Добірка наукової літератури з теми "Sp-filtration"

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Статті в журналах з теми "Sp-filtration"

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Crabb, M. C., and S. A. Mitchell. "The loops onU(n)/O(n) andU(2n)/Sp(n)." Mathematical Proceedings of the Cambridge Philosophical Society 104, no. 1 (July 1988): 95–103. http://dx.doi.org/10.1017/s0305004100065269.

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In [6] and [9] the second author and Bill Richter showed that the natural ‘degree’ filtration on the homology of ΩSU(n) has a geometric realization, and that this filtration stably splits (as conjectured by M. Hopkins and M. Mahowald). The purpose of the present paper is to prove the real and quaternionic analogues of these results. To explain what this means, consider the following two ways of viewing the filtration and splitting for ΩSU(n). Whenn= ∞, ΩSU=BU. The filtration isBU(1)⊆BU(2)⊆… and the splittingBU≅ V1≤<∞is a theorem of Snaith[14]. The result for ΩSU(n) may then be viewed as a ‘restriction’ of the result forBU. On the other hand there is a well-known inclusion ℂPn−1. This extends to a map ΩΣℂPn−1→ΩSU(n), and the filtration (or splitting) may be viewed, at least algebraically, as a ‘quotient’ of the James filtration (or splitting) of ΩΣℂPn−1. It is now clear what is meant by the ‘real and quaternionic analogues’. In the quaternionic case, we replaceBUbyBSp=Ω(SU/SP), ΩSU(n) by Ω(SU(2n)/SP(n))and ℂPn−1by ℍPn−1. The integral homology of Ω(SU(2n)/SP(n)) is the symmetric algebra on the homology of ℍPn−1, and may be filtered by the various symmetric powers. We show that this filtration can be realized geometrically, and that the spaces of the filtration are certain (singular) real algebraic varieties (exactly as in the complex case). The strata of the filtration are vector bundles over filtrations of Ω(SU(2n−2)/SP(n−1)), and the filtration stably splits. See Theorems (1·7) and (2·1) for the precise statement. In the real case we replaceBUby Ω(SU/SO), Ω(SU(n)/SO(n)) and ℂPn−1by ℝPn−1. Here integral homology must be replaced by mod 2 homology, and splitting is only obtained after localization at 2. (Snaith's splitting ofBOin [14] can be refined [2, 8] so as to be exactly analogous to the splitting ofBU:BO≅V1≤<∞MO(k).)
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Brower, James C. "Systematics and paleoecology of Haptocrinus buttsi, a new species of disparid crinoid from the Upper Ordovician Hatter Limestone of central Pennsylvania." Journal of Paleontology 82, no. 3 (May 2008): 576–84. http://dx.doi.org/10.1666/07-098.1.

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Three crinoids are known from the Upper Ordovician Hatter Limestone at Union Furnace in central Pennsylvania, i.e., Haptocrinus buttsi n. sp., an unknown crinoid with a lichenocrinid holdfast, and an indeterminate columnal that probably belongs to a crinoid. Two crowns enable H. buttsi n. sp. to be reconstructed. The animal lived about 70 cm above the seafloor and was attached to a strophomenid brachiopod with a lichenocrinid holdfast. Its endotomous arms formed an efficient filtration net that covered much of the water within its planar filtration fan. The application of filtration theory indicates that H. buttsi n. sp. could begin to feed at a comparatively low ambient current velocity and balance its energy budget. Like many other ramulate disparids, H. buttsi n. sp. mainly collected moderately small food particles. As a member of the Tornatilicrinidae, H. buttsi n. sp. is a relatively primitive disparid. Another crinoid taxon bears a longer and thinner stem and a different type of lichenocrinid holdfast cemented to the same strophomenid shell. A third species, most likely a crinoid, is represented by a single columnal. The fauna lived in a quiet water lagoonal area, which is an unusual habitat for Paleozoic crinoids.
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Shevnin, V. A. "IDENTIFICATION OF SELF-POTENTIAL ANOMALIES OF DIFFUSION-ADSORPTION ORIGIN." Moscow University Bulletin. Series 4. Geology, no. 2 (April 28, 2018): 93–98. http://dx.doi.org/10.33623/0579-9406-2018-2-93-98.

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Diffusion and adsorption (DA) potentials are frequently the sources of self-potential anomalies, but they not arouse such practical interest as anomalies of red-ox and filtration origin. DA anomalies can be found everywhere and geophysicists sometimes make mistakes considering DA anomalies as examples of filtration anomalies. Identification of DA anomalies is based on correlation of SP and apparent resistivity values along the same profiles. At MSU students geophysical practice in Kaluga region we obtained profiles with SP and resistivity anomalies with good correlation between them. That fact allows consider such SP anomalies as a result of DA processes.
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Kim, Dong-Yeon, Taewoon Hwang, You-Kwan Oh, and Jong-In Han. "Harvesting Chlorella sp. KR-1 using cross-flow electro-filtration." Algal Research 6 (October 2014): 170–74. http://dx.doi.org/10.1016/j.algal.2014.10.004.

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Ding, Linxian, Taketo Hirose, and Akira Yokota. "Amycolatopsis echigonensis sp. nov. and Amycolatopsis niigatensis sp. nov., novel actinomycetes isolated from a filtration substrate." International Journal of Systematic and Evolutionary Microbiology 57, no. 8 (August 1, 2007): 1747–51. http://dx.doi.org/10.1099/ijs.0.64791-0.

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The taxonomic position of two actinomycete strains, LC2T and LC11T, isolated from a filtration substrate made from Japanese volcanic soil, was determined using a polyphasic approach. The strains grew at temperatures from 5 to 45 °C, on media of pH between 6 and 11 and in the presence of 7 % NaCl. The major menaquinone was MK-9(H4). The major fatty acid was iso-C16 : 0. A phylogenetic tree based on 16S rRNA gene sequences showed that the two strains formed a distinct evolutionary lineage within the genus Amycolatopsis. On the basis of their morphological, physiological and genotypic characteristics, the isolates are proposed to represent two novel species of the genus Amycolatopsis, for which the names Amycolatopsis echigonensis sp. nov. (type strain LC2T =IAM 15387T =CCTCC AB206019T), and Amycolatopsis niigatensis sp. nov. (type strain LC11T =IAM 15388T =CCTCC AB206020T) are proposed.
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Afifi, Azzam, Abdel-Aziz Ahmed, Yassir Sulieman, Zakaria Mohamed, and Theerakamol Pengsakul. "EVALUATION OF SOME MICROSCOPIC TECHNIQUES FOR DETECTING BILHARZIA AND INTESTINAL PARASITES." International Journal of Research -GRANTHAALAYAH 4, no. 7 (July 31, 2016): 185–95. http://dx.doi.org/10.29121/granthaalayah.v4.i7.2016.2611.

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The objective of the present study was to evaluate the efficacy of five different diagnostic techniques (haematouria, macro-haematouria, syringe filtration, vacuum flask filtration and sedimentation) in the detection of urinary schistosomiasis. Likewise, five techniques (direct smear, cellophane thick smear, ether-formalin, modified Kato-template and modified Kato-syringe) techniques used in the detection of intestinal schistosomiasis and other intestinal parasites were evaluated using fecal samples. The results showed that the most efficient diagnostic technique for fecal samples is the modified Kato-Katz technique, while the ether-formalin method was the most sensitive tool for the detection of Schistosoma mansoni, Enterobius sp. and Ascaris sp. rates of infection and worm burden. The modified Kato techniques (template and syringe) failed to detect the intestinal protozoa, Giardia lamblia and Entamoeba histolytica, while the syringe filtration technique was the most powerful urine test.
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Kong, Ying Ying, Meng Liu, Wei Di, Cong Wang, Ming Du, and Lan Wei Zhang. "Purification and Identification of Lactoferrin from Bovine Milk." Advanced Materials Research 524-527 (May 2012): 2290–93. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.2290.

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Lactoferrin has many kinds of bioactivities which have attracted more and more attention. In the present study, lactoferrin from bovine milk was isolated and purified by membrane filtration, series of chromatography on SP Sepharose Big Bead ion exchange column and Superdex 200 gel filtration column. The purified lactoferrin was identified by SDS-PAGE compared with the lactoferrin standard.
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Watson, Nikki A., and Klaus Rohde. "Novel Protonephridial Filtration Apparatus in Cylindrostoma fingalianum, Allostoma sp. and Pseudostomum quadrioculatum (Platyhelminthes: Prolecithophora)." Australian Journal of Zoology 45, no. 6 (1997): 621. http://dx.doi.org/10.1071/zo97043.

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The diverse types of protonephridial filtration apparatus in the Platyhelminthes provide valuable characters for phylogenetic resolution, yet only one species from the order Prolecithophora has previously been studied. We examined three further species, two belonging to the family Cylindrostomidae and one from the Pseudostomidae, and found a novel arrangement consisting of scattered, short filtration slits in the cytoplasmic cylinder of the terminal cell surrounding the flame of cilia. In these species there are no regular, longitudinal ‘ribs’, such as are found in many other platyhelminth taxa, nor bundles of supporting microtubules in the cylinder wall, and cilia arise at various levels throughout the long terminal cell column rather than in a group at the base of the flame, as is found in most other taxa. The perikaryon lies adjacent to the flame, the wall surrounding the lumen is strengthened by long, cross-striated ciliary rootlets, and the terminal cell is joined to the proximal canal by a septate junction. This simple type of filtration structure bears some resemblance to that found in Tricladida, but is distinctly different from that described in another prolecithophoran, Archimonotresis limophila (Protomonotresidae). This suggests that there may be a fundamental division within the Prolecithophora with regard to protonephridial filtration structures.
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Nitoda, Teruhiko, Hirokazu Usuki, and Hiroshi Kanzaki. "A Potent Insect Chitinase Inhibitor of Fungal Origin." Zeitschrift für Naturforschung C 58, no. 11-12 (December 1, 2003): 891–94. http://dx.doi.org/10.1515/znc-2003-11-1226.

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Abstract A water-soluble polysaccharide was isolated from the culture filtrate of a fungal strain, Sphaeropsis sp. TNPT116-Cz, as a novel insect chitinase inhibitor. It was purified to chromatographic homogeneity by ethanol precipitation, anion-exchange and gel filtration chromatography. Its molecular weight was estimated to be 16 kDa by gel filtration HPLC. Monosaccharide analysis showed that it contained glucose, galactose, N-acetylglucosamine and a deoxysugar. This polysaccharide showed potent and specific inhibitory activity against Spodoptera litura chitinase with an IC50 value of 28 nᴍ.
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Al-Wasify, Raed S., Mohamed N. Ali, and Shimaa R. Hamed. "Biodegradation of dairy wastewater using bacterial and fungal local isolates." Water Science and Technology 76, no. 11 (September 2, 2017): 3094–100. http://dx.doi.org/10.2166/wst.2017.481.

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Abstract Dairy wastewater contains high levels of organics and other pollutants. The present study was carried out to investigate the biodegradation process of dairy effluents using some locally isolated bacteria and fungi. Four different dairy effluent samples were collected from Obour and 6th October industrial cities, Egypt. Five bacterial species (Pseudomonas aeruginosa, Bacillus subtilis, Lactobacillus delbrueckii, Staphylococcus aureus and Enterococcus hirae) and three fungal strains (Alternaria sp., Fusarium sp. and Aspergillus sp.) were isolated from dairy wastewater samples, identified and used for biodegradation process. Bacterial and fungal consortia were prepared separately in the laboratory. Two-stages (aeration and filtration) laboratory scale model was designed. Rice straw and activated carbon layers were used as filtration media. Results indicated the great ability of both studied bacteria and fungi for removal of organics (biological oxygen demand removal percent were 78.7% and 74.7% for bacteria and fungi, respectively) and the improvement of the physicochemical quality (total suspended solids removal percent were 99.3% and 99.0% for bacteria and fungi, respectively) of the dairy effluent. The addition of rice straw and activated carbon increased removal efficiencies. Biodegradation of dairy wastewater depending on local microorganisms is an effective, cheap and eco-friendly technology.
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Дисертації з теми "Sp-filtration"

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Yamashiro, Sandra 1980. "Monitoramento de cistos de Giardia spp. e oocistos de Cryptosporidium spp. em um manancial eutrofizado com presença de florações de cianobactérias = represa de Salto Grande, Americana-SP." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315669.

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Анотація:
Orientadores: Regina Maura Bueno Franco, Romeu Cantusio Neto
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-16T01:13:52Z (GMT). No. of bitstreams: 1 Yamashiro_Sandra_M.pdf: 8805357 bytes, checksum: 269acfd8ffaefb317f8e7f96a90785f7 (MD5) Previous issue date: 2010
Resumo: O reservatório de Salto Grande é formado pelo rio Atibaia que contribui para a poluição das águas superficiais desta represa, devido ao despejo de efluentes domésticos. Além disso, o desenvolvimento urbano, a industrialização e atividade agrícola nas proximidades da represa, também proporcionam alteração da qualidade das águas deste manancial. Os protozoários gastrointestinais, Giardia spp. e Cryptosporidium spp. estão amplamente presentes em ambiente aquático e suas formas infectantes, cistos e oocistos, são resistentes às condições ambientais (temperatura, radiação solar) e ao processo de desinfecção da água (principalmente à cloração). Inúmeros surtos de gastroenterite foram causados por estes organismos devido à veiculação hídrica sendo que estes protozoários patogênicos tornaram-se uma preocupação constante para os sistemas produtores de água. Os objetivos desta pesquisa foram: verificar a ocorrência de Giardia spp. e Cryptosporidium spp. nas águas superficiais em quatro locais da represa de Salto Grande (Ponto 1: Mini-Pantanal, Ponto 2: Saltinho, Ponto 3: Praia Azul e Ponto 4: Iate Clube) com periodicidade mensal (12 meses); avaliar a qualidade da água mediante análise microbiológica e físico-química deste manancial; comparar a ocorrência destes protozoários nos diferentes pontos (1, 2, 3 e 4); verificar a correlação entre Giardia, Cryptosporidium e os parâmetros analisados; verificar a aplicabilidade do método de filtração em membrana para detecção dos protozoários em um manancial eutrofizado; comparar qualitativamente dois kits comerciais de anticorpos monoclonais para detecção destes agentes parasitários. Para os ensaios parasitológicos, foi empregada a técnica de filtração em membrana de acordo com Franco et al (2001) e visualização mediante reação de imunofluorescência direta com anticorpos monoclonais comerciais; 2) para os ensaios microbiológicos visando a detecção de coliformes totais, termotolerantes e/ou Escherichia coli utilizando as técnicas de tubos múltiplos de acordo com os procedimentos descritos no "Standard Methods" (APHA,AWWA,WEF 2005) e; 3) a contagem de células de cianobactérias foi feita por sedimentação em câmera de Utermöhl, e utilização de microscópio invertido e retículo de Whipple (CETESB, Normalização técnica-NT-06.L5.303,2005). A análise estatística foi realizada com o emprego das técnicas de Análise de Variância, Teste de Comparação Múltipla de Médias (Teste de Duncan), Teste de Qui-Quadrado, Correlação de Pearson com o objetivo de comparar a positividade para os protozoários nos diferentes pontos de coleta e verificar a existência de correlação entre parâmetros biológicos, físico-químicos e parasitológicos das amostras de água do reservatório. De janeiro a dezembro de 2008, 48 amostras de água foram colhidas. Nos pontos 1 e 2, cistos de Giardia foram detectados em 16,6% (326 cistos/L) e 41,6% (785 cysts/L) das amostras, respectivamente. Oocistos de Cryptosporidium foram detectados somente no ponto 2, em 8,3% das amostras (170 cistos/L) enquanto nos pontos 3 e 4 não foram encontrados. A técnica de filtração em membranas apresentou eficiência de recuperação de 8,2% a 34,1% para cistos de Giardia e 5,3% a 8,3% para oocistos de Cryptosporidium (pontos 1 e 2) e para os pontos 3 e 4, as recuperações foram de 42,6% a 88,6% para cistos e 31,9% a 87,5% para oocistos. A separação imunomagnética não resultou em recuperação dos protozoários nas amostras de água que apresentaram floração de cianobactérias (pontos 3 e 4). Nas amostras de água dos pontos 1, 3 e 4, não foram encontradas correlações entre os protozoários e coliformes enquanto no ponto 2, houve correlação entre cistos de Giardia, coliformes termotolerantes e E.coli.
Abstract: The Salto Grande Reservoir is formed by the Atibaia River, that contributes to the pollution of this superficial water reservoir due to the discharge of domestic effluents. In addition, urban development, industrialization, and agricultural activity in the vicinity of the dam also cause degradation in water quality of this watershed. The gastrointestinal pathogenic protozoa Giardia spp. and Cryptosporidium spp are ubiquitous in aquatic environments and their infectious forms, cysts and oocysts, are resistant against environmental conditions (temperature, solar radiation) and water disinfection process (chlorination). Numerous outbreaks of gastroenteritis have been caused by these organisms due to waterborne transmission, and these parasitic protozoa have become a permanent concern in water treatment plants The aims of this study were: to investigate the occurrence of Giardia cysts and Cryptosporidium oocysts in superficial water samples of 4 sites of Salto Grande Reservoir (Point 1: Mini-Pantanal, Point 2: Saltinho, Point 3: Praia Azul and Point 4: Iate Clube) in 12 month period; to assess water quality by microbiological and physical-chemical analysis of water samples from 4 points of this reservoir; to compare the occurrence of these protozoa in different points (1, 2, 3 and 4); to verify the correlation among Giardia, Cryptosporidium and the analyzed parameters; to examine the applicability of the membrane filtration technique for the detection of protozoa in an eutrophic watershed; to qualitatively compare two commercial kits of monoclonal antibodies for detecting these parasites. For parasitological assays, the membrane filter technique according to Franco et al (2001) was employed following visualization by direct immunofluorescence assay (IFA) with commercial monoclonal antibody for enumerating cysts and oocysts in various samples; 2) for microbiological tests aiming the detection of total coliforms, thermotolerant and/or E.coli, the techniques of multiple tubes were used according to the procedures described in "Standard Methods" (APHA, AWWA, WEF, 2005) and 3) cyanobacteria cells counting was performed with Utërmohl Chamber and inverted microscopy and Whipple Grid (CETESB, Normalização técnica-NT-06.L5.303, 2005). Statistical analysis was performed using Analysis of Variance, Multiple Comparisons Test (Duncan's test), Chisquare Test and Pearson Correlation, in order to compare the occurrence of protozoa in different points, and to verify the presence of correlation among biological parameters, physical-chemical, and the presence of parasitic protozoa in water samples from the reservoir. From January to December in 2008, 48 water samples were collected. In points 1 and 2 (Mini-Pantanal e Saltinho), Giardia cysts were detected in 16,6% (326 cistos/L) and 41,6% (785 cysts/L) of the samples, respectively. Cryptosporidium oocysts were detected only in point 2 (Saltinho) in 8,3% (170 oocysts/L) of the samples, while in the others points (3 e 4), both parasites were not detected. The membrane filtration technique attained recovery efficiency range of 8,22% to 34,18% for Giardia cysts and 5,3% to 8,3% Cryptosporidium oocysts (points 1 and 2) and for points 3 and 4, the recoveries efficiency were 42,63% to 88,66% for cysts and 31,97% to 87,5% for oocysts. The immunomagnetic separation did not result in recovering of protozoa in water samples with cyanobacteria blooms (points 3 and 4). In water samples from points 1, 3, and 4, no correlations were found between parasites concentration and coliforms. Water samples from point 2, in contrast, had correlation among Giardia cysts, thermotolerant coliforms, and E.coli.
Mestrado
Parasitologia
Mestre em Parasitologia
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Kakutkina, NA, and MM Mbarawa. "Transition Processes in Filtration Gas Combustion." Plenum Publishing Corporation, 2004. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001750.

