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Academic literature on the topic 'Chemical contents'

Author: Grafiati

Published: 5 June 2025

Last updated: 24 June 2025

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Journal articles on the topic "Chemical contents"

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"Contents and Chemical Science." Chemical Society Reviews 38, no. 7 (2009): 1827. http://dx.doi.org/10.1039/b911088g.

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"Contents and Chemical Technology." CrystEngComm 11, no. 7 (2009): 1159. http://dx.doi.org/10.1039/b911206p.

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"Contents and Chemical Technology." Analyst 134, no. 7 (2009): 1251. http://dx.doi.org/10.1039/b911238n.

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"Contents and Chemical Technology." Chemical Communications, no. 26 (2009): 3815. http://dx.doi.org/10.1039/b911250m.

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"Contents and Chemical Technology." Journal of Materials Chemistry 19, no. 26 (2009): 4439. http://dx.doi.org/10.1039/b911299p.

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"Contents and Chemical Technology." Dalton Transactions, no. 26 (2009): 5039. http://dx.doi.org/10.1039/b911320g.

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"Contents and Chemical Biology." Natural Product Reports 26, no. 7 (2009): 859. http://dx.doi.org/10.1039/b911406h.

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"Contents and Chemical Technology." Physical Chemistry Chemical Physics 11, no. 26 (2009): 5207. http://dx.doi.org/10.1039/b911418c.

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"Contents and Chemical Technology." Journal of Analytical Atomic Spectrometry 24, no. 7 (2009): 851. http://dx.doi.org/10.1039/b911422j.

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"Contents and Chemical Technology." Energy & Environmental Science 2, no. 7 (2009): 715. http://dx.doi.org/10.1039/b911443m.

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Dissertations / Theses on the topic "Chemical contents"

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Morcom, Andrea R. "PH responsive polymers for controlled release of liposomal contents." Thesis, Aston University, 2004. http://publications.aston.ac.uk/9658/.

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SOUZA, RODRIGO FERNANDES M. DE. "CHEMICAL PROCESSING OF SULFIDE CONCENTRATES WITH HIGH AND LOW COPPER CONTENTS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33315@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO<br>COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR<br>CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO<br>PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO<br>Concentrado minerais sulfetados são uma importante fonte de matérias-primas nos processos de extração de metais não-ferrosos. No que diz respeito ao cobre, estes são usualmente processados segundo um fluxograma contemplando as etapas de ustulação, fusão mática, conversão e refino. Todavia, algumas características dos concentrados podem limitar a sua aceitação nas plantas de processamento tais como: baixo teor de cobre assim como a presença de elementos ditos deletérios, como, por exemplo, o flúor e seus efeitos corrosivos sobre materiais refratários após a transformação e ácido fluorídrico; ainda que o material possua um teor do metal de interesse elevado. Dentro desse contexto, o presente trabalho tem por objetivo avaliar o processamento químico de concentrados sulfetados de cobre com essas características a fim de entender o seu comportamento nos processos de ustulação, visando à identificação de condições que minimizem os efeitos danosos do flúor, no caso de concentrados de alto, assim como determinar uma janela operacional que possibilite a obtenção seletiva de CuSO4, no caso de concentrados de baixo teor. Para atender a esses objetivos, foi levado a efeito um estudo teórico incluindo uma breve revisão da literatura e uma apreciação termodinâmica das reações químicas mais relevantes em cada sistema reacional. O estudo experimental foi conduzido através da avaliação do efeito de variáveis específicas para cada sistema reacional. No caso particular de concentrados de alto teor contendo flúor, os experimentos contemplaram a presença, ou não, de água na atmosfera reacional ao passo que nos ensaios envolvendo concentrados de baixo teor de cobre foram levados a efeito variando a temperatura e a composição química da atmosfera reacional a partir da recirculação de parte dos produtos gasosos, como, por exemplo, o SO2. Os materiais envolvidos foram caracterizados por meio de microscopia eletrônica de varredura e difração de raios-x. As previsões teóricas de ambos os sistemas reacionais puderam ser confirmadas na caracterização dos produtos reacionais obtidos após o processamento químico dos concentrados sulfetados de alto e baixo teor de cobre. No que tange o primeiro destes, observou-se que o flúor tende a permanecer estável na forma de fluorita quando na ausência de umidade no sistema reacional. Por outro lado, no que diz respeito ao último destes materiais, verificou-se que o reciclo de parte dos produtos gasosos do processo é responsável por uma melhora de desempenho da reação química de ustulação visando à formação seletiva de sulfato de cobre e óxido de ferro.<br>Sulfide minerals concentrates are an important source of raw materials for non-ferrous metals extraction processes. For copper, these are usually processed through a flowchart containing the operations of roasting, matte smelting, conversion and refining. However, some concentrates characteristics may limit its acceptance in processing plants such as low copper content and the presence of deleterious elements, such as fluorine and its corrosive effects as result of its transformation into hydrofluoric acid; even if the metal content is this material is high. Within this context, this study aims to evaluate the chemical processing of sulfide concentrates with these characteristics in order to understand their roasting behavior, in order to identify conditions that minimize the fluorine harmful effects for concentrate with high copper content, and determine an operating window that allows the selective obtainment of CuSO4, for low grade concentrates. To meet these objectives, it was carried out a theoretical study including a brief review of the literature and a thermodynamics assessment of the most important chemical reactions in each reaction system. The experimental study was conducted evaluating the effect of specific variables for each reaction system. In the case of concentrates of high grade containing fluorine, the experiments contemplate the presence or absence of water in the reaction atmosphere while the tests involving the concentrate with low copper content were carried out by varying the temperature and the chemical composition of the atmosphere, recirculating part of the gaseous products, like SO2. The materials were characterized by scanning electron microscopy and x-ray diffraction. The theoretical predictions of both reaction systems could be confirmed in the characterization of the reaction products obtained after the chemical processing of sulfide concentrates of high and low copper content. In what touches the former, it was observed that fluorine tