Relevant bibliographies by topics / Sulphate released

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  2. Dissertations / Theses
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Academic literature on the topic 'Sulphate released'

Author: Grafiati
Published: 4 June 2021
Last updated: 8 February 2022

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Journal articles on the topic "Sulphate released"

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Ahuja, K. K., and D. J. Gilburt. "Involvement of sperm sulphatases in early sperm-zona interactions in the hamster." Journal of Cell Science 78, no. 1 (1985): 247–61. http://dx.doi.org/10.1242/jcs.78.1.247.

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Sulphatase preparations from Abalone entrails, the limpet Patella vulgata and ox liver, as well as artificial substrates for these enzymes, were used in the hamster in vitro fertilization system to study the possible roles of sperm sulphatases in sperm-zona pellucida interactions. p-nitrophenyl sulphate, p-nitrocatechol sulphate, ascorbate 2-sulphate, as well as D-glucopyranose and D-galactopyranose, both sulphated at the 3, 4 or 6 position but not the 2 position, inhibited fertilization in a dose-dependent manner. Sperm-egg fusion was not inhibited by the substrates used and eggs pre-treated with sulphates could readily be fertilized. Sperm motility and therefore viability was unaffected by inhibitory concentrations of substrates as determined by rhodamine 123 labelling of motile spermatozoa. Acrosomal integrity of rhodamine-labelled spermatozoa was assessed and found to be unaffected by inhibitory levels of substrates. Fertilization was inhibited by high concentrations of the two molluscan sulphatases but not by purified ox liver sulphatase. Pre-treatment of eggs with these enzymes did not prevent fertilization. Long-term exposure of hamster oocytes to N-acetylhexosaminidase or limpet sulphatase caused thinning and distension of the zona pellucida but these changes were not observed with the ox liver sulphatase. The results suggest that a glycosulphatase is probably released from hamster spermatozoa during sperm-egg adhesion and, or, penetration. If sperm-egg adhesion molecules are sulphated, the commercially available sulphatases would be unsuitable for their characterization.
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Han, J. R., and M. C. Liu. "Polarized secretion of tyrosine-sulphated proteins and free tyrosine O-sulphate by filter-grown Madin-Darby canine kidney (MDCK) cells." Biochemical Journal 279, no. 1 (1991): 289–95. http://dx.doi.org/10.1042/bj2790289.

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Filter-grown Madin-Darby canine kidney (MDCK) cells labelled for 24 h with [35S]sulphate were found to secrete macromolecules [35S]sulphated on their carbohydrate moieties predominantly into the basolateral medium, whereas the tyrosine-[35S]sulphated proteins synthesized were predominantly secreted into the apical medium. In contrast with the predominant apical secretin of tyrosine-[35S]sulphated proteins, the free tyrosine O-[35S]sulphate (Tyr[35S]) was released mostly into the basolateral medium. A time-lapse study using prelabelled MDCK cells incubated in fresh medium revealed that, during the 48 h time course monitored, the release of tyrosine-[35S]sulphated proteins into the apical medium was faster and quantitatively greater than that into the basolateral medium. During the same time there was a concomitant release, predominantly into the basolateral medium, of the free Tyr[35S] derived from the degradation of tyrosine-[35S]sulphated proteins. An endocytotic degradation experiment was performed to demonstrate the endocytosis of tyrosine-sulphated proteins and their degradation to generate free TyrS. It was found that free Tyr[35S] was generated and released when an apically secreted (or basolaterally secreted) tyrosine-[35S]sulphated protein preparation was added to the apical medium (or the basolateral medium) of unlabelled filter-grown MDCK cells. In both cases, the free Tyr[35S] generated was predominantly released into the basolateral medium similar to the results obtained in the time-lapse study.
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Liu, M. C., M. Suiko, and F. Lipmann. "Rapid catabolism of tyrosine-O-sulphated proteins and the formation of free tyrosine O-sulphate as an end product in rat embryo fibroblasts." Biochemical Journal 243, no. 2 (1987): 555–59. http://dx.doi.org/10.1042/bj2430555.

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Rat embryo fibroblasts, line 3Y1, were prelabelled for 24 h with [35S]sulphate and incubated in fresh medium without [35S]sulphate. A rapid efflux of the overall 35S-labelled compounds from the cells into the medium was observed. After 9 h of incubation, about 50% of the total 35S radioactivity appeared in the medium and up to 84.3% did so at the end of a 48 h incubation. Determination of [35S]sulphated macromolecules present in both the cell-associated and the incubation-medium fractions at different time points during incubation indicated that the majority of the 35S-labelled compounds released from the cells were low-Mr products derived from digestion of the [35S]sulphated macromolecules. Further analysis for tyrosine-O-[35S]sulphated proteins, which constituted only a small fraction of the overall [35S]sulphated macromolecules, showed that, after 9 h of incubation, there was a 65% decrease in the cell-associated fraction, and only 16.4% remained after 48 h. During that time, an amount equivalent to 20.7% of the cell-associated tyrosine-O-[35S]sulphated proteins originally present was released into the medium. Free tyrosine O-[35S]sulphate was generated in the cells and excreted into the incubation medium. Its rate of increase with time, however, was slow, and could account for only 12.4% of the tyrosine-O-[35S]sulphated proteins catabolized at the end of the 48 h incubation.
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Whiteley, C. G., X. Melamane, B. Pletschke, and P. D. Rose. "The enzymology of sludge solubilisation utilising sulphate reducing systems: the role of lipases." Water Science and Technology 48, no. 8 (2003): 159–67. http://dx.doi.org/10.2166/wst.2003.0465.

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The first stage in the degradation and recycling of particulate organic matter is the solubilisation and enhanced hydrolysis of complex polymeric organic carbon structures associated with the sulphidogenic environment. An investigation into the enzymology of these processes has shown that lipase enzyme activities were found predominantly associated with the organic particulate matter of the sewage sludge. Sonication of the sludge gave an increase in enzyme activity as the enzymes were released into the supernatant. pH and temperature optimisation studies showed optima at between 6.5 and 8 and 50-60°C, respectively. All the lipase enzymes from the methanogenic bioreactors indicated extensive stability for at least an hour at their respective optimum temperatures and pH; sulphidogenic lipases reflected limited stability at these temperatures and pH during this time period. Though sulphate showed inhibitory properties towards lipases both sulphide and sulphite appeared to enhance the activity of the enzymes. It is argued that these sulphur species, liberated at different times during the sulphate reduction process, disrupt the integrity of the organic particulate floc by neutralising acidic components on the surface. The release of further entrapped enzymes from the organic particulate matter results in a subsequent enhancement of hydrolysis of polymeric material.
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Cortés-Hernández, Dora A., Luis A. Bretado-Aragón, W. Ortega-Lara, David Rentería-Zamarrón, and Y. Salinas-Delgado. "Gentamicin Sulphate Release from Bioactive Ceramic Calcium Silicates." Key Engineering Materials 396-398 (October 2008): 527–30. http://dx.doi.org/10.4028/www.scientific.net/kem.396-398.527.

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Gentamicin sulphate was mixed with two different sol-gel derived calcium silicates (akermanite or wollastonite). Each of the mixtures was isostatically pressed. Samples were immersed in simulated body fluid for 21 days. The presence of the antibiotic showed no effect on the in vitro bioactivity of the ceramics. For evaluating the gentamicin sulphate release, samples were immersed in a phosphate buffered saline solution for different periods of time. Most of the gentamicin sulphate was released during the first 7 days. However, akermanite showed a lower antibiotic release rate than that observed for wollastonite.
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Lindblom, A., G. Bengtsson-Olivecrona, and L. A. Fransson. "Domain structure of endothelial heparan sulphate." Biochemical Journal 279, no. 3 (1991): 821–29. http://dx.doi.org/10.1042/bj2790821.

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The domain structure of heparan sulphate chains from an endothelial low-density proteoglycan was examined using specific degradations of the chains while attached to the intact proteoglycan. ‘Inner’ chain fragments, remaining on the protein core, were separated from ‘outer’ fragments by gel chromatography, and were subsequently released from the protein core by alkaline cleavage. The structure of ‘inner’ and ‘outer’ chain fragments was then examined and compared. Using deaminative cleavage we obtained evidence that the first N-sulphated glucosamine residue is variably positioned some 10-17 disaccharides from the xylose-serine linkage of the proteoglycan. Digestion with heparinase yielded ‘inner’ and ‘outer’ fragments covering a broad range of different sizes, indicating a scarce and variable distribution of sulphated iduronic acid in the native chains. N-sulphated glucosamine occurred more frequently in the ‘outer’ fragments. We also studied the affinity of the endothelial heparan sulphate chains towards two presumptive biological ligands, namely antithrombin III and lipoprotein lipase. A major part of the endothelial heparan sulphate chains showed a weak affinity for antithrombin III and the affinity was essentially lost on heparinase digestion. On lipoprotein lipase-agarose the endothelial heparan sulphate chains were eluted at the same salt concentration as heparin, and the binding persisted, although with decreased strength, after digestion with heparinase.
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Jacobsen, Tomas, Bo Jensen, Jørgen Olsen, and Knud Allermann. "Preparation of protoplasts from mycelium and arthroconidia of Geotrichum candidum." Canadian Journal of Microbiology 31, no. 2 (1985): 93–96. http://dx.doi.org/10.1139/m85-019.

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Protoplasts were released from mycelium and the cylindrical type of arthroconidia from Geotrichum candidum by a lytic enzyme (Novozym 234). This enzyme was unable to release protoplasts from the ellipsoidal type of arthroconidia, which reflects a difference in the cell walls of the two types of conidia. The conditions necessary to obtain stable protoplasts were determined. Magnesium sulphate (0.8 M) was the best osmotic stabilizer for the formation of protoplasts, whereas both mannitol and magnesium sulphate could be used for regeneration. The regeneration was faster with mannitol than with magnesium sulphate.
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Hewitt, C. Nicholas, and Brian Davison. "Field measurements of dimethyl sulphide and its oxidation products in the atmosphere." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 352, no. 1350 (1997): 183–89. http://dx.doi.org/10.1098/rstb.1997.0013.

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Dimethyl sulphide (DMS) is released into ocean waters by phytoplankton and may then cross the water–air interface into the atmosphere. Various models have been formulated to describe its behaviour in the atmosphere. Here, measurements of its concentrations and those of its major oxidation products, methane sulphonate, sulphur dioxide, non sea–salt sulphate and demethyl sulphoxide, in both the gas and aerosol phases, in Atlandtic air, are used to validate these qualitative descriptions of its oxidation. Behaviour consistent with day–time oxidation by the hydroxyl radical, with the yield of methane sulphonic acid being both temperature dependent and under the influence of the nitrogen dioxide mixing ratio, is seen. The rapid production of new particles also seems likely under certain conditions but it is not clear whether or not they enhance the concentrations of cloud condensation nuclei in the maritime troposphere. In maritime air a substantial fraction of the sulphate formed appears to be neutralized by reaction with ammonia to form ammonium aerosol.
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Krusius, T., V. N. Reinhold, R. K. Margolis, and R. U. Margolis. "Structural studies on sialylated and sulphated O-glycosidic mannose-linked oligosaccharides in the chondroitin sulphate proteoglycan of brain." Biochemical Journal 245, no. 1 (1987): 229–34. http://dx.doi.org/10.1042/bj2450229.

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We have previously described the structures of neutral and sialylated O-glycosidic mannose-linked tetrasaccharides and keratan sulphate polysaccharide chains in the chondroitin sulphate proteoglycan of brain. The present paper provides information on a series of related sialylated and/or sulphated tri- to penta-saccharides released by alkaline-borohydride treatment of the proteoglycan glycopeptides. The oligosaccharides were fractionated by ion-exchange chromatography and gel filtration, and their structural properties were studied by methylation analysis and fast-atom-bombardment mass spectrometry. Five fractions containing [35S]sulphate-labelled oligosaccharides were obtained by ion-exchange chromatography, each of which was eluted from Sephadex G-50 as two well-separated peaks. The apparent Mr values of both the large- and small-molecular-size fractions increased with increasing acidity (and sulphate labelling) of the oligosaccharides. The larger-molecular-size fractions contained short mannose-linked keratan sulphate chains of Mr 3000-4500, together with some asparagine-linked oligosaccharides. The smaller tri- to penta-saccharides, of Mr 800-1400, appear to have a common GlcNac(beta 1-3)Manol core, and to contain one to two residues of sialic acid and/or sulphate.
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Okayama, M., K. Oguri, Y. Fujiwara, et al. "Purification and characterization of human platelet proteoglycan." Biochemical Journal 233, no. 1 (1986): 73–81. http://dx.doi.org/10.1042/bj2330073.

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Freshly prepared platelets were shown to contain glycosaminoglycans equivalent to 530 micrograms of hexuronate/10(11) platelets. When the platelets were extracted with 4 M-guanidinium chloride containing proteinase inhibitors, and the extract was dialysed extensively against 7 M-urea solution, almost all of proteoglycan was recovered in the urea-soluble fraction. The proteoglycan was purified from the urea-soluble fraction with a yield of 47% by DEAE-Sephacel chromatography, CsCl-density-gradient centrifugation, Bio-Gel A-15m gel filtration and then rechromatography on DEAE-Sephacel. The purified proteoglycan contained 30% glucuronic acid, 32% N-acetylgalactosamine, 14% sulphate and 15% protein. Serine, glutamic acid, glycine, aspartic acid and leucine accounted for 64% of the total amino acids. The Mr of the proteoglycan was assessed to be approx. 136000 by sedimentation-equilibrium methods. The galactosaminoglycan released by alkaline-borohydride treatment of the proteoglycan was converted stoichiometrically into 4-sulphated unsaturated disaccharide by digestion with chondroitinase AC-II, indicating that the galactosaminoglycan was fully sulphated chondroitin 4-sulphate. The apparent Mr of the chondroitin sulphate was assessed to be 28000 by gel filtration on Bio-Gel A-0.5m (KD 0.18). On two-dimensional electrophoresis on a cellulose acetate membrane, the chondroitin sulphate gave a single compact spot co-migrating with a reference chondroitin sulphate, indicating that the chondroitin sulphate chains were homogeneous in both length and charge density. On the basis of these results, the proteoglycan in human platelets was concluded to be a macromolecule of Mr 136000 containing four chondroitin 4-sulphate chains each with the apparent Mr of 28000.
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Dissertations / Theses on the topic "Sulphate released"

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Colas, Jérémy. "Étude de la valorisation des déblais de chantiers de tunnels en granulats à béton." Phd thesis, Université Paris-Est, 2012. http://tel.archives-ouvertes.fr/tel-00806513.

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La société LTF (Lyon Turin Ferroviaire), filiale de RFF (Réseau Ferré de France) et de RFI (Réseau Ferré Italien) est le promoteur de la section transfrontalière de la future liaison ferroviaire entre Lyon et Turin. LTF souhaite valoriser une grande partie des 16 millions de m3 de déblais qui seront générés par les chantiers du futur tunnel de base en granulats à béton pour le revêtement du tunnel. Cette solution est proposée dans le cadre d'une démarche de développement durable. Cependant, pour une partie des matériaux qui doivent être valorisés en granulats à béton, la teneur en sulfates est comprise entre 1,61 et 4,30% en masse (exprimé en SO3). Ces matériaux se démarquent alors par rapport au contexte réglementaire qui limite la teneur en sulfates dans les granulats à béton à 0,2% pour ce type d'ouvrage. Cette prescription est appliquée pour éviter les risques de dégradation du béton par réaction des sulfates apportés par les granulats avec certains composants présents dans le ciment. Ce phénomène est connu sous le terme de réaction sulfatique interne. Les travaux de recherche ont porté dans un premier temps sur la lixiviation des sulfates issus des matériaux d'excavation. Les résultats ont montré que les sulfates sont rapidement accessibles dans les fractions granulométriques inférieures à 4 mm. Un possible traitement des matériaux par lavage avant leur utilisation dans le béton peut être une solution pour limiter l'attaque sulfatique interne. Dans un second temps, pour définir un liant adapté à ce type de granulats, une étude comparative de différents ciments supposés résistants aux sulfates a été mise en place. Trois essais accélérés ont été développés afin de prendre en compte le risque de dégradation des matériaux cimentaires par formation d'ettringite et de thaumasite. Seuls deux ciments présentent un bon comportement vis-à-vis de la réaction sulfatique interne engendrée par des granulats contenant une forte teneur en sulfates. Il s'agit d'un ciment Portland à très faibles teneur en alcalins et ne contenant quasiment pas d'aluminates tricalciques ainsi qu'un ciment sursulfaté. Enfin, une dernière solution innovante a été proposée et réside dans l'utilisation des sulfates apportés par les matériaux d'excavation pour réaliser le gypsage du ciment. Les sulfates provenant du sable excavé permettent de réguler correctement la prise du matériau cimentaire au même titre que les sulfates de calcium ajoutés au clinker dans le ciment
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Harper, Frank D. "Sulfur release during the pyrolysis of kraft black liquor." Diss., Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/5581.

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Bakke, Bruce W. "Reduction of sulfur release through indigester oxidation in kraft pulping." Thesis, Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/11691.

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Sandvik, Marianne. "Evaluation and characterization of calcium sulphate microneedles for rapid drug release." Thesis, Umeå universitet, Kemiska institutionen, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-101888.

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Karlsson, Lovisa. "Release of elements from unprocessed- and processed shale from Kvarntorp : Effect from different pH." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-28628.

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The alum shale of Sweden is a sulphidic black shale which was mined for its contents of alum during the 17th-19th centuries. During the thirst half of the 20th century alum shale from Kvarntorp was pyrolysed for refinement of its organic matter. The refuse from the pyrolysis process were deposited in a deposit area which is today known as Kvarntorpshögen. This deposit is still hot due to on-going oxidation of the organic matter, pyrite oxidation and the neutralisation of acid by limestone. This heat generation prevents percolation of water to any greater extent due to evaporation. Once it cools the deposit will be susceptible to extraction. Three materials from the Kvarntorp deposit and a block of alum shale were sampled from the Kvarntorp area. These four materials were crushed, sieved and extracted. The extraction experiment was performed at controlled pH which corresponded to dissolution equilibrium of pyrite, carbon dioxide/oxygen, calcite and slaked lime. In the fifth extraction series the material was allowed to set the pH of the water phase. The extraction procedure lasted for 26 days. Metal content of the four shale materials were analysed by XRF (including contents of sulphur, phosphorous and chloride) and by digestion followed by ICP-MS analysis. Mineralogy of the four materials and the extraction residues were studied by XRD analysis. Metal concentrations of the aqueous samples were analysed by ICP-MS and concentrations of dissolved organic- and inorganic carbon by TOC. Electrical conductivity and concentrations of sulphate was also analysed in aqueous phases with non-manipulated pH. Sulphate and calcium concentrations were highest in aqueous samples from weathered fines indicating the presence of gypsum. Presence of gypsum was also confirmed by XRD. Gypsum indicates weathering since it is a neutralisation product of calcite and the sulphuric acid generated by pyrite oxidation. Concentrations of dissolved organic carbon in samples with pH 12.5 were found to be highest from red processed shale and lowest from samples of shale. This indicates different hydrolysis properties or origin of the organic matter in the materials. The majority of analysed metals had highest solid solution distribution under acidic, i.e. pH 3.0, conditions. Under these conditions it was samples from the relatively non-weathered shale that had the highest release of metals, with a few exceptions. At pH 12.5 high concentrations of V, As and Mo was extracted from almost all four materials. The red processed shale released the highest percentages of its total contents of V, As and Mo under these conditions; 28 %, 55 % and 61 % respectively. The high release of V, As and Mo from red processed shale was most likely a result from the pyrolysis process. The roasting induced the formation of oxides which then easily forms vanadate, arsenate and molybdate when exposed to water. Water percolating the Kvarntorp deposit in the future will initially most likely have a near neutral or slightly acidic pH. Lowest concentrations of metals were found in aqueous samples with pH between 5.5-8.5. There is a great risk that the pH of the drainage from the Kvarntorp deposit will in time become acidic due to depletion of buffering capacity. Thus the environmental threat will increase.
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Gabagnou, Catherine, Jens Fennen, and Daniel Herta. "Modern unhairing technologies for effective control of H2S release from Beamhouse operations - 55." Verein für Gerberei-Chemie und -Technik e. V, 2019. https://slub.qucosa.de/id/qucosa%3A34335.

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Content: The toxicity and unpleasant smell of hydrogen sulphide (H2S) gas is an issue for the leather industry that has been contained rather than eliminated in tannery practice. Completely eliminating H2S from tanneries while maintaining practical and economically feasible processing is still a big challenge to be addressed. Significant progress has, though, been made by introducing robust and reliable low sulphide unhairing systems based on selective soaking and specific enzymatic liming auxiliaries. These systems allow the reduction of sodium sulphide offers from the typical 2.5% to 1% of pelt weight. These lower levels reduce the amount of hydrogen sulphide gas released into the environment from the liming float, as well as the amount of sulphide that is carried over in the hide to subsequent processing steps. Overall, the H2S problem is not eliminated, but significantly reduced with this technology. In a further evolution of the technology, organic thio compounds can be used to fully or partially replace the already low levels of sulphide required, and thus allow to operate with offers well below 1%, or even completely without inorganic sulphide. Due to their reductive power, the organic thio compounds react with keratin in a similar way as inorganic sulphides, but they are oxidized much faster, which is advantageous for the effluent load. Alternatively to, or in combination with organic thio compounds, H2S scavengers can be used to reduce or eliminate hyrogen sulphide released from liming floats. Different types of scavengers are available, but the selection is limited for technical and economic reasons. The paper on hand shows how the release of hydrogen sulphide from beamhouse operations can be effectively controlled by a combination of technologies involving more effective unhairing with lower amounts of reductive agents, replacement of inorganic sulphide by organic thio compound and the use of H2S scavengers. Take-Away: - The release of toxic H2S from Beamhouse operations can be effectively controlled using modern unhairing technologies allowing to use no or low sulphide. - These modern unhairing systems are based on a combination of selective soaking, unhairing assisted by enzymes with specific activity and the use of organic thio compounds.
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Maleki, Rahil. "Consequences Analysis of CH4/H2S Release in Offshore Platform." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.

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The exploitation and development of offshore oil & gas fields continue to be one of the main source to supply energy worldwide. However, existing and new projects may involve specific geographic areas with safety challenges due to the presence of natural gas, mainly Methane (CH4), containing a certain amount of Hydrogen Sulphide (H2S) in the extracted hydrocarbons (sour gas). Indeed, the combined effect of flammability and toxicity of such gases has the critical potential to increase the hazard level in the offshore installation aggravating the consequences for human and assets. The present work aims at the consequences analysis related to the release of sour gas (CH4/H2S) on an offshore production facility, by considering different H2S fractions in the gas composition. The analysis was based on the estimation of safety distances for the physical effects of accident scenarios with respect to personnel, equipment and facility structures. Two different approaches implemented into consequences modelling software, the Process Hazard Analysis Software Tool (PHAST), which is based on integral and lumped parameter model, and the Fire Dynamic Simulator (FDS), which is ascribed to the Computational Fluid Dynamic model, hence based on distributed parameter model. A case study concerning an actual offshore, multi-level platform for gas production was considered. Large releases from two different process equipment were simulated for three mixtures with different amount of H2S, starting from specific release points. The results showed that the H2S content is not an effective factor for the safety distance in the case of ignition of the gas cloud, hence in the case of fires. Also, the presence of obstructions slightly affects the damage distances for fires. On the contrary, the safety distance from the release point can be strongly affected by the presence of H2S concentration higher than 1%v.
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Chaibva, Faith Anesu. "The use of response surface methodology and artificial neural networks for the establishment of a design space for a sustained release salbutamol sulphate formulation." Thesis, Rhodes University, 2010. http://hdl.handle.net/10962/d1010432.

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Quality by Design (QbD) is a systematic approach that has been recommended as suitable for the development of quality pharmaceutical products. The QbD approach commences with the definition of a quality target drug profile and predetermined objectives that are then used to direct the formulation development process with an emphasis on understanding the pharmaceutical science and manufacturing principles that apply to a product. The design space is directly linked to the use of QbD for formulation development and is a multidimensional combination and interaction of input variables and process parameters that have been demonstrated to provide an assurance of quality. The objective of these studies was to apply the principles of QbD as a framework for the optimisation of a sustained release (SR) formulation of salbutamol sulphate (SBS), and for the establishment of a design space using Response Surface Methodology (RSM) and Artificial Neural Networks (ANN). SBS is a short-acting ♭₂ agonist that is used for the management of asthma and chronic obstructive pulmonary disease (COPD). The use of a SR formulation of SBS may provide clinical benefits in the management of these respiratory disorders. Ashtalin®8 ER (Cipla Ltd., Mumbai, Maharashtra, India) was selected as a reference formulation for use in these studies. An Ishikawa or Cause and Effect diagram was used to determine the impact of formulation and process factors that have the potential to affect product quality. Key areas of concern that must be monitored include the raw materials, the manufacturing equipment and processes, and the analytical and assessment methods employed. The conditions in the laboratory and manufacturing processes were carefully monitored and recorded for any deviation from protocol, and equipment for assessment of dosage form performance, including dissolution equipment, balances and hardness testers, underwent regular maintenance. Preliminary studies to assess the potential utility of Methocel® Kl OOM, alone and in combination with other matrix forming polymers, revealed that the combination of this polymer with xanthan gum and Carbopol® has the potential to modulate the release of SBS at a specific rate, for a period of 12 hr. A central composite design using Methocel® KlOOM, xanthan gum, Carbopol® 974P and Surelease® as the granulating fluid was constructed to fully evaluate the impact of these formulation variables on the rate and extent of SBS release from manufactured formulations. The results revealed that although Methocel® KlOOM and xanthan gum had the greatest retardant effect on drug release, interactions between the polymers used in the study were also important determinants of the measureable responses. An ANN model was trained for optimisation using the data generated from a central composite study. The efficiency of the network was optimised by assessing the impact of the number of nodes in the hidden layer using a three layer Multi Layer Perceptron (MLP). The results revealed that a network with nine nodes in the hidden layer had the best predictive ability, suitable for application to formulation optimisation studies. Pharmaceutical optimisation was conducted using both the RSM and the trained ANN models. The results from the two optimisation procedures yielded two different formulation compositions that were subjected to in vitro dissolution testing using USP Apparatus 3. The results revealed that, although the formulation compositions that were derived from the optimisation procedures were different, both solutions gave reproducible results for which the dissolution profiles were indeed similar to that of the reference formulation. RSM and ANN were further investigated as possible means of establishing a design space for formulation compositions that would result in dosage forms that have similar in vitro release test profiles comparable to the reference product. Constraint plots were used to determine the bounds of the formulation variables that would result in the manufacture of dosage forms with the desired release profile. ANN simulations with hypothetical formulations that were generated within a small region of the experimental domain were investigated as a means of understanding the impact of varying the composition of the formulation on resultant dissolution profiles. Although both methods were suitable for the establishment of a design space, the use of ANN may be better suited for this purpose because of the manner in which ANN handles data. As more information about the behaviour of a formulation and its processes is generated during the product Iifecycle, ANN may be used to evaluate the impact of formulation and process variables on measureable responses. It is recommended that ANN may be suitable for the optimisation of pharmaceutical formulations and establishment of a design space in line with ICH Pharmaceutical Development [1], Quality Risk Management [2] and Pharmaceutical Quality Systems [3]
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Jowitt, Simon Martin. "Field, petrological and geochemical constraints on the release of base metals into hydrothermal fluids in Cyprus-type Volcanogenic Massive Sulphide (VMS) systems : an investigation of the Spilia-Kannavia epidosite zone, Troodos ophiolite, Cyprus." Thesis, University of Leicester, 2009. http://hdl.handle.net/2381/7689.

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Understanding source-deposit relationships in VMS systems is important for mineral exploration and to increase knowledge of seafloor hydrothermal processes and ocean–crust fluxes. Although it is known that metals are stripped from oceanic crust by hydrothermal fluids and redeposited in orebodies, some aspects are poorly understood. It has been proposed that metal depleted epidosites (epidote–quartz–chlorite–Fe-oxide–titanite units within sheeted dyke complexes) are source rocks for Cyprus-type VMS deposits. To test this hypothesis, the Spilia-Kannavia epidosite zone in the Troodos ophiolite, Cyprus, was investigated. This zone (≥1.9 km3), at the base of the Sheeted Dyke Complex, extends ~5 km parallel and ~2 km across dyke strike and vertically ≥400 m. Differentiation trends defined by LA-ICP-MS analysis of volcanic glass and SIMS analysis of minerals in fresh basalts indicate that olivine and pyroxene were important hosts of Co, Ni and Mn but not Cu or significant Zn. Protoliths for the Spilia-Kannavia epidosite zone were Zn rich, with moderate Mn and Co and low Cu and Ni relative to average Troodos basalts. SIMS analysis indicates that, during epidositisation, chlorite and amphibole are the only silicate minerals that retain Co, Ni and Zn, whilst epidote hosts Mn. Concentrations of Cu are low in all silicates. Base metal mobilisation was controlled by chlorite and amphibole dissolution although concentrations in chlorite and epidote vary with alteration. During alteration, the Spilia-Kannavia epidosite zone released ~0.4 Mt Zn, ~0.06 Mt Ni, ~5.2 Mt MnO, and 0.14 Mt Cu. This exceeds the Zn within any Cyprus-type VMS deposit, and provides enough Cu for a medium-large deposit. In comparison, published data suggest a similar volume of non-epidosite zone diabase could mobilise similar amounts of Zn, less Cu and Ni, and no Co or Mn, but it is not clear if all of these base metals are removed from the sheeted dyke complex. It is concluded that the epidosite zone formation is the only way to mobilise significant amounts of base metals within Cyprus-type VMS systems.
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Boonsongsup, Lerssak. "SO��� capture and HCl release at Kraft recovery boiler conditions." Thesis, 1993. http://hdl.handle.net/1957/35778.

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Books on the topic "Sulphate released"

1

Dohoo, Susan. Pharmacokinetics of parentral morphine sulphate and oral sustained release morphine sulphate in dogs. National Library of Canada, 1991.

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Dohoo, Susan. Pharmacokinetics of parentral morphine sulphate and oral sustained release morphine sulphate in dogs. University of Prince Edward Island, 1991.

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Alberta. Energy Resources Conservation Board, ed. A Technical study of shelter versus evacuation when faced with a release of hydrogen sulphide. Alberta Public Safety Services, 1992.

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Southwood, M. J. Mineralogical aspects of the bacterial leeching of auriferous sulphide concentrates, and a mathematical model for the release of gold. Council for Mineral Technology, 1986.

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Boonsongsup, Lerssak. SC capture and HCl release at Kraft recovery boiler conditions. 1993.

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Carangal, Aimee B. The release of NO during black liquor pyrolysis. 1994.

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Reis, Victor Vinicius. Potassium and chloride release during black liquor combustion. 1994.

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Agency, Environment. Monitoring Hydrogen Sulphide and Total Reduced Sulphur in Atmospheric Releases and Ambient Air (Technical Guidance Note (Monitoring)). Stationery Office Books, 2002.

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Book chapters on the topic "Sulphate released"

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Bernardino, Misael Morales. "When a Mining Company Releases of Copper Sulphate Acid Solution into the Environment." In Green Crime in Mexico. Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-75286-0_14.

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Falikman, V. R., K. B. Safarov, and V. F. Stepanova. "Effect of Alite Content in Sulphate-Resistant Cement on Heat Release in Massive Hydraulic Engineering Structures." In Concrete Durability and Service Life Planning. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-43332-1_27.

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Jahn, Silvia, Michael Paul, and Delf Baacke. "Contaminant Release and Carbonate Availability of Sulphide-Bearing Waste Rock derived from Long-term Column Tests." In Uranium in the Aquatic Environment. Springer Berlin Heidelberg, 2002. http://dx.doi.org/10.1007/978-3-642-55668-5_47.

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Giordani, Gianmarco, Marco Bartoli, Matteo Cattadori, and Pierluigi Viaroli. "Sulphide release from anoxic sediments in relation to iron availability and organic matter recalcitrance and its effects on inorganic phosphorus recycling." In Coastal Lagoon Eutrophication and ANaerobic Processes (C.L.E.AN.). Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-009-1744-6_17.

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"Release kinetics of tobramycin sulphate from polymethylmethacrylate implants." In Pharmaceutical Technology: Controlled Drug Release Vol 2. CRC Press, 1991. http://dx.doi.org/10.3109/9780203979099-26.

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Reyes Alvarado, Luis Carlos. "Carbohydrate based polymeric materials as slow release electron donors for sulphate removal from wastewater." In Optimization of the electron donor supply to sulphate reducing bioreactors treating inorganic wastewater. CRC Press, 2018. http://dx.doi.org/10.1201/9780429439209-8.

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Okoth, Kevin Otieno, Ruth Nduta Wanjau, and Maurice Otieno Odago. "Semiconductor Nanocomposites-Based Photoelectrochemical Aptamer Sensors for Pharmaceuticals Detection." In Advances in Environmental Engineering and Green Technologies. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1871-7.ch007.

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Development of sensors for pharmaceuticals has become very essential. This is due to the need to monitor the release and toxicological effects of pharmaceuticals into the environment. In this work, the authors explored bismuth sulphide (Bi2S3) nanorods and graphene as photoactive material for constructing a photoelectrochemical (PEC) aptasensor for sulfadimethoxine (SDM) detection, exhibiting high sensitivity, stability, and reproducibility. In another experiment, Mo-doped BiVO4 (Mo-BiVO4) and graphene nanocomposites were explored as photoactive material to construct a visible light-driven photoelectrochemical biosensor. Graphene in the nanocomposites was very essential in immobilizing streptomycin aptamer through π-π stacking interaction. Finally, graphene doped CdS (GR-CdS) synthesized via one pot hydrothermal technique and gold nanoparticles (Au NPs) were employed to construct a PEC aptasensor for diclofenac (DCF).
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Okoth, Kevin Otieno, Ruth Nduta Wanjau, and Maurice Otieno Odago. "Semiconductor Nanocomposites-Based Photoelectrochemical Aptamer Sensors for Pharmaceuticals Detection." In Research Anthology on Synthesis, Characterization, and Applications of Nanomaterials. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-8591-7.ch030.

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Development of sensors for pharmaceuticals has become very essential. This is due to the need to monitor the release and toxicological effects of pharmaceuticals into the environment. In this work, the authors explored bismuth sulphide (Bi2S3) nanorods and graphene as photoactive material for constructing a photoelectrochemical (PEC) aptasensor for sulfadimethoxine (SDM) detection, exhibiting high sensitivity, stability, and reproducibility. In another experiment, Mo-doped BiVO4 (Mo-BiVO4) and graphene nanocomposites were explored as photoactive material to construct a visible light-driven photoelectrochemical biosensor. Graphene in the nanocomposites was very essential in immobilizing streptomycin aptamer through π-π stacking interaction. Finally, graphene doped CdS (GR-CdS) synthesized via one pot hydrothermal technique and gold nanoparticles (Au NPs) were employed to construct a PEC aptasensor for diclofenac (DCF).
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Reyes Alvarado, Luis Carlos. "Lignocellulosic biowastes as carrier material and slow release electron donor for sulphidogenesis of wastewater in an inverse fluidized bed bioreactor." In Optimization of the electron donor supply to sulphate reducing bioreactors treating inorganic wastewater. CRC Press, 2018. http://dx.doi.org/10.1201/9780429439209-9.

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Linklater, C., P. Irannejad, P. Brown, A. Pekdeger, and C. Kohfahl. "Long-term predictions of sulphate release by pyrite weathering from heap sediments into the ground- and surface water." In Water-Rock Interaction. Taylor & Francis, 2007. http://dx.doi.org/10.1201/noe0415451369.ch69.

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Conference papers on the topic "Sulphate released"

1

Maggi, A., T. W. Barrowcliffe, E. Gray, M. B. Donati, R. E. Merton, and I. Pangrazzi. "RELATIONSHIP BETWEEN HAEMORRHAGIC AND LIPASE-RET EASING PROPERTIES OF HEPARIN AND LMV HEPARIN." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1642929.

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In a preliminary study, a good correlation (r = 0.97) was noted between the relative abilities of an unfractionated heparin, a LMW heparin, pentosan poly sulphate and dermatan sulphate to prolong the template bleeding time in rabbits and their lipase-releasing potencies. In the present study, we have measured the prolongation of both the template and transection bleeding times in groups of 5 rats given i.v. injections of 0.75 mg/kg of two different unfractionated heparins (UEH), A and B, three different LMW heparins, X, Y and Z, and a heparan sulphate, HS. Lipase release was measured in plasma samples from different groups of 5 rats, using a tritiated triolein method.UFH A had the most haemorrhagic effect, with an approximate doubling of both template and transection bleeding times and was also the most potent lipase-releaser, giving an average lipase level of 1126 mu/ml. UFH B had no significant effect on the template bleeding time, but did prolong the transection time; its lipase releasing potency was 70% of UFH A. IMW heparin X had no effect on template or transection bleeding time and released only 40% lipase compared with UEH A. LMW heparins Y and Z did not affect the template bleeding time but did prolong the transection time; they released more lipase (60%) than LMW heparin X. Correlation coefficients with lipase release were 0.97 for the template bleeding time and 0.69 for the transection bleeding time. HS released only 7% lipase but gave significant prolongations of both bleeding times.These results confirm a strong positive correlation between the haemorrhagic and lipase releasing properties of heparin and LMW heparin, suggesting very similar structural requirements for the two biological activities. This correlation exists also for dermatan sulphate and pentosan polysulphate, but not for the heparan sulphate sample tested.
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Mussoni, L., M. Abbadini, G. J. Zhu, A. Maggi, J. Pangrazzi, and M. B. Donati. "DERMATAN SULPHATE (DS) INDUCES t-PA RELEASE IN THE PERFUSED RAT HINDQUARTERS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643242.

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Previous studies have shown that heparin and related glycosaminoglycans (GAGs) were able to Induce the release of plasminogen activator (PA) activity In perfusion models. Among GAGs, DS has recently attracted Interest due to Its antithrombotic effect devoid of haemorrhaglc complications In experimental models of venous thrombosis. We report here that highly purified DS (MF-701, Mediolanum Farmaceutici, Milano, Italy) is able to induce t-PA activity release. Non heparlnlzed animals were perfused with oxygenated Tyrode’s solution at a constant flow rate of 10 ml/min. PA activity of the perfusate (collected at various time Intervals from vena cava) was measured by a fibrin plate method and expressed as mtl/ml by comparison with a reference curve of standard t-PA (WHO). Three minutes perfusion of different doses of DS (0.1, 0.2, 0.4 mg/ml) Induces a dose-dependent Increase in PA, activity (from 35 to 60, 99, 127 mU/ml respectively), being maximal during the first and second minute of drug perfusion. A further increase In DS concentration (0.6-0.8 mg/ml) resulted in an inhibition of PA activity released. The PA activity present In the perfusate of animals treated with 0.4 mg/ml DS has been characterized as associated with t-PA-like molecules on the basis of the relative mobility In SDS-PAGE followed by fibrin autography (67,000 m.w.) and inhibition by an antiserum against t-PA In this system. This effect was peculiar for DS, since none of the HMW heparlns tested induced PA activity release In this experimental model. These data may suggest that during “In vivo” infusion of DS In a thromboembolic condition some t-PA could be released from the endothelial cells and bind to fibrin In the thrombus to favour its dissolution.
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Dave´, Nand K. "Mobility of Ra-226 and Heavy Metals (U, Th and Pb) From Pyritic Uranium Mine Tailings Under Sub-Aqueous Disposal Conditions." In ASME 2011 14th International Conference on Environmental Remediation and Radioactive Waste Management. ASMEDC, 2011. http://dx.doi.org/10.1115/icem2011-59283.

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Laboratory lysimeter studies were undertaken to evaluate the leaching characteristics and mobility of Ra-226 and other heavy metals (U, Th and Pb) from pyritic uranium mine tailings under sub-aqueous disposal conditions for assessing the long-term radiological stability of such waste repositories. The experiments were conducted using three types of un-oxidized tailings: fine, coarse and gypsum depleted mill total tailings. The results showed that Ra-226 was leached from surface of the submerged tailings and released to both surface water and shallow zone pore water during initial low sulphate ion concentration of the surface water cover in all three cases. The release of Ra-226 was further enhanced with the onset of weak acidic conditions in the surface water covers of both coarse and gypsum depleted mill total tailings. With additional acid generation and increasing sulphate and iron concentrations, the dissolved Ra-226 concentrations in the water covers of these tailings gradually decreased back to low levels. Pb was also leached and mobilized with the development of moderate acidic conditions at the surface of the submerged coarse and gypsum deplete tailings. No leaching of U and Th was observed.
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Fjelde, Ingebret. "Sulphate in Original Reservoir Chalk Rocks: Release of Sulphate by Desulphated Sea Water and Effects on Wettability." In SPE Europec featured at 80th EAGE Conference and Exhibition. Society of Petroleum Engineers, 2018. http://dx.doi.org/10.2118/190844-ms.

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Xing, Yage, Xihong Li, Qinglian Xu, Juan Yun, Yaqing Lu, and Jing Wang. "SO2-Release Performances of Sulphite Microparticles under Different Relative Humidity: SO2-Release Performance." In 2010 4th International Conference on Bioinformatics and Biomedical Engineering (iCBBE). IEEE, 2010. http://dx.doi.org/10.1109/icbbe.2010.5516685.

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Gottberg, I., E. Högberg, and K. Weber. "Sulphur Storage and Hydrogen Sulphide Release from a Three-Way Catalyst Equipped Car." In SAE International Congress and Exposition. SAE International, 1989. http://dx.doi.org/10.4271/890491.

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Barre´, Yves, and Vincent Pacary. "Study of the Radioactive Liquid Waste Treatment by Coprecipitation: From Modeling to New Process Designs." In ASME 2009 12th International Conference on Environmental Remediation and Radioactive Waste Management. ASMEDC, 2009. http://dx.doi.org/10.1115/icem2009-16018.

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The ever increasing pressure to reduce the release of radioactive and other toxic substances into environment requires constant improvement/upgrading of processes and technologies for treatment and conditioning of liquid radioactive wastes. To decontaminate liquid nuclear wastes, the coprecipitation process is the most commonly used in nuclear field because it can be applied to any type of aqueous effluents whatever their composition may be. This process deals with the in situ precipitation of solid particles to selectively remove one or more radioelements. In the nuclear research center of CEA (Commissariat a` l’Energie Atomique), the coprecipitation of 90Sr with barium sulphate is the technique used to treat selectively this radionuclide. In a previous study (1), an elaborated model is presented which predicts the radioactive strontium decontamination factor of nuclear waste solutions which can be achieved by using a coprecipitation process with barium sulphate. The originality of this new approach lies in the possibility to simulate the decontamination process in non equilibrium conditions and at the reactor scale. This modelling combined with the resolution of the population balance, enables to identify the influence of process parameters (flow rates, stirring speed…) on crystal size and ultimately on decontamination. Simulations of the strontium coprecipitation with barium sulphate have been performed in continuous and semi batch reactors. Thanks to these simulations, laws of the treatment efficiency variation as a function of several process parameters (mean residence time, stirring speed, BaSO4 concentration) have been determined and experimentally verified. This study leads to the determination of optimal treatment conditions. Three apparatus (recycling apparatus, fluidised bed and reactor/settling tank) providing these optimal conditions have been successfully tested and offered significant outlooks for the reduction of the residual sludge volume.
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Montell, E., TV Stabler, and VB Kraus. "THU0044 Chondroitin sulphate inhibits monocyte chemoattractant protein-1 release from 3T3L1 adipocytes: a new treatment opportunity for obesity-related metabolic syndromes?" In Annual European Congress of Rheumatology, 14–17 June, 2017. BMJ Publishing Group Ltd and European League Against Rheumatism, 2017. http://dx.doi.org/10.1136/annrheumdis-2017-eular.2140.

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Patterson, D., W. Williams, M. Jordan, and R. Douglas. "Pre-Production Deployed Scale Inhibition Treatments in Deep-Water, West Africa." In SPE International Oilfield Scale Conference and Exhibition. SPE, 2014. http://dx.doi.org/10.2118/spe-169784-ms.

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Abstract The injection of seawater into oil-bearing reservoirs in order to maintain reservoir pressure and improve secondary recovery is a well-established, mature operation. Moreover, the degree of risk posed by deposition of mineral scales (carbonate/sulphate) to the injection and production wells during such operations has been much studied. The current deep-water subsea developments offshore West Africa and Brazil have brought into sharp focus the need to manage scale in an effective way. In a deepwater West African field the relatively small number of high-cost, highly productive wells, coupled with a high barium sulphate scaling tendency upon breakthrough of injection seawater meant not only was effective scale management critical to achieve high hydrocarbon recovery, but even wells at low water cuts have proven to be at sufficient risk to require early squeeze application. To provide effective scale control in these wells at low water cuts, phosphonate-based inhibitors were applied as part of the acid perforation wash and overflush stages prior to frac packing operations. The deployment of this inhibitor proved effective in controlling barium sulphate scale formation during initial water production eliminating the need to scale squeeze the wells at low water cuts (<10% BS&W). To increase the volumes of scale inhibitor being deployed in the pre-production treatments and so extend the treatment lifetimes scale inhibitor was also added to the frac gel used to carry the frac sand. This paper outlines the selection methods for the inhibitor chemical for application in frac fluids in terms of rheology, retention/release, formation damage and presents the chemical returns profile from the 5 wells treated (some treatments lasting > 300 days) along with monitoring methods utilized to confirm scale control in the wells treated. Many similar fields are currently being developed in the Campos basin, Gulf of Mexico, and West Africa, and this paper is a good example of best-practice sharing from another oil basin.
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Celia, G., M. Prosdocimi, and A. A. Sasahara. "IN VIVO INTERACTION BETWEEN HUMAN PLATELET FACTOR 4 (PF4) AND PROTAMINE SULPHATE (PS) IN THE PRESENCE OF DIFFERENT GLYCOSAMI-NOGLYCANS (GAGs)." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643501.

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Anti-heparin substances, like PF4 or PS, have been studied largely in reference to their ability to neutralize the anticoagulant activity of heparin. On the other hand, few data are available concerning the relationship between GAGs and anti-heparin proteins clearance. We studied the action of PS on human PF4 kinetics in anesthetized rabbits pre-treated with heparin (H, 1000 I.U.), heparan sulphate (HS, 30 mg) and derma tan sulphate (DS, 30 mg). PF4 (given at a dose of 45 μgAg) disappearance reflected its different affinity for the GAGs, with the following half lives (min): control 2.09±0.28, H 14.80±1.47, HS 10.90±1.91, DS 6.87±0.68. Moreover, circulating PF4 (ng/ml) at 1 min was as follows: control 109±8, H 873±134, HS 751±34 and DS 473±15. In another group of H pre-treated rabbits, a bolus injection of PS (10 or 20 mg) caused an immediate disappearance in th.e circulating plasma PF4, from 900±23 ng/ml (1 min after PF4) to 75±11 ng/ml (1 min after 10 mg PS). However, a subsequent H injection 10 min after PS induced a peak release of PF4 (520±21 ng/ml). In a further group of animals pre-treated with HS, the interaction between PS and PF4 was similar to that observed after H treatment. In the last group, pre-treated with DS, the interaction between PF4 and PS was also similar, however, unexpectedly, when 20 mg of PS were given a subsequent bolus of H did not produce any increase of circulating PF4We suggest that PS displaces PF4 from its binding sites on H or HS, thus allowing its uptake by the storage sites in the body, from where it can be harvested again after the subsequent H administration. In the presence of DS again PS is able to displace PF4, however the remaining excess of PS could neutralize the subsequent H injection, thus rendering it unable to induce PF4 release.
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