Relevant bibliographies by topics / Ultrafiltration

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Ultrafiltration'

Author: Grafiati
Published: 4 June 2021
Last updated: 7 September 2024

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Journal articles on the topic "Ultrafiltration"

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Tay, Kirsty Luo-Yng, Abdel Rahman Osman, Esyn Ee Xin Yeoh, Jasmine Luangboriboon, Jie Fei Lau, Joanne Jia An Chan, Majed Yousif, et al. "Ultrafiltration versus Diuretics on Prognostic Cardiac and Renal Biomarkers in Acute Decompensated Heart Failure: A Systematic Review and Meta-Analysis." Journal of Clinical Medicine 12, no. 8 (April 9, 2023): 2793. http://dx.doi.org/10.3390/jcm12082793.

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Existing systematic reviews have insufficiently delineated the differing cardiac and renal profile of ultrafiltration compared to diuretics as a method of decongestion in acute decompensated heart failure. This meta-analysis will investigate the impact of ultrafiltration compared to diuretics on prognostic cardiac and renal biomarkers. We searched PubMed Central, Ovid MEDLINE®, Ovid Embase, all EBM reviews, and Web of Science Core Collection for randomised controlled trials published before 21 July 2022. Our main outcome measures were cardiac (brain natriuretic peptide and N-terminal pro-brain natriuretic peptide) and renal biomarkers (serum creatinine, serum sodium, and blood urea nitrogen). A total of 10 randomised trials were included in our analysis after screening. An inverse-variance random effects meta-analysis of the pooled results demonstrated no significant difference between ultrafiltration and diuretics for brain natriuretic peptide, N-terminal pro-brain natriuretic peptide, creatinine, sodium and long-term blood urea nitrogen. However, ultrafiltration produced statistically greater increases in blood urea nitrogen in the short-term (mean difference, 3.88; 95% confidence interval 0.59–7.17 mg/dL). Overall, ultrafiltration produces a similar impact on prognostic cardiac and renal biomarkers when compared to diuretic therapy. We highlight ultrafiltration’s significant impact on short-term BUN and recommend further research to investigate more optimal protocols of ultrafiltration administration.
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Petterson, Craig M., Alfred H. Stammers, Ryan J. Kohtz, Scott A. Kmiecik, Jeffrey D. Nichols, Nancy J. Mills, and Jun-Li Liu. "The Effects of Ultrafiltration on e-Aminocaproic Acid: An In Vitro Analysis." Journal of ExtraCorporeal Technology 34, no. 3 (September 2002): 197–202. http://dx.doi.org/10.1051/ject/2002343197.

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Blood conservation strategies have become a standard of practice in cardiac surgery, with the use of antifibrinolytic agents and ultrafiltration two popular techniques. The purpose of this study was to evaluate the effects of continuous ultrafiltration on e-aminocaproic acid (EACA) utilizing functional coagulation analysis. A fibrinolytic assay was developed to detect EACA using the thromboelastograph (TEG) and urokinase (0.138 units 0.360 mL−1). Fresh bovine blood (23 ± 1% hematocrit) was pumped (100 mL min−1) through an ultrafiltrator (HPH 400) at 37°C with a transmembrane pressure of 280 mmHg. EACA (0.065 mg mL−1) was circulated for 10 minutes before initiating ultrafiltration. Samples (pre- and postultrafiltrator) were obtained at baseline, 5, and 10 min of ultrafiltration and analyzed via the fibrinolytic assay for EACA determination. TEG profiles significantly decreased from concentrations of 0.065 mg to 0.0325 mg of EACA mL−1 blood (maximum amplitude MA, 75.4 ± 4.0 versus 63.3 ± 2.9, p < .05, TEG index 5.4 ± 0.7 versus 4.0 ± 0.3, p < .05). Fibrinolysis at 30 min increased as EACA concentrations declined (0.065 mg, 0% versus 0.032 mg, 16.4 ± 2.8%, p < .05). During ultrafiltration the MA increased significantly from baseline to 10 min postultrafiltrator (68.2 ± 3.0 versus 75.8 ± 10.0, p < .05) and from 5 min pre- to 10 min postultrafiltrator (69.7 ± 4.2 versus 75.8 ± 10.0, p < .05). The TEG index showed no significant change, and no fibrinolysis was detected at 30 min from any datapoint during ultrafiltration. In conclusion, this study demonstrates that the antifibrinolytic properties of EACA are maintained during ultrafiltration with a 25% reduction in total circulating volume.
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Han, You Qi, De Ming Zhu, Zhou Kong Su, and Wen Xiang Ding. "Ultrafiltration in Pediatric Cardiac Surgical Procedures." Journal of ExtraCorporeal Technology 23, no. 3 (September 1991): 63–65. http://dx.doi.org/10.1051/ject/199123363.

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Ultrafiltration is an extracorporeal technique that employs the principle of convective solution transport across a semipermeable membrane and by which plasma water is removed from the dilute blood during cardiopulmonary bypass. Ultrafiltration has been used in 40 pediatric cases who underwent corrective surgery for congenital heart disease (TOF 12, VSD 23, ASD 4 and PAVC 1) intraoperatively. The patients' ages ranged from 10months to 9 years (4.9±2.6yrs)and weights from 7 to 28kgs (16.4±5.8 kgs). The ultrafiltrator was interposed in the port of arterial filter of the CPB circuit and performed during the rewarming period. Ultrafiltration blood flow rate was 250-300 ml/ min and negative pressure was less than -250 mmHg. The average ultrafiltrability (total blood flow volume/ultrafiltration fluid volume) was 11.2%(10.7-12.1%). After ultrafiltration HCT increased from 16.1 %(15-18%) to 34.7%(32-40%). In the ICU, 5 cases (TOF 3, VSD 1 and ASD 1) had hemoglobinuria. The indications of ultrafiltration in pediatric cardiac surgery are: 1. The initial perfusion is conducted with bloodless priming or with blood priming when the HCT value dropped to lower than 17% during CPB. 2. The CPB time is longer than 2 hours. 3. The patient receives digoxin and diuretics preoperatively or has complex anomals. Our experience showed that ultrafiltration during pediatric CPB is facile, safe, and effective. It may result in a reduced amount of fluid accumulation in extracellular fluid space with hemodilution perfusion which benefits the patients postoperative recovery. Hemoconcentration of dilute blood during cardiopulmonary bypass(CPB) by plasma water removal is an extracorporeal technique application by ultrafiltration during the pediatric open-heart surgery. Usually after CPB, especially in infant cases, the residual pump blood volume is much more than the acceptable volume for postoperative transfusion. Therefore, the transfusing of large volumes of dilute blood with low colloid oncotic pressure to the patient may cause circulatory overload with normovolumic anemia and result in significant fluid diffusion into interstitial space. In order to save the residual pump blood and reduce such ill effects and complications, we applied ultrafiltration on 40 pediatric cases during open-heart surgical procedures. Our clinical data, ultrafiltration application indications and recommended procedures are now presented.
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Ming, Zhu De, Wang Wei, Chen Hong, Zhang Wei, and Ding Wen Xiang. "Balanced Ultrafiltration, Modified Ultrafiltration, and Balanced Ultrafiltration with Modified Ultrafiltration in Pediatric Cardiopulmonary Bypass." Journal of ExtraCorporeal Technology 33, no. 4 (December 2001): 223–26. http://dx.doi.org/10.1051/ject/2001334223.

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This study evaluates the effect of balanced ultrafiltration, modified ultrafiltration, and balanced ultrafiltration with modified ultrafiltration on inflammatory mediators in children’s open-heart surgery. Eighty children with congenital heart disease were randomly divided into four groups: control group (C group); balanced ultrafiltration group (BUF group); modified ultrafiltration group (MUF group); and balanced ultrafiltration with modified ultrafiltration group (B+M group). Clinical data of these groups were similar. Tumor necrosis factor (TNF), interleukin-8(IL-8), and E-selectin were measured at the beginning of cardiopulmonary bypass (CPB), 30 min later, at the cessation of CPB, at the cessation of MUF (MUF group and B+M group), and 2 hours postoperatively. During CPB, the concentrations of TNF, IL-8, and E-selectin increased significantly in C and MUF groups and did not change significantly in BUF and B+M groups. In the period of MUF, TNF and IL-8 increased; whereas, Eselectin did not change. The study shows that ultrafiltration can filter out the inflammatory mediators, but only BUF can decrease the concentrations of them. Moreover, MUF only can concentrate blood. Combining both techniques has both effects, but the effect of BUF was offset by MUF.
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Soat, Marian. "Ultrafiltration." Nursing Management (Springhouse) 39, no. 1 (January 2008): 48–49. http://dx.doi.org/10.1097/01.numa.0000305993.07980.51.

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Bourge, Robert C., and José A. Tallaj. "Ultrafiltration." Journal of the American College of Cardiology 46, no. 11 (December 2005): 2052–53. http://dx.doi.org/10.1016/j.jacc.2005.09.014.

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Babka, Ronald M., James Petress, Richard Briggs, Robert Helsel, and John Mack. "Conventional haemofiltration during routine coronary bypass surgery." Perfusion 12, no. 3 (May 1997): 187–92. http://dx.doi.org/10.1177/026765919701200307.

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The use of conventional ultrafiltration during cardiopulmonary bypass (CPB) has been well recognized as an efficient modality of therapy to reverse the effects of deliberate haemodilution. Routine use of the haemofilter was prospectively studied on 60 patients undergoing coronary artery bypass surgery. Group A consisted of 30 patients on whom the ultrafiltrator was used and compared to group B who did not receive the ultrafiltration technique. The COBE 1200 ultrafiltration device was used. The results of the study demonstrated that, in group A, the mean total amount of ultrafiltrate collected during bypass was 2510 ± 804 ml per patient. The mean 24-h postoperative blood loss was 440 ± 192 ml in group A and 451 ± 136 ml in group B. The average bank blood transfused was 0.6 ± 1.3 units per patient in group A and 0.75 ± 1.5 units per patient in group B. Postoperative weight gain in group A averaged 3.5 ± 3.45 lb per patient, compared to 4.8 ± 3.7 lb per patient in group B. Postoperative length of stay averaged 6.4 ± 1.5 days per patient in group A and 6.4 ± 2.1 days per patient in group B. Overall patient charges averaged $33 706 ± 8348 per patient in group A and $33 041 ± 7674 per patient in group B. It was concluded that routine use of ultrafiltration during routine coronary artery bypass surgery with CPB offers no improvement in the quality of care nor does it decrease the patient’s overall charges.
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Babenyshev, S. P., V. E. Zhidkov, D. S. Mamay, V. P. Utkin, and N. A. Shapakov. "ULTRAFILTRATION OF MODIFIED MILK WHEY." Food and Raw Materials 4, no. 2 (December 30, 2016): 101–10. http://dx.doi.org/10.21179/2308-4057-2016-2-101-110.

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Lazarev, Sergey I., Yuri V. Golovin, Irina V. Khorokhorina, Sergey V. Kovalev, and Alexandr A. Levin. "KINETIC AND STRUCTURAL CHARACTERISTICS OF ULTRAFILTRATIONAL MEMBRANES AT SEPARATION OF SOLUTIONS CONTAINING SODIUM LAURYLSULPHATE." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 62, no. 10 (October 29, 2019): 89–95. http://dx.doi.org/10.6060/ivkkt.20196210.6031.

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In work the generalized analysis of literary data on a research of relative permeability ratio of various types of porous organic and inorganic membranes was submitted. Application of a method of X-ray analysis of samples of the semipermeable ultrafiltrational membranes on a diffractometer of DRON-3 and a specific output flow on a flat-chamber ultrafiltration unit is shown. In materials of work the pilot and theoretical studies on isokinetic zones and structural characteristics of polymeric semipermeable membranes in the course of ultrafiltrational separation of the technological solutions containing the anionic and fissile surface substances are conducted. It is experimentally confirmed that kinetic curves on a specific output flow have two isokinetic zones. The first zone, the stage of the ultrafiltration process, proceeds quickly, lasts only a few minutes - 7.8 min and 13.05 min, the second zone is slower with duration of about 30 min and 60 min for ultrafiltration cellulose acetate membranes of the UAM-100 and UAM-50 series, respectively. The revealed isokinetic zones differ in characteristic times, which differ by orders of magnitude, and, as a result, the final kinetic dependence has an exponential form. The comparative analysis of roentgenograms allows to note coincidence of angles of diffraction, but significant redistribution of intensity of reflexes in air-dried and working sapless in the range of scattering angles 2θ from 8°-35°. The obtained experimental data and their comparison with literary, indicate the same set of the diffraction reflexes at corners 2θ = 17°; 22°; 25° for both samples of membranes that corresponds to the crystal reflexes of membranes created from polyamide fibers (nylon).
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Liu, Shu Xing, and Bei Wang. "Purification of Ferulic Acid from Wheat by Ultrafiltration Technology." Advanced Materials Research 524-527 (May 2012): 2294–97. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.2294.

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Purification extraction of ferulic acid from wheat bran by using ultrafiltration,based on the molecular weight cutoff (MWCO) of ultrafiltration membranes,ultrafiltration pressure,sample concentration,ultrafiltration time these four factors influence of the membrane flux,determine the best the ultrafiltration conditions.
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Dissertations / Theses on the topic "Ultrafiltration"

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Vaidya, A. M. "Ultrafiltration modelling." Thesis, University of Manchester, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.237688.

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Rakotoarisoa, Herivola Henri. "Influence d'un promoteur de turbulence fluidisé en ultrafiltration et électro-ultrafiltration." Grenoble INPG, 1986. http://www.theses.fr/1986INPG0107.

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Les membranes utilisees sont des membranes minerales. Pour l'ultrafiltration, la fluidisation permet d'ameliorer notablement les debits de permeation sans qu'il y ait pour autant deterioration de la retention en macromolecules. Mise en evidence de conditions optimales de porosite du lit fluidise. L'action des particules fluidisees est moins significative pour l'electroultrafiltration
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Ghosh, Raja. "Protein fractionation using ultrafiltration." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302133.

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BANZI, ALBERT. "Concentration de lactoserum par ultrafiltration." Toulouse 3, 1986. http://www.theses.fr/1986TOU30042.

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Ce travail concerne la conception et le controle d'installations destinees a concentrer du lactoserum doux par ultrafiltration sur membranes minerales. Une etude bibliographique met en evidence la necessite d'etablir des lois reliant le transfert de matiere aux conditions operatoires (pression, regime hydrodynamique, concentration, geometrie de membrane). Ces lois sont etablies empiriquement en utilisant divers lactoserums et des solutions de concentrats de proteines. Deux methodologies experimentales (pression constante ou pression variable, a concentration constante) sont envisagees. Enfin, l'etude du fonctionnement d'une boucle de concentration a l'echelle du laboratoire est menee et les resultats compares a un modele integrant les lois de transfert empiriques determinees precedemment. Le bon accord entre les calculs et les resultats experimentaux permet d'utiliser le modele pour analyser l'influence des caracteristiques de l'installation (volume mort, surface de membrane) sur le temps de mise en regime des installations
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Banzi, Albert. "Concentration du lactosérum par ultrafiltration." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37595695f.

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Farzanehsa, Seyedeh Zahra. "Decolourisation of Molasses by Ultrafiltration." Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/18596.

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Molasses is a dark brown by-product of sugar production and refining, rich in sugar, vitamins, and salts. The dark coloured pigments are mainly melanoidins, which are produced through the Maillard reaction between amino acids and sugar. Molasses is widely used as an inexpensive source of sugar in biorefineries to produce a range of products including baker’s yeast. Due to adsorption of melanoidins, Baker’s yeast has a dark colour and needs to be washed in several steps to be acceptable to the market. This washing increases the volume of wastewater, which causes major wastewater treatment issues. Ultrafiltration of molasses has been proposed to minimise the need for downstream washing processes, by removing the coloured compounds, whilst also sterilising the molasses prior to fermentation. The ultrafiltration of molasses poses a number of scientific questions and technical challenges. In particular; what is the fouling mechanism of molasses? What determines the sugar retention in such systems? In addition, what is the optimal membrane for molasses decolourisation? The approach used in this thesis is to systematically investigate the following areas: (1) membrane characterisation; (2) molasses characterisation; (3) investigating the effect of operating conditions on ultrafiltration; (4) investigating modelling of fouling and optimising the cleaning procedure i.e. the interaction of three other areas (5) modelling of cane and beet molasses ultrafiltration to select the optimal membrane. The literature review found that the prior research has generally been limited with regards to the effect of membrane materials on ultrafiltration of molasses or other sugar streams. Previous researchers have typically used a single type of molasses and a small number of membranes. In addition, most of the limited existing literature has focused on the relationship between the manufacturers specified Molecular Weight Cut-Off (MWCO) and colour removal from the sugar stream for a single molasses type. Generally, a relationship was found in each single study but these relationships were inconsistent between studies. Therefore, a comprehensive set of experiments was carried out on ultrafiltration of molasses at different operating conditions (5 and 10 bar), with a range of membranes of different MWCO (2-30 kDa), for polysulfone, polyethersulfone, polyacrylonitrile and polyvinylidenedifluoride, on both cane and beet molasses. Two membranes geometries (flat sheet and spiral wound) were also used in ultrafiltration of cane and beet molasses. As molasses characteristics are crucial factors in the ultrafiltration process, six different types of molasses, three beet and three cane, were characterized based on their chemical and physical properties. These properties can vary considerably depending on the type of molasses (cane or beet), the origin of molasses and the production process. These variations are of importance to the bioprocessing industries, which use molasses as a feedstock. Despite this, few authors have examined characteristics relevant to industrial processing such as the viscosity of different types of molasses and only a few studies have investigated colourant molecular weight distribution. This gap has been addressed in the present thesis. To this end, a comprehensive set of experiments was undertaken to characterise molasses with a view to the industrial application of molasses ultrafiltration in baker’s yeast production plant. It was found that cane molasses contains higher amounts of suspended solids compared to beet molasses (11.3-21.5 g/L for cane molasses compared to 6.6-7.8 g/L for beet molasses), accounting for higher sugar retention and rapid fouling during ultrafiltration which was found to be complete pore blocking. In addition, using Liquid Chromatography–Organic Carbon Detection (LC-OCD) method, it was shown that molecular weight distribution of colour pigments in cane molasses is more skewed toward higher molecular weights. The average molecular weight of melanoidins in cane molasses is 2.5 to 3 times higher than melanoidins in beet molasses. As part of this thesis, the effect of operating conditions on ultrafiltration performance was quantified through systematic laboratory experimentation. Changes in permeate flux and its colour and sugar content in relation to changes in the operating conditions was examined for various molasses-membrane combinations. For both beet and cane molasses ultrafiltration 5 kDa flat sheet membrane made of polyethersulfone yielded the highest colour removal (87% for cane molasses and 70% for beet molasses). The effect of increasing pressure from 5 bar to 10 bar was negligible in terms of colour removal. However, it increases the sugar retention by more than 100% (from 10% to 21 % for cane molasses and from 1% to 12% for beet molasses) suggesting different mechanism for sugar/colour separation and a relationship between sugar retention and fouling. These findings provide an opportunity to optimise ultrafiltration process by operating at low pressures. In ultrafiltration of cane molasses, it was found that less hydrophilic membranes (contact angle ~ 75o) tend to show slower fouling and higher colour removal compared to more hydrophilic membranes (~ 37o). In addition, it was found that membranes of the same nominal size (MWCO: molecular weight cut off), can have different pore sizes (Pore size of Alfa Laval 5 kDa membrane is 10.8 nm compared to pore size of Synder 5 kDa membrane which is 8.8 nm) that will affect the permeability of membranes and hence the flux. The fouling mechanism was modelled for the ultrafiltration of cane and beet molasses, using first and second derivatives of flux. It was found that the fouling mechanism for ultrafiltration of cane molasses is complete pore blocking at both 5 and 10 bar. Complete pore blocking in cane molasses ultrafiltration can be attributed to the presence of high amounts of suspended solids in cane molasses (TSS=16.3 g/L) and their large size (>22 µm). A range of different cleaning protocols were tested on spiral wound membranes in order to maintain the durability and efficiency of membranes and keep the maintenance cost of ultrafiltration minimal. A combination of water washing, followed by caustic washing was successful in removing organic fouling. The highest flux recovery of 65% was achieved using this procedure. Higher flux recovery could be potentially achieved by backwashing. However, both membrane manufacturers recommended against backwashing. More trials on molasses ultrafiltration using ceramic membranes could increase the flux recovery. The concluding work of this thesis involved statistical modelling of molasses ultrafiltration that was carried out on cane and beet molasses in order to find the optimal membrane selection for each cane and beet molasses ultrafiltration. It was found that permeate flux for both cane and beet molasses is positively correlated to average pore size of membranes. However, the determining factors in colour removal in cane and beet molasses ultrafiltration are different. In cane molasses due to presence of hydrophobic compounds, hydrophobicity of membranes (i.e. the contact angle) as well as MWCO plays important roles. Colour removal in cane molasses ultrafiltration was positively correlated with contact angle (r=0.906) and negatively with MWCO (r= -0.88). Whilst in beet molasses ultrafiltration, the relationship was not as strong between colour removal and MWCO (r=-0.444). In beet molasses ultrafiltration, a spurious correlation was found between colour removal and average pore size, which was not mechanistically meaningful. In both cane and beet molasses ultrafiltration, flux was exponentially correlated to the average pore size of membranes. It was found that the cause of this was that the optimal tested membrane in terms of maximum colour removal, minimum sugar retention, and highest flux for both cane and beet molasses is polyethersulfone 5 kDa membrane and this was reflected in the results of the statistical models. Now the optimum membrane based on membrane characteristics (MWCO of 5 kDa and 75o contact angle) can be chosen for plant trials. Modelling the system design for ultrafiltration of cane and beet molasses concluded that a three stage ultrafiltration unit, can obtain a sugar recovery of more than 95%. By using ultrafiltration upfront in molasses based industries, energy consumption cost for the wastewater treatment reduced by 84%. Results of this research highlight the significant merit of using ultrafiltration upfront in molasses based industries to overcome wastewater treatment issues in molasses-based industries.
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Ramli, Nor Hanuni. "Ultrafiltration of polydisperse colloidal silica." Thesis, Swansea University, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.678552.

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Demessie, Berhanu. "Ultrafiltration of Partially Degraded Starch Solution." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Natural Sciences and Technology, 2002. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-30.

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Desizing wastewater is largely responsible for the chemical oxygen demand (COD) load in the textile industry wastewater. A larger portion of COD comes from degraded starch in desizing wastewater. Removing the starch from the wastewater by an ultrafiltration process may reduce the environmental problem caused by the textile factory. If the treatment is made in such a way that all starch components are removed from the wastewater, the treated water can be reused by the factory. If the starch in the concentrate is stable, it can also be reused as a sizing agent. This will give the factory an economic advantage.

In this thesis we have studied the fouling mechanisms involved in the ultrafiltration of solution with partially degraded starch in order to find the treatibility of such solutions. The work has mainly been directed to uncover how the different fouling mechanisms depend on the operating parameters, and to find the performance of selected membranes. In addition, different models were evaluated for their validity in predicting the performance of the membranes and the data was fitted to the model that give the best prediction and are physically more meaningful. In addition, the starch solution was concentrated, and the flux, concentration, retention and rejection profiles as a function of concentrating time were investigated.

For the study, we used a partially degraded starch solution as a model solution. The solution was prepared in the laboratory by enzymatic degradation of potato starch to different levels. In order to evaluate the reproducibility of the degraded starch, three replicates were prepared. The reproducibility was determined by comparing the molar mass distribution from HPLSEC analysis and the concentration of reducing sugar from a DNS test for the replicates. The analyses show very good reproducibility. Three starch model solutions with three different degradation levels were chosen for our ultrafiltration experiments to investigate the effect of average molar mass of the starch.

For the ultrafiltration of the solution ES625 (from PCI) and MPT-U20 (from KOCH) membranes were used. Both membranes were used in the investigation of the contribution of different fouling mechanisms to the flux decline during ultrafiltration of the solution. In the evaluation of the performance of ultrafiltration of the starch solution, however, only the ES625 membrane was used. According to the manufacturers, both membranes have nearly equal pure water flux and MWCO. But in our test, we observed a higher and different pure water flux for each type of membrane. The ES625 had a lower flux (higher retention) than the MPTU20 membrane.

In the ultrafiltration of partially degraded starch solution the permeate flux declines very fast and, for a low feed concentration, it reaches a steady state in a very short time. The steady state time was observed to increase with concentration, molar mass and transmembrane pressure drop, and to decrease with cross flow velocity. All the three fouling mechanisms (concentration polarization, adsorption and deposition) were responsible for the flux decline. The major observed contributors are, however, adsorption and deposition. Adsorption is largely responsible at low-pressure operation while the deposition fouling effect is dominant at higher pressures, near or beyond the limiting flux.

For the ES625 membrane, the contribution of adsorptive fouling increases with concentration and decreases with molar mass of the starch, temperature and pH at a given transmembrane pressure and cross flow velocity. The effect of the operating parameters on the depositional fouling is in line with literature. It increases with pressure, concentration, molar mass and temperature, and decreases with cross flow velocity. Its dependence on pressure can be expressed by a power function with exponent larger than 1.0. This seems to due to an increase in thickness and compaction of the starch gel/deposit at the membrane surface as the transmembrane pressure drop is increased. The contribution of the concentration polarization is also dependent on concentration, cross flow velocity and pressure. Its relative contribution increases with concentration while it decreases with an increase in cross flow velocity. In the turbulent flow regime the relation between the resistance contributed by concentration polarization increases almost linearly with transmembrane pressure drop. In the laminar flow regime, however, the relative contribution of the resistance due to concentration polarization increases for the lower range of pressure and decreases for the higher range of pressure. Its relative contribution also increases with temperature and decreases with increasing molar mass. But the overall fouling resistance in the ultrafiltration of the starch solution increases with feed concentration, molar mass of the starch and transmembrane pressure drop and decreases with cross flow velocity and temperature.

The trend of the flux loss due to all fouling mechanisms for MPT-U20 membrane is similar to ES625 membrane except for adsorption and concentration polarization with changes in concentration and molar mass. The difference could be a result of the difference in morphological properties between the two membranes and the experimental procedures used in determining flux data that used for calculating the contributions. From the pure water flux and the retention data, the ES625 membrane seemed to have a smaller pore size than the MPT-U20 membrane.

Among the ultrafiltration models, the resistances-in-series model was chosen for its provision to include all the fouling mechanisms into the model. When our permeate flux data was fitted to the model, it gives a good fit. However, the model fails to give realistic estimates of the contribution of the individual fouling mechanisms. In order to improve this problem, the model was modified by introducing osmotic pressure across the membrane in such a way that the effect of concentration polarization is accounted for. This modified model is more physically meaningful and gives a realistic estimate of the contribution the reversible and irreversible fraction of the overall resistance.

In concentrating mode operation, the permeate was continuously withdrawn and hence, the concentration of starch in the feed tank was increased. At an early stage of ultrafiltration, the permeate flux appeared to increase slightly, which seems, a result a shear thinning of the starch solution when the solution was pumped through the system. For the rest of the operation, the flux was decreasing, the retention was increasing and the rejection of the membrane was shifted to a lower molar mass as the solution in the feed tank got more concentrated as expected. The shift of rejection to the lower molar mass region is due to the fouling layer that reduces the accessibility of the pores of the membrane.

Generally, the flux we obtained in ultrafiltration of a partially degraded starch solution with the ES625 tubular membrane is equal or better than the reported values from an existing ultrafiltration plant that has been used in the textile industry to recover a synthetic sizing agent (PVA) from the desizing wastewater. The retention is, however, rather low. Two or more stages of treatment are needed to get all starch components removed from the wastewater and make the treated water reusable (recycled).

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Turkson, Abraham K. "Electro-ultrafiltration with rotating dynamic membranes." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=72036.

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In axial electrofiltration, a DC electric field is imposed between a rotating inner cylinder and a stationary outer cylinder giving rise to four mechanisms which act to minimize solute accumulation at the filter surface: turbulence, centrifugal force, electrophoresis and shear stress which removes solute aggregates.
Four dynamic membranes, Zr(IV) oxide, calcium oleate, poly-2-vinylpyridine and cadmium sulfide, were used to filter bovine serum albumin (BSA) in a disodium phosphate solution at pH = 8 and Prussian blue in distilled water. Prussian blue is a particle of 0.01(mu)m diameter with a zeta potential of -41mV while BSA is a macromolecule of 69,000 molecular weight, a Stokes-Einstein radius of 0.0038(mu)m and a zeta potential of -23.3mV at pH = 8. For BSA, the flux declined with time while the rejection increased. Filtrate fluxes increased with rotation rate and electric field and declined with concentration for both feeds. The flux declined beyond N = 2000rpm and was constant above C(,0) = 5.0wt%. For Prussian blue, the rejection was greater than 90% at all levels of E, N and C(,0). For BSA, the rejection increased with rotation rate and declined with concentration. The BSA rejection declined above N = 2000rpm and was constant beyond C(,0) = 0.5wt%.
A mathematical model was derived to predict the time variation of filtrate flux and a rejection model was used to predict the effect of surface concentration on BSA rejection.
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Vasan, S. S. "Analysis of mass transfer in ultrafiltration." Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.424738.

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Books on the topic "Ultrafiltration"

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Sourirajan, S., and Takeshi Matsuura, eds. Reverse Osmosis and Ultrafiltration. Washington, D.C.: American Chemical Society, 1985. http://dx.doi.org/10.1021/bk-1985-0281.

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Munir, Cheryan, ed. Ultrafiltration and microfiltration handbook. Lancaster, Pa: Technomic Pub. Co., 1998.

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S, Sourirajan, Matsuura Takeshi 1936-, American Chemical Society. Division of Industrial and Engineering Chemistry., and American Chemical Society Meeting, eds. Reverse osmosis and ultrafiltration. Washington, D.C: American Chemical Society, 1985.

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1936-, Matsuura Takeshi, and National Research Council Canada, eds. Reverse osmosis, ultrafiltration process principles. Ottawa, Canada: National Research Council Canada, 1985.

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Sourirajan, S. Reverse osmosis/ultrafiltration process principles. Ottawa, Canada: National Research Council Canada, 1985.

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Sourirajan, S. Reverse osmosis: Ultrafiltration process principles. Ottawa, [Ontario]: National Research Council Canada, 1985.

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Hanft, Susan. Ultrafiltration membrane industry: Developments, markets. Norwalk, CT: Business Communications Co., 2002.

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Banzi, Albert. Concentration du lactoserum par ultrafiltration. Grenoble: A.N.R.T, Université Pierre Mendes France (Grenoble II), 1986.

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Sourav, Mondal, ed. Micellar enhanced ultrafiltration: Fundamentals & applications. Boca Raton, FL: Taylor & Francis, 2012.

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Bryk, M. T. Ulʹtrafilʹtrat͡s︡ii͡a︡. Kiev: Nauk. dumka, 1989.

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Book chapters on the topic "Ultrafiltration"

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Xirouchaki, Nektaria, Dimitrios Georgopoulos, Keith Boniface, Venkatesh Bellamkonda-Athmaram, Lindsay E. Nicolle, Sean M. Bagshaw, Ambica Parmar, et al. "Ultrafiltration." In Encyclopedia of Intensive Care Medicine, 2345. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-00418-6_3359.

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Lin, S. Y. "Ultrafiltration." In Methods in Lignin Chemistry, 518–23. Berlin, Heidelberg: Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-74065-7_37.

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Aptel, Philippe, and Michael Clifton. "Ultrafiltration." In Synthetic Membranes: Science, Engineering and Applications, 249–305. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-4712-2_10.

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Shrikhande, A. J., and S. A. Kupina. "Ultrafiltration." In ACS Symposium Series, 197–218. Washington, DC: American Chemical Society, 1993. http://dx.doi.org/10.1021/bk-1993-0536.ch011.

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Gooch, Jan W. "Ultrafiltration." In Encyclopedic Dictionary of Polymers, 930. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-6247-8_15044.

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Mishra, Munmaya, and Biao Duan. "Ultrafiltration." In The Essential Handbook of Polymer Terms and Attributes, 246–47. Boca Raton: CRC Press, 2024. http://dx.doi.org/10.1201/9781003161318-229.

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Lutz, Herb. "Ultrafiltration (UF)." In Encyclopedia of Membranes, 1947–48. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-44324-8_1206.

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Lutz, Herb. "Ultrafiltration Applications." In Encyclopedia of Membranes, 1948–49. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-44324-8_1207.

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Duke, Mikel, and Todor Vasiljevic. "Whey Ultrafiltration." In Encyclopedia of Membranes, 2035–36. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-44324-8_2053.

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Mujais, S., and W. Smit. "Ultrafiltration Failure." In Nolph and Gokal’s Textbook of Peritoneal Dialysis, 505–22. Boston, MA: Springer US, 2009. http://dx.doi.org/10.1007/978-0-387-78940-8_17.

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Conference papers on the topic "Ultrafiltration"

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Jordhamo, George M., Ian Melville, and Ann M. Mewherter. "Photoresist ultrafiltration optimization." In 23rd Annual International Symposium on Microlithography. SPIE, 1998. http://dx.doi.org/10.1117/12.312475.

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Bilstad, T., E. Espedal, A. H. Haaland, and M. Madland. "Ultrafiltration of Oily Wastewater." In SPE Health, Safety and Environment in Oil and Gas Exploration and Production Conference. Society of Petroleum Engineers, 1994. http://dx.doi.org/10.2118/27136-ms.

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Zhou, Nina, and A. G. Agwu Nnanna. "Parametric Study of Ultrafiltration." In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-11696.

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The performance of cross flow hollow fiber ultrafiltration (UF) membrane with molecular weight cut off (MWCO) 100 kDaltons was studied in order to effectively remove suspended solids in wastewater. Experiments were carried out to investigate the influence of the several factors such as cross flow velocity, transmembrane pressure (TMP), water temperature, and concentration of suspended solids on the membrane performance. Several cleaning methods were applied to remove the fouling. The experimental results showed that increasing TMP, temperature and cross flow velocity all resulted in increasing permeate flux. It is observed that high TMP aggravated the fouling while high cross flow velocity alleviated the fouling. High concentrations of suspended solids led to the reduction of permeate flux. It is also found that both combination of chemical, back- and forward-washing as well as soaking cleaning methods effectively removed fouling and achieved high flux recovery. The suspended solids were effectively removed by our UF system, and the water quality is significantly improved after ultrafiltration.
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Duignan, Mark R., and Si Y. Lee. "Cross-Flow Ultrafiltration Scaling Considerations." In ASME 2006 2nd Joint U.S.-European Fluids Engineering Summer Meeting Collocated With the 14th International Conference on Nuclear Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/fedsm2006-98492.

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One legacy of the nuclear age is radioactive waste and it must be stabilized to be stored in a safe manner. An important part of the stabilization process is the separation of radioactive solids from the liquid wastes by cross-flow ultrafiltration. The performance of this technology with the wastes to be treated was unknown and, therefore, had to be obtained. However, before beginning a filter study the question of experimental scale had to be addressed. Of course, carrying out experiments using full-size equipment is always ideal, but rarely practical when dealing with plant size processes. Flow loops that will handle millions of liters of slurries, which are either highly caustic or acidic, with flow rates of 10,000 lpm make full-scale tests prohibitively expensive. Moreover, when the slurries happen to be radioactive such work is also very dangerous. All of these considerations lend themselves to investigations at smaller scales and in many situations can be treated with computational analyses. Unfortunately, as scale is reduced it becomes harder to provide prototypic results and the two and three phase multi-component mixtures challenge accurate computational results. To obtain accurate and representative filter results two smaller scale filters were chosen: 1. Small-scale – would allow the testing with actual radioactive waste samples and compare results with simulated wastes that were not radioactive. For this scale the feed tank held 6 liters of waste and it had a single cross-flow filter tube 0.61 m long. 2. Pilot-scale – would be restricted to use simulated non-radioactive wastes. At this larger scale the feed tank held 120 liters of waste and the filter unit was prototypic to the planned plant facility in pore size (0.1 micron), length (2.29 m), diameter (0.0127 m inside and 0.0159 m outside diameter), and being multi-tubed. The small-scale apparatus is convenient, easy to use, and can test both radioactive and non-radioactive wastes; therefore, there is a larger database than at the pilot scale. In fact, the small-scale data are very useful to compare actual waste to simulated waste filter performance to validate a simulant, but data availability does not mean they accurately represent full-scale performance. Results indicate that small-scale filter fluxes to be significantly higher that those at the pilot scale. In an attempt to study the difference in filter performance at the two scales an experiment was done that used exactly the same simultant which was created at the same time so that issues of composition and aging would not compromise the results. This paper will discuss those experimental results, as well as those from a computational fluid dynamics model to better understand the small-scale limitations.
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Aryanti, Nita, Vania Frimasgita Giraldi, Heru Susanto, Tutuk Djoko Kusworo, I. Nyoman Widiasa, and Nur Rokhati. "Model of fouling mechanism in ultrafiltration and micellar-enhanced ultrafiltration membrane for reactive dye removal." In THE 2ND INTERNATIONAL SYMPOSIUM OF INDONESIAN CHEMICAL ENGINEERING 2021: Enhancing Innovations and Applications of Chemical Engineering for Accelerating Sustainable Development Goals. AIP Publishing, 2023. http://dx.doi.org/10.1063/5.0118033.

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Das, Supriyo, Elbir Jové Alvarez, and Neville Lange. "Offshore Ultrafiltration with Multi Element Vessels." In Offshore Technology Conference. Offshore Technology Conference, 2016. http://dx.doi.org/10.4043/27116-ms.

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Kresnowati, M. T. A. P., Ria Desiriani, and I. G. Wenten. "Ultrafiltration of hemicellulose hydrolysate fermentation broth." In ENGINEERING INTERNATIONAL CONFERENCE (EIC) 2016: Proceedings of the 5th International Conference on Education, Concept, and Application of Green Technology. Author(s), 2017. http://dx.doi.org/10.1063/1.4976888.

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Farnand, Brian, and Tom Krug. "Oilfield Produced Water Treatment By Ultrafiltration." In Technical Meeting / Petroleum Conference of The South Saskatchewan Section. Petroleum Society of Canada, 1987. http://dx.doi.org/10.2118/ss-87-15.

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Shanti Bhushan and Mark R Etzel. "Charged Ultrafiltration Membranes for Protein Separation." In 2007 Minneapolis, Minnesota, June 17-20, 2007. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2007. http://dx.doi.org/10.13031/2013.22870.

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Aosai, Daisuke, Yuhei Yamamoto, and Takashi Mizuno. "Development of New Ultrafiltration Techniques Maintaining In-Situ Hydrochemical Conditions for Colloidal Study." In ASME 2010 13th International Conference on Environmental Remediation and Radioactive Waste Management. ASMEDC, 2010. http://dx.doi.org/10.1115/icem2010-40074.

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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.
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Reports on the topic "Ultrafiltration"

1

Steffani, C., and M. Meltzer. Alkaline detergent recycling via ultrafiltration. Office of Scientific and Technical Information (OSTI), June 1995. http://dx.doi.org/10.2172/104336.

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Farnand, B., and T. Krug. Oilfield produced water treatment by ultrafiltration. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1987. http://dx.doi.org/10.4095/302687.

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Scamehorn, J., and S. Christian. A study of micellar-enhanced ultrafiltration. Office of Scientific and Technical Information (OSTI), November 1989. http://dx.doi.org/10.2172/5554436.

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Russell, Renee L., Justin M. Billing, Reid A. Peterson, Donald E. Rinehart, and Harry D. Smith. Development and Demonstration of Ultrafiltration Simulants. Office of Scientific and Technical Information (OSTI), February 2009. http://dx.doi.org/10.2172/963208.

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Weisbrod, K. R., A. R. Schake, A. N. Morgan, G. M. Purdy, H. E. Martinez, and T. O. Nelson. Ultrafiltration evaluation with depleted uranium oxide. Office of Scientific and Technical Information (OSTI), March 1998. http://dx.doi.org/10.2172/658159.

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Smiley, G. T., and H. Dettman. Analysis of ultrafiltration permeate (centrifuged produced water sample). Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1991. http://dx.doi.org/10.4095/304487.

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Sedath, R. H., S. F. Yates, and N. N. Li. Reduced fouling of ultrafiltration membranes via surface fluorination. Office of Scientific and Technical Information (OSTI), March 1993. http://dx.doi.org/10.2172/6695060.

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Zamecnik, J. R. AN-102 Simulant Sr/TRU Precipitation and Ultrafiltration. Office of Scientific and Technical Information (OSTI), April 2003. http://dx.doi.org/10.2172/810556.

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Sedath, R. H., S. F. Yates, and N. N. Li. Reduced fouling of ultrafiltration membranes via surface fluorination. Office of Scientific and Technical Information (OSTI), March 1993. http://dx.doi.org/10.2172/10130600.

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N. R. Mann, R. S. Herbst, T. G. Garn, M. R. Poirier, and S. D. Fink. Alternative Ultrafiltration Membrane Testing for the SRS Baseline Process. Office of Scientific and Technical Information (OSTI), June 2004. http://dx.doi.org/10.2172/911211.

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