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Анотація:
Methane
Summary The behavior of gas filtration combustion waves in the low-velocity regime has been studied experimentally with variation in the parameters of the gas flow and porous medium. It is shown that in transition processes there may be quenching or formation of a stable combustion-wave structure that does not correspond to the initial or final conditions. A nontrivial type of transition process accompanied by spatial transfer of the combustion zone is found.
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Ochieng, GMM, FAO Otieno, TPM Ogada, SM Shitote, and DM Menzwa. "Performance of multistage filtration using different filter media against conventional water treatment systems." Water SA, 2004. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001748.

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Abstract This study was aimed at introducing multistage filtration (MSF) (a combination of slow-sand filtration (SSF) and pretreatment system - horizontal flow roughing filter (HRF)) as an alternative water treatment technology to the conventional one. A pilot- plant study was undertaken to achieve this goal. Evaluating the MSF performance vs. the existing conventional system in removing selected physical and chemical drinking water quality parameters together with the biological water quality improvement by the MSF without chemical use was done. Evaluation of the effectiveness of the MSF system utilizing locally available material, i.e. gravel, improved agricultural waste (charcoal maize cobs) and broken burnt bricks as pretreatment filter material was also done The benchmark was the Kenya Bureau of Standards (KEBS) values for the selected parameters. Results showed that with proper design specifications, MSF systems perform better than conventional systems under similar conditions of raw water quality and environmental conditions. The tested locally available materials can also be effectively used as pretreatment media with each allowing a filter run greater than 82 d and therefore could serve as alternatives where natural gravel is not readily available. With special reference to the bacteriological quality improvement, the MSF greatly improved the bacteriological quality of the water recording removal efficiencies of over 99% and 98% respectively for E. coli and total coliforms. Despite the observed performance, MSF should be complemented with chlorination as a final buffer against water-borne diseases. However, in this case, the dosing will be greatly reduced when compared to the conventional system.
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Mbarawa, M., NA Kakutkina, and Korzhavin AA. "Experimental investigation on peculiarities of the filtration combustion of the gaseous fuel-air mixtures in the porous inertia media." Journal of Mechanical Science and Technology, 2007. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000859.

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This study investigates peculiarities of the filtration combustion (FC) of the gaseous fuel-air mixtures in a porous inertia media (PIM). Combustion wave velocities and temperatures were measured for hydrogen-air, propane-air and methane-air mixtures in the PIM at different mixture filtration velocities. It is shown that the dependences of the combustion wave velocities on the equivalence ratio are V-shaped, It was further confirmed that the FC in the PIM has more contrasts than similarities with the normal homogeneous combustion. One of the interesting observations in the present study, which is not common in normal homogenous combustion, is the shifting of the fuel-air equivalent ratio at the minimum combustion wave velocity from the stoichiometric condition (¢ = 1). For a hydrogen-air mixture, the fuel-air equivalence ratio at the minimum combustion velocity shifts from the stoichiometric condition to the rich region, while for the propane-air and methane-air mixtures the fuel-air equivalence ratio at the minimum combustion velocity shifts toward fuel-leaner conditions. The measured maximum porous media temperatures in the combustion waves are found to be weakly dependent on the mixture filtration velocities. In general, the effects of the mixture filtration velocities on the measured maximum porous media temperatures are not significant.
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Pereira, Glauce Guimarães. "Remoção de células de Microcystis sp por pré-cloração, coagulação, filtração direta e pós-cloração em escala de bancada." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-26072006-091748/.

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Анотація:
Por suas características fisiológicas, cianobactérias se adaptam rapidamente em sistemas eutrofizados e geralmente predominam na comunidade fitoplanctônica. O crescimento excessivo desses microrganismos resulta em dificuldades e acréscimo nos custos do tratamento de água para consumo humano. Além da rápida colmatação dos filtros devido à grande massa orgânica, atribuição de cor e sabor, cianobactérias podem se apresentar tóxicas, liberar na água metabólitos nocivos e também serem precursoras na formação de subprodutos. Assim, este trabalho teve por objetivo avaliar a eficiência de remoção da cianobactéria Microcystis sp por pré-oxidação com cloro, coagulação com sulfato de alumínio, filtração direta e pós-cloração em escala de bancada, baseando-se nos parâmetros de turbidez, contagem celular, distribuição de tamanho e contagem de partículas, carbono orgânico dissolvido e subprodutos organoalogenados. Para atingir tal objetivo foi necessária a realização de experimentos para determinação da dosagem e do tempo de contato de cloro livre e a construção de diagramas de coagulação-filtração. Paralelamente foi determinado o Potencial de Formação de Trialometanos. A presença de cianibactérias não pareceu favorecer a formação de subprodutos indesejados da cloração. O ensaio final foi realizado com pré-cloração, coagulação, filtração e pós-cloração. Para a água pré-clorada com 2,5 mg/L de cloro livre, coagulada com 4 mg/L de sulfato de alumínio comercial, filtrada em areia com tamanho de grãos entre 0,3 a 0,59 mm e pós-clorada com 3,0 mg/Lde cloro livre, a turbidez reduziu de 2,89 para 0,36 uT, redução de 88%. A contagem celular mostrou decréscimo de 99,98% e a contagem de partículas reduziu 96,3% na faixa de tamanho de 3 a 20 \'mü\'m. Também foi observado aumento do carbono orgânico dissolvido com o aumento da dosagem de cloro livre.
Because of their physiological characteristics, cyanobacteria are able to adapt themselves quickly in eutrophic systems and are usually predominant in water bodies. The excessive growth of these organisms results in an increase in water treatment costs and other problems. Beside faster filter clogging due to the large amounts of cyanobacteria, these organisms may be toxic, release toxic metabolites and act as nuisance subproducts precursors. The aim of this work is to evaluate Microcystis sp cyanobacteria removal efficiency by chlorine preoxidation, aluminum sulfate coagulation, direct filtration and post-chlorination in bench-scale experiments. The removal efficiency was evaluated based on turbidity, cell counts, particle size distribution, dissolved organic carbon and halogenated organic subproducts. To reach the objectives it was first necessary to do experiments to determine free chlorine dose and contact time and also prepare coagulation-filtration diagrams. The trihalomethane formation potential was also determined, showing the presence of cyanobacteria did not contribute to subproduct formation. The final test, involving prechlorination, coagulation, filtration and post-chlorination, showed excellent Microcystis sp removal results. For prechlorinated water with 2,5 mg/L of free chlorine, coagulated with 4 mg/L of aluminum sulfate, filtered in a sand bed with grain size between 0,3 and 0,59 mm and post-chlorinated with 3,0 mg/L of free chlorine, turbidity was reduced from 2,89 to 0,36 uT, a 88% decrease. Cell count showed a 99,98% decrease and the particle count was reduced in 96,3% in the size range of 3 to 20 \'mü\'m. An increase in dissolved organic carbon related to the increase in the free chlorine dose was also noted.
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6

Magalhães, Raphaella de Abreu. "Herbivoria de Bosmina freyi e suas relações ecológicas no Reservatório de Itupararanga - Votorantim/SP." Universidade Federal de São Carlos, 2014. https://repositorio.ufscar.br/handle/ufscar/8363.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Preliminary studies on reservoir Itupararanga indicate that the seasonal dynamics of plankton community is not being strongly controlled by bottom-up forces. Cianobactéria Cylindrospermopsis raciborskii and clorofícea Monoraphidium contortum are the dominant phytoplankton species in this reservoir. Bosmina freyi, recently described, is the dominant zooplankton in Itupararanga and there is no records of studies feeding habits of this specie. Therefore, the present study aims to assess the importance of the cladoceran Bosmina freyi as consumers of phytoplankton species: Monoraphidium contortum and Cylindrospermopsis raciborkii to better understand the ecological role of this organism in the planktonic food web in reservoir Itupararanga. M. contortum and three types of strain C.raciborskii, toxic strain (Cy.tox), strain with large filaments (Cy.grd) and strain with small filaments (Cy.peq) where ofered for Bosmina freyi. For each treatment, were calculated the density, cell volume, biovolume before and after incubation with B. freyi.Also calculated the ingestion and filtration rates. Qualitative models have also been made to describe and make predictions on the plankton community Itupararanga when there are changes in the population of Chaoborus sp. It was noted that B. freyi is able to efficiently ingest C.raciborskii including toxic strain, but presented difficulties in filter and ingest filaments of Cy.grd.Besides, B.freyi seems to be able to cut up filaments of C.raciborskii for ingestion. No food preference was observed by M.contortum. Qualitative models made in this study corroborate the hypothesis that seasonal variations in plankton reservoir Itupararanga may be being controlled by top-down forces due the presence of Chaoborus sp.
Estudos preliminares no Reservatório de Itupararanga indicam que a dinâmica sazonal da comunidade planctônica não está sendo fortemente controlada por forças botton-up. A cianobactéria Cylindrospermospisi raciborskii e a clorofícea Monoraphidium contortum são as espécies fitoplanctônicas dominantes neste reservatório. Bosmina freyi, espécie descrita recentemente, é a dominante do zooplâncton em Itupararanga e não há registros de estudos sobre os hábitos alimentares desta espécie. Devido a isso o presente trabalho pretende avaliar a importância do cladócero Bosmina freyi como consumidor das espécies fitoplanctônicas: Monoraphidium contortum e Cylindrospermopsis raciborkii para melhor entender o papel ecológico deste organismo na teia alimentar planctônica no reservatório de Itupararanga. Foram oferecidos M. contortum e três tipos de cepa C.raciborskii, cepa tóxica (Cy.tox), cepa com filamentos grandes (Cy.grd) e cepa com filamentos pequenos (Cy.peq) para Bosmina freyi. Para cada tratamento, calcularam-se as densidades, volumes celulares, biovolumes antes e depois do período de incubação com B. freyi, além disso, foram calculadas as taxas de filtração e ingestão. Foram feitos também modelos qualitativos para descrever e fazer previsões na comunidade planctônica do reservatório de Itupararanga quando há alterações na população de Chaoborus sp.Observou-se que B. freyi é capaz de ingerir eficientemente C.raciborskii inclusive a cepa tóxica, porém apresentou dificuldades em filtrar e ingerir filamentos de Cy.grd. Além disso, B.freyi parece ser capaz de cortar filamentos de C.raciborskii para ingestão. Não foi observado preferência alimentar por M.contortum. Os modelos qualitativos feitos neste estudo corroboram com a hipótese de que as variações sazonais do plâncton no reservatório de Itupararanga podem estar sendo controladas por forças top-down pela presença de Chaoborus sp.
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7

Pelegrini, Nubia Natalia de Brito. "Sistema de filtração lenta no tratamento de percolado do aterro sanitario de Limeira-SP." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257157.

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Анотація:
Orientador: Jose Euclides Stipp Paterniani
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola
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Resumo: A disposição final de resíduos sólidos é uma prática que ainda traz sérios impactos ao meio ambiente. Nos aterros sanitários, os resíduos passam por processos físicos, químicos e biológicos de decomposição, gerando uma fração gasosa (composta principalmente por gases dióxido de carbono e metano) e uma fase líquida conhecida como chorume (ou percolado de aterro sanitário). O chorume de lixo é um líquido com elevado potencial poluente, os métodos convencionais utilizados em seu tratamento têm descartado-o com intensa coloração e alta toxicidade. Este trabalho teve como objetivo implantar em escala piloto um sistema de filtração lenta precedido de uma pré-filtração, apenas em manta sintética não tecida, para o tratamento de chorume de lixo ¿in natura¿, proveniente do aterro sanitário da cidade de Limeira-SP. O filtro lento foi constituído por um tanque cilíndrico de plástico tendo como meio filtrante areia e mantas sintéticas não tecidas. A taxa de filtração adotada durante os experimentos foi de 3 m3/m2.dia. O sistema de tratamento em estudo apresentou reduções consideráveis dos valores de alguns parâmetros de controle ambiental indicando a possibilidade do uso da filtração lenta para remediação de águas residuárias. As principais reduções obtidas referem-se a 40% de turbidez, 21% da coloração, 35% de dureza, 35% de carbono orgânico total (TOC) e reduções consideráveis de metais pesados (60% de cádmio, 30% de chumbo, 25% de cobre e 30% de cromo). Com relação à reutilização do chorume tratado em atividades agrícolas ainda são necessárias maiores reduções dos valores de parâmetros analíticos através da complementação com outras tecnologias de tratamento
Abstract: The final disposition of solids residues is a practice that still brings serious impacts to the environment. In sanitary landfill, the residues goes through physical, chemical and biological decomposition processes, generating into a gas phase (mainly composed by CH4 and CO2) and a liquid phase known as leachate. The waste leachate is a liquid with high pollutant potential. The conventional methods used in the treatment this residue have discarded him with intense coloration and high toxicity. This work had as objective implant in pilot scale a system of slow sand filtration preceded of a pré-filtration, only in non-woven synthetic fabrics, for the waste leachate treatment in natura, originating from the sanitary landfill of the city of Limeira-SP. The slow sand filter is constituted by a plastic cylindrical tank, sands and non-woven synthetic fabrics. The filtration rate adopted during the experiments it was of 3 m3/m2.dia. The treatment system in study presented considerable reductions of some values of environmental parameters control indicating the possibility of the use of the slow filtration for remediação of wastewaters. The main obtained reductions were 40% of turbidity, 21% of color, 35% of hardness, 35% of total organic carbon (TOC) and reductions considerably of heavy metals (60% of cadmium, 30% of lead, 25% of cupper and 30% of chrome). For the reuse of the treated leachate in agricultural activities are necessary larger reductions of some values of analytic parameters through the complementation with other treatment technologies. eywords: Landfill Leachate, Sanitary Landfill, Slow Sand Filtration, Reuse
Mestrado
Agua e Solo
Mestre em Engenharia Agrícola
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8

Pinto, Diego de Oliveira 1987. "Aplicabilidade do método 1623 e do método de filtração em membranas para detecção de cistos de Giardia spp. e oocistos de Cryptosporidium spp. em amostras hídricas considerando diferentes faixas de turbidez, e estudo da etapa de purificação por separação imunomagnética : Applicability of method 1623 and membrane filtration method for detection of Giardia spp. cysts and Cryptosporidium spp. oocysts in water samples considering different levels of turbidity, and study of immunomagnetic separation phase." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315680.

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Анотація:
Orientador: Romeu Cantusio Neto
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Os protozoários patogênicos Giardia spp. e Cryptosporidium spp. estão entre os principais contaminantes associados à veiculação hídrica e seu monitoramento em águas de abastecimento público é determinado pela Portaria n. 2.914/2011, do Ministério da Saúde do Brasil. Este trabalho foi dividido em duas partes. Na primeira, foi realizado um estudo da aplicabilidade do Método 1623 utilizando Filta-Max® (FMx) e Método de Filtração em Membranas (FM). Cistos de Giardia spp. e oocistos de Cryptosporidium spp. foram inoculados artificialmente em amostras de água bruta superficial proveniente do rio Atibaia, coletadas na cidade de Campinas/SP, Brasil, e agrupadas de acordo com faixas de turbidez. Cistos de Giardia spp. naturalmente presentes nas amostras foram detectados em todas as faixas de turbidez por ambos os métodos. O método de FM atendeu aos critérios de controle de qualidade analítica da USEPA em todas as faixas de turbidez. Não houve diferença estatística significativa entre os métodos de FMx e FM. Na segunda parte deste trabalho, foi feito um estudo da etapa de purificação por Separação Imunomagnética (IMS) no qual foi avaliado o desempenho dos procedimentos de dissociação: ácida e térmica; bem como investigado possíveis causas de perdas dos organismos-alvo durante execução desta etapa. A dissociação ácida apresentou maior média de eficiência de recuperação e precisão do que a dissociação térmica para cistos de Giardia spp.. Para oocistos de Cryptosporidium spp. não houve diferença estatística significativa. Após o procedimento de dissociação, tanto ácida quanto térmica, haviam cistos e oocistos aderidos às beads (micro-esferas magnéticas) que seriam descartadas de acordo com o protocolo padrão da IMS
Abstract: The pathogenic protozoa Giardia spp. and Cryptosporidium spp. are some the major waterborne contaminants and their monitoring in water supply is determined in Decree no. 2.914/2011, the Brazil¿s Ministry of Health. This study was divided in two parts. In the first, a study was conducted to evaluate the applicability of two methods for concentration of pathogenic protozoa Giardia spp. and Cryptosporidium spp. in water samples: Method 1623 using Filta-Max® (FMX) and Membrane Filtration (MF) Method. Giardia spp cysts and Cryptosporidium spp oocysts were artificially inoculated in samples of raw surface water from the Atibaia River, collected in Campinas/SP, Brazil, and grouped according to ranges of turbidity. Giardia spp. cysts naturally present in the samples were detected in all ranges of turbidity by both methods. The method of FM met the criteria for analytical quality control of USEPA in all ranges of turbidity. There was no statistically significant difference between the methods of FM and FMX. In the second part of this work, a study was made of the purification step by immunomagnetic separation (IMS) in which was evaluate the performance of the dissociation procedures: acid and heat, as well as investigating possible causes loss of target organisms during execution of this step. The acid dissociation showed higher mean recovery efficiency and accuracy than heat dissociation for Giardia spp.. For Cryptosporidium spp. difference was not statistically significant. After the dissociation procedure, both acid and heat, cysts and oocysts were still adhered to the beads (magnetic microspheres) that would be discarded, according to the standard protocol of IMS
Mestrado
Relações Antrópicas, Meio Ambiente e Parasitologia
Mestre em Biologia Animal
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9

Mthombeni, Nomcebo Happiness. "Experimental investigation and modelling of oligodynamic nanoparticles based filtration system for water disinfection." 2011. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000251.

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M. Tech. Engineering Chemical.
Developes and evaluate next generation antimicrobial filtration systems based on oligodynamic nanoparticles for complimentary water disinfection systems (CDWS) in under developed regions
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10

"Recycling Water and Nutrients When Producing the Cyanobacterium Synechocystis sp. PCC 6803." Master's thesis, 2015. http://hdl.handle.net/2286/R.I.29824.

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abstract: Large-scale cultivation of photosynthetic microorganisms for the production of biodiesel and other valuable commodities must be made more efficient. Recycling the water and nutrients acquired from biomass harvesting promotes a more sustainable and economically viable enterprise. This study reports on growing the cyanobacterium Synechocystis sp. PCC 6803 using permeate obtained from concentrating the biomass by cross-flow membrane filtration. I used a kinetic model based on the available light intensity (LI) to predict biomass productivity and evaluate overall performance. During the initial phase of the study, I integrated a membrane filter with a bench-top photobioreactor (PBR) and created a continuously operating system. Recycling permeate reduced the amount of fresh medium delivered to the PBR by 45%. Biomass production rates as high as 400 mg-DW/L/d (9.2 g-DW/m2/d) were sustained under constant lighting over a 12-day period. In the next phase, I operated the system as a sequencing batch reactor (SBR), which improved control over nutrient delivery and increased the concentration factor of filtered biomass (from 1.8 to 6.8). I developed unique system parameters to compute the amount of recycled permeate in the reactor and the actual hydraulic retention time during SBR operation. The amount of medium delivered to the system was reduced by up to 80%, and growth rates were consistent at variable amounts of repeatedly recycled permeate. The light-based model accurately predicted growth when biofilm was not present. Coupled with mass ratios for PCC 6803, these predictions facilitated efficient delivery of nitrogen and phosphorus. Daily biomass production rates and specific growth rates equal to 360 mg-DW/L/d (8.3 g/m2/d) and 1.0 d-1, respectively, were consistently achieved at a relatively low incident LI (180 µE/m2/s). Higher productivities (up to 550 mg-DW/L/d) occurred under increased LI (725 µE/m2/s), although the onset of biofilm impeded modeled performance. Permeate did not cause any gradual growth inhibition. Repeated results showed cultures rapidly entered a stressed state, which was followed by widespread cell lysis. This phenomenon occurred independently of permeate recycling and was not caused by nutrient starvation. It may best be explained by negative allelopathic effects or viral infection as a result of mixed culture conditions.
Dissertation/Thesis
Masters Thesis Civil and Environmental Engineering 2015
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Тези доповідей конференцій з теми "Sp-filtration"

1

Shevnin, V. "Distinction of SP Anomalies Between Filtration and Diffusion-Adsorption Origin." In 25th European Meeting of Environmental and Engineering Geophysics. European Association of Geoscientists & Engineers, 2019. http://dx.doi.org/10.3997/2214-4609.201903469.

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2

Shevnin, V. A. "Identification of Sp Anomalies' Nature to Distinguish Between Filtration and Diffusion-Adsorption Origin of Sp Anomalies." In Engineering and Mining Geophysics 2019 15th Conference and Exhibition. European Association of Geoscientists & Engineers, 2019. http://dx.doi.org/10.3997/2214-4609.201901683.

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3

Bondar, Mikhail, Andrey Osipov, Andrey Groman, Igor Koltsov, Georgy Shcherbakov, and Sergey Milchakov. "Evaluating Efficiency of Surfactant-Polymer Flooding with Single Well Chemical Tracer Tests at Kholmogorskoye Field." In Abu Dhabi International Petroleum Exhibition & Conference. SPE, 2021. http://dx.doi.org/10.2118/207314-ms.

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Abstract EOR technologies in general and surfactant-polymer flooding (SP) in particular is considered as a tertiary method for redevelopment of mature oil fields in Western Siberia, with potential to increase oil recovery to 60-70% OOIP. The selection of effective surfactant blend and a polymer for SP flooding a complex and multi-stage process. The selected SP compositions were tested at Kholmogorskoye oilfield in September-December 2020. Two single well tests with partitioning chemical tracers (SWCTT) and the injectivity test were performed. The surfactant and the polymer for chemical EOR were selecting during laboratory studies. Thermal stability, phase behavior, interfacial tension and rheology of SP formulation were investigated, then a prospective chemical design was developed. Filtration experiments were carried out for optimization of slugs and concentrations. Then SWCTT was used to evaluated residual oil saturation after water flooding and after implementation of chemical EOR in the near wellbore areas. The difference between the obtained values is a measure of the efficiency of surfactant-polymer flooding. Pandemic restriction shifted SWCTT to the period when temperature dropped below zero and suitable for winter conditions equipment was required. Two SWCTT were conducted with same surfactant, but different design of slugs in order to prove technical and economic models of SP-flooding. Long-term polymer injectivity was accessed at the third well. Oil saturation of sandstone reservoir after the injection of a surfactant-polymer solution was reduced about 10% points which is around one third of the residual oil after water flooding. Results were compared with other available data such as well logging, lab core flooding experiments, and hydrodynamic simulation. Modeling of SWCTT is ongoing, current interpretation confirms the increase the oil recovery factor after SP-flooding up to 20-25%, which is a promising result. Temperature model of the bottom hole zone was created and verified. The model predicts that temperature of those zones essentially below that average in the reservoir, which is important for interpretation of tracer test and surfactant efficiency. The tested surfactant showed an acceptable efficiency at under-optimum conditions, which is favorable for application of the SP formulation for neighboring field and layers with different reservoir temperatures, but similar water composition. In general, the results of the conducted field tests correlate with the results of the core experiments for the selected surfactant
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4

Almorihil, Jawaher, Ahmed Alsmaeil, Ziyad Kaidar, and Abdulkareem AlSofi. "Produced Water Quality: Uncovering the Effects of Centrifugation for Water and Chemical Floods Using a Dispersion Analyzer." In SPE/IATMI Asia Pacific Oil & Gas Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/205534-ms.

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Abstract A second stage of gravity settling with the addition of demulsifiers or clarifiers is commonly used in processing plants to further treat the separated produced water. In previous work, we demonstrated gravity settling lower efficiency in removing oil carryover from produced water compared to other processing techniques. Both centrifugation and filtration were found to significantly improve the separated water quality. In this work, we focus on centrifugation and further evaluate its efficiency in improving the quality of separated water for both water and chemical floods, specifically surfactant/polymer (SP) flooding. Samples were firstly prepared to imitate the separation plant projected feed and operations. Synthetic representative brines were prepared and used with dead crude oil to prepare the oil/water emulsions. Emulsion separation was conducted at different temperatures, as well as different concentrations of SP, and the demulsifier. The kinetics and efficiency of separation were thoroughly studied over two stages of separation: primary gravity settling and secondary centrifugation. We performed gravitational separation using bottle tests in order to firstly obtain the separated produced water for use in secondary water treatment studies and to secondly further investigate gravity settling kinetics and efficiency. Water quality, in terms of oil content, was then assessed through solvent extraction and UV analyses. Samples of the produced water separated by the primary gravity settling were then exposed to secondary centrifugation. Centrifugation was performed at different rotational speeds using a dispersion analyzer. Light transmission evolution in space and time was used to study kinetics, efficiency and mechanisms of secondary centrifugation. The results reconfirmed that a single-stage gravity settling is not sufficient to reduce oil carryover to acceptable levels for disposal and re-injection into oilfields. Secondary centrifugation yielded clear and significant improvement in water quality even in the presence of EOR chemicals. With centrifugation, the separation efficiency was a function of the rotational speed. Higher rotational speeds resulted in higher creaming velocities and faster separation. In addition, creaming velocities indicated that higher temperatures yield favorable effects on oil droplets migration and separation rates. This is possibly due to the lower density and larger bouncy at higher temperatures. Based on these results, we conclude that secondary centrifugation is very efficient and effective in improving the quality of separated water. In terms of the effects of investigated EOR formulations, SP addition caused minor but manageable reduction in separated water quality at a level that would not harm conventional disposal practices.
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Aiswarya, K., A. A. Alfiya, R. Deepak, V. S. Devadath, and K. P. Ramaswamy. "Development of Alkali Activated Pervious Cementless Concrete." In International Web Conference in Civil Engineering for a Sustainable Planet. AIJR Publisher, 2021. http://dx.doi.org/10.21467/proceedings.112.54.

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Pervious concrete is a topic of recent interest and finds vivid applications such as for discharging rain water, filtration of waste water etc. Pervious concrete made with cement as a binder poses serious threats to the environment due to the large amount of green house gases released, especially carbon dioxide, owing to the production of cement. Therefore, it is imperative to find a suitable substitute for cement in the production of concrete. This study presents about the production of pervious concrete, completely replacing cement with fly ash geopolymer binder system. Pervious geopolymer concretes were prepared from Class F fly ash, sodium silicate, sodium hydroxide solution, coarse aggregate and a little quantity of fine aggregate. The alkali to binder ratio of 0.50 by mass and sodium silicate to sodium hydroxide ratio of 2.50 were used. In order to improve the workability of mixture, a super plasticizer Conplast SP 430 (2-3% by weight of binder) was added. Temperature curing at 50 ºC for 24 hours was done. Compression, permeability and water absorption tests were conducted on the specimen at 7 days. The compressive strength of the mixture was found to be 11.66 MPa which is more than that of a brick and water absorption was nearly 2%. The permeability of water through the specimen was found to be 24.63 ml/sec for a pervious cubical specimen of size 10 cm. The pervious concretes produced in this work were not only environment friendly but also achieved better mechanical properties and water permeability. It is inferred that the fly ash geopolymer system could be used to produce pervious concrete.
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6

"Ion Filtration Effect of Superabsorbent Polymers for Internal Curing." In SP-289: Twelfth International Conference on Recent Advances in Concrete Technology and Sustainability Issues (Hard Copy). American Concrete Institute, 2012. http://dx.doi.org/10.14359/51684278.

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