluorescent fractions. Ultrafiltration of HAs sample in 7 M urea on a membrane of low nominal MW retention (NMWR, 5 kDa) was repetitively used for separation of fluorescent and non-fluorescent species. Thirty ultrafiltrates and the final retentate R were obtained. Fluorescence maxima of separate ultrafiltrates were different and non-monotonously changed in the range of 475-505 nm. Fluorescence maxima of less than 490 nm were detected only in the four first utrafiltrates. For further physical-chemical analyses all utrafiltrates were combined into a fraction called UFchernozem soil HAs complex. Copyright © 2011 Elsevier B.V. All rights reserved.

Efficient Preparation of Super Antifouling PVDF Ultrafiltration Membrane with One Step Fabricated Zwitterionic Surface.

Science.gov (United States)

Zhao, Xinzhen; He, Chunju

2015-08-19

On the basis of the excellent fouling resistance of zwitterionic materials, the super antifouling polyvinylidene fluoride (PVDF) membrane was efficiently prepared though one-step sulfonation of PVDF and polyaniline blend membrane in situ. The self-doped sulfonated polyaniline (SPANI) was generated as a novel zwitterionic polymer to improve the antifouling property of PVDF ultrafiltration membrane used in sewage treatment. Surface attenuated total reflection Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, surface zeta potential, and water contact angle demonstrated the successful fabrication of zwitterionic interface by convenient sulfonation modification. The static adsorption fouling test showed the quantified adsorption mass of bovine serum albumin (BSA) pollutant on the PVDF/SPANI membrane surface decreases to 3(±2) μg/cm(2), and the water flux recovery ratio (FRR) values were no less than 95% for the three model pollutants of BSA, sodium alginate (SA), and humic acid (HA), which were corresponding hydrophobic, hydrophilic, and natural pollutants in sewage, respectively. This Research Article demonstrated the antifouling advantages of zwitterionic SPANI and aimed to provide a simple method for the large scale preparation of zwitterionic antifouling ultrafiltration membranes.

Pretreatment with ceramic membrane microfiltration in the clarification process of sugarcane juice by ultrafiltration

Directory of Open Access Journals (Sweden)

Priscilla dos Santos Gaschi

2014-04-01

Full Text Available In the present study, the sugar cane juice from COCAFE Mill, was clarified using tubular ceramic membranes (α-Al2O3/TiO2 with pore size of 0.1 and 0.3 µm, and membrane area of 0.005 m2. Experiments were performed in batch with sugar cane juice, in a pilot unit of micro and ultrafiltration using the principle of tangential filtration. The sugar cane juice was settled for one hour and the supernatant was treated by microfiltration. After that, the MF permeate was ultrafiltered. The experiments of micro and ultrafiltration were carried out at 65ºC and 1 bar. The ceramic membranes were able to remove the colloidal particles, producing a limpid permeated juice with color reduction. The clarification process with micro- followed by ultrafiltration produced a good result with an average purity rise of 2.74 units, 99.4% lower turbidity and 44.8% lighter color in the permeate.

[Ultrafiltration versus intravenous diuretics in decompensated heart failure: a meta-analysis of randomized controlled trials].

Science.gov (United States)

Zhao, Yu-liang; Zhang, Ling; Yang, Ying-ying; Tang, Yi; Liu, Fang; Fu, Ping

2013-08-13

To explore whether ultrafiltration is superior to intravenous diuretics in ameliorating fluid overload and preserving renal functions in decompensated heart failure patients. By searching in Pubmed, Cochrane Library, Embase, Springer, WanFang, CQVIP, CNKI and CBM database as well as related Chinese journals, qualified randomized controlled trials (RCTs) were included for meta-analysis by Revman 5.0 and STATA 10.0. Six RCTs were included with 241 patients in ultrafiltration group and 240 patients in intravenous diuretics group. Pooled analyses demonstrated ultrafiltration was superior to intravenous diuretics in the aspects of weight loss (WMD = 1.44 kg, 95%CI:0.33-2.55 kg, P = 0.01) and fluid removal (WMD = 1.23 kg, 95%CI:0.63-1.82 kg, P diuretics in mitigating fluid overload. No intergroup difference was observed in renal function preservation, mortality or rehospitalization.

Physicochemical and Microbiological Properties of Yogurt-cheese Manufactured with Ultrafiltrated Cow's Milk and Soy Milk Blends

Science.gov (United States)

Lee, Na-Kyoung; Mok, Bo Ram; Jeewanthi, Renda Kankanamge Chaturika; Yoon, Yoh Chang; Paik, Hyun-Dong

2015-01-01

The objective of this study was to develop yogurt-cheese using cow’s milk, ultrafiltrated cow’s milk, and soy milk. The addition of soy milk and ultrafiltrated milk increased the amount of protein in the yogurt-cheese. Yogurt-cheeses were made using cheese base using 10% and 20% soy milk with raw and ultrafiltrated cow’s milk, and stored at 4℃ during 2 wk. The yield of yogurt-cheeses made with added soy milk was decreased and the cutting point was delayed compared to yogurt-cheese made without soy milk. Yogurt-cheese made using ultrafiltrated cow’s milk showed the highest yield. However, yogurt-cheese made with added soy milk had higher protein content and titratable acidity than yogurt-cheese made using raw and ultrafiltrated cow’s milk. Fat and lactose contents in the yogurt-cheese made with added soy milk were lower. Yogurt-cheeses made with added soy milk contained several soy protein bands corresponding to the sizes of α2-, β-, and κ-casein band. Yogurt-cheese made with added soy milk had similar elasticity to yogurt-cheese made without soy milk but had lower cohesiveness. There was no significant difference in the number of lactic acid bacteria in the different cheeses, as all had over 8.0 Log CFU/g. Considering these data and the fact that proteins and fats of vegetable origin with high biological value were observed as well as unsaturated fats, yogurt-cheese made with added soy milk can be considered to be a functional food. PMID:26761829

Preparation of hydrophilic and antifouling polysulfone ultrafiltration membrane derived from phenolphthalin by copolymerization method

International Nuclear Information System (INIS)

Liu, Zhixiao; Mi, Zhiming; Chen, Chunhai; Zhou, Hongwei; Zhao, Xiaogang; Wang, Daming

2017-01-01

Graphical abstract: The mechanisms fouling and cleaning process of PSF-COOH membranes (A) the content of carboxyl less than 80%. (B) the content of carboxyl at 80%, 100%. - Highlights: • Phenolphthalin (PPL) containing carboxyl was successfully introduced into the molecule backbone of polysulfone (PSF). • A series of PSF-COOH copolymers with different carboxylation degree was synthesized and prepared as ultrafiltration membranes. • The introduction of PPL significantly improved the hydrophilicity, permeation flux and antifouling property of membranes. • This method is valuable for large-scale industrial production of hydrophilic membrane material. - Abstract: In this task, carboxylated polysulfone (PSF-COOH) was achieved by introducing the monomer of phenolphthalin (PPL) containing carboxyl to the molecule backbone of polysulfone (PSF). And a series of PSF-COOH copolymers with different carboxylation degree was synthesized by adjusting the molar (%) of bisphenol A (BPA) and PPL in direct copolymerization method and was prepared as PSF-COOH ultrafiltration membranes via phase separation method. The effect of PPL molar (%) in copolymers on the morphology, hydrophilicity, permeation flux, antifouling and mechanical properties of membranes was investigated by scanning electron microscope (SEM), atomic force microscope (AFM), water contact angle, ultrafiltration experiments and universal testing machine, respectively. The results showed that with the increased carboxyl content in membranes, the hydrophilicity, permeation fluxes and antifouling properties of membranes gradually increased. When the molar (%) of PPL to BPA was 100:0, the membrane exhibited the highest pure water flux (329.6 L/m"2 h) and the maximum flux recovery rate (92.5%). When the content of carboxyl in the membrane was 80% or more, after three cycles of BSA solution (1 g/L) filtration, the flux recovery rate was basically constant or showed a slightly increase. Thus, it can achieve the goal of

Preparation of hydrophilic and antifouling polysulfone ultrafiltration membrane derived from phenolphthalin by copolymerization method

Energy Technology Data Exchange (ETDEWEB)

Liu, Zhixiao; Mi, Zhiming; Chen, Chunhai; Zhou, Hongwei; Zhao, Xiaogang; Wang, Daming, E-mail: wangdaming@jlu.edu.cn

2017-04-15

Graphical abstract: The mechanisms fouling and cleaning process of PSF-COOH membranes (A) the content of carboxyl less than 80%. (B) the content of carboxyl at 80%, 100%. - Highlights: • Phenolphthalin (PPL) containing carboxyl was successfully introduced into the molecule backbone of polysulfone (PSF). • A series of PSF-COOH copolymers with different carboxylation degree was synthesized and prepared as ultrafiltration membranes. • The introduction of PPL significantly improved the hydrophilicity, permeation flux and antifouling property of membranes. • This method is valuable for large-scale industrial production of hydrophilic membrane material. - Abstract: In this task, carboxylated polysulfone (PSF-COOH) was achieved by introducing the monomer of phenolphthalin (PPL) containing carboxyl to the molecule backbone of polysulfone (PSF). And a series of PSF-COOH copolymers with different carboxylation degree was synthesized by adjusting the molar (%) of bisphenol A (BPA) and PPL in direct copolymerization method and was prepared as PSF-COOH ultrafiltration membranes via phase separation method. The effect of PPL molar (%) in copolymers on the morphology, hydrophilicity, permeation flux, antifouling and mechanical properties of membranes was investigated by scanning electron microscope (SEM), atomic force microscope (AFM), water contact angle, ultrafiltration experiments and universal testing machine, respectively. The results showed that with the increased carboxyl content in membranes, the hydrophilicity, permeation fluxes and antifouling properties of membranes gradually increased. When the molar (%) of PPL to BPA was 100:0, the membrane exhibited the highest pure water flux (329.6 L/m{sup 2} h) and the maximum flux recovery rate (92.5%). When the content of carboxyl in the membrane was 80% or more, after three cycles of BSA solution (1 g/L) filtration, the flux recovery rate was basically constant or showed a slightly increase. Thus, it can achieve the

Mass transfer in corrugated-plate membrane modules. II. Ultrafiltration experiments

NARCIS (Netherlands)

van der Waal, M.J.; Stevanovic, S.; Racz, I.G.

1989-01-01

The application of corrugations as turbulence promoters in membrane filtration was studied. In ultrafiltration experiments with polysulfone membranes using Dextran T70 as solute, it was found that the corrugations result in reduced energy consumption or pressure drop compared with flat membranes at

Comparison of ultrafiltration and dissolved air flotation efficiencies in industrial units during the papermaking process

OpenAIRE

Monte Lara, Concepción; Ordóñez Sanz, Ruth; Hermosilla Redondo, Daphne; Sánchez González, Mónica; Blanco Suárez, Ángeles

2011-01-01

The efficiency of an ultrafiltration unit has been studied and compared with a dissolved air flotation system to get water with a suited quality to be reused in the process. The study was done at a paper mill producing light weight coated paper and newsprint paper from 100% recovered paper. Efficiency was analysed by removal of turbidity, cationic demand, total and dissolved chemical oxygen demand, hardness, sulphates and microstickies. Moreover, the performance of the ultrafiltration unit an...

Plasma deposition of silver nanoparticles on ultrafiltration membranes: antibacterial and anti-biofouling properties.

Science.gov (United States)

Cruz, Mercedes Cecilia; Ruano, Gustavo; Wolf, Marcus; Hecker, Dominic; Vidaurre, Elza Castro; Schmittgens, Ralph; Rajal, Verónica Beatriz

2015-02-01

A novel and versatile plasma reactor was used to modify Polyethersulphone commercial membranes. The equipment was applied to: i) functionalize the membranes with low-temperature plasmas, ii) deposit a film of poly(methyl methacrylate) (PMMA) by Plasma Enhanced Chemical Vapor Deposition (PECVD) and, iii) deposit silver nanoparticles (SNP) by Gas Flow Sputtering. Each modification process was performed in the same reactor consecutively, without exposure of the membranes to atmospheric air. Scanning electron microscopy and transmission electron microscopy were used to characterize the particles and modified membranes. SNP are evenly distributed on the membrane surface. Particle fixation and transport inside membranes were assessed before- and after-washing assays by X-ray photoelectron spectroscopy depth profiling analysis. PMMA addition improved SNP fixation. Plasma-treated membranes showed higher hydrophilicity. Anti-biofouling activity was successfully achieved against Gram-positive ( Enterococcus faecalis ) and -negative ( Salmonella Typhimurium) bacteria. Therefore, disinfection by ultrafiltration showed substantial resistance to biofouling. The post-synthesis functionalization process developed provides a more efficient fabrication route for anti-biofouling and anti-bacterial membranes used in the water treatment field. To the best of our knowledge, this is the first report of a gas phase condensation process combined with a PECVD procedure in order to deposit SNP on commercial membranes to inhibit biofouling formation.

Energy rationalization in the dairy industry through the use of ultrafiltration

Energy Technology Data Exchange (ETDEWEB)

Faletti, L; Peri, C

1987-02-01

This study is one of several made by Italian universities on behalf of ENEL to razionalize the energy demand pattern of some industrial branches and identify, among the various solutions, those that might bring about primary energy saving through the use of electricity. Specifically, this study was undertaken to verify the applicability of certain diaphragm separation technologies such as ultrafiltration in Italy, and to assess their energy-efficiency in terms of primary energy. Research carried out on this subject and the industrial experience of the last years point to the possibility of using ultrafiltration in the manufacture of typical soft cheese in direct competition with conventional technologies. The expected benefits of greater yield and energy saving are of great national economic relevance, since Italy imports both the raw material (milk) and energy resources.

Summary of the ultrafiltration, reverse osmosis, and adsorbents project

International Nuclear Information System (INIS)

Colvin, C.M.; Roberts, R.C.; Williams, M.K.

1983-01-01

The design for a medium-size (40 gal/min) ultrafiltration (UF) membrane unit includes a schematic diagram, capital and operating costs, a list and discussion of the radioisotopes tested and the results achieved, operating parameters, and characteristics of the available membrane configurations. The plant design for a reverse osmosis (RO) membrane unit includes a conceptual diagram, specifications for a RO unit producing 40 gal/min of permeated product, a list of radioisotopes tested on RO units and the rejections achieved, a discussion of the principal of RO, a discussion of the upper limits of cation and anion concentrations (there are no lower limits), a discussion of membrane configurations and porosities, a discussion of factors affecting membranes, a section on calculating the membrane area needed for a particular application, and capital and operating cost calculations. The design for an ion-exchange pilot plant includes a schematic diagram; flow, resin, and column specifications; impurity limits; and operating and capital costs. A short theoretical discussion and process description are also included. The design retains flexibility so that application to a specific stream can be determined

An analysis of ultrafiltration applications for the oilsands

Energy Technology Data Exchange (ETDEWEB)

Pease, S. [Zenon Environmental Inc., Oakville, ON (Canada)

2006-07-01

This presentation examined ultrafiltration technologies in oil sands applications. The Athabasca region has limited water supplies, and regulatory standards regarding waterborne pathogens and disinfectant by-products are increasing. Membrane technologies are now rapidly replacing conventional water filtration technologies as they provide a more reliable means of filtration and use minimal amounts of chemicals. Membrane technologies are capable of removing 99.9 per cent of all Giardia, Cryptosporidium and viral agents from water samples, as well as various metals. ZeeWeed membrane filtration systems use a backpulse system to filter water in combination with a permeation system. Enhanced coagulation systems are used to remove colour, taste, and odours, as well as manganese and iron. The systems have been tested with Athabasca River samples, and are currently being used at several oil sands processing plants. It was concluded that ZeeWeed membrane systems are able to treat difficult waters with high pathogen and metals contents. tabs., figs.

Purification of Drug Loaded PLGA Nanoparticles Prepared by Emulsification Solvent Evaporation Using Stirred Cell Ultrafiltration Technique.

Science.gov (United States)

Paswan, Suresh K; Saini, T R

2017-12-01

The emulsifiers in an exceedingly higher level are used in the preparation of drug loaded polymeric nanoparticles prepared by emulsification solvent evaporation method. This creates great problem to the formulator due to their serious toxicities when it is to be administered by parenteral route. The final product is therefore required to be freed from the used surfactants by the conventional purification techniques which is a cumbersome job. The solvent resistant stirred cell ultrafiltration unit (Millipore) was used in this study using polyethersulfone ultrafiltration membrane (Biomax®) having pore size of NMWL 300 KDa as the membrane filter. The purification efficiency of this technique was compared with the conventional centrifugation technique. The flow rate of ultrafiltration was optimized for removal of surfactant (polyvinyl alcohol) impurities to the acceptable levels in 1-3.5 h from the nanoparticle dispersion of tamoxifen prepared by emulsification solvent evaporation method. The present investigations demonstrate the application of solvent resistant stirred cell ultrafiltration technique for removal of toxic impurities of surfactant (PVA) from the polymeric drug nanoparticles (tamoxifen) prepared by emulsification solvent evaporation method. This technique offers added benefit of producing more concentrated nanoparticles dispersion without causing significant particle size growth which is observed in other purification techniques, e.g., centrifugation and ultracentrifugation.

Residual blood processing by centrifugation, cell salvage or ultrafiltration in cardiac surgery: effects on clinical hemostatic and ex-vivo rheological parameters.

Science.gov (United States)

Vonk, Alexander B; Muntajit, Warayouth; Bhagirath, Pranav; van Barneveld, Laurentius J; Romijn, Johannes W; de Vroege, Roel; Boer, Christa

2012-10-01

The study compared the effects of three blood concentration techniques after cardiopulmonary bypass on clinical hemostatic and ex-vivo rheological parameters. Residual blood of patients undergoing elective cardiac surgery was processed by centrifugation, cell salvage or ultrafiltration, and retransfused (n = 17 per group). Study parameters included blood loss, (free) hemoglobin, hematocrit, fibrinogen and erythrocyte aggregation, deformability and 2,3-diphosphoglycerate content. Patient characteristics were similar between groups. Ultrafiltration was associated with the highest weight of the transfusion bag [649 ± 261 vs. 320 ± 134 g (centrifugation) and 391 ± 158 g (cell salvage); P levels in the transfusion bag. Retransfusion of cell saver blood induced the largest gain in postoperative patient hemoglobin levels when compared to centrifugation and ultrafiltration, and was associated with the largest increase in 2,3-diphosphoglycerate when compared to ultrafiltration (Δ2,3-diphosphoglycerate 1.34 ± 1.92 vs. -0.77 ± 1.56 mmol/l; P = 0.03). Cell salvage is superior with respect to postoperative hemoglobin gain and washout of free hemoglobin when compared to centrifugation or ultrafiltration.

Improved antifouling performance of ultrafiltration membrane via preparing novel zwitterionic polyimide

Science.gov (United States)

Huang, Haitao; Yu, Jiayu; Guo, Hanxiang; Shen, Yibo; Yang, Fan; Wang, Han; Liu, Rong; Liu, Yang

2018-01-01

On the basis of the outstanding fouling resistance of zwitterionic polymers, an antifouling ultrafiltration membrane was fabricated through phase inversion induced by immersion precipitation method, directly using the novel zwitterionic polyimide (Z-PI), which was synthesized via a two-step procedure including polycondensation and quaternary amination reaction, as membrane material. The chemical structure and composition of the obtained polymer were confirmed by using FTIR, 1H NMR and XPS analysis, and its thermal stability was thoroughly characterized by TGA measurement, respectively. The introduction of zwitterionic groups into polyimide could effectively increase membrane pore size, porosity and wettability, and convert the membrane surface from hydrophobic to highly hydrophilic. As a result, Z-PI membrane displayed significantly improved water permeability compared with that of the reference polyimide (R-PI) membrane without having an obvious compromise in protein rejection. According to the static adsorption and dynamic cycle ultrafiltration experiments of bovine serum albumin (BSA) solution, Z-PI membrane exhibited better fouling resistant ability, especially irreversible fouling resistant ability, suggesting superior antifouling property and long-term performance stability. Moreover, Z-PI membrane had a water flux recovery ratio of 93.7% after three cycle of BSA solution filtration, whereas only about 68.5% was obtained for the control R-PI membrane. These findings demonstrated the advantages of Z-PI membrane material and aimed to provide a facile and scalable method for the large-scale preparation of low fouling ultrafiltration membranes for potential applications.

Processing used nuclear fuel with nanoscale control of uranium and ultrafiltration

Energy Technology Data Exchange (ETDEWEB)

Wylie, Ernest M.; Peruski, Kathryn M.; Prizio, Sarah E. [Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN 46556 (United States); Bridges, Andrea N.A.; Rudisill, Tracy S.; Hobbs, David T. [Savannah River National Laboratory, Aiken, SC 29808 (United States); Phillip, William A. [Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, IN 46556 (United States); Burns, Peter C., E-mail: pburns@nd.edu [Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN 46556 (United States); Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556 (United States)

2016-05-15

Current separation and purification technologies utilized in the nuclear fuel cycle rely primarily on liquid–liquid extraction and ion-exchange processes. Here, we report a laboratory-scale aqueous process that demonstrates nanoscale control for the recovery of uranium from simulated used nuclear fuel (SIMFUEL). The selective, hydrogen peroxide induced oxidative dissolution of SIMFUEL material results in the rapid assembly of persistent uranyl peroxide nanocluster species that can be separated and recovered at moderate to high yield from other process-soluble constituents using sequestration-assisted ultrafiltration. Implementation of size-selective physical processes like filtration could results in an overall simplification of nuclear fuel cycle technology, improving the environmental consequences of nuclear energy and reducing costs of processing. - Highlights: • Nanoscale control in irradiated fuel reprocessing. • Ultrafiltration to recover uranyl cage clusters. • Alternative to solvent extraction for uranium purification.

Deposition of thin ultrafiltration membranes on commercial SiC microfiltration tubes

DEFF Research Database (Denmark)

Facciotti, Marco; Boffa, Vittorio; Magnacca, Giuliana

2014-01-01

Porous SiC based materials present high mechanical, chemical and thermal robustness, and thus have been largely applied to water-filtration technologies. In this study, commercial SiC microfiltration tubes with nominal pore size of 0.04 m were used as carrier for depositing thin aluminium oxide....... After 5 times coating, a 5.6 µm thick γ-Al2O3 layer was obtained. This membrane shows retention of ~75% for polyethylene glycol molecules with Mn of 8 and 35 kDa, indicating that, despite their intrinsic surface roughness, commercial SiC microfiltration tubes can be applied as carrier for thin...... ultrafiltration membranes. This work also indicates that an improvement of the commercial SiC support surface smoothness may greatly enhance permeance and selectivity of Υ-Al2O3 ultrafiltration membranes by allowing the deposition of thinner defect-free layers....

Modified performance test of vented lead acid batteries for stationary applications

International Nuclear Information System (INIS)

Uhlir, K.W.; Fletcher, R.J.

1995-01-01

The concept of a modified performance test for vented lead acid batteries in stationary applications has been developed by the IEEE Battery Working Group. The modified performance test is defined as a test in the ''as found'' condition of the battery capacity and its ability to provide a high rate, short duration load (usually the highest rate of the duty cycle) that will confirm the battery's ability to meet the critical period of the load duty cycle, in addition to determining its percentage of rated capacity. This paper will begin by reviewing performance and service test requirements and concerns associated with both types of tests. The paper will then discuss the rationale for developing a modified performance test along with the benefits that can be derived from performing a modified performance test in lieu of a capacity test and/or a service test. The paper will conclude with an example on how to apply a modified performance test and test acceptance criteria

The in-process removal of sterol glycosides by ultrafiltration in biodiesel production

Directory of Open Access Journals (Sweden)

André Y. Tremblay

2017-03-01

Full Text Available Minor components found in biodiesel can affect its stability and cold flow properties. Without extensive post treatments, trace compounds such as sterol glycosides (SG can remain at unacceptable levels in finished biodiesel fuels. This study proposes to remove SG from reacted Fatty Acid Methyl Ester (FAME mixtures using ultrafiltration. Degummed soybean oil was transesterified using methanol and a catalyst (sodium methoxide. The mixtures were immediately ultrafiltered after the reaction and the FAMEs from the retentate and permeate were analyzed for SG. The highest separation for SG (86 % was obtained when the reaction conditions were 0.7 wt.% catalyst and 4:1 MeOH:Oil ratio. The lowest separation (0% was observed at 0.3 wt.% catalyst and 4:1 MeOH:Oil ratio. The higher separations were explained by the deprotonation of the hydroxyl groups on SG. This decreased the solubility of SG in the reacted FAME phase. The separation was lowest, when unreacted oil along with monoacylglycerides (MG and diacylglycerides (DG solubilized SG in the reacted mixture. The separation was also low when high methanol to oil ratios were used in the transesterification. The lowest concentration of SG measured in FAMEs treated by ultrafiltration was 3.4 ppm. The results indicate that ultrafiltration is an effective method to remove SG from soybean FAMEs.

Removal of phenol from synthetic waste water using Gemini micellar-enhanced ultrafiltration (GMEUF)

Energy Technology Data Exchange (ETDEWEB)

Zhang, Wenxiang [MOE Key Laboratory of Regional Energy and Environmental Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China); Huang, Guohe, E-mail: huang@iseis.org [MOE Key Laboratory of Regional Energy and Environmental Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China); Wei, Jia [Faculty of Engineering and Applied Science, University of Regina, Regina, Saskatchewan, Canada S4S 0A2 (Canada); Li, Huiqin; Zheng, Rubing; Zhou, Ya [MOE Key Laboratory of Regional Energy and Environmental Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China)

2012-10-15

Highlights: Black-Right-Pointing-Pointer Gemini surfactant micellar enhanced ultrafiltration was used to remove phenol. Black-Right-Pointing-Pointer The effect of different hydrophilic head groups of surfactant was analyzed. Black-Right-Pointing-Pointer SEM, ATR-FTIR and mercury porosimeter were applied to elucidate membrane fouling. Black-Right-Pointing-Pointer Gemini surfactant had superior performance in comparing with conventional surfactant. - Abstract: Comprehensive studies were conducted on the phenol wastewater ultrafiltration (UF) with the help of various concentrations of cationic Gemini surfactant (N1-dodecyl-N1,N1,N2,N2-tetramethyl-N2-octylethane-1,2-diaminium bromide, CG), conventional cationic surfactant (dodecyl trimethyl ammonium bromide, DTAB), anionic surfactant (sodium dodecyl sulfate, SDS) and nonionic surfactant ((dodecyloxy)polyethoxyethanol, Brij35). A flat sheet module with polyethersulfone (PES) membrane was employed in this investigation. The effects of feed concentration (phenol and surfactant) on the retention of phenol and surfactant, permeate flux and membrane fouling by micelles were evaluated. The distribution coefficient (D), the loading of the micelles (L{sub m}) and the equilibrium distribution constant (K) were also utilized to estimate the micellar-enhanced ultrafiltration ability for phenol. Scanning electron microscope (SEM), Fourier transform infrared spectrometer with attenuated total reflectance accessory (ATR-FTIR) and mercury porosimeter were applied to analyze membrane surface morphology, membrane material characteristics and membrane fouling for the original and fouled membranes. Based on the above analysis, the performance of the selected Gemini surfactant was proved superior in the following aspects: retention of phenol/surfactant (peak value is 95.8% for phenol retention), permeate flux and membrane fouling with respect to other conventional surfactants possessing equal alkyl chain length. These results demonstrated

46 CFR 56.97-30 - Hydrostatic tests (modifies 137.4).

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Hydrostatic tests (modifies 137.4). 56.97-30 Section 56... SYSTEMS AND APPURTENANCES Pressure Tests § 56.97-30 Hydrostatic tests (modifies 137.4). (a) Provision of... system is filling. (b) Test medium and test temperature. (1) Water will be used for a hydrostatic leak...

Crossflow ultrafiltration of raw municipal wastewater : Investigations using PVDF tubular membranes

NARCIS (Netherlands)

Ravazzini, A.M.

2008-01-01

In the usual wastewater treatment schemes the application of membranes follows a biological process. However, ultrafiltration of untreated wastewater produces permeate free of particles and bacteria in one single step and could represent the starting point for new water-reuse concepts. This thesis

EFFICIENCY OF ULTRAFILTRATION CERAMIC MEMBRANES FOR TOXIC ELEMENTS REMOVAL FROM WASTEWATERS

Directory of Open Access Journals (Sweden)

S. Alami Younssi

2010-07-01

Full Text Available The preparation and characterization of porous ceramics multilayer ultrafiltration membrane is described. The first step consisted to prepare high-quality macroporous support in Moroccan clay. The choice of this material is based on its natural abundance and thermal stability.The microporous interlayer was then prepared by slip casting from zirconia commercial powders and finally the active UF toplayers was obtained by sol-gel route using ZnAl2O4 and TiO2 mixed sols. The performance of ultrafiltration membrane (TiO2 (50�20– ZnAl2O4 (50� was evaluated by pores diameter, water flux, thickness and molecular weight cut off (MWCO. The water permeability measured for this composite membrane is 9.42 L/(m2•h•bar, the thickness is less than 700 nm, the pore diameter is centered near 5 nm and the MWCO was about 4500 Da.

Concentration of infectious aquatic rhabdoviruses from freshwater and seawater using ultrafiltration.

Science.gov (United States)

Grant, Amelia A M; Jakob, Eva; Richard, Jon; Garver, Kyle A

2011-12-01

Infectious hematopoietic necrosis virus (IHNV), viral hemorrhagic septicemia virus, and spring viremia of carp virus were concentrated and detected from freshwater and seawater samples by using hollow-fiber ultrafiltration. Within 60 min, virus in a 50-L freshwater or saltwater sample was concentrated more than 70-fold, and virus retention efficiencies were consistently greater than 88%. Retention efficiency was highly dependent upon concentrations of column blocking and sample stabilization solutions. A large column with a surface area of 1.15 m2 and a filtration capacity of 5-200 L exhibited optimal viral retention when blocked with 2% fetal bovine serum (FBS) and when the samples were supplemented with 0.1% FBS. Conversely, a small column with 100-fold less surface area and a filtering capacity of 0.5-2.0 L was optimized when blocked with 1% FBS and when the samples were supplemented with 0.1% FBS. The optimized ultrafiltration procedure was further validated with water from a tank that contained IHNV-exposed juvenile sockeye salmon Oncorhynchus nerka, resulting in an average virus retention efficiency of 91.6 +/- 4.1% (mean +/- SE). Virus quantification of concentrated samples demonstrated that IHNV shedding in sockeye salmon preceded mortality; shedding of the virus was observed to increase significantly as early as 7 d postchallenge and peaked at day 14, when virus levels reached 4.87 x 10(3) plaque-forming units/mL. We conclude that ultrafiltration is a reliable and effective method for concentrating viable aquatic rhabdoviruses from large volumes of water and has application for the analysis of environmental water samples.

Fouling Characteristics of Dissolved Organic Matter in Papermaking Process Water on Polyethersulfone Ultrafiltration Membranes

Directory of Open Access Journals (Sweden)

Wenpeng Su

2015-07-01

Full Text Available In the papermaking industry, closure of process water (whitewater circuits has been used to reduce fresh water consumption. Membrane separation technology has potential for use in treating process water for recirculation. The purpose of this study was to reveal the fouling characteristics of a polyethersulfone (PES ultrafiltration membrane caused by dissolved organic matter (DOM in process water. Ultrafiltration membranes (UF and DAX ion exchange resins were applied to characterize the molecular weight (MW and hydrophilicity distribution of DOM. The interactions between various fractions of DOM and a PES ultrafiltration membrane were investigated. The membrane fouling characteristics were elucidated by examining the filtration resistances and linearized Herman’s blocking models. The results demonstrated that the membrane was fouled significantly by much of the MW distribution. The membrane was fouled more significantly by the low MW fraction rather than the high MW fraction. The filtration resistances and the fitted equation of Hermia’s laws indicated that hydrophilic organics were the main foulants. The hydrophilic organics partially block the membrane pores and form intermediate blocking, reducing the effective filtration area, while the hydrophobic organics form a gel layer or cake on the surface of the membrane.

Polyethersulfone-based ultrafiltration hollow fibre membrane for drinking water treatment systems

Science.gov (United States)

Chew, Chun Ming; Ng, K. M. David; Ooi, H. H. Richard

2017-12-01

Conventional media/sand filtration has been the mainstream water treatment process for most municipal water treatment plants in Malaysia. Filtrate qualities of conventional media/sand filtration are very much dependent on the coagulation-flocculation process prior to filtration and might be as high as 5 NTU. However, the demands for better quality of drinking water through public piped-water supply systems are growing. Polymeric ultrafiltration (UF) hollow fibre membrane made from modified polyethersulfone (PES) material is highly hydrophilic with high tensile strength and produces excellent quality filtrate of below 0.3 NTU in turbidity. This advanced membrane filtration material is also chemical resistance which allows a typical lifespan of 5 years. Comparisons between the conventional media/sand filtration and PES-based UF systems are carried out in this paper. UF has been considered as the emerging technology in municipal drinking water treatment plants due to its consistency in producing high quality filtrates even without the coagulation-flocculation process. The decreasing cost of PES-based membrane due to mass production and competitive pricing by manufacturers has made the UF technology affordable for industrial-scale water treatment plants.

Research on the experiment of reservoir water treatment applying ultrafiltration membrane technology of different processes.

Science.gov (United States)

Zhang, Liyong; Zhang, Penghui; Wang, Meng; Yang, Kai; Liu, Junliang

2016-09-01

The processes and effects of coagulation-ultrafiltration (C-UF) and coagulation sedimentation-ultrafiltration (CS-UF) process used in the treatment of Dalangdian Reservoir water were compared. The experiment data indicated that 99% of turbidity removal and basically 100% of microorganism and algae removal were achieved in both C-UF and CS-UF process. The organic removal effect of CS-UF? process was slightly better than C-UF process. However, the organic removal effect under different processes was not obvious due to limitation of ultrafiltration membrane aperture. Polyaluminium chloride was taken as a coagulant in water plant. The aluminum ion removal result revealed that coagulant dosage was effectively saved by using membrane technology during megathermal high algae laden period. Within the range of certain reagent concentration and soaking time, air-water backwashing of every filtration cycle of membrane was conducted to effectively reduce membrane pollution. Besides, maintenance cleaning was conducted every 60 min. whether or not restorative cleaning was conducted depends on the pollution extent. After cleaning, recovery of membrane filtration effect was obvious.

F and H Area Effluent Treatment Facility (F/H ETF): ultrafiltration and hyperfiltration systems testing at Carre, Inc. with simulated F and H area effluents

International Nuclear Information System (INIS)

Ryan, J.P.

1984-01-01

The F and H Area Effluent Treatment Facility is essentially a four-stage process that will decontaminate the waste water that is currently being discharged to seepage basins in the Separations Areas. The stages include pretreatment, reverse osmosis, ion exchange, and evaporation. A series of tests were performed at Carre, Inc. (Seneca, SC) from March 5 through March 13, to determine the usefulness of ultrafiltration (UF) in the pretreatment stage of the ETF. The results of that testing program indicate that UF would be an excellent means of removing entrained activity from the 200 Area process effluents. Hyperfiltration (HF) was also tested as a means of providing an improved concentration factor from the reverse osmosis stage. The results show that the membranes that were tested would not reject salt well enough at high salt concentrations to be useful in the final reverse osmosis stage. However, there are several membranes which are commercially available that would provide the needed rejection if they could be applied (dynamically) on the Carre support structure. This avenue is still being explored, as theoretically, it could eliminate the need for the F/H ETF evaporator

Decolourisations and biodegradations of model azo dye solutions using a sequence batch reactor, followed by ultrafiltration

DEFF Research Database (Denmark)

Korenak, J.; Ploder, J.; Trček, J.

2018-01-01

RNA gene and ITS1-5.8S rDNA-ITS2 sequence analysis, respectively. Serratia marcescens and Klebsiella oxytoca were the most common bacteria with the highest number present during the aerobic and anaerobic phases of the bioprocess. In addition, a high number of Elizabethkingia miricola, Morganella morganii......, Comamonas testosteroni, Trichosporon sp. and Galactomyces sp. were detected. Taken together, our results demonstrated that the sequencing batch reactor system combined with ultrafiltration is an efficient technique for treatment of wastewater containing azo dye. Moreover, the ultrafiltration effectively...

Enhanced biofouling resistance of polyethersulfone membrane surface modified with capsaicin derivative and itaconic acid

Energy Technology Data Exchange (ETDEWEB)

Wang, Jian [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100 (China); College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100 (China); Gao, Xueli, E-mail: gxl_ouc@126.com [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100 (China); College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100 (China); Wang, Qun; Sun, Haijing; Wang, Xiaojuan [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100 (China); College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100 (China); Gao, Congjie, E-mail: gaocjie@ouc.edu.cn [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100 (China); College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100 (China)

2015-11-30

Graphical abstract: - Highlights: • PES membrane was modified with a capsaicin derivative. • UV-assisted graft polymerization was carried out on membrane surface. • The capsaicin derivative modified membrane shows better antibiofouling property. - Abstract: The culprit of biofouling is the reproduction of viable microorganisms on the membrane surface. Recently, functionalization of membrane surface with natural antibacterial agents has drawn great attention. This work presents the fabrication of antibiofouling polyethersulfone (PES) ultrafiltration (UF) membranes by UV-assisted photo grafting of capsaicin derivative (N-(4-hydroxy-3-methoxy-benzyl)-acrylamide, HMBA) and itaconic acid (IA) on the surface of PES membrane. Results of FTIR-ATR, water static contact angle (WSCA) and atomic force microscopy (AFM) analysis confirmed the successful grafting of HMBA and IA on the membrane surface. We investigated the antifouling and antibacterial properties of these membranes using BSA and Escherichia coli as the test model, respectively. During a 150-min test, the modified membranes show much lower flux decline (42.7% for PES-g-1H0I, 22.2% for PES-g-1H1I and 7.7% for PES-g-1H5I) when compared with the pristine membrane (flux declined by 77%). The modified membranes exhibit excellent antibacterial activity (nearly 100%) when UV irradiation time was 6 min. The morphological study suggested that the E. coli on the pristine membrane showed a regular and smooth surface while that on the modified membrane was disrupted, which validated the antibacterial activity of the modified membranes.

Enhanced biofouling resistance of polyethersulfone membrane surface modified with capsaicin derivative and itaconic acid

International Nuclear Information System (INIS)

Wang, Jian; Gao, Xueli; Wang, Qun; Sun, Haijing; Wang, Xiaojuan; Gao, Congjie

2015-01-01

Graphical abstract: - Highlights: • PES membrane was modified with a capsaicin derivative. • UV-assisted graft polymerization was carried out on membrane surface. • The capsaicin derivative modified membrane shows better antibiofouling property. - Abstract: The culprit of biofouling is the reproduction of viable microorganisms on the membrane surface. Recently, functionalization of membrane surface with natural antibacterial agents has drawn great attention. This work presents the fabrication of antibiofouling polyethersulfone (PES) ultrafiltration (UF) membranes by UV-assisted photo grafting of capsaicin derivative (N-(4-hydroxy-3-methoxy-benzyl)-acrylamide, HMBA) and itaconic acid (IA) on the surface of PES membrane. Results of FTIR-ATR, water static contact angle (WSCA) and atomic force microscopy (AFM) analysis confirmed the successful grafting of HMBA and IA on the membrane surface. We investigated the antifouling and antibacterial properties of these membranes using BSA and Escherichia coli as the test model, respectively. During a 150-min test, the modified membranes show much lower flux decline (42.7% for PES-g-1H0I, 22.2% for PES-g-1H1I and 7.7% for PES-g-1H5I) when compared with the pristine membrane (flux declined by 77%). The modified membranes exhibit excellent antibacterial activity (nearly 100%) when UV irradiation time was 6 min. The morphological study suggested that the E. coli on the pristine membrane showed a regular and smooth surface while that on the modified membrane was disrupted, which validated the antibacterial activity of the modified membranes.

Flux limitation in ultrafiltration: Osmotic pressure model and gel layer model

NARCIS (Netherlands)

Wijmans, J.G.; Nakao, S.; Smolders, C.A.

1984-01-01

The characteristic permeate flux behaviour in ultrafiltration, i.e., the existence of a limiting flux which is independent of applied pressure and membrane resistance and a linear plot of the limiting flux versus the logarithm of the feed concentration, is explained by the osmotic pressure model. In

Vascular endothelial growth factor receptor-3 is a novel target to improve net ultrafiltration in methylglyoxal-induced peritoneal injury.

Science.gov (United States)

Terabayashi, Takeshi; Ito, Yasuhiko; Mizuno, Masashi; Suzuki, Yasuhiro; Kinashi, Hiroshi; Sakata, Fumiko; Tomita, Takako; Iguchi, Daiki; Tawada, Mitsuhiro; Nishio, Ryosuke; Maruyama, Shoichi; Imai, Enyu; Matsuo, Seiichi; Takei, Yoshifumi

2015-09-01

Appropriate fluid balance is important for good clinical outcomes and survival in patients on peritoneal dialysis. We recently reported that lymphangiogenesis associated with fibrosis developed in the peritoneal cavity via the transforming growth factor-β1-vascular endothelial growth factor-C (VEGF-C) pathway. We investigated whether VEGF receptor-3 (VEGFR-3), the receptor for VEGF-C and -D, might be a new target to improve net ultrafiltration by using adenovirus-expressing soluble VEGFR-3 (Adeno-sVEGFR-3) in rodent models of peritoneal injury induced by methylglyoxal (MGO). We demonstrated that lymphangiogenesis developed in these MGO models, especially in the diaphragm, indicating that lymphangiogenesis is a common feature in the peritoneal cavity with inflammation and fibrosis. In MGO models, VEGF-D was significantly increased in the diaphragm; however, VEGF-C was not significantly upregulated. Adeno-sVEGFR-3, which was detected on day 50 after administration via tail vein injections, successfully suppressed lymphangiogenesis in the diaphragm and parietal peritoneum in mouse MGO models without significant effects on fibrosis, inflammation, or neoangiogenesis. Drained volume in the peritoneal equilibration test using a 7.5% icodextrin peritoneal dialysis solution (the 7.5% icodextrin peritoneal equilibration test) was improved by Adeno-sVEGFR-3 on day 22 (Ptarget to improve net ultrafiltration by suppressing lymphatic absorption and that the 7.5% icodextrin peritoneal equilibration test is useful for estimation of lymphatic absorption.

Quantification of biomolecules in herring (Clupea harengus) industry processing waters and their recovery using electroflocculation and ultrafiltration

DEFF Research Database (Denmark)

Osman, Ali; Gringer, Nina; Svendsen, Tore

2015-01-01

Four types of herring industry processing waters; refrigerated sea water (RSW), storage water (SW), processing water from cutting (PW) and pre-salting brines (SB) were subjected to chemical characterization and biomolecule recovery using electroflocculation (EF) and ultrafiltration (UF). The high......Four types of herring industry processing waters; refrigerated sea water (RSW), storage water (SW), processing water from cutting (PW) and pre-salting brines (SB) were subjected to chemical characterization and biomolecule recovery using electroflocculation (EF) and ultrafiltration (UF...

Rheological testing of crumb rubber modified bitumen

CSIR Research Space (South Africa)

Mturi, GAJ

2011-08-01

Full Text Available used to analyse crumb rubber modified (CRM) bitumen is that the specified gap setting in the configuration of the DSR between the upper and lower test platens is too small to accommodate crumb rubber particles. DSR testing of CRM bitumen therefore...

Ceramic membrane fouling during ultrafiltration of oil/water emulsions: roles played by stabilization surfactants of oil droplets.

Science.gov (United States)

Lu, Dongwei; Zhang, Tao; Ma, Jun

2015-04-07

Oil/water (O/W) emulsion stabilized by surfactants is the part of oily wastewater that is most difficult to handle. Ceramic membrane ultrafiltration presently is an ideal process to treat O/W emulsions. However, little is known about the fouling mechanism of the ceramic membrane during O/W emulsion treatment. This paper investigated how stabilization surfactants of O/W emulsions influence the irreversible fouling of ceramic membranes during ultrafiltration. An unexpected phenomenon observed was that irreversible fouling was much less when the charge of the stabilization surfactant of O/W emulsions is opposite to the membrane. The less ceramic membrane fouling in this case was proposed to be due to a synergetic steric effect and demulsification effect which prevented the penetration of oil droplets into membrane pores and led to less pore blockage. This proposed mechanism was supported by cross section images of fouled and virgin ceramic membranes taken with scanning electron microscopy, regression results of classical fouling models, and analysis of organic components rejected by the membrane. Furthermore, this mechanism was also verified by the existence of a steric effect and demulsification effect. Our finding suggests that ceramic membrane oppositely charged to the stabilization surfactant should be applied in ultrafiltration of O/W emulsions to alleviate irreversible membrane fouling. It could be a useful rule for ceramic membrane ultrafiltration of oily wastewater.

Ceramic membrane fouling during ultrafiltration of oil/water emulsions: Roles played by stabilization surfactants of oil droplets

KAUST Repository

Lu, Dongwei

2015-04-07

Oil/water (O/W) emulsion stabilized by surfactants is the part of oily wastewater that is most difficult to handle. Ceramic membrane ultrafiltration presently is an ideal process to treat O/W emulsions. However, little is known about the fouling mechanism of the ceramic membrane during O/W emulsion treatment. This paper investigated how stabilization surfactants of O/W emulsions influence the irreversible fouling of ceramic membranes during ultrafiltration. An unexpected phenomenon observed was that irreversible fouling was much less when the charge of the stabilization surfactant of O/W emulsions is opposite to the membrane. The less ceramic membrane fouling in this case was proposed to be due to a synergetic steric effect and demulsification effect which prevented the penetration of oil droplets into membrane pores and led to less pore blockage. This proposed mechanism was supported by cross section images of fouled and virgin ceramic membranes taken with scanning electron microscopy, regression results of classical fouling models, and analysis of organic components rejected by the membrane. Furthermore, this mechanism was also verified by the existence of a steric effect and demulsification effect. Our finding suggests that ceramic membrane oppositely charged to the stabilization surfactant should be applied in ultrafiltration of O/W emulsions to alleviate irreversible membrane fouling. It could be a useful rule for ceramic membrane ultrafiltration of oily wastewater. © 2015 American Chemical Society.

Dual-Functional Ultrafiltration Membrane for Simultaneous Removal of Multiple Pollutants with High Performance.

Science.gov (United States)

Pan, Shunlong; Li, Jiansheng; Noonan, Owen; Fang, Xiaofeng; Wan, Gaojie; Yu, Chengzhong; Wang, Lianjun

2017-05-02

Simultaneous removal of multiple pollutants from aqueous solution with less energy consumption is crucial in water purification. Here, a novel concept of dual-functional ultrafiltration (DFUF) membrane is demonstrated by entrapment of nanostructured adsorbents into the finger-like pores of ultrafiltration (UF) membrane rather than in the membrane matrix in previous reports of blend membranes, resulting in an exceptionally high active content and simultaneous removal of multiple pollutants from water due to the dual functions of rejection and adsorption. As a demonstration, hollow porous Zr(OH) x nanospheres (HPZNs) were immobilized in poly(ether sulfone) (PES) UF membranes through polydopamine coating with a high content of 68.9 wt %. The decontamination capacity of DFUF membranes toward multiple model pollutants (colloidal gold, polyethylene glycol (PEG), Pb(II)) was evaluated against a blend membrane. Compared to the blend membrane, the DFUF membranes showed 2.1-fold increase in the effective treatment volume for the treatment of Pb(II) contaminated water from 100 ppb to below 10 ppb (WHO drinking water standard). Simultaneously, the DFUF membranes effectively removed the colloidal gold and PEG below instrument detection limit, however the blend membrane only achieved 97.6% and 96.8% rejection for colloidal gold and PEG, respectively. Moreover, the DFUF membranes showed negligible leakage of nanoadsorbents during testing; and the membrane can be easily regenerated and reused. This study sheds new light on the design of high performance multifunction membranes for drinking water purification.

Exploration of zwitterionic cellulose acetate antifouling ultrafiltration membrane for bovine serum albumin (BSA) separation.

Science.gov (United States)

Liu, Yang; Huang, Haitao; Huo, Pengfei; Gu, Jiyou

2017-06-01

This study focused on the preparation of a new kind of membrane material, zwitterionic cellulose acetate (ZCA), via a three-step procedure consist of oxidization, Schiff base and quaternary amination reaction, and the fabrication of antifouling ZCA ultrafiltration membrane by the non-solvent-induced phase separation method (NIPS). The morphologies, surface chemical structures and compositions of the obtained CA and ZCA membranes were thoroughly characterized by field emission scanning electron microscopy (FE-SEM) with energy dispersive X-ray (EDX) spectroscopy, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), respectively. Meanwhile, the thermal stability, porosity and average pore size of two investigated membranes were also studied. As a result, the ZCA membrane displayed significantly improved hydrophilicity and water permeability compared with those of the reference CA membrane, despite a slight decrease in the protein rejection ratio. According to the cycle ultrafiltration performance of bovine serum albumin (BSA) solution and protein adsorption experiment, ZCA membrane exhibited better flux recovery property and fouling resistant ability, especially irreversible fouling resistant ability, suggesting superior antifouling performance. This new approach gives polymer-based membrane a long time life and excellent ultrafiltration performance, and seems promising for potential applications in the protein separation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Observational tests of modified gravity

International Nuclear Information System (INIS)

Jain, Bhuvnesh; Zhang Pengjie

2008-01-01

Modifications of general relativity provide an alternative explanation to dark energy for the observed acceleration of the Universe. Modified gravity theories have richer observational consequences for large-scale structures than conventional dark energy models, in that different observables are not described by a single growth factor even in the linear regime. We examine the relationships between perturbations in the metric potentials, density and velocity fields, and discuss strategies for measuring them using gravitational lensing, galaxy cluster abundances, galaxy clustering/dynamics, and the integrated Sachs-Wolfe effect. We show how a broad class of gravity theories can be tested by combining these probes. A robust way to interpret observations is by constraining two key functions: the ratio of the two metric potentials, and the ratio of the gravitational 'constant' in the Poisson equation to Newton's constant. We also discuss quasilinear effects that carry signatures of gravity, such as through induced three-point correlations. Clustering of dark energy can mimic features of modified gravity theories and thus confuse the search for distinct signatures of such theories. It can produce pressure perturbations and anisotropic stresses, which break the equality between the two metric potentials even in general relativity. With these two extra degrees of freedom, can a clustered dark energy model mimic modified gravity models in all observational tests? We show with specific examples that observational constraints on both the metric potentials and density perturbations can in principle distinguish modifications of gravity from dark energy models. We compare our result with other recent studies that have slightly different assumptions (and apparently contradictory conclusions).

Icodextrin with nitroprusside increases ultrafiltration and peritoneal transport during long CAPD dwells

NARCIS (Netherlands)

Douma, C. E.; Hiralall, J. K.; de Waart, D. R.; Struijk, D. G.; Krediet, R. T.

1998-01-01

Addition of the nitric oxide (NO) donor nitroprusside to 1.36% glucose dialysate enlarges the effective peritoneal surface area during four-hour dwells. The theoretical positive effect on ultrafiltration is, however, counteracted by an increase in glucose absorption. The absorption of the glucose

Treatment of olive mill wastewater by the combination of ultrafiltration and bipolar electrochemical reactor processes

KAUST Repository

Yahiaoui, O.

2011-01-01

The main purpose of this study was to investigate the removal of the chemical oxygen demand (COD) from olive mill wastewater (OMW) by the combination of ultrafiltration with electrocoagulation process. Ultrafiltration process equipped with CERAVER membrane was used as pre-treatment for electrochemical process. The obtained permeate from the ultrafiltration process allowed COD removal efficiency of about 96% from OMW. Obtained permeate with an average COD of about 1.1gdm-3 was treated by electrochemical reactor equipped with a reactor with bipolar iron plate electrodes. The effect of the experimental parameters such as current density, pH, surface electrode/reactor volume ratio and NaCl concentration on COD removal was assessed. The results showed that the optimum COD removal rate was obtained at a current density of 93.3Am-2 and pH ranging from 4.5 to 6.5. At the optimum operational parameters for the experiments, electrocoagulation process could reduce COD from 1.1gdm-3 to 78mgdm-3, allowing direct discharge of the treated OMW as that meets the Algerian wastewater discharge standards (<125mgdm-3). © 2010 Elsevier B.V.

A survey of structure characterization methods for ultrafiltration and reverse osmosis membranes

NARCIS (Netherlands)

Smolders, C.A.; Mulder, M.H.V.; van der Velden, P.M.

1976-01-01

Asymmetric membranes consist of a thin skin, which is permselective to certain molecules in solution, and a porous support, serving as a mechanical support layer and also as a transport layer for the permeate. Both in ultrafiltration and in hyperfiltration (reverse osmosis) asymmetric membranes are

Metal removal from aqueous media by polymer-assisted ultrafiltration with chitosan

Directory of Open Access Journals (Sweden)

Grégorio Crini

2017-05-01

Full Text Available Polymer assisted ultrafiltration (PAUF is a relatively new process in water and wastewater treatment and the subject of an increasing number of papers in the field of membrane science. Among the commercial polymers used, poly(ethyleneimine and poly(acrylic acid are the most popular to complex numerous metal ions. Recently, there is an increasing interest in the use of chitosan, a natural linear polymer, as chelating agent for complexing metals. Chitosan has a high potential in wastewater treatment mainly due to its polyelectrolyte properties at acidic pH. The objectives of this review are to present the PAUF process and to highlight the advantages gained from the use of chitosan in the process of complexation–ultrafiltration. For this, a PAUF-based literature survey has been compiled and is discussed. From these data, chitosan, a biopolymer that is non-toxic to humans and the environment, is found to be effective in removing metal ions and exhibits high selectivity. It might be a promising polyelectrolyte for PAUF purposes.

Crossflow Ultrafiltration for Removing Direct-15 Dye from Wastewater of Textile Industry

Directory of Open Access Journals (Sweden)

A.L. Ahmad

2017-11-01

Full Text Available Ultrafiltration membrane was used to treat the effluent from textile industries. Crossflow ultrafiltration using GN polymeric membrane was used to remove the dye from textile effluent. A synthetic textile effluent of Direct-15 dye was used. The study focused through the effect of feed concentration, transmembrane pressure and solution’s pH on the permeate flux and percentage of dye removal were investigated. Dye concentration had significant effects on flux values. Under the fixed pressures and pH, the flux decreased while the dye rejection increased with increasing feed concentration. Transmembrane pressure also had significant effect on flux values. Under the fixed feed concentration and pH, the flux increased while dye rejection decreased with increasing pressure. Experiment data showed that the highest flux was observed at pH 4 (acidic condition while the highest dye removal observed at pH 7. Data collection could be used to improve the effectiveness of dye removal from textile industry wastewater using membrane technology.

46 CFR 54.10-10 - Standard hydrostatic test (modifies UG-99).

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Standard hydrostatic test (modifies UG-99). 54.10-10... PRESSURE VESSELS Inspection, Reports, and Stamping § 54.10-10 Standard hydrostatic test (modifies UG-99). (a) All pressure vessels shall satisfactorily pass the hydrostatic test prescribed by this section...

Testing for Genetically Modified Foods Using PCR

Science.gov (United States)

Taylor, Ann; Sajan, Samin

2005-01-01

The polymerase chain reaction (PCR) is a Nobel Prize-winning technique that amplifies a specific segment of DNA and is commonly used to test for the presence of genetic modifications. Students use PCR to test corn meal and corn-muffin mixes for the presence of a promoter commonly used in genetically modified foods, the cauliflower mosaic virus 35S…

The processing of used cooking oil (yellow grease) using combination of adsorption and ultrafiltration membrane processes

Science.gov (United States)

Rosnelly, C. M.; Sofyana; Amalia, D.; Sarah, S.

2018-03-01

Yellow grease is used cooking oil whose quality has degraded due to the oxidation, polymerization, or hydrolysis process. In previous studies, yellow grease refining had been conducted either by adsorption or by using membrane. In this study, adsorption process using adsorbent from bagasse activated with H3PO4 12.5%, and ultrafiltration using Polyethersulfone (PES) membrane were combined. In adsorption stage, several variation of bagasse mass was fed into 200 ml of yellow grease and stirred for 60 minutes at 60 rpm. Yellow grease produced from adsorption with best condition was then processed using ultrafiltration membran that is PES membran with concentration by 15 wt % with transmembrane pressure variation by 0.5; 1; 1.5; 2; and 2.5 Bar. Analysis of yellow grease characteristics before refined showed its acid number, peroxide number, iodine number, and water content respectively by 2.68 mgKOH/Kg; 5.97 Meq/Kg; 51,48; and 1.29%. Characteristics of yellow grease after adsorption at its best condition on the parameters of acid number, peroxide number, iodine number, and water content are respectively by 2.55 mgKOH/Kg; 4.19 Meq/Kg; 40,02; and 0.27%. Characteristics of yellow grease after ultrafiltration at its best condition on the parameters of acid number, peroxide number, iodine number, and water content are respectively by 1.12 mgKOH/Kg; 1.8 Meq/Kg; 41,36; and 0.02%. Combination of adsorption and ultrafiltration processes for yellow grease processing showed decreasing value on the parameters of acid number, peroxide number, and water content that conforms to the SNI quality standard, but has not been able to increase the iodine number.

Effects of Using Modified Items to Test Students with Persistent Academic Difficulties

Science.gov (United States)

Elliott, Stephen N.; Kettler, Ryan J.; Beddow, Peter A.; Kurz, Alexander; Compton, Elizabeth; McGrath, Dawn; Bruen, Charles; Hinton, Kent; Palmer, Porter; Rodriguez, Michael C.; Bolt, Daniel; Roach, Andrew T.

2010-01-01

This study investigated the effects of using modified items in achievement tests to enhance accessibility. An experiment determined whether tests composed of modified items would reduce the performance gap between students eligible for an alternate assessment based on modified achievement standards (AA-MAS) and students not eligible, and the…

Ultrafiltration by gyroid nanoporous polymer membranes

DEFF Research Database (Denmark)

Li, Li; Szewczykowski, Piotr Przemyslaw; Clausen, Lydia D.

2011-01-01

the effect of membrane fouling on the flux decline and rejection profiles. Significant fouling occurred in the case of hydrophobic membranes in contact with water solutions, while in the presence of high concentration of ethanol in the filtration solution and in the case of hydrophilized membranes...... the fouling was reduced. The observed rejection of PEG was compared with theoretic predictions, as described by the Bungay–Brenner model. The model satisfactorily described the rejection profile of PEG up to 12kg/mol through hydrophobic membranes in the presence of excess ethanol. A significantly reduced......Gyroid nanoporous cross-linked 1,2-polybutadiene membranes with uniform pores were developed for ultrafiltration applications. The gyroid porosity has the advantage of isotropic percolation with no need for structure pre-alignment. The effects of solvent and surface photo...

Stabilization of flux during dead-end ultra-low pressure ultrafiltration.

Science.gov (United States)

Peter-Varbanets, Maryna; Hammes, Frederik; Vital, Marius; Pronk, Wouter

2010-06-01

Gravity driven ultrafiltration was operated in dead-end mode without any flushing or cleaning. In contrary to general expectations, the flux value stabilized after about one week of operation and remained constant during an extended period of time (several months). Different surface water types and diluted wastewater were used as feed water and, depending on the feed water composition, stable flux values were in the range of 4-10 L h(-1) m(-2). When sodium azide was added to the feed water to diminish the biological activity, no stabilization of flux occurred, indicating that biological processes play an important role in the flux stabilization process. Confocal laser scanning microscopy revealed the presence of a biofouling layer, of which the structure changed over time, leading to relatively heterogeneous structures. It is assumed that the stabilization of flux is related to the development of heterogeneous structures in the fouling layer, due to biological processes in the layer. The phenomenon of flux stabilization opens interesting possibilities for application, for instance in simple and low-cost ultrafiltration systems for decentralized drinking water treatment in developing and transition countries, independent of energy supply, chemicals, or complex process control. 2010 Elsevier Ltd. All rights reserved.

A New Concept of Ultrafiltration Fouling Control : Backwashing with Low Ionic Strength Water

NARCIS (Netherlands)

Li, S.

2011-01-01

Ultrafiltration (UF) is a proven technology in water treatment nowadays. However, fouling remains a major challenge in the operation of UF, especially in regard to colloidal NOM fouling. In general, a number of colloidal NOM fouling mechanisms may occur, such as adsorption, gel formation. Colloidal

Effect of high and low ultrafiltration volume during hemodialysis on relative blood volume

NARCIS (Netherlands)

Dasselaar, JJ; de Jong, PE; Huisman, RM; Franssen, CFM

2006-01-01

Achieving an optimal posthemodialysis hydration status may be difficult because objective criteria for dry weight are lacking. Both relative blood volume changes (Delta RBV) at the end of hemodialysis and Delta RBV normalized for ultrafiltration volume (Delta RBV/UF ratio) have been reported to

Predicting optimal back-shock times in ultrafiltration hollow fibre modules through path-lines

DEFF Research Database (Denmark)

Vinther, Frank; Pinelo, Manuel; Brøns, Morten

2014-01-01

This paper presents a two dimensional mathematical model of back-shocking in ultrafiltration. The model investigates the effect of back-shocking on concentration polarization. The model shows a positive effect on both the volumetric flux and the observed rejection when back-shocking is applied as...

Novel use of an ultrafiltration device as an alternative method for fluid removal in critically ill pediatric patients with cardiac disease: a case series

Directory of Open Access Journals (Sweden)

Sujata Chakravarti

2016-06-01

Full Text Available Fluid overload (FO is a common complication for pediatric patients in the intensive care unit. When conventional therapy fails, hemodialysis or peritoneal dialysis is classically used for fluid removal. Unfortunately, these therapies are often associated with cardiovascular or respiratory instability. Ultrafiltration, using devices such as the AquadexTM system (Baxter Healthcare, Deerfield, IL, USA, is an effective tool for fluid removal in adult patients with congestive heart failure. As compared to hemodialysis, ultrafiltration can be performed using smaller catheters, and the extracorporeal volume and minimal blood flow rates are lower. In addition, there is no associated abdominal distension as is seen in peritoneal dialysis. Consequently, ultrafiltration may be better tolerated in critically ill pediatric patients. We present three cases of challenging pediatric patients with FO in the setting of congenital heart disease in whom ultrafiltration using the AquadexTM system was successfully utilized for fluid removal while cardiorespiratory stability was maintained.

The difference in causes of early and late ultrafiltration failure in peritoneal dialysis

NARCIS (Netherlands)

Smit, Watske; Parikova, Alena; Struijk, Dirk G.; Krediet, Raymond T.

2005-01-01

OBJECTIVE: Ultrafiltration failure (UFF) is a major complication of peritoneal dialysis. Although it seems associated with long-term treatment, it can also occur in recently started patients. To identify the causes of this complication in patients with early and late UFF we studied a group of 48

Removal of chromium (VI) ions from aqueous solutions using amine-impregnated TiO2 nanoparticles modified cellulose acetate membranes.

Science.gov (United States)

Gebru, Kibrom Alebel; Das, Chandan

2018-01-01

In this work, TiO 2 nanoparticles (NPs) were modified using tetraethylenepentamine (TEPA), ethylenediamine (EDA), and hexamethylenetetramine (HMTA) amines using impregnation process. The prepared amine modified TiO 2 samples were explored as an additive to fabricate ultrafiltration membranes with enhanced capacity towards the removal of chromium ions from aqueous solution. Modified membranes were prepared from cellulose acetate (CA) polymer blended with polyethylene glycol (PEG) additive, and amine modified TiO 2 by using phase inversion technique. Fourier transform infrared spectroscopy (FTIR), zeta potential (ζ), thermo gravimetric analysis (TGA), field emission scanning electron microscopy (FESEM), water contact angle (WCA), and atomic absorption spectrophotometer (AAS) studies were done to characterize the membranes in terms of chemical structure, electric charge, thermal stability, morphology, hydrophilicity, and removal performance. The pure water permeability and Cr (VI) ion removal efficiency of the unmodified (i.e. CA/U-Ti) and the amine modified (CA/Ti-HMTA, CA/Ti-EDA, and CA/Ti-TEPA) membranes were dependent on pH and metal ion concentration. Incorporation of amine modified TiO 2 composite to the CA polymer was found to improve the fouling and removal characteristics of the membranes during the chromium ultrafiltration process. The maximum removal efficiency result of Cr (VI) ions at pH of 3.5 using CA/Ti-TEPA membrane was 99.8%. The washing/regeneration cycle results in this study described as an essential part for prospect industrial applications of the prepared membranes. The maximum Cr (VI) removal results by using CA/Ti-TEPA membrane for four washing/regeneration cycles are 99.6%, 99.5%, 98.6% and, 96.6%, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

Stirred cell ultrafiltration of lignin from black liquor generated from South African kraft mills

CSIR Research Space (South Africa)

Kekana, Paul

2016-12-01

Full Text Available Ultrafiltration of lignin from black liquor was carried out in a stirred batch cell using polyethersulfone membranes. Parameters such as operating pressure, feed concentration, stirring rate and membrane cut-off size were varied and their effects...

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

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.

Effects of Wheat Gluten Hydrolysate and Its Ultrafiltration Fractions on Dough Properties and Bread Quality

Directory of Open Access Journals (Sweden)

Mouming Zhao

2007-01-01

Full Text Available Two fractions (50-K and permeate from a proteolytic hydrolysate (degree of hydrolysis, DH=3.8 % of wheat gluten were separated using ultrafiltration (UF membrane with molecular mass cut-off of 50 kDa. The effects of the wheat gluten hydrolysate (WGH and its UF fractions on the mixing behaviour and viscoelastic properties of wheat dough were presented. The WGH and its UF fractions modified the mixing properties of dough. The addition of these fractions improved the viscoelastic characteristics of wheat dough. A significant (p<0.05 effect of 50-K fraction on these characteristics of wheat dough was observed. After adding these fractions, the bread was considered acceptable by the sensory panel. Also, 50-K fraction resulted in significant (p<0.05 increase in the crumb firmness, while the bread made with wheat flour with WGH and permeate (P fraction showed softer crumbs compared to that of wheat flour. Moreover, these fractions had anti-staling properties for bread during storage. Hence, the wheat gluten hydrolysate and its UF fractions are the products with promising potential in the baking products.

Studies for the use of water soluble chelating polymer in ultra-filtration technique for the removal of uranium from aqueous solutions

International Nuclear Information System (INIS)

Misra, S.K.; Mahatele, A.K.; Tripathi, S.C.; Vijayan, K.; Munshi, S.K.

2005-01-01

Studies were carried out for the removal of uranium from aqueous medium using water soluble chelating polymer by ultra-filtration technique. The water soluble polymers are the option for the surfactants used in the micellar enhanced ultra-filtration technique. More than 95% separation of uranium carried out under different experimental conditions, suggest that the technique can be effectively employed for the removal uranium from the aqueous effluent streams. (author)

The effect of protein-protein and protein-membrane interactions on membrane fouling in ultrafiltration

NARCIS (Netherlands)

Huisman, I.H.; Prádanos, P.; Hernández, A.

2000-01-01

It was studied how protein-protein and protein-membrane interactions influence the filtration performance during the ultrafiltration of protein solutions over polymeric membranes. This was done by measuring flux, streaming potential, and protein transmission during filtration of bovine serum albumin

Slow ultrafiltration for continuous in vivo sampling : application for glucose and lactate in man

NARCIS (Netherlands)

Tiessen, RG; Kaptein, WA; Venema, K; Korf, J

1999-01-01

Background: An ultrafiltration (UF) technique was developed for continuous subcutaneous (s.c.) sampling and on-line analysis of absolute glucose and lactate concentrations in tissue. The relation between subcutaneous and blood concentrations was studied in men, because a subcutaneous monitoring

Ultrafiltration of protein solutions; the role of protein association in rejection and osmotic pressure

NARCIS (Netherlands)

van den Berg, G.B.; Hanemaaijer, J.H.; Smolders, C.A.

1987-01-01

The monomer-dimer equilibrium of the protein β-lactoglobulin under neutral conditions appears to influence the rejection and the osmotic pressure build-up, both phenomena closely related to ultrafiltration. Rejection measurements indicate different rejections for the β-lactoglobulin monomers and

Optimisation of ultrafiltration of a highly viscous protein solution using spiral-wound modules

DEFF Research Database (Denmark)

Lipnizki, Jens; Casani, S.; Jonsson, Gunnar Eigil

2005-01-01

The ultrafiltration process of highly viscous protein process water with spiral-wound modules was optimised by analysing the fouling and developing a strategy to reduce it. It was shown that the flux reduction during filtration is mainly caused by the adsorption of proteins on the membrane and no...

Evaluation of Removal Mechanisms in a Graphene Oxide-Coated Ceramic Ultrafiltration Membrane for Retention of Natural Organic Matter, Pharmaceuticals, and Inorganic Salts.

Science.gov (United States)

Chu, Kyoung Hoon; Fathizadeh, Mahdi; Yu, Miao; Flora, Joseph R V; Jang, Am; Jang, Min; Park, Chang Min; Yoo, Sung Soo; Her, Namguk; Yoon, Yeomin

2017-11-22

Functionalized graphene oxide (GO), derived from pure graphite via the modified Hummer method, was used to modify commercially available ceramic ultrafiltration membranes using the vacuum method. The modified ceramic membrane functionalized with GO (ceramic GO ) was characterized using a variety of analysis techniques and exhibited higher hydrophilicity and increased negative charge compared with the pristine ceramic membrane. Although the pure water permeability of the ceramic GO membrane (14.4-58.6 L/m 2 h/bar) was slightly lower than that of the pristine membrane (25.1-62.7 L/m 2 h/bar), the removal efficiencies associated with hydrophobic attraction and charge effects were improved significantly after GO coating. Additionally, solute transport in the GO nanosheets of the ceramic GO membrane played a vital role in the retention of target compounds: natural organic matter (NOM; humic acid and tannic acid), pharmaceuticals (ibuprofen and sulfamethoxazole), and inorganic salts (NaCl, Na 2 SO 4 , CaCl 2 , and CaSO 4 ). While the retention efficiencies of NOM, pharmaceuticals, and inorganic salts in the pristine membrane were 74.6%, 15.3%, and 2.9%, respectively, these increased to 93.5%, 51.0%, and 31.4% for the ceramic GO membrane. Consequently, the improved removal mechanisms of the membrane modified with functionalized GO nanosheets can provide efficient retention for water treatment under suboptimal environmental conditions of pH and ionic strength.

Effect of transmembrane pressure control on energy efficiency during skim milk concentration by ultrafiltration at 10 and 50°C.

Science.gov (United States)

Méthot-Hains, S; Benoit, S; Bouchard, C; Doyen, A; Bazinet, L; Pouliot, Y

2016-11-01

The efficiency of the ultrafiltration process during skim milk concentration was studied using both dynamic and constant (465 or 672kPa) transmembrane pressure experiments at refrigerated temperature (10°C) and high temperature (50°C). The pilot-scale module was equipped with a 10-kDa polyethersulfone spiral-wound membrane element with a surface area of 2.04m 2 . Permeation flux, resistance-in-series model, mineral and protein rejection, and energy consumption were studied as a function of temperature and transmembrane pressure applied. Higher permeation flux values were systematically obtained at 50°C. Also, a significant temperature effect was found for calcium rejection, which was lower at 10°C compared with 50°C. Total hydraulic resistance and reversible fouling resistance were higher at 50°C than at 10°C. No change in protein rejection was observed, depending on the operating mode studied. Permeation flux, which was higher at 50°C, had lower pumping energy consumption compared with ultrafiltration at the colder temperature. Also, the low ultrafiltration temperature required a higher total energy consumption to reach the 3.6× retentate compared with ultrafiltration at 50°C. Overall, our study shows that the operating parameters and temperature can be optimized using an energy efficiency ratio. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Recovery of biomolecules from marinated herring (Clupea harengus) brine using ultrafiltration through ceramic membranes

DEFF Research Database (Denmark)

Gringer, Nina; Hosseini, Seyed Vali; Svendsen, Tore

2015-01-01

Marinated herring processing brines, which are usually discarded, are rich in salt, protein, non-protein nitrogen, iron, fatty acids, antioxidant and even possess enzymatic activity. This study investigated the performance of ceramic ultrafiltration of two herring spice brines with a major focus...

A feasibility study of ultrafiltration/reverse osmosis (UF/RO)-based wastewater treatment and reuse in the metal finishing industry

DEFF Research Database (Denmark)

Petrinic, Irena; Korenak, Jasmina; Povodnik, Damijan

2015-01-01

that the ultrafiltration-reverse osmosis treatment removed between 91.3% and 99.8% of the contaminants from the effluent, such as metal elements, organic, and inorganic compounds. Contaminants such as suspended solids, nickel, ammonium nitrogen, sulphate nitrogen, chemical oxygen demand, and biochemical oxygen demand were...... completely removed, the concentrations in the permeate being under the detection limits, thus the quality of the ultrafiltration-reverse osmosis process met the reuse criteria. This demonstrates the technological feasibility of wastewater reuse during electro-plating processes and the pre-treatment of powder...

Pretreatment Engineering Platform Phase 1 Final Test Report

Energy Technology Data Exchange (ETDEWEB)

Kurath, Dean E.; Hanson, Brady D.; Minette, Michael J.; Baldwin, David L.; Rapko, Brian M.; Mahoney, Lenna A.; Schonewill, Philip P.; Daniel, Richard C.; Eslinger, Paul W.; Huckaby, James L.; Billing, Justin M.; Sundar, Parameshwaran S.; Josephson, Gary B.; Toth, James J.; Yokuda, Satoru T.; Baer, Ellen BK; Barnes, Steven M.; Golovich, Elizabeth C.; Rassat, Scot D.; Brown, Christopher F.; Geeting, John GH; Sevigny, Gary J.; Casella, Amanda J.; Bontha, Jagannadha R.; Aaberg, Rosanne L.; Aker, Pamela M.; Guzman-Leong, Consuelo E.; Kimura, Marcia L.; Sundaram, S. K.; Pires, Richard P.; Wells, Beric E.; Bredt, Ofelia P.

2009-12-23

Pacific Northwest National Laboratory (PNNL) was tasked by Bechtel National Inc. (BNI) on the River Protection Project, Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to conduct testing to demonstrate the performance of the WTP Pretreatment Facility (PTF) leaching and ultrafiltration processes at an engineering-scale. In addition to the demonstration, the testing was to address specific technical issues identified in Issue Response Plan for Implementation of External Flowsheet Review Team (EFRT) Recommendations - M12, Undemonstrated Leaching Processes.( ) Testing was conducted in a 1/4.5-scale mock-up of the PTF ultrafiltration system, the Pretreatment Engineering Platform (PEP). Parallel laboratory testing was conducted in various PNNL laboratories to allow direct comparison of process performance at an engineering-scale and a laboratory-scale. This report presents and discusses the results of those tests.

Pretreatment Engineering Platform Phase 1 Final Test Report

International Nuclear Information System (INIS)

Kurath, Dean E.; Hanson, Brady D.; Minette, Michael J.; Baldwin, David L.; Rapko, Brian M.; Mahoney, Lenna A.; Schonewill, Philip P.; Daniel, Richard C.; Eslinger, Paul W.; Huckaby, James L.; Billing, Justin M.; Sundar, Parameshwaran S.; Josephson, Gary B.; Toth, James J.; Yokuda, Satoru T.; Baer, Ellen B.K.; Barnes, Steven M.; Golovich, Elizabeth C.; Rassat, Scot D.; Brown, Christopher F.; Geeting, John G.H.; Sevigny, Gary J.; Casella, Amanda J.; Bontha, Jagannadha R.; Aaberg, Rosanne L.; Aker, Pamela M.; Guzman-Leong, Consuelo E.; Kimura, Marcia L.; Sundaram, S.K.; Pires, Richard P.; Wells, Beric E.; Bredt, Ofelia P.

2009-01-01

Pacific Northwest National Laboratory (PNNL) was tasked by Bechtel National Inc. (BNI) on the River Protection Project, Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to conduct testing to demonstrate the performance of the WTP Pretreatment Facility (PTF) leaching and ultrafiltration processes at an engineering-scale. In addition to the demonstration, the testing was to address specific technical issues identified in Issue Response Plan for Implementation of External Flowsheet Review Team (EFRT) Recommendations - M12, Undemonstrated Leaching Processes. Testing was conducted in a 1/4.5-scale mock-up of the PTF ultrafiltration system, the Pretreatment Engineering Platform (PEP). Parallel laboratory testing was conducted in various PNNL laboratories to allow direct comparison of process performance at an engineering-scale and a laboratory-scale. This report presents and discusses the results of those tests.

THE MUNICIPAL SEWAGE TREATMENT PLANT EFFLUENT POLISHING IN ULTRAFILTRATION

Directory of Open Access Journals (Sweden)

Mariusz Dudziak

2017-08-01

Full Text Available The effluent from the municipal sewage treatment plant was comparatively treated in the ultrafiltration process using ceramic and polymer membranes. Filtration was carried out in the cross-flow system under the conditions of the transmembrane process pressure 0.1 MPa - the ceramic membrane and 0.2 MPa – the polymer membrane at a temperature of 20°C. The effectiveness of the process had been assessed by various physical and chemical analyses (pH, turbidity, color, absorbance, TOC and phenol index. There was included the toxicological assessment (by applying as an indicator organism the bioluminescence bacteria Aliivibrio fischeri and microbiological assessment of tested samples. During filtration there was studied the hydraulic efficiency of membranes. Is was specified, that the efficiency of the process depends on the conditions of membrane filtration, wherein the better effects of the removal of organic pollutants had been noted in the case of polymer membrane than ceramic membrane. However, the polymer membrane, in the comparison to the ceramic membrane, was more susceptible to pore blocking, which caused the reduction of hydraulic efficiency. Regardless of what type of membrane the permeats were not toxic and did not contain microorganisms.

Removal of cellular-type hemoglobin-based oxygen carrier (hemoglobin-vesicles) from blood using centrifugation and ultrafiltration.

Science.gov (United States)

Sakai, Hiromi; Sou, Keitaro; Horinouchi, Hirohisa; Tsuchida, Eishun; Kobayashi, Koichi

2012-02-01

The hemoglobin-vesicle (HbV) is an artificial oxygen carrier encapsulating a concentrated hemoglobin solution in a phospholipid vesicle (liposome). During or after transporting oxygen, macrophages capture HbVs in the reticuloendothelial system (RES) with an approximate circulation half-life of 3 days. Animal studies show transient splenohepatomegaly after large doses, but HbVs were completely degraded, and the components were excreted in a few weeks. If a blood substitute is used for emergency use until red blood cell transfusion becomes available or for temporary use such as a priming fluid for an extracorporeal circuit, then one option would be to remove HbVs from the circulating blood without waiting a few weeks for removal by the RES. Using a mixture of beagle dog whole blood and HbV, we tested the separation of HbV using a centrifugal Fresenius cell separator and an ultrafiltration system. The cell separator system separated the layers of blood cell components from the HbV-containing plasma layer by centrifugal force, and then the HbV was removed from plasma phase by the ultrafiltration system. The HbVs (250-280 nm) are larger than plasma proteins (blood cell components (> 3 µm). The size of HbVs is advantageous to be separated from the original blood components, and the separated blood components can be returned to circulation. © 2011, Copyright the Authors. Artificial Organs © 2011, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Evaluation of coagulation factors and platelet function from an off-line modified ultrafiltration technique for post-cardiopulmonary bypass circuit blood recovery.

Science.gov (United States)

Beckmann, S; Lynn, P; Miller, S; Harris, R; DiMarco, R F; Ross, J E

2013-05-01

Modified ultrafiltration (MUF) is a technique that hemoconcentrates residual CPB circuit blood and the patient at the same time. Hemoconcentration and MUF are Class 1-A recommendations in the anesthesia and surgical blood conservation guidelines. This study evaluated the off-line MUF process of the Hemobag (HB, Global Blood Resources, Somers, CT, USA) to quantitate coagulation factor levels, platelet (PLT) count and function in one facility and cellular growth factor concentrations of the final product that were transfused to the patient in another facility In two cardiac surgery facilities, after decannulation, the extracorporeal circuit (ECC) blood from 22 patients undergoing cardiac surgery was processed with the HB device. In eleven patients from the first facility by the study design, blood samples for coagulation factor levels and PLT aggregation were drawn from the reservoir of the MUF device pre- and post-processing. The samples (n = 11) were sent to a reference laboratory where testing for prothrombin time (PT), international normalized ratio (INR), activated partial thromboplastin time (aPTT), reptilase time, fibrinogen, clotting factors II, V, VII, VIII, IX, X, ADAMTS-13, protein C, protein S, antithrombin III, von Willebrand Factor (vWF), and platelet (PLT) aggregation were performed. A portion of the final concentrated HB blood samples (n = 5-10) from the second facility by design were evaluated for transforming and platelet-derived cellular growth factor concentrations. On average, approximately 800 - 2000 mls of whole blood were removed from the ECC post-CPB for processing in the HB device. After processing, there was, on the average, approximately 300 - 950 mls of concentrated whole blood salvaged for reinfusion. The PT and INR were significantly lower in the post-processing product compared to the pre-processing samples while the aPTT times were not significantly different. All coagulation factors and natural anti-coagulants were significantly

Focused ultrasound-modulated glomerular ultrafiltration assessed by functional changes in renal arteries.

Directory of Open Access Journals (Sweden)

Feng-Yi Yang

Full Text Available This study demonstrates the feasibility of using focused ultrasound (FUS to modulate glomerular ultrafiltration by renal artery sonication and determine if protein-creatinine ratios are estimated through vascular parameters. All animal experiments were approved by our Animal Care and Use Committee. The renal arteries of Sprague-Dawley rats were surgically exposed and sonicated at various acoustic power levels using a FUS transducer with a resonant frequency of 1 MHz. The mean peak systolic velocity (PSV of the blood flow was measured by Doppler ultrasound imaging. Urinary protein-creatinine ratios were calculated during the experiments. Histological examination of renal arteries and whole kidneys was performed. The PSV, pulsatility index, and resistance index of blood flow significantly increased in the arteries after FUS sonication without microbubbles (p<0.05. The change in normalized protein-creatinine ratios significantly increased with increasing acoustic power, but such was not observed when microbubbles were administered. Furthermore, no histological changes were observed in the hematoxylin- and eosin-stained sections. Glomerular ultrafiltration is regulated temporarily by renal artery sonication without microbubbles. Monitoring vascular parameters are useful in estimating the normalized change in protein-creatinine ratios.

Enhancing performance and surface antifouling properties of polysulfone ultrafiltration membranes with salicylate-alumoxane nanoparticles

Science.gov (United States)

Mokhtari, Samaneh; Rahimpour, Ahmad; Shamsabadi, Ahmad Arabi; Habibzadeh, Setareh; Soroush, Masoud

2017-01-01

To improve the hydrophilicity and antifouling properties of polysulfone (PS) ultrafiltration membranes, we studied the use of salicylate-alumoxane (SA) nanoparticles as a novel hydrophilic additive. The effects of SA nanoparticles on the membrane characteristics and performance were investigated in terms of membrane structure, permeation flux, solute rejection, hydrophilicity, and antifouling ability. The new mixed-matrix membranes (MMMs) possess asymmetric structures. They have smaller finger-like pores and smoother surfaces than the neat PS membranes. The embedment of SA nanoparticles in the polymer matrix and the improvement of surface hydrophilicity were investigated. Ultrafiltration experiments indicated that the pure-water flux of the new MMMs initially increases with SA nanoparticles loading followed by a decrease at high loadings. Higher BSA solution flux was achieved for the MMMs compared to the neat PS membranes. Membranes with 1 wt.% SA nanoparticles exhibit the highest flux recovery ratio of 87% and the lowest irreversible fouling of 13%.

Application of Combined Cake Filtration-Complete Blocking Model to Ultrafiltration of Skim Milk

Directory of Open Access Journals (Sweden)

Mansoor Kazemimoghadam

2017-10-01

Full Text Available Membrane ultrafiltration (UF is widely used in dairy industries like milk concentration and dehydration processes. The limiting factor of UF systems is fouling which is defined as the precipitation of solutes in the form of a cake layer on the surface of the membrane. In this study, the combined cake filtration-complete blocking model was compared to cake filtration mechanism for flux data through ultrafiltration of skim milk at constant flow rate. The resistance data also was modeled using cake filtration model and standard blocking model. The effect of different trans-membrane pressures and temperatures on flux decline was then investigated. Based on the results obtained here, the combined complete blocking-cake formation model was in excellent agreement with experimental data. The cake filtration model also provided good data fits and can be applied to solutions whose solutes tend to accumulate on the surface of the membrane in the form of a cake layer. With increasing pressure, the differences between the model and experimental data increased.

Whey pretreatments before ultrafiltration

Directory of Open Access Journals (Sweden)

Tuomo Tupasela

1994-09-01

Full Text Available Whey is a by-product of cheesemaking. Whey dry matter contains mainly lactose, but also valuable whey proteins. The aim of this study was to develop improvements to whey protein membrane isolation processes. In our trials CaCl2 -added, pH-adjusted and heat-treated wheys were found to have MF (microfiltration permeate fluxes about 30% higher than in untreated MF whey. The total solids and protein content of the MF permeates decreased compared to the original wheys. UF (ultrafiltration trials were conducted using MF whey to compare it with centrifugally separated whey. The MF whey consistently maintained an UF flux about 1.5 to 2.5 times higher than that of the separated whey. Differently treated MF whey UF permeate fluxes also showed a difference. With CaCl2 addition, pH adjustment and heat treatment, the UF permeate fluxes were about 20 to 40% higher than when only MF was used. The total solids content decreased in each trial. The protein content of the UF concentrate also decreased compared to the MF permeate. The (β-lg (β-lactoglobulin and α-la (α-lactalbumin content was almost the same in UF concentrates as in MF permeates.

Influence of Surface Properties of Filtration-Layer Metal Oxide on Ceramic Membrane Fouling during Ultrafiltration of Oil/Water Emulsion.

Science.gov (United States)

Lu, Dongwei; Zhang, Tao; Gutierrez, Leo; Ma, Jun; Croué, Jean-Philippe

2016-05-03

In this work, ceramic ultrafiltration membranes deposited with different metal oxides (i.e., TiO2, Fe2O3, MnO2, CuO, and CeO2) of around 10 nm in thickness and similar roughness were tested for O/W emulsion treatment. A distinct membrane fouling tendency was observed, which closely correlated to the properties of the filtration-layer metal oxides (i.e., surface hydroxyl groups, hydrophilicity, surface charge, and adhesion energy for oil droplets). Consistent with the distinct bond strength of the surface hydroxyl groups, hydrophilicity of these common metal oxides is quite different. The differences in hydrophilicity consequently lead to different adhesion of these metal oxides toward oil droplets, consistent with the irreversible membrane fouling tendency. In addition, the surface charge of the metal oxide opposite to that of emulsion can help to alleviate irreversible membrane fouling in ultrafiltration. Highly hydrophilic Fe2O3 with the lowest fouling tendency could be a potential filtration-layer material for the fabrication/modification of ceramic membranes for O/W emulsion treatment. To the best of our knowledge, this is the first study clearly showing the correlations between surface properties of filtration-layer metal oxides and ceramic membrane fouling tendency by O/W emulsion.

Influence of surface properties of filtration-layer metal oxide on ceramic membrane fouling during ultrafiltration of oil/water emulsion

KAUST Repository

Lu, Dongwei; Zhang, Tao; Gutierrez, Leo; Ma, Jun; Croue, Jean-Philippe

2016-01-01

In this work, ceramic ultrafiltration membranes deposited with different metal oxides (i.e., TiO2, Fe2O3, MnO2, CuO, and CeO2) of around 10 nm in thickness and similar roughness were tested for O/W emulsion treatment. Distinct membrane fouling tendency was observed, which closely correlated to the properties of the filtration-layer metal oxides (i.e. surface hydroxyl groups, hydrophilicity, surface charge, and adhesion energy for oil droplets). In consistent with the distinct bond strength of the surface hydroxyl groups, hydrophilicity of these common metal oxides are quite different. The differences in hydrophilicity consequently lead to different adhesion of these metal oxides towards oil droplets which consists very well with irreversible membrane fouling tendency. In addition, the surface charge of the metal oxide opposite to that of emulsion can help to alleviate irreversible membrane fouling in ultrafiltration. Highly hydrophilic Fe2O3 with lowest fouling tendency could be a potential filtration-layer material for the fabrication/modification of ceramic membranes for O/W emulsion treatment. To the best of our knowledge, this is the first study clearly showing the correlations between surface properties of filtration-layer metal oxides and ceramic membrane fouling tendency by O/W emulsion.

Influence of surface properties of filtration-layer metal oxide on ceramic membrane fouling during ultrafiltration of oil/water emulsion

KAUST Repository

Lu, Dongwei

2016-04-01

In this work, ceramic ultrafiltration membranes deposited with different metal oxides (i.e., TiO2, Fe2O3, MnO2, CuO, and CeO2) of around 10 nm in thickness and similar roughness were tested for O/W emulsion treatment. Distinct membrane fouling tendency was observed, which closely correlated to the properties of the filtration-layer metal oxides (i.e. surface hydroxyl groups, hydrophilicity, surface charge, and adhesion energy for oil droplets). In consistent with the distinct bond strength of the surface hydroxyl groups, hydrophilicity of these common metal oxides are quite different. The differences in hydrophilicity consequently lead to different adhesion of these metal oxides towards oil droplets which consists very well with irreversible membrane fouling tendency. In addition, the surface charge of the metal oxide opposite to that of emulsion can help to alleviate irreversible membrane fouling in ultrafiltration. Highly hydrophilic Fe2O3 with lowest fouling tendency could be a potential filtration-layer material for the fabrication/modification of ceramic membranes for O/W emulsion treatment. To the best of our knowledge, this is the first study clearly showing the correlations between surface properties of filtration-layer metal oxides and ceramic membrane fouling tendency by O/W emulsion.

Analysis of ultrafiltration failure in peritoneal dialysis patients by means of standard peritoneal permeability analysis

NARCIS (Netherlands)

Ho-Dac-Pannekeet, M. M.; Atasever, B.; Struijk, D. G.; Krediet, R. T.

1997-01-01

BACKGROUND: Ultrafiltration failure (UFF) is a complication of peritoneal dialysis (PD) treatment that occurs especially in long-term patients. Etiological factors include a large effective peritoneal surface area [measured as high mass transfer area coefficient (MTAC) of creatinine], a high

Operating considerations of ultrafiltration in enzyme enhanced carbon capture

DEFF Research Database (Denmark)

Deslauriers, Maria Gundersen; Gladis, Arne; Fosbøl, Philip Loldrup

2017-01-01

capture capacity of 1 MTonn CO2/year, and is here operated for one year continuously. This publication compares soluble enzymes dissolved in a capture solvent with and without the use of ultrafiltration membranes. The membranes used here have an enzyme retention of 90%, 99% and 99.9%. Enzyme retention......Today, enzyme enhanced carbon capture and storage (CCS) is gaining interest, since it can enable the use of energy efficient solvents, and thus potentially reduce the carbon footprint of CCS. However, a limitation of this technology is the high temperatures encountered in the stripper column, which...

Ultrafiltration technique in conjunction with competing ligand exchange method for Ni–humics speciation in aquatic environment

Digital Repository Service at National Institute of Oceanography (India)

Chakraborty, P.; Boissel, M.; Reuillon, A.; Babu, P.V.R.; Parthiban, G.

The combination of ultrafiltration technique with competing ligand exchange method provides a better understanding of interactions between Ni and different molecular weight fractions of humic acid (HA) at varying pH in aquatic environment...

Effect of skim milk treated with high hydrostatic pressure on permeate flux and fouling during ultrafiltration.

Science.gov (United States)

Leu, Mathilde; Marciniak, Alice; Chamberland, Julien; Pouliot, Yves; Bazinet, Laurent; Doyen, Alain

2017-09-01

Ultrafiltration (UF) is largely used in the dairy industry to generate milk and whey protein concentrate for standardization of milk or production of dairy ingredients. Recently, it was demonstrated that high hydrostatic pressure (HHP) extended the shelf life of milk and improved rennet coagulation and cheese yield. Pressurization also modified casein micelle size distribution and promoted aggregation of whey proteins. These changes are likely to affect UF performance. Consequently, this study determined the effect of skim milk pressurization (300 and 600 MPa, 5 min) on UF performance in terms of permeate flux decline and fouling. The effect of HHP on milk proteins was first studied and UF was performed in total recycle mode at different transmembrane pressures to determine optimal UF operational parameters and to evaluate the effect of pressurization on critical and limiting fluxes. Ultrafiltration was also performed in concentration mode at a transmembrane pressure of 345 kPa for 130 or 140 min to evaluate the decline of permeate flux and to determine fouling resistances. It was observed that average casein micelle size decreased by 32 and 38%, whereas β-lactoglobulin denaturation reached 30 and 70% at 300 and 600 MPa, respectively. These results were directly related to UF performance because initial permeate fluxes in total recycle mode decreased by 25% at 300 and 600 MPa compared with nonpressurized milk, critical flux, and limiting flux, which were lower during UF of milk treated with HHP. During UF in concentration mode, initial permeate fluxes were 30% lower at 300 and 600 MPa compared with the control, but the total flux decline was higher for nonpressurized milk (62%) compared with pressure-treated milk (30%). Fouling resistances were similar, whatever the treatment, except at 600 MPa where irreversible fouling was higher. Characterization of the fouling layer showed that caseins and β-lactoglobulin were mainly involved in membrane fouling after UF of

Performances on Symbol Digit Modalities Test, Color Trails Test, and modified Stroop test in a healthy, elderly Danish sample

DEFF Research Database (Denmark)

Vogel, Asmus; Stokholm, Jette; Jørgensen, Kasper

2013-01-01

This study presents Danish data for the Symbol Digit Modalities Test (SDMT), Color Trails Test (CTT), and a modified Stroop test from 100 subjects aged 60-87 years. Among the included demographic variables, age had the highest impact on test performances. Thus, the study presents separate data...

Modified Valsalva test differentiates primary from secondary cough headache.

Science.gov (United States)

Lane, Russell J M; Davies, Paul T G

2013-03-28

The current definition of cough headache includes provocation of the symptom by Valsalva manoeuvre, and it is generally believed that all cough headache results from a sudden increase in intracranial pressure. We sought to question that presumption and to determine whether the Valsalva test might distinguish primary from secondary cough headache. We examined 16 consecutive cough headache patients using a modified Valsalva test (exhalation into the connecting tube of a standard anaeroid sphygmomanometer to 60 mm Hg for 10 seconds). A positive response was recorded if the manoeuvre provoked headache. All patients subsequently underwent brain MRI. None of the patients had neurological signs. Eleven had positive modified Valsalva tests. Ten were found subsequently to have posterior fossa pathologies (secondary cough headache: 8 Chiari Type 1 malformations, 2 posterior fossa meningiomas). The cough headache was relieved following surgery in all cases. One patient with a positive Valsalva test had an apparently normal brain MRI but measurements of hindbrain and posterior fossa dimensions were consistent with 'posterior fossa crowdedness'. The remaining 5 patients had negative (4 patients) or equivocal (1 patient) Valsalva tests and normal MRI scans (primary cough headache). These findings suggest that secondary cough headache results from a transient increase in intracranial CSF pressure during exertion in the presence of obstruction to normal cerebrospinal fluid dynamics. The modified Valsalva test can also determine whether tonsillar herniation found on brain MRI is symptomatic. Primary cough headache appears to be caused by a different mechanism, possibly through congestion of the orbital venous plexus in the presence of jugular venous incompetence and a reduced threshold for trigeminal sensory activation.

The evaluation of hollow-fiber ultrafiltration and celite concentration of enteroviruses, adenoviruses and bacteriophage from different water matrices

Data.gov (United States)

U.S. Environmental Protection Agency — The data to support the evaluation of hollow-fiber ultrafiltration and celite concentration of enteroviruses, adenoviruses and bacteriophage from different water...

The development of a modified spectral ripple test.

Science.gov (United States)

Aronoff, Justin M; Landsberger, David M

2013-08-01

Poor spectral resolution can be a limiting factor for hearing impaired listeners, particularly for complex listening tasks such as speech understanding in noise. Spectral ripple tests are commonly used to measure spectral resolution, but these tests contain a number of potential confounds that can make interpretation of the results difficult. To measure spectral resolution while avoiding those confounds, a modified spectral ripple test with dynamically changing ripples was created, referred to as the spectral-temporally modulated ripple test (SMRT). This paper describes the SMRT and provides evidence that it is sensitive to changes in spectral resolution.

Preparation of Cu{sub 2}O nanowire-blended polysulfone ultrafiltration membrane with improved stability and antimicrobial activity

Energy Technology Data Exchange (ETDEWEB)

Xu, Zehai; Ye, Shuaiju; Fan, Zheng; Ren, Fanghua; Gao, Congjie [Zhejiang University of Technology, Institute of Oceanic and Environmental Chemical Engineering, College of Chemical Engineering and Material Science and College of Ocean, and State Key Lab Breeding Base of Green Chemical Synthesis Technology and Zhejiang Collaborative Innovation Center of Membrane Separation and Water Treatment (China); Li, Qingbiao; Li, Guoqing [Quanzhou Normal University, College of Chemistry and Life Science (China); Zhang, Guoliang, E-mail: membrane86571@163.com, E-mail: guoliangz@zjut.edu.cn [Zhejiang University of Technology, Institute of Oceanic and Environmental Chemical Engineering, College of Chemical Engineering and Material Science and College of Ocean, and State Key Lab Breeding Base of Green Chemical Synthesis Technology and Zhejiang Collaborative Innovation Center of Membrane Separation and Water Treatment (China)

2015-10-15

Polysulfone (PSF) membranes have been widely applied in water and wastewater treatment, food-processing and biomedical fields. In this study, we report the preparation of modified PSF membranes by blending PSF with Cu{sub 2}O nanowires (NWs) to improve their stability and antifouling activity. Synthesis of novel Cu{sub 2}O NWs/PSF-blended ultrafiltration membrane was achieved via phase inversion method by dispersing one-dimensional Cu{sub 2}O nanowires in PSF casting solutions. Various techniques such as XRD, SEM, TEM, and EDS were applied to characterize and investigate the properties of nanowires and membranes. The introduced Cu{sub 2}O nanowires can firmly be restricted into micropores of PSF membranes, and therefore, they can effectively prevent the serious leaking problem of inorganic substances in separation process. The blended PSF membranes also provided enhanced antimicrobial activity and superior permeation property compared to pure PSF membrane. The overall work can not only provide a new way for preparation of novel blended membranes with multidimensional nanomaterials, but can also be beneficial to solve the annoying problem of biofouling.

Modeling of Hollow-Fiber Membrane System During Ultrafiltration

International Nuclear Information System (INIS)

EI-Bialy, S.H.

2004-01-01

The present study aims to evaluate the performance of hollow fiber membrane module during ultrafiltration of aqueous solutions. The model is represented by a set of differential equations for permeate and residue pressure drop and volumetric flow rates in the axial direction, beside the principle equations of both solvent and solute fluxes through the membrane, while osmotic pressure was neglected in model equations. The shell and tube module type was considered where feed pass in the shell and permeate in the bore side. Tortousily factor of membrane pores in addition to concentration polarization modulus were taken into account in calculations. The model was solved numerically with the help of suitable program in both co current and countercurrent flow pattern and comparison of results were carried out

Maximizing Production Capacity from an Ultrafiltration Process at the Hanford Department of Waste Treatment Facility

International Nuclear Information System (INIS)

Foust, Henry C.; Holton, Langdon K.; Demick, Laurence E.

2005-01-01

The Department of Energy has contracted Bechtel National, Inc. to design, construct and commission a Waste Treatment and Immobilization Plant (WTP) to treat radioactive slurry currently stored in underground waste storage tanks. A critical element of the waste treatment capacity for the WTP is the proper operation of an ultrafiltration process (UFP). The UFP separates supernate solution from radioactive solids. The solution and solid phases are separately immobilized. An oversight review of the UFP design and operation has identified several methods to improve the capacity of the ultrafiltration process, which will also improve the capacity of the WTP. Areas explored were the basis of design, an analysis of the WTP capacity, process chemistry within the UFP, and UFP process control. This article discusses some of the findings of this oversight review in terms of sodium and solid production, which supports the treatment of low activity waste (LAW) associated with the facility, and solid production, which supports the treatment of high level waste (HLW) associated with the facility

The use of ultrafiltration for the clean-up of alkaline Pu containing effluents

International Nuclear Information System (INIS)

Biddle, P.; Gutman, R.G.

1983-07-01

Ultrafiltration has been used to clean up low level Pu solutions at high pH. The decontamination factors achieved were greater than 1000 and were significantly higher than those attained by sedimentation or centrifugation. The results confirmed the findings of earlier work based on the use of Th as a simulant for Pu. A preliminary flowsheet for the decontamination of Pu oxalate liquors is proposed. (author)

Novel test of modified Newtonian dynamics with gas rich galaxies.

Science.gov (United States)

McGaugh, Stacy S

2011-03-25

The current cosmological paradigm, the cold dark matter model with a cosmological constant, requires that the mass-energy of the Universe be dominated by invisible components: dark matter and dark energy. An alternative to these dark components is that the law of gravity be modified on the relevant scales. A test of these ideas is provided by the baryonic Tully-Fisher relation (BTFR), an empirical relation between the observed mass of a galaxy and its rotation velocity. Here, I report a test using gas rich galaxies for which both axes of the BTFR can be measured independently of the theories being tested and without the systematic uncertainty in stellar mass that affects the same test with star dominated spirals. The data fall precisely where predicted a priori by the modified Newtonian dynamics. The scatter in the BTFR is attributable entirely to observational uncertainty, consistent with a single effective force law.

Chemical composition and properties of spray-dried sugar beet concentrate obtained after ultrafiltration of diffusion juice

Directory of Open Access Journals (Sweden)

Regiec Piotr

2015-03-01

Full Text Available Ultrafiltration of diffusion juice is a method that can reduce environmental pollution during the production of sugar. A by-product (concentrate of ultrafiltration contains a large amount of sucrose, but due to its properties, it is difficult to manage. The aim of this study was to determine the effects of the temperature used during drying of diffusion juice concentrates on the content of certain components and characteristics of resultant preparations. Diffusion juice obtained from one of the Polish sugar plants was subjected to ultrafiltration and the obtained concentrates were dried in a spray dryer. In the dried samples, the following parameters were analyzed: dry mass, sucrose, total ash, protein, crude fiber and color. It has been declared that the degree of concentration and drying temperature influenced the chemical composition and the properties of the dehydrated diffusion juice concentrates. An increase in drying temperature was accompanied by the increased content of dry mass, protein, ash and fiber content in the preparations. The greater the degree of juice concentration, the greater was the content of dry mass, ash, and fiber. Inversely, the greater the degree of juice concentration, the lower the content of sucrose. The brightest color of the dehydrated product was observed at the drying temperature of 200°C. Spray-drying may be used for waste management after the diffusion juice membrane filtration, and the resultant preparations might be used in the production of feedstuff or food industry in general e.g. as sucrose source, in fermentation processes or in microorganisms propagation.

Experimental and computational investigation of polyacrylonitrile ultrafiltration membrane for industrial oily wastewater treatment

International Nuclear Information System (INIS)

Adib Hooman; Hassanajili, Shadi; Sheikhi-Kouhsar, Mohammad Reza; Salahi, Abdolhamid; Mohammadi, Toraj

2015-01-01

An experimental study on separation of industrial oil from oily wastewater has been done. A polyacrylonitrile membrane with a molecular weight cut-off (MWCO) of 20 kDa was used and an outlet wastewater of API unit of Tehran refinery was employed. The main purpose of this study was to develop a support vector machine model for permeation flux decline and fouling resistance in a cross-flow hydrophilic polyacrylonitrile membrane during ultrafiltration. The operating conditions which have been applied to develop a support vector machine model were transmembrane pressure (TMP), operating temperature, cross flow velocity (CFV), pH values of oily wastewater, permeation flux decline and fouling resistance. The testing results obtained by the support vector machine models are in very good agreement with experimental data. The calculated squared correlation coefficients for permeation flux decline and fouling resistance were both 0.99. Based on the results, the support vector machine proved to be a reliable accurate estimation method

Experimental and computational investigation of polyacrylonitrile ultrafiltration membrane for industrial oily wastewater treatment

Energy Technology Data Exchange (ETDEWEB)

Adib Hooman; Hassanajili, Shadi; Sheikhi-Kouhsar, Mohammad Reza [Shiraz University, Shiraz (Iran, Islamic Republic of); Salahi, Abdolhamid; Mohammadi, Toraj [Iran University of Science and Technology (IUST), Tehran (Iran, Islamic Republic of)

2015-01-15

An experimental study on separation of industrial oil from oily wastewater has been done. A polyacrylonitrile membrane with a molecular weight cut-off (MWCO) of 20 kDa was used and an outlet wastewater of API unit of Tehran refinery was employed. The main purpose of this study was to develop a support vector machine model for permeation flux decline and fouling resistance in a cross-flow hydrophilic polyacrylonitrile membrane during ultrafiltration. The operating conditions which have been applied to develop a support vector machine model were transmembrane pressure (TMP), operating temperature, cross flow velocity (CFV), pH values of oily wastewater, permeation flux decline and fouling resistance. The testing results obtained by the support vector machine models are in very good agreement with experimental data. The calculated squared correlation coefficients for permeation flux decline and fouling resistance were both 0.99. Based on the results, the support vector machine proved to be a reliable accurate estimation method.

Characterization of a non-fouling ultrafiltration membrane

DEFF Research Database (Denmark)

Wei, J.; Helm, G.S.; Corner-Walker, N.

2006-01-01

This report describes the properties of surface-modified poly(vinylidene fluoride) (PVDF) membranes. These membranes were created by coating hydrophilic polymers on the support PVDF membrane to reduce the tendency to protein fouling. The modified membranes with different molecular weight cut......-off (MWCO) were characterized by filtration studies using bovine serum albumin (BSA) and an enzyme solution as test media, and the membranes exhibited the non-fouling property. The surface chemistry of the unmodified and modified PVDF membranes was characterized by X-ray photoelectron spectroscopy (XPS......) and time-of-flight secondary ion mass spectroscopy (ToF-SIMS). These surface sensitive techniques were used to confirm the successful surface modification. ToF-SIMS imaging visualizes the distribution of the coating layer on the PVDF membrane. Furthermore, the amount of protein adsorption onto the membrane...

Modified forelimb grip strength test detects aging-associated physiological decline in skeletal muscle function in male mice.

Science.gov (United States)

Takeshita, Hikari; Yamamoto, Koichi; Nozato, Satoko; Inagaki, Tadakatsu; Tsuchimochi, Hirotsugu; Shirai, Mikiyasu; Yamamoto, Ryohei; Imaizumi, Yuki; Hongyo, Kazuhiro; Yokoyama, Serina; Takeda, Masao; Oguro, Ryosuke; Takami, Yoichi; Itoh, Norihisa; Takeya, Yasushi; Sugimoto, Ken; Fukada, So-Ichiro; Rakugi, Hiromi

2017-02-08

The conventional forelimb grip strength test is a widely used method to assess skeletal muscle function in rodents; in this study, we modified this method to improve its variability and consistency. The modified test had lower variability among trials and days than the conventional test in young C57BL6 mice, especially by improving the variabilities in male. The modified test was more sensitive than the conventional test to detect a difference in motor function between female and male mice, or between young and old male mice. When the modified test was performed on male mice during the aging process, reduction of grip strength manifested between 18 and 24 months of age at the group level and at the individual level. The modified test was similar to the conventional test in detecting skeletal muscle dysfunction in young male dystrophic mice. Thus, the modified forelimb grip strength test, with its improved validity and reliability may be an ideal substitute for the conventional method.

More Efficient Sodium Removal by Ultrafiltration Compared to Diuretics in Acute Heart Failure; Underexplored and Overstated.

Science.gov (United States)

Kazory, Amir

2016-01-01

Enhanced removal of sodium has often been cited as an advantage of ultrafiltration (UF) therapy over diuretic-based medical treatment in the management of acute decompensated heart failure. However, so far clinical studies have rarely evaluated the precise magnitude of sodium removal, and this assumption is largely based on the physiologic mechanisms and anecdotal observations that predate the contemporary management of heart failure. Recent data suggest that patients treated with UF experience substantial reduction in urinary sodium excretion possibly due to prolonged intravascular volume contraction. Consequently, the efficient sodium extraction through production of isotonic ultrafiltrate can be offset by urine hypotonicity. Based on the limited currently available data, it seems unlikely that the persistent benefits of UF could be solely explained by its greater efficiency in sodium removal. The design of the future studies should include frequent measurements of urine sodium to precisely compare the impact of UF and diuretics on sodium balance. © 2016 S. Karger AG, Basel.

Investigations of torrefied biomass grindability using a modified Hardgrove test

OpenAIRE

Tymoszuk Mateusz

2017-01-01

This paper presents results of investigations of torrefied biomass grindability using a modified Hardgrove test. The following types of torrefied biomass were used during the testing: alder chips, palm kernel shells and willow chips. Tests were conducted in a standard Hardgrove test mill for 50 cm3 volumetric samples (the same volume as applied in [1]). Volumetric samples of raw biomass were also tested for comparison purposes. Two ranges of the sample particle size were applied during the in...

Analysis of ultrafiltration failure in peritoneal dialysis patients by means of standard peritoneal permeability analysis.

Science.gov (United States)

Ho-dac-Pannekeet, M M; Atasever, B; Struijk, D G; Krediet, R T

1997-01-01

Ultrafiltration failure (UFF) is a complication of peritoneal dialysis (PD) treatment that occurs especially in long-term patients. Etiological factors include a large effective peritoneal surface area [measured as high mass transfer area coefficient (MTAC) of creatinine], a high effective lymphatic absorption rate (ELAR), a large residual volume, or combinations. The prevalence and etiology of UFF were studied and the contribution of transcellular water transport (TCWT) was analyzed. A new definition of UFF and guidelines for the analysis of its etiology were derived from the results. Peritoneal dialysis unit in the Academic Medical Center in Amsterdam. Cross-sectional study of standard peritoneal permeability analyses (4-hr dwells, dextran 70 as volume marker) with 1.36% glucose in 68 PD patients. Patients with negative net UF (change in intraperitoneal volume, dIPV rate (TCUFR) were lower (p lower residual volume (p = 0.03), and lower TCUFR (p = 0.01). Ultrafiltration failure was associated with a high MTAC creatinine in 3 patients, a high ELAR in 4 patients, and a combination of factors in one. As an additional possible cause, TCWT was studied, using the sodium gradient in the first hour of the dwell, corrected for diffusion (dNA). Five patients had dNA > 5 mmol/L, indicating normal TCWT. The 3 patients with dNA lower TCUFR (p = 0.04). A smaller difference was found between dIPV 3.86% and 1.36% (p = 0.04) compared to the dNA > 5 mmol/L group, but no differences were present for MTAC creatinine, ELAR, residual volume, or glucose absorption. In addition to known factors, impairment of TCWT can be a cause of UFF. A standardized dwell with 1.36% glucose overestimates UFF. Therefore, 3.86% glucose should be used for identification of patients with UFF, especially because it provides additional information on TCWT. Ultrafiltration failure can be defined as net UF exchange.

Analysis of alcohol dehydrogenase inhibitors from Desmodium styracifolium using centrifugal ultrafiltration coupled with HPLC-MS

Directory of Open Access Journals (Sweden)

Liu Liangliang

2015-01-01

Full Text Available Alcohol dehydrogenase (ADH inhibitors play an important role in the treatment of human methanol or ethylene glycol poisoning and the suppression of acetaldehyde accumulation in alcoholics. In this study, centrifugal ultrafiltration coupled with high performance liquid chromatography-mass spectrometry (HPLC-MS was utilized to screen and identify ADH inhibitors from ethyl acetate extract of Desmosium styracifolium (Osb. Merr. The experiment conditions of centrifugal ultrafiltration were optimized. At the optimum conditions (ADH concentration: 37.5 μg mL-1, incubation time: 90 min, pH: 7.0 and temperature: 15°C, formononetin and aromadendrin were successfully screened and identified from ethyl acetate extract of Desmodium styracifolium. The screening result was verified by ADH inhibition assays. The IC50 values of formononetin and aromadendrin were 70.8 and 84.7 μg mL-1, which were accorded with the binding degrees of them. Aromadendrin was first reported to have inhibitory activity on ADH. This method provided an effective way to screen active compounds from natural products.

Effect of PAC addition on immersed ultrafiltration for the treatment of algal-rich water

Energy Technology Data Exchange (ETDEWEB)

Zhang Yan, E-mail: zhang.yan113@163.com [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090 (China); Tian Jiayu; Nan Jun; Gao Shanshan; Liang Heng; Wang Meilian; Li Guibai [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090 (China)

2011-02-28

The aim of this study was to evaluate the effect of powdered activated carbon (PAC) addition on the treatment of algal-rich water by immersed ultrafiltration (UF), in terms of permeate quality and membrane fouling. Experiments were performed with a hollow-fiber polyvinyl chloride ultrafiltration membrane at a laboratory scale, 20-25 deg, C and 10 L/(m{sup 2} h) constant permeate flux. UF could achieve an absolute removal of Microcystis aeruginosa cells, but a poor removal of algogenic organic matter (AOM) released into water, contaminants responsible for severe membrane fouling. The addition of 4 g/L PAC to the immersed UF reactor significantly alleviated the development of trans-membrane pressure and enhanced the removal of dissovled organic carbon (by 10.9 {+-} 1.7%), UV{sub 254} (by 27.1 {+-} 1.7%), and microcystins (expressed as MC-LR{sub eq}, by 40.8 {+-} 4.2%). However, PAC had little effect on the rejection of hydrophilic high molecular weight AOM such as carbohydrates and proteins. It was also identified that PAC reduced the concentrations of carbohydrates and proteins in the reactor due to decreased light intensity, as well as the MC-LR{sub eq} concentration by PAC adsorption.

Carprofen pharmacokinetics in plasma and in control and inflamed canine tissue fluid using in vivo ultrafiltration.

Science.gov (United States)

Messenger, K M; Wofford, J A; Papich, M G

2016-02-01

Measurement of unbound drug concentrations at their sites of action is necessary for accurate PK/PD modeling. The objective of this study was to determine the unbound concentration of carprofen in canine interstitial fluid (ISF) using in vivo ultrafiltration and to compare pharmacokinetic parameters of free carprofen concentrations between inflamed and control tissue sites. We hypothesized that active concentrations of carprofen would exhibit different dispositions in ISF between inflamed vs. normal tissues. Bilateral ultrafiltration probes were placed subcutaneously in six healthy Beagle dogs 12 h prior to induction of inflammation. Two milliliters of either 2% carrageenan or saline control was injected subcutaneously at each probe site, 12 h prior to intravenous carprofen (4 mg/kg) administration. Plasma and ISF samples were collected at regular intervals for 72 h, and carprofen concentrations were determined using HPLC. Prostaglandin E2 (PGE2 ) concentrations were quantified in ISF using ELISA. Unbound carprofen concentrations were higher in ISF compared with predicted unbound plasma drug concentrations. Concentrations were not significantly higher in inflamed ISF compared with control ISF. Compartmental modeling was used to generate pharmacokinetic parameter estimates, which were not significantly different between sites. Terminal half-life (T½) was longer in the ISF compared with plasma. PGE2 in ISF decreased following administration of carprofen. In vivo ultrafiltration is a reliable method to determine unbound carprofen in ISF, and that disposition of unbound drug into tissue is much higher than predicted from unbound drug concentration in plasma. However, concentrations and pharmacokinetic parameter estimates are not significantly different in inflamed vs. un-inflamed tissues. © 2015 John Wiley & Sons Ltd.

Enhanced permeability and antifouling performance of cellulose acetate ultrafiltration membrane assisted by l-DOPA functionalized halloysite nanotubes.

Science.gov (United States)

Mu, Keguang; Zhang, Dalun; Shao, Ziqiang; Qin, Dujian; Wang, Yalong; Wang, Shuo

2017-10-15

l-Dopa functionalized halloysite nanotubes (HNTs) were prepared by the self-polymerization of l-dopa in the weak alkaline condition. Then different contents of l-dopa coated HNTs (LPDHNTs) were blended into cellulose acetate to prepare enhanced performance ultrafiltration membranes via the phase inversion method. The HNTs and LPDHNTs were characterized by FTIR, XPS, and TEM anysis. And the membranes morphologies, separation performance, antifouling performance, mechanical properties and hydrophilicity were also investigated. It was found that the composite membranes exhibited excellent antifouling performance. The pure water flux of 3.0wt% LPDHNTs/CA membrane increased from 11.4Lm -2 h -1 to 92.9Lm -2 h -1 , while the EA rejection ratio of the membrane was about 91.2%. In addition, the mechanical properties of the resultant membranes were strengthened compared with the CA ultrafiltration membrane. Copyright © 2017 Elsevier Ltd. All rights reserved.

Preparation and characterization of novel zwitterionic poly(arylene ether sulfone) ultrafiltration membrane with good thermostability and excellent antifouling properties

Science.gov (United States)

Rong, Guolong; Zhou, Di; Han, Xiaocui; Pang, Jinhui

2018-01-01

Zwitterionic poly(arylene ether sulfone) (PAES-NS) was synthesized via copolymerization by using a bisphenol monomer with a pyridine group. The chemical structures of the copolymers were confirmed by using Fourier transform infrared (FTIR) and 1H nuclear magnetic resonance (NMR) spectroscopy; the copolymers showed good thermal stability. A series of polyphenysulfone (PPSU)/PAES-NS blend ultrafiltration (UF) membranes was prepared via conventional immersion precipitation phase inversion methods The morphologies of the modified membranes were investigated by scanning electron microscopy (SEM). The surface hydrophilicity of the UF membranes was studied by water contact angle measurement, indicating that the zwitterionic group increased the membrane hydrophilicity. UF of solvated model pollutants using the membranes showed a significant reduction of the irreversible adsorption of the foulants, illustrating the excellent anti-fouling properties of the membrane. The water flux of the PAES-NS membrane was significantly enhanced, being almost three times higher than that of the pristine PPSU membrane, with retention of a high rejection level. After three UF cycles, the water flux recovery of the PAES-NS membrane was as high as 96%.

Preparation of antifouling ultrafiltration membranes via irradiation induced graft polymerization technique

International Nuclear Information System (INIS)

Deng Bo; Liu Zhognying; Lu Xiaofeng; Li Jingye; Yang Xuanxuan; Yu Ming; Zhang Bowu

2010-01-01

PVDF powders were irradiated in air at dose of 15 kGy by using gamma-rays. Macromolecular peroxides transformed from free radicals in the irradiated PVDF powders in air can be preserved for long-term at appropriate temperature stably. By mixing acrylic monomers with irradiated PVDF powders then the graft polymerization can be initiated by heating. Then a series of hydrophilic ultrafiltration (UF) membranes were fabricated by dissolving the PVDF-g-PAAc powders in the NMP under phase inversion method. The antifouling performances of UF membranes cast from virgin and grafted PVDF powders were compared. (authors)

Development and application of novelty pretreatment method for the concurrent quantitation of eleven water-soluble B vitamins in ultrafiltrates after renal replacement therapy.

Science.gov (United States)

Wirkus, Dorota; Jakubus, Aleksandra; Owczuk, Radosław; Stepnowski, Piotr; Paszkiewicz, Monika

2017-02-01

Continous renal replacement therapy (CRRT) is particularly recommended for septic shock patients in intensive care units. The CRRT technique used most frequently is high volume continuous veno-venous haemofiltration. It provides a high rate of clearance of uremic toxins and inflammatory cytokines. However, it should also be taken into account that substances important for homeostasis may be concurrently unintentionally removed. Accordingly, water-soluble vitamins can be removed during continuous renal replacement therapy, and the estimate of the loss is critical to ensure appropriate supplementation. The aim of this work was to develop a simple methodology for a purification step prior to the LC-MS/MS determination of water-soluble vitamins in ultrafiltrate samples. For this purpose, two types of resin and a mix of resins were used as sorbents for the purification step. Moreover, parameters such as the amount of resin and the extraction time were optimized. The LC-MS/MS method was developed and validated for final determination of 11 vitamins. The results demonstrated the high purification capability of DEAE Sephadex resin with recoveries between 65 and 101% for water-soluble vitamins from ultrafiltrate samples. An optimized method was applied to assess the loss of B-group vitamins in patients after 24h of renal replacement therapy. The loss of vitamins B2, B6 pyridoxamine, B6 pyridoxal, B7, B1, and B5 in ultrafiltrates was similar in all patients. In the native ultrafiltrates, vitamins B6 pyridoxine, B9 and B12 were not detected. Copyright © 2016 Elsevier B.V. All rights reserved.

Ultrafiltration and Nanofiltration Multilayer Membranes Based on Cellulose

KAUST Repository

Livazovic, Sara

2016-06-09

Membrane processes are considered energy-efficient for water desalination and treatment. However most membranes are based on polymers prepared from fossil petrochemical sources. The development of multilayer membranes for nanofiltration and ultrafiltration, with thin selective layers of naturally available cellulose, has been hampered by the availability of non-aggressive solvents. We propose the manufacture of cellulose membranes based on two approaches: (i) silylation, coating from solutions in tetrahydrofuran, followed by solvent evaporation and cellulose regeneration by acid treatment; (ii) casting from solution in 1-ethyl-3-methylimidazolum acetate ([C2mim]OAc), an ionic liquid, followed by phase inversion in water. In the search for less harsh, greener membrane manufacture, the combination of cellulose and ionic liquid is of high interest. Due to the abundance of OH groups and hydrophilicity, cellulose-based membranes have high permeability and low fouling tendency. Membrane fouling is one of the biggest challenges in membrane industry and technology. Accumulation and deposition of foulants onto the surface reduce membrane efficiency and requires harsh chemical cleaning, therefore increasing the cost of maintenance and replacement. In this work the resistance of cellulose 5 membranes towards model organic foulants such as Suwanee River Humic Acid (SRHA) and crude oil have been investigated. Cellulose membrane was tested in this work for oil-water (o/w) separation and exhibited practically 100 % oil rejection with good flux recovery ratio and membrane resistivity. The influence of anionic, cationic and ionic surfactant as well as pH and crude oil concentration on oil separation was investigated, giving a valuable insight in experimental and operational planning.

Industrial testing of modified clay powders by the ''Permneft''' organization

Energy Technology Data Exchange (ETDEWEB)

Matytsyn, V I; Kosivchenko, A M; Ryabchenko, V I; Shishov, V A

1980-01-01

VNIIKRneft' has developed a modified clay powder based on Cherkask bentonite with one ton of solution resulting in 20-28 cubic meters of powder per TU 39-08-123-77 formula. The modification stems from the type of bentonite treatment used. Bentonite is used in the amount of 3-5% of the total mass and the treatment involves the use of 0.3% calcium soda, copolymer methacrylic acid with M-14VV methacrylate. These reagents induce processes of change within the clay. The carbonate-nitrate activity serves to penthiatize the clay particles and the reagent solution which accompany the process of coagulation in the polymer structure, and in turn, increases the incidence of viscosity in the newly emerging systems. Tests indicate that the use of modified clay powder enhances drill bit pass-through. The large quantity of drilling solution resulting from one ton of modified clay powder further enhances the practical aspects of this system and reduces overall expenditures for solution treatment and clay powder while permitting the reduction of expenditures for other chemical reagents. Such economic benefits have been confirmed by industrial testing.

A strategy for in vitro safety testing of nanotitania-modified textile products

International Nuclear Information System (INIS)

Roszak, Joanna; Stępnik, Maciej; Nocuń, Marek; Ferlińska, Magdalena; Smok-Pieniążek, Anna; Grobelny, Jarosław; Tomaszewska, Emilia; Wąsowicz, Wojciech; Cieślak, Małgorzata

2013-01-01

Highlights: • Commercially available TiO 2 /Ag nanomaterials (NMs) showed higher cytotoxic effect than TiO 2 NMs. • Both titania NMs in pristine form induced a weak genotoxic effect in in vitro studies. • Cytotoxic effect of textile materials modified with TiO 2 /Ag NMs depended on the mode of the fiber manufacturing. • The strategy of in vitro testing of textile materials modified with NMs was proposed. -- Abstract: Titanium dioxide nanomaterials are extensively used in many applications, also for modification of textile materials. Toxicological assessment of such textile materials is currently seldom performed, mainly because of lack of appropriate guidelines. The aim of the study was to assess cytotoxic and genotoxic potential of commercially available TiO 2 and TiO 2 /Ag NMs in pristine form as well as polypropylene fibers modified with the NMs. Both titania NMs showed a cytotoxic effect on BALB/3T3 clone A31 and V79 fibroblasts after 72-h exposure. Both NMs induced a weak genotoxic effect in comet assay, with TiO 2 /Ag being more active. In vitro micronucleus test on human lymphocytes revealed a weak mutagenic effect of both materials after 24 h of exposure. In contrast, no significant increase in micronuclei frequency was observed in the in vitro micronucleus test on V79 fibroblasts. The 24-h extracts prepared from polypropylene fibers modified with TiO 2 /Ag induced a cytotoxic effect on BALB/3T3 cells which strongly depended on the mode of the fibers manufacturing. The study presents a comprehensive approach to toxicity assessment of textile fibers modified with NMs. Proposed approach may form a good “starting point” for improved future testing strategies

A strategy for in vitro safety testing of nanotitania-modified textile products

Energy Technology Data Exchange (ETDEWEB)

Roszak, Joanna; Stępnik, Maciej; Nocuń, Marek; Ferlińska, Magdalena; Smok-Pieniążek, Anna [Nofer Institute of Occupational Medicine, 8 St Teresy St., 91-348 Łódź (Poland); Grobelny, Jarosław; Tomaszewska, Emilia [University of Lodz, Faculty of Chemistry, 163 Pomorska St, 90-236 Łódź (Poland); Wąsowicz, Wojciech [Nofer Institute of Occupational Medicine, 8 St Teresy St., 91-348 Łódź (Poland); Cieślak, Małgorzata, E-mail: cieslakm@iw.lodz.pl [Textile Research Institute, 118 Gdańska St., 90-520, Łódź (Poland)

2013-07-15

Highlights: • Commercially available TiO{sub 2}/Ag nanomaterials (NMs) showed higher cytotoxic effect than TiO{sub 2} NMs. • Both titania NMs in pristine form induced a weak genotoxic effect in in vitro studies. • Cytotoxic effect of textile materials modified with TiO{sub 2}/Ag NMs depended on the mode of the fiber manufacturing. • The strategy of in vitro testing of textile materials modified with NMs was proposed. -- Abstract: Titanium dioxide nanomaterials are extensively used in many applications, also for modification of textile materials. Toxicological assessment of such textile materials is currently seldom performed, mainly because of lack of appropriate guidelines. The aim of the study was to assess cytotoxic and genotoxic potential of commercially available TiO{sub 2} and TiO{sub 2}/Ag NMs in pristine form as well as polypropylene fibers modified with the NMs. Both titania NMs showed a cytotoxic effect on BALB/3T3 clone A31 and V79 fibroblasts after 72-h exposure. Both NMs induced a weak genotoxic effect in comet assay, with TiO{sub 2}/Ag being more active. In vitro micronucleus test on human lymphocytes revealed a weak mutagenic effect of both materials after 24 h of exposure. In contrast, no significant increase in micronuclei frequency was observed in the in vitro micronucleus test on V79 fibroblasts. The 24-h extracts prepared from polypropylene fibers modified with TiO{sub 2}/Ag induced a cytotoxic effect on BALB/3T3 cells which strongly depended on the mode of the fibers manufacturing. The study presents a comprehensive approach to toxicity assessment of textile fibers modified with NMs. Proposed approach may form a good “starting point” for improved future testing strategies.

Blood volume-monitored regulation of ultrafiltration in fluid-overloaded hemodialysis patients: study protocol for a randomized controlled trial

Directory of Open Access Journals (Sweden)

Hecking Manfred

2012-06-01

Full Text Available Abstract Background Data generated with the body composition monitor (BCM, Fresenius show, based on bioimpedance technology, that chronic fluid overload in hemodialysis patients is associated with poor survival. However, removing excess fluid by lowering dry weight can be accompanied by intradialytic and postdialytic complications. Here, we aim at testing the hypothesis that, in comparison to conventional hemodialysis, blood volume-monitored regulation of ultrafiltration and dialysate conductivity (UCR and/or regulation of ultrafiltration and temperature (UTR will decrease complications when ultrafiltration volumes are systematically increased in fluid-overloaded hemodialysis patients. Methods/design BCM measurements yield results on fluid overload (in liters, relative to extracellular water (ECW. In this prospective, multicenter, triple-arm, parallel-group, crossover, randomized, controlled clinical trial, we use BCM measurements, routinely introduced in our three maintenance hemodialysis centers shortly prior to the start of the study, to recruit sixty hemodialysis patients with fluid overload (defined as ≥15% ECW. Patients are randomized 1:1:1 into UCR, UTR and conventional hemodialysis groups. BCM-determined, ‘final’ dry weight is set to normohydration weight −7% of ECW postdialysis, and reached by reducing the previous dry weight, in steps of 0.1 kg per 10 kg body weight, during 12 hemodialysis sessions (one study phase. In case of intradialytic complications, dry weight reduction is decreased, according to a prespecified algorithm. A comparison of intra- and post-dialytic complications among study groups constitutes the primary endpoint. In addition, we will assess relative weight reduction, changes in residual renal function, quality of life measures, and predialysis levels of various laboratory parameters including C-reactive protein, troponin T, and N-terminal pro-B-type natriuretic peptide, before and after the first study

46 CFR 53.10-3 - Inspection and tests (modifies HG-500 through HG-540).

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Inspection and tests (modifies HG-500 through HG-540... tests (modifies HG-500 through HG-540). (a) The inspections required by HG-500 through HG-540 must be performed by the “Authorized Inspector” as defined in HG-515 of section IV of the ASME Boiler and Pressure...

Potassium hydroxide: an alternative reagent to perform the modified apt test.

Science.gov (United States)

Chicaiza, Henry; Hellstrand, Karl; Lerer, Trudy; Smith, Sharon; Sylvester, Francisco

2014-09-01

We tested the performance of potassium hydroxide (KOH) in the modified Apt test under different experimental conditions using sodium hydroxide as a positive control. Like sodium hydroxide, KOH differentiated fresh fetal and adult blood stains on a cloth but not dried blood. KOH may be used to perform the Apt test at the bedside. Copyright © 2014 Elsevier Inc. All rights reserved.

Diagnostic Efficacy of Modified Coagglutination Test in the Diagnosis of Human Brucellosis

Directory of Open Access Journals (Sweden)

Mohite S.T

2013-07-01

Full Text Available Background: Laboratory help is must for thediagnosis of human brucellosis due to proteanclinical manifestations. As culture is hazardous,time consuming and less sensitive, serologicaltests are preferred for the diagnosis. Aggluti-nation tests like Rose Bengal PlateTest (RBPT, Serum Agglutination tests (SAT,2-Mercaptoethanol test (2-ME that are com-monly employed for the diagnosis either lacksensitivity or specificity. Coombs test andBrucellacapt though are sensitive and specific,workout costly. Therefore, modifiedcoagglutination test was developed and its di-agnostic efficacy was evaluated. Aims and Ob-jectives: To develop modified coagglutinationtest for the diagnosis of human brucellosis andcompare it with Coombs test. Materials andMethods: Serum samples collected from 191brucellosis patients and 100 controls were sub-jected to 2-ME, Coombs test and modifiedcoagglutination test (MCOAG. Blood culturewas performed by Castaneda’s method in all thepatients. Results: Significant difference in thepositivity rate was seen between MCOAG and2-ME. The results of MCOAG were compa-rable with Coombs test. Conclusions: Modi-fied coagglutination test is a better option toCoombs test for the serodiagnosis of brucel-losis in resource constrained countries as it issensitive, specific and cost effective.

Analysis of the prevalence and causes of ultrafiltration failure during long-term peritoneal dialysis: a cross-sectional study

NARCIS (Netherlands)

Smit, Watske; Schouten, Natalie; van den Berg, Nicole; Langedijk, Monique J.; Struijk, Dirk G.; Krediet, Raymond T.

2004-01-01

BACKGROUND: Ultrafiltration failure (UFF) is a major complication of peritoneal dialysis (PD). It can occur at any stage of PD, but develops in time and is, therefore, especially important in long-term treatment. To investigate its prevalence and to identify possible causes, we performed a

Determining fracture energy parameters of concrete from the modified compact tension test

Directory of Open Access Journals (Sweden)

A. Fernández-Canteli

2014-10-01

Full Text Available The modified compact tension (MCT test, though not yet recognized as a valid test for determining fracture energy of concrete, is believed to represent a plausible and suitable alternative versus other well established procedures, such as the wedge-splitting test (WST and the three point (3PB or four point bending (4PB tests, due to its simplicity and low cost. The aim of the paper is twofold: Firstly, to demonstrate the necessary correspondence between the experimental MCT test setup and finite element simulations and secondly, to initiate the way of establishing the desirable conversion between the fracture energy parameter values resulting from the MCT test and the standard conventional procedures. MCT tests are carried out and compared with the numerical results from 2-D and 3-D finite element calculations using the commercial codes ABAQUS and ATENA, the latter being specifically developed for applications on concrete structures and elements. In this way, the usability of the modified compact tension test for practical purposes is confirmed.

Modifying and Pilot Testing the Pap Smear Belief Questionnaire

Directory of Open Access Journals (Sweden)

Kelly Ackerson

2014-12-01

Full Text Available This study is a report on modifications and pilot testing of a measurement tool to predict Pap testing based on the Interaction Model of Client Health Behavior. Women have been found to avoid routine cervical cancer screening (CCS due to personal influencing factors. For this study, the Pap Smear Belief Questionnaire (PSBQ was modified by adding items and evaluated through content validity index (CVI = .89 and cognitive interviews (think-aloud protocol, resulting in a 31-item instrument with four subscales (Benefits, Barriers, Vulnerability, Experiences. Pilot testing the modified PSBQ was conducted at a local agency. Fifty-three women completed and returned the PSBQ, which had good internal consistency, with a Cronbach’s alpha coefficient of .81 (Benefits α = .51; Barriers α = .85; Vulnerability α = .78; Experiences α = .87. Test–retest reliability of the 31-item PSBQ was also good (.878. Univariate logistic regression indicated that the only significant predictor of seeking/avoiding routine screening by women’s background characteristics was social influence (p = .04. Subscales found to be significant predictors in Pap testing were Barriers (p = .003 and Gynecological Exam Experiences (p = .04. The refined 31-item PSBQ has good psychometric data supporting its use in predicting CCS. However, this research should be replicated in a larger sample enabling further validity and reliability testing of the PSBQ. Understanding women’s attitudes toward CCS will help health care providers, who deal with gynecological health, develop more effective screening programs and interventions facilitating better experiences for women contributing to an increase in routine screening.

Study of the binding of {sup 114m}In radiotracer to human serum components by ultrafiltration and chromatography

Energy Technology Data Exchange (ETDEWEB)

Hulle, M. van; De Cremer, K.; Cornelis, R. [Ghent Rijksuniversiteit (Belgium). Lab. for Analytical Chemistry

2000-10-01

The chemical speciation of indium in serum was studied. Ultrafiltration was used to investigate the influence of several buffer systems on the binding characteristics of indium in serum and to study the association of indium with transferrin and albumin. This was performed by means of batch incubation experiments with a {sup 114m}In tracer. Different buffer systems were investigated. A series of bicarbonate, Tris:HCl and HEPES buffers were found to fit for this purpose. Phosphate buffer was not suitable, as it is capable of disrupting the binding between indium and transferrin. Batch ultrafiltration experiments with {sup 114m}In incubated solutions of transferrin and albumin showed that both proteins are capable of binding indium to a high degree. Three chromatographic techniques (SEC, AEC, AC) were used to study the different chemically active species of indium in serum. It is concluded that next to transferrin, albumin is also responsible for the binding and transport of indium in serum. (orig.)

Determination of moxifloxacin in human plasma, plasma ultrafiltrate, and cerebrospinal fluid by a rapid and simple liquid chromatography- tandem mass spectrometry method.

Science.gov (United States)

Pranger, Arianna D; Alffenaar, Jan-Willem C; Wessels, A Mireille A; Greijdanus, Ben; Uges, Donald R A

2010-04-01

Moxifloxacin (MFX) is a useful agent in the treatment of multi-drug-resistant tuberculosis (MDR-TB). At Tuberculosis Centre Beatrixoord, a referral center for tuberculosis in the Netherlands, approximately 36% of the patients have received MFX as treatment. Based on the variability of MFX AUC, the variability of in vitro susceptibility to MFX of M. tuberculosis, and the variability of penetration into sanctuary sites, measuring the concentration of MFX in plasma and cerebrospinal fluid (CSF) could be recommended. Therefore, a rapid and validated liquid chromatography-tandem mass spectrometry (LC-MS-MS) analyzing method with a simple pretreatment procedure was developed for therapeutic drug monitoring of MFX in human plasma and CSF. Because of the potential influence of protein binding on efficacy, we decided to determine both bound and unbound (ultrafiltrate) fraction of MFX. The calibration curves were linear in the therapeutic range of 0.05 to 5.0 mg/L plasma and CSF with CV in the range of -5.4% to 9.3%. MFX ultrafiltrate samples could be determined with the same method setup for analysis of MFX in CSF. The LC-MS-MS method developed in this study is suitable for monitoring MFX in human plasma, plasma ultrafiltrate, and CSF.

Modify beam transversal test to evaluate hemiparkinsonian rats

International Nuclear Information System (INIS)

Blanco Lezcano, Lissette; Lorigados Pedre, Lourdes del C; Fernandez Verdecia, Caridad I; Serrano Sanchez, Teresa; Pavon Fuentes, Nancy; Turner, Liliana Francis

2010-01-01

The nigrostriatal degeneration underlying Parkinson's disease (PD) is commonly studied in experimental animals by injection of the neurotoxin 6-hydroxydopamine. the present study describes a modified version of a beam traversal test which allows the quantification of the motor deficit through the time spent to arrive to the platform once all four paws of the animals are in contact with the beam (escape latency, el), the time spent before falling (tumbled down latency, TDL) and the number of errors (NE) committed for the animals in each beam. The shape and the diameter of the cross section of the beams were modified from rectangular and circular cross section with 2.5 cm of diameter to the same shape with 1 cm of diameter, which induced a high difficulty to the execution of the test. Three groups of Wistar rats were examined: untreated (n=15), lesioned with 6-hydroxydopamine (n=14), and sham-operated (n=14). All variables studied showed significant differences between control and hemiparkinsonian rats. The EL and the NE were increased and the TDL was decreased in hemiparkinsonian rats for all beams in comparison with control rats. In TDL the significant differences between groups were more evident (p<0.001) for the beams with high cross section irrespective of the shape of the cross section. BTT is a convenient sensorimotor test that does not need to be trained extensively, and require adverse motivation or food deprivation and appears to be very useful in evaluating the motor deficits in established unilateral model of PD and also other experimental models.

The effect of low-GDP solution on ultrafiltration and solute transport in continuous ambulatory peritoneal dialysis patients.

Science.gov (United States)

Cho, Kyu-Hyang; Do, Jun-Young; Park, Jong-Won; Yoon, Kyung-Woo; Kim, Yong-Lim

2013-01-01

Several studies have reported benefits for human peritoneal mesothelial cell function of a neutral-pH dialysate low in glucose degradation products (GDPs). However, the effects of low-GDP solution on ultrafiltration (UF), transport of solutes, and control of body water remain elusive. We therefore investigated the effect of low-GDP solution on UF, solute transport, and control of body water. Among 79 new continuous ambulatory peritoneal dialysis (CAPD) patients, 60 completed a 12-month protocol (28 in a lactate-based high-GDP solution group, 32 in a lactate-based low-GDP solution group). Clinical indices--including 24-hour UF volume (UFV), 24-hour urine volume (UV), residual renal function, and dialysis adequacy--were measured at months 1, 6, and 12. At months 1, 6, and 12, UFV, glucose absorption, 4-hour dialysate-to-plasma (D/P) creatinine, and 1-hour D/P Na(+) were assessed during a modified 4.25% peritoneal equilibration test (PET). Body composition by bioelectric impedance analysis was measured at months 1 and 12 in 26 CAPD patients. Daily UFV was lower in the low-GDP group. Despite similar solute transport and aquaporin function, the low-GDP group also showed lower UFV and higher glucose absorption during the PET. Factors associated with UFV during the PET were lactate-based high-GDP solution and 1-hour D/P Na(+). No differences in volume status and obesity at month 12 were observed, and improvements in hypervolemia were equal in both groups. Compared with the high-GDP group, the low-GDP group had a lower UFV during a PET and a lower daily UFV during the first year after peritoneal dialysis initiation. Although the low-GDP group had a lower daily UFV, no difficulties in controlling edema were encountered.

Unbound fraction of fluconazole and linezolid in human plasma as determined by ultrafiltration: Impact of membrane type.

Science.gov (United States)

Kratzer, Alexander; Kees, Frieder; Dorn, Christoph

2016-12-15

Ultrafiltration is a rapid and convenient method to determine the free concentrations of drugs in plasma. Several ultrafiltration devices based on Eppendorf cups are commercially available, but are not validated for such use by the manufacturer. Plasma pH, temperature and relative centrifugal force as well as membrane type can influence the results. In the present work, we developed an ultrafiltration method in order to determine the free concentrations of linezolid or fluconazole, both neutral and moderately lipophilic antiinfective drugs for parenteral as well as oral administration, in plasma of patients. Whereas both substances behaved relatively insensitive in human plasma regarding variations in pH (7.0-8.5), temperature (5-37°C) or relative centrifugal force (1000-10.000xg), losses of linezolid were observed with the Nanosep Omega device due to adsorption onto the polyethersulfone membrane (unbound fraction 75% at 100mg/L and 45% at 0.1mg/L, respectively). No losses were observed with Vivacon which is equipped with a membrane of regenerated cellulose. With fluconazole no differences between Nanosep and Vivacon were observed. Applying standard conditions (pH 7.4/37°C/1000xg/20min), the mean unbound fraction of linezolid in pooled plasma from healthy volunteers was 81.5±2.8% using Vivacon, that of fluconazole was 87.9±3.5% using Nanosep or 89.4±3.3% using Vivacon. The unbound fraction of linezolid was 85.4±3.7% in plasma samples from surgical patients and 92.1±6.2% in ICU patients, respectively. The unbound fraction of fluconazole was 93.9±3.3% in plasma samples from ICU patients. Copyright © 2016 Elsevier B.V. All rights reserved.

Organic fouling behavior of superhydrophilic polyvinylidene fluoride (PVDF) ultrafiltration membranes functionalized with surface-tailored nanoparticles: Implications for organic fouling in membrane bioreactors

KAUST Repository

Liang, Shuai; Qi, Genggeng; Xiao, Kang; Sun, Jianyu; Giannelis, Emmanuel P.; Huang, Xia; Elimelech, Menachem

2014-01-01

This study systematically investigates the organic fouling behavior of a superhydrophilic polyvinylidene fluoride (PVDF) ultrafiltration membrane functionalized via post-fabrication tethering of surface-tailored silica nanoparticles to poly

Extended testing of a modified 18B plutonium nitrate shipping container

International Nuclear Information System (INIS)

Yoshimura, H.R.; Pope, R.B.; Leisher, W.B.; Joseph, B.J.; Schulz-Forberg, B.; Hubner, H.W.

1980-01-01

The container damage observed as the result of the high-speed pulldown impact test was more severe than that of either the 185-m free-fall drop of a prototype container onto a semirigid surface or the crush environment produced by a 9-m drop of a 2-tonne block onto a modified container resting on an unyielding surface. In comparison to the extended tests, the 9-m regulatory drop test onto an unyielding surface of the prototype packaging in its most damaging orientation produced the least amount of damage. Very little deformation in the overpack was observed, and there was no influence on the fire resistivity and leaktightness of the containment vessel. The 128 m/s impact test produced a leak in the container. It appears that the 18B packaging, designed to withstand the environments specified in IAEA Safety Series No. 6, can withstand extended environments including longer duration fires and higher velocity impacts on yielding targets. When modified with ring stiffeners, the packaging withstood a dynamic crush test, but did not survive the high speed impact onto an unyielding surface as specified in NUREG 0360

Preparation and characterization of a novel PVDF ultrafiltration membrane by blending with TiO_2-HNTs nanocomposites

International Nuclear Information System (INIS)

Zeng, Guangyong; He, Yi; Yu, Zongxue; Zhan, Yingqing; Ma, Lan; Zhang, Lei

2016-01-01

Highlights: • A novel TiO_2-HNTs/PVDF ultrafiltration membrane was prepared. • TiO_2 dispersed well in membrane matrix by loading on the surface of HNTs. • The hydrophilicity of membrane was improved with the addition of TiO_2-HNTs. • TiO_2-HNTs/PVDF membranes showed good antifouling performance. - Abstract: Novel polyvinylidene fluoride (PVDF) ultrafiltration membranes were prepared by blending with different contents of titanium dioxide-halloysite nanotubes (TiO_2-HNTs) composites into the PVDF matrix. The effects of TiO_2-HNTs content on the membrane performances, such as hydrophilicity, rejection ratio and antifouling properties were investigated in detail. X-ray diffraction (XRD), thermo-gravimetric analyzer (TGA) and scanning electron microscope (SEM) analyses showed that TiO_2 was loaded on the surface of HNTs successfully and homogeneously by sol-gel method. The morphologies and microstructure of the membranes were characterized by SEM and atomic force microscopy (AFM). The contact angle (CA) tests indicated that the hydrophilicity of membranes was significantly increased with the addition of TiO_2-HNTs. The pure water flux of 3%TiO_2-HNTs/PVDF was increased by 264.8% and 35.6%, respectively, compared with pure PVDF membrane and 3%TiO_2/PVDF membrane, although the rejection of bovine serum albumin (BSA) was slightly decreased. More importantly, TiO_2-HNTs/PVDF membrane exhibited an excellent anti-fouling performance, which was attributed to the hydrophobic contaminants being resisted by hydrophilic nanoparticles. It can be expected that this work may provide some references to solve the dispersion of nanoparticle in the membrane and improve the anti-fouling performance of membrane in the field of wastewater treatment.

p-Nitrophenol removal by combination of powdered activated carbon adsorption and ultrafiltration - comparison of different operational modes.

Science.gov (United States)

Ivancev-Tumbas, Ivana; Hobby, Ralph; Küchle, Benjamin; Panglisch, Stefan; Gimbel, Rolf

2008-09-01

Ultrafiltration is classified as a low-pressure membrane technology which effectively removes particulate matter and microorganisms and to a certain extent dissolved organic matter (15-25%) and colour. The technology has been optimized and is becoming competitive compared to conventional processes for larger scale plant capacities. In combination with activated carbon it is an effective barrier regarding the removal of synthetic organic chemicals. Growing interest in ultrafiltration raises the question of better usage of the adsorption capacity of powdered activated carbon (PAC) used in combination with this low-pressure membrane technique. This paper presents a pilot plant study of different PAC dosing procedures within a combined hybrid membrane IN/OUT process for removal of p-nitrophenol (PNP) from water (c(0)=1mg/L) under real case conditions (e.g. usage of the same module for the whole duration of the experiment, backwashing with permeate water, no separate saturation of the membrane with substance without presence of carbon). p-Nitrophenol was chosen as an appropriate test substance to assess the efficiency of different operation modes. Dead-end and cross-flow filtration were compared with respect to different PAC dosing procedures: continuous dosing into a continuously stirred tank reactor (CSTR) in front of the module and direct dosing into the pipe in front of the module (continuous, single-pulse and multi-pulse dosing). There was no advantage in cross-flow mode over dead-end referring to PNP concentration in the permeate. Relating to the carbon dosing procedure, the best results were obtained for continuous PAC addition. The option of dosing directly into the pipe has the advantage of no additional tank being necessary. In the case of single-pulse dosing, the formation of a carbon layer on the membrane surface was assumed and an LDF model applied for a simplified estimation of the "breakthrough behaviour" in the thus formed "PAC filter layer".

Concentration of aqueous extracts of defatted soy flour by ultrafiltration; Effect of suspended particles on the filtration flux

NARCIS (Netherlands)

Noordman, T.R.; Kooiker, K.; Bel, W.; Dekker, M.; Wesselingh, J.A.

2003-01-01

Suspended particles can have a positive effect on the flux and concentration curve of soy flour extracts during ultrafiltration. This is described by a simple empirical model. The suspended particles in this study were insoluble milled bean material (mean particle size 25 m). It is shown that it is

EDTA fouling in dead-end ultrafiltration of low level radioactive wastewater

Energy Technology Data Exchange (ETDEWEB)

Niu, Lixia [Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC), Graduate School at Shenzhen, Tsinghua University, Shenzhen, 518055 (China); Zhang, Xue [Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Zhao, Xuan, E-mail: zhxinet@mail.tsinghua.edu.cn [Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Hu, Hongying [Environmental Simulation and Pollution Control State Key Joint Laboratory, School of Environment, Tsinghua University, Beijing 100084 (China); State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC), Graduate School at Shenzhen, Tsinghua University, Shenzhen, 518055 (China)

2015-12-15

Highlights: • EDTA in LLRW caused unrecoverable UF membrane fouling. • The rejection of nuclides by UF was significantly enhanced with EDTA addition. • The nuclide (except Ag) deposition on membrane increased with EDTA addition. • Reducing EDTA in the feed water or alkaline/ultrasonic washing were suggested. - Abstract: EDTA is widely used as a detergent, and finally enters into wastewater. The influence of EDTA on ultrafiltration of low level radioactive wastewater (LLRW) was investigated under different operation conditions. As the main organic pollutant, EDTA led to unrecoverable membrane fouling and the normalized flux decreased from 100% to 85% depending on its concentration. The clogging caused by EDTA increased the surface roughness of the membrane, leading to the flux reduction. Both nuclide rejections and depositions on the membrane surfaces were enhanced with EDTA addition, due to the strong complexation of the nuclides with EDTA. However, Ag deposition on the membrane decreased slightly in the presence of EDTA, which may be caused by the stronger attraction of Ag to the unmodified membrane than that to the EDTA-modified one. Transmembrane pressure (TMP) and molecular weight cut off (MWCO) of membranes had negligible effects on membrane fouling, while the nuclide rejections by membrane and the depositions of nuclides on membrane both decreased significantly when the TMP increased to 0.2 MPa and MWCO increased from 5 kDa to 30 kDa. Based on these results, it clearly showed that EDTA even at a low concentration had strong effects on the performance of UF treating LLRW. Therefore, it is suggested for industrial application that pretreatments to reduce EDTA or alkaline/ultrasonic washing involved in UF process were necessary to reduce the nuclide depositions on the membrane surfaces and irradiation dose of membrane surface.

Predicting optimal back-shock times in ultrafiltration hollow fiber modules II: Effect of inlet flow and concentration dependent viscosity

DEFF Research Database (Denmark)

Vinther, Frank; Pinelo, Manuel; Brøns, Morten

2015-01-01

This paper concerns mathematical modeling and computational fluid dynamics of back-shocking during hollow fibre ultrafiltration of dextran T500. In this paper we present a mathematical model based on first Principles, i.e., solving the Navier-Stokes equation along with the continuity equation...

Impact of ozonation, anion exchange resin and UV/H2O2 pre-treatments to control fouling of ultrafiltration membrane for drinking water treatment.

Science.gov (United States)

Pramanik, Biplob Kumar; Pramanik, Sagor Kumar; Sarker, Dipok Chandra; Suja, Fatihah

2017-06-01

The effects of ozonation, anion exchange resin (AER) and UV/H 2 O 2 were investigated as a pre-treatment to control organic fouling (OF) of ultrafiltration membrane in the treatment of drinking water. It was found that high molecular weight (MW) organics such as protein and polysaccharide substances were majorly responsible for reversible fouling which contributed to 90% of total fouling. The decline rate increased with successive filtration cycles due to deposition of protein content over time. All pre-treatment could reduce the foulants of a Ultrafiltration membrane which contributed to the improvement in flux, and there was a greater improvement of flux by UV/H 2 O 2 (61%) than ozonation (43%) which in turn was greater than AER (23%) treatment. This was likely due to the effective removal/breakdown of high MW organic content. AER gave greater removal of biofouling potential components (such as biodegradable dissolved organic carbon and assimilable organic carbon contents) compared to UV/H 2 O 2 and ozonation treatment. Overall, this study demonstrated the potential of pre-treatments for reducing OF of ultrafiltration for the treatment of drinking water.

Appropriateness of mechanistic and non-mechanistic models for the application of ultrafiltration to mixed waste

International Nuclear Information System (INIS)

Foust, Henry; Ghosehajra, Malay

2007-01-01

This study asks two questions: (1) How appropriate is the use of a basic filtration equation to the application of ultrafiltration of mixed waste, and (2) How appropriate are non-parametric models for permeate rates (volumes)? To answer these questions, mechanistic and non-mechanistic approaches are developed for permeate rates and volumes associated with an ultrafiltration/mixed waste system in dia-filtration mode. The mechanistic approach is based on a filtration equation which states that t/V vs. V is a linear relationship. The coefficients associated with this linear regression are composed of physical/chemical parameters of the system and based the mass balance equation associated with the membrane and associated developing cake layer. For several sets of data, a high correlation is shown that supports the assertion that t/V vs. V is a linear relationship. It is also shown that non-mechanistic approaches, i.e., the use of regression models to are not appropriate. One models considered is Q(p) = a*ln(Cb)+b. Regression models are inappropriate because the scale-up from a bench scale (pilot scale) study to full-scale for permeate rates (volumes) is not simply the ratio of the two membrane surface areas. (authors)

Application of pressure ultrafiltration in determining the binding capacity of drugs to human albumin and to plasma proteins of intact and irradiated rat females

International Nuclear Information System (INIS)

Zima, M.

1976-01-01

The significance of the binding of drugs to plasma proteins has repeatedly been demonstrated and draws the interest of many pharmacologists. The described experiments served to study the binding of isoniazid (INH) to human albumin of various dilution and to whole plasma proteins of irradiated (on the Oth, 3rd and 6th day after exposure to 154.8 mC/kg=600 R) and non-irradiated rats using the technique of modified accelerated ultrafiltration through cellophane. The total characteristics of the binding and its changes were demonstrated by the equilibrium constant, the numbers of binding sites and the changes of free binding energy. The results show that the dilution of human albumin affects the strength of the INH binding on this albumin and further that the normally weak INH binding is diminished even more in irradiated rats. This cannot be explained by the change in the percentage composition of the rat plasma. (author)

A risk-based classification scheme for genetically modified foods. II: Graded testing.

Science.gov (United States)

Chao, Eunice; Krewski, Daniel

2008-12-01

This paper presents a graded approach to the testing of crop-derived genetically modified (GM) foods based on concern levels in a proposed risk-based classification scheme (RBCS) and currently available testing methods. A graded approach offers the potential for more efficient use of testing resources by focusing less on lower concern GM foods, and more on higher concern foods. In this proposed approach to graded testing, products that are classified as Level I would have met baseline testing requirements that are comparable to what is widely applied to premarket assessment of GM foods at present. In most cases, Level I products would require no further testing, or very limited confirmatory analyses. For products classified as Level II or higher, additional testing would be required, depending on the type of the substance, prior dietary history, estimated exposure level, prior knowledge of toxicity of the substance, and the nature of the concern related to unintended changes in the modified food. Level III testing applies only to the assessment of toxic and antinutritional effects from intended changes and is tailored to the nature of the substance in question. Since appropriate test methods are not currently available for all effects of concern, future research to strengthen the testing of GM foods is discussed.

Modified alignment CGHs for aspheric surface test

Science.gov (United States)

Song, Jae-Bong; Yang, Ho-Soon; Rhee, Hyug-Gyo; Lee, Yun-Woo

2009-08-01

Computer Generated Holograms (CGH) for optical test are commonly consisted of one main pattern for testing aspheric surface and some alignment patterns for aligning the interferometer, CGH, and the test optics. To align the CGH plate and the test optics, we designed the alignment CGHs modified from the cat's eye alignment method, which are consisted of a couple of CGH patterns. The incident beam passed through the one part of the alignment CGH pattern is focused onto the one radius position of the test aspheric surface, and is reflected to the other part, and vice versa. This method has several merits compared to the conventional cat's eye alignment method. First, this method can be used in testing optics with a center hole, and the center part of CGH plate can be assigned to the alignment pattern. Second, the alignment pattern becomes a concentric circular arc pattern. The whole CGH patterns including the main pattern and alignment patterns are consisted of only concentric circular fringes. This concentric circular pattern can be easily made by the polar coordinated writer with circular scanning. The required diffraction angle becomes relatively small, so the 1st order diffraction beams instead of the 3rd order diffraction beam can be used as alignment beams, and the visibility can be improved. This alignment method also is more sensitive to the tilt and the lateral shift of the test aspheric surface. Using this alignment pattern, a 200 mm diameter F/0.5 aspheric mirror and a 600 mm diameter F/0.9 mirror were tested.

Study on cross-flow ultrafiltration for the radioactive liquid waste treatment

International Nuclear Information System (INIS)

Jung, K. H.; Jo, E. S.; Lee, D. G.; Lee, G. W.; Jung, K. J.

2000-01-01

The effect of the UF membranes on permeate flux was investigated in the ultrafiltration of dodecane (0.1v%) / water emulsion and dodecane-SDS-water emulsion in view of the treatment of radioactive oily emulsion liquid waste in the future. For variety of membranes, experiments in cross-flow modes have been performed at various pressure and different cross-flow velocities. Permeate flux decreased with the time and reached a constant steady-state value. Steady-state flux was found to be dependent by the hydrodynamic conditions but independent by the pressure. Flux decrease and rates of permeate flow resistance change have been analysed using a formulation of the equations illustrating the method of resistance mechanism recognition

Hollow fiber membrane ultrafiltration of a simulated secondary treatment wastewater. Process and fouling modeling

OpenAIRE

Soler Cabezas, José Luis; Vincent Vela, Maria Cinta; Mendoza Roca, José Antonio; Martínez Francisco, Francisco Juan

2012-01-01

It is well known that there is a scarcity of drinking and irrigation water around the world nowadays. According to the United Nations, water scarcity affects 1.2 billion people (one-fifth of the world's population) and the water use has been growing at twice the rate of population increase in the last century. This fact makes the reuse of the wastewater from municipal wastewater treatment plants (MWTPs) an interesting option. Ultrafiltration after the secondary settling is becoming more f...

The modified Thomas test is not a valid measure of hip extension unless pelvic tilt is controlled

Directory of Open Access Journals (Sweden)

Andrew D. Vigotsky

2016-08-01

Full Text Available The modified Thomas test was developed to assess the presence of hip flexion contracture and to measure hip extensibility. Despite its widespread use, to the authors’ knowledge, its criterion reference validity has not yet been investigated. The purpose of this study was to assess the criterion reference validity of the modified Thomas test for measuring peak hip extension angle and hip extension deficits, as defined by the hip not being able to extend to 0º, or neutral. Twenty-nine healthy college students (age = 22.00 ± 3.80 years; height = 1.71 ± 0.09 m; body mass = 70.00 ± 15.60 kg were recruited for this study. Bland–Altman plots revealed poor validity for the modified Thomas test’s ability to measure hip extension, which could not be explained by differences in hip flexion ability alone. The modified Thomas test displayed a sensitivity of 31.82% (95% CI [13.86–54.87] and a specificity of 57.14% (95% CI [18.41–90.10] for testing hip extension deficits. It appears, however, that by controlling pelvic tilt, much of this variance can be accounted for (r = 0.98. When pelvic tilt is not controlled, the modified Thomas test displays poor criterion reference validity and, as per previous studies, poor reliability. However, when pelvic tilt is controlled, the modified Thomas test appears to be a valid test for evaluating peak hip extension angle.

Concentration of lemon pectin extract by ultrafiltration

Directory of Open Access Journals (Sweden)

Damián Stechina

2012-09-01

Full Text Available Current annual lemon production in Argentina is about 900 thousand t. 75% is used industrially to obtain pasteurized juice concentrate. Since 40 - 45 % of citrus fruit content is peel and seeds, the annual lemon residue yield is 360 thousand t. Lemon peel contains about 30% (B.S. of peptic substances with an important commercial value due to its gelling and thickening properties for food, chemical, pharmacological and cosmetic products. Membrane processes have many applications in food manufacture. The objective of this study is to analyze the influence of ultrafiltration operating variables on instant permeate flow (Fp and on the energy requirement for pectin extract concentration from lemon peel. A DDS lab module was used, lab 20-772 model with synthetic material membranes, 9 kDa, shear force, the intrinsic membrane resistance (Rm being 3*1013 m -1 . Results show that Fp decrease caused by polarization induced resistance occurrence and the influence of operating variables on Fp offer relevant data to estimate the energy requirement in relation to feeding flow at constant temperature, which may be compared to pectin concentration increase in the retained flow in relation to initial extract concentration.

Laboratory Tests on Post-Filtration Precipitation in the WTP Pretreatment Process

International Nuclear Information System (INIS)

Russell, Renee L.; Peterson, Reid A.; Rinehart, Donald E.; Crum, Jarrod V.

2009-01-01

Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed, and operated as part of a plan to respond to issue M12, 'Undemonstrated Leaching Processes,' of the External Flowsheet Review Team (EFRT) issue response plan (Barnes et al. 2006). The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. A simplified flow diagram of the PEP system is shown in Figure 1.1. Two operating scenarios are currently being evaluated for the ultrafiltration process (UFP) and leaching operations. The first scenario has caustic leaching performed in the UFP-2 ultrafiltration feed vessels (i.e., vessel UFP-VSL-T02A in the PEP; and vessels UFP-VSL-00002A and B in the WTP PTF). The second scenario has caustic leaching conducted in the UFP-1 ultrafiltration feed preparation vessels (i.e., vessels UFP-VSL-T01A and B in the PEP; vessels UFP-VSL-00001A and B in the WTP PTF).

Industrial Tests to Modify Molten Copper Slag for Improvement of Copper Recovery

Science.gov (United States)

Guo, Zhengqi; Zhu, Deqing; Pan, Jian; Zhang, Feng; Yang, Congcong

2018-04-01

In this article, to improve the recovery of copper from copper slag by flotation process, industrial tests of the modification process involving addition of a composite additive into molten copper slag were conducted, and the modified slag was subjected to the flotation process to confirm the modification effect. The phase evolution of the slag in the modification process was revealed by thermodynamic calculations, x-ray diffraction, optical microscopy and scanning electron microscopy. The results show that more copper was transformed and enriched in copper sulfide phases. The magnetite content in the modified slag decreased, and that of "FeO" increased correspondingly, leading to a better fluidity of the molten slag, which improved the aggregation and growth of fine particles of the copper sulfide minerals. Closed-circuit flotation tests of the original and modified slags were conducted, and the results show that the copper recovery increased obviously from 69.15% to 73.38%, and the copper grade of concentrates was elevated slightly from 20.24% to 21.69%, further confirming that the industrial tests of the modification process were successful. Hence, the modification process has a bright future in industrial applications for enhancing the recovery of copper from the copper slag.

Modified Distribution-Free Goodness-of-Fit Test Statistic.

Science.gov (United States)

Chun, So Yeon; Browne, Michael W; Shapiro, Alexander

2018-03-01

Covariance structure analysis and its structural equation modeling extensions have become one of the most widely used methodologies in social sciences such as psychology, education, and economics. An important issue in such analysis is to assess the goodness of fit of a model under analysis. One of the most popular test statistics used in covariance structure analysis is the asymptotically distribution-free (ADF) test statistic introduced by Browne (Br J Math Stat Psychol 37:62-83, 1984). The ADF statistic can be used to test models without any specific distribution assumption (e.g., multivariate normal distribution) of the observed data. Despite its advantage, it has been shown in various empirical studies that unless sample sizes are extremely large, this ADF statistic could perform very poorly in practice. In this paper, we provide a theoretical explanation for this phenomenon and further propose a modified test statistic that improves the performance in samples of realistic size. The proposed statistic deals with the possible ill-conditioning of the involved large-scale covariance matrices.

Preparation and characterization of a novel PVDF ultrafiltration membrane by blending with TiO{sub 2}-HNTs nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Zeng, Guangyong [College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); Oil & Gas Field Applied Chemistry Key Laboratory of Sichuan Province, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); He, Yi, E-mail: heyi@swpu.edu.cn [College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); Oil & Gas Field Applied Chemistry Key Laboratory of Sichuan Province, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); State Key Laboratory of Oil & Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); Yu, Zongxue; Zhan, Yingqing; Ma, Lan [College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); Oil & Gas Field Applied Chemistry Key Laboratory of Sichuan Province, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); Zhang, Lei, E-mail: zgc166929@sohu.com [College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); Oil & Gas Field Applied Chemistry Key Laboratory of Sichuan Province, Southwest Petroleum University, Chengdu, Sichuan 610500 (China)

2016-05-15

Highlights: • A novel TiO{sub 2}-HNTs/PVDF ultrafiltration membrane was prepared. • TiO{sub 2} dispersed well in membrane matrix by loading on the surface of HNTs. • The hydrophilicity of membrane was improved with the addition of TiO{sub 2}-HNTs. • TiO{sub 2}-HNTs/PVDF membranes showed good antifouling performance. - Abstract: Novel polyvinylidene fluoride (PVDF) ultrafiltration membranes were prepared by blending with different contents of titanium dioxide-halloysite nanotubes (TiO{sub 2}-HNTs) composites into the PVDF matrix. The effects of TiO{sub 2}-HNTs content on the membrane performances, such as hydrophilicity, rejection ratio and antifouling properties were investigated in detail. X-ray diffraction (XRD), thermo-gravimetric analyzer (TGA) and scanning electron microscope (SEM) analyses showed that TiO{sub 2} was loaded on the surface of HNTs successfully and homogeneously by sol-gel method. The morphologies and microstructure of the membranes were characterized by SEM and atomic force microscopy (AFM). The contact angle (CA) tests indicated that the hydrophilicity of membranes was significantly increased with the addition of TiO{sub 2}-HNTs. The pure water flux of 3%TiO{sub 2}-HNTs/PVDF was increased by 264.8% and 35.6%, respectively, compared with pure PVDF membrane and 3%TiO{sub 2}/PVDF membrane, although the rejection of bovine serum albumin (BSA) was slightly decreased. More importantly, TiO{sub 2}-HNTs/PVDF membrane exhibited an excellent anti-fouling performance, which was attributed to the hydrophobic contaminants being resisted by hydrophilic nanoparticles. It can be expected that this work may provide some references to solve the dispersion of nanoparticle in the membrane and improve the anti-fouling performance of membrane in the field of wastewater treatment.

Novel cellobiose 2-epimerases for the production of epilactose from milk ultrafiltrate containing lactose.

Science.gov (United States)

Krewinkel, Manuel; Kaiser, Jana; Merz, Michael; Rentschler, Eva; Kuschel, Beatrice; Hinrichs, Jörg; Fischer, Lutz

2015-06-01

A selected number of enzymes have recently been assigned to the emerging class of cellobiose 2-epimerases (CE). All CE convert lactose to the rare sugar epilactose, which is regarded as a new prebiotic. Within this study, the gene products of 2 potential CE genes originating from the mesophilic bacteria Cellulosilyticum lentocellum and Dysgonomonas gadei were recombinantly produced in Escherichia coli and purified by chromatography. The enzymes have been identified as novel CE by sequence analysis and biochemical characterizations. The biochemical characterizations included the determination of the molecular weight, the substrate spectrum, and the kinetic parameters, as well as the pH and temperature profiles in buffer and food matrices. Both identified CE epimerize cellobiose and lactose into the C2 epimerization products glucosylmannose and epilactose, respectively. The epimerization activity for lactose was maximal at pH 8.0 or 7.5 and 40°C in defined buffer systems for the CE from C. lentocellum and the CE from D. gadei, respectively. In addition, biotransformations of the foodstuff milk ultrafiltrate containing lactose were demonstrated. The CE from D. gadei was produced in a stirred-tank reactor (12 L) and purified using an automatic system. Enzyme production and purification in this scale indicates that a future upscaling of CE production is possible. The bioconversions of lactose in milk ultrafiltrate were carried out either in a batch process or in a continuously operated enzyme membrane reactor (EMR) process. Both processes ran at an industrially relevant low temperature of 8°C to reduce undesirable microbial growth. The enzyme was reasonably active at the low process temperature because the CE originated from a mesophilic organism. An epilactose yield of 29.9% was achieved in the batch process within 28 h of operation time. In the continuous EMR process, the epilactose yield in the product stream was lower, at 18.5%. However, the enzyme productivity

Novel adsorptive ultrafiltration membranes derived from polyvinyltetrazole-co-polyacrylonitrile for Cu(II) ions removal

KAUST Repository

Kumar, Mahendra; Shevate, Rahul; Hilke, Roland; Peinemann, Klaus-Viktor

2016-01-01

Novel adsorptive ultrafiltration membranes were manufactured from synthesized polyvinyltetrazole−co−polyacrylonitrile (PVT−co−PAN) by nonsolvent induced phase separation (NIPS). PVT−co−PAN with various degree of functionalization (DF) was synthesized via a [3+2] cycloaddition reaction at 60°C using a commercial PAN. PVT−co−PAN with varied DF was then explored to prepare adsorptive membranes. The membranes were characterized by surface zeta potential and static water contact angle measurements, scanning electron microscopy as well as atomic force microscopy (AFM) techniques. It was shown that PVT segments contributed to alter the pore size, charge and hydrophilic behavior of the membranes. The membranes became more negatively charged and hydrophilic after addition of PVT segments. The PVT segments in the membranes served as the major binding sites for adsorption of Cu(II) ions from aqueous solution. The maximum adsorption of Cu(II) ions by the membranes in static condition and in a continuous ultrafiltration of 10 ppm solution was attained at pH = 5. The adsorption data suggest that the Freundlich isotherm model describes well Cu(II) ions adsorption on the membranes from aqueous solution. The adsorption capacity obtained from the Freundlich isotherm model was 44.3 mg g−1; this value is higher than other membrane adsorption data reported in the literature. Overall, the membranes fabricated from PVT−co−PAN are attractive for efficient removal of heavy metal ions under the optimized conditions.

Novel adsorptive ultrafiltration membranes derived from polyvinyltetrazole-co-polyacrylonitrile for Cu(II) ions removal

KAUST Repository

Kumar, Mahendra

2016-05-04

Novel adsorptive ultrafiltration membranes were manufactured from synthesized polyvinyltetrazole−co−polyacrylonitrile (PVT−co−PAN) by nonsolvent induced phase separation (NIPS). PVT−co−PAN with various degree of functionalization (DF) was synthesized via a [3+2] cycloaddition reaction at 60°C using a commercial PAN. PVT−co−PAN with varied DF was then explored to prepare adsorptive membranes. The membranes were characterized by surface zeta potential and static water contact angle measurements, scanning electron microscopy as well as atomic force microscopy (AFM) techniques. It was shown that PVT segments contributed to alter the pore size, charge and hydrophilic behavior of the membranes. The membranes became more negatively charged and hydrophilic after addition of PVT segments. The PVT segments in the membranes served as the major binding sites for adsorption of Cu(II) ions from aqueous solution. The maximum adsorption of Cu(II) ions by the membranes in static condition and in a continuous ultrafiltration of 10 ppm solution was attained at pH = 5. The adsorption data suggest that the Freundlich isotherm model describes well Cu(II) ions adsorption on the membranes from aqueous solution. The adsorption capacity obtained from the Freundlich isotherm model was 44.3 mg g−1; this value is higher than other membrane adsorption data reported in the literature. Overall, the membranes fabricated from PVT−co−PAN are attractive for efficient removal of heavy metal ions under the optimized conditions.

An innovative treatment concept for future drinking water production : Fluidized ion exchange – ultrafiltration – nanofiltration – granular activated carbon filtration

NARCIS (Netherlands)

Li, S.; Heijman, S.G.J.; Verberk, J.Q.J.C.; Van Dijk, J.C.

2009-01-01

A new treatment concept for drinking water production from surface water has been investigated on a pilot scale. The treatment concept consists of fluidized ion exchange (FIEX), ultrafiltration (UF), nanofiltration (NF), and granular activated carbon filtration (GAC). The FIEX process removed

A hybrid microbial fuel cell membrane bioreactor with a conductive ultrafiltration membrane biocathode for wastewater treatment

KAUST Repository

Malaeb, Lilian; Katuri, Krishna; Logan, Bruce E.; Maab, Husnul; Nunes, Suzana Pereira; Saikaly, Pascal

2013-01-01

A new hybrid, air-biocathode microbial fuel cell-membrane bioreactor (MFC-MBR) system was developed to achieve simultaneous wastewater treatment and ultrafiltration to produce water for direct reclamation. The combined advantages of this system were achieved by using an electrically conductive ultrafiltration membrane as both the cathode and the membrane for wastewater filtration. The MFC-MBR used an air-biocathode, and it was shown to have good performance relative to an otherwise identical cathode containing a platinum catalyst. With 0.1 mm prefiltered domestic wastewater as the feed, the maximum power density was 0.38 W/m2 (6.8 W/m3) with the biocathode, compared to 0.82 W/m2 (14.5 W/m3) using the platinum cathode. The permeate quality from the biocathode reactor was comparable to that of a conventional MBR, with removals of 97% of the soluble chemical oxygen demand, 97% NH3-N, and 91% of total bacteria (based on flow cytometry). The permeate turbidity was <0.1 nephelometric turbidity units. These results show that a biocathode MFC-MBR system can achieve high levels of wastewater treatment with a low energy input due to the lack of a need for wastewater aeration. © 2013 American Chemical Society.

A hybrid microbial fuel cell membrane bioreactor with a conductive ultrafiltration membrane biocathode for wastewater treatment

KAUST Repository

Malaeb, Lilian

2013-10-15

A new hybrid, air-biocathode microbial fuel cell-membrane bioreactor (MFC-MBR) system was developed to achieve simultaneous wastewater treatment and ultrafiltration to produce water for direct reclamation. The combined advantages of this system were achieved by using an electrically conductive ultrafiltration membrane as both the cathode and the membrane for wastewater filtration. The MFC-MBR used an air-biocathode, and it was shown to have good performance relative to an otherwise identical cathode containing a platinum catalyst. With 0.1 mm prefiltered domestic wastewater as the feed, the maximum power density was 0.38 W/m2 (6.8 W/m3) with the biocathode, compared to 0.82 W/m2 (14.5 W/m3) using the platinum cathode. The permeate quality from the biocathode reactor was comparable to that of a conventional MBR, with removals of 97% of the soluble chemical oxygen demand, 97% NH3-N, and 91% of total bacteria (based on flow cytometry). The permeate turbidity was <0.1 nephelometric turbidity units. These results show that a biocathode MFC-MBR system can achieve high levels of wastewater treatment with a low energy input due to the lack of a need for wastewater aeration. © 2013 American Chemical Society.

Study to determine the technical and economic feasibility of reclaiming chemicals used in micellar polymer and low tension surfactant flooding. Final report. [Ultrafiltration membranes and reverse osmosis membranes

Energy Technology Data Exchange (ETDEWEB)

Stephens, R.H.; Himmelblau, A.; Donnelly, R.G.

1978-02-01

Energy Resources Company has developed a technology for use with enhanced oil recovery to achieve emulsion breaking and surfactant recovery. By using ultrafiltration membranes, the Energy Resources Company process can dewater an oil-in-water type emulsion expected from enhanced oil recovery projects to the point where the emulsion can be inverted and treated using conventional emulsion-treating equipment. By using a tight ultrafiltration membrane or a reverse osmosis membrane, the Energy Resources Company process is capable of recovering chemicals such as surfactants used in micellar polymer flooding.

Selective removal of dissolved toxic metals from groundwater by ultrafiltration in combination with chemical treatment

International Nuclear Information System (INIS)

Buckley, L.P.; Le, V.T.; McConeghy, G.J.; Martin, J.F.

1989-09-01

An alternative in-place process for the removal of toxic heavy metals based on aqueous solution chemistry and treatment is being evaluated under the auspices of the Emerging Technologies Program funded through the USEPA's Superfund Innovative Technology Evaluation Program. The technique involves the contacting of aqueous solutions containing the heavy metal contaminants with low concentrations of polyelectrolytes, and then removing the polyelectrolytes from solution with ultrafiltration membranes. The first phase of the program is considered complete. Success has been achieved for the separation of soluble, heavy metal ions: cadmium, lead, and mercury even in the presence of an organic compound, toluene. Removal was successful at alkaline conditions, using any combination of membrane material or polyelectrolyte. Arsenic was removed, but not effectively, using the current polyelectrolytes, simply because arsenic is present as an anionic species rather than as a cationic species. Optimization of the process variables is nearing completion and pilot and field testing will take place in the second year of the program to verify the process under realistic conditions and to establish process economics

Testing Modified Gravity Theories via Wide Binaries and GAIA

Science.gov (United States)

Pittordis, Charalambos; Sutherland, Will

2018-06-01

The standard ΛCDM model based on General Relativity (GR) including cold dark matter (CDM) is very successful at fitting cosmological observations, but recent non-detections of candidate dark matter (DM) particles mean that various modified-gravity theories remain of significant interest. The latter generally involve modifications to GR below a critical acceleration scale ˜10-10 m s-2. Wide-binary (WB) star systems with separations ≳ 5 kAU provide an interesting test for modified gravity, due to being in or near the low-acceleration regime and presumably containing negligible DM. Here, we explore the prospects for new observations pending from the GAIA spacecraft to provide tests of GR against MOND or TeVes-like theories in a regime only partially explored to date. In particular, we find that a histogram of (3D) binary relative velocities, relative to equilibrium circular velocity predicted from the (2D) projected separation predicts a rather sharp feature in this distribution for standard gravity, with an 80th (90th) percentile value close to 1.025 (1.14) with rather weak dependence on the eccentricity distribution. However, MOND/TeVeS theories produce a shifted distribution, with a significant increase in these upper percentiles. In MOND-like theories without an external field effect, there are large shifts of order unity. With the external field effect included, the shifts are considerably reduced to ˜0.04 - 0.08, but are still potentially detectable statistically given reasonably large samples and good control of contaminants. In principle, followup of GAIA-selected wide binaries with ground-based radial velocities accurate to ≲ 0.03 { km s^{-1}} should be able to produce an interesting new constraint on modified-gravity theories.

Development of a Model for a Continuous Ultra-Filtration System

DEFF Research Database (Denmark)

Jhamb, Spardha Virendra; Gani, Rafiqul; Rype, Jens-Ulrik

Due to the wide applicability and simplicity of the ultra-filtration process, it is currently being used in a variety of commercial processes for the purpose of separation and concentration of valuable products and/or recovery of raw materials from dilute systems [1]. A predictive model......) system consisting of different geometry (and ‘N’ membrane stacks) used for the concentration of enzyme solutions from a known inlet concentration to a desired (target) outlet concentration during the recovery and/or downstream processing of enzymes. The envisaged purpose of this model is to improve...... for a system derived from first principles, is instrumental in evading the costs of conducting time-consuming experiments while also allowing one to not be dependent on a trial and error analysis approach. The validated final model can serve to understand the operational issues of the process and from...

Compaction comparison testing using a modified impact soil tester and nuclear density gauge

Energy Technology Data Exchange (ETDEWEB)

Erchul, R.A.

1999-07-01

The purpose of this paper is to compare test results of a modified Impact Soil Tester (IST) on compacted soil with data obtained from the same soil using a nuclear density gauge at the US Army Corp of Engineer's Buena Vista Flood Wall project in Buena Vista, Virginia. The tests were run during construction of the earth flood wall during the summer of 1996. This comparison testing demonstrated the credibility of the procedure developed for the IST as a compacting testing device. The comparison data was obtained on a variety of soils ranging from silty sands to clays. The Flood Wall comparison compaction data for 90% Standard Proctor shows that the results of the IST as modified are consistent with the nuclear density gauge 89% of the time for all types of soil tested. However, if the soils are more cohesive than the results are consistent with the nuclear density gauge 97% of the time. In addition these comparison tests are in general agreement with comparison compaction testing using the same testing techniques and methods of compacted backfill in utility trenches conducted earlier for the Public Works Department, Chesterfield County, Virginia.

Compaction comparison testing using a modified impact soil tester and nuclear density gauge

International Nuclear Information System (INIS)

Erchul, R.A.

1999-01-01

The purpose of this paper is to compare test results of a modified Impact Soil Tester (IST) on compacted soil with data obtained from the same soil using a nuclear density gauge at the US Army Corp of Engineer's Buena Vista Flood Wall project in Buena Vista, Virginia. The tests were run during construction of the earth flood wall during the summer of 1996. This comparison testing demonstrated the credibility of the procedure developed for the IST as a compacting testing device. The comparison data was obtained on a variety of soils ranging from silty sands to clays. The Flood Wall comparison compaction data for 90% Standard Proctor shows that the results of the IST as modified are consistent with the nuclear density gauge 89% of the time for all types of soil tested. However, if the soils are more cohesive than the results are consistent with the nuclear density gauge 97% of the time. In addition these comparison tests are in general agreement with comparison compaction testing using the same testing techniques and methods of compacted backfill in utility trenches conducted earlier for the Public Works Department, Chesterfield County, Virginia

Ultrafiltration and thermal processing effects on Maillard reaction products and biological properties of date palm sap syrups (Phoenix dactylifera L.).

Science.gov (United States)

Makhlouf-Gafsi, Ines; Krichen, Fatma; Mansour, Riadh Ben; Mokni, Abir; Sila, Assad; Bougatef, Ali; Blecker, Christophe; Attia, Hamadi; Besbes, Souhail

2018-08-01

The effect of ultrafiltration process and temperature concentration on MRPs content and antioxidant, antimicrobial and cytotoxic properties of date palm sap syrups were investigated. MRPs were analyzed by HPLC. Antioxidant activity was evaluated by reducing power and DPPH free radical and H 2 O 2 scavenging activities. Antimicrobial activity was evaluated by the agar disk diffusion method. In vitro cytotoxic activity was examined by cell proliferation assay. Date sap syrups displayed strong antioxidant activities which are correlated 5HMF and 2F contents. In addition, concentration at 100 °C, unlike ultrafiltration process, enhanced significantly the antioxidant activities sap syrups and total phenolic contents. The antimicrobial activities showed marked activity against S. enterica, P. aeruginosa, S. aureus, L. monocytogenes with an inhibition zone of 21, 34, 27 and 34 mm respectively. Cytotoxicity assays showed that sap syrups can inhibit the proliferation of HeLa cell lines at high concentration. Published by Elsevier Ltd.

Preparation and characterization of a novel highly hydrophilic and antifouling polysulfone/nanoporous TiO2 nanocomposite membrane

Science.gov (United States)

Cheraghi Bidsorkhi, H.; Riazi, H.; Emadzadeh, D.; Ghanbari, M.; Matsuura, T.; Lau, W. J.; Ismail, A. F.

2016-10-01

In this research, novel ultrafiltration nanocomposite membranes were prepared by incorporating self-synthesized nanoporous titanium dioxide (NTiO2) nanoparticles into polysulfone. The surface of the nanoparticle was treated with a silane-based modifier to improve its distribution in the host polymer. Atomic-force microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller, transmission electron microscopy, energy-dispersive x-ray spectroscopy, porosity and contact angle tests were conducted to characterize the properties of the particles as well as the fabricated nanocomposite membranes. The effects of the nanoparticle incorporation were evaluated by conducting ultrafiltration experiments. It was reported that the membrane pure water flux was increased with increasing NTiO2 loading owing to the high porosity of the nanoparticles embedded and/or formation of enlarged pores upon addition of them. The antifouling capacity of the membranes was also tested by ultrafiltration of bovine serum albumin fouling solution. It was found that both water flux and antifouling capacity tended to reach desired level if the NTiO2 added was at optimized loading.

TOPOLOGY OF A LARGE-SCALE STRUCTURE AS A TEST OF MODIFIED GRAVITY

International Nuclear Information System (INIS)

Wang Xin; Chen Xuelei; Park, Changbom

2012-01-01

The genus of the isodensity contours is a robust measure of the topology of a large-scale structure, and it is relatively insensitive to nonlinear gravitational evolution, galaxy bias, and redshift-space distortion. We show that the growth of density fluctuations is scale dependent even in the linear regime in some modified gravity theories, which opens a new possibility of testing the theories observationally. We propose to use the genus of the isodensity contours, an intrinsic measure of the topology of the large-scale structure, as a statistic to be used in such tests. In Einstein's general theory of relativity, density fluctuations grow at the same rate on all scales in the linear regime, and the genus per comoving volume is almost conserved as structures grow homologously, so we expect that the genus-smoothing-scale relation is basically time independent. However, in some modified gravity models where structures grow with different rates on different scales, the genus-smoothing-scale relation should change over time. This can be used to test the gravity models with large-scale structure observations. We study the cases of the f(R) theory, DGP braneworld theory as well as the parameterized post-Friedmann models. We also forecast how the modified gravity models can be constrained with optical/IR or redshifted 21 cm radio surveys in the near future.

Newton's second law versus modified-inertia MOND: A test using the high-latitude effect

International Nuclear Information System (INIS)

Ignatiev, A. Yu.

2008-01-01

The modified-inertia MOND is an approach that proposes a change in Newton's second law at small accelerations as an alternative to dark matter. Recently it was suggested that this approach can be tested in terrestrial laboratory experiments. One way of doing the test is based on the static high-latitude equinox modified-inertia effect: around each equinox date, 2 spots emerge on the Earth where static bodies experience spontaneous displacement due to the violation of Newton's second law required by the modified-inertia MOND. Here, a detailed theory of this effect is developed and estimates of the magnitude of the signal due to the effect are obtained. The expected displacement of a mirror in a gravitational-wave interferometer is found to be about 10 -14 m. Some experimental aspects of the proposal are discussed

Short-term adhesion and long-term biofouling testing of polydopamine and poly(ethylene glycol) surface modifications of membranes and feed spacers for biofouling control

KAUST Repository

Miller, Daniel J.

2012-08-01

Ultrafiltration, nanofiltration membranes and feed spacers were hydrophilized with polydopamine and polydopamine- g-poly(ethylene glycol) surface coatings. The fouling propensity of modified and unmodified membranes was evaluated by short-term batch protein and bacterial adhesion tests. The fouling propensity of modified and unmodified membranes and spacers was evaluated by continuous biofouling experiments in a membrane fouling simulator. The goals of the study were: 1) to determine the effectiveness of polydopamine and polydopamine- g-poly(ethylene glycol) membrane coatings for biofouling control and 2) to compare techniques commonly used in assessment of membrane biofouling propensity with biofouling experiments under practical conditions. Short-term adhesion tests were carried out under static, no-flow conditions for 1 h using bovine serum albumin, a common model globular protein, and Pseudomonas aeruginosa, a common model Gram-negative bacterium. Biofouling tests were performed in a membrane fouling simulator (MFS) for several days under flow conditions similar to those encountered in industrial modules with the autochthonous drinking water population and acetate dosage as organic substrate. Polydopamine- and polydopamine- g-poly(ethylene glycol)-modified membranes showed significantly reduced adhesion of bovine serum albumin and P. aeruginosa in the short-term adhesion tests, but no reduction of biofouling was observed during longer biofouling experiments with modified membranes and spacers. These results demonstrate that short-term batch adhesion experiments using model proteins or bacteria under static conditions are not indicative of biofouling, while continuous biofouling experiments showed that membrane surface modification by polydopamine and polydopamine- g-poly(ethylene glycol) is not effective for biofouling control. © 2012 Elsevier Ltd.

A validated inductively coupled plasma mass spectrometry (ICP-MS) method for the quantification of total platinum content in plasma, plasma ultrafiltrate, urine and peritoneal fluid.

Science.gov (United States)

Lemoine, Lieselotte; Thijssen, Elsy; Noben, Jean-Paul; Adriaensens, Peter; Carleer, Robert; Speeten, Kurt Van der

2018-04-15

Oxaliplatin is a platinum (Pt) 1 containing antineoplastic agent that is applied in current clinical practice for the treatment of colon and appendiceal neoplasms. A fully validated, highly sensitive, high throughput inductively coupled plasma mass spectrometry (ICP-MS) method is provided to quantify the total Pt content in plasma, plasma ultrafiltrate, urine and peritoneal fluid. In this ICP-MS approach, the only step of sample preparation is a 1000-fold dilution in 0.5% nitric acid, allowing the analysis of 17 samples per hour. Detection of Pt was achieved over a linear range of 0.01-100 ng/mL. The limit of quantification was 18.0 ng/mL Pt in plasma, 8.0 ng/mL in ultrafiltrate and 6.1 ng/mL in urine and peritoneal fluid. The ICP-MS method was further validated for inter-and intraday precision and accuracy (≤15%), recovery, robustness and stability. Short-term storage of the biofluids, for 14 days, can be performed at -4 °C, -24 °C and -80 °C. As to long-term stability, up to 5 months, storage at -80 °C is encouraged. Furthermore, a timeline assessing the total and unbound Pt fraction in plasma and ultrafiltrate over a period of 45 h is provided. Following an incubation period of 5 h at 37 °C, 19-21% of Pt was recovered in the ultrafiltrate, emphasizing the extensive and rapid binding of oxaliplatin-derived Pt to plasma proteins. The described method can easily be implemented in a routine setting for pharmacokinetic studies in patients treated with oxaliplatin-based hyperthermic intraperitoneal perioperative chemotherapy. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of white noise on Callsign Acquisition Test and Modified Rhyme Test scores.

Science.gov (United States)

Blue-Terry, Misty; Letowski, Tomasz

2011-02-01

The Callsign Acquisition Test (CAT) is a speech intelligibility test developed by the US Army Research Laboratory. The test has been used to evaluate speech transmission through various communication systems but has not been yet sufficiently standardised and validated. The aim of this study was to compare CAT and Modified Rhyme Test (MRT) performance in the presence of white noise across a range of signal-to-noise ratios (SNRs). A group of 16 normal-hearing listeners participated in the study. The speech items were presented at 65 dB(A) in the background of white noise at SNRs of -18, -15, -12, -9 and -6 dB. The results showed a strong positive association (75.14%) between the two tests, but significant differences between the CAT and MRT absolute scores in the range of investigated SNRs. Based on the data, a function to predict CAT scores based on existing MRT scores and vice versa was formulated. STATEMENT OF RELEVANCE: This work compares performance data of a common speech intelligibility test (MRT) with a new test (CAT) in the presence of white noise. The results here can be used as a part of the standardisation procedures and provide insights to the predictive capabilities of the CAT to quantify speech intelligibility communication in high-noise military environments.

A new modified wetting test and an alternative disintegration test for orally disintegrating tablets.

Science.gov (United States)

Hooper, Patrick; Lasher, Jason; Alexander, Kenneth S; Baki, Gabriella

2016-02-20

Industrial manufacturing of solid oral dosage forms require quality tests, such as friability, hardness, and disintegration. The United States Pharmacopeia (USP) disintegration test uses 900mL of water. However, recent studies of orally disintegrating tablets (ODTs) have shown that this volume does not accurately portray the oral environment. In our study, various tests were conducted with a more moderate amount of water that accurately resembles the oral environment. A simulated wetting test was performed to calculate the water absorption ratio. Results showed that wetting was comparable to disintegration. Although the wetting test worked for most types of ODTs, it had limitations that produced inaccurate results. This led to the use of a modified shaking water bath test. This test was found to work for all types of ODT products and was not subject to the limitations of the wetting test. The shake test could provide disintegration times rather than water permeation times; however, it could not be used to calculate the water absorption ratio. A strong correlation was observed between the standardized shake test and the USP disintegration times for the tablets. This shake test could be used during the development stages and quality tests for ODTs with relative ease. Copyright © 2015 Elsevier B.V. All rights reserved.

Fish protein hydrolysate production from sardine solid waste by crude pepsin enzymatic hydrolysis in a bioreactor coupled to an ultrafiltration unit

International Nuclear Information System (INIS)

Benhabiles, M.S.; Abdi, N.; Drouiche, N.; Lounici, H.; Pauss, A.; Goosen, M.F.A.; Mameri, N.

2012-01-01

The aims of the study were to optimize the production a fish protein hydrolysate (FPH) by enzymatic hydrolysis of sardine solid waste using crude pepsin, and to scale up the process in a bioreactor coupled to an ultrafiltration unit for product recovery. Results showed that the crude pepsin prepared by autolysis of the mucous membranes of a sheep stomach at optimal conditions (i. e. pH = 1.5–2 and incubation time of 6 h) could be satisfactory used for the enzymatic hydrolysis of fish solid waste. The optimal conditions for enzymatic reaction were: temperature 48 °C, and pH 1.5. The scale up of the enzymatic hydrolysis and the coupling of the reactor an ultrafiltration unit to concentrate the hydrolysate gave good results with a rejection coefficient for the protein hydrolysate product in the range of 90%. The volumetric concentration factor was 2.5, with a permeate flux of 200 L m −2 bar −1 . However, the results also suggest that the ultrafiltration product concentration process may be operating beyond the critical flux at which point irreversible membrane fouling occurs. - Highlights: ► Evaluating to produce a (FPH) by enzymatic hydrolysis of sardine solid wastes was achieved. ► Investigation of key parameters for optimal conditions for enzymatic hydrolysis have been studied. ► Valorization of sardine waste was realized by enzymatic hydrolysis process. ► Performances of this enzyme gave comparable results to those obtained with commercial pepsin. ► The nutritional quality of the FPH produced appears to be satisfactory.

Removal Natural Organic Matter (NOM in Peat Water from Wetland Area by Coagulation-Ultrafiltration Hybrid Process with Pretreatment Two-Stage Coagulation

Directory of Open Access Journals (Sweden)

Mahmud Mahmud

2016-06-01

Full Text Available The primary problem encountered in the application of membrane technology was membrane fouling. During this time, hybrid process by coagulation-ultrafiltration in drinking water treatment that has been conducted by some research, using by one-stage coagulation. The goal of this research was to investigate the effect of two-stage coagulation as a pretreatment towards performance of the coagulation-ultrafiltration hybrid process for removal NOM in the peat water. Coagulation process, either with the one-stage or two-stage coagulation was very good in removing charge hydrophilic fraction, i.e. more than 98%. NOM fractions of the peat water, from the most easily removed by the two-stage coagulation and one-stage coagulation process was charged hydrophilic>strongly hydrophobic>weakly hydrophobic>neutral hydrophilic. The two-stage coagulation process could removed UV254 and colors with a little better than the one-stage coagulation at the optimum coagulant dose. Neutral hydrophilic fraction of peat water NOM was the most influential fraction of UF membrane fouling. The two-stage coagulation process better in removing the neutral hidrophilic fraction, while removing of the charged hydrophilic, strongly hydrophobic and weakly hydrophobic similar to the one-stage coagulation. Hybrid process by pretreatment with two-stage coagulation, beside can increased removal efficiency of UV254 and color, also can reduced fouling rate of the ultrafiltration membraneIt must not exceed 250 words, contains a brief summary of the text, covering the whole manuscript without being too elaborate on every section. Avoid any abbreviation, unless it is a common knowledge or has been previously stated.

Removal Natural Organic Matter (NOM in Peat Water from Wetland Area by Coagulation-Ultrafiltration Hybrid Process with Pretreatment Two-Stage Coagulation

Directory of Open Access Journals (Sweden)

Mahmud Mahmud

2013-11-01

Full Text Available The primary problem encountered in the application of membrane technology was membrane fouling. During this time, hybrid process by coagulation-ultrafiltration in drinking water treatment that has been conducted by some research, using by one-stage coagulation. The goal of this research was to investigate the effect of two-stage coagulation as a pretreatment towards performance of the coagulation-ultrafiltration hybrid process for removal NOM in the peat water. Coagulation process, either with the one-stage or two-stage coagulation was very good in removing charge hydrophilic fraction, i.e. more than 98%. NOM fractions of the peat water, from the most easily removed by the two-stage coagulation and one-stage coagulation process was charged hydrophilic>strongly hydrophobic>weakly hydrophobic>neutral hydrophilic. The two-stage coagulation process could removed UV254 and colors with a little better than the one-stage coagulation at the optimum coagulant dose. Neutral hydrophilic fraction of peat water NOM was the most influential fraction of UF membrane fouling. The two-stage coagulation process better in removing the neutral hidrophilic fraction, while removing of the charged hydrophilic, strongly hydrophobic and weakly hydrophobic similar to the one-stage coagulation. Hybrid process by pretreatment with two-stage coagulation, beside can increased removal efficiency of UV254 and color, also can reduced fouling rate of the ultrafiltration membraneIt must not exceed 250 words, contains a brief summary of the text, covering the whole manuscript without being too elaborate on every section. Avoid any abbreviation, unless it is a common knowledge or has been previously stated.

Effects of Preparation Conditions on Morphology of Polyacrylonitrile Micro/Ultrafiltration Membrane and Its Application in Protein and Fat Separation from Milk

Directory of Open Access Journals (Sweden)

Seyed Ali Alavi

2014-04-01

Full Text Available Polyacrylonitrile (PAN micro/ultrafiltration membranes were prepared by phase inversion method. The effects of various preparation conditions including polymeric solution concentration, evaporation time, temperature, composition and residence time of the coagulation bath were investigated. Various important membrane characteristics such as pore size, bulk porosity, and mechanical and morphological properties were taken into the consideration. The characterizations were performed by measuring the bubble point, water flux, tensile strength and scanning electron microscopy (SEM analyses. The results showed that by increasing the polymeric solution concentration from 13 to 17 wt%, the porosity and water flux were decreased. Moreover, the membrane skin layer was considerably thickened with a very significant decrease in its pore sizes which was achieved in ultrafiltration region. By increasing the evaporation time at atmospheric pressure, membrane skin layer was thickened and the pore sizes were decreased. Low coagulation bath temperatures (below 30°C resulted in lower pore size, water flux, and an increase in membrane mechanical strength. Introduction of isopropanol (IPA into the water coagulation bath led to lower coagulation rate and consequently, the formation of smaller pores became possible by using pure isopropanol as coagulation bath. Furthermore, by increasing the residence time in coagulation bath, a more porous structure with more uniform pore sizes were formed that showed better mechanical properties. Finally, the so-called ultrafiltration membranes were applied in concentration process of protein and milk fat. A protein rejection more than 93% was attained while a complete removal of milk fat was achieved.

[Subchronic toxicity test of genetically modified rice with double antisense starch-branching enzyme gene].

Science.gov (United States)

Li, Min; Piao, Jianhua; Yang, Xiaoguang

2010-07-01

To observe the sub-chronic toxic effects of the genetically modified rice with double antisense SBE gene. Based on gender and weight, weanling Wistar rats were randomly sorted into five groups: non-genetically modified rice group (group A), genetically modified rice group (group B), half genetically modified rice group (group C), quarter genetically modified rice group (group D) and AIN-93G normal diet group (group E). Indicators were the followings: body weight, food consumption, blood routine, blood biochemical test, organ weight, bone density and pathological examination of organs. At the middle of the experiment, the percentage of monocyte of female group B was less than that of group E (P 0.05), and no notable abnormity in the pathological examination of main organs (P > 0.05). There were no enough evidence to confirm the sub-chronic toxicity of genetically modified rice on rats.

Development of High-Antifouling PPSU Ultrafiltration Membrane by Using Compound Additives: Preparation, Morphologies, and Filtration Resistant Properties

OpenAIRE

Jie Liu; Zhencheng Zhong; Rui Ma; Weichen Zhang; Jiding Li

2016-01-01

In this study, flat sheet asymmetric polyphenylsulfone (PPSU) ultrafiltration membranes with enhanced antifouling properties were prepared with a non-solvent induced phase separation (NIPS) method through compound additives containing a polymeric pore-forming agent, a small molecular non-solvent and a surfactant. The formation processes of the porous asymmetric membranes with different kinds of additives were studied in detail, and the microstructure controllable preparation of membrane was a...

Use of a two-step ultrafiltration procedure to concentrate viral hemorrhagic septicemia virus (VHSV) in seawater.

Science.gov (United States)

Kim, Soo-Jin; Kim, Jong-Oh; Kim, Wi-Sik; Oh, Myung-Joo

2015-11-01

Viral hemorrhagic septicemia virus (VHSV) has been reported to be stable in both fresh as well as seawater, suggesting that VHSV exists in natural aquatic environments and might have an effect on the wild and cultured fish. However, VHSV is below the detectable limits of laboratory tests in natural seawater. In this study, a two-step ultrafiltration (UF) procedure was used to concentration of VHSV in seawater, providing samples that were tested for infectivity by cell culture and the presence of VHSV by quantitative reverse transcriptase PCR (qRT-PCR) methods. Overall, VHSV was approximately concentrated 100-1000 times in 1, 5 and 10 L, seawater volumes respectively: from 2.81×10(6) to 6.53×10(7)/mL and 10(3.3) to 10(3.8)TCID50/mL prior to the UF procedure, to 3.78×10(8), 1.16 × 10(11), and 9.12 × 10(10)/mL after the procedure. This is the first report of concentrating VHSV using an UF method that was specifically designed for seawater samples. In addition, the two-step UF procedure appears to be compatible with viral cell culture and qRT-PCR methods. Copyright © 2015 Elsevier B.V. All rights reserved.

A Review of Ultrafiltration and Forward Osmosis:application and modification

Science.gov (United States)

Chao, Gong; Shuili, Yu; Yufei, Shangguan; Zhengyang, Gu; Wangzhen, Yang; Liumo, Ren

2018-03-01

As a new treatment, membrane filtration is playing a more prominent role in treating many kinds of wastewater. Among all the membrane technologies, ultrafiltration(UF) and forward osmosis(FO) technology has been widely utilized and developed in oil field and refinery produced water. However, the reports about the differences between the two kinds of membrane technology used in oily wastewater are not yet available. In this review, at first we introduce the advantages, shortcomings and applications of UF and FO membranes. Among these, we mainly illustrate the membrane fouling, which now is a big problem because it increases costs and decreases membrane life to limit the industrialization of the membrane, and the different modification methods of membranes are discussed to figure out how these ways can ease the membrane fouling. Next we make a comparison of the two membranes. Finally we illustrate the future research topics.

Investigations of torrefied biomass grindability using a modified Hardgrove test

Directory of Open Access Journals (Sweden)

Tymoszuk Mateusz

2017-01-01

Full Text Available This paper presents results of investigations of torrefied biomass grindability using a modified Hardgrove test. The following types of torrefied biomass were used during the testing: alder chips, palm kernel shells and willow chips. Tests were conducted in a standard Hardgrove test mill for 50 cm3 volumetric samples (the same volume as applied in [1]. Volumetric samples of raw biomass were also tested for comparison purposes. Two ranges of the sample particle size were applied during the investigations: 0.6-1.18 mm (as in [2] and 0.2-1.18 mm. As opposed to the standard Hardgrove test, the cumulative passing mass of the product was determined for a wider range of passing of standard sieves. The obtained results point to an increase in the grindability of torrefied fuels compared to raw biomass. They can be used to categorize torrefied biomass fuels due to their grindability, and as basic information in semi-technical scale studies on torrefied biomass comminution features.

Ultrafiltration of skimmed goat milk increases its nutritional value by concentrating nonfat solids such as proteins, Ca, P, Mg, and Zn.

Science.gov (United States)

Moreno-Montoro, Miriam; Olalla, Manuel; Giménez-Martínez, Rafael; Bergillos-Meca, Triana; Ruiz-López, María Dolores; Cabrera-Vique, Carmen; Artacho, Reyes; Navarro-Alarcón, Miguel

2015-11-01

Goat milk has been reported to possess good nutritional and health-promoting properties. Usually, it must be concentrated before fermented products can be obtained. The aim of this study was to compare physicochemical and nutritional variables among raw (RM), skimmed (SM), and ultrafiltration-concentrated skimmed (UFM) goat milk. The density, acidity, ash, protein, casein, whey protein, Ca, P, Mg, and Zn values were significantly higher in UFM than in RM or SM. Dry extract and fat levels were significantly higher in UFM than in SM, and Mg content was significantly higher in UFM than in RM. Ultrafiltration also increased the solubility of Ca and Mg, changing their distribution in the milk. The higher concentrations of minerals and proteins, especially caseins, increase the nutritional value of UFM, which may therefore be more appropriate for goat milk yogurt manufacturing in comparison to RM or SM. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effect of ultrafiltration process on physico-chemical, rheological, microstructure and thermal properties of syrups from male and female date palm saps.

Science.gov (United States)

Makhlouf-Gafsi, Ines; Baklouti, Samia; Mokni, Abir; Danthine, Sabine; Attia, Hamadi; Blecker, Christophe; Besbes, Souhail; Masmoudi, Manel

2016-07-15

This study investigates the effect of the ultrafiltration process on physicochemical, rheological, microstructure and thermal properties of syrups from male and female date palm sap. All the studied syrups switched from pseudoplastic rheological behaviour (n=0.783) to Newtonian behaviour (n∼1) from 10 to 50 °C respectively and present similar thermal profiles. Results revealed that the ultrafiltration process significantly affects the rheological behaviour of the male and female syrups. These differences on rheological properties are attributed to the variation of chemical composition between sap and sap permeate syrups. Furthermore, the effect of temperature on viscosity of the syrups was investigated during heating and cooling processes at the same shear rate (50s(-1)). This study provides idea of the stability of the syrup by evaluating the area between heating and cooling curves. Actually, the syrup prepared from male sap permeate is the most stable between the four studied syrups. Copyright © 2016 Elsevier Ltd. All rights reserved.

Identification of Eupatilin from Artemisia argyi as a Selective PPARα Agonist Using Affinity Selection Ultrafiltration LC-MS

Directory of Open Access Journals (Sweden)

Yongsoo Choi

2015-07-01

Full Text Available Peroxisome proliferator-activated receptors (PPARs are key nuclear receptors and therapeutic targets for the treatment of metabolic diseases through the regulation of insulin resistance, diabetes, and dyslipidemia. Although a few drugs that target PPARs have been approved, more diverse and novel PPAR ligands are necessary to improve the safety and efficacy of available drugs. To expedite the search for new natural agonists of PPARs, we developed a screening assay based on ultrafiltration liquid chromatography-mass spectrometry (LC-MS that is compatible with complex samples such as dietary foods or botanical extracts. The known PPARα and/or PPARγ ligands resveratrol and rosiglitazone were used as positive controls to validate the developed method. When applied to the screening of an Artemisia argyi extract, eupatilin was identified as a selective PPARα ligand. A PPAR competitive binding assay based on FRET detection also confirmed eupatilin as a selective PPARα agonist exhibiting a binding affinity of 1.18 μM (IC50. Furthermore, eupatilin activation of the transcriptional activity of PPARα was confirmed using a cell-based transactivation assay. Thus, ultrafiltration LC-MS is a suitable assay for the identification of PPAR ligands in complex matrixes such as extracts of dietary foods and botanicals.

Current advances in screening for bioactive components from medicinal plants by affinity ultrafiltration mass spectrometry.

Science.gov (United States)

Chen, Guilin; Huang, Bill X; Guo, Mingquan

2018-05-21

Medicinal plants have played an important role in maintaining human health for thousands of years. However, the interactions between the active components in medicinal plants and some certain biological targets during a disease are still unclear in most cases. To conduct the high-throughput screening for small active molecules that can interact with biological targets, which is of great theoretical significance and practical value. The ultrafiltration mass spectrometry (UF-LC/MS) is a powerful bio-analytical method by combining affinity ultrafiltration and liquid chromatography-mass spectrometry (LC/MS), which could rapidly screen and identify small active molecules that bind to biological targets of interest at the same time. Compared with other analytical methods, affinity UF-LC/MS has the characteristics of fast, sensitive and high throughput, and is especially suitable for the complicated extracts of medicinal plants. In this review, the basic principle, characteristics and some most recent challenges in UF-LC/MS have been demonstrated. Meanwhile, the progress and applications of affinity UF-LC/MS in the discovery of the active components from natural medicinal plants and the interactions between small molecules and biological target proteins are also briefly summarised. In addition, the future directions for UF-LC/MS are also prospected. Affinity UF-LC/MS is a powerful tool in studies on the interactions between small active molecules and biological protein targets, especially in the high-throughput screening of active components from the natural medicinal plants. Copyright © 2018 John Wiley & Sons, Ltd.

Use of the modified Ames test as an indicator of the carcinogenicity of residual aromatic extracts

Energy Technology Data Exchange (ETDEWEB)

Boogaard, P.; Hedelin, A.; Riley, A.; Rushton, E.; Vaissiere, M.; Minsavage, G.; Rohde, A.; Dalbey, W.

2013-01-15

Existing data demonstrate that residual aromatic extracts (RAEs) can be either carcinogenic or non-carcinogenic. CONCAWE had previously concluded that 'Although limited data available indicate that some RAEs are weakly carcinogenic, it is not possible to provide a general recommendation. Classify on a case-by-case basis' (CONCAWE 2005). Therefore CONCAWE's Health/Toxicology Subgroup (H/TSG) has developed a proposal for the use of the modified Ames test as a short-term predictive screening tool for decisions on the classification of RAEs for carcinogenicity. The relationship between RAE chemistry and carcinogenic potential is not as well understood as it is for some other categories of substances, e.g. Other Lubricant Base Oils (OLBO). However, a correlation has been found between the results of the skin carcinogenicity bioassay and the mutagenicity index (MI) obtained from the modified Ames test. Data supporting this correlation are summarised in this report. The H/TSG confirmed that the modified Ames test can be used as a predictive screening tool and that a cut-off value can be established to make a distinction between carcinogenic and non-carcinogenic products. RAEs with a MI > 0.4 demonstrated carcinogenic potential upon dermal application to mouse skin with chronic exposure. RAEs with a MI > 0.4 did not demonstrate a carcinogenic potential. To justify the use of the modified Ames test with RAEs, additional analysis of the repeatability of the test with RAEs was required. With this objective, CONCAWE sponsored a round robin study with different samples of RAEs from member companies, at three different laboratories. The repeatability demonstrated in the round robin study with RAEs support the proposed use of the modified Ames test. As part of the tools available for use by member companies, the H/TSG proposed a standard operating procedure (SOP) (included as an Appendix to this report) on the conduct of the modified Ames test with RAEs. The H

Development of multifunctional nano/ultrafiltration membrane based on a chitosan thin film on alginate electrospun nanofibres

CSIR Research Space (South Africa)

Mokhena, Teboho C

2017-07-01

Full Text Available of Chemistry, University of the Free State (Qwaqwa Campus), Phuthaditjhaba, South Africa 3 Center for Advanced Materials, Qatar University, Doha, Qatar Abstract The aim of this study was to develop a high flux three-tier composite membrane composed of a... of multifunctional nano/ultrafiltration membrane based on a chitosan thin film on alginate electrospun nanofibres T.C. Mokhena1,2, A.S. Luyt3* 1 CSIR Materials Science and Manufacturing, Polymers and Composites, Port Elizabeth, South Africa. 2 Department...

Characterization of Irreversible Fouling after Ultrafiltration of Thermomechanical Pulp Mill Process Water

DEFF Research Database (Denmark)

Thuvander, Johan; Zarebska, Agata; Hélix-Nielsen, Claus

2018-01-01

process streams is fouling of the membranes. Fouling not only increases operating costs but also reduces the operating time of the membrane plant. When optimizing the membrane cleaning method, it is important to know which compounds cause the fouling. In this work fouling of an ultrafiltration membrane...... was studied. The fouling propensity of untreated process water and microfiltrated process water was compared. Fouled membranes were analyzed using scanning electron microscopy and attenuated total reflection Fourier transform infrared spectrometry. Acid hydrolysis of membranes exposed to untreated process......Large volumes of wastewater with dissolved wood components are treated in wastewater treatment plants at thermomechanical pulp mills. It has been shown previously that hemicelluloses in these wastewater streams can be recovered by membrane filtration. A serious obstacle when treating lignocellulose...

Fish protein hydrolysate production from sardine solid waste by crude pepsin enzymatic hydrolysis in a bioreactor coupled to an ultrafiltration unit

Energy Technology Data Exchange (ETDEWEB)

Benhabiles, M.S.; Abdi, N. [National Polytechnic school of Algiers, B.P. 182-16200, El Harrach, Algiers (Algeria); Drouiche, N., E-mail: nadjibdrouiche@yahoo.fr [National Polytechnic school of Algiers, B.P. 182-16200, El Harrach, Algiers (Algeria); Silicon Technology Development Unit (UDTS) 2, Bd Frantz Fanon BP140, Alger-7 Merveilles, 16000 (Algeria); Lounici, H. [National Polytechnic school of Algiers, B.P. 182-16200, El Harrach, Algiers (Algeria); Pauss, A. [University of Technology of Compiegne, Departement Genie chimique,B.P. 20.509, 60205 Compiegne cedex (France); Goosen, M.F.A. [Alfaisal University, Riyadh (Saudi Arabia); Mameri, N. [University of Technology of Compiegne, Departement Genie chimique,B.P. 20.509, 60205 Compiegne cedex (France)

2012-05-01

The aims of the study were to optimize the production a fish protein hydrolysate (FPH) by enzymatic hydrolysis of sardine solid waste using crude pepsin, and to scale up the process in a bioreactor coupled to an ultrafiltration unit for product recovery. Results showed that the crude pepsin prepared by autolysis of the mucous membranes of a sheep stomach at optimal conditions (i. e. pH = 1.5-2 and incubation time of 6 h) could be satisfactory used for the enzymatic hydrolysis of fish solid waste. The optimal conditions for enzymatic reaction were: temperature 48 Degree-Sign C, and pH 1.5. The scale up of the enzymatic hydrolysis and the coupling of the reactor an ultrafiltration unit to concentrate the hydrolysate gave good results with a rejection coefficient for the protein hydrolysate product in the range of 90%. The volumetric concentration factor was 2.5, with a permeate flux of 200 L m{sup -2} bar{sup -1}. However, the results also suggest that the ultrafiltration product concentration process may be operating beyond the critical flux at which point irreversible membrane fouling occurs. - Highlights: Black-Right-Pointing-Pointer Evaluating to produce a (FPH) by enzymatic hydrolysis of sardine solid wastes was achieved. Black-Right-Pointing-Pointer Investigation of key parameters for optimal conditions for enzymatic hydrolysis have been studied. Black-Right-Pointing-Pointer Valorization of sardine waste was realized by enzymatic hydrolysis process. Black-Right-Pointing-Pointer Performances of this enzyme gave comparable results to those obtained with commercial pepsin. Black-Right-Pointing-Pointer The nutritional quality of the FPH produced appears to be satisfactory.

Rapid Screening and Characterization of Acetylcholinesterase Inhibitors from Yinhuang Oral Liquid Using Ultrafiltration-liquid Chromatography-electrospray Ionization Tandem Mass Spectrometry.

Science.gov (United States)

Zhang, Haomin; Guo, Yinan; Meng, Lingwen; Sun, Hui; Yang, Yinping; Gao, Ying; Sun, Jiaming

2018-01-01

At present, approximately 17-25 million people in the world suffer from Alzheimer's disease (AD). The most efficacious and acceptable therapeutic drug clinically are the acetylcholinesterase inhibitors (AChEIs). Yinhuang oral liquid is a Chinese medicine preparation which contains AChEIs according to the literatures. However, no strategy has been presented for rapid screening and identification of AChEIs from Yinhuang oral liquid. To develop a method for rapid screening and identification of AChEIs from Yinhuang oral liquid using ultrafiltration-liquid chromatography-electrospray ionization tandem mass spectrometry (UF-LC-ESI-MS/MS). In this study, UF incubation conditions such as enzyme concentration, incubation time, and incubation temperature were optimized so as to get better screening results. The AChEIs from Yinhuang oral liquid were identified by high-performance liquid chromatography-ESI-MS and the improved Ellman method was used for the AChE inhibitory activity test in vitro . The results showed that Yinhuang oral liquid can inhibit the activity of AChE. We screened and identified seven compounds with potential AChE inhibitory activity from Yinhuang oral liquid, which provided experimental basis for the treatment and prevention of AD. The current technique was used to directly screen the active ingredients with acetylcholinesterase inhibition from complex traditional Chinese medicine, which was simple, rapid, accurate, and suitable for high-throughput screening of AChEI from complex systems. A UF-LC-ESI-MS/MS method for rapid screening and identification of AChEIs from Yinhuang oral liquid was developedSeven compounds were screened and identified with potential AChE inhibitory activity from Yinhuang oral liquidIt provided experimental basis of Yinhuang oral liquid for the treating and preventing AD. Abbreviations used: (AD): Alzheimer's disease; (UF-LC-ESI-MS/MS): ultrafiltration-liquid chromatography-electrospray ionization tandem mass spectrometry; (ACh

Prediction of power consumption and performance in ultrafiltration of simulated latex effluent using non-uniform pore sized membranes

Energy Technology Data Exchange (ETDEWEB)

Abdelrasoul, Amira; Doan, Huu; Lohi, Ali; Cheng, Chil-Hung [Ryerson University, 350 Victoria Street, Toronto (Canada)

2016-03-15

Tha aim of the present study was to develop a series of numerical models for an accurate prediction of the power consumption in ultrafiltration of simulated latex effluent. The developed power consumption model incorporated fouling attachment, as well as chemical and physical factors in membrane fouling, in order to ensure accurate prediction and scale-up. This model was applied to heterogeneous membranes with non-uniform pore sizes at a given operating conditions and membrane surface charges. Polysulfone flat membrane, with a membrane molecular weight cutoff (MWCO) of 60,000 dalton, at different surface charges was used under a constant flow rate and cross-flow mode. In addition, the developed models were examined using various membranes at a variety of surface charges so as to test the overall reliability and accuracy of these models. The power consumption predicted by the models corresponded to the calculated values from the experimental data for various hydrophilic and hydrophobic membranes with an error margin of 6.0% up to 19.1%.

A modified split Hopkinson pressure bar for toughness tests

Science.gov (United States)

Granier, N.; Grunenwald, T.

2006-08-01

In order to characterize material toughness or to study crack arrest under dynamic loading conditions, a new testing device has been developed at CEA/Valduc. A new Split Hopkinson Pressure Bar (SHPB) has been modified: it is now composed of a single incident bar and a double transmitter bar. With this facility, a notched specimen can be loaded under three points bending conditions. Qualification tests with titanium and steel notched samples are presented. Data treatment software has been adapted to estimate the sample deflection as a function of time and treat the energy balance. These results are compared with classical Charpy experiments. Effect of various contact areas between specimen and bars are studied to point out their influence on obtained measurements. The advantage of a “knife” contact compared to a plane one is then clearly demonstrated. All results obtained with this new testing device are in good agreement and show a reduced scattering.

Polyethersulfone/Graphene Oxide Ultrafiltration Membranes from Solutions in Ionic Liquid

KAUST Repository

Mahalingam, Dinesh. K.; Kim, DooLi.; Nunes, Suzana. P.

2017-01-01

Novel high flux polyethersulfone (PES) ultrafiltration membranes were fabricated by incorporating different amounts of graphene oxide (GO) sheets to PES as nanofillers. The membranes were prepared from solutions in 50/50 1-ethyl-3-methylimidazolium-diethylphosphate/N,N-dimethyl formamide. It was observed that the water permeance increased from 550 to 800 L m-2h-1bar-1, with incorporation of 1 wt% GO, keeping a molecular weight cut-off (MWCO) of approximately 32-34 kg mol-1. Cross-sectional scanning electron microscopy images of GO/PES membranes showed the formation of ultrathin selective layer unlike pristine membranes. Contact angle measurements confirmed the increase of hydrophilicity, by increasing the GO concentration. The rejection of humic acid and bovine serum albumin was demonstrated. The mechanical properties were improved, compared with the pristine membranes. The performance was just above the trade-off relationship between permeance and separation factor for PES membranes reported in the literature.

Polyethersulfone/Graphene Oxide Ultrafiltration Membranes from Solutions in Ionic Liquid

KAUST Repository

Mahalingam, Dinesh. K.

2017-07-18

Novel high flux polyethersulfone (PES) ultrafiltration membranes were fabricated by incorporating different amounts of graphene oxide (GO) sheets to PES as nanofillers. The membranes were prepared from solutions in 50/50 1-ethyl-3-methylimidazolium-diethylphosphate/N,N-dimethyl formamide. It was observed that the water permeance increased from 550 to 800 L m-2h-1bar-1, with incorporation of 1 wt% GO, keeping a molecular weight cut-off (MWCO) of approximately 32-34 kg mol-1. Cross-sectional scanning electron microscopy images of GO/PES membranes showed the formation of ultrathin selective layer unlike pristine membranes. Contact angle measurements confirmed the increase of hydrophilicity, by increasing the GO concentration. The rejection of humic acid and bovine serum albumin was demonstrated. The mechanical properties were improved, compared with the pristine membranes. The performance was just above the trade-off relationship between permeance and separation factor for PES membranes reported in the literature.

Relation between modified EPR test and suseptibility to IGSCC for sensitized alloy 600 in sulfur containing environments

International Nuclear Information System (INIS)

Ahn, M.Y.; Kwon, H.S.; Lee, J.H.

1993-01-01

A double loop (DL)-EPR (electrochemical potentiokinetic reactivation) test has been applied for evaluating the degree of sensitization for Alloy 600 aged for 1 to 100 hours at 700 degrees C, and modified to discrimiNate between varying degrees of chromium depletion while removing the problems of pitting and general corrosion. The modified DL-EPR testing conditions are obtained in 0.01M H 2 SO 4 + 10 ppm KSCN, 25 degrees C and at a scan rate of 0.5 mV/s. The results of the modified DL-EPR test are compared with those of the standard one and also correlated with the IGSCC susceptibility. IGSCC occurred in samples aged for shorter than 20 hours when tested in deaerated 0.05M Na 2 S 4 O 6 at a constant strain rate of 0.93 x 10 -6 /s. The susceptibility to IGSCC increases with decreasing aging time up to 1 hour, and is associated with the chromium depleted profile across the grain boundary; the deeper and narrower chromium depleted zone produces higher susceptibility to IGSCC. Except for the case for sample (700 degrees C/1 hour), there exists a good correlation between the results of the modified EPR test and the IGSCC susceptibility

Effect of Diafiltration on Preparation of Fermented Mung Beans Concentrate as Probiotic Savory Flavor Through Ultrafiltration Membrane

Directory of Open Access Journals (Sweden)

Aspiyanto Aspiyanto

2011-05-01

Full Text Available Diafiltration by means of the ultrafiltration system of probiotic fermented Mung beans (Phaseolus radiatus L. concentrate has been performed to reduce or eliminate salts and smaller impurities than the nominal cut-off of the membrane of 20,000 nominal weight cut-off (NWCO. These processes have been conducted as an attempt in order to get a probiotic product with organoleptic acceptability, composition, and the optimal total lactic acid bacteria (LAB counts because the presence of salts will affect on the viability of LAB and the cell lysis of LAB and limit its utility in food products. Concentrate of probiotic mung beans was prepared through fermentation of LAB using inoculum of LAB consisting of Lactobacillus bulgaricus and Streptococcus thermophylus (1 : 1 on fermented mung beans extract inoculated by inoculum of Rhizopus–C1 in rice substrates at salt condition. Ultrafiltration and diafiltration modes have been carried out at flow rate of 8.77 Liter/minute, room temperature and the pressure of 5 bar (0 to 79.7 minutes and 7 bar (0-154.5 minutes with the ratio of the volume of pure water to the volume of initial feed (number of diavolume, Nd of 0, 0.25, 0.5, 0.75, 1.0 and 1.25, respectively. The experiment results based on total LAB counts as a probiotic product show that a high Nd can reduce the salt content but increase the total LAB counts. Nd of 1.0 results reduce the salt content which is equal to retentate, permeate, and the optimal total LAB counts. Ultrafiltration and diafiltration modes at the pressure of 7 bar and Nd of 1.0 give a retentate with total solid of 6.1355%, salt of 1.3515% and remove 86.15% of the salt from probiotic fermented mung beans concentrate and total LAB counts of 10.73 log cycles. Meanwhile, the permeate obtained at this condition results in flux value of 10.83 Liter/m2.hour with contents of total solid of 6.8199%, salt of 1.325% and total LAB counts of 5.49 log cycles.

Study on the interaction of plasma protein binding rate between edaravone and taurine in human plasma based on HPLC analysis coupled with ultrafiltration technique.

Science.gov (United States)

Tang, Dao-quan; Li, Yin-jie; Li, Zheng; Bian, Ting-ting; Chen, Kai; Zheng, Xiao-xiao; Yu, Yan-yan; Jiang, Shui-shi

2015-08-01

In this work, two high-performance liquid chromatography (HPLC) assays were developed and validated for the independent determination of edaravone and taurine using 3-methyl-1-p-tolyl-5-pyrazolone and L-glutamine as internal standards. In in vitro experiments, human plasma was separately spiked with a mixture of edaravone and taurine, edaravone or taurine alone. Plasma was precipitated with acetonitrile containing 0.1% formic acid. Ultrafiltration was employed to obtain the unbound ingredients of the two drugs. The factors that might influence the ultrafiltration effiency were elaborately optimized. Plasma supernatant and ultrafiltrate containing taurine were derivated with o-phthalaldehyde and ethanethiol in the presence of 40 mmol/L sodium borate buffer (pH 10.2) at room temperature within 1 min. Chromatographic separations were achieved on an InertSustain C18 column (250 × 4.6 mm, 5 µm). Isocratic 50 mmol/L ammonium acetate-acetonitrile and gradient 50 mmol/L sodium acetate (pH 5.3)-methanol were respectively selected as the mobile phase for the determination of edaravone and taurine. All of the validation data including linearity, extraction recovery, precision, accuracy and stability conformed to the requirements. Results showed that there were no significant alterations in the plasma protein binding rate of taurine and edaravone, implying that the proposed combination therapy was pharmacologically feasible. Copyright © 2014 John Wiley & Sons, Ltd.

VALIDITY OF THE MODIFIED CONCONI TEST FOR DETERMINING VENTILATORY THRESHOLD DURING ON-WATER ROWING

Directory of Open Access Journals (Sweden)

Jorge Villamil Cabo

2011-12-01

Full Text Available The objectives of this study were to design a field test based on the Conconi protocol to determine the ventilatory threshold of rowers and to test its reliability and validity. A group of sixteen oarsmen completed a modified Conconi test for on-water rowing. The reliability of the detection of the heart rate threshold was evaluated using heart rate breaking point in the Conconi test and retest. Heart rate threshold was detected in 88.8% of cases in the test-retest. The validity of the modified Conconi test was evaluated by comparing the heart rate threshold data acquired with that obtained in a ventilatory threshold test (VT2. No significant differences were found for the values of different intensity parameters i.e. heart rate (HR, oxygen consumption (VO2, stroke rate (SR and speed (S between the heart rate threshold and the ventilatory threshold, (170.9 ± 6.8 vs. 169.3 ± 6.4 beats·min-1; 42.0 ± 8.6 vs. 43.5 ± 8.3 ml·kg-1·min-1; 25.8 ± 3.3 vs. 27.0 ± 3.2 strokes·min-1 and 14.4 ± 0.8 vs. 14.6 ± 0.8 km·h-1. The differences in averages obtained in the Conconi test-retest were small with a low standard error of the mean. The reliability data between the Conconi test-retest showed low coefficients of variations (CV and high intraclass correlation coefficients (ICC. The total errors for the Conconi test-retest are low for the measured variables (1.31 HR, 0.87 VO2, 0.65 SR, and 0.1 S. The Bland- Altman's method for analysis validity showed a strong concordance according to the analyzed variables. We conclude that the modified Conconi test for on-water rowing is a valid and reliable method for the determination of the second ventilatory threshold (VT2.

Use of ultra-filtration in organic-rich groundwater for the physical separation of thorium

International Nuclear Information System (INIS)

Singhal, R.K.; Basu, H.; Pimple, M.V.; Manisha, V.; Bassan, M.K.T.; Reddy, A.V.R.

2014-01-01

During this work, size fractionation technique 'ultra filtration' is used in physical speciation of thorium in organic rich groundwater. Laboratory simulated experiments were carried out to study the physical speciation of thorium in aquatic environment having elevated level of dissolved humus material classified as dissolved organic carbon (DOC). Samples were collected from organic rich environment having DOC in the range of 50-60 μg mL -1 . Th(IV) ions are extremely particle reactive having K d value of the order of 105-6, hence to avoid adsorption on suspended particulate matter, spiking of the solution with Th(NO 3 )4 was carried out in ground water samples after filtering through 450 nm pore size using suction filtration. Particles in dissolved state (colloids) ranging between 220 nm were separated using suction filtration assembly having a membrane with a pore diameter of 220 nm. Thereafter, solution was sequentially passed through the ultra-filtration membranes having pore diameters of 14 nm [300 k NMWL (nominal molecular weight limit)], 3.1 nm (50 k NMWL), 2.2 nm (30 k NMWL), 1.6 nm (10 k NMWL) and 1.1 nm (0.5 k NMWL) by using 'Stirred Ultra-filtration Cells', operating in concentration mode. Thorium has only one stable oxidation state i.e. IV, under all redox conditions in natural waters and therefore, its speciation is dominated by its interaction with various fractions of DOC. Experimental results show 50-60 % of the spiked Th is in association with fraction enriched with particles of 10 k NMWL (1.6 nm) followed by fraction enriched with particle of 0.5 k NMWL and <220 nm. (author)

Optimization of tensile method and specimen geometry in modified ring tensile test

International Nuclear Information System (INIS)

Kitano, Koji; Fuketa, Toyoshi; Sasajima, Hideo; Uetsuka, Hiroshi

2001-03-01

Several techniques in ring tensile test are proposed in order to evaluate mechanical properties of cladding under hoop loading condition caused by pellet/cladding mechanical interaction (PCMI). In the modified techniques, variety of tensile methods and specimen geometry are being proposed in order to limit deformation within the gauge section. However, the tensile method and the specimen geometry were not determined in the modified techniques. In the present study, we have investigated the tensile method and the specimen geometry through finite element method (FEM) analysis of specimen deformation and tensile test on specimens with various gauge section geometries. In using two-piece tensile tooling, the mechanical properties under hoop loading condition can be correctly evaluated when deformation part (gauge section) is put on the top of a half-mandrel, and friction between the specimen and the half-mandrel is reduced with Teflon tape. In addition, we have shown the optimum specimen geometry for PWR 17 by 17 type cladding. (author)

Test procedure for the Master-Lee and the modified Champion four inch hydraulic cutters

International Nuclear Information System (INIS)

Crystal, J.B.

1995-01-01

The Master-Lee and the modified Champion 4 Inch hydraulic cutters are being retested to gather and document information related to the following: determine if the Master-Lee cutters will cut the trunnions of an Aluminum fuel canister and a Stainless Steel fuel canister; determine if the Master-Lee cutters will cut 1 1/2 inch diameter fire hose; determine if the modified Champion 4 inch blade will cut sections of piping; and determine the effectiveness of the centering device for the Champion 4 Inch cutters. Determining the limitations of the hydraulic cutter will aid in the process of debris removal in the K-Basin. Based on a previous test, the cutters were returned to the manufacturer for modifications. The modifications to the Champion 4 Inch Cutter and further testing of the Master-Lee Cutter are the subjects of these feature tests

Size enlargement of radioactive and hazardous species and their separation by microfiltration and ultrafiltration membranes

International Nuclear Information System (INIS)

Vijayan, S.; Wong, C.F.; Buckley, L.P.

1993-01-01

Separation and volume reduction of aqueous solutions involving membranes is evolving into an expanding and diversified field. Numerous commercially successful membranes and their applications are now available. Among different driving forces used in membrane separation, pressure-driven separation has gained wide application. Depending on the size of the dissolved species in solution to be separated, the pressure needed to achieve the desired separation varies. The microfiltration and ultrafiltration membrane systems are low-pressure processes that generally operate below 350 kPa. To exploit these membranes in applications involving the removal of dissolved contaminants from solutions, it is essential to create a suitable size for the dissolved contaminants, so that the membranes can effectively retain them while producing a filtrate stream essentially free of contaminants. Size enlargement of the dissolved contaminants can be achieved through solution conditioning with the addition of one or a combination of chemical reagents and powdered materials. Examples of typical additives include: pH chemicals, polyelectrolytes, microorganisms and powdered adsorption/ion-exchange materials. In many situations, adequate control and optimization of the system chemistry and hydraulic conditions provide high selectivity and efficiency for contaminant removal. This paper summarizes removal efficiency data for cadmium, lead, mercury, uranium, arsenic, strontium-90/85, cesium-137 and iron. These data resulted from various initiatives on membrane technology undertaken during the past five years by the Waste Processing Technology group at Chalk River Laboratories. The technology involves size enlargement of contaminants present in waste solution, and their separation using either microfiltration or ultrafiltration. The data support remedial applications involving treatment of contaminated groundwater and soils

[Effect of priming solution and ultrafiltration on post-operative bleeding and blood transfusion in cardiac surgery. Randomized controlled trial].

Science.gov (United States)

Olmos Rodríguez, M; Ballester Hernández, J A; Arteta Bárcenas, M T; Rodríguez Cerezo, A; Vidarte Ortiz de Artiñano, M A; Veiga Alameda, C

2015-02-01

Assess the effectiveness of priming the extracorporeal circulation system with albumin-mannitol combined with ultrafiltration during extracorporeal circulation to reduce post-operative bleeding and transfusion requirements in heart surgery, as well as its impact on the fluid balance, coagulation and hematocrit parameters, re-operation for bleeding, ICU, and hospital length of stay. A total of 134 patients scheduled for heart surgery were randomized to receive Ringer's lactate 1,500mL in the priming reservoir (group C), or mannitol 20% 250mL, albumin 20% 150mL and Ringer's lactate 1,100mL combined with ultrafiltration (group T). Bleeding volume, transfusions, fluid balance, coagulation, and hematology parameters were determined until 48h in the post-operative period. There was a reduction of postoperative bleeding in group T, 1,165±789mL vs 992±662mL (P=.17), and red blood cell concentrate transfusions, 694±843mL vs 413±605mL (P=.03). Intra-operative and post-operative fluid balance was significantly less positive in group T, with an overall balance of 2,292±2,152mL vs 5,388±2,834mL (P<.001). There were higher values of hemoglobin and hematocrit, intraoperative (P<.001), on admission to ICU (P=.001), and at 6h (P=.05) in group T, and lower INR at 6h (P=.01) and 24h (P=.02). Re-operation rate and length of stay in ICU were higher in group C, but not statiscally significant. The priming of extracorporeal reservoir with mannitol, albumin, and Ringer's lactate, combined with ultrafiltration, significantly improves intra- and post-operative fluid balance, resulting in a reduction in blood transfusions, with no significant decrease in post-operative bleeding, re-operation bleeding rate, and length of stay in the ICU. Copyright © 2014 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

Water-soluble metal-binding polymers with ultrafiltration: A technology for the removal, concentration, and recovery of metal ions from aqueous streams

International Nuclear Information System (INIS)

Smith, B.F.; Robison, T.W.; Jarvinen, G.D.

1997-01-01

The use of water-soluble metal-binding polymers coupled with ultrafiltration (UF) is a technology under development to selectively concentrate and recover valuable or regulated metal-ions from dilute process or waste waters. The polymers have a sufficiently large molecular size that they can be separated and concentrated using commercially available UF technology. The polymers can then be reused by changing the solution conditions to release the metal-ions, which are recovered in a concentrated form for recycle or disposal. Pilot-scale demonstrations have been completed for a variety of waste streams containing low concentrations of metal ions including electroplating wastes (zinc and nickel) and nuclear waste streams (plutonium and americium). Many other potential commercial applications exist including remediation of contaminated solids. An overview of both the pilot-scale demonstrated applications and small scale testing of this technology are presented

Water-soluble metal-binding polymers with ultrafiltration: A technology for the removal, concentration, and recovery of metal ions from aqueous streams

Energy Technology Data Exchange (ETDEWEB)

Smith, B.F.; Robison, T.W.; Jarvinen, G.D.

1997-12-31

The use of water-soluble metal-binding polymers coupled with ultrafiltration (UF) is a technology under development to selectively concentrate and recover valuable or regulated metal-ions from dilute process or waste waters. The polymers have a sufficiently large molecular size that they can be separated and concentrated using commercially available UF technology. The polymers can then be reused by changing the solution conditions to release the metal-ions, which are recovered in a concentrated form for recycle or disposal. Pilot-scale demonstrations have been completed for a variety of waste streams containing low concentrations of metal ions including electroplating wastes (zinc and nickel) and nuclear waste streams (plutonium and americium). Many other potential commercial applications exist including remediation of contaminated solids. An overview of both the pilot-scale demonstrated applications and small scale testing of this technology are presented.

Anti-diabetic and antihypertensive activities of two flaxseed protein hydrolysate fractions revealed following their simultaneous separation by electrodialysis with ultrafiltration membranes.

Science.gov (United States)

Doyen, Alain; Udenigwe, Chibuike C; Mitchell, Patricia L; Marette, André; Aluko, Rotimi E; Bazinet, Laurent

2014-02-15

Flaxseed protein hydrolysate has been fractionated by electrodialysis with two ultrafiltration membranes (20 and 50 kDa) stacked in the system for the recovery of two specific cationic peptide fractions (KCl-F1 and KCl-F2). After 360 min of treatment, peptide migration increased as a function of time in KCl compartments. Moreover, the use of two different ultrafiltration membrane allowed concentration of the 300-400 and 400-500 Da molecular weight range peptides in the KCl-F1 and KCl-F2 fractions, respectively, compared to the initial hydrolysate. After mass spectrometry analysis, higher amounts of low molecular weight peptides were recovered in the KCl-F2 compartment while relatively higher molecular weight peptides were more detected in the KCl-F1 compartment. Amino acid analysis showed that His, Lys and Arg were especially concentrated in the KCl compartments. Finally, glucose-transport assay demonstrated that the KCl-F2 fraction increased glucose uptake while oral administration of KCl-F1 and final FPH decreased systolic blood pressure. Copyright © 2013 Elsevier Ltd. All rights reserved.

Uranium aqueous speciation in the vicinity of the former uranium mining sites using the diffusive gradients in thin films and ultrafiltration techniques

Energy Technology Data Exchange (ETDEWEB)

Drozdzak, Jagoda, E-mail: jdrozdza@vub.ac.be [Analytical, Environmental and Geochemistry (AMGC), Vrije Universiteit Brussels (VUB), Pleinlaan 2, 1050 Brussels (Belgium); Leermakers, Martine; Gao, Yue; Elskens, Marc [Analytical, Environmental and Geochemistry (AMGC), Vrije Universiteit Brussels (VUB), Pleinlaan 2, 1050 Brussels (Belgium); Phrommavanh, Vannapha; Descostes, Michael [AREVA Mines – R& D Dpt., Tour AREVA, 1 Place Jean Millier, 92084 Paris La Défense (France)

2016-03-24

The performance of the Diffusive Gradients in Thin films (DGT) technique with Chelex{sup ®}-100, Metsorb™ and Diphonix{sup ®} as binding phases was evaluated in the vicinity of the former uranium mining sites of Chardon and L'Ecarpière (Loire-Atlantique department in western France). This is the first time that the DGT technique with three different binding agents was employed for the aqueous U determination in the context of uranium mining environments. The fractionation and speciation of uranium were investigated using a multi-methodological approach using filtration (0.45 μm, 0.2 μm), ultrafiltration (500 kDa, 100 kDa and 10 kDa) coupled to geochemical speciation modelling (PhreeQC) and the DGT technique. The ultrafiltration data showed that at each sampling point uranium was present mostly in the 10 kDa truly dissolved fraction and the geochemical modelling speciation calculations indicated that U speciation was markedly predominated by CaUO{sub 2}(CO{sub 3}){sub 3}{sup 2−}. In natural waters, no significant difference was observed in terms of U uptake between Chelex{sup ®}-100 and Metsorb™, while similar or inferior U uptake was observed on Diphonix{sup ®} resin. In turn, at mining influenced sampling spots, the U accumulation on DGT-Diphonix{sup ®} was higher than on DGT-Chelex{sup ®}-100 and DGT-Metsorb™, probably because their performance was disturbed by the extreme composition of the mining waters. The use of Diphonix{sup ®} resin leads to a significant advance in the application and development of the DGT technique for determination of U in mining influenced environments. This investigation demonstrated that such multi-technique approach provides a better picture of U speciation and enables to assess more accurately the potentially bioavailable U pool. - Highlights: • The applicability of the DGT technique in the vicinity of former uranium mining sites was evaluated. • The binding selectivity order of the binding phase is

Surface and 60 FSW Performance Testing of the Modified MBS 2000 Closed Circuit Oxygen Rebreather

National Research Council Canada - National Science Library

Fothergill, David

2007-01-01

... into the system during a treatment. Since all previous testing had been performed at 1 ATA, a second major objective for the FY06 tests was to evaluate the modified MBS 2000 rebreather at 60 fsw in a hyperbaric chamber...

46 CFR 54.20-5 - Welding qualification tests and production testing (modifies UW-26, UW-28, UW-29, UW-47, and UW-48).

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Welding qualification tests and production testing... OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PRESSURE VESSELS Fabrication by Welding § 54.20-5 Welding qualification tests and production testing (modifies UW-26, UW-28, UW-29, UW-47, and UW-48). (a...

Testing modified gravity with globular clusters: the case of NGC 2419

Science.gov (United States)

Llinares, Claudio

2018-05-01

The dynamics of globular clusters has been studied in great detail in the context of general relativity as well as with modifications of gravity that strongly depart from the standard paradigm such as Modified Newtonian Dynamics. However, at present there are no studies that aim to test the impact that less extreme modifications of gravity (e.g. models constructed as alternatives to dark energy) have on the behaviour of globular clusters. This Letter presents fits to the velocity dispersion profile of the cluster NGC 2419 under the symmetron-modified gravity model. The data show an increase in the velocity dispersion towards the centre of the cluster which could be difficult to explain within general relativity. By finding the best-fitting solution associated with the symmetron model, we show that this tension does not exist in modified gravity. However, the best-fitting parameters give a model that is inconsistent with the dynamics of the Solar system. Exploration of different screening mechanisms should give us the chance to understand if it is possible to maintain the appealing properties of the symmetron model when it comes to globular clusters and at the same time recover the Solar system dynamics properly.

Hot corrosion testing of Ni-based alloys and coatings in a modified Dean rig

Science.gov (United States)

Steward, Jason Reid

Gas turbine blades are designed to withstand a variety of harsh operating conditions. Although material and coating improvements are constantly administered to increase the mean time before turbine refurbishment or replacement, hot corrosion is still considered as the major life-limiting factor in many industrial and marine gas turbines. A modified Dean rig was designed and manufactured at Tennessee Technological University to simulate the accelerated hot corrosion conditions and to conduct screening tests on the new coatings on Ni-based superalloys. Uncoated Ni-based superalloys, Rene 142 and Rene 80, were tested in the modified Dean rig to establish a testing procedure for Type I hot corrosion. The influence of surface treatments on the hot corrosion resistance was then investigated. It was found that grit-blasted specimens showed inferior hot corrosion resistance than that of the polished counterpart. The Dean rig was also used to test model MCrAlY alloys, pack cementation NiAl coatings, and electro-codeposited MCrAlY coatings. Furthermore, the hot corrosion attack on the coated-specimens were also assessed using a statistical analysis approach.

Comparison of acidic polymers for the removal of cobalt from water solutions by polymer assisted ultrafiltration

Energy Technology Data Exchange (ETDEWEB)

Dambies, Laurent, E-mail: chemjobs@netcourrir.com [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland); Jaworska, Agnieszka, E-mail: a.jaworska@ichtj.waw.pl [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland); Zakrzewska-Trznadel, Grazyna; Sartowska, Bozena [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland)

2010-06-15

In this study, three sulfonated water-soluble polymers based on poly(vinyl alcohol) of different molecular weights (10,000, 50,000 and 100,000 Da) were prepared and tested against commercially available poly(acrylic acid) for the removal of cobalt using polymer assisted ultrafiltration. High rejection rates were obtained between pH 3 and 6 with sulfonated poly(vinyl alcohol) (PVA 10,000 and 50,000 Da) whereas poly(acrylic acid) (PAA) of similar molecular weights performed rather poorly in this pH range. Sulfonation improved significantly sorption capability of PVA. Sulfonated PVA 10,000 was the best complexing agent with rejection rate above 95% between pH 3 and 6. For unmodified PVA the rejection rate was only 30-45% at pH 6 and there was no rejection at pH 3 at all. PAA rejection rate was above 90% at pH 6 and only about 10% at pH 3. Large scale experiment in cross-flow, continuous apparatus conducted by using PVA-SO{sub 3}H 10,000 Da to remove {sup 60}Co radioisotope from water solutions showed excellent results demonstrating the potential of this polymer to purify acidic radioactive wastes containing cobalt radioisotopes.

O teste de frio sem solo em sementes de abóbora The modified cold germination test in squash seeds

Directory of Open Access Journals (Sweden)

Derblai Casaroli

2006-12-01

Full Text Available Este trabalho teve como objetivo determinar o período de exposição à baixa temperatura no teste de frio sem solo, para avaliação de diferentes potenciais fisiológicos em lotes de sementes de abóbora. Foram avaliados seis lotes de sementes de abóbora cultivar "Menina Brasileira" (Cucurbita moschata Duch. produzidas na safra 2003/2004. As sementes foram submetidas a diferentes períodos (três, cinco, sete e nove dias de exposição à baixa temperatura para condução do teste de frio sem solo, a uma temperatura constante de 10°C. Utilizou-se o delineamento inteiramente casualizado, em que os tratamentos constituíram um fatorial 6x4 (seis lotes e quatro períodos de exposição, com quatro repetições de 50 sementes. As médias foram comparadas pelo teste de Tukey em nível de 5% de probabilidade de erro. Realizou-se também o teste de correlação simples de Pearson .Os resultados permitiram concluir que o período de três dias de exposição à baixa temperatura foi o mais indicado para a condução do teste de frio sem solo em sementes de abóbora.This research was aimed at determining the exposition period at low temperature in the modified cold germination test, to evaluate physiological potential of squash seed lots. Six seed lots of squash, variety Menina Brasileira (Cucurbita moschata Duch., produced in 2003/2004, were submitted at different exposition times for the development of the cold test. The modified cold gernation test was carried out at 10°C of constant temperature, during exposition time of three, five, seven and nine days. A completely randomized desing was used to the cold test, 0 constituting a factorial 6x4, corresponding to the six seed lots and four exposition time (3, 5, 7, and 9 days, with four repetitions. The averages were compared by the Tukey test, at 5% of probability. The correlation test of Person (r was used too. For the modified cold germination test, the period of three days was the most

PEP Run Report for Simulant Shakedown/Functional Testing

Energy Technology Data Exchange (ETDEWEB)

Josephson, Gary B.; Geeting, John GH; Bredt, Ofelia P.; Burns, Carolyn A.; Golovich, Elizabeth C.; Guzman-Leong, Consuelo E.; Kurath, Dean E.; Sevigny, Gary J.

2009-12-29

Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Waste Treatment Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed, and operated as part of a plan to respond to issue M12, "Undemonstrated Leaching Processes." The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing. Two operating scenarios are currently being evaluated for the ultrafiltration process (UFP) and leaching operations. The first scenario has caustic leaching performed in the UFP-2 ultrafiltration feed vessels (i.e., vessel UFP-VSL-T02A in the PEP; and vessels UFP-VSL-00002A and B in the WTP PTF). The second scenario has caustic leaching conducted in the UFP-1 ultrafiltration feed preparation vessels (i.e., vessels UFP-VSL-T01A and B in the PEP; vessels UFP-VSL-00001A and B in the WTP PTF). In both scenarios, 19-M sodium hydroxide solution (NaOH, caustic) is added to the waste slurry in the vessels to leach solid aluminum compounds (e.g., gibbsite, boehmite). Caustic addition is followed by a heating step that uses direct injection of steam to accelerate the leach process. Following the caustic leach, the vessel contents are cooled using vessel cooling jackets and/or external heat exchangers. The main difference between the two scenarios is that for leaching in UFP-1, the 19-M NaOH is added to un-concentrated waste slurry (3-8 wt% solids), while for leaching in UFP-2, the slurry is concentrated to nominally 20 wt% solids using cross-flow ultrafiltration

Tangential flow ultrafiltration for detection of white spot syndrome virus (WSSV) in shrimp pond water.

Science.gov (United States)

Alavandi, S V; Ananda Bharathi, R; Satheesh Kumar, S; Dineshkumar, N; Saravanakumar, C; Joseph Sahaya Rajan, J

2015-06-15

Water represents the most important component in the white spot syndrome virus (WSSV) transmission pathway in aquaculture, yet there is very little information. Detection of viruses in water is a challenge, since their counts will often be too low to be detected by available methods such as polymerase chain reaction (PCR). In order to overcome this difficulty, viruses in water have to be concentrated from large volumes of water prior to detection. In this study, a total of 19 water samples from aquaculture ecosystem comprising 3 creeks, 10 shrimp culture ponds, 3 shrimp broodstock tanks and 2 larval rearing tanks of shrimp hatcheries and a sample from a hatchery effluent treatment tank were subjected to concentration of viruses by ultrafiltration (UF) using tangential flow filtration (TFF). Twenty to 100l of water from these sources was concentrated to a final volume of 100mL (200-1000 fold). The efficiency of recovery of WSSV by TFF ranged from 7.5 to 89.61%. WSSV could be successfully detected by PCR in the viral concentrates obtained from water samples of three shrimp culture ponds, one each of the shrimp broodstock tank, larval rearing tank, and the shrimp hatchery effluent treatment tank with WSSV copy numbers ranging from 6 to 157mL(-1) by quantitative real time PCR. The ultrafiltration virus concentration technique enables efficient detection of shrimp viral pathogens in water from aquaculture facilities. It could be used as an important tool to understand the efficacy of biosecurity protocols adopted in the aquaculture facility and to carry out epidemiological investigations of aquatic viral pathogens. Copyright © 2015 Elsevier B.V. All rights reserved.

Influence of fertilizer draw solution properties on the process performance and microbial community structure in a side-stream anaerobic fertilizer-drawn forward osmosis – ultrafiltration bioreactor

KAUST Repository

Kim, Youngjin; Li, Sheng; Chekli, Laura; Phuntsho, Sherub; Ghaffour, NorEddine; Leiknes, TorOve; Shon, Ho Kyong

2017-01-01

In this study, a side-stream anaerobic fertilizer-drawn forward osmosis (FDFO) and ultrafiltration (UF) membrane bioreactor (MBR) hybrid system was proposed and operated for 55 days. The FDFO performance was first investigated in terms of flux

Determining fracture energy parameters of concrete from the modified compact tension test

Czech Academy of Sciences Publication Activity Database

Canteli, A.; Castañón, L.; Nieto, B.; Lozano, M.; Holušová, Táňa; Seitl, Stanislav

2014-01-01

Roč. 30, OCT (2014), s. 383-393 ISSN 1971-8993 R&D Projects: GA MŠk(CZ) EE2.3.20.0214 Grant - others:interní podpora AV ČR(CZ) M100411204 Institutional support: RVO:68081723 Keywords : Concrete fracture energy * Modified compact tension test * Concrete * Numerical simulation Subject RIV: JL - Materials Fatigue, Friction Mechanics

Polypropylene Track Membranes for Mikro and Ultrafiltration of Chemically Aggressive Agents

CERN Document Server

Kravets, L I; Apel, P Yu

2000-01-01

A production process for track membranes on the basis of chemically resistant polymer polypropylene has been developed. Research in all stages of the formation of the polypropylene track membranes has been conducted: the main principles of the process of chemical etching of polypropylene irradiated with accelerated ions have been investigated, the most effective structure of the etchant for a selective etching of the heavy ion tracks has been selected, the parameters of etching have been optimized. A method for sensibilization of latent tracks in polypropylene by effect of solvents has been developed. It helps to reach a significant increase in etching selectivity. A method for destruction of an absorbed chromocontaining layer on the surface of polypropylene track membranes formed during etching has been elaborated. Experimental samples of the membranes for micro and ultrafiltration have been obtained and their properties have been studied in course of their exploitation in chemically aggressive agents. For t...

Influence of gas-liquid two-phase flow on angiotensin-I converting enzyme inhibitory peptides separation by ultra-filtration.

Science.gov (United States)

Charoenphun, Narin; Youravong, Wirote

2017-01-01

Membrane fouling is a major problem in ultra-filtration systems and two-phase flow is a promising technique for permeate flux enhancement. The objective of this research was to study the use of an ultra-filtration (UF) system to enrich angiotensin-I converting enzyme (ACE) inhibitory peptides from tilapia protein hydrolysate. To select the most appropriate membrane and operating condition, the effects of membrane molecular weight cut-off (MWCO), transmembrane pressure (TMP) and cross-flow velocity (CFV) on permeate flux and ACE inhibitory peptide separation were studied. Additionally, the gas-liquid two-phase flow technique was applied to investigate its effect on the process capability. The results showed that the highest ACE inhibitory activity was obtained from permeate of the 1 kDa membrane. In terms of TMP and CFV, the permeate flux tended to increase with TMP and CFV. The use of gas-liquid two-phase flow as indicated by shear stress number could reduce membrane fouling and increase the permeate flux up to 42%, depending on shear stress number. Moreover, the use of a shear stress number of 0.039 led to an augmentation in ACE inhibitory activity of permeates. Operating conditions using a shear stress number of 0.039 were recommended for enrichment of ACE inhibitory peptides. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Tangential Flow Ultrafiltration Allows Purification and Concentration of Lauric Acid-/Albumin-Coated Particles for Improved Magnetic Treatment.

Science.gov (United States)

Zaloga, Jan; Stapf, Marcus; Nowak, Johannes; Pöttler, Marina; Friedrich, Ralf P; Tietze, Rainer; Lyer, Stefan; Lee, Geoffrey; Odenbach, Stefan; Hilger, Ingrid; Alexiou, Christoph

2015-08-14

Superparamagnetic iron oxide nanoparticles (SPIONs) are frequently used for drug targeting, hyperthermia and other biomedical purposes. Recently, we have reported the synthesis of lauric acid-/albumin-coated iron oxide nanoparticles SEON(LA-BSA), which were synthesized using excess albumin. For optimization of magnetic treatment applications, SPION suspensions need to be purified of excess surfactant and concentrated. Conventional methods for the purification and concentration of such ferrofluids often involve high shear stress and low purification rates for macromolecules, like albumin. In this work, removal of albumin by low shear stress tangential ultrafiltration and its influence on SEON(LA-BSA) particles was studied. Hydrodynamic size, surface properties and, consequently, colloidal stability of the nanoparticles remained unchanged by filtration or concentration up to four-fold (v/v). Thereby, the saturation magnetization of the suspension can be increased from 446.5 A/m up to 1667.9 A/m. In vitro analysis revealed that cellular uptake of SEON(LA-BSA) changed only marginally. The specific absorption rate (SAR) was not greatly affected by concentration. In contrast, the maximum temperature Tmax in magnetic hyperthermia is greatly enhanced from 44.4 °C up to 64.9 °C by the concentration of the particles up to 16.9 mg/mL total iron. Taken together, tangential ultrafiltration is feasible for purifying and concentrating complex hybrid coated SPION suspensions without negatively influencing specific particle characteristics. This enhances their potential for magnetic treatment.

Tests and Confidence Intervals for an Extended Variance Component Using the Modified Likelihood Ratio Statistic

DEFF Research Database (Denmark)

Christensen, Ole Fredslund; Frydenberg, Morten; Jensen, Jens Ledet

2005-01-01

The large deviation modified likelihood ratio statistic is studied for testing a variance component equal to a specified value. Formulas are presented in the general balanced case, whereas in the unbalanced case only the one-way random effects model is studied. Simulation studies are presented......, showing that the normal approximation to the large deviation modified likelihood ratio statistic gives confidence intervals for variance components with coverage probabilities very close to the nominal confidence coefficient....

Serum and plasma for total and free anticonvulsant drug analyses: effects on EMIT assays and ultrafiltration devices.

Science.gov (United States)

Godolphin, W; Trepanier, J; Farrell, K

1983-01-01

The suitability of serum and plasma anticoagulated with heparin, EDTA, citrate, or oxalate was assessed for analysis of free and total phenytoin, carbamazepine, and valproic acid. The free fraction was isolated by ultrafiltration through FreeLevel devices (Syva, Palo Alto, CA). Serum, heparin, and EDTA plasma were satisfactory for both free and total phenytoin and carbamazepine. EDTA could not be used for EMIT (Syva) analysis of valproate. Citrate and, to a lesser degree, oxalate cause a significant negative interference in the concentration of these three drugs as measured both by EMIT and gas-liquid chromatography.

Recovery of diverse microbes in high turbidity surface water samples using dead-end ultrafiltration.

Science.gov (United States)

Mull, Bonnie; Hill, Vincent R

2012-12-01

Dead-end ultrafiltration (DEUF) has been reported to be a simple, field-deployable technique for recovering bacteria, viruses, and parasites from large-volume water samples for water quality testing and waterborne disease investigations. While DEUF has been reported for application to water samples having relatively low turbidity, little information is available regarding recovery efficiencies for this technique when applied to sampling turbid water samples such as those commonly found in lakes and rivers. This study evaluated the effectiveness of a DEUF technique for recovering MS2 bacteriophage, enterococci, Escherichia coli, Clostridium perfringens, and Cryptosporidium parvum oocysts in surface water samples having elevated turbidity. Average recovery efficiencies for each study microbe across all turbidity ranges were: MS2 (66%), C. parvum (49%), enterococci (85%), E. coli (81%), and C. perfringens (63%). The recovery efficiencies for MS2 and C. perfringens exhibited an inversely proportional relationship with turbidity, however no significant differences in recovery were observed for C. parvum, enterococci, or E. coli. Although ultrafilter clogging was observed, the DEUF method was able to process 100-L surface water samples at each turbidity level within 60 min. This study supports the use of the DEUF method for recovering a wide array of microbes in large-volume surface water samples having medium to high turbidity. Published by Elsevier B.V.

Simultaneous determination of free calcium, magnesium, sodium and potassium ion concentrations in simulated milk ultrafiltrate and reconstituted skim milk using the Donnan Membrane Technique

NARCIS (Netherlands)

Gao, R.; Temminghoff, E.J.M.; Leeuwen, van H.P.; Valenberg, van H.J.F.; Eisner, M.D.; Boekel, van M.A.J.S.

2009-01-01

This study focused on determination of free Ca2+, Mg2+, Na+ and K+ concentrations in a series of CaCl2 solutions, simulated milk ultrafiltrate and reconstituted skim milk using a recently developed Donnan Membrane Technique (DMT). A calcium ion selective electrode was used to compare the DMT

EFRT M-12 Issue Resolution: Caustic Leach Rate Constants from PEP and Laboratory-Scale Tests

Energy Technology Data Exchange (ETDEWEB)

Mahoney, Lenna A.; Rassat, Scot D.; Eslinger, Paul W.; Aaberg, Rosanne L.; Aker, Pamela M.; Golovich, Elizabeth C.; Hanson, Brady D.; Hausmann, Tom S.; Huckaby, James L.; Kurath, Dean E.; Minette, Michael J.; Sundaram, S. K.; Yokuda, Satoru T.

2009-08-14

Testing Summary Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed and constructed and is to be operated as part of a plan to respond to issue M12, “Undemonstrated Leaching Processes.” The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing. Two operating scenarios are currently being evaluated for the ultrafiltration process (UFP) and leaching operations. The first scenario has caustic leaching performed in the UFP-2 ultrafiltration feed vessels (i.e., vessel UFP-VSL-T02A in the PEP and vessels UFP-VSL-00002A and B in the WTP PTF). The second scenario has caustic leaching conducted in the UFP-1 ultrafiltration feed preparation vessels (i.e., vessels UFP-VSL-T01A and B in the PEP; vessels UFP-VSL-00001A and B in the WTP PTF). In both scenarios, 19-M sodium hydroxide solution (NaOH, caustic) is added to the waste slurry in the vessels to leach solid aluminum compounds (e.g., gibbsite, boehmite). Caustic addition is followed by a heating step that uses direct injection of steam to accelerate the leaching process. Following the caustic leach, the vessel contents are cooled using vessel cooling jackets and/or external heat exchangers. The main difference between the two scenarios is that for leaching in UFP-1, the 19-M NaOH is added to un-concentrated waste slurry (3 to 8 wt% solids), while for leaching in UFP-2, the slurry is

EFRT M-12 Issue Resolution: Caustic Leach Rate Constants from PEP and Laboratory-Scale Tests

International Nuclear Information System (INIS)

Mahoney, Lenna A.; Rassat, Scot D.; Eslinger, Paul W.; Aaberg, Rosanne L.; Aker, Pamela M.; Golovich, Elizabeth C.; Hanson, Brady D.; Hausmann, Tom S.; Huckaby, James L.; Kurath, Dean E.; Minette, Michael J.; Sundaram, S. K.; Yokuda, Satoru T.

2009-01-01

Testing Summary Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed and constructed and is to be operated as part of a plan to respond to issue M12, 'Undemonstrated Leaching Processes.' The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing. Two operating scenarios are currently being evaluated for the ultrafiltration process (UFP) and leaching operations. The first scenario has caustic leaching performed in the UFP-2 ultrafiltration feed vessels (i.e., vessel UFP-VSL-T02A in the PEP and vessels UFP-VSL-00002A and B in the WTP PTF). The second scenario has caustic leaching conducted in the UFP-1 ultrafiltration feed preparation vessels (i.e., vessels UFP-VSL-T01A and B in the PEP; vessels UFP-VSL-00001A and B in the WTP PTF). In both scenarios, 19-M sodium hydroxide solution (NaOH, caustic) is added to the waste slurry in the vessels to leach solid aluminum compounds (e.g., gibbsite, boehmite). Caustic addition is followed by a heating step that uses direct injection of steam to accelerate the leaching process. Following the caustic leach, the vessel contents are cooled using vessel cooling jackets and/or external heat exchangers. The main difference between the two scenarios is that for leaching in UFP-1, the 19-M NaOH is added to un-concentrated waste slurry (3 to 8 wt% solids), while for leaching in UFP-2, the slurry is concentrated

PEP Integrated Test D Run Report Caustic and Oxidative Leaching in UFP-VSL-T02A

Energy Technology Data Exchange (ETDEWEB)

Sevigny, Gary J.; Bredt, Ofelia P.; Burns, Carolyn A.; Kurath, Dean E.; Geeting, John GH; Golovich, Elizabeth C.; Guzman-Leong, Consuelo E.; Josephson, Gary B.

2009-12-11

Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed and operated as part of a plan to respond to issue M12, "Undemonstrated Leaching Processes" of the External Flowsheet Review Team (EFRT) issue response plan. The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing. Two operating scenarios are currently being evaluated for the ultrafiltration process (UFP) and leaching operations. The first scenario (Test B and D) has caustic leaching performed in the UFP-2 ultrafiltration feed vessels (i.e., vessel UFP-VSL-T02A in the PEP and vessels UFP-VSL-00002A and B in the WTP PTF). The second scenario (Test A) has caustic leaching conducted in the UFP-1 ultrafiltration feed preparation vessels (i.e., vessels UFP-VSL-T01A and B in the PEP and vessels UFP VSL-00001A and B in the WTP PTF). In Test D, 19M sodium hydroxide (NaOH, caustic) was added to the waste slurry in the UFP VSL T02 vessel after the solids were concentrated to ~20% undissolved solids. The NaOH was added to leach solid aluminum compounds (e.g., gibbsite, boehmite). Caustic addition is followed by heating to 85°C using direct injection of steam to accelerate the leach process. The main difference of Test D compared to Test B is that the leach temperature is 85°C for 24 hrs as compared to 100°C for 12 hours. The other difference is the Test D simulant had Cr in the

Performance study of ultrafiltration membrane with bovine serum albumin as feed solution

International Nuclear Information System (INIS)

Syahril Ahmad

2009-01-01

Bovine serum albumin solutions at different temperature, pH, flow rate and operation pressure have been used as feed solution for studying performance of ultrafiltration membrane. Polysulfone membranes used for this experiment were in form of hollow fibers that have Molecular Weight Cut Off (MWCO) 60 kDa. Observation was focused on flux parameter and rejection coefficient towards protein during the process. Result shows that temperature, pH of BSA feed solution, flow rate and operation pressure can affect the flux and rejection coefficient of membrane. High temperature feed solution tend to decrease the flux but increase rejection coefficient. Rejection coefficient of membrane will increase while flux decreasing at pH of feed solution near to protein isoelectric point. High pressure of feed solution will increase flux but decrease rejection of membrane. Rejection of membrane will decrease and flux will increase when the process operated in slow flow rate. (author)

A synergetic analysis method for antifouling behavior investigation on PES ultrafiltration membrane with self-assembled TiO2 nanoparticles.

Science.gov (United States)

Li, Xin; Li, Jiansheng; Fang, Xiaofeng; Bakzhan, Kariboz; Wang, Lianjun; Van der Bruggen, Bart

2016-05-01

Fouling of ultrafiltration (UF) membranes is a major impediment for their use in drinking water production. Mixed matrix membranes (MMMs) may have great opportunities in dealing with this challenge due to their hierarchical structures and multiple functionalities. In this study, a synergetic analysis method based on intermolecular adhesion force measurement and fouling process simulation was applied to investigate the fouling mechanism of polyethersulfone (PES) UF membranes containing in situ self-assembled TiO2 nanoparticles (NPs). The fouling resistance behavior and antifouling mechanism of the newly developed composite membranes were investigated with sodium alginate (SA), bovine serum albumin (BSA) and humic acid (HA) as model organic foulants. An improved antifouling effect was conspicuously observed for the composite membranes, expressed by a lower flux decline and significantly better cleaning efficiency. A strong correlation between the self-assembled structure of TiO2 NPs and the antifouling behavior of the composite membrane was observed. A lower magnitude and a narrower distribution of adhesion forces for the composite membrane suggest the effective suppression of foulants adsorption on the clean or fouled membrane. The simulation analysis indicates that the main fouling mechanism was standard blocking and cake filtration, further confirming the superiority of the NPs self-assembled structure in mitigating membrane fouling. This dual analysis method may provide a promising technological support for the application of modified UF membranes with self-assembled NPs in drinking water production. Copyright © 2016 Elsevier Inc. All rights reserved.

Evaluation of Membrane Ultrafiltration and Residual Chlorination as a Decentralized Water Treatment Strategy for Ten Rural Healthcare Facilities in Rwanda

Directory of Open Access Journals (Sweden)

Alexandra Huttinger

2015-10-01

Full Text Available There is a critical need for safe water in healthcare facilities (HCF in low-income countries. HCF rely on water supplies that may require additional on-site treatment, and need sustainable technologies that can deliver sufficient quantities of water. Water treatment systems (WTS that utilize ultrafiltration membranes for water treatment can be a useful technology in low-income countries, but studies have not systematically examined the feasibility of this technology in low-income settings. We monitored 22 months of operation of 10 WTS, including pre-filtration, membrane ultrafiltration, and chlorine residual disinfection that were donated to and operated by rural HCF in Rwanda. The systems were fully operational for 74% of the observation period. The most frequent reasons for interruption were water shortage (8% and failure of the chlorination mechanism (7%. When systems were operational, 98% of water samples collected from the HCF taps met World Health Organization (WHO guidelines for microbiological water quality. Water quality deteriorated during treatment interruptions and when water was stored in containers. Sustained performance of the systems depended primarily on organizational factors: the ability of the HCF technician to perform routine servicing and repairs, and environmental factors: water and power availability and procurement of materials, including chlorine and replacement parts in Rwanda.

Fate of antibiotics in activated sludge followed by ultrafiltration (CAS-UF) and in a membrane bioreactor (MBR).

Science.gov (United States)

Sahar, Eyal; Messalem, Rami; Cikurel, Haim; Aharoni, Avi; Brenner, Asher; Godehardt, Manuel; Jekel, Martin; Ernst, Mathias

2011-10-15

The fates of several macrolide, sulphonamide, and trimethoprim antibiotics contained in the raw sewage of the Tel-Aviv wastewater treatment plant (WWTP) were investigated after the sewage was treated using either a full-scale conventional activated sludge (CAS) system coupled with a subsequent ultrafiltration (UF) step or a pilot membrane bioreactor (MBR) system. Antibiotics removal in the MBR system, once it achieved stable operation, was 15-42% higher than that of the CAS system. This advantage was reduced to a maximum of 20% when a UF was added to the CAS. It was hypothesized that the contribution of membrane separation (in both systems) to antibiotics removal was due either to sorption to biomass (rather than improvement in biodegradation) or to enmeshment in the membrane biofilm (since UF membrane pores are significantly larger than the contaminant molecules). Batch experiments with MBR biomass showed a markedly high potential for sorption of the tested antibiotics onto the biomass. Moreover, methanol extraction of MBR biomass released significant amounts of sorbed antibiotics. This finding implies that more attention must be devoted to the management of excess sludge. Copyright © 2011 Elsevier Ltd. All rights reserved.

Cyclic Testing of the 6-Strand Tang and Modified Lim-Tsai Flexor Tendon Repair Techniques.

Science.gov (United States)

Kang, Gavrielle Hui-Ying; Wong, Yoke-Rung; Lim, Rebecca Qian-Ru; Loke, Austin Mun-Kitt; Tay, Shian-Chao

2018-03-01

In this study, we compared the Tang repair technique with the 6-strand modified Lim-Tsai repair technique under cyclic testing conditions. Twenty fresh-frozen porcine flexor tendons were randomized into 2 groups for repair with either the modified Lim-Tsai or the Tang technique using Supramid 4-0 core sutures and Ethilon 6-0 epitendinous running suture. The repaired tendons were subjected to 2 stage cyclic loading. The survival rate and gap formation at the repair site were recorded. Tendons repaired by the Tang technique achieved an 80% survival rate. None of the modified Lim-Tsai repairs survived. The mean gap formed at the end of 1000 cycles was 1.09 mm in the Tang repairs compared with 4.15 mm in the modified Lim-Tsai repairs. The Tang repair is biomechanically stronger than the modified Lim-Tsai repair under cyclic loading. The Tang repair technique may exhibit a higher tolerance for active mobilization after surgery with less propensity for gap formation. Copyright © 2018 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Fouling behavior of poly(ether)sulfone ultrafiltration membrane during concentration of whey proteins: Effect of hydrophilic modification using atmospheric pressure argon jet plasma.

Science.gov (United States)

Damar Huner, Irem; Gulec, Haci Ali

2017-12-01

The aim of the study was to investigate the effects of hydrophilic surface modification via atmospheric pressure jet plasma (ApJPls) on the fouling propensity of polyethersulfone (PES) ultrafiltration (UF) membranes during concentration of whey proteins. The distance from nozzle to substrate surface of 30mm and the exposure period of 5 times were determined as the most effective parameters enabling an increase in ΔG iwi value of the plain membrane from (-) 14.92±0.89mJ/m 2 to (+) 17.57±0.67mJ/m 2 . Maximum hydrophilicity and minimum surface roughness achieved by argon plasma action resulted in better antifouling behavior, while the hydraulic permeability and the initial permeate flux were decreased sharply due to the plasma-induced surface cross-linking. A quite steady state flux was obtained throughout the UF with the ApJPls modified PES membrane. The contribution of R frev to R t , which was 94% for the UF through the plain membrane, decreased to 43% after the plasma treatment. The overall results of this study highlighted the ApJPls modification decreased the fouling propensity of PES membrane without affecting the original protein rejection capability and improved the recovery of initial permeate flux after chemical cleaning. Copyright © 2017 Elsevier B.V. All rights reserved.

Removal of trace organic chemicals and performance of a novel hybrid ultrafiltration-osmotic membrane bioreactor.

Science.gov (United States)

Holloway, Ryan W; Regnery, Julia; Nghiem, Long D; Cath, Tzahi Y

2014-09-16

A hybrid ultrafiltration-osmotic membrane bioreactor (UFO-MBR) was investigated for over 35 days for nutrient and trace organic chemical (TOrC) removal from municipal wastewater. The UFO-MBR system uses both ultrafiltration (UF) and forward osmosis (FO) membranes in parallel to simultaneously extract clean water from an activated sludge reactor for nonpotable (or environmental discharge) and potable reuse, respectively. In the FO stream, water is drawn by osmosis from activated sludge through an FO membrane into a draw solution (DS), which becomes diluted during the process. A reverse osmosis (RO) system is then used to reconcentrate the diluted DS and produce clean water suitable for direct potable reuse. The UF membrane extracts water, dissolved salts, and some nutrients from the system to prevent their accumulation in the activated sludge of the osmotic MBR. The UF permeate can be used for nonpotable reuse purposes (e.g., irrigation and toilet flushing). Results from UFO-MBR investigation illustrated that the chemical oxygen demand, total nitrogen, and total phosphorus removals were greater than 99%, 82%, and 99%, respectively. Twenty TOrCs were detected in the municipal wastewater that was used as feed to the UFO-MBR system. Among these 20 TOrCs, 15 were removed by the hybrid UFO-MBR system to below the detection limit. High FO membrane rejection was observed for all ionic and nonionic hydrophilic TOrCs and lower rejection was observed for nonionic hydrophobic TOrCs. With the exceptions of bisphenol A and DEET, all TOrCs that were detected in the DS were well rejected by the RO membrane. Overall, the UFO-MBR can operate sustainably and has the potential to be utilized for direct potable reuse applications.

STELLAR STRUCTURE AND TESTS OF MODIFIED GRAVITY

International Nuclear Information System (INIS)

Chang, Philip; Hui, Lam

2011-01-01

Theories that attempt to explain cosmic acceleration by modifying gravity typically introduces a long-range scalar force that needs to be screened on small scales. One common screening mechanism is the chameleon, where the scalar force is screened in environments with a sufficiently deep gravitational potential, but acts unimpeded in regions with a shallow gravitational potential. This leads to a variation in the overall gravitational G with environment. We show that such a variation can occur within a star itself, significantly affecting its evolution and structure, provided that the host galaxy is unscreened. The effect is most pronounced for red giants, which would be smaller by a factor of tens of percent and thus hotter by hundreds of Kelvin, depending on the parameters of the underlying scalar-tensor theory. Careful measurements of these stars in suitable environments (nearby dwarf galaxies not associated with groups or clusters) would provide constraints on the chameleon mechanism that are four orders of magnitude better than current large-scale structure limits and two orders of magnitude better than present solar system tests.

Study and optimization of the ultrasound-enhanced cleaning of an ultrafiltration ceramic membrane through a combined experimental-statistical approach.

Science.gov (United States)

Alventosa-deLara, E; Barredo-Damas, S; Alcaina-Miranda, M I; Iborra-Clar, M I

2014-05-01

Membrane fouling is one of the main drawbacks of ultrafiltration technology during the treatment of dye-containing effluents. Therefore, the optimization of the membrane cleaning procedure is essential to improve the overall efficiency. In this work, a study of the factors affecting the ultrasound-assisted cleaning of an ultrafiltration ceramic membrane fouled by dye particles was carried out. The effect of transmembrane pressure (0.5, 1.5, 2.5 bar), cross-flow velocity (1, 2, 3 ms(-1)), ultrasound power level (40%, 70%, 100%) and ultrasound frequency mode (37, 80 kHz and mixed wave) on the cleaning efficiency was evaluated. The lowest frequency showed better results, although the best cleaning performance was obtained using the mixed wave mode. A Box-Behnken Design was used to find the optimal conditions for the cleaning procedure through a response surface study. The optimal operating conditions leading to the maximum cleaning efficiency predicted (32.19%) were found to be 1.1 bar, 3 ms(-1) and 100% of power level. Finally, the optimized response was compared to the efficiency of a chemical cleaning with NaOH solution, with and without the use of ultrasound. By using NaOH, cleaning efficiency nearly triples, and it improves up to 25% by adding ultrasound. Copyright © 2013 Elsevier B.V. All rights reserved.

Detection of Genetically Modified Food: Has Your Food Been Genetically Modified?

Science.gov (United States)

Brandner, Diana L.

2002-01-01

Explains the benefits and risks of genetically-modified foods and describes methods for genetically modifying food. Presents a laboratory experiment using a polymerase chain reaction (PCR) test to detect foreign DNA in genetically-modified food. (Contains 18 references.) (YDS)

Effects of Modified Multistage Field Test on Performance and Physiological Responses in Wheelchair Basketball Players

Science.gov (United States)

Weissland, Thierry; Faupin, Arnaud; Borel, Benoit; Berthoin, Serge; Leprêtre, Pierre-Marie

2015-01-01

A bioenergetical analysis of manoeuvrability and agility performance for wheelchair players is inexistent. It was aimed at comparing the physiological responses and performance obtained from the octagon multistage field test (MFT) and the modified condition in “8 form” (MFT-8). Sixteen trained wheelchair basketball players performed both tests in randomized condition. The levels performed (end-test score), peak values of oxygen uptake (VO2peak), minute ventilation (VEpeak), heart rate (HRpeak), peak and relative blood lactate (Δ[Lact−] = peak – rest values), and the perceived rating exertion (RPE) were measured. MFT-8 induced higher VO2peak and VEpeak values compared to MFT (VO2peak: 2.5 ± 0.6 versus 2.3 ± 0.6 L·min−1 and VEpeak: 96.3 ± 29.1 versus 86.6 ± 23.4 L·min−1; P physiological responses than MFT. It could be explained by demands of wheelchair skills occurring in 8 form during the modified condition. PMID:25802841

Effects of modified multistage field test on performance and physiological responses in wheelchair basketball players.

Science.gov (United States)

Weissland, Thierry; Faupin, Arnaud; Borel, Benoit; Berthoin, Serge; Leprêtre, Pierre-Marie

2015-01-01

A bioenergetical analysis of manoeuvrability and agility performance for wheelchair players is inexistent. It was aimed at comparing the physiological responses and performance obtained from the octagon multistage field test (MFT) and the modified condition in "8 form" (MFT-8). Sixteen trained wheelchair basketball players performed both tests in randomized condition. The levels performed (end-test score), peak values of oxygen uptake (VO2peak), minute ventilation (VEpeak), heart rate (HRpeak), peak and relative blood lactate (Δ[Lact(-)] = peak--rest values), and the perceived rating exertion (RPE) were measured. MFT-8 induced higher VO2peak and VEpeak values compared to MFT (VO2peak: 2.5 ± 0.6 versus 2.3 ± 0.6 L · min(-1) and VEpeak: 96.3 ± 29.1 versus 86.6 ± 23.4 L · min(-1); P < 0.05) with no difference in other parameters. Significant relations between VEpeak and end-test score were correlated for both field tests (P < 0.05). At exhaustion, MFT attained incompletely VO2peak and VEpeak. Among experienced wheelchair players, MFT-8 had no effect on test performance but generates higher physiological responses than MFT. It could be explained by demands of wheelchair skills occurring in 8 form during the modified condition.

Flux, rejection and fouling during microfiltration and ultrafiltration of sugar palm sap using a pilot plant scale

Directory of Open Access Journals (Sweden)

Wanichapichart, P.

2006-07-01

Full Text Available The possibility of using a pilot plant scale microfiltration (MF and ultrafiltration (UF to clarify and reduce number of bacteria, yeast and mould of sugar palm sap was studied. The membrane used was multi channel tubular ceramic membrane (ZrO2-TiO2 with membrane pore size 0.2 and 0.1 μm and molecular weight cut off (MWCO 300 and 50 kDa for microfiltration and ultrafiltration respectively. The experiment was carried out to investigate the rejection of the components in sugar palm sap, permeate flux and fouling characteristics. The results showed that the turbidity, the total solid, the viscosity and the numbers of bacteria, yeast and mould in the permeate obtained by MF and UF were reduced significantly compared to those of fresh sugar palm sap. The total soluble solid, total sugar, reducing sugar and pH were not affected by MF and UF. The permeate fluxes for all membranes were reduced greatly as the volume concentration ratio (VCR increased due to severe fouling. The irreversible fouling on membrane surface and/or inside the membrane tended to increase with increasing membrane pore size or MWCO. The result also suggested that protein and small particle in the sugar palm sap were probably responsible for the internal fouling of large pore size membrane. According to the physical, chemical and microorganism quality results, both MF and UF showed the potential use for improving the quality of sugar palm sap but flux reduction due to fouling was a major problem affecting the process performance.

Applicability of modified burst test data to reactivity initiated accident

Energy Technology Data Exchange (ETDEWEB)

Yueh, K., E-mail: yuehky@hotmail.com

2017-05-15

A comprehensive irradiated cladding mechanical property dataset was generated by a recently developed modified burst test (MBT) under reactivity initiated accident (RIA) loading conditions [1,2]. The test data contains a wide range of test conditions that could bridge the gap between fast transient test reactor data (short pulse and/or low temperature) and prototypical commercial reactor conditions. This paper documents an evaluation performed to demonstrate the applicability of the MBT data to fuel cladding performance under RIA conditions. The current effort includes a comparison of calculated fuel cladding failure/burst strain for tests conducted at the Japan Atomic Energy Agency's (JAEA) Nuclear Safety Research Reactor (NSRR) to the MBT dataset, and an evaluation of potential mechanisms on how some NSRR tests survived beyond the cladding loading capacity. A simple shell model, coupled with temperature output from the Falcon fuel performance code, was used to calculate the fuel pellet thermal expansion of NSRR tests at the point of failure. The calculated fuel pellet thermal expansion correlates well directly with the MBT data at similar loading conditions. A 3-dimensional (3D) finite element analysis (FEA) model was used to evaluate fuel movement potential during a RIA. The evaluation indicates fuel relocation into the pellet chamfer and later into the dish is possible once a temperature threshold is reached before cladding failure and thus could significantly increase the fuel rod energy absorption capacity in a RIA event.

HRR Upgrade to mass loss calorimeter and modified Schlyter test for FR Wood

Science.gov (United States)

Mark A. Dietenberger; Charles R. Boardman

2013-01-01

Enhanced Heat Release Rate (HRR) methodology has been extended to the Mass Loss Calorimeter (MLC) and the Modified Schlyter flame spread test to evaluate fire retardant effectiveness used on wood based materials. Modifications to MLC include installation of thermopile on the chimney walls to correct systematic errors to the sensible HRR calculations to account for...

Whey protein concentration by ultrafiltration and study of functional properties

Directory of Open Access Journals (Sweden)

Sidiane Iltchenco

2018-06-01

Full Text Available ABSTRACT: This paper aim to evaluate the ultrafiltration (UF process for constituents recovery from whey. Sequences of factorial designs were performed by varying temperature (5 to 40°C and pressure (1 to 3 bar, to maximize the proteins concentration using membrane of 100kDa in dead end system. Based on the best result new experiments were performed with membrane of 50kDa and 10kDa. With the membrane of 50 the protein retention was about 3 times higher than the membrane of 100kDa. The concentrated obtained by UF membrane of 10kDa, 10°C and 2 bar in laboratory scale showed a mean protein retention of 80 %, greater protein solubility, emulsion stability and the identification of β-lactoglobulins (18.3 kDa and α-lactalbumin fractions (14.2kDa. Therefore, the use of membrane of 100 and 50kDa are became a industrially recommendable alternatives to concentration of whey proteins, and/or as a previous step to the fractionation of whey constituents using membrane ≤10kDa, aiming at future applications in different areas (food, pharmaceutical, chemical, etc..

Ultrafiltration and valorisation of lignin in black liquor from South African Kraft mills: A focus on dead-end stirred cell filtration

CSIR Research Space (South Africa)

Kekana, PT

2014-07-01

Full Text Available stream_source_info Kekana_2014_ABSTRACT.pdf.txt stream_content_type text/plain stream_size 1098 Content-Encoding ISO-8859-1 stream_name Kekana_2014_ABSTRACT.pdf.txt Content-Type text/plain; charset=ISO-8859-1 2014... International Conference on Chemical Thermodynamics and South African Institution of Chemical Engineering Conference, Durban International Convention Centre in Durban, South Africa, 27 July - 01 August 2014 Ultrafiltration and valorisation of lignin...

Removal of radionuclides in drinking water by membrane treatment using ultrafiltration, reverse osmosis and electrodialysis reversal.

Science.gov (United States)

Montaña, M; Camacho, A; Serrano, I; Devesa, R; Matia, L; Vallés, I

2013-11-01

A pilot plant had been built to test the behaviour of ultrafiltration (UF), reverse osmosis (RO), and electrodialysis reversal (EDR) in order to improve the quality of the water supplied to Barcelona metropolitan area from the Llobregat River. This paper presents results from two studies to reduce natural radioactivity. The results from the pilot plant with four different scenarios were used to design the full-scale treatment plant built (SJD WTP). The samples taken at different steps of the treatment were analysed to determine gross alpha, gross beta and uranium activity. The results obtained revealed a significant improvement in the radiological water quality provided by both membrane techniques (RO and EDR showed removal rates higher than 60%). However, UF did not show any significant removal capacity for gross alpha, gross beta or uranium activities. RO was better at reducing the radiological parameters studied and this treatment was selected and applied at the full scale treatment plant. The RO treatment used at the SJD WTP reduced the concentration of both gross alpha and gross beta activities and also produced water of high quality with an average removal of 95% for gross alpha activity and almost 93% for gross beta activity at the treatment plant. Copyright © 2013 Elsevier Ltd. All rights reserved.

Ultrafiltration membranes from waste polyethylene terephthalate and additives: synthesis and characterization

Directory of Open Access Journals (Sweden)

Smitha Rajesh

2014-01-01

Full Text Available The synthesis and characterization of asymmetric ultrafiltration membranes from recycled polyethylene terephthalate (PET and polyvinylpyrrolidone (PVP is reported. PET is currently used in many applications, including the manufacture of bottles and tableware. Monomer extraction from waste PET is expensive, and this process has not yet been successfully demonstrated on a viable scale. Hence, any method to recycle or regenerate PET once it has been used is of significant importance from scientific and environmental research viewpoints. Such a process would be a green alternative due to reduced raw monomer consumption and the additional benefit of reduced manufacturing costs. The membranes described here were prepared by a phase-inversion process, which involved casting a solution containing PET, m-cresol as solvent, and polyethylene glycol (PEG of different molecular weights as additives. The membranes were characterized in terms of pure water permeability (PWP, molecular weight cut-off (MWCO, and flux and membrane morphology. The results show that the addition of PEG with high molecular weights leads to membranes with higher PWP. The presence of additives affects surface roughness and membrane morphology.

Morphology and performance of polyvinylidene fluoride/perfluoro sulphonic acid hollow fiber ultrafiltration blend membranes

International Nuclear Information System (INIS)

Yuan, Guo-Lin; Xu, Zhen-Liang; Wei, Yong-Ming; Yu, Li-Yun

2009-01-01

Polyvinylidene fluoride-perfluoro sulphonic acid hollow fibre ultrafiltration blend membranes were prepared by wet-spinning method. Polyvinylpyrrolidone and ethanol aqueous solutions were employed as additive and coagulants, respectively. The effect of Polyvinylpyrrolidone concentration in the dopes and ethanol concentration in the coagulants on morphology and performance of Polyvinylidene fluoride -perfluoro sulphonic acid hollow fibre ultrafiltration blend membranes were investigated. Blend membranes were characterized in terms of precipitation kinetics, morphology, thermal property and separation performance. The results showed that the increments of Polyvinylpyrrolidone concentration in the dopes and ethanol concentration in coagulants both resulted in higher pure water permeation flux and worse rejection (R) of bovine serum albumin (with the increment of Polyvinylpyrrolidone concentration from 0 to 5 wt% in the dopes, pure water permeation increased from 41.7 L.m -2 .h -1 to 134 L.m -2 .h -1 and R decreased from 99.8% to 84.4% as well as with the increase in ethanol concentration in coagulants from 0 to 40 wt%, pure water permeation increased from 33.5 L.m -2 .h- 1 to 123 L.m -2 .h -1 and R decreased from 97.7% to 88.7%). However, the proportion of sponge-like structure in the cross-section of membranes decreased with the increasing Polyvinylpyrrolidone concentration in the dopes and the proportion increased with the increased ethanol concentration in the coagulations. In addition, the location of the sponge-like structure in the cross-section of membranes was significantly influenced by ethanol concentrations in the coagulants and differential scanning calorimeter results revealed that the crystallinity (X c ) of the blend membrane was in accordance with the proportion of sponge-like structure. These behaviours were attributed to the different roles of Polyvinylpyrrolidone in the dopes and ethanol in the coagulants, respectively. Polyvinylidene fluoride

Modified bathroom scale and balance assessment: a comparison with clinical tests

OpenAIRE

Duch?ne, Jacques; Hewson, David; Rumeau, Pierre

2016-01-01

Frailty and detection of fall risk are major issues in preventive gerontology. A simple tool frequently used in daily life, a bathroom scale (balance quality tester: BQT), was modified to obtain information on the balance of 84 outpatients consulting at a geriatric clinic. The results computed from the BQT were compared to the values of three geriatric tests that are widely used either to detect a fall risk or frailty (timed get up and go: TUG; 10?m walking speed: WS; walking time: WT; one-le...

Quickly Screening for Potential α-Glucosidase Inhibitors from Guava Leaves Tea by Bioaffinity Ultrafiltration Coupled with HPLC-ESI-TOF/MS Method.

Science.gov (United States)

Wang, Lu; Liu, Yufeng; Luo, You; Huang, Kuiying; Wu, Zhenqiang

2018-02-14

Guava leaves tea (GLT) has a potential antihyperglycemic effect. Nevertheless, it is unclear which compound plays a key role in reducing blood sugar. In this study, GLT extract (IC 50 = 19.37 ± 0.21 μg/mL) exhibited a stronger inhibitory potency against α-glucosidase than did acarbose (positive control) at IC 50 = 178.52 ± 1.37 μg/mL. To rapidly identify the specific α-glucosidase inhibitor components from GLT, an approach based on bioaffinity ultrafiltration combined with high performance liquid chromatography coupled to electrospray ionization-time-of-flight-mass spectrometry (BAUF-HPLC-ESI-TOF/MS) was developed. Under the optimal bioaffinity ultrafiltration conditions, 11 corresponding potential α-glucosidase inhibitors with high affinity degrees (ADs) were screened and identified from the GLT extract. Quercetin (IC 50 = 4.51 ± 0.71 μg/mL) and procyanidin B3 (IC 50 = 28.67 ± 5.81 μg/mL) were determined to be primarily responsible for the antihyperglycemic effect, which further verified the established screening method. Moreover, structure-activity relationships were discussed. In conclusion, the BAUF-HPLC-ESI-TOF/MS method could be applied to determine the potential α-glucosidase inhibitors from complex natural products quickly.

Safety of a new, ultrafiltrated whey hydrolysate formula in children with cow milk allergy

DEFF Research Database (Denmark)

Halken, S; Høst, A; Hansen, L G

1993-01-01

The purpose of this study was to determine whether a new ultrafiltrated whey hydrolysate infant formula, Profylac, could be administered safely to children with cow milk protein allergy/intolerance. Profylac has a stated molecular weight of ... which is controlled by a combination of ELISA-techniques and immunochemical methods. The study comprised 66 children with cow milk protein allergy/intolerance diagnosed by controlled elimination/challenge procedures. The children were aged 1 month-14.5 years, median 1 11/12 years and 15 were below 1...... year. Thirty-five of these children had proven IgE-mediated reactions (cow milk protein allergy). Sixty-one of the children had at least two different symptoms and 31 had concomitant allergies to other foods and/or inhalants. All 66 children underwent and tolerated open, controlled challenges...

Organic fouling behavior of superhydrophilic polyvinylidene fluoride (PVDF) ultrafiltration membranes functionalized with surface-tailored nanoparticles: Implications for organic fouling in membrane bioreactors

KAUST Repository

Liang, Shuai

2014-08-01

This study systematically investigates the organic fouling behavior of a superhydrophilic polyvinylidene fluoride (PVDF) ultrafiltration membrane functionalized via post-fabrication tethering of surface-tailored silica nanoparticles to poly(methacrylic acid)-grafted PVDF membrane surface. Sodium alginate (SA), Suwannee River natural organic matter (SRNOM), and bovine serum albumin (BSA) were used as model organic foulants to investigate the antifouling behavior of the superhydrophilic membrane with combined-fouling (mixture of foulants) and individual-fouling (single foulant) tests. A membrane bioreactor (MBR) plant supernatant was also used to verify the organic antifouling property of the superhydrophilic membrane under realistic conditions. Foulant size distributions and foulant-membrane interfacial forces were measured to interpret the observed membrane fouling behavior. Molecular weight cutoff measurements confirmed that membrane functionalization did not adversely affect the intrinsic membrane selectivity. Both filtration tests with the synthetic foulant-mixture solution (containing SA, SRNOM, and BSA) and MBR plant supernatant demonstrated the reliability and durability of the antifouling property of the superhydrophilic membrane. The conspicuous reduction in foulant-membrane interfacial forces for the functionalized membrane further verified the antifouling properties of the superhydrophilic membrane, suggesting great potential for applications in wastewater treatment. © 2014 Elsevier B.V.

Smelling themselves: Dogs investigate their own odours longer when modified in an "olfactory mirror" test.

Science.gov (United States)

Horowitz, Alexandra

2017-10-01

While domestic dogs, Canis familiaris, have been found to be skillful at social cognitive tasks and even some meta-cognitive tasks, they have not passed the test of mirror self-recognition (MSR). Acknowledging the motivational and sensory challenges that might hinder performance, even before the question of self-recognition is broached, this study creates and enacts a novel design extrapolated from the species' natural behaviour. Given dogs' use of olfactory signals in communication, this experiment presents dogs with various canisters for approach and investigation. Each holds an odorous stimulus: in the critical test, either an "olfactory mirror" of the subject - the dog's own urine - or one in which the odour stimulus is modified. By looking at subjects' investigation times of each canister, it is shown that dogs distinguish between the olfactory "image" of themselves when modified: investigating their own odour for longer when it had an additional odour accompanying it than when it did not. Such behaviour implies a recognition of the odour as being of or from "themselves." The ecological validity of this odour presentation is examined by presenting to the subjects odours of other known or unknown dogs: dogs spend longer investigating the odour of other dogs than their own odour. Finally, in a second experiment, subjects spent longer with the modified stimulus than with the modified odour by itself, indicating that novelty alone does not explain the dogs' behavior. This study translates the MSR study for a species whose primary sensory modality is olfaction, and finds both that natural sniffing behaviour can be replicated in the lab and that dogs show more investigative interest in their own odours when modified. Copyright © 2017 Elsevier B.V. All rights reserved.

The ability of modified star excursion balance test to differentiate between women athletes with and without chronic ankle instability

Directory of Open Access Journals (Sweden)

Asma Razeghi

2016-05-01

Full Text Available The Star Excursion Balance Test (SEBT is one functional clinical test that widely used to assess dynamic balance in patients with ankle injuries. Since the ability of this test to detect impairments between athletes with and without chronic ankle instability(CAI is not clear, the aim of present study was to determine if the modified SEBT could detect reach deficits in patients with unilateral CAI. A convenience sample of thirty elite and sub elite women athletes were selected and assigned into two groups: CAI group (Mean ± SD: age: 25±3.5 years; height: 1.68±0.09 m; weight: 62.7±7.3kg, and healthy controls (Mean ± SD: age: 26±4.2 years; height: 1.69±0.05 m; weigh t: 62.7±7.3 kg.The dynamic balance test was obtained using modified SEBT from both limbs of each participant. The independent sample t-test was used for both between group and within group inter-limb comparisons. There was no significant difference in any directions of modified SEBT between two groups in both limbs. No significant interlimb differences were also observed within both groups. The modified SEBT may not enough sensitive to differentiate between athletes with and without CAI. Other factors such as ankle range of motion, muscle strength and pain intensity should be considered for better interpretation of the SEBT results.

[Evaluation of fetal lung maturity using a modified lecithin-sphingomyelin determination and Clements' foam test].

Science.gov (United States)

Neumann, G; Gartzke, J; Faber, G

1978-01-01

The modified thin layer chromatographic method for the determination of the phospholipids lecithin and sphingomyelin from amniotic fluid is useful in estimating fetal pulmonary maturity. The foam test of Clements is a simple rapid method for screening of suspicious cases of pregnancies at risk and of great value as bed side test even performing by the doctor. In comparing Clements-Test with thin layer chromatographic for L/S-Ratio determination we found a good correlation of 81,8% of all cases.

THE EFFECT OF THE TYPE OF ADMIXTURE ON THE PROPERTIES OF POLYACRYLONITRILE MEMBRANES MODIFIED WITH NANOTUBES, GRAPHENE OXIDE AND GRAPHENE

Directory of Open Access Journals (Sweden)

Beata Fryczkowska

2017-09-01

Full Text Available This paper presents the results of research on the production of composite polyacrylonitrile (PAN membranes with nanotubes (MWCNT, graphene (RG and graphene oxide (GO addition. All of the specified additions differ diametrically in terms of properties, starting from the spatial structure of the particles, up to the chemical properties. Membranes were obtained using phase inversion method from a solution of N,N-dimethylformamide (DMF. Subsequently, the impact of the nano-addition on the transport and separation properties of the membranes were investigated using Millipore AMICON ultrafiltration kit. Membranes with graphene addition (PAN/RG are characterized by the best transport properties and the highest specific permeate flux values in the range of ~913÷1006 [dm3/m2×h] for working pressure of 2.0 MPa. To test the separation properties, electroplating waste water generated in one of the Silesian galvanizing plants was used. The qualitative and quantitative composition of the waste water was tested by UV-Vis spectrophotometer (HACH and absorption atomic spectrometry (AAS. The ultrafiltration process carried out on composite membranes allows for the complete removal of phosphate ions and ~88÷94% of iron from the waste water. The rejection coefficient of the remaining metals is high: ~ 35 ÷ 85% for copper and ~ 17 ÷ 100% for cadmium.

Polysulfone hemodiafiltration membranes with enhanced anti-fouling and hemocompatibility modified by poly(vinyl pyrrolidone) via in situ cross-linked polymerization

Energy Technology Data Exchange (ETDEWEB)

Zhu, Lijing, E-mail: zhulijing@nimte.ac.cn; Song, Haiming; Wang, Jiarong; Xue, Lixin, E-mail: xuelx@nimte.ac.cn

2017-05-01

Poly(vinyl pyrrolidone) (PVP) and its copolymers have been widely employed for the modification of hemodiafiltration membranes due to their excellent hydrophilicity, antifouling and hemocompatibility. However, challenges still remain to simplify the modification procedure and to improve the utilization efficiency. In this paper, antifouling and hemocompatibility polysulfone (PSf) hemodiafiltration membranes were fabricated via in situ cross-linked polymerization of vinyl pyrrolidone (VP) and vinyltriethoxysilane (VTEOS) in PSf solutions and non-solvent induced phase separation (NIPS) technique. The prepared membranes were characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM), which suggested that VP and VTEOS have been cross-linked copolymerized in PSf membranes. The modified PSf membranes with high polymer content showed improved hydrophilicity, ultrafiltration and protein antifouling ability. In addition, the modified PSf membranes showed lower protein adsorption, inhibited platelet adhesion and deformation, prolonged the activated partial thromboplastin time (APTT), prothrombin time (PT), and decreased the content of fibrinogen (FIB) transferring to fibrin, indicating enhanced hemocompatibility. In a word, the present work provides a simple and effective one-step modification method to construct PSf membranes with improved hydrophilicity, antifouling and hemocompatibility. - Highlights: • PSf membranes were modified by in situ cross-linked polymerization. • The modified PSf membranes showed enhanced hydrophilicity. • The anti-fouling and hemocompatibility of PSf membranes were improved.

Polysulfone hemodiafiltration membranes with enhanced anti-fouling and hemocompatibility modified by poly(vinyl pyrrolidone) via in situ cross-linked polymerization

International Nuclear Information System (INIS)

Zhu, Lijing; Song, Haiming; Wang, Jiarong; Xue, Lixin

2017-01-01

Poly(vinyl pyrrolidone) (PVP) and its copolymers have been widely employed for the modification of hemodiafiltration membranes due to their excellent hydrophilicity, antifouling and hemocompatibility. However, challenges still remain to simplify the modification procedure and to improve the utilization efficiency. In this paper, antifouling and hemocompatibility polysulfone (PSf) hemodiafiltration membranes were fabricated via in situ cross-linked polymerization of vinyl pyrrolidone (VP) and vinyltriethoxysilane (VTEOS) in PSf solutions and non-solvent induced phase separation (NIPS) technique. The prepared membranes were characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM), which suggested that VP and VTEOS have been cross-linked copolymerized in PSf membranes. The modified PSf membranes with high polymer content showed improved hydrophilicity, ultrafiltration and protein antifouling ability. In addition, the modified PSf membranes showed lower protein adsorption, inhibited platelet adhesion and deformation, prolonged the activated partial thromboplastin time (APTT), prothrombin time (PT), and decreased the content of fibrinogen (FIB) transferring to fibrin, indicating enhanced hemocompatibility. In a word, the present work provides a simple and effective one-step modification method to construct PSf membranes with improved hydrophilicity, antifouling and hemocompatibility. - Highlights: • PSf membranes were modified by in situ cross-linked polymerization. • The modified PSf membranes showed enhanced hydrophilicity. • The anti-fouling and hemocompatibility of PSf membranes were improved.

Non-parametric Tuning of PID Controllers A Modified Relay-Feedback-Test Approach

CERN Document Server

Boiko, Igor

2013-01-01

The relay feedback test (RFT) has become a popular and efficient  tool used in process identification and automatic controller tuning. Non-parametric Tuning of PID Controllers couples new modifications of classical RFT with application-specific optimal tuning rules to form a non-parametric method of test-and-tuning. Test and tuning are coordinated through a set of common parameters so that a PID controller can obtain the desired gain or phase margins in a system exactly, even with unknown process dynamics. The concept of process-specific optimal tuning rules in the nonparametric setup, with corresponding tuning rules for flow, level pressure, and temperature control loops is presented in the text.   Common problems of tuning accuracy based on parametric and non-parametric approaches are addressed. In addition, the text treats the parametric approach to tuning based on the modified RFT approach and the exact model of oscillations in the system under test using the locus of a perturbedrelay system (LPRS) meth...

Development of the Modified Four Square Step Test and its reliability and validity in people with stroke.

Science.gov (United States)

Roos, Margaret A; Reisman, Darcy S; Hicks, Gregory; Rose, William; Rudolph, Katherine S

2016-01-01

Adults with stroke have difficulty avoiding obstacles when walking, especially when a time constraint is imposed. The Four Square Step Test (FSST) evaluates dynamic balance by requiring individuals to step over canes in multiple directions while being timed, but many people with stroke are unable to complete it. The purposes of this study were to (1) modify the FSST by replacing the canes with tape so that more persons with stroke could successfully complete the test and (2) examine the reliability and validity of the modified version. Fifty-five subjects completed the Modified FSST (mFSST) by stepping over tape in all four directions while being timed. The mFSST resulted in significantly greater numbers of subjects completing the test than the FSST (39/55 [71%] and 33/55 [60%], respectively) (p < 0.04). The test-retest, intrarater, and interrater reliability of the mFSST were excellent (intraclass correlation coefficient ranges: 0.81-0.99). Construct and concurrent validity of the mFSST were also established. The minimal detectable change was 6.73 s. The mFSST, an ideal measure of dynamic balance, can identify progress in people with stroke in varied settings and can be completed by a wide range of people with stroke in approximately 5 min with the use of minimal equipment (tape, stop watch).

NEUROMUSCULAR FATIGUE DURING A MODIFIED BIERING-SØRENSEN TEST IN SUBJECTS WITH AND WITHOUT LOW BACK PAIN

Directory of Open Access Journals (Sweden)

Mark J. Pitcher

2007-12-01

Full Text Available Studies employing modified Biering-Sørenson tests have reported that low back endurance is related to the potential for developing low back pain. Understanding the manner in which spinal musculature fatigues in people with and without LBP is necessary to gain insight into the sensitivity of the modified Biering-Sørenson test to differentiate back health. Twenty male volunteers were divided into a LBP group of subjects with current subacute or a history of LBP that limited their activity (n = 10 and a control group (n = 10. The median frequency of the fast Fourier transform was calculated from bilateral surface electromyography (EMG of the upper lumbar erector spinae (ULES, lower lumbar erector spinae (LLES and biceps femoris while maintaining a prescribed modified Biering-Sørensen test position and exerting isometric forces equivalent to 100, 120, 140 and 160% of the estimated mass of the head-arms-trunk (HAT segment. Time to failure was also investigated across the percentages of HAT. Fatigue time decreased with increasing load and differences between groups increased as load increased, however these differences were not significant. Significant differences in the EMG median frequency between groups occurred in the right biceps femoris (p < 0.05 with significant pairwise differences occurring at 140% for the left biceps femoris and at 160% for the right biceps femoris. There were significant pairwise differences at 120% for average EMG of the right biceps femoris and at 140% for the right ULES, and right and left biceps femoris (p < 0.05. The modified Biering-Sørensen test as usually performed at 100% HAT is not sufficient to demonstrate significant differences between controls and subjects with varying degrees of mild back disability based on the Oswestry classification

Bacterial challenge of NISSHO ultrafilter ETF 609: results of in vitro testing.

Science.gov (United States)

Krautzig, S; Lonnemann, G; Shaldon, S; Koch, K M

1996-07-01

In hemodialysis, a certain degree of bacterial contamination on the dialysate side is a regular finding. Concern has been growing that this contamination may lead to a chronic inflammatory response in the patient. Ultrafiltration of dialysate can be used to reduce bacterial content and levels of cytokine-inducing substances upstream of the patient's dialyzer. The aim of this study was to test in vitro the rejection capacity of a polysulfone hollow-fiber ultrafilter (ETF 609, NISSHO Co., Osaka, Japan) challenged with bacterial filtrates derived from Pseudomonas aeruginosa PA103. Results showed a reduction of interleukin-1 beta-inducing activity (measured on peripheral blood mononuclear cells) from 5,035 +/- 394 pg/ml prefilter to nondetectable levels postfilter and endotoxin levels (limulus amebocyte lysate assay) of 4,167 +/- 1,079 versus 12 +/- 2 pg/ml, respectively. In conclusion, ultrafiltration of dialysate with the polysulfone ultrafilter ETF 609 leads to a potent reduction of cytokine-inducing activity.

Proposal for a Test Protocol for Genetically Modified Plants

DEFF Research Database (Denmark)

Strandberg, B.; Kjær, C.

1999-01-01

The report contains the proceedings from the conference Genetically Modified Organisms in Nordic Habitats - Sustainable Use or Loss of Diversity? in Helsinki, 1998......The report contains the proceedings from the conference Genetically Modified Organisms in Nordic Habitats - Sustainable Use or Loss of Diversity? in Helsinki, 1998...

Contribution of effluent organic matter (EfOM) to ultrafiltration (UF) membrane fouling: Isolation, characterization, and fouling effect of EfOM fractions

KAUST Repository

Zheng, Xing

2014-11-01

EfOM has been regarded as a major organic foulant resulting in UF membrane fouling in wastewater reclamation. To investigate fouling potential of different EfOM fractions, the present study isolated EfOM into hydrophobic neutrals (HPO-N), colloids, hydrophobic acids (HPO-A), transphilic neutrals and acids (TPI), and hydrophilics (HPI), and tested their fouling effect in both salt solution and pure water during ultrafiltration (UF). Major functional groups and chemical structure of the isolates were identified using Fourier transform infrared spectroscopy (FT-IR) and solid-state carbon nuclear magnetic resonance (13C NMR) analysis. The influence of the isolation process on the properties of EfOM fractions was minor because the raw and reconstituted secondary effluents were found similar with respect to UV absorbance, molecular size distribution, and fluorescence character. In membrane filtration tests, unified membrane fouling index (UMFI) and hydraulic resistance were used to quantify irreversible fouling potential of different water samples. Results show that under similar DOC level in feed water, colloids present much more irreversible fouling than other fractions. The fouling effect of the isolates is related to their size, chemical properties, and solution chemistry. Further investigations have identified that the interaction between colloids and other fractions also influences the performance of colloids in fouling phenomena. © 2014 Elsevier Ltd.

Who Discovered America? How Many Seeds in a Watermelon? Tips for Modifying Teacher-Made Tests.

Science.gov (United States)

Watanabe, Addison; Algozzine, Bob

1989-01-01

This article discusses ways teachers may vary and modify teacher-made tests to better facilitate prescriptive programing for special education students. Formats featuring statements, object identification, gestures, and writing are discussed, as are item alterations in terms of both item presentation and student responses. (PB)

Low amplitude impact of PBX 9501: Modified Steven spigot gun tests

Energy Technology Data Exchange (ETDEWEB)

Idar, D.J.; Lucht, R.A.; Straight, J.W. [and others

1998-12-01

Low-velocity mechanical impact and subsequent high explosive (HE) reaction are of concern in credible accident scenarios involving the handling, transport, and storage of nuclear weapons. Using modified Steven spigot gun tests, the authors have investigated the high-explosive violent-reaction (HEVR) potential of PBX 9501 to low-amplitude insult. Reliable modeling predictions require that one identify the relevant parameters and behavioral responses that are key to the reaction mechanism(s) in PBX 9501. Additional efforts have been targeted at identifying relevant differences in the response between baseline and stockpile-aged PBX 9501 to low-velocity impacts.

Evaluation of ultrafiltration membranes for treating low-level radioactive contaminated liquid waste

International Nuclear Information System (INIS)

Koenst, J.W.; Roberts, R.C.

1978-01-01

A series of experiments were performed on Waste Disposal Facility (WD) influent using Romicon hollow fiber ultrafiltration modules with molecular weight cutoffs ranging from 2000 to 80,000. The rejection of conductivity was low in most cases. The rejection of radioactivity ranged from 90 to 98%, depending on the membrane type and on the feed concentration. Typical product activity ranged from 7 to 100 dis/min/ml of alpha radiation. Experiments were also performed on alpha-contaminated laundry wastewater. Results ranged from 98 to >99.8%, depending on the membrane type. This yielded a product concentration of less than 0.1 dis/min/ml of alpha radiation. Tests on PP-Building decontamination water yielded rejections of 85 to 88% alpha radiation depending on the membrane type. These experiments show that the ability to remove radioactivity by membrane is a function of the contents of the waste stream because the radioactivity in the wastewater is in various forms: ionic, polymeric, colloidal, and absorbed onto suspended solids. Although removal of suspended or colloidal material is very high, removal of ionic material is not as effective. Alpha-contaminated laundry wastewater proved to be the easiest to decontaminate, whereas the low-level PP-Building decontamination water proved to be the most difficult to decontaminate. Decontamination of the WD influent, a combined waste stream, varied considerably from day to day because of its constantly changing makeup. The WD influent was also treated with various substances, such as polyelectrolytes, complexing agents, and coagulants, to determine if these additives would aid in the removal of radioactive material from the various wastewaters by complexing the ionic species. At the present time, none of the additives evaluated has had much effect; but experiments are continuing

Pre-treatment and membrane ultrafiltration using treated palm oil mill effluent (POME

Directory of Open Access Journals (Sweden)

Wong Pui Wah

2002-11-01

Full Text Available Treatment of palm oil mill effluent (POME has always been a topic of research in Malaysia. This effluent that is extremely rich in organic content needs to be properly treated to minimize environmental hazards before it is released into watercourses. The common practice for treating POME in Malaysia involves a combination of aerobic and anaerobic methods. The purpose of tertiary treatment is to allow the treated water to be reused in the mill operations for other purposes such as feed water. The proposed treatment will also ensure the industry to meet a more stringent discharge standard in terms of the BOD, COD and nitrogen values. In this study membrane ultrafiltration is used as the tertiary treatment method. Before the actual membrane operation was conducted, the samples were pre-treated using three separate method namely filtration, centrifugation and coagulation. It was found that the combination of filtrationultrafiltration treatment POME produced the best-treated sample quality in terms of pollutant contents elimination, namely % BOD, % COD and % nitrogen removal.

EMPIRICAL TESTING OF MODIFIED BLACK-SCHOLES OPTION PRICING MODEL FORMULA ON NSE DERIVATIVE MARKET IN INDIA

Directory of Open Access Journals (Sweden)

Ambrish Gupta

2013-01-01

Full Text Available The main objectives of this paper are to incorporate modification in Black-Scholes option pricing model formula by adding some new variables on the basis of given assumption related to risk-free interest rate, and also shows the calculation process of new risk-free interest rate on the basis of modified variable. This paper also identifies the various situations in empirical testing of modified and original Black-Scholes formula with respect to the market value on the basis of assumed and calculated risk-free interest rate.

WTP Pilot-Scale Evaporation Tests

International Nuclear Information System (INIS)

QURESHI, ZAFAR

2004-01-01

This report documents the design, assembly, and operation of a Pilot-Scale Evaporator built and operated by SRTC in support of Waste Treatment Plant (WTP) Project at the DOE's Hanford Site. The WTP employs three identical evaporators, two for the Waste Feed and one for the Treated LAW. The Pilot-Scale Evaporator was designed to test simulants for both of these waste streams. The Pilot-Scale Evaporator is 1/76th scale in terms of evaporation rates. The basic configuration of forced circulation vacuum evaporator was employed. A detailed scaling analysis was performed to preserve key operating parameters such as basic loop configuration, system vacuum, boiling temperature, recirculation rates, vertical distances between important hardware pieces, reboiler heat transfer characteristics, vapor flux, configuration of demisters and water spray rings. Three evaporation test campaigns were completed. The first evaporation run used water in order to shake down the system. The water runs were important in identifying a design flaw that inhibited mixing in the evaporator vessel, thus resulting in unstable boiling operation. As a result the loop configuration was modified and the remaining runs were completed successfully. Two simulant runs followed the water runs. Test 1: Simulated Ultrafiltration Recycles with HLW SBS, and Test 2: Treated AN102 with Envelop C LAW. Several liquid and offgas samples were drawn from the evaporator facility for regulatory and non-regulatory analyses. During Test 2, the feed and the concentrate were spiked with organics to determine organic partitioning. The decontamination factor (DF) for Test 1 was measured to be 110,000 (more than the expected value of 100,000). Dow Corning Q2-3183A antifoam agent was tested during both Tests 1 and 2. It was determined that 500 ppm of this antifoam agent was sufficient to control the foaminess to less than 5 per cent of the liquid height. The long-term testing (around 100 hours of operation) did not show any

Applying polarity rapid assessment method and ultrafiltration to characterize NDMA precursors in wastewater effluents.

Science.gov (United States)

Chen, Chao; Leavey, Shannon; Krasner, Stuart W; Mel Suffet, I H

2014-06-15

Certain nitrosamines in water are disinfection byproducts that are probable human carcinogens. Nitrosamines have diverse and complex precursors that include effluent organic matter, some anthropogenic chemicals, and natural (likely non-humic) substances. An easy and selective tool was first developed to characterize nitrosamine precursors in treated wastewaters, including different process effluents. This tool takes advantages of the polarity rapid assessment method (PRAM) and ultrafiltration (UF) (molecular weight distribution) to locate the fractions with the strongest contributions to the nitrosamine precursor pool in the effluent organic matter. Strong cation exchange (SCX) and C18 solid-phase extraction cartridges were used for their high selectivity for nitrosamine precursors. The details of PRAM operation, such as cartridge clean-up, capacity, pH influence, and quality control were included in this paper, as well as the main parameters of UF operation. Preliminary testing of the PRAM/UF method with effluents from one wastewater treatment plant gave very informative results. SCX retained 45-90% of the N-nitrosodimethylamine (NDMA) formation potential (FP)-a measure of the precursors-in secondary and tertiary wastewater effluents. These results are consistent with NDMA precursors likely having a positively charged amine group. C18 adsorbed 30-45% of the NDMAFP, which indicates that a substantial portion of these precursors were non-polar. The small molecular weight (MW) (10 kDa) fractions obtained from UF were the primary contributors to NDMAFP. The combination of PRAM and UF brings important information on the characteristics of nitrosamine precursors in water with easy operation. Copyright © 2014 Elsevier Ltd. All rights reserved.

A STUDY OF BRACKISH WATER MEMBRANE WITH ULTRAFILTRATION PRETREATMENT IN INDONESIA´S COASTAL AREA

Directory of Open Access Journals (Sweden)

Elis Hastuti

2012-01-01

Full Text Available Water pollution and sea water intrusion to water sources in coastal areas result lack of provision safe drinking water by the drinking water regional company or coastal community. The existing water treatment plant that operated on brackish surface water or groundwater feed requires improving process. Membrane process could be a choice to treat the quality of brackish water to the level of potable water that designed to lower cost with high stabil flux and longer lifetime. This research focus on application of pilot plant of brackish water treatment using Ultrafiltration (UF membrane-air lift system as pretreatment of Reverse Osmosis (RO membrane-low pressure. Brackish water sources contain high colloidal and suspended solids that can cause fouling load of RO membranes and impair its performance. UF pretreatment operation tested by addition of compressed air into the feed (air lift system, resulted stable flux, reduces membrane fouling and low feed pressure. A flux of RO with UF pretreatment can produce drinking water of 30--61 L/m2·hour. It was observed, the good quality of RO permeate resulted by using a pretreatment of UF--PS (Polysulfone-UF with total dissolved solid rejection about 96--98% and color rejection about 99--100% at 5 or 8 bars of operation pressure. This paper concludes that performance of membrane technology with UF--air lift system pretreatment and RO membrane-low pressure could be accepted as condition of brackish water source in Indonesia coastal areas in producing drinking water.

A study of brackish water membrane with ultrafiltration pretreatment in Indonesia’s coastal area

Directory of Open Access Journals (Sweden)

Elis Hastuti

2012-06-01

Full Text Available Water pollution and sea water intrusion to water sources in coastal areas result lack of provision safe drinking water by the drinking water regional company or coastal community. The existing water treatment plant that operated on brackish surface water or groundwater feed requires improving process. Membrane process could be a choice to treat the quality of brackish water to the level of potable water that designed to lower cost with high stabil flux and longer lifetime. This research focus on application of pilot plant of brackish water treatment using Ultrafiltration (UF membrane-air lift system as pretreatment of Reverse Osmosis (RO membrane-low pressure. Brackish water sources contain high colloidal and suspended solids that can cause fouling load of RO membranes and impair its performance. UF pretreatment operation tested by addition of compressed air into the feed (air lift system, resulted stable flux, reduces membrane fouling and low feed pressure. A flux of RO with UF pretreatment can produce drinking water of 30–61 L/m2∙hour. It was observed, the good quality of RO permeate resulted by using a pretreatment of UF–PS (Polysulfone-UF with total dissolved solid rejection about 96–98% and color rejection about 99–100% at 5 or 8 bars of operation pressure. This paper concludes that performance of membrane technology with UF–air lift system pretreatment and RO membrane-low pressure could be accepted as condition of brackish water source in Indonesia coastal areas in producing drinking water.

Removal of paraquat and linuron from water by continuous flow adsorption/ ultrafiltration membrane processes

International Nuclear Information System (INIS)

Zahoor, M.

2013-01-01

The magnetic activated carbon (MAC) was prepared, characterized and compared with powdered activated carbon (PAC) for its adsorptive parameters. Both adsorbents were then used in combination ultrafiltration (UF) membrane as pretreatment for the removal of paraquat and linuron from water. The comparison of membrane parameters like percent retention, permeate flux and backwash times for PAC/UF and MAC/UF hybrid processes showed that percent retention of paraquat and linuron was high for PAC due to its high surface area. However due to cake formation over membrane surface the decline permeate fluxes and long backwash times for PAC were observed. PAC also caused blackening of pipes and flow meter. MAC (an iron oxide and PAC composite) was removed from slurry through magnet thus no cake formation and secondary problems observed for PAC was not encountered. Also the backwash times were minimum for MAC/UF process. (author)

Effect of membrane properties on the performance of a hybrid GAC and ultrafiltration process for water treatment.

Science.gov (United States)

Qiao, Tiejun; Wu, Guangxue; Zhang, Xihui; Au, Doris W T; Zhang, Jinsong

2012-06-01

The performance of a hybrid granular activated carbon (GAC) and ultrafiltration (UF) process for water treatment was investigated using five types of UF membranes. The removal percentages for chemical oxygen demand (COD(Mn)), particles (> or = 2 microm) and total bacteria by the hybrid process were 30-40%, 98-99% and 76-92%, respectively. No invertebrates were detected in the hybrid process effluent. Transmembrane pressure and specific permeate flux (SPF) of the five types of membranes varied. With decreasing membrane pore sizes, removal of COD(Mn) and particles increased, whereas SPF firstly decreased and then increased. Hydrophilic membranes had a relatively high COD(Mn) removal potential, but did not obviously affect particle removal or SPF.

A modified Lorentz theory as a test theory of special relativity

Science.gov (United States)

Chang, T.; Torr, D. G.; Gagnon, D. R.

1988-01-01

Attention has been given recently to a modified Lorentz theory (MLT) that is based on the generalized Galilean transformation. Some explicit formulas within the framework of MLT, dealing with the one-way velocity of light, slow-clock transport, and the Doppler effect are derived. A number of typical experiments are analyzed on this basis. Results indicate that the empirical equivalence between MLT and special relativity is still maintained to second order terms. The results of previous works that predict that the MLT might be distinguished from special relativity at the third order by Doppler centrifuge tests capable of a fractional frequency detection threshold of 10 to the -15th are confirmed.

Membrane Bioreactor (MBR) as Alternative to a Conventional Activated Sludge System Followed by Ultrafiltration (CAS-UF) for the Treatment of Fischer-Tropsch Reaction Water from Gas-to-Liquids Industries

NARCIS (Netherlands)

Laurinonyte, Judita; Meulepas, Roel J.W.; Brink, van den Paula; Temmink, Hardy

2017-01-01

The potential of a membrane bioreactor (MBR) system to treat Fischer-Tropsch (FT) reaction water from gas-to-liquids (GTL) industries was investigated and compared with the current treatment system: a conventional activated sludge system followed by an ultrafiltration (CAS-UF) unit. The MBR and

Challenges in testing genetically modified crops for potential increases in endogenous allergen expression for safety.

Science.gov (United States)

Panda, R; Ariyarathna, H; Amnuaycheewa, P; Tetteh, A; Pramod, S N; Taylor, S L; Ballmer-Weber, B K; Goodman, R E

2013-02-01

Premarket, genetically modified (GM) plants are assessed for potential risks of food allergy. The major risk would be transfer of a gene encoding an allergen or protein nearly identical to an allergen into a different food source, which can be assessed by specific serum testing. The potential that a newly expressed protein might become an allergen is evaluated based on resistance to digestion in pepsin and abundance in food fractions. If the modified plant is a common allergenic source (e.g. soybean), regulatory guidelines suggest testing for increases in the expression of endogenous allergens. Some regulators request evaluating endogenous allergens for rarely allergenic plants (e.g. maize and rice). Since allergic individuals must avoid foods containing their allergen (e.g. peanut, soybean, maize, or rice), the relevance of the tests is unclear. Furthermore, no acceptance criteria are established and little is known about the natural variation in allergen concentrations in these crops. Our results demonstrate a 15-fold difference in the major maize allergen, lipid transfer protein between nine varieties, and complex variation in IgE binding to various soybean varieties. We question the value of evaluating endogenous allergens in GM plants unless the intent of the modification was production of a hypoallergenic crop. © 2012 John Wiley & Sons A/S.

Detection of antibodies to transmissible gastroenteritis virus of swine by modified autoradiographic test

Energy Technology Data Exchange (ETDEWEB)

Stepanek, J; Hampl, J; Franz, J; Mensik, P; Skrobak, F [Vyzkumny Ustav Veterinarniho Lekarstvi, Brno-Medlanky (Czechoslovakia)

1982-08-01

A modified method of autoradiographic determination of virus antibodies of gastroenteritis of swine was developed. It is based on the actual reaction between antigen bound in cells of the infected cell cultures and antibodies in tested sera, which is visualized by rabbit antibodies labelled with /sup 125/I (/sup 125/I RaSw IgG antibody) to porcine IgG, on a sensitive radiograph and evaluated by darkening at the point of positive immunological reaction. Specificity of the test and mutual comparability and reproducibility of the results were confirmed by examining the known positive and negative sera and by a comparison with the results of the virus-neutralization test. Of the 36 examined porcine blood sera, antibodies were only proved autoradiographically in the samples positive also by virus-neutralization. In experimentally infected pigs, the same dynamics of antibody production was recorded by the two tests. They were, however, demonstrated autoradiographically the eighth day after infection, while by virus neutralization test as late as 14th day. Their level increased gradually till 35th day after infection.

Process Testing Results and Scaling for the Hanford Waste Treatment and Immobilization Plant (WTP) Pretreatment Engineering Platform - 10173

International Nuclear Information System (INIS)

Kurath, Dean E.; Daniel, Richard C.; Baldwin, David L.; Rapko, Brian M.; Barnes, Steven M.; Gilbert, Robert A.; Mahoney, Lenna A.; Huckaby, James L.

2010-01-01

The U.S. Department of Energy-Office of River Protections Hanford Tank Waste Treatment and Immobilization Plant (WTP) is being designed and built to pretreat and then vitrify a large portion of the wastes in Hanfords 177 underground waste storage tanks at Richland, Washington. In support of this effort, engineering-scale tests at the Pretreatment Engineering Platform (PEP) have been completed to confirm the process design and provide improved projections of system capacity. The PEP is a 1/4.5-scale facility designed, constructed, and operated to test the integrated leaching and ultrafiltration processes being deployed at the WTP. The PEP replicates the WTP leaching processes with prototypic equipment and control strategies and non-prototypic ancillary equipment to support the core processing. The testing approach used a nonradioactive aqueous slurry simulant to demonstrate the unit operations of caustic and oxidative leaching, cross-flow ultrafiltration solids concentration, and solids washing. Parallel tests conducted at the laboratory scale with identical simulants provided results that allow scale-up factors to be developed between the laboratory and PEP performance. This paper presents the scale-up factors determined between the laboratory and engineering-scale results and presents arguments that extend these results to the full-scale process.

Enhanced antimony(V) removal using synergistic effects of Fe hydrolytic flocs and ultrafiltration membrane with sludge discharge evaluation.

Science.gov (United States)

Ma, Baiwen; Wang, Xing; Liu, Ruiping; Qi, Zenglu; Jefferson, William A; Lan, Huachun; Liu, Huijuan; Qu, Jiuhui

2017-09-15

The integration of adsorbents with ultrafiltration (UF) membranes is a promising method for alleviating membrane fouling and reducing land use. However, a number of problems have become apparent concerning the granular adsorbents used currently, such as high running cost, high chance of causing membrane surface damage, low in situ chemical cleaning efficiency, etc. Herein, to overcome these disadvantages, loose in situ hydrolyzed flocs were directly injected into the membrane tank, providing strong adsorption ability at low cost. To test the feasibility of this method, the heavy metal pollutant antimony (Sb (V)) in a water plant was chosen at a test case, which is similar to arsenic and difficult to remove. We found that Fe-based flocs integrated with an UF membrane showed a large potential advantage in removing Sb(V), even after running for 110 days. We demonstrated that the observed slow transmembrane pressure development could be ascribed to the loose floc cake layer formed, even though some extracellular polymeric substances were induced during operation. We also found that the floc cake layer was easily removed by washing with feed water or dissolved by in situ chemical cleaning under strongly acidic conditions, and many primary membrane pores were clearly observed. In addition, a relative long sludge discharge interval was feasible for this technology and the effluent quality was good, including the turbidity, chromaticity and iron concentration. Based on the excellent performance, these flocs integrated with UF membranes indeed show potential for application in water treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ultra faint dwarf galaxies: an arena for testing dark matter versus modified gravity

Energy Technology Data Exchange (ETDEWEB)

Lin, Weikang; Ishak, Mustapha, E-mail: wxl123830@utdallas.edu, E-mail: mishak@utdallas.edu [Department of Physics, University of Texas at Dallas, Richardson, TX 75083 (United States)

2016-10-01

The scenario consistent with a wealth of observations for the missing mass problem is that of weakly interacting dark matter particles. However, arguments or proposals for a Newtonian or relativistic modified gravity scenario continue to be made. A distinguishing characteristic between the two scenarios is that dark matter particles can produce a gravitational effect, in principle, without the need of baryons while this is not the case for the modified gravity scenario where such an effect must be correlated with the amount of baryonic matter. We consider here ultra-faint dwarf (UFD) galaxies as a promising arena to test the two scenarios based on the above assertion. We compare the correlation of the luminosity with the velocity dispersion between samples of UFD and non-UFD galaxies, finding a significant loss of correlation for UFD galaxies. For example, we find for 28 non-UFD galaxies a strong correlation coefficient of −0.688 which drops to −0.077 for the 23 UFD galaxies. Incoming and future data will determine whether the observed stochasticity for UFD galaxies is physical or due to systematics in the data. Such a loss of correlation (if it is to persist) is possible and consistent with the dark matter scenario for UFD galaxies but would constitute a new challenge for the modified gravity scenario.

Screening for Natural Inhibitors of Topoisomerases I from Rhamnus davurica by Affinity Ultrafiltration and High-Performance Liquid Chromatography–Mass Spectrometry

Science.gov (United States)

Chen, Guilin; Guo, Mingquan

2017-01-01

Topoisomerase I (Topo I) catalyzes topological interconversion of duplex DNA during DNA replication and transcription, and has been deemed as important antineoplastic targets. In this study, the fraction R.d-60 from ethyl acetate extracts of Rhamnus davurica showed higher inhibitory rates against SGC-7901 and HT-29 compared with the R.d-30 fraction in vitro. However, the specific active components of R.d-60 fraction remain elusive. To this end, a method based on bio-affinity ultrafiltration and high performance liquid chromatography/electrospray mass spectrometry (HPLC- ESI-MS/MS) was developed to rapidly screen and identify the Topo I inhibitors in this fraction. The enrichment factors (EFs) were calculated to evaluate the binding affinities between the bioactive constituents and Topo I. As a result, eight ligands were identified and six of which with higher EFs showed more potential antitumor activity. Furthermore, antiproliferative assays in vitro (IC50 values) with two representative candidates (apigenin, quercetin) against SGC-7901, HT-29 and Hep G2 cells were conducted and further validated. Finally, the structure-activity relationships revealed that flavones contain a C2-C3 double bond of C ring exhibited higher bio-affinities to Topo I than those without it. This integrated method combining Topo I ultrafiltration with HPLC-MS/MS proved to be very efficient in rapid screening and identification of potential Topo I inhibitors from the complex extracts of medicinal plants, and could be further explored as a valuable high-throughput screening platform in the early drug discovery stage. PMID:28919906

Cheese whey protein recovery by ultrafiltration through transglutaminase (TG) catalysis whey protein cross-linking.

Science.gov (United States)

Wen-Qiong, Wang; Lan-Wei, Zhang; Xue, Han; Yi, Lu

2017-01-15

In whey ultrafiltration (UF) production, two main problems are whey protein recovery and membrane fouling. In this study, membrane coupling protein transglutaminase (TG) catalysis protein cross-linking was investigated under different conditions to find out the best treatment. We found that the optimal conditions for protein recovery involved catalyzing whey protein cross-linking with TG (40U/g whey proteins) at 40°C for 60min at pH 5.0. Under these conditions, the recovery rate was increased 15-20%, lactose rejection rate was decreased by 10%, and relative permeate flux was increase 30-40% compared to the sample without enzyme treatment (control). It was noticeable that the total resistance and cake resistance were decreased after enzyme catalysis. This was mainly due to the increased particle size and decreased zeta potential. Therefore, membrane coupling enzyme catalysis protein cross-linking is a potential means for further use. Copyright © 2016. Published by Elsevier Ltd.

Thin stillage fractionation using ultrafiltration: resistance in series model.

Science.gov (United States)

Arora, Amit; Dien, Bruce S; Belyea, Ronald L; Wang, Ping; Singh, Vijay; Tumbleson, M E; Rausch, Kent D

2009-02-01

The corn based dry grind process is the most widely used method in the US for fuel ethanol production. Fermentation of corn to ethanol produces whole stillage after ethanol is removed by distillation. It is centrifuged to separate thin stillage from wet grains. Thin stillage contains 5-10% solids. To concentrate solids of thin stillage, it requires evaporation of large amounts of water and maintenance of evaporators. Evaporator maintenance requires excess evaporator capacity at the facility, increasing capital expenses, requiring plant slowdowns or shut downs and results in revenue losses. Membrane filtration is one method that could lead to improved value of thin stillage and may offer an alternative to evaporation. Fractionation of thin stillage using ultrafiltration was conducted to evaluate membranes as an alternative to evaporators in the ethanol industry. Two regenerated cellulose membranes with molecular weight cut offs of 10 and 100 kDa were evaluated. Total solids (suspended and soluble) contents recovered through membrane separation process were similar to those from commercial evaporators. Permeate flux decline of thin stillage using a resistance in series model was determined. Each of the four components of total resistance was evaluated experimentally. Effects of operating variables such as transmembrane pressure and temperature on permeate flux rate and resistances were determined and optimum conditions for maximum flux rates were evaluated. Model equations were developed to evaluate the resistance components that are responsible for fouling and to predict total flux decline with respect to time. Modeling results were in agreement with experimental results (R(2) > 0.98).

Influence of fertilizer draw solution properties on the process performance and microbial community structure in a side-stream anaerobic fertilizer-drawn forward osmosis - ultrafiltration bioreactor.

Science.gov (United States)

Kim, Youngjin; Li, Sheng; Chekli, Laura; Phuntsho, Sherub; Ghaffour, Noreddine; Leiknes, TorOve; Shon, Ho Kyong

2017-09-01

In this study, a side-stream anaerobic fertilizer-drawn forward osmosis (FDFO) and ultrafiltration (UF) membrane bioreactor (MBR) hybrid system was proposed and operated for 55days. The FDFO performance was first investigated in terms of flux decline with various fertilizers draw solution. Flux decline was very severe with all fertilizers due to the absence of aeration and the sticky property of sludge. Flux recovery by physical cleaning varied significantly amongst tested fertilizers which seriously affected biofouling in FDFO via reverse salt flux (RSF). Besides, RSF had a significant impact on nutrient accumulation in the bioreactor. These results indicated that nutrient accumulation negatively influenced the anaerobic activity. To elucidate these phenomena, bacterial and archaeal community structures were analyzed by pyrosequencing. Results showed that bacterial community structure was affected by fertilizer properties with less impact on archaeal community structure, which resulted in a reduction in biogas production and an increase in nitrogen content. Copyright © 2017 Elsevier Ltd. All rights reserved.

Removal of radionuclides in drinking water by membrane treatment using ultrafiltration, reverse osmosis and electrodialysis reversal

International Nuclear Information System (INIS)

Montaña, M.; Camacho, A.; Serrano, I.; Devesa, R.; Matia, L.; Vallés, I.

2013-01-01

A pilot plant had been built to test the behaviour of ultrafiltration (UF), reverse osmosis (RO), and electrodialysis reversal (EDR) in order to improve the quality of the water supplied to Barcelona metropolitan area from the Llobregat River. This paper presents results from two studies to reduce natural radioactivity. The results from the pilot plant with four different scenarios were used to design the full-scale treatment plant built (SJD WTP). The samples taken at different steps of the treatment were analysed to determine gross alpha, gross beta and uranium activity. The results obtained revealed a significant improvement in the radiological water quality provided by both membrane techniques (RO and EDR showed removal rates higher than 60%). However, UF did not show any significant removal capacity for gross alpha, gross beta or uranium activities. RO was better at reducing the radiological parameters studied and this treatment was selected and applied at the full scale treatment plant. The RO treatment used at the SJD WTP reduced the concentration of both gross alpha and gross beta activities and also produced water of high quality with an average removal of 95% for gross alpha activity and almost 93% for gross beta activity at the treatment plant. -- Highlights: ► A study with a pilot plant using different membranes technologies was made. ► Big reduction on natural uranium and 40 K by reverse osmosis was found. ► Pilot plant and full-scale treatment plant behave similarly

Efficient purification of cell culture-derived classical swine fever virus by ultrafiltration and size-exclusion chromatography

Directory of Open Access Journals (Sweden)

Ruining WANG,Yubao ZHI,Junqing GUO,Qingmei LI,Li WANG,Jifei YANG,Qianyue JIN,Yinbiao WANG,Yanyan YANG,Guangxu XING,Songlin QIAO,Mengmeng ZHAO,Ruiguang DENG,Gaiping ZHANG

2015-09-01

Full Text Available Large-scale production of cell culture-based classical swine fever virus (CSFV vaccine is hampered by the adverse reactions caused by contaminants from host cell and culture medium. Hence, we have developed an efficient method for purifying CSFV from cell-culture medium. Pure viral particles were obtained with two steps of tangential-flow filtration (TFF and size-exclusion chromatography (SEC, and were compared with particles from ultracentrifugation by transmission electron microscopy (TEM, infectivity and recovery test, and real time fluorescent quantitative PCR (FQ-PCR. TFF concentrated the virus particles effectively with a retention rate of 98.5%, and 86.2% of viral particles were obtained from the ultrafiltration retentate through a Sepharose 4 F F column on a biological liquid chromatography system. CSFV purified by TFF-SEC or ultracentrifugation were both biologically active from 1.0×10-4.25 TCID50·mL-1 to 3.0×10-6.25 TCID50·mL-1, but the combination of TFF and SEC produced more pure virus particles than by ultracentrifugation alone. In addition, pure CSFV particles with the expected diameter of 40—60 nm were roughly spherical without any visible contamination. Mice immunized with CSFV purified by TFF-SEC produced higher antibody levels compared with immunization with ultracentrifugation-purified CSFV (P<0.05. The purification procedures in this study are reliable technically and feasible for purification of large volumes of viruses.

The development and standardization of testing methods for genetically modified organisms and their derived products.

Science.gov (United States)

Zhang, Dabing; Guo, Jinchao

2011-07-01

As the worldwide commercialization of genetically modified organisms (GMOs) increases and consumers concern the safety of GMOs, many countries and regions are issuing labeling regulations on GMOs and their products. Analytical methods and their standardization for GM ingredients in foods and feed are essential for the implementation of labeling regulations. To date, the GMO testing methods are mainly based on the inserted DNA sequences and newly produced proteins in GMOs. This paper presents an overview of GMO testing methods as well as their standardization. © 2011 Institute of Botany, Chinese Academy of Sciences.

New method for exopolysaccharide determination in culture broth using stirred ultrafiltration cells.

Science.gov (United States)

Bergmaier, D; Lacroix, C; Guadalupe Macedo, M; Champagne, C P

2001-10-01

A new method to remove simple carbohydrates from culture broth prior to the quantification of exopolysaccharides (EPS) was developed and validated for the EPS-producing strain, Lactobacillus rhamnosus RW-9595M. This method uses ultrafiltration (UF) in stirred cells followed by polysaccharide detection in the retentate by the phenol-sulfuric acid method. The UF method was compared with a conventional method based on ethanol extraction, dialysis, protein removal by trichloroacetic acid (TCA) and freeze-drying. EPS production during pH-controlled batch fermentations in basal minimum medium, whey permeate (WP). and whey permeate supplemented with yeast extract, minerals and Tween-80 (SWP) was determined by the new UF and conventional methods. EPS recovery by the new method ranged from 83% to 104% for EPS added in the concentration range 40-1,500 mg/l in 0.1 M NaCl solution or culture medium. The UF method was rapid (8 h), accurate and simple, and required only a small sample volume (1-5 ml). A very high maximum EPS production was measured in SWP by both the UF and conventional methods (1,718 and 1,755 mg/l).

Physical–chemical properties, separation performance, and fouling resistance of mixed-matrix ultrafiltration membranes

KAUST Repository

Hoek, Eric M.V.; Ghosh, Asim K.; Huang, Xiaofei; Liong, Monty; Zink, Jeffrey I.

2011-01-01

Herein we report on the formation and characterization of mixed-matrix ultrafiltration (UF) membranes hand-cast by nonsolvent induced phase inversion. We evaluated nanometer-to-micrometer sized inorganic fillers (silver, copper, silica, zeolite, and silver-zeolite) materials with polysulfone (PSf) as the polymeric dispersing matrix. In general, mixed-matrix membranes were rougher, more hydrophilic, and more mechanically robust. Only sub-micron zeolite-PSf mixed-matrix membranes exhibited simultaneous improvements in water permeability and solute selectivity; all other mixed-matrix membranes were more permeable, but less selective due to defects associated with poor polymer-filler binding. Protein and bacterial fouling resistance of mixed-matrix membranes containing silver, zeolite, and silver-zeolite nanoparticles were compared to a low-fouling, poly(acrylonitrile) (PAN) UF membrane. Zeolite and silver containing membranes exhibited better protein fouling resistance (due to higher hydrophilicity), whereas silver and silver-zeolite based membranes produce better bacterial fouling resistance due to antimicrobial properties. Overall, zeolite-PSf and silver exchanged zeolite-PSf membranes offered the best combination of improved permeability, selectivity, and fouling resistance - superior to the commercial PAN membrane. © 2011 Elsevier B.V.

Physical–chemical properties, separation performance, and fouling resistance of mixed-matrix ultrafiltration membranes

KAUST Repository

Hoek, Eric M.V.

2011-12-01

Herein we report on the formation and characterization of mixed-matrix ultrafiltration (UF) membranes hand-cast by nonsolvent induced phase inversion. We evaluated nanometer-to-micrometer sized inorganic fillers (silver, copper, silica, zeolite, and silver-zeolite) materials with polysulfone (PSf) as the polymeric dispersing matrix. In general, mixed-matrix membranes were rougher, more hydrophilic, and more mechanically robust. Only sub-micron zeolite-PSf mixed-matrix membranes exhibited simultaneous improvements in water permeability and solute selectivity; all other mixed-matrix membranes were more permeable, but less selective due to defects associated with poor polymer-filler binding. Protein and bacterial fouling resistance of mixed-matrix membranes containing silver, zeolite, and silver-zeolite nanoparticles were compared to a low-fouling, poly(acrylonitrile) (PAN) UF membrane. Zeolite and silver containing membranes exhibited better protein fouling resistance (due to higher hydrophilicity), whereas silver and silver-zeolite based membranes produce better bacterial fouling resistance due to antimicrobial properties. Overall, zeolite-PSf and silver exchanged zeolite-PSf membranes offered the best combination of improved permeability, selectivity, and fouling resistance - superior to the commercial PAN membrane. © 2011 Elsevier B.V.

Fatigue Life Assessment of Selected Engineering Materials Based on Modified Low-Cycle Fatigue Test

Directory of Open Access Journals (Sweden)

Maj M.

2013-03-01

Full Text Available In this study, the mechanical tests were carried out on ductile iron of EN-GJS-600-3 grade and on grey cast iron of EN-GJL-250 grade. The fatigue life was evaluated in a modified low-cycle fatigue test (MLCF, which enables the determination of parameters resulting from the Manson-Coffin-Morrow relationship. The qualitative and quantitative metallographic studies conducted by light microscopy on selected samples of ductile iron with spheroidal graphite and grey cast iron with lamellar graphite (showing only small variations in mechanical properties, confirmed also small variations in the geometrical parameters of graphite related with its content and morphological features.

Fatigue Life Assessment of Selected Engineering Materials Based on Modified Low-Cycle Fatigue Test

Directory of Open Access Journals (Sweden)

M. Maj

2013-01-01

Full Text Available In this study, the mechanical tests were carried out on ductile iron of EN-GJS-600-3 grade and on grey cast iron of EN-GJL-250 grade.The fatigue life was evaluated in a modified low-cycle fatigue test (MLCF, which enables the determination of parameters resulting fromthe Manson-Coffin-Morrow relationship.The qualitative and quantitative metallographic studies conducted by light microscopy on selected samples of ductile iron with spheroidalgraphite and grey cast iron with lamellar graphite (showing only small variations in mechanical properties, confirmed also smallvariations in the geometrical parameters of graphite related with its content and morphological features.

Wind tunnel tests of modified cross, hemisflo, and disk-gap-band parachutes with emphasis in the transonic range

Science.gov (United States)

Foughner, J. T., Jr.; Alexander, W. C.

1974-01-01

Transonic wind-tunnel studies were conducted with modified cross, hemisflo, and disk-gap-band parachute models in the wake of a cone-cylinder shape forebody. The basic cross design was modified with the addition of a circumferential constraining band at the lower edge of the canopy panels. The tests covered a Mach number range of 0.3 to 1.2 and a dynamic pressure range from 479 Newtons per square meter to 5746 Newtons per square meter. The parachute models were flexible textile-type structures and were tethered to a rigid forebody with a single flexible riser. Different size models of the modified cross and disk-gap-band canopies were tested to evaluate scale effects. Model reference diameters were 0.30, 0.61, and 1.07 meters (1.0, 2.0, and 3.5 ft) for the modified cross; and nominal diameters of 0.25 and 0.52 meter (0.83 and 1.7 ft) for the disk-gap-band; and 0.55 meter (1.8 ft) for the hemisflo. Reefing information is presented for the 0.61-meter-diameter cross and the 0.52-meter-diameter disk-gap-band. Results are presented in the form of the variation of steady-state average drag coefficient with Mach number. General stability characteristics of each parachute are discussed. Included are comments on canopy coning, spinning, and fluttering motions.

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.

Preparation, Characterization and Performance Studies of Active PVDF Ultrafiltration-Surfactants Membranes Containing PVP as Additive

International Nuclear Information System (INIS)

Nur Izzah Md Fadilah; Abdul Rahman Hassan

2016-01-01

The role of surfactants in the formation of active Poly(vinylidene fluoride) (PVDF) ultrafiltration (AUF) membranes was studied. The effect combination of surfactants that are Sodium dodecyl sulfate (SDS)/ Tween 80 and Tween 80/ Triton X-100 formulations on performance and morphological structures were investigated for the first time. The influence of surfactants blends on the membrane pores was also examined. Experimental data showed that combination of Tween 80/ Triton X-100 give the highest BSA permeation flux with a value of 285.51 Lm -2 h -1 . With combination of SDS/ Tween 80, the AUF membrane showed the highest protein rejection up to 93 % and 79 % for Bovine Serum Albumin (BSA) and Egg Albumin (EA), respectively. Moreover, membranes characterization demonstrated that the addition of SDS/ Tween 80 and Tween 80/ Triton X-100 were found to affect the performance, surface morphologies and membrane pores of AUF PVDF membranes. (author)

Liquid Whey Protein Concentrates Produced by Ultrafiltration as Primary Raw Materials for Thermal Dairy Gels

Directory of Open Access Journals (Sweden)

Marta Henriques

2017-01-01

Full Text Available The aim of this work is to study the gelation properties of liquid whey protein concentrates (LWPC produced by ultrafiltration (UF as raw material for thermally induced gels intended for food applications. LWPC thermal gelation was performed using different types of LWPC (non-defatted, defatted and diafiltered of different protein mass fractions and pH. Most of the produced gels showed viscoelastic behaviour. Non-defatted LWPC gave stronger heat-induced gels with a more cohesive microstructure, a higher water holding capacity and also higher elastic modulus (G’ and viscous modulus (G’’. Gel properties were not improved in products with lower content of non-protein compounds. As expected, the increase in protein mass fraction positively influences protein interactions. However, the pH is responsible for the equilibrium between attraction and repulsion forces in the gel components that influence gel hardness and water holding capacity.

Face/core mixed mode debond fracture toughness characterization using the modified TSD test method

DEFF Research Database (Denmark)

Berggreen, Christian; Quispitupa, Amilcar; Costache, Andrei

2014-01-01

The modified tilted sandwich debond (TSD) test method is used to examine face/core debond fracture toughness of sandwich specimens with glass/polyester face sheets and PVC H45 and H100 foam cores over a large range of mode-mixities. The modification was achieved by reinforcing the loaded face sheet....... The fracture process was inspected visually during and after testing. For specimens with H45 core the crack propagated in the core. For specimens with an H100 core, the crack propagated between the resin-rich layer and the face sheet. © The Author(s) 2013 Reprints and permissions: sagepub...... with a steel bar, and fracture testing of the test specimens was conducted over a range of tilt angles. The fracture toughness exhibited mode-mixity phase angle dependence, especially for mode II dominated loadings; although, the fracture toughness remained quite constant for mode I dominated crack loadings...

Enhancement of glucose uptake in muscular cell by soybean charged peptides isolated by electrodialysis with ultrafiltration membranes (EDUF): activation of the AMPK pathway.

Science.gov (United States)

Roblet, Cyril; Doyen, Alain; Amiot, Jean; Pilon, Geneviève; Marette, André; Bazinet, Laurent

2014-03-15

Soy peptides consumption has been associated with beneficial effects in type 2 diabetes patients. However, the peptide fractions responsible for these effects, and their mechanisms of action, have not been identified yet. In this study, we have isolated soybean peptides by electrodialysis with an ultrafiltration membrane (EDUF) at 50 V/100 kDa, and tested them for their capacity to improve glucose uptake in L6 muscle cells. We observed that these fractions were able to significantly enhance glucose uptake in the presence of insulin. The reported bioactivity would be due to the low molecular weight peptides (300-500 Da) recovered. Moreover, we observed that an enhancement of glucose uptake was correlated to the activation of the AMPK enzyme, well known for its capacity to increase glucose uptake in muscle cells. To our knowledge, this is the first time that bioactive peptides with glucose uptake activity have been isolated from a complex soy matrix, and that the implication of AMPK in it is demonstrated. Copyright © 2013 Elsevier Ltd. All rights reserved.

Assessing the treatment effects in apraxia of speech : introduction and evaluation of the Modified Diadochokinesis Test

NARCIS (Netherlands)

Hurkmans, Joost; Jonkers, Roel; Boonstra, Anne M.; Stewart, Roy E.; Reinders-Messelink, Heleen A.

2012-01-01

Background: The number of reliable and valid instruments to measure the effects of therapy in apraxia of speech (AoS) is limited. Aims: To evaluate the newly developed Modified Diadochokinesis Test (MDT), which is a task to assess the effects of rate and rhythm therapies for AoS in a multiple

Clay filter-aid in ultrafiltration (UF) of humic acid solution

KAUST Repository

Pontié , M.; Thekkedath, A.; Kecili, K.; Dach, H.; De Nardi, F.; Castaing, J.B.

2012-01-01

Fouling studies with three different molecular weight cut-off (MWCO) (100. kDa, 30. kDa and 10. kDa) membranes in regenerated cellulose were carried out in the presence of Acros humic acids (HA) at pH 3.0, 6.7 and 9.5. It was shown that the tighter membranes were less fouled compared with the higher MWCO membranes. 100. kDa membrane showed the highest degree of fouling. The role of pH showed that the highest degree of fouling happened at a neutral pH (pH 6.7) and the lowest degree of fouling happened at a basic pH (pH 9.5).Effectiveness of a novel pre-treatment method was applied to the 100kDa membrane. We added in the HA solution clay particles, homemade synthetized from natural bentonite and denoted Mont-CTAB. We observed a gain in productivity of 25%. 2D-fractal dimension parameter decreased under 1.5, showing a de-organization of the cake due to clay particles in/on the cake and a specific resistance of 4.4×10 11m/kg was obtained in presence of clays versus 3.6×10 14m/kg with HA alone. Finally the development of clay assisted ultrafiltration process changes the cake morphology limiting fouling impact and it is hope that for long term experiments, formation of a gel-layer should be limited. © 2012 Elsevier B.V..

Clay filter-aid in ultrafiltration (UF) of humic acid solution

KAUST Repository

Pontié, M.

2012-04-01

Fouling studies with three different molecular weight cut-off (MWCO) (100. kDa, 30. kDa and 10. kDa) membranes in regenerated cellulose were carried out in the presence of Acros humic acids (HA) at pH 3.0, 6.7 and 9.5. It was shown that the tighter membranes were less fouled compared with the higher MWCO membranes. 100. kDa membrane showed the highest degree of fouling. The role of pH showed that the highest degree of fouling happened at a neutral pH (pH 6.7) and the lowest degree of fouling happened at a basic pH (pH 9.5).Effectiveness of a novel pre-treatment method was applied to the 100kDa membrane. We added in the HA solution clay particles, homemade synthetized from natural bentonite and denoted Mont-CTAB. We observed a gain in productivity of 25%. 2D-fractal dimension parameter decreased under 1.5, showing a de-organization of the cake due to clay particles in/on the cake and a specific resistance of 4.4×10 11m/kg was obtained in presence of clays versus 3.6×10 14m/kg with HA alone. Finally the development of clay assisted ultrafiltration process changes the cake morphology limiting fouling impact and it is hope that for long term experiments, formation of a gel-layer should be limited. © 2012 Elsevier B.V..

Measurement of the viscoelastic compliance of the eustachian tube using a modified forced-response test.

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Ghadiali, Samir N; Federspiel, William J; Swarts, J Douglas; Doyle, William J

2002-01-01

Eustachian tube compliance (ETC) was suggested to be an important determinate of function. Previous attempts to quantify ETC used summary measures that are not clearly related to the physical properties of the system. Here, we present a new method for measuring ETC that conforms more closely to the engineering definition of compliance. The forced response test was modified to include oscillations in applied flow after the forced tubal opening. Pressure and flow were recorded during the standard and modified test in 12 anesthetized cynomolgus monkeys. The resulting pressure-flow, hysteresis loops were compared with those predicted by a simple fluid-structure model of the Eustachian tube with linear-elastic or viscoelastic properties. The tubal compliance index (TCI) and a viscoelastic compliance (C(v)) were calculated from these data for each monkey. The behavior of a viscoelastic, but not a linear elastic model accurately reproduced the experimental data for the monkey. The TCI and C(v) were linearly related, but the shared variance in these measures was only 63%. This new method for measuring ETC captures all information contained in the traditional TCI, but also provides information regarding the contribution of wall viscosity to Eustachian tube mechanics.

Influence of fertilizer draw solution properties on the process performance and microbial community structure in a side-stream anaerobic fertilizer-drawn forward osmosis – ultrafiltration bioreactor

KAUST Repository

Kim, Youngjin

2017-02-27

In this study, a side-stream anaerobic fertilizer-drawn forward osmosis (FDFO) and ultrafiltration (UF) membrane bioreactor (MBR) hybrid system was proposed and operated for 55 days. The FDFO performance was first investigated in terms of flux decline with various fertilizers draw solution. Flux decline was very severe with all fertilizers due to the absence of aeration and the sticky property of sludge. Flux recovery by physical cleaning varied significantly amongst tested fertilizers which seriously affected biofouling in FDFO via reverse salt flux (RSF). Besides, RSF had a significant impact on nutrient accumulation in the bioreactor. These results indicated that nutrient accumulation negatively influenced the anaerobic activity. To elucidate these phenomena, bacterial and archaeal community structures were analyzed by pyrosequencing. Results showed that bacterial community structure was affected by fertilizer properties with less impact on archaeal community structure, which resulted in a reduction in biogas production and an increase in nitrogen content.

Effects of Polarization on Mechanical Properties of Lead Zirconate Titanate Ceramics Evaluated by Modified Small Punch Tests

Science.gov (United States)

Deng, Qihuang; Fan, Yuchi; Wang, Lianjun; Xiong, Zhi; Wang, Hongzhi; Li, Yaogang; Zhang, Qinghong; Kawasaki, Akira; Jiang, Wan

2012-01-01

Pb(Zr,Ti)O3 (PZT) ceramics were prepared by the conventional mixed oxide method, and the strength of the resultant PZT ceramics was evaluated using modified small punch (MSP) tests. Load-displacement curve test results showed that the crack-initiation and fracture strengths of PZT ceramics decreased after polarization. The effect of the polarization accelerated the fatigue properties of PZT ceramics. Scanning electron microscopy (SEM) results showed that microcracks were formed before the maximum load in the MSP test, and the first load drop corresponded to crack initiation.

Meta-Analysis of Ultrafiltration versus Diuretics Treatment Option for Overload Volume Reduction in Patients with Acute Decompensated Heart Failure.

Science.gov (United States)

Barkoudah, Ebrahim; Kodali, Sindhura; Okoroh, Juliet; Sethi, Rosh; Hulten, Edward; Suemoto, Claudia; Bittencourt, Marcio Sommer

2015-05-01

Although diuretics are mainly used for the treatment of acute decompensated heart failure (ADHF), inadequate responses and complications have led to the use of extracorporeal ultrafiltration (UF) as an alternative strategy for reducing volume overloads in patients with ADHF. The aim of our study is to perform meta-analysis of the results obtained from studies on extracorporeal venous ultrafiltration and compare them with those of standard diuretic treatment for overload volume reduction in acute decompensated heart failure. MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials databases were systematically searched using a pre‑specified criterion. Pooled estimates of outcomes after 48 h (weight change, serum creatinine level, and all-cause mortality) were computed using random effect models. Pooled weighted mean differences were calculated for weight loss and change in creatinine level, whereas a pooled risk ratio was used for the analysis of binary all-cause mortality outcome. A total of nine studies, involving 613 patients, met the eligibility criteria. The mean weight loss in patients who underwent UF therapy was 1.78 kg [95% Confidence Interval (CI): -2.65 to -0.91 kg; p diuretic therapy. The post-intervention creatinine level, however, was not significantly different (mean change = -0.25 mg/dL; 95% CI: -0.56 to 0.06 mg/dL; p = 0.112). The risk of all-cause mortality persisted in patients treated with UF compared with patients treated with standard diuretics (Pooled RR = 1.00; 95% CI: 0.64-1.56; p = 0.993). Compared with standard diuretic therapy, UF treatment for overload volume reduction in individuals suffering from ADHF, resulted in significant reduction of body weight within 48 h. However, no significant decrease of serum creatinine level or reduction of all-cause mortality was observed.

New aspects of the possible sites of ultrafiltration in annelids (oligochaeta).

Science.gov (United States)

Hansen, U

1995-02-01

Electron microscopic investigations of blood vessels were conducted to show sites of filtration such as podocytes or fenestrated endothelia. The endothelia of the blood vessels of Aelosoma hemprichi, Nais elinguis, Dero obtusa and Enchytraeus buchholzi consist of myoendothelial cells, chloragocytes and podocytes. The podocytes form large archs over a considerable area of the vessels. On the lumen side of the vessel there are several columnar processes which split into numerous small pedicels. The gaps between the adjacent pedicles are bridged by slit membranes. The podocytes are restricted to the front part of the ventral vessel. They are presumed to form a filtration surface. Furthermore, some parts of the ventral vessel are formed by a fenestrated endothelium, mainly in Enchytraeus buchholzi. In the vascular system of E. buchholzi two separate filtration sites were found. Additionally to the filtration site between ventral vessel and coelomic cavity a second filtration site was found in the front part of the body between blood sinus and coelomic cavity. In such areas the basement membrane is the only continuous layer between the blood vessel and the coelomic cavity. Its thickness is in the range of 40 nm. Possible filtration sites in the form of podocytes and irregular fenestrations could be localized at the border between the blood compartment and the coelomic compartment. It can be presumed that the primary urine may be formed by ultrafiltration of blood.

Mild dehydration modifies the cerebrovascular response to the cold pressor test.

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Perry, Blake G; Bear, Tracey L K; Lucas, Samuel J E; Mündel, Toby

2016-01-01

The cold pressor test (CPT) is widely used in clinical practice and physiological research. It is characterized by a robust autonomic response, with associated increases in heart rate (HR), mean arterial pressure (MAP) and mean middle cerebral artery blood flow velocity (MCAv(mean)). Hydration status is not commonly reported when conducting this test, yet blood viscosity alone can modulate MCAv(mean), potentially modifying the MCAv(mean) response to the CPT. We investigated the effect of mild dehydration on the physiological response to the CPT in 10 healthy men (mean ± SD: age 28 ± 5 years; body mass 83 ± 5 kg). All participants completed two CPTs, cold water (0°C) immersion of both feet for 90 s, with the order of the euhydration and dehydration trials counterbalanced. Beat-to-beat MCAv, MAP, HR and breath-by-breath partial pressure of end-tidal CO2 (P(ET,CO2)) were measured continuously. Participants' pain perception was measured 1 min into the CPT using a visual analog scale (no pain = 0; maximal pain = 10). Dehydration significantly elevated plasma osmolality and urine specific gravity and reduced body mass (all P 0.05). After 90 s of immersion, the change in MCAv(mean) from baseline was less in the dehydration compared with the euhydration trial (change 0 ± 5 versus 7 ± 7 cm s(-1), P = 0.01), as was P(ET,CO2) (change -3 ± 2 versus 0 ± 3 mmHg, P = 0.02). Dehydration was associated with greater relative pain sensation during the CPT (7.0 ± 1.3 vs 5.8 ± 1.8, P = 0.02). Our results demonstrate that mild dehydration can modify the cerebrovascular response to the CPT, with dehydration increasing perceived pain, lowering P ET ,CO2 and, ultimately, blunting the MCAv(mean) response. © 2015 The Authors. Experimental Physiology © 2015 The Physiological Society.

Evaluation of permanent deformation characteristics of unmodified and Polyethylene Terephthalate modified asphalt mixtures using dynamic creep test

International Nuclear Information System (INIS)

Baghaee Moghaddam, Taher; Soltani, Mehrtash; Karim, Mohamed Rehan

2014-01-01

Highlights: • Waste PET was utilized as modifier in asphalt mixture. • Deformation characteristics of asphalt mixtures were assessed. • Dynamic creep test was conducted at different temperatures and stress levels. • Permanent deformation models were introduced. - Abstract: One of the major types of plastics that can be found in Municipal Solid Waste (MSW) is Polyethylene Terephthalate (PET) which is a non-biodegradable semi-crystalline thermoplastic polymer, and is considered as polyester material. Generating large amount of waste PET, mainly as bottles, would cause environmental hazards by disposing in landfills. This paper aims to evaluate effects of utilizing waste PET flakes as modifier in asphalt mixture as an alternative solution to overcome the potential risks arise from producing large amount of waste PET as well as evaluating the deformation characteristics of unmodified and PET modified asphalt mixtures. To achieve this aim, different percentages of PET were designated for this investigation, namely: 0%, 0.2%, 0.4%, 0.6%, 0.8% and 1% by weight of aggregate particles, and dynamic creep test was performed at different stress levels (300 kPa and 400 kPa) and temperatures (10 °C, 25 °C and 40 °C). Consequently, Zhou three-stage model was developed. The results showed that permanent deformation characteristics of asphalt mixture were considerably improved by utilization of PET modification, when the permanent strain was remarkably decreased in PET modified mixture compared to the conventional mixture at all stress levels and temperatures. Besides, based on Zhou model, it was concluded that elastic and visco-elastic properties of asphalt mixture were improved by application of PET modification

Assessing the Treatment Effects in Apraxia of Speech: Introduction and Evaluation of the Modified Diadochokinesis Test

Science.gov (United States)

Hurkmans, Joost; Jonkers, Roel; Boonstra, Anne M.; Stewart, Roy E.; Reinders-Messelink, Heleen A.

2012-01-01

Background: The number of reliable and valid instruments to measure the effects of therapy in apraxia of speech (AoS) is limited. Aims: To evaluate the newly developed Modified Diadochokinesis Test (MDT), which is a task to assess the effects of rate and rhythm therapies for AoS in a multiple baseline across behaviours design. Methods: The…

Study of Antiultraviolet Asphalt Modifiers and Their Antiageing Effects

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Jinxuan Hu

2017-01-01

Full Text Available Ultraviolet (UV radiation causes serious ageing problems on pavement surface. In recent years, different UV blocking materials have been used as modifiers to prevent asphalt ageing during the service life of the pavement. In this study, three different materials have been used as modifiers in base asphalt to test their UV blocking effects: layered double hydroxides (LDHs, organomontmorillonite (OMMT, and carbon black (CB. UV ageing was applied to simulate the ageing process and softening point, penetration, ductility, DSR (Dynamic Shear Rheometer test, and Fourier Transform Infrared Spectroscopy (FTIR test were conducted to evaluate the anti-UV ageing effects of the three UV blocking modifiers. Physical property tests show that base asphalt was influenced more seriously by UV radiation compared to the modified asphalt. DSR test results indicate that the complex modulus of asphalt before UV ageing is increased because of modifiers, while the complex modulus of base asphalt after UV ageing is higher than that of the modified asphalt, which shows that the UV blocking modifiers promote the antiageing effects of asphalt. FTIR test reveals that the increment of carbonyl groups and sulfoxide groups of modified asphalt is less than that in base asphalt. Tests indicate the best UV blocking effect results for samples with LDHs and the worst UV blocking effect results for samples with CB.

Ultrafiltration of thin stillage from conventional and e-mill dry grind processes.

Science.gov (United States)

Arora, Amit; Dien, Bruce S; Belyea, Ronald L; Wang, Ping; Singh, Vijay; Tumbleson, M E; Rausch, Kent D

2011-05-01

We used ultrafiltration (UF) to evaluate membrane filtration characteristics of thin stillage and determine solids and nutrient compositions of filtered streams. To obtain thin stillage, corn was fermented using laboratory methods. UF experiments were conducted in batch mode under constant temperature and flow rate conditions. Two regenerated cellulose membranes (10 and 100 kDa molecular weight cutoffs) were evaluated with the objective of retaining solids as well as maximizing permeate flux. Optimum pressures for 10 and 100 kDa membranes were 207 and 69 kPa, respectively. Total solids, ash, and neutral detergent fiber contents of input TS streams of dry grind and E-Mill processes were similar; however, fat and protein contents were different (p stillage fractionation had higher mean total solids contents (27.6% to 27.8%) compared to E-Mill (22.2% to 23.4%). Total solids in retentate streams were found similar to those from commercial evaporators used in industry (25% to 35% total solids). Fat contents of retentate streams ranged from 16.3% to 17.5% for the conventional process. A 2% increment in fat concentration was observed in the E-Mill retentate stream. Thin stillage ash content was reduced 60% in retentate streams.

Organic micro-pollutants’ removal via anaerobic membrane bioreactor with ultrafiltration and nanofiltration

KAUST Repository

Wei, Chunhai

2015-12-15

The removal of 15 organic micro-pollutants (OMPs) in synthetic municipal wastewater was investigated in a laboratory-scale mesophilic anaerobic membrane bioreactor (AnMBR) using ultrafiltration and AnMBR followed by nanofiltration (NF), where powdered activated carbon (PAC) was added to enhance OMPs removal. No significant effects of OMPs spiking and NF connection on bulk organics removal and biogas production were observed. Amitriptyline, diphenhydramine, fluoxetine, sulfamethoxazole, TDCPP and trimethoprim showed readily biodegradable characteristics with consistent biological removal over 80%. Atrazine, carbamazepine, DEET, Dilantin, primidone and TCEP showed refractory characteristics with biological removal below 40%. Acetaminophen, atenolol and caffeine showed a prolonged adaption time of around 45 d, with initial biological removal below 40% and up to 50-80% after this period. Most readily biodegradable OMPs contained a strong electron donating group. Most refractory OMPs contained a strong electron withdrawing group or a halogen substitute. NF showed consistent high rejection of 80-92% with an average of 87% for all OMPs, which resulted in higher OMPs removal in AnMBR-NF than in AnMBR alone, especially for refractory OMPs. Limited sorption performance of PAC for OMPs removal was mainly due to low and batch dosage (100 mg/L) as well as the competitive sorption caused by bulk organics.

RECOVERY OF PROTEIN FROM MUNG BEAN STARCH PROCESSING WASTEWATER BY ROTATING ULTRAFILTRATION

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PENPORN SRINIWORN

2016-07-01

Full Text Available Mung bean wastewater containing valuable protein is very potential to be recovered for reuse. In this study, rotary disk ultrafiltration was employed to recover this protein. The effects of transmembrane pressure (TMP and membrane rotational speeds on process efficiency were studied and the optimum condition was chosen based on membrane permeate flux and protein retention. The results suggested that the use of TMP of 1.2 bar and rotating speed of 1,683 rpm under total recycle mode tended to achieve highest permeate flux (43 L/m3h compared to those using lower TMP and rotating speeds. The permeate fluxes under total recycle mode and batch concentration mode tended to increase with processing time, indicating the effectiveness of rotating shear force. In addition, the effect of stabilization technique on process performance under batch concentration mode was also studied. However, the variable did not show positive impacts on permeate flux and protein retention improvement. The optimum condition to achieve volume concentration factor (VCF of 5 was TMP of 1.2 bar and rotating speed of 1,403 rpm without stabilization. Under this condition, the average flux, protein retention and energy consumption were 42 L/m2h, 96% and 81 kWh/m3, respectively.

Enzymatic treatment for controlling irreversible membrane fouling in cross-flow humic acid-fed ultrafiltration

International Nuclear Information System (INIS)

Yu, Chien-Hwa; Fang, Lung-Chen; Lateef, Shaik Khaja; Wu, Chung-Hsin; Lin, Cheng-Fang

2010-01-01

Exploring reasonable ways to remove foulant is of great importance in order to allow sustainable operation of ultrafiltration (UF) membranes in water/wastewater treatment technology. Compounds of organic and inorganic origin largely contribute to irreversible fouling. This study attempted to remove problem of UF membrane fouling by using four different enzymes including α-amylase, lipase, cellulase and protease. This investigation showed that none of the above mentioned enzymes was found to be effective for the removal of foulant when used alone. However, when these enzymes were used in combination with NaOH and citric acid, about 90% cleaning was achieved. The addition of non-ionic surfactant to the enzymatic solution appears to increase the efficiency of flux recovery by reducing the adhesion of foulant species to the membrane surface through the decrease of contact angle. Field emission gun scanning electron microscopy, Fourier transform infrared spectroscopy and atomic force microscopy (AFM) techniques were employed to qualitatively illustrate the foulant characteristics. The surface roughness through AFM was used to explain the potential mechanism for the enzymatic cleaning.

Enzymatic treatment for controlling irreversible membrane fouling in cross-flow humic acid-fed ultrafiltration

Energy Technology Data Exchange (ETDEWEB)

Yu, Chien-Hwa [Department of Civil and Environment Engineering, Nanya Institute of Technology, Taoyuan, Taiwan (China); Fang, Lung-Chen; Lateef, Shaik Khaja [Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Taiwan (China); Wu, Chung-Hsin, E-mail: chunghsinwu@yahoo.com.tw [Department of Chemical and Materials Engineering, National Kaohsiung University of Applied Sciences, 415 Chien Kung Road, Kaohsiung 807, Taiwan (China); Lin, Cheng-Fang [Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Taiwan (China)

2010-05-15

Exploring reasonable ways to remove foulant is of great importance in order to allow sustainable operation of ultrafiltration (UF) membranes in water/wastewater treatment technology. Compounds of organic and inorganic origin largely contribute to irreversible fouling. This study attempted to remove problem of UF membrane fouling by using four different enzymes including {alpha}-amylase, lipase, cellulase and protease. This investigation showed that none of the above mentioned enzymes was found to be effective for the removal of foulant when used alone. However, when these enzymes were used in combination with NaOH and citric acid, about 90% cleaning was achieved. The addition of non-ionic surfactant to the enzymatic solution appears to increase the efficiency of flux recovery by reducing the adhesion of foulant species to the membrane surface through the decrease of contact angle. Field emission gun scanning electron microscopy, Fourier transform infrared spectroscopy and atomic force microscopy (AFM) techniques were employed to qualitatively illustrate the foulant characteristics. The surface roughness through AFM was used to explain the potential mechanism for the enzymatic cleaning.

Performance of Hollow Fiber Ultrafiltration Membranes in the Clarification of Blood Orange Juice

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Carmela Conidi

2015-12-01

Full Text Available The clarification of blood orange juice by ultrafiltration (UF was investigated by using three hollow fiber membrane modules characterized by different membrane materials (polysulfone (PS and polyacrylonitrile (PAN and molecular weight cut-off (MWCO (50 and 100 kDa. The performance of selected membranes was investigated in terms of productivity and selectivity towards total anthocyanin content (TAC, total phenolic content (TPC, and total antioxidant activity (TAA. All selected membranes allowed a good preservation of antioxidant compounds; however, the most suitable membrane for the clarification of the juice was found to be the PS 100 kDa membrane. In optimized operating conditions this membrane exhibited steady-state fluxes of 7.12 L/m2h, higher than those measured for other investigated membranes. Rejections towards TPC and TAA were of the order of 17.5% and 15%, respectively. These values were lower than those determined for PS 50 kDa and PAN 50 kDa membranes. In addition, the PS 100 kDa membrane exhibited a lower rejection (7.3% towards TAC when compared to the PS 50 kDa membrane (9.2%.

Performance on the modified star excursion balance test at the time of return to sport following anterior cruciate ligament reconstruction.

Science.gov (United States)

Clagg, Sarah; Paterno, Mark V; Hewett, Timothy E; Schmitt, Laura C

2015-06-01

Cross-sectional. Objectives To compare performance on the modified Star Excursion Balance Test (SEBT) between participants with anterior cruciate ligament reconstruction (ACLR) at the time of return to sport and uninjured control participants. The modified SEBT is a clinical tool to assess neuromuscular control deficits. Deficits in dynamic stability and neuromuscular control persist after ACLR, but assessment with the modified SEBT in this population at the time of return to sport has not been reported. Sixty-six participants (mean age, 17.6 years) at the time of return to sport following unilateral primary ACLR (ACLR group) and 47 uninjured participants (mean age, 17.0 years) serving as a control group participated. For the modified SEBT, the anterior, posteromedial, and posterolateral reach distances were recorded. Lower extremity muscle strength was quantified with isokinetic dynamometry. Independent-sample t tests were used to evaluate performance differences between the ACLR group and the control group and between the ACLR subgroups. In the ACLR group, bivariate correlations determined the association of modified SEBT performance with time since surgery and lower extremity muscle strength. The ACLR group had lower anterior reach distances on the involved and uninvolved limbs compared to the control group. There were no differences observed between groups in reach distances for the posteromedial and posterolateral directions or in limb symmetry indices for any of the reach directions. In the ACLR group, time from surgery and meniscal status at the time of ACLR did not influence modified SEBT performance, whereas participants with patellar bone-tendon-bone grafts had a lower posterolateral reach distance compared to those with hamstring grafts. In the ACLR group, involved-limb hip abduction strength positively correlated with all reach distances, and quadriceps strength positively correlated with posterolateral reach. At the time of return to sport

Modeling the improvement of ultrafiltration membrane mass transfer when using biofiltration pretreatment in surface water applications.

Science.gov (United States)

Netcher, Andrea C; Duranceau, Steven J

2016-03-01

In surface water treatment, ultrafiltration (UF) membranes are widely used because of their ability to supply safe drinking water. Although UF membranes produce high-quality water, their efficiency is limited by fouling. Improving UF filtrate productivity is economically desirable and has been attempted by incorporating sustainable biofiltration processes as pretreatment to UF with varying success. The availability of models that can be applied to describe the effectiveness of biofiltration on membrane mass transfer are lacking. In this work, UF water productivity was empirically modeled as a function of biofilter feed water quality using either a quadratic or Gaussian relationship. UF membrane mass transfer variability was found to be governed by the dimensionless mass ratio between the alkalinity (ALK) and dissolved organic carbon (DOC). UF membrane productivity was optimized when the biofilter feed water ALK to DOC ratio fell between 10 and 14. Copyright © 2015 Elsevier Ltd. All rights reserved.

An enquiry on appropriate selection of polymers for preparation of polymeric nanosorbents and nanofiltration/ultrafiltration membranes for hormone micropollutants removal from water effluents.

Science.gov (United States)

Khansary, Milad Asgarpour; Mellat, Mostafa; Saadat, Seyed Hassan; Fasihi-Ramandi, Mahdi; Kamali, Mehdi; Taheri, Ramezan Ali

2017-02-01

To analyze polymeric nanosorbents and nanofiltration/ultrafiltration membranes for hormone micropollutants removal from water effluents, here an in-through investigation on the suitability and compatibility of various polymers has been carried out. For this work, estradiol, estrone, testosterone, progesterone, estriol, mestranol, and ethinylestradiol were considered. A total number of 452 polymers were analyzed and initially screened using Hansen solubility parameters. The identified good pairs of hormones and polymers then were examined to obtain the equilibrium capacity of hormones removal from water effluents using a modified Flory-Huggins model. A distribution coefficient was defined as the ratio of hormones in water effluent phase and polymer phase. For removal of mestranol, estradiol and ethinylestradiol, no compatible polymer was identified based on initial screening of collected database. Three compatible polymers were identified for estriol. For progesterone, a wide variety of polymers was identified as good matching of polar, dispersion and hydrogen forces contributions can be observed for these pairs. For estrone, only two polymers can be proposed due to the mismatch observed between polar, dispersion and hydrogen forces contributions of other polymers and this hormone. The phase calculations showed that not all the identified good pairs could be used for practical separation applications. The domain of applicability of each good pair was investigated and potential polymers for practical micropollutants removal together with their removal capacity were represented in terms of phase envelops. The theoretical approach follows fundamental chemical thermodynamic equations and then can be simply applied for any system of interest. Copyright © 2016 Elsevier Ltd. All rights reserved.

Genetically modified foods and allergy.

Science.gov (United States)

Lee, T H; Ho, H K; Leung, T F

2017-06-01

2015 marked the 25th anniversary of the commercial use and availability of genetically modified crops. The area of planted biotech crops cultivated globally occupies a cumulative two billion hectares, equivalent to twice the land size of China or the United States. Foods derived from genetically modified plants are widely consumed in many countries and genetically modified soybean protein is extensively used in processed foods throughout the industrialised countries. Genetically modified food technology offers a possible solution to meet current and future challenges in food and medicine. Yet there is a strong undercurrent of anxiety that genetically modified foods are unsafe for human consumption, sometimes fuelled by criticisms based on little or no firm evidence. This has resulted in some countries turning away food destined for famine relief because of the perceived health risks of genetically modified foods. The major concerns include their possible allergenicity and toxicity despite the vigorous testing of genetically modified foods prior to marketing approval. It is imperative that scientists engage the public in a constructive evidence-based dialogue to address these concerns. At the same time, improved validated ways to test the safety of new foods should be developed. A post-launch strategy should be established routinely to allay concerns. Mandatory labelling of genetically modified ingredients should be adopted for the sake of transparency. Such ingredient listing and information facilitate tracing and recall if required.

Field testing and exploitation of genetically modified cassava with low-amylose or amylose-free starch in Indonesia

NARCIS (Netherlands)

Koehorst-van Putten, H.J.J.; Sudarmonowati, E.; Herman, M.; Pereira-Bertram, I.J.; Wolters, A.M.A.; Meima, H.; Vetten, de N.; Raemakers, C.J.J.M.; Visser, R.G.F.

2012-01-01

The development and testing in the field of genetically modified -so called- orphan crops like cassava in tropical countries is still in its infancy, despite the fact that cassava is not only used for food and feed but is also an important industrial crop. As traditional breeding of cassava is

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

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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.

Field testing genetically modified organisms: framework for decisions

National Research Council Canada - National Science Library

National Research Council Staff

1989-01-01

... on Scientific Evaluation of the Introduction of Genetically Modified Microoganisms and Plants into the Environment Board on Biology Commission on Life Sciences National Research Council NATIONAL ACADEMY PRESS Washington, D.C. 1989 i Copyrightthe cannot be not from book, paper however, version for formatting, original authoritative the typesetting-s...

Measurements of serum-free thyroid hormone concentrations by ultrafiltration

International Nuclear Information System (INIS)

Konno, Norimichi; Hagiwara, Kohji; Taguchi, Hideo; Murakami, Shigeki; Taguchi, Shizuko

1987-01-01

An ultrafiltration method (UF) for measuring free thyroxine (FT 4 ) and free triiodothyronine (FT 3 ) using the Diaflow YM membrane (Centricon-10) is described. The results are compared with those by equilibrium dialysis (ED) and also by mathematical calculations derived from T 4 , T 3 , and binding protein concentrations. The precision with the UF method was excellent. The normal ranges of FT 4 and FT 3 by the three methods are all comparable. There was a high degree of correlation of FT 4 or FT 3 results by UF with those by ED and by calculation (r = 0.940 - 0.974, n = 161, P 4 and FT 3 by all methods agreed well for hyperthyroidism, hypothyroidism, and for patients with low T 4 -binding globulin. The mean FT 3 in pregnancy was lower than the normal value for all methods, and FT 4 concentrations by UF and calculation also decreased in late pregnancy. The mean FT 4 by UF and ED in low T 3 syndrome were significantly higher than in the normal controls, while the calculated FT 4 was lower. The FT 3 in low T 3 syndrome distributed normal to subnormal in all methods. These results indicate that a) the UF method is a reliable reference method for measuring FT 4 and FT 3 concentrations; b) the UF results agree well with those by ED and also with theoretically derived values in subjects with thyroid diseases and TBG abnormalities; c) for patients with low T 3 syndrome, the FT 4 results obtained by UF and ED are similarly discrepant from the calculated results, implying the existence of binding inhibitor(s) which affect both UF and ED measurements. (author)

Polysulfone hemodiafiltration membranes with enhanced anti-fouling and hemocompatibility modified by poly(vinyl pyrrolidone) via in situ cross-linked polymerization.

Science.gov (United States)

Zhu, Lijing; Song, Haiming; Wang, Jiarong; Xue, Lixin

2017-05-01

Poly(vinyl pyrrolidone) (PVP) and its copolymers have been widely employed for the modification of hemodiafiltration membranes due to their excellent hydrophilicity, antifouling and hemocompatibility. However, challenges still remain to simplify the modification procedure and to improve the utilization efficiency. In this paper, antifouling and hemocompatibility polysulfone (PSf) hemodiafiltration membranes were fabricated via in situ cross-linked polymerization of vinyl pyrrolidone (VP) and vinyltriethoxysilane (VTEOS) in PSf solutions and non-solvent induced phase separation (NIPS) technique. The prepared membranes were characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM), which suggested that VP and VTEOS have been cross-linked copolymerized in PSf membranes. The modified PSf membranes with high polymer content showed improved hydrophilicity, ultrafiltration and protein antifouling ability. In addition, the modified PSf membranes showed lower protein adsorption, inhibited platelet adhesion and deformation, prolonged the activated partial thromboplastin time (APTT), prothrombin time (PT), and decreased the content of fibrinogen (FIB) transferring to fibrin, indicating enhanced hemocompatibility. In a word, the present work provides a simple and effective one-step modification method to construct PSf membranes with improved hydrophilicity, antifouling and hemocompatibility. Copyright © 2017 Elsevier B.V. All rights reserved.

Dustiness test of nanopowders using a standard rotating drum with a modified sampling train

International Nuclear Information System (INIS)

Tsai, Chuen-Jinn; Wu, Chien-Hsien; Leu, Ming-Long; Chen, Sheng-Chieh; Huang, Cheng-Yu; Tsai, Perng-Jy; Ko, Fu-Hsiang

2009-01-01

The standard rotating drum tester was used to determine the dustiness of two nanopowders, nano-TiO 2 and fine ZnO, in standard 1-min tests. Then, the sampling train was modified to determine the number and mass distributions of the generated particles in the respirable size range using a Scanning Mobility Particle Sizer (SMPS), an Aerodynamic Particle Sizer (APS) and a Multi-orifice Uniform Deposit Impactor (MOUDI) in the 30-min tests. It was found that very few particles below 100 nm were generated and the released rate of particles decreased with increasing rotation time for both nanopowders in the 30-min tests. Due to the fluffy structure of the released TiO 2 agglomerated particles, the mass distributions measured by the MOUDI showed large differences with those determined by the APS assuming the apparent bulk densities of the powders. The differences were small for the ZnO agglomerates, which were more compact than the TiO 2 agglomerates.

Testing modified gravity at large distances with the HI Nearby Galaxy Survey's rotation curves

Science.gov (United States)

Mastache, Jorge; Cervantes-Cota, Jorge L.; de la Macorra, Axel

2013-03-01

Recently a new—quantum motivated—theory of gravity has been proposed that modifies the standard Newtonian potential at large distances when spherical symmetry is considered. Accordingly, Newtonian gravity is altered by adding an extra Rindler acceleration term that has to be phenomenologically determined. Here we consider a standard and a power-law generalization of the Rindler modified Newtonian potential. The new terms in the gravitational potential are hypothesized to play the role of dark matter in galaxies. Our galactic model includes the mass of the integrated gas, and stars for which we consider three stellar mass functions (Kroupa, diet-Salpeter, and free mass model). We test this idea by fitting rotation curves of seventeen low surface brightness galaxies from the HI Nearby Galaxy Survey (THINGS). We find that the Rindler parameters do not perform a suitable fit to the rotation curves in comparison to standard dark matter profiles (Navarro-Frenk-White and Burkert) and, in addition, the computed parameters of the Rindler gravity show a high spread, posing the model as a nonacceptable alternative to dark matter.

Peritoneal transport in CAPD patients with permanent loss of ultrafiltration capacity

International Nuclear Information System (INIS)

Heimbuerger, O.W.; Waniewski, J.; Werynski, A.; Tranaeus, A.; Lindholm, B.

1990-01-01

During a 10 year period, 14 out of 227 patients (6.2%) undergoing continuous ambulatory peritoneal dialysis (CAPD) developed permanent loss of ultrafiltration capacity (UFC). The risk of UFC loss increased from 2.6% after one year to 30.9% after six years of treatment. A six hour, single dwell study with glucose 3.86% dialysis fluid was carried out in nine of the UFC loss patients and in 18 CAPD patients with normal UFC. Intraperitoneal dialysate volumes were calculated using 131I-tagged albumin (RISA) as volume marker with a correction applied for its elimination from the peritoneal cavity. The RISA elimination coefficient (KE), which can serve as an estimation of the upper limit of the lymphatic flow, was also calculated. Diffusive mass transport coefficients (KBD) for investigated solutes (glucose, creatinine, urea, potassium, total protein, albumin and beta 2-microglobulin) were calculated during a period of dialysate isovolemia. Two patterns of UFC loss were observed: (a) seven patients had high KBD values for small solutes resulting in rapid uptake of glucose, whereas KBD values for proteins were normal; (b) two patients had normal KBD values but a threefold increase both in the fluid reabsorption rate and KE. We conclude that loss of the osmotic driving force (due to increased diffusive mass transport for small solutes) and increased fluid reabsorption (possibly due to increased lymphatic reabsorption) are the two major causes of permanent loss of UFC in CAPD patients

Identification of tyrosinase specific inhibitors from Xanthium strumarium fruit extract using ultrafiltration-high performance liquid chromatography.

Science.gov (United States)

Wang, Zhiqiang; Hwang, Seung Hwan; Huang, Bo; Lim, Soon Sung

2015-10-01

In this study, a strategy based on ultrafiltration-high performance liquid chromatography coupled with diode array detection (UF-HPLC-DAD) was proposed for screening tyrosinase specific inhibitors in Xanthii fructus. The false negatives were distinguished by optimizing the UF-HPLC-DAD parameters to reduce the background noise; the false positives were distinguished by introducing a blocked tyrosinase in the control group for comparison. To obtain the best blocker, the competitive experiments were performed using various known ligands. Using this strategy, three competitive inhibitors (protocatechuic acid; 3,5-di-O-caffeoylquinic acid; and 1,5-di-O-caffeoylquinic acid) and one mixed-type inhibitor (chlorogenic acid) were identified. These results were verified using tyrosinase inhibition assay, kinetic analysis, and structural simulation of the complex. Our experimental results suggest that the proposed strategy could be useful for high-throughput identification of tyrosinase specific inhibitors in natural products. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparison of two treatments for the removal of selected organic micropollutants and bulk organic matter: conventional activated sludge followed by ultrafiltration versus membrane bioreactor.

Science.gov (United States)

Sahar, E; Ernst, M; Godehardt, M; Hein, A; Herr, J; Kazner, C; Melin, T; Cikurel, H; Aharoni, A; Messalem, R; Brenner, A; Jekel, M

2011-01-01

The potential of membrane bioreactor (MBR) systems to remove organic micropollutants was investigated at different scales, operational conditions, and locations. The effluent quality of the MBR system was compared with that of a plant combining conventional activated sludge (CAS) followed by ultrafiltration (UF). The MBR and CAS-UF systems were operated and tested in parallel. An MBR pilot plant in Israel was operated for over a year at a mixed liquor suspended solids (MLSS) range of 2.8-10.6 g/L. The MBR achieved removal rates comparable to those of a CAS-UF plant at the Tel-Aviv wastewater treatment plant (WWTP) for macrolide antibiotics such as roxythromycin, clarithromycin, and erythromycin and slightly higher removal rates than the CAS-UF for sulfonamides. A laboratory scale MBR unit in Berlin - at an MLSS of 6-9 g/L - showed better removal rates for macrolide antibiotics, trimethoprim, and 5-tolyltriazole compared to the CAS process of the Ruhleben sewage treatment plant (STP) in Berlin when both were fed with identical quality raw wastewater. The Berlin CAS exhibited significantly better benzotriazole removal and slightly better sulfamethoxazole and 4-tolyltriazole removal than its MBR counterpart. Pilot MBR tests (MLSS of 12 g/L) in Aachen, Germany, showed that operating flux significantly affected the resulting membrane fouling rate, but the removal rates of dissolved organic matter and of bisphenol A were not affected.

Influence of the gripping fixture on the modified compact tension test results: Evaluation of the experiments on cylindrical concrete specimens

Czech Academy of Sciences Publication Activity Database

Holušová, T.; Lozano, M.; Canteli, A.; Komárková, T.; Kocáb, D.; Seitl, Stanislav

2015-01-01

Roč. 15, č. 2 (2015) ISSN 1804-4824 Institutional support: RVO:68081723 Keywords : Modified compact tension test * fracture parametr * Cementitious composites * Aramis measurement * grips Subject RIV: JL - Materials Fatigue, Friction Mechanics

Psychometric testing of the modified Care Dependency Scale (Neuro-CDS).

Science.gov (United States)

Piredda, Michela; Biagioli, Valentina; Gambale, Giulia; Porcelli, Elisa; Barbaranelli, Claudio; Palese, Alvisa; De Marinis, Maria Grazia

2016-01-01

Effective measures of nursing care dependency in neurorehabilitation are warranted to plan nursing interventions to help patients avoid increasing dependency. The Care Dependency Scale (CDS) is a theory-based, comprehensive tool to evaluate functional disability. This study aimed to modify the CDS for neurological and neurorehabilitation patients (Neuro-CDS) and to test its psychometric properties in adult neurorehabilitation inpatients. Exploratory factor analysis (EFA) was performed using a Maximum Likelihood robust (MLR) estimator. The Barthel Index (BI) was used to evaluate concurrent validity. Stability was measured using the Intra-class Correlation Coefficient (ICC). The sample included 124 patients (mean age = 69.7 years, 54% male). The EFA revealed a two-factor structure with good fit indexes, Factor 1 (Physical care dependence) loaded by 11 items and Factor 2 (Psycho-social care dependence) loaded by 4 items. The correlation between factors was 0.61. Correlations between Factor 1 and the BI and between Factor 2 and the BI were r = 0.843 and r = 0.677, respectively (p dependence in neurorehabilitation patients as a basis for individualized and holistic care.

[Determination of plasma protein binding rate of arctiin and arctigenin with ultrafiltration].

Science.gov (United States)

Han, Xue-Ying; Wang, Wei; Tan, Ri-Qiu; Dou, De-Qiang

2013-02-01

To determine the plasma protein binding rate of arctiin and arctigenin. The ultrafiltration combined with HPLC was employed to determine the plasma protein binding rate of arctiin and arctigenin as well as rat plasma and healthy human plasma proteins. The plasma protein binding rate of arctiin with rat plasma at the concentrations of 64. 29, 32.14, 16.07 mg x L(-1) were (71.2 +/- 2.0)%, (73.4 +/- 0.61)%, (78.2 +/- 1.9)%, respectively; while the plasma protein binding rate of arctiin with healthy human plasma at the above concentrations were (64.8 +/- 3.1)%, (64.5 +/- 2.5)%, (77.5 +/- 1.7)%, respectively. The plasma protein binding rate of arctigenin with rat plasma at the concentrations of 77.42, 38.71, 19.36 mg x L(-1) were (96.7 +/- 0.41)%, (96.8 +/- 1.6)%, (97.3 +/- 0.46)%, respectively; while the plasma protein binding rate of arctigenin with normal human plasma at the above concentrations were (94.7 +/- 3.1)%, (96.8 +/- 1.6)%, (97.9 +/- 1.3)%, respectively. The binding rate of arctiin with rat plasma protein was moderate, which is slightly higher than the binding rate of arctiin with healthy human plasma protein. The plasma protein binding rates of arctigenin with both rat plasma and healthy human plasma are very high.

Seawater ultrafiltration fouling control: Backwashing with demineralized water/SWRO permeate

KAUST Repository

Li, Sheng; Heijman, Sebastiaan G J; Verberk, J. Q J C; Amy, Gary L.; Van Dijk, Johannis C.

2012-01-01

In this study, the effect of demineralized water backwashing on fouling control of seawater ultrafiltration was investigated. Seawater from Scheveningen beach in The Hague and a desalination plant of Evides Company at Zeeland in the Netherlands was used as feed water, while demineralized water and UF permeate were used as backwash water for a fouling control efficiency comparison under different fluxes and backwash durations. Furthermore, demineralized waters with 5 or 50 mmol/l NaCl were applied for backwashing as well, to check the influence of monovalent cations on UF fouling control. Additionally, SWRO permeate was used for backwashes in long-term experiments to check the possibility of it replacing demineralized water. Results show that seawater UF fouling control is substantially improved by demineralized water backwashing. However, due to the high salinity of seawater, more water was required to dilute the cation concentration and limit the dispersion effect near the membrane surface than was needed for surface water. A 2-min demineralized water backwash showed better fouling control efficiency than a 1-min backwash. Furthermore, the presence of monovalent cations in the backwash water deteriorated the fouling control efficiency of the backwash, indicating the existence of a charge screening effect. The demineralized water with 5 and 50 mmol/l NaCl both showed a similar fouling control efficiency which is better than the UF permeate backwash. The calcium ions in UF permeate probably deteriorates the fouling control efficiency by maintaining a Ca-bridging effect between the membranes and NOM. SWRO permeate backwashing successfully controls membrane fouling as well. © 2012 Elsevier B.V. All rights reserved.

Seawater ultrafiltration fouling control: Backwashing with demineralized water/SWRO permeate

KAUST Repository

Li, Sheng

2012-09-01

In this study, the effect of demineralized water backwashing on fouling control of seawater ultrafiltration was investigated. Seawater from Scheveningen beach in The Hague and a desalination plant of Evides Company at Zeeland in the Netherlands was used as feed water, while demineralized water and UF permeate were used as backwash water for a fouling control efficiency comparison under different fluxes and backwash durations. Furthermore, demineralized waters with 5 or 50 mmol/l NaCl were applied for backwashing as well, to check the influence of monovalent cations on UF fouling control. Additionally, SWRO permeate was used for backwashes in long-term experiments to check the possibility of it replacing demineralized water. Results show that seawater UF fouling control is substantially improved by demineralized water backwashing. However, due to the high salinity of seawater, more water was required to dilute the cation concentration and limit the dispersion effect near the membrane surface than was needed for surface water. A 2-min demineralized water backwash showed better fouling control efficiency than a 1-min backwash. Furthermore, the presence of monovalent cations in the backwash water deteriorated the fouling control efficiency of the backwash, indicating the existence of a charge screening effect. The demineralized water with 5 and 50 mmol/l NaCl both showed a similar fouling control efficiency which is better than the UF permeate backwash. The calcium ions in UF permeate probably deteriorates the fouling control efficiency by maintaining a Ca-bridging effect between the membranes and NOM. SWRO permeate backwashing successfully controls membrane fouling as well. © 2012 Elsevier B.V. All rights reserved.

The Application of a Modified d-ROMs Test for Measurement of Oxidative Stress and Oxidized High-Density Lipoprotein

Directory of Open Access Journals (Sweden)

Fumiaki Ito

2017-02-01

Full Text Available Reactive oxygen species (ROS are involved in the initiation and progression of atherosclerosis. ROS-derived hydroperoxides, as an indicator of ROS production, have been measured by using the diacron reactive oxygen metabolites (d-ROMs test, which requires iron-containing transferrin in the reaction mixture. In this study we developed a modified d-ROMs test, termed the Fe-ROMs test, where iron ions were exogenously added to the reaction mixture. This modification is expected to exclude the assay variation that comes from different blood iron levels in individuals. In addition, this Fe-ROMs test was helpful for determining the class of plasma lipoproteins that are hydroperoxidized. Low-density lipoprotein/very low-density lipoprotein (LDL/VLDL and high-density lipoprotein (HDL were purified by use of an LDL/VLDL purification kit and the dextran sulfate-Mg2+ precipitation method, respectively; their hydroperoxide contents were assessed by performing the Fe-ROMs test. The majority of the hydroperoxides were detected only in the HDL fraction, not in the LDL/VLDL. Further detailed analysis of HDLs by size-exclusion high-performance liquid chromatography revealed that the hydroperoxide-containing molecules were small-sized HDLs. Because HDL was shown to be the principal vehicle for the plasma hydroperoxides, this Fe-ROMs test is a beneficial method for the assessment of oxidized-HDL levels. Indeed, Fe-ROMs levels were strongly associated with the levels of oxidized HDL, which were determined by performing the malondialdehyde-modified HDL enzyme immunoassay. In conclusion, the Fe-ROMs test using plasma itself or the HDL fraction after dextran sulfate-Mg2+ precipitation is useful to assess the functionality of HDL, because the oxidation of HDL impairs its antiatherogenic capacity.

A Modified Generalized Fisher Method for Combining Probabilities from Dependent Tests

Directory of Open Access Journals (Sweden)

Hongying (Daisy eDai

2014-02-01

Full Text Available Rapid developments in molecular technology have yielded a large amount of high throughput genetic data to understand the mechanism for complex traits. The increase of genetic variants requires hundreds and thousands of statistical tests to be performed simultaneously in analysis, which poses a challenge to control the overall Type I error rate. Combining p-values from multiple hypothesis testing has shown promise for aggregating effects in high-dimensional genetic data analysis. Several p-value combining methods have been developed and applied to genetic data; see [Dai, et al. 2012b] for a comprehensive review. However, there is a lack of investigations conducted for dependent genetic data, especially for weighted p-value combining methods. Single nucleotide polymorphisms (SNPs are often correlated due to linkage disequilibrium. Other genetic data, including variants from next generation sequencing, gene expression levels measured by microarray, protein and DNA methylation data, etc. also contain complex correlation structures. Ignoring correlation structures among genetic variants may lead to severe inflation of Type I error rates for omnibus testing of p-values. In this work, we propose modifications to the Lancaster procedure by taking the correlation structure among p-values into account. The weight function in the Lancaster procedure allows meaningful biological information to be incorporated into the statistical analysis, which can increase the power of the statistical testing and/or remove the bias in the process. Extensive empirical assessments demonstrate that the modified Lancaster procedure largely reduces the Type I error rates due to correlation among p-values, and retains considerable power to detect signals among p-values. We applied our method to reassess published renal transplant data, and identified a novel association between B cell pathways and allograft tolerance.

Computer-based testing of the modified essay question: the Singapore experience.

Science.gov (United States)

Lim, Erle Chuen-Hian; Seet, Raymond Chee-Seong; Oh, Vernon M S; Chia, Boon-Lock; Aw, Marion; Quak, Seng-Hock; Ong, Benjamin K C

2007-11-01

The modified essay question (MEQ), featuring an evolving case scenario, tests a candidate's problem-solving and reasoning ability, rather than mere factual recall. Although it is traditionally conducted as a pen-and-paper examination, our university has run the MEQ using computer-based testing (CBT) since 2003. We describe our experience with running the MEQ examination using the IVLE, or integrated virtual learning environment (https://ivle.nus.edu.sg), provide a blueprint for universities intending to conduct computer-based testing of the MEQ, and detail how our MEQ examination has evolved since its inception. An MEQ committee, comprising specialists in key disciplines from the departments of Medicine and Paediatrics, was formed. We utilized the IVLE, developed for our university in 1998, as the online platform on which we ran the MEQ. We calculated the number of man-hours (academic and support staff) required to run the MEQ examination, using either a computer-based or pen-and-paper format. With the support of our university's information technology (IT) specialists, we have successfully run the MEQ examination online, twice a year, since 2003. Initially, we conducted the examination with short-answer questions only, but have since expanded the MEQ examination to include multiple-choice and extended matching questions. A total of 1268 man-hours was spent in preparing for, and running, the MEQ examination using CBT, compared to 236.5 man-hours to run it using a pen-and-paper format. Despite being more labour-intensive, our students and staff prefer CBT to the pen-and-paper format. The MEQ can be conducted using a computer-based testing scenario, which offers several advantages over a pen-and-paper format. We hope to increase the number of questions and incorporate audio and video files, featuring clinical vignettes, to the MEQ examination in the near future.

Antioxidant activities of bambara groundnut (Vigna subterranea) protein hydrolysates and their membrane ultrafiltration fractions.

Science.gov (United States)

Arise, Abimbola K; Alashi, Adeola M; Nwachukwu, Ifeanyi D; Ijabadeniyi, Oluwatosin A; Aluko, Rotimi E; Amonsou, Eric O

2016-05-18

In this study, the bambara protein isolate (BPI) was digested with three proteases (alcalase, trypsin and pepsin), to produce bambara protein hydrolysates (BPHs). These hydrolysates were passed through ultrafiltration membranes to obtain peptide fractions of different sizes (fractions were investigated for antioxidant activities. The membrane fractions showed that peptides with sizes 3 kDa. This is in agreement with the result obtained for the ferric reducing power, metal chelating and hydroxyl radical scavenging activities where higher molecular weight peptides exhibited better activity (p fractions. However, for all the hydrolysates, the low molecular weight peptides were more effective diphenyl-1-picrylhydrazyl (DPPH) radical scavengers but not superoxide radicals when compared to the bigger peptides. In comparison with glutathione (GSH), BPHs and their membrane fractions had better (p fractions that did not show any metal chelating activity. However, the 5-10 kDa pepsin hydrolysate peptide fractions had greater (88%) hydroxyl scavenging activity than GSH, alcalase and trypsin hydrolysates (82%). These findings show the potential use of BPHs and their peptide fraction as antioxidants in reducing food spoilage or management of oxidative stress-related metabolic disorders.

Characterizing Corrosion Effects of Weak Organic Acids Using a Modified Bono Test

Science.gov (United States)

Zhou, Yuqin; Turbini, Laura J.; Ramjattan, Deepchand; Christian, Bev; Pritzker, Mark

2013-12-01

To meet environmental requirements and achieve benefits of cost-effective manufacturing, no-clean fluxes (NCFs) or low-solids fluxes have become popular in present electronic manufacturing processes. Weak organic acids (WOAs) as the activation ingredients in NCFs play an important role, especially in the current lead-free and halogen-free soldering technology era. However, no standard or uniform method exists to characterize the corrosion effects of WOAs on actual metallic circuits of printed wiring boards (PWBs). Hence, the development of an effective quantitative test method for evaluating the corrosion effects of WOAs on the PWB's metallic circuits is imperative. In this paper, the modified Bono test, which was developed to quantitatively examine the corrosion properties of flux residues, is used to characterize the corrosion effects of five WOAs (i.e., abietic acid, succinic acid, glutaric acid, adipic acid, and malic acid) on PWB metallic circuits. Experiments were performed under three temperature/humidity conditions (85°C/85% RH, 60°C/93% RH, and 40°C/93% RH) using two WOA solution concentrations. The different corrosion effects among the various WOAs were best reflected in the testing results at 40°C and 60°C. Optical microscopy was used to observe the morphology of the corroded copper tracks, and scanning electron microscopy (SEM) energy-dispersive x-ray (EDX) characterization was performed to determine the dendrite composition.

Testing independence of bivariate interval-censored data using modified Kendall's tau statistic.

Science.gov (United States)

Kim, Yuneung; Lim, Johan; Park, DoHwan

2015-11-01

In this paper, we study a nonparametric procedure to test independence of bivariate interval censored data; for both current status data (case 1 interval-censored data) and case 2 interval-censored data. To do it, we propose a score-based modification of the Kendall's tau statistic for bivariate interval-censored data. Our modification defines the Kendall's tau statistic with expected numbers of concordant and disconcordant pairs of data. The performance of the modified approach is illustrated by simulation studies and application to the AIDS study. We compare our method to alternative approaches such as the two-stage estimation method by Sun et al. (Scandinavian Journal of Statistics, 2006) and the multiple imputation method by Betensky and Finkelstein (Statistics in Medicine, 1999b). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Reliability, sensitivity and validity of the assistant referee intermittent endurance test (ARIET) - a modified Yo-Yo IE2 test for elite soccer assistant referees

DEFF Research Database (Denmark)

Castagna, Carlo; Bendiksen, Mads; Impellizzeri, Franco M

2012-01-01

We examined the reliability and validity of the assistant referee intermittent endurance test (ARIET), a modified Yo-Yo IE2 test including shuttles of sideways running. The ARIET was carried out on 198 Italian (Serie A-B, Lega-Pro and National Level) and 47 Danish elite soccer assistant referees....... Reproducibility was tested for 41 assistant referees on four occasions each separated by one week. The ARIET intraclass correlation coefficients and typical error of measurement ranged from 0.96 to 0.99 and 3.1 to 5.7%, respectively. ARIET performance for Serie A and B was 23 and 25% greater than in Lega-Pro (P...... ARIET performance was significantly correlated with VO(2max) (r = 0.78, P ARIET (r = - 0.81, P

Oxyanion flux characterization using passive flux meters: Development and field testing of surfactant-modified granular activated carbon

Science.gov (United States)

Lee, Jimi; Rao, P. S. C.; Poyer, Irene C.; Toole, Robyn M.; Annable, M. D.; Hatfield, K.

2007-07-01

We report here on the extension of Passive Flux Meter (PFM) applications for measuring fluxes of oxyanions in groundwater, and present results for laboratory and field studies. Granular activated carbon, with and without impregnated silver (GAC and SI-GAC, respectively), was modified with a cationic surfactant, hexadecyltrimethylammonium (HDTMA), to enhance the anion exchange capacity (AEC). Langmuir isotherm sorption maxima for oxyanions measured in batch experiments were in the following order: perchlorate >> chromate > selenate, consistent with their selectivity. Linear sorption isotherms for several alcohols suggest that surfactant modification of GAC and SI-GAC reduced (˜ 30-45%) sorption of alcohols by GAC. Water and oxyanion fluxes (perchlorate and chromate) measured by deploying PFMs packed with surfactant-modified GAC (SM-GAC) or surfactant-modified, silver-impregnated GAC (SM-SI-GAC) in laboratory flow chambers were in close agreement with the imposed fluxes. The use of SM-SI-GAC as a PFM sorbent was evaluated at a field site with perchlorate contamination of a shallow unconfined aquifer. PFMs packed with SM-SI-GAC were deployed in three existing monitoring wells with a perchlorate concentration range of ˜ 2.5 to 190 mg/L. PFM-measured, depth-averaged, groundwater fluxes ranged from 1.8 to 7.6 cm/day, while depth-averaged perchlorate fluxes varied from 0.22 to 1.7 g/m 2/day. Groundwater and perchlorate flux distributions measured in two PFM deployments closely matched each other. Depth-averaged Darcy fluxes measured with PFMs were in line with an estimate from a borehole dilution test, but much smaller than those based on hydraulic conductivity and head gradients; this is likely due to flow divergence caused by well-screen clogging. Flux-averaged perchlorate concentrations measured with PFM deployments matched concentrations in groundwater samples taken from one well, but not in two other wells, pointing to the need for additional field testing. Use of

High temperature tensile testing of modified 9Cr-1Mo after irradiation with high energy protons

International Nuclear Information System (INIS)

Toloczko, M.B.; Hamilton, M.L.; Maloy, S.A.

2003-01-01

This study examines the effect of tensile test temperatures ranging from 50 to 600 deg. C on the tensile properties of a modified 9Cr-1Mo ferritic steel after high energy proton irradiation at about 35-67 deg. C to doses from 1 to 3 dpa and 9 dpa. For the specimens irradiated to doses between 1 and 3 dpa, it was observed that the yield strength and ultimate strength decreased monotonically as a function of tensile test temperature, whereas the uniform elongation (UE) remained at approximately 1% for tensile test temperatures up to 250 deg. C and then increased for tensile test temperatures up to and including 500 deg. C. At 600 deg. C, the UE was observed to be less than the values at 400 and 500 deg. C. UE of the irradiated material tensile tested at 400-600 deg. C was observed to be greater than the values for the unirradiated material at the same temperatures. Tensile tests on the 9 dpa specimens followed similar trends

Modified blank ammunition injuries.

Science.gov (United States)

Ogunc, Gokhan I; Ozer, M Tahir; Coskun, Kagan; Uzar, Ali Ihsan

2009-12-15

Blank firing weapons are designed only for discharging blank ammunition cartridges. Because they are cost-effective, are easily accessible and can be modified to live firearms plus their unclear legal situation in Turkish Law makes them very popular in Turkey. 2004 through 2008, a total of 1115 modified blank weapons were seized in Turkey. Blank firing weapons are easily modified by owners, making them suitable for discharging live firearm ammunition or modified blank ammunitions. Two common methods are used for modification of blank weapons. After the modification, these weapons can discharge the live ammunition. However, due to compositional durability problems with these types of weapons; the main trend is to use the modified blank ammunitions rather than live firearm ammunition fired from modified blank firing weapons. In this study, two types of modified blank weapons and two types of modified blank cartridges were tested on three different target models. Each of the models' shooting side was coated with 1.3+/-2 mm thickness chrome tanned cowhide as a skin simulant. The first model was only coated with skin simulant. The second model was coated with skin simulant and 100% cotton police shirt. The third model was coated with skin simulant and jean denim. After the literature evaluation four high risky anatomic locations (the neck area; the eyes; the thorax area and inguinal area) were pointed out for the steel and lead projectiles are discharged from the modified blank weapons especially in close range (0-50 cm). The target models were designed for these anatomic locations. For the target models six Transparent Ballistic Candle blocks (TCB) were prepared and divided into two test groups. The first group tests were performed with lead projectiles and second group with steel projectile. The shortest penetration depth (lead projectile: 4.358 cm; steel projectile 8.032 cm) was recorded in the skin simulant and jean denim coated block for both groups. In both groups

Modifying the IAT to test the relationship between Actual Implicit Self Esteem and depression - A preliminary analysis

Directory of Open Access Journals (Sweden)

Nastasia Sălăgean

2017-06-01

Full Text Available This paper sought to test weather modifying the Implicit Association Test (IAT to contextualize it would better predict depressive symptoms, compared to the classical IAT. Additionally, we explored how both versions of the IAT interact with explicit measures of self-esteem. Using a total of 99 university students (75.75% female, we collected measures of implicit self-esteem (IAT; Greenwald, McGhee, & Schwartz, 1998, actual implicit self-esteem (modified IAT, explicit self-esteem (ESE; Rosenberg,1965, and depression (Spitzer et al, 1999. The same data was collected again after 2 weeks. After employing several hierarchical stepwise regression analyses, results show that the only valid predictor for depression is ESE, with both IAT measurements failing to provide significant results. However, a significant relationship between depression at Time 1 were associated with both standard ISE at Time 2 (r=- 0.24, p<.05 and actual ISE at Time 2 (r=- 0.28, p<.05. No interaction effects were found between either IAT measure and ESE in predicting self-esteem. Moreover, no significant correlations were found between either type of ISE and ESE. The implications of the study are discussed.

Performance Testing Of A Modified Centrifugal Fan With Serrated Blade Impeller

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Zaimar

2017-10-01

Full Text Available Changes of shape dimension and component part of impeller might change of characteristic fluid flow so that pressure static in the fan housing changed. Changing some geometric characteristics of the centrifugal fan has more efficiency taking with energy crises into consideration. Several factors that can affect fan performance namely design and type size rotation speed air condition or gas through a fan operating point on the nature of the relationship between a volume of air flow and pressure. The purpose of this research was to test of fan performance of the modified centrifugal fan with the serrated blade impeller. The addition of a percentage of closing the inlet causes the air volumetric rate the airflow energy BHP and total efficiency except for the fan total and static pressure. The experimental test results there are static pressure data and the resulting total pressure is different or distorted 10-17 of deviation from calculation data based on the fan laws. This is possible because of changes in the shape of the blade with serrated on the inside of the impeller. Based on the performance curve shows that the selection of impeller speeds of 800 RPM produces a relatively high air volumetric rate is proportional to the total pressure of the fan and the flow energy so that it is more efficient than other impeller speeds.

Modified bathroom scale and balance assessment: a comparison with clinical tests.

Science.gov (United States)

Duchêne, Jacques; Hewson, David; Rumeau, Pierre

2016-01-01

Frailty and detection of fall risk are major issues in preventive gerontology. A simple tool frequently used in daily life, a bathroom scale (balance quality tester: BQT), was modified to obtain information on the balance of 84 outpatients consulting at a geriatric clinic. The results computed from the BQT were compared to the values of three geriatric tests that are widely used either to detect a fall risk or frailty (timed get up and go: TUG; 10 m walking speed: WS; walking time: WT; one-leg stand: OS). The BQT calculates four parameters that are then scored and weighted, thus creating an overall indicator of balance quality. Raw data, partial scores and the global score were compared with the results of the three geriatric tests. The WT values had the highest correlation with BQT raw data (r = 0.55), while TUG (r = 0.53) and WS (r = 0.56) had the highest correlation with BQT partial scores. ROC curves for OS cut-off values (4 and 5 s) were produced, with the best results obtained for a 5 s cut-off, both with the partial scores combined using Fisher's combination (specificity 85 %: 0.48), and with the empirical score (specificity 85 %: 8). A BQT empirical score of less than seven can detect fall risk in a community dwelling population.

A Modified Reading the Mind in the Eyes Test Predicts Behavioral Variant Frontotemporal Dementia Better Than Executive Function Tests

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Matthias L. Schroeter

2018-01-01

Full Text Available Behavioral variant frontotemporal dementia (bvFTD is characterized by deep alterations in behavior and personality. Although revised diagnostic criteria agree for executive dysfunction as most characteristic, impairments in social cognition are also suggested. The study aimed at identifying those neuropsychological and behavioral parameters best discriminating between bvFTD and healthy controls. Eighty six patients were diagnosed with possible or probable bvFTD according to Rascovsky et al. (2011 and compared with 43 healthy age-matched controls. Neuropsychological performance was assessed with a modified Reading the Mind in the Eyes Test (RMET, Stroop task, Trail Making Test (TMT, Hamasch-Five-Point Test (H5PT, and semantic and phonemic verbal fluency tasks. Behavior was assessed with the Apathy Evaluation Scale, Frontal Systems Behavioral Scale, and Bayer Activities of Daily Living Scale. Each test’s discriminatory power was investigated by Receiver Operating Characteristic curves calculating the area under the curve (AUC. bvFTD patients performed significantly worse than healthy controls in all neuropsychological tests. Discriminatory power (AUC was highest in behavioral questionnaires, high in verbal fluency tasks and the RMET, and lower in executive function tests such as the Stroop task, TMT and H5PT. As fluency tasks depend on several cognitive functions, not only executive functions, results suggest that the RMET discriminated better between bvFTD and control subjects than other executive tests. Social cognition should be incorporated into diagnostic criteria for bvFTD in the future, such as in the International Classification of Diseases (ICD-11, as already suggested in the Diagnostic and Statistical Manual for Mental Disorders (DSM-5.

Flux dependency of particulate/colloidal fouling in seawater reverse osmosis systems

KAUST Repository

Salinas Rodríguez, S. G.

2012-01-01

Fouling is the main operational problem in seawater reverse osmosis systems (SWRO). Particulate fouling is traditionally measured through the silt density index (SDI) and through the modified fouling index (MFI). In recent years, ultrafiltration membranes were used successfully at constant flux-MFI-UF-to measure particulate/colloidal fouling potential and tested in sea water applications. Furthermore, constant flux operation allows predicting the rate of fouling in RO systems. The objectives of this study are: (1) to measure the flux effect in MFI-UF with different membranes (100, 30 and 10 kDa) for raw seawater and pre-treated water before reverse osmosis in three different locations; (2) to study the particulate and colloidal fouling potential of seawater in reverse osmosis systems; (3) to project the increase in pressure due to cake resistance in reverse osmosis systems. In this research, flat ultrafiltration membranes (100, 50, 30 and 10 kDa) are used in a con- stant flux filtration mode to test and compare real seawaters from various locations (North and Mediterranean Sea) and from various full scale facilities including different pre-treatments (i.e., ultrafiltration and coagulation + dual media filtration). The operated fluxes range from 350 down to values close to real RO operation, 15l(m2h)-1. After each filtration test, the MFI-UF is calculated to assess the particulate fouling potential. The obtained results showed that: (1) the particulate and colloidal fouling potential is directly proportional to the applied flux during filtration. This proportionality is related to the compression of the cake deposit occurring at high flux values; (2) the higher the flux, the higher the required pressure, the less porous the cake and therefore the higher the specific cake resistance; (3) particulate and colloidal fouling potential of seawater is site specific and is influenced by pre-treatment. © 2012 Desalination Publications. All rights reserved.

46 CFR 57.04-1 - Test specimen requirements and definition of ranges (modifies QW 202, QW 210, QW 451, and QB 202).

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Test specimen requirements and definition of ranges... HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING WELDING AND BRAZING Procedure Qualification Range § 57.04-1 Test specimen requirements and definition of ranges (modifies QW 202, QW 210, QW 451, and QB 202...

Modified SPC for short run test and measurement process in multi-stations

Science.gov (United States)

Koh, C. K.; Chin, J. F.; Kamaruddin, S.

2018-03-01

Due to short production runs and measurement error inherent in electronic test and measurement (T&M) processes, continuous quality monitoring through real-time statistical process control (SPC) is challenging. Industry practice allows the installation of guard band using measurement uncertainty to reduce the width of acceptance limit, as an indirect way to compensate the measurement errors. This paper presents a new SPC model combining modified guard band and control charts (\\bar{\\text{Z}} chart and W chart) for short runs in T&M process in multi-stations. The proposed model standardizes the observed value with measurement target (T) and rationed measurement uncertainty (U). S-factor (S f) is introduced to the control limits to improve the sensitivity in detecting small shifts. The model was embedded in automated quality control system and verified with a case study in real industry.

A numerical study of two different specimen fixtures for the modified compact tension test – their influence on concrete fracture parameters

Czech Academy of Sciences Publication Activity Database

Holušová, Táňa; Seitl, Stanislav; Cifuentes, H.; Canteli, A.

2016-01-01

Roč. 10, č. 35 (2016), s. 242-249 ISSN 1971-8993 Institutional support: RVO:68081723 Keywords : Modified Compact Tension Test * Fracture Parameters * Cementitious Composites * FEM Subject RIV: JL - Materials Fatigue, Friction Mechanics

Modified whole effluent toxicity test to assess and decouple wastewater effects from environmental gradients.

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Sebastián Sauco

Full Text Available Environmental gradients and wastewater discharges produce aggregated effects on marine populations, obscuring the detection of human impact. Classical assessment methods do not include environmental effects in toxicity tests designs, which could lead to incorrect conclusions. We proposed a modified Whole Effluent Toxicity test (mWET that includes environmental gradients in addition to effluent dilutions, together with the application of Generalized Linear Mixed Models (GLMM to assess and decouple those effects. We tested this approach, analyzing the lethal effects of wastewater on a marine sandy beach bivalve affected by an artificial canal freshwater discharge used for rice crops irrigation. To this end, we compared bivalve mortality between canal water dilutions (CWd and salinity controls (SC: without canal water. CWd were prepared by diluting the water effluent (sampled during the pesticide application period with artificial marine water. The salinity gradient was included in the design by achieving the same final salinities in both CWd and SC, allowing us to account for the effects of salinity by including this variable as a random factor in the GLMM. Our approach detected significantly higher mortalities in CWd, indicating potential toxic effects of the effluent discharge. mWET represents an improvement over the internationally standardized WET tests, since it considers environmental variability and uses appropriate statistical analyses.

Synthesis of nanodiamond derivatives carrying amino functions and quantification by a modified Kaiser test

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Gerald Jarre

2014-11-01

Full Text Available Nanodiamonds functionalized with different organic moieties carrying terminal amino groups have been synthesized. These include conjugates generated by Diels–Alder reactions of ortho-quinodimethanes formed in situ from pyrazine and 5,6-dihydrocyclobuta[d]pyrimidine derivatives. For the quantification of primary amino groups a modified photometric assay based on the Kaiser test has been developed and validated for different types of aminated nanodiamond. The results correspond well to values obtained by thermogravimetry. The method represents an alternative wet-chemical quantification method in cases where other techniques like elemental analysis fail due to unfavourable combustion behaviour of the analyte or other impediments.

Development of a High Performance PES Ultrafiltration Hollow Fiber Membrane for Oily Wastewater Treatment Using Response Surface Methodology

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Noor Adila Aluwi Shakir

2015-12-01

Full Text Available This study attempts to optimize the spinning process used for fabricating hollow fiber membranes using the response surface methodology (RSM. The spinning factors considered for the experimental design are the dope extrusion rate (DER, air gap length (AGL, coagulation bath temperature (CBT, bore fluid ratio (BFR, and post-treatment time (PT whilst the response investigated is rejection. The optimal spinning conditions promising the high rejection performance of polyethersulfone (PES ultrafiltration hollow fiber membranes for oily wastewater treatment are at the dope extrusion rate of 2.13 cm3/min, air gap length of 0 cm, coagulation bath temperature of 30 °C, and bore fluid ratio (NMP/H2O of 0.01/99.99 wt %. This study will ultimately enable the membrane fabricators to produce high-performance membranes that contribute towards the availability of a more sustainable water supply system.

Uranium aqueous speciation in the vicinity of the former uranium mining sites using the diffusive gradients in thin films and ultrafiltration techniques.

Science.gov (United States)

Drozdzak, Jagoda; Leermakers, Martine; Gao, Yue; Elskens, Marc; Phrommavanh, Vannapha; Descostes, Michael

2016-03-24

The performance of the Diffusive Gradients in Thin films (DGT) technique with Chelex(®)-100, Metsorb™ and Diphonix(®) as binding phases was evaluated in the vicinity of the former uranium mining sites of Chardon and L'Ecarpière (Loire-Atlantique department in western France). This is the first time that the DGT technique with three different binding agents was employed for the aqueous U determination in the context of uranium mining environments. The fractionation and speciation of uranium were investigated using a multi-methodological approach using filtration (0.45 μm, 0.2 μm), ultrafiltration (500 kDa, 100 kDa and 10 kDa) coupled to geochemical speciation modelling (PhreeQC) and the DGT technique. The ultrafiltration data showed that at each sampling point uranium was present mostly in the 10 kDa truly dissolved fraction and the geochemical modelling speciation calculations indicated that U speciation was markedly predominated by CaUO2(CO3)3(2-). In natural waters, no significant difference was observed in terms of U uptake between Chelex(®)-100 and Metsorb™, while similar or inferior U uptake was observed on Diphonix(®) resin. In turn, at mining influenced sampling spots, the U accumulation on DGT-Diphonix(®) was higher than on DGT-Chelex(®)-100 and DGT-Metsorb™, probably because their performance was disturbed by the extreme composition of the mining waters. The use of Diphonix(®) resin leads to a significant advance in the application and development of the DGT technique for determination of U in mining influenced environments. This investigation demonstrated that such multi-technique approach provides a better picture of U speciation and enables to assess more accurately the potentially bioavailable U pool. Copyright © 2016 Elsevier B.V. All rights reserved.

Peritoneal fluid transport in CAPD patients with different transport rates of small solutes.

Science.gov (United States)

Sobiecka, Danuta; Waniewski, Jacek; Weryński, Andrzej; Lindholm, Bengt

2004-01-01

Continuous ambulatory peritoneal dialysis (CAPD) patients with high peritoneal solute transport rate often have inadequate peritoneal fluid transport. It is not known whether this inadequate fluid transport is due solely to a too rapid fall of osmotic pressure, or if the decreased effectiveness of fluid transport is also a contributing factor. To analyze fluid transport parameters and the effectiveness of dialysis fluid osmotic pressure in the induction of fluid flow in CAPD patients with different small solute transport rates. 44 CAPD patients were placed in low (n = 6), low-average (n = 13), high-average (n = 19), and high (n = 6) transport groups according to a modified peritoneal equilibration test (PET). The study involved a 6-hour peritoneal dialysis dwell with 2 L 3.86% glucose dialysis fluid for each patient. Radioisotopically labeled serum albumin was added as a volume marker.The fluid transport parameters (osmotic conductance and fluid absorption rate) were estimated using three mathematical models of fluid transport: (1) Pyle model (model P), which describes ultrafiltration rate as an exponential function of time; (2) model OS, which is based on the linear relationship of ultrafiltration rate and overall osmolality gradient between dialysis fluid and blood; and (3) model G, which is based on the linear relationship between ultrafiltration rate and glucose concentration gradient between dialysis fluid and blood. Diffusive mass transport coefficients (K(BD)) for glucose, urea, creatinine, potassium, and sodium were estimated using the modified Babb-Randerson-Farrell model. The high transport group had significantly lower dialysate volume and glucose and osmolality gradients between dialysate and blood, but significantly higher K(BD) for small solutes compared with the other transport groups. Osmotic conductance, fluid absorption rate, and initial ultrafiltration rate did not differ among the transport groups for model OS and model P. Model G yielded

Postirradiation notch ductility tests of ESR alloy HT-9 and modified 9Cr-1Mo alloy from UBR reactor experiments

International Nuclear Information System (INIS)

Hawthorne, J.R.

1984-01-01

During this period, irradiation exposures at 300 0 C and 150 0 C to approx. 8 x 10 19 n/cm 2 , E > 0.1 MeV, were completed for the Alloy HT-9 plate and the modified Alloy 9Cr-1Mo plates, respectively. Postirradiation tests of Charpy-V (C/sub v/) specimens were completed for both alloys; other specimen types included in the reactor assemblies were fatigue precracked Charpy-V (PCC/sub v/), half-size Charpy-V, and in the case of the modified 9Cr-1Mo, 2.54 mm thick compact tension specimens

Improving the performance of the Egyptian second testing nuclear research reactor using interval type-2 fuzzy logic controller tuned by modified biogeography-based optimization

Energy Technology Data Exchange (ETDEWEB)

Sayed, M.M., E-mail: M.M.Sayed@ieee.org; Saad, M.S.; Emara, H.M.; Abou El-Zahab, E.E.

2013-09-15

Highlights: • A modified version of the BBO was proposed. • A novel method for interval type-2 FLC design tuned by MBBO was proposed. • The performance of the ETRR-2 was improved by using IT2FLC tuned by MBBO. -- Abstract: Power stabilization is a critical issue in nuclear reactors. The conventional proportional derivative (PD) controller is currently used in the Egyptian second testing research reactor (ETRR-2). In this paper, we propose a modified biogeography-based optimization (MBBO) algorithm to design the interval type-2 fuzzy logic controller (IT2FLC) to improve the performance of the Egyptian second testing research reactor (ETRR-2). Biogeography-based optimization (BBO) is a novel evolutionary algorithm that is based on the mathematical models of biogeography. Biogeography is the study of the geographical distribution of biological organisms. In the BBO model, problem solutions are represented as islands, and the sharing of features between solutions is represented as immigration and emigration between the islands. A modified version of the BBO is applied to design the IT2FLC to get the optimal parameters of the membership functions of the controller. We test the optimal IT2FLC obtained by modified biogeography-based optimization (MBBO) using the integral square error (ISE) and is compared with the currently used PD controller.

Performance of ceramic ultrafiltration and reverse osmosis membranes in treating car wash wastewater for reuse.

Science.gov (United States)

Moazzem, Shamima; Wills, Jamie; Fan, Linhua; Roddick, Felicity; Jegatheesan, Veeriah

2018-03-01

Reusing treated effluents in industries is a great option to conserve freshwater resources. For example, car wash centres all over Australia are estimated to use 17.5 billion litres of water and discharge it as wastewater and spend $75 million a year for both purchasing fresh water and for treating and/or discharging the wastewater. Therefore, it is important to develop simple but reliable systems that can help to treat and reuse car wash wastewater. Significant savings could also be associated with the implementation of such systems. This study evaluates the performance of granular and membrane filtration systems with coagulation/flocculation and sedimentation in treating car wash wastewater for the purpose of reuse. Overall, 99.9% of turbidity, 100% of suspended solids and 96% of COD were removed from the car wash wastewater after treating by coagulation, flocculation, sedimentation, sand filtration, ceramic ultrafiltration and reverse osmosis and the treated water meets the standards required for class A recycled water in Australia and standards imposed in Belgium and China. The treated water can be reused. However, optimisation is required to reduce the sludge produced by this system.

Production and functional characterisation of antioxidative hydrolysates from corn protein via enzymatic hydrolysis and ultrafiltration.

Science.gov (United States)

Zhou, Kequan; Sun, Shi; Canning, Corene

2012-12-01

Corn protein was hydrolysed by three microbial proteases and further separated by sequential ultra-filtration to 12 hydrolysate fractions which were investigated for free radical scavenging capacity and chelating activity. The oxygen radical absorbance capacity (ORAC) of the hydrolysates varied significantly between 65.6 and 191.4μmoles Trolox equivalents (TE)/g dried weight with a small peptide fraction (NP-F3) produced by neutral protease (NP) possessing the highest antioxidant activity. The 1,1-diphenyl-2-picrylhydrazyl radical (DPPH()) scavenging activities of the hydrolysate fractions also varied significantly between 18.4 and 38.7μmoles TE/g. Two fractions (AP-F2 and AP-F3) produced by alkaline protease (AP) showed the strongest activity. However, no significant difference was detected on the chelating activity of the fractions. NP-F3, AP-F2, and AP-F3 were incorporated into ground beef to determine their effects on lipid oxidation during 15-day storage period. NP-F3 was the only fraction that inhibited lipid oxidation at both 250 and 500μg/g levels by as much as 52.9%. Copyright © 2012 Elsevier Ltd. All rights reserved.

Studies on preparation of medium fat liquid dairy whitener from buffalo milk employing ultrafiltration process.

Science.gov (United States)

Khatkar, Sunil Kumar; Gupta, Vijay Kumar; Khatkar, Anju Boora

2014-09-01

A study was conducted to develop good quality medium fat liquid dairy whitener from buffalo milk employing ultrafiltration (UF) process. The buffalo skim milk was UF concentrated to 4.05 to 4.18 (23.63 ± 0.30 % TS) fold and standardized to 10 % fat (on Dry Matter Basis) (i.e. formulation) and homogenized at 175.76 kg/cm(2). The addition of 0.4 % mixture of monosodium and disodium phosphate (2:1 w/w) improved the heat stability of homogenized formulation to an optimum of 66 min. The bland flavour of homogenized formulation with added 0.4 % mixture of monosodium phosphate and disodium phosphate (2:1 w/w) and 18 % sugar (on DMB) (i.e. medium fat liquid dairy whitener) was improved significantly (P coffee was significantly (P market dairy whitener samples. At 2 % solids level, standardized medium fat liquid dairy whitener in tea/coffee fetched significantly (P market sample at 3 % solids level. There could be clear 33 % solids quantity saving in case of developed product compared to market dairy whitener sample.

Modified General Relativity and Cosmology

Science.gov (United States)

Abdel-Rahman, A.-M. M.

1997-10-01

Aspects of the modified general relativity theory of Rastall, Al-Rawaf and Taha are discussed in both the radiation- and matter-dominated flat cosmological models. A nucleosynthesis constraint on the theory's free parameter is obtained and the implication for the age of the Universe is discussed. The consistency of the modified matter- dominated model with the neoclassical cosmological tests is demonstrated.

Impact of Modified 2013 ASCO/CAP Guidelines on HER2 Testing in Breast Cancer. One Year Experience.

Directory of Open Access Journals (Sweden)

Zsuzsanna Varga

Full Text Available The latest guidelines of the American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP to test Human Epidermal Growth Factor Receptor 2 (HER2 in breast cancer after being revised in 2008 underwent a second modification in October 2013. The modification includes changes in cut-offs: 10% strong membranous staining for score 3+ on immunohistochemistry (IHC (previously 30% and using the ratio of >2 or absolute gene-copy-number (6 or more alone or in combination with each other by in-situ-hybridisation technology (previously >2.2 and average copy-number of 6 or more. Hereby we addressed the question, which impact the modified cut-offs had on overall HER2-positivity in a single institution.We prospectively analysed 617 consecutive diagnostic breast-cancer cases which underwent double HER2 testing by immunohistochemistry and fluorescent in-situ hybridisation (FISH, using the modified 2013 ASCO/CAP-guidelines for one year (October 2013-October 2014. Results were compared with HER2-test results on 1,528 consecutive diagnostic breast-cancer cases from two previous years (2011-2012, using the 2008 ASCO/CAP guidelines, also tested with IHC and FISH in each case.Between October 2013 and October 2014, overall HER2-positivity was 15.8% (98 of 617 cases were either IHC 3+ or FISH amplified. 79 of 617 cases (13% were IHC 3+, 96 of 617 cases (15.5% were FISH amplified. Equivocal cases were seen in 25 of 617 cases (4.1%. 22 of 25 equivocal cases (88% in 2013-2014 were IHC 1+ or 2+. In 13 equivocal cases, there was a repeated IHC/FISH testing: 2 of 13 cases (15% became FISH amplified, 1 of 13 cases (7.5% became IHC 3+. In 2011-2012, overall HER2-positivity (IHC/FISH was 13.8% (211 of 1,528 cases. 185 of 1,528 cases (12% were 3+ on IHC, 181 of 1,522 cases (12% were amplified by FISH. Six of 1,528 cases were equivocal by FISH, and interpreted as non-amplified (0.3%.Applying the modified ASCO/CAP guidelines from 2013 resulted in an increase (2

Mechanical properties of polymer-modified porous concrete

Science.gov (United States)

Ariffin, N. F.; Jaafar, M. F. Md.; Shukor Lim, N. H. Abdul; Bhutta, M. A. R.; Hussin, M. W.

2018-04-01

In this research work, polymer-modified porous concretes (permeable concretes) using polymer latex and redispersible polymer powder with water-cement ratio of 30 %, polymer-cement ratios of 0 to 10 % and cement content of 300 kg/m3 are prepared. The porous concrete was tested for compressive strength, flexural strength, water permeability and void ratio. The cubes size of specimen is 100 mm ×100 mm × 100 mm and 150 mm × 150 mm × 150 mm while the beam size is 100 mm × 100 mm × 500 mm was prepared for particular tests. The tests results show that the addition of polymer as a binder to porous concrete gives an improvement on the strength properties and coefficient of water permeability of polymer-modified porous concrete. It is concluded from the test results that increase in compressive and flexural strengths and decrease in the coefficient of water permeability of the polymer-modified porous concrete are clearly observed with increasing of polymer-cement ratio.

Postirradiation fracture toughness tests of ESR alloy HT-9 and modified 9Cr-1Mo alloy from UBR reactor experiments

International Nuclear Information System (INIS)

Hawthorne, J.R.; Reed, J.R.; Sprague, J.A.

1984-01-01

Alloy HT-9 and Modified 9Cr-1Mo are being evaluated for potential applications as first wall materials in magnetic fusion reactors. Objectives of the current research task were to test fatigue-precracked Charpy-V (PCC/sub v/) specimens from representative plates irradiated in the UBR reactor at 149 0 C or 300 0 C, and, to compare the results against postirradiation notch ductility data developed previously for the materials. Both plates represent electroslag refined (ESR) melt processing. PCC/sub v/ specimens of Alloy HT-9 and Modified 9Cr-1Mo alloy were irradiated at 300 0 C and 149 0 C, respectively, to approx.0.8 X 10 20 n/cm 2 , E > 0.1 MeV. During this period, postirradiation tests for fracture toughness were completed and results compared to notch ductility determinations from standard Charpy-V (C/sub v/) specimens irradiated in the same reactor experiments. Fracture surface examinations by SEM are also reported

Cross-cultural adaptation and reproducibility of the Brazilian-Portuguese version of the modified FRESNO Test to evaluate the competence in evidence based practice by physical therapists.

Science.gov (United States)

Silva, Anderson M; Costa, Lucíola C M; Comper, Maria L; Padula, Rosimeire S

2016-01-01

The Modified Fresno Test was developed to assess knowledge and skills of both physical therapy (PT) professionals and students to use evidence-based practice (EBP). To translate the Modified Fresno Test into Brazilian-Portuguese and to evaluate the test's reproducibility. The first step consisted of adapting the instrument into the Brazilian-Portuguese language. Then, a total of 57 participants, including PT students, PT professors and PT practitioners, completed the translated instrument. The responses from the participants were used to evaluate reproducibility of the translated instrument. Internal consistency was calculated using the Cronbach's alpha. Reliability was calculated using the intraclass correlation coefficient (ICC) for continuous variables, and the Kappa coefficient (K) for categorical variables. The agreement was assessed using the standard error of the measurement (SEM). The cross-cultural adaptation process was appropriate, providing an adequate Brazilian-Portuguese version of the instrument. The internal consistency was good (α=0.769). The reliability for inter- and intra-rater assessment were ICC=0.89 (95% CI 0.82 to 0.93); for evaluator 1 was ICC=0.85 (95% CI 0.57 to 0.93); and for evaluator 2 was ICC=0.98 (95% CI 0.97 to 0.99). The SEM was 13.04 points for inter-rater assessment, 12.57 points for rater 1 and 4.59 points for rater 2. The Brazilian-Portuguese language version of the Modified Fresno Test showed satisfactory results in terms of reproducibility. The Modified Fresno Test will allow physical therapy professionals and students to be evaluated on the use of understanding EBP.

A modified straight leg raise test to differentiate between sural nerve pathology and Achilles tendinopathy. A cross-sectional cadaver study

NARCIS (Netherlands)

Coppieters, M.W.J.; Crooke, J.L.; Lawrenson, P.R.; Khoo, S.J.; Skulstad, T.; Bet-Or, Y.

2015-01-01

Background: A modified straight leg raise test for the sural nerve (SLRSURAL) has been proposed to assist in the differential diagnosis of sural nerve pathology in people with posterior calf or ankle pain, or lateral foot pain. The biomechanical rationale is that strain in the

Inorganic sorbents for removal of radioactivity from aqueous waste streams: 1. Development of seeded ultrafiltration. 2. Ion exchange properties of hydrous titanium oxide. 3. The novel absorber evaluation club

International Nuclear Information System (INIS)

Hooper, E.W.

1997-01-01

This report describes briefly three areas of work involving inorganic sorbents that have been carried out at AEA Technology, Harwell during the course of the Co-ordinated Research Programme (CRP). 1. Seed ultrafiltration, in which finely divided sodium nickel hexacyanoferrate (II), zirconium phosphate and a hydrous titanium oxide were used as a 'seed' cocktail, in combination with cross-flow membrane filtration, to decontaminate a simulate PWR primary coolant. All but one of the eight radionuclides present were reduced in concentration by a factor of ten or more. 2. Some data on the ion-exchange properties of hydrous titanium oxides are presented. These include the cation exchange capacity for barium (as a stand-in for radium), kinetics of sorption and Na:Ti ratio at different values of pH. 3. Some of the data collected from tests carried out by the Novel Absorber Evaluation Club are presented for a number of sorbents that have been examined during the period of this CRP. (author). 1 ref., 5 figs, 6 tabs

Improved Precision and Efficiency of a Modified ORG0020 Dynamic Respiration Test Setup for Compost Stability Assessment

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Diana Guillen Ferrari

2017-12-01

Full Text Available The ORG0020 dynamic respiration test is effective at distinguishing source segregated organic waste derived composts across a wide range of stabilities when compared to other standard tests; however, using the original diaphragm pump and manifold setup, the test is affected by variability in flow rate with time and across sample replicate vessels. Here, we demonstrate the use of a multichannel peristaltic pump to deliver a more consistent air flow to individual vessels. Using finished and unfinished industry compost samples from different sites with varying stabilities, we provide evidence of greater precision of the modified setup compared to the original. Furthermore, the reduced need for air flow adjustment resulted in improved running cost efficiency with less labour demand. Analysis of compost sample oxygen demand supports the current test air flow rate of 25–75 mL min−1, although the improved air flow control will enable future narrowing of the acceptable range for better inter-laboratory performance.

Analysis of the Modified Smith Predictor

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Jorge A. Herrera-Cuartas

2013-11-01

Full Text Available In this paper an analysis about the modified Smith predictor, is presented. The modified Smith predictor is a scheme used to control stable, unstable and integrative systems. The closed loop equation is developed and analyzed. Additionally, various test are made to verify the behavior of the control scheme. Specify, three test are made. First, it is verify the behavior of the scheme to deal with an uncertainty in the delay model. Second, it is verify the behavior in the face of uncertainties in the parameter of the rational model. 

Brazilian preliminary norms and investigation of age and education effects on the Modified Wisconsin Card Sorting Test, Stroop Color and Word test and Digit Span test in adults

Science.gov (United States)

Zimmermann, Nicolle; Cardoso, Caroline de Oliveira; Trentini, Clarissa Marceli; Grassi-Oliveira, Rodrigo; Fonseca, Rochele Paz

2015-01-01

Executive functions are involved in a series of human neurological and psychiatric disorders. For this reason, appropriate assessment tools with age and education adjusted norms for symptom diagnosis are necessary. Objective To present normative data for adults (19-75 year-olds; with five years of education or more) on the Modified Wisconsin Card Sorting Test (MWCST), Stroop color and word test and Digit Span test. Age and education effects were investigated. Methods Three samples were formed after inclusion criteria and data analysis: MWCST (n=124); Digit Span (n=123), and Stroop test (n=158). Groups were divided into young (19-39), middle-aged (40-59) and older (60-75) participants with five to eight years of education and nine years of education or more. Two-way ANOVA and ANCOVA analyses were used. Results Education effects were found in most variables of the three tasks. An age effect was only found on color naming and color-word naming speed from the Stroop test. No interactions were detected. Conclusion In countries with heterogeneous educational backgrounds, the use of stratified norms by education to assess at least some components of executive functions is essential for an ethical and accurate cognitive diagnosis. PMID:29213953

Introduction to the modified TROI test facility for fuel coolant interaction under a submerged reactor vessel

International Nuclear Information System (INIS)

Na, Young Su; Hong, Seong-Wan; Song, Jin Ho; Hong, Seong-Ho

2014-01-01

The molten Fuel-Coolant Interaction (FCI) can threaten the integrity of the reactor cavity under a severe accident. A steam explosion can be occurred by the rapid energy transfer in the high-temperature corium melt jet penetrating into water, which makes the dynamic load applying to the surrounding structure. Before a steam explosion, the corium melt jet breaks into small-sized particles, and the steam is generated continuously by the film boiling on the hot surface of the melt contacting with water. The premixing phase consisting of the corium melt, water, and steam can determine the intensity of the steam explosion. Unfortunately, the previous experimental studies on the FCI phenomena have carried out under a free fall of the corium melt jet in a gas phase before interacting with water. The previous TROI (Test for Real cOrium Interaction with water) test facility, that is a well-known test facility for the FCI phenomena in the world, has observed a steam explosion under a free fall of a corium melt jet in a gas phase before contacting a coolant since 2000, which is changing to simulate the FCI phenomena under a submerged reactor vessel. This study introduces the modified TROI test facility as shown in Fig. 1 and the considerations for the experiment with success. The previous TROI test facility, that has observed the molten Fuel-Coolant Interaction (FCI) with a free fall of the prototypic corium melt in a gas phase before contacting a coolant, was modified to simulate the FCI phenomena under a submerged reactor vessel for the assessment of the In-Vessel Retention (IVR) concept, i.e., without a free-fall distance of the corium melt before contacting water. The superheated prototypic corium melt created by the cold crucible melting method moves on a releasing valve newly installed just above the water level in the interaction vessel. The corium melt will stay on a releasing valve in less than 0.2 seconds to reduce heat loss for preventing the solidification, and

Teste de TBA aplicado a carnes e derivados: métodos tradicionais, modificados e alternativos TBA test applied to meats and their products: traditional, modified and alternative methods

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Cibele Cristina Osawa

2005-08-01

Full Text Available The TBA test is essential to quality control of fat-containing food, being the test most applied to evaluate lipid peroxidation in fishery, meat and poultry products. It estimates malonaldehyde, a secondary oxidation product, by reacting with 2-thiobarbituric acid, forming a coloured complex, measured spectrophotometrically atlambda = 532 nm. Results are expressed as mg malonaldehyde per kg sample or frequently as "TBA value". There are four ways of quantifying it: by lipid extraction, direct heating, distillation or heat-acid extraction. This review intends to point out traditional, modified and alternative TBA test methods, besides enumerating advantages and drawbacks of each one.

Removal of Cu(II) in water by polymer enhanced ultrafiltration: Influence of polymer nature and pH.

Science.gov (United States)

Kochkodan, Olga D; Kochkodan, Viktor M; Sharma, Virender K

2018-01-02

This study presents an efficient removal of Cu(II) in water using the polymer enhanced ultrafiltration (PEUF) method. Polymer of different molecular weight (MW) (polyethyleneimine (PEI), sodium lignosulfonates (SLS) and dextrans) were investigated to evaluate efficiency in removal of Cu(II) in water by the PEUF method. The decomposition of Cu(II)-polymer complex was also evaluated in order to reuse polymers. Cu(II) complexation depends on the MW of chelating polymer and the pH of feed solution. It was found that the Cu(II) rejection increased with the polymer dosage with high removal of Cu(II) when using PEI and SLS at a 10:20 (mg/mg) ratio ([Cu(II)]:[polymer]). It was found that the maximum chelating capacity was 15 mg of Cu(II) per 20 mg of PEI. The Cu(II)-PEI complex could be decomposed by acid addition and the polymer could be efficiently reused with multiple complexation-decomplexation cycles. A conceptual flow chart of the integrated process of efficient removal of Cu(II) by PEUF method is suggested.

Estudo da validade e confiabilidade intra e interobservador da versão modificada do teste de Schöber modificado em indivíduos com lombalgia Study of validity and intra and inter-observer reliability of modified-modified Schöber test in subjects with low-back pain

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Christiane de Souza Guerino Macedo

2009-09-01

Full Text Available Em pacientes com lombalgia, mensura-se a amplitude de movimento (ADM da coluna lombar por meio da versão modificada do teste de Schöber modificado (MTSM, mas suas propriedades psicométricas não são comprovadas para uso clínico. Este estudo verificou a validade e confiabilidade intra e interobservador do MTSM em indivíduos com lombalgia, comparando as medidas da ADM com as obtidas por meio de radiografia, método considerado padrão-ouro. Participaram 20 voluntários com lombalgia, de ambos os sexos, funcionários de um Hospital Universitário. O MTSM foi aplicado duas vezes por dois avaliadores. As medidas obtidas pelo teste e por radiografia foram comparadas usando o coeficiente de correlação de Pearson, obtendo-se r=0,14, ou seja, correlação fraca. O coeficiente de correlação intraclasse (CCI dos MTSM intra-observador foi 0,96 (IC 95% 0,91;0,98 e interobservador 0,93 (IC 95% 0,84;0,97, indicando alta confiabilidade; o teste de Bland & Altman mostrou alta concordância intra e interobservador, com valores de -0,21 e -0,28, respectivamente. Embora tenha sido encontrada alta confiabilidade intra e interobservador na aplicação da versão modificada do teste de Schöber modificado, este apresentou baixa validade para medir a ADM da coluna lombar, quando comparado ao padrão-ouro.In patients with low-back pain the lumbar spine range of motion (ROM is often measured by the modified version of the modified Schöber test (MMST, but its psychometric properties have not been ascertained for clinical use. The purpose here was to verify intra and inter-observer validity and reliability of the MMST in subjects with low-back pain, and to compare obtained ROM measures to those obtained by radiography, taken as gold standard. The study involved 20 subjects with chronic low-back pain, of both sexes, employees at a university hospital. The MMST was applied twice by two examiners each. The Pearson correlation coefficient found when comparing

Huntingtin interacting proteins are genetic modifiers of neurodegeneration.

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Linda S Kaltenbach

2007-05-01

Full Text Available Huntington's disease (HD is a fatal neurodegenerative condition caused by expansion of the polyglutamine tract in the huntingtin (Htt protein. Neuronal toxicity in HD is thought to be, at least in part, a consequence of protein interactions involving mutant Htt. We therefore hypothesized that genetic modifiers of HD neurodegeneration should be enriched among Htt protein interactors. To test this idea, we identified a comprehensive set of Htt interactors using two complementary approaches: high-throughput yeast two-hybrid screening and affinity pull down followed by mass spectrometry. This effort led to the identification of 234 high-confidence Htt-associated proteins, 104 of which were found with the yeast method and 130 with the pull downs. We then tested an arbitrary set of 60 genes encoding interacting proteins for their ability to behave as genetic modifiers of neurodegeneration in a Drosophila model of HD. This high-content validation assay showed that 27 of 60 orthologs tested were high-confidence genetic modifiers, as modification was observed with more than one allele. The 45% hit rate for genetic modifiers seen among the interactors is an order of magnitude higher than the 1%-4% typically observed in unbiased genetic screens. Genetic modifiers were similarly represented among proteins discovered using yeast two-hybrid and pull-down/mass spectrometry methods, supporting the notion that these complementary technologies are equally useful in identifying biologically relevant proteins. Interacting proteins confirmed as modifiers of the neurodegeneration phenotype represent a diverse array of biological functions, including synaptic transmission, cytoskeletal organization, signal transduction, and transcription. Among the modifiers were 17 loss-of-function suppressors of neurodegeneration, which can be considered potential targets for therapeutic intervention. Finally, we show that seven interacting proteins from among 11 tested were able to

Cross-cultural adaptation and reproducibility of the Brazilian-Portuguese version of the modified FRESNO Test to evaluate the competence in evidence based practice by physical therapists

Science.gov (United States)

Silva, Anderson M.; Costa, Lucíola C. M.; Comper, Maria L.; Padula, Rosimeire S.

2016-01-01

BACKGROUND: The Modified Fresno Test was developed to assess knowledge and skills of both physical therapy (PT) professionals and students to use evidence-based practice (EBP). OBJECTIVES: To translate the Modified Fresno Test into Brazilian-Portuguese and to evaluate the test's reproducibility. METHOD: The first step consisted of adapting the instrument into the Brazilian-Portuguese language. Then, a total of 57 participants, including PT students, PT professors and PT practitioners, completed the translated instrument. The responses from the participants were used to evaluate reproducibility of the translated instrument. Internal consistency was calculated using the Cronbach's alpha. Reliability was calculated using the intraclass correlation coefficient (ICC) for continuous variables, and the Kappa coefficient (K) for categorical variables. The agreement was assessed using the standard error of the measurement (SEM). RESULTS: The cross-cultural adaptation process was appropriate, providing an adequate Brazilian-Portuguese version of the instrument. The internal consistency was good (α=0.769). The reliability for inter- and intra-rater assessment were ICC=0.89 (95% CI 0.82 to 0.93); for evaluator 1 was ICC=0.85 (95% CI 0.57 to 0.93); and for evaluator 2 was ICC=0.98 (95% CI 0.97 to 0.99). The SEM was 13.04 points for inter-rater assessment, 12.57 points for rater 1 and 4.59 points for rater 2. CONCLUSION: The Brazilian-Portuguese language version of the Modified Fresno Test showed satisfactory results in terms of reproducibility. The Modified Fresno Test will allow physical therapy professionals and students to be evaluated on the use of understanding EBP. PMID:26786079

Cross-cultural adaptation and reproducibility of the Brazilian-Portuguese version of the modified FRESNO Test to evaluate the competence in evidence based practice by physical therapists

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Anderson M. Silva

2016-02-01

Full Text Available BACKGROUND: The Modified Fresno Test was developed to assess knowledge and skills of both physical therapy (PT professionals and students to use evidence-based practice (EBP. OBJECTIVES: To translate the Modified Fresno Test into Brazilian-Portuguese and to evaluate the test's reproducibility. METHOD: The first step consisted of adapting the instrument into the Brazilian-Portuguese language. Then, a total of 57 participants, including PT students, PT professors and PT practitioners, completed the translated instrument. The responses from the participants were used to evaluate reproducibility of the translated instrument. Internal consistency was calculated using the Cronbach's alpha. Reliability was calculated using the intraclass correlation coefficient (ICC for continuous variables, and the Kappa coefficient (K for categorical variables. The agreement was assessed using the standard error of the measurement (SEM. RESULTS: The cross-cultural adaptation process was appropriate, providing an adequate Brazilian-Portuguese version of the instrument. The internal consistency was good (α=0.769. The reliability for inter- and intra-rater assessment were ICC=0.89 (95% CI 0.82 to 0.93; for evaluator 1 was ICC=0.85 (95% CI 0.57 to 0.93; and for evaluator 2 was ICC=0.98 (95% CI 0.97 to 0.99. The SEM was 13.04 points for inter-rater assessment, 12.57 points for rater 1 and 4.59 points for rater 2. CONCLUSION: The Brazilian-Portuguese language version of the Modified Fresno Test showed satisfactory results in terms of reproducibility. The Modified Fresno Test will allow physical therapy professionals and students to be evaluated on the use of understanding EBP.

Reducing ultrafiltration membrane fouling during potable water reuse using pre-ozonation.

Science.gov (United States)

Wang, Hui; Park, Minkyu; Liang, Heng; Wu, Shimin; Lopez, Israel J; Ji, Weikang; Li, Guibai; Snyder, Shane A

2017-11-15

Wastewater reclamation has increasingly become popular to secure potable water supply. Low-pressure membrane processes such as microfiltration (MF) and ultrafiltration (UF) play imperative roles as a barrier of macromolecules for such purpose, but are often limited by membrane fouling. Effluent organic matter (EfOM), including biopolymers and particulates, in secondary wastewater effluents have been known to be major foulants in low-pressure membrane processes. Hence, the primary aim of this study was to investigate the effects of pre-ozonation as a pre-treatment for UF on the membrane fouling caused by EfOM in secondary wastewater effluents for hydrophilic regenerated cellulose (RC) and hydrophobic polyethersulfone (PES) UF membranes. It was found that greater fouling reduction was achieved by pre-ozonation for the hydrophilic RC membrane than the hydrophobic PES membrane at increasing ozone doses. In addition, the physicochemical property changes of EfOM, including biopolymer fractions, by pre-ozonation were systemically investigated. The classical pore blocking model and the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theories were employed to scrutinize the fouling alleviation mechanism by pre-ozonation. As a result, the overarching mechanisms of fouling reduction were attributed to the following key reasons: (1) Ozone degraded macromolecules such as biopolymers like proteins and polysaccharides into smaller fractions, thereby increasing free energy of cohesion of EfOM and rendering them more hydrophilic and stable; (2) pre-ozonation augmented the interfacial free energy of adhesion between foulants and the RC/PES membranes, leading to the increase of repulsions and/or the decrease of attractions; and (3) pre-ozonation prolonged the transition from pore blocking to cake filtration that was a dominant fouling mechanism, thereby reducing fouling. Copyright © 2017 Elsevier Ltd. All rights reserved.

Selective separation and concentration of antihypertensive peptides from rapeseed protein hydrolysate by electrodialysis with ultrafiltration membranes.

Science.gov (United States)

He, Rong; Girgih, Abraham T; Rozoy, Elodie; Bazinet, Laurent; Ju, Xing-Rong; Aluko, Rotimi E

2016-04-15

Rapeseed protein isolate was subjected to alcalase digestion to obtain a protein hydrolysate that was separated into peptide fractions using electrodialysis with ultrafiltration membrane (EDUF) technology. The EDUF process (6h duration) led to isolation of three peptide fractions: anionic (recovered in KCl-1 compartment), cationic (recovered in KCl-2 compartment), and those that remained in the feed compartment, which was labeled final rapeseed protein hydrolysate (FRPH). As expected the KCl-1 peptides were enriched in negatively-charged (43.57%) while KCl-2 contained high contents of positively-charged (28.35%) amino acids. All the samples inhibited angiotensin converting enzyme (ACE) and renin activities in dose-dependent manner with original rapeseed protein hydrolysate having the least ACE-inhibitory IC50 value of 0.0932±0.0037 mg/mL while FRPH and KCl-2 had least renin-inhibitory IC50 values of 0.47±0.05 and 0.55±0.06 mg/mL, respectively. Six hours after oral administration (100 mg/kg body weight) to spontaneously hypertensive rats, the FRPH produced the maximum systolic blood pressure reduction of -51 mmHg. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of different concentrations of nisin on starter culture of model Cheeses manufactured from ultrafiltrated milk

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Kh Mohammadi

2013-05-01

Full Text Available Nisin is a natural preservative produced by strains of Lactococcuslactis subsp. Lactis, has been approved for use in food by the Joint Food and Agricultural Organization/World Health Organization (FAO/WHO Committee on Food Additives and has been awarded generally recognized as safe (GRAS. It remains the only bacteriocin allowed in food as an addedpreservative. Nisin has a broad spectrum of antimicrobial activity againstgram-positive bacteria, thus one of the problems associated with nisin application is inhibition of starter culture and prevention of ripening, which is required for development of cheese characteristics during ripening. In the current study, the effects of different concentrations of nisin and temperature on growth and activity of lactic acid bacteria in model cheeses manufactured from ultrafiltrated milk was evaluated. Cheese samples were supplemented with nisin at concentrations of 0, 2, 4 and 6 µg/g and stored at 8 and 25 °C up to 60 days. Microbiological and physico-chemical properties of the cheese samples were analyzedat 0, 1, 8, 15, 30, 45 and 60 days. Results showed that addition of nisin at concentrations of 4 and 6 µg/g affects (p

Contribution of different effluent organic matter fractions to membrane fouling in ultrafiltration of treated domestic wastewater

KAUST Repository

Zheng, Xing; Croue, Jean-Philippe

2012-01-01

In the present work, effluent organic matter (EfOM) in treated domestic wastewater was separated into hydrophobic neutrals, colloids, hydrophobic acids, transphilic acids and neutrals and hydrophilic compounds. Their contribution to dissolved organic carbon (DOC) was identified. Further characterization was conducted with respect to molecular size and hydrophobicity. Each isolated fraction was dosed into salt solution to identify its fouling potential in ultrafiltration (UF) using a hydrophilized polyethersulfone membrane. The results show that each kind of EfOM leads to irreversible fouling. At similar delivered DOC load to the membrane, colloids present the highest fouling effect in terms of both reversible and irreversible fouling. The hydrophobic organics show much lower reversibility than the biopolymers present. However, as they are of much smaller size than the membrane pore opening, they cannot lead to such severe fouling as biopolymers do. In all of the isolated fractions, hydrophilics show the lowest fouling potential. For either colloids or hydrophobic substances, increasing their content in feedwater leads to worse fouling. The co-effect between biopolymers and other EfOM fractions has also been identified as one of the mechanisms contributing to UF fouling in filtering EfOM-containing waters. © IWA Publishing 2012.

Contribution of different effluent organic matter fractions to membrane fouling in ultrafiltration of treated domestic wastewater

KAUST Repository

Zheng, Xing

2012-12-01

In the present work, effluent organic matter (EfOM) in treated domestic wastewater was separated into hydrophobic neutrals, colloids, hydrophobic acids, transphilic acids and neutrals and hydrophilic compounds. Their contribution to dissolved organic carbon (DOC) was identified. Further characterization was conducted with respect to molecular size and hydrophobicity. Each isolated fraction was dosed into salt solution to identify its fouling potential in ultrafiltration (UF) using a hydrophilized polyethersulfone membrane. The results show that each kind of EfOM leads to irreversible fouling. At similar delivered DOC load to the membrane, colloids present the highest fouling effect in terms of both reversible and irreversible fouling. The hydrophobic organics show much lower reversibility than the biopolymers present. However, as they are of much smaller size than the membrane pore opening, they cannot lead to such severe fouling as biopolymers do. In all of the isolated fractions, hydrophilics show the lowest fouling potential. For either colloids or hydrophobic substances, increasing their content in feedwater leads to worse fouling. The co-effect between biopolymers and other EfOM fractions has also been identified as one of the mechanisms contributing to UF fouling in filtering EfOM-containing waters. © IWA Publishing 2012.

Modified Gravity and its test on galaxy clusters

Science.gov (United States)

Nieuwenhuizen, Theodorus M.; Morandi, Andrea; Limousin, Marceau

2018-05-01

The MOdified Gravity (MOG) theory of J. Moffat assumes a massive vector particle which causes a repulsive contribution to the tensor gravitation. For the galaxy cluster A1689 new data for the X-ray gas and the strong lensing properties are presented. Fits to MOG are possible by adjusting the galaxy density profile. However, this appears to work as an effective dark matter component, posing a serious problem for MOG. New gas and strong lensing data for the cluster A1835 support these conclusions and point at a tendency of the gas alone to overestimate the lensing effects in MOG theory.

Dynamic behaviour of river colloidal and dissolved organic matter through cross-flow ultrafiltration system.

Science.gov (United States)

Wilding, Andrew; Liu, Ruixia; Zhou, John L

2005-07-01

Through cross-flow filtration (CFF) with a 1-kDa regenerated cellulose Pellicon 2 module, the ultrafiltration characteristics of river organic matter from Longford Stream, UK, were investigated. The concentration of organic carbon (OC) in the retentate in the Longford Stream samples increased substantially with the concentration factor (cf), reaching approximately 40 mg/L at cf 15. The results of dissolved organic carbon (DOC) and colloidal organic carbon (COC) analysis, tracking the isolation of colloids from river waters, show that 2 mg/L of COC was present in those samples and good OC mass balance (77-101%) was achieved. Fluorescence measurements were carried out for the investigation of retentate and permeate behaviour of coloured dissolved organic materials (CDOM). The concentrations of CDOM in both the retentate and permeate increased with increasing cf, although CDOM were significantly more concentrated in the retentate. The permeation model expressing the correlation between log[CDOM] in the permeate and logcf was able to describe the permeation behaviour of CDOM in the river water with regression coefficients (r(2)) of 0.94 and 0.98. Dry weight analysis indicated that the levels of organic colloidal particles were from 49 to 71%, and between 29 and 51% of colloidal particles present were inorganic. COC as a percentage of DOC was found to be 10-16% for Longford Stream samples.

Separation Properties of Wastewater Containing O/W Emulsion Using Ceramic Microfiltration/Ultrafiltration (MF/UF Membranes

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Kanji Matsumoto

2013-06-01

Full Text Available Washing systems using water soluble detergent are used in electrical and mechanical industries and the wastewater containing O/W emulsion are discharged from these systems. Membrane filtration has large potential for the efficient separation of O/W emulsion for reuses of treated water and detergent. The separation properties of O/W emulsions by cross-flow microfiltration and ultrafiltration were studied with ceramic MF and UF membranes. The effects of pore size; applied pressure; cross-flow velocity; and detergent concentration on rejection of O/W emulsion and flux were systematically studied. At the condition achieving complete separation of O/W emulsion the pressure-independent flux was observed and this flux behavior was explained by gel-polarization model. The O/W emulsion tended to permeate through the membrane at the conditions of larger pore size; higher emulsion concentration; and higher pressure. The O/W emulsion could permeate the membrane pore structure by destruction or deformation. These results imply the stability of O/W emulsion in the gel-layer formed on membrane surface play an important role in the separation properties. The O/W emulsion was concentrated by batch cross-flow concentration filtration and the flux decline during the concentration filtration was explained by the gel- polarization model.

Separation Properties of Wastewater Containing O/W Emulsion Using Ceramic Microfiltration/Ultrafiltration (MF/UF) Membranes

Science.gov (United States)

Nakamura, Kazuho; Matsumoto, Kanji

2013-01-01

Washing systems using water soluble detergent are used in electrical and mechanical industries and the wastewater containing O/W emulsion are discharged from these systems. Membrane filtration has large potential for the efficient separation of O/W emulsion for reuses of treated water and detergent. The separation properties of O/W emulsions by cross-flow microfiltration and ultrafiltration were studied with ceramic MF and UF membranes. The effects of pore size; applied pressure; cross-flow velocity; and detergent concentration on rejection of O/W emulsion and flux were systematically studied. At the condition achieving complete separation of O/W emulsion the pressure-independent flux was observed and this flux behavior was explained by gel-polarization model. The O/W emulsion tended to permeate through the membrane at the conditions of larger pore size; higher emulsion concentration; and higher pressure. The O/W emulsion could permeate the membrane pore structure by destruction or deformation. These results imply the stability of O/W emulsion in the gel-layer formed on membrane surface play an important role in the separation properties. The O/W emulsion was concentrated by batch cross-flow concentration filtration and the flux decline during the concentration filtration was explained by the gel- polarization model. PMID:24958621

Nanofiltration and Tight Ultrafiltration Membranes for the Recovery of Polyphenols from Agro-Food By-Products

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Alfredo Cassano

2018-01-01

Full Text Available Pressure-driven membrane-based technologies represent a valid approach to reduce the environmental pollution of several agro-food by-products. Recently, in relation to the major interest for natural compounds with biological activities, their use has been also addressed to the recovery, separation and fractionation of phenolic compounds from such by-products. In particular, tight ultrafiltration (UF and nanolfiltration (NF membranes have been recognized for their capability to recover phenolic compounds from several types of agro-food by-products. The separation capability of these membranes, as well as their productivity, depends on multiple factors such as membrane material, molecular weight cut-off (MWCO and operating conditions (e.g., pressure, temperature, feed flow rate, volume reduction factor, etc.. This paper aims at providing a critical overview of the influence of these parameters on the recovery of phenolic compounds from agro-food by-products by using tight UF and NF membranes. The literature data are analyzed and discussed in relation to separation processes, molecule properties, membrane characteristics and other phenomena occurring in the process. Current extraction methodologies of phenolic compounds from raw materials are also introduced in order to drive the implementation of integrated systems for the production of actractive phenolic formulations of potential interest as food antioxidants.

Nanofiltration and Tight Ultrafiltration Membranes for the Recovery of Polyphenols from Agro-Food By-Products.

Science.gov (United States)

Cassano, Alfredo; Conidi, Carmela; Ruby-Figueroa, René; Castro-Muñoz, Roberto

2018-01-24

Pressure-driven membrane-based technologies represent a valid approach to reduce the environmental pollution of several agro-food by-products. Recently, in relation to the major interest for natural compounds with biological activities, their use has been also addressed to the recovery, separation and fractionation of phenolic compounds from such by-products. In particular, tight ultrafiltration (UF) and nanolfiltration (NF) membranes have been recognized for their capability to recover phenolic compounds from several types of agro-food by-products. The separation capability of these membranes, as well as their productivity, depends on multiple factors such as membrane material, molecular weight cut-off (MWCO) and operating conditions (e.g., pressure, temperature, feed flow rate, volume reduction factor, etc.). This paper aims at providing a critical overview of the influence of these parameters on the recovery of phenolic compounds from agro-food by-products by using tight UF and NF membranes. The literature data are analyzed and discussed in relation to separation processes, molecule properties, membrane characteristics and other phenomena occurring in the process. Current extraction methodologies of phenolic compounds from raw materials are also introduced in order to drive the implementation of integrated systems for the production of actractive phenolic formulations of potential interest as food antioxidants.

Human procollagen type I surface-modified PHB-based non-woven textile scaffolds for cell growth: preparation and short-term biological tests

International Nuclear Information System (INIS)

Kawalec, Michał; Sobota, Michał; Kurcok, Piotr; Sitkowska, Anna; Sieroń, Aleksander L; Komar, Patrycja

2014-01-01

3D fine porous structures obtained by electrospinning a poly[(R,S)-3-hydroxybutyrate] (aPHB)/ poly[(R)-3-hydroxybutyrate] (PHB) (85/15 w/w) blend were successfully modified with human procollagen type I by simple immersion of the polyester scaffold in an aqueous solution of the protein. Effective modification of the scaffold with human procollagen I was confirmed by an immunodetection test, which revealed the presence of the procollagen type I as an outer layer even on inner structures of the porous matrixes. Biological tests of 3D fabrics made of the PHB blend provide support for the adhesion and proliferation of human fibroblasts, while their modification with procollagen type I increased the biocompatibility of the final scaffolds significantly, as shown by the notable increase in the number of attached cells during the early hours of their incubation. Based on these findings, human procollagen type I surface-modified aPHB/PHB scaffolds should be considered a promising material in regenerative medicine. (paper)

Effect of nanosilica particles on polypropylene polymer modified asphalt mixture performance

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Nura Bala

2018-06-01

Full Text Available The current study was conducted to investigate the effect of nanosilica particles on the performance characteristics of polymer modified asphalt binders. In this study, control 80/100 binder were modified with polypropylene polymer and nanosilica particles at concentration of 0%–4%. Both nanosilica particles and polypropylene polymer were added by weight of total bitumen content. The asphalt performance tests flexural four point beam fatigue test, indirect tensile strength, indirect tensile stiffness modulus and draindown tests are conducted to evaluate the effect of nanosilica particles. The results of the study shows that nanosilica particles improves the fatigue properties of polypropylene polymer modified binder. This indicates that nanosilica particles have significant effect on improving the performance properties of polymer modified binders. Also, the result reveals that thermoplastic polymer polypropylene with nanosilica particles when used as bitumen modifiers improve the performance and durability of asphalt mixtures. Keywords: Polypropylene, Fatigue cracking, Stiffness modulus, Modified asphalt, Draindown

How Do Polyethylene Glycol and Poly(sulfobetaine) Hydrogel Layers on Ultrafiltration Membranes Minimize Fouling and Stay Stable in Cleaning Chemicals?

KAUST Repository

Le, Ngoc Lieu

2017-05-18

We compare the efficiency of grafting polyethylene glycol (PEG) and poly(sulfobetaine) hydrogel layer on poly(ether imide) (PEI) hollow-fiber ultrafiltration membrane surfaces in terms of filtration performance, fouling minimization and stability in cleaning solutions. Two previously established different methods toward the two different chemistries (and both had already proven to be suited to reduce fouling significantly) are applied to the same PEI membranes. The hydrophilicity of PEI membranes is improved by the modification, as indicated by the change of contact angle value from 89° to 68° for both methods, due to the hydration layer formed in the hydrogel layers. Their pure water flux declines because of the additional permeation barrier from the hydrogel layers. However, these barriers increase protein rejection. In the exposure at a static condition, grafting PEG or poly(sulfobetaine) reduces protein adsorption to 23% or 11%, respectively. In the dynamic filtration, the hydrogel layers minimizes the flux reduction and increases the reversibility of fouling. Compared to the pristine PEI membrane that can recover its flux to 42% after hydraulic cleaning, the PEG and poly(sulfobetaine) grafted membranes can recover their flux up to 63% and 94%, respectively. Stability tests show that the poly(sulfobetaine) hydrogel layer is stable in acid, base and chlorine solutions, whereas the PEG hydrogel layer suffers alkaline hydrolysis in base and oxidation in chlorine conditions. With its chemical stability and pronounced capability of minimizing fouling, especially irreversible fouling, protective poly(sulfobetaine) hydrogel layers have great potential for various membrane-based applications.

Trends analysis of rainfall and rainfall extremes in Sarawak, Malaysia using modified Mann-Kendall test

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Sa'adi, Zulfaqar; Shahid, Shamsuddin; Ismail, Tarmizi; Chung, Eun-Sung; Wang, Xiao-Jun

2017-11-01

This study assesses the spatial pattern of changes in rainfall extremes of Sarawak in recent years (1980-2014). The Mann-Kendall (MK) test along with modified Mann-Kendall (m-MK) test, which can discriminate multi-scale variability of unidirectional trend, was used to analyze the changes at 31 stations. Taking account of the scaling effect through eliminating the effect of autocorrelation, m-MK was employed to discriminate multi-scale variability of the unidirectional trends of the annual rainfall in Sarawak. It can confirm the significance of the MK test. The annual rainfall trend from MK test showed significant changes at 95% confidence level at five stations. The seasonal trends from MK test indicate an increasing rate of rainfall during the Northeast monsoon and a decreasing trend during the Southwest monsoon in some region of Sarawak. However, the m-MK test detected an increasing trend in annual rainfall only at one station and no significant trend in seasonal rainfall at any stations. The significant increasing trends of the 1-h maximum rainfall from the MK test are detected mainly at the stations located in the urban area giving concern to the occurrence of the flash flood. On the other hand, the m-MK test detected no significant trend in 1- and 3-h maximum rainfalls at any location. On the contrary, it detected significant trends in 6- and 72-h maximum rainfalls at a station located in the Lower Rajang basin area which is an extensive low-lying agricultural area and prone to stagnant flood. These results indicate that the trends in rainfall and rainfall extremes reported in Malaysia and surrounding region should be verified with m-MK test as most of the trends may result from scaling effect.

Influence Of The Gripping Fixture On The Modified Compact Tension Test Results: Evaluation Of The Experiments On Cylindrical Concrete Specimens

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Holušová Táňa

2015-12-01

Full Text Available The modified compact tension test (MCT might become in the future a stable test configuration for the evaluation of fracture-mechanics parameters or also for description of fatigue behavior of composites materials such as concrete. Core drilling is used for sampling of existing structures. These samples have cylindrical shape with the selected thickness to avoid the stress concentration. This contribution focuses on the evaluation of the fracture behavior during static and quasi static tests. Static tests are performed on standard specimen with diameter 150 mm and length 300 mm. The quasi-static tests are performed using two different gripping fixtures. The results for quasi-static tests are represented as L-COD diagrams (i.e. load vs. crack opening displacement measured on the loading axis. The comparison of results and discussion of advantages and disadvantages are introduced.

Cross-Cultural Adaptation, Validation, and Reliability Testing of the Modified Oswestry Disability Questionnaire in Persian Population with Low Back Pain.

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Baradaran, Aslan; Ebrahimzadeh, Mohammad H; Birjandinejad, Ali; Kachooei, Amir Reza

2016-04-01

Prospective study. We aimed to validate the Persian version of the modified Oswestry disability questionnaire (MODQ) in patients with low back pain. Modified Oswestry low back pain disability questionnaire is a well-known condition-specific outcome measure that helps quantify disability in patients with lumbar syndromes. To test the validity in a pilot study, the Persian MODQ was administered to 25 individuals with low back pain. We then enrolled 200 consecutive patients with low back pain to fill the Persian MODQ as well as the short form 36 (SF-36) questionnaire. Convergent validity of the MODQ was tested using the Spearman's correlation coefficient between the MODQ and SF-36 subscales. Intraclass correlation coefficient (ICC) and Cronbach's α coefficient were measured to test the reliability between test and retest and internal consistency of all items, respectively. ICC for individual items ranged from 0.43 to 0.80 showing good reliability and reproducibility of each individual item. Cronbach's α coefficient was 0.69 showing good internal consistency across all 10 items of the Persian MODQ. Total MODQ score showed moderate to strong correlation with the eight subscales and the two domains of the SF-36. The highest correlation was between the MODQ and the physical functioning subscale of the SF-36 (r=-0.54, pPersian version of the MODQ is a valid and reliable tool for the assessment of the disability following low back pain.

Ionic-liquid-based ultrasound-assisted extraction of isoflavones from Belamcanda chinensis and subsequent screening and isolation of potential α-glucosidase inhibitors by ultrafiltration and semipreparative high-performance liquid chromatography.

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Li, Senlin; Li, Sainan; Huang, Yu; Liu, Chunming; Chen, Lina; Zhang, Yuchi

2017-06-01

The separation of a compound of interest from its structurally similar homologues to produce high-purity natural products is a challenging problem. This work proposes a novel method for the separation of iristectorigenin A from its structurally similar homologues by ionic-liquid-based ultrasound-assisted extraction and the subsequent screening and isolation of potential α-glucosidase inhibitors via ultrafiltration and semipreparative high-performance liquid chromatography. Ionic-liquid-based ultrasound-assisted extraction was successfully applied to the extraction of tectorigenin, iristectorigenin A, irigenin, and irisflorentin from Belamcanda chinensis. The optimum conditions for the efficient extraction of isoflavones were determined as 1.0 M 1-ethyl-3-methylimidazolium tetrafluoroborate with extraction time of 30 min and a solvent to solid ratio of 30 mL/g. Ultrafiltration with liquid chromatography and mass spectrometry was applied to screen and identify α-glucosidase inhibitors from B. chinensis, followed by the application of semipreparative high-performance liquid chromatography to separate and isolate the active constituents. Four major compounds including tectorigenin, iristectorigenin A, irigenin, and irisflorentin were screened and identified as α-glucosidase inhibitors, and then the four active compounds abovementioned were subsequently isolated by semipreparative high-performance liquid chromatography (99.89, 88.97, 99.79, and 99.97% purity, respectively). The results demonstrate that ionic liquid extraction can be successfully applied to the extraction of isoflavones from B. chinensis. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A Modified Murine Embryonic Stem Cell Test for Evaluating the Teratogenic Effects of Drugs on Early Embryogenesis.

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Ruoxing Yu

Full Text Available Mammalian fetal development is easily disrupted by exogenous agents, making it essential to test new drug candidates for embryotoxicity and teratogenicity. To standardize the testing of drugs that might be used to treat pregnant women, the U.S. Food and Drug Administration (FDA formulated special grade categories, labeled A, B, C, D and X, that define the level of risk associated with the use of a specific drug during pregnancy. Drugs in categories (Cat. D and X are those with embryotoxic and/or teratogenic effects on humans and animals. However, which stages of pregnancy are affected by these agents and their molecular mechanisms are unknown. We describe here an embryonic stem cell test (EST that classifies FDA pregnancy Cat.D and Cat.X drugs into 4 classes based on their differing effects on primitive streak formation. We show that ~84% of Cat.D and Cat.X drugs target this period of embryogenesis. Our results demonstrate that our modified EST can identify how a drug affects early embryogenesis, when it acts, and its molecular mechanism. Our test may thus be a useful addition to the drug safety testing armamentarium.

Intermittent operation of ultra-low pressure ultrafiltration for decentralized drinking water treatment.

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Peter-Varbanets, Maryna; Gujer, Willi; Pronk, Wouter

2012-06-15

River water was treated by ultrafiltration at a relatively low transmembrane pressure (40 mbar). As observed before, flux stabilization occurred after several days of operation although no back-flushing or cross flow was applied. Interruptions in flux were applied by temporary offset of the transmembrane pressure. After restoration of the transmembrane pressure, the initial flux was higher than the stable flux level, and the flux recovery depended on the standstill time. Furthermore, if a short cross flow was applied after standstill, the flux was restored to an even higher level. In all cases, the flux decreased again during operation to reach finally the same stable level as before standstill. In order to evaluate the influence of intermittent operation as practiced for water treatment on a household level, daily interruptions of flux were applied. An optimum of total daily water production rate was obtained at 21 h of operation and 3 h of standstill per day. A model was developed which can describe the impact of intermittent operation on the flux depending on the duration of the standstill and operating periods. This enables the prediction of production capacity of the system operated intermittently. The flux increase during standstill could be explained by a relaxation and expansion of the biofouling layer, while the higher flux after forward-flushing was caused by this layer being partially sloughed off. Household water treatment with the process presented here will generally be operated on a discontinuous basis. The results show that such operation schemes do not compromise the permeability of the system, but actually lead to higher fluxes after standstill. Copyright © 2012 Elsevier Ltd. All rights reserved.

Nonlinearities in modified gravity cosmology: Signatures of modified gravity in the nonlinear matter power spectrum

International Nuclear Information System (INIS)

Cui Weiguang; Zhang Pengjie; Yang Xiaohu

2010-01-01

A large fraction of cosmological information on dark energy and gravity is encoded in the nonlinear regime. Precision cosmology thus requires precision modeling of nonlinearities in general dark energy and modified gravity models. We modify the Gadget-2 code and run a series of N-body simulations on modified gravity cosmology to study the nonlinearities. The modified gravity model that we investigate in the present paper is characterized by a single parameter ζ, which determines the enhancement of particle acceleration with respect to general relativity (GR), given the identical mass distribution (ζ=1 in GR). The first nonlinear statistics we investigate is the nonlinear matter power spectrum at k < or approx. 3h/Mpc, which is the relevant range for robust weak lensing power spectrum modeling at l < or approx. 2000. In this study, we focus on the relative difference in the nonlinear power spectra at corresponding redshifts where different gravity models have the same linear power spectra. This particular statistics highlights the imprint of modified gravity in the nonlinear regime and the importance of including the nonlinear regime in testing GR. By design, it is less susceptible to the sample variance and numerical artifacts. We adopt a mass assignment method based on wavelet to improve the power spectrum measurement. We run a series of tests to determine the suitable simulation specifications (particle number, box size, and initial redshift). We find that, the nonlinear power spectra can differ by ∼30% for 10% deviation from GR (|ζ-1|=0.1) where the rms density fluctuations reach 10. This large difference, on one hand, shows the richness of information on gravity in the corresponding scales, and on the other hand, invalidates simple extrapolations of some existing fitting formulae to modified gravity cosmology.

Preparation and Characterization of Thin-Film Composite Membrane with Nanowire-Modified Support for Forward Osmosis Process

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Low, Ze-Xian; Liu, Qi; Shamsaei, Ezzatollah; Zhang, Xiwang; Wang, Huanting

2015-01-01

Internal concentration polarization (ICP) in forward osmosis (FO) process is a characteristic problem for asymmetric thin-film composite (TFC) FO membrane which leads to lower water flux. To mitigate the ICP effect, modification of the substrates’ properties has been one of the most effective methods. A new polyethersulfone-based ultrafiltration membrane with increased surface porosity and high water flux was recently produced by incorporating Zn2GeO4 nanowires. The composite membrane was used as a substrate for the fabrication of TFC FO membrane, by coating a thin layer of polyamide on top of the substrate. The substrate and the nanowires were characterized by a range of techniques such as SEM, XRD, and contact angle goniometry. The water permeability and molecular weight cut-offs (MWCO) of the substrate; and the FO performance of the TFC membrane were also determined. The Zn2GeO4-modified membrane showed ~45% increase in water permeability and NaCl salt rejection of 80% under RO mode. In FO mode, the ratio of water flux to reverse solute flux was also improved. However, lower FO flux was obtained which could be due to ICP. The result shows that Zn2GO4 nanowire may be used as a modifier to the substrate to improve the quality of the polyamide layer on the substrate to improve the flux and selectivity, but not as effective in reducing ICP. This work demonstrates that the incorporation of nanomaterials to the membrane substrate may be an alternative approach to improve the formation of polyamide skin layer to achieve better FO performance. PMID:25803239

Preparation and Characterization of Thin-Film Composite Membrane with Nanowire-Modified Support for Forward Osmosis Process

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Ze-Xian Low

2015-03-01

Full Text Available Internal concentration polarization (ICP in forward osmosis (FO process is a characteristic problem for asymmetric thin-film composite (TFC FO membrane which leads to lower water flux. To mitigate the ICP effect, modification of the substrates’ properties has been one of the most effective methods. A new polyethersulfone-based ultrafiltration membrane with increased surface porosity and high water flux was recently produced by incorporating Zn2GeO4 nanowires. The composite membrane was used as a substrate for the fabrication of TFC FO membrane, by coating a thin layer of polyamide on top of the substrate. The substrate and the nanowires were characterized by a range of techniques such as SEM, XRD, and contact angle goniometry. The water permeability and molecular weight cut-offs (MWCO of the substrate; and the FO performance of the TFC membrane were also determined. The Zn2GeO4-modified membrane showed ~45% increase in water permeability and NaCl salt rejection of 80% under RO mode. In FO mode, the ratio of water flux to reverse solute flux was also improved. However, lower FO flux was obtained which could be due to ICP. The result shows that Zn2GO4 nanowire may be used as a modifier to the substrate to improve the quality of the polyamide layer on the substrate to improve the flux and selectivity, but not as effective in reducing ICP. This work demonstrates that the incorporation of nanomaterials to the membrane substrate may be an alternative approach to improve the formation of polyamide skin layer to achieve better FO performance.

Comparison of Sleep Latency and Number of SOREMPs in the Home and Hospital With a Modified Multiple Sleep Latency Test: A Randomized Crossover Study.

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Beiske, Kornelia K; Sand, Trond; Rugland, Eyvind; Stavem, Knut

2017-05-01

Comparison of mean sleep latencies and number of sleep-onset rapid eye movement periods (SOREMPs) between modified multiple sleep latency test (MSLT) performed in the unattended home and in-hospital laboratory setting. A randomized crossover single-blinded design. Thirty-four subjects referred to MSLT for suspected hypersomnia or narcolepsy were included. Participants were randomized to perform modified MSLT in the unattended home or in the hospital first. Scores in the two settings were compared using Wilcoxon signed-rank test or exact McNemar test. Agreement between home and hospital categorized mean sleep latency and number of SOREMPs was assessed using simple kappa (κ) and proportion agreement. Agreement between home and hospital mean sleep latency was assessed using a Bland-Altman plot and an intraclass correlation coefficient. There was no difference between home and hospital assessment of mean sleep latency (P = 0.86). Two or more SOREMPs were found more frequently on modified MSLTs performed at home compared with those at the hospital (7 and 2, respectively; P = 0.025). Agreement was moderate for categorized sleep latency (κ = 0.53) and fair for categorized SOREMPs (κ = 0.39) in the 2 settings. Analysis of mean sleep latency using intraclass correlation coefficient showed a very good agreement between the two settings. Group mean sleep latency for home modified MSLTs seems to be reliable compared with that for the attended sleep-laboratory setting. Higher rate of SOREMP in the unattended home suggests that napping in a familiar environment facilitates the transition into REM sleep. Further studies are needed to assess the normal limit, sensitivity, and specificity for SOREMP at home before the clinical utility of home-based napping can be determined.

Testing a Modified PCA-Based Sharpening Approach for Image Fusion

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Jan Jelének

2016-09-01

Full Text Available Image data sharpening is a challenging field of remote sensing science, which has become more relevant as high spatial-resolution satellites and superspectral sensors have emerged. Although the spectral property is crucial for mineral mapping, spatial resolution is also important as it allows targeted minerals/rocks to be identified/interpreted in a spatial context. Therefore, improving the spatial context, while keeping the spectral property provided by the superspectral sensor, would bring great benefits for geological/mineralogical mapping especially in arid environments. In this paper, a new concept was tested using superspectral data (ASTER and high spatial-resolution panchromatic data (WorldView-2 for image fusion. A modified Principal Component Analysis (PCA-based sharpening method, which implements a histogram matching workflow that takes into account the real distribution of values, was employed to test whether the substitution of Principal Components (PC1–PC4 can bring a fused image which is spectrally more accurate. The new approach was compared to those most widely used—PCA sharpening and Gram–Schmidt sharpening (GS, both available in ENVI software (Version 5.2 and lower as well as to the standard approach—sharpening Landsat 8 multispectral bands (MUL using its own panchromatic (PAN band. The visual assessment and the spectral quality indicators proved that the spectral performance of the proposed sharpening approach employing PC1 and PC2 improve the performance of the PCA algorithm, moreover, comparable or better results are achieved compared to the GS method. It was shown that, when using the PC1, the visible-near infrared (VNIR part of the spectrum was preserved better, however, if the PC2 was used, the short-wave infrared (SWIR part was preserved better. Furthermore, this approach improved the output spectral quality when fusing image data from different sensors (e.g., ASTER and WorldView-2 while keeping the proper albedo

Modified basin-type solar still

International Nuclear Information System (INIS)

El-Mously, M.K.; El-Ashry, M.Y.; El-Iraqi, M.H.

1981-07-01

A modified basin-type solar still (BTSS) has been developed. The new idea introduced is to re-use the latent heat due to condensation for increasing the temperature of saline water flowing into the device. A new term had been introduced in the balance of equation of conventional BTSS leading to the increase of the efficiency. According to the suggested model, a modified BTSS had been constructed and tested. It is found that the increase in the efficiency is about 14%. (author)

UV/H2O2 process performance improvement by ultrafiltration and physicochemical clarification systems for industrial effluent pretreatment

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Ivanildo Hespanhol

2012-12-01

Full Text Available The present study evaluated the removal of TOC from an effluent with high organic load resulted from the treatment of oil-water emulsion by thermal process. Hollow Fiber Ultrafiltration membrane (HF-UF and physicochemical clarification process were used as pretreatment options to assess the influence of feed effluent quality on the UV/H2O2 oxidation process. Results for TOC removals showed HF-UF and physicochemical clarification processes can significantly improve the efficiency of UV/H2O2 oxidation process, when compared with the direct effluent oxidation. Reaction time for obtaining a TOC removal higher than 90% was reduced to approximately half of the time needed when no pretreatment was applied. Considering both pretreatment processes it was not possible to notice any significant difference on the UV/H2O2 oxidation process performance. However, the complexity of physicochemical process due to the use of three different chemicals and sludge production made the HF-UF process the best pretreatment alternative, without increasing the Total Dissolved Solids of the effluent, a very important issue when water reuse is considered.

Preparation of steroid radioligands for ultrafiltration assays by a solid-phase transport globulin method using concanavalin A-Sepharose

International Nuclear Information System (INIS)

Hiramatsu, R.; Nisula, B.C.

1985-01-01

Concanavalin A-Sepharose (Con A-Sepharose) was applied to separate non-protein-bound and albumin-bound radioactive impurities from steroid radioligands. Con A-Sepharose gel, plasma, and steroid radioligand were mixed, incubated, and then washed with buffer. This method was compared with an affinity diafiltration method which separates non-protein-bound radioactive impurities with a filter membrane. 3 H-Water and 3 H-estrone sulfate, chosen to serve as molecules representative of non-protein-bound and albumin-bound impurities, were removed quite effectively by the Con A-Sepharose method, while 85% of 3 H-estrone sulfate could not be removed by the diafiltration method. Plasma unbound cortisol (F) and testosterone (T) values determined by ultrafiltration using 3 H-F and 3 H-T prepared by the Con A-Sepharose method were significantly lower than those determined using the radioligands unprocessed or prepared by the diafiltration method. The whole procedure of the Con A-Sepharose method takes only 3-4 hours. This method is a simple, rapid, and effective technique for preparation of steroid radioligands for plasma protein binding studies

Micellar Enhanced Ultrafiltration for the Removal of Polycyclic Aromatic Hydrocarbons (PAHs Mixtures in Underground Contaminated Water in Oman

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Mohamed Aoudia

2011-12-01

Full Text Available In an attempt to analyze polycyclic aromatic hydrocarbons (PAHs in diesel contaminated underground water in Oman (Rustaq, Gas chromatography-Mass spectrometry was first used to determine the different concentrations in a standard mixture containing 16 PAHs. Retention time and calibration curves were obtained for all aromatic compounds and were used to identify a given analyte as well as its concentration in the contaminated underground water. Micellar enhanced ultrafiltration (MEUF was then used to treat standard aqueous solution of PAHs at low concentration (~ 1 ppb using an edible nonionic surfactant (Tween 80. The totality of the mixture components was completely rejected. Within the experimental detection limit (± 0.01 ppb, the residual PAH concentrations were less than 0.01 ppb in accord with the allowed concentrations in drinking water. Likewise, excellent rejections of PAHs in MEUF treatment of diesel contaminated underground water at an Omani site (Rustaq were observed. The concentration of PAHs was reduced to less than 0.01 ppb, the accepted limit for the most toxic member of the PAH group (benzo(apyrene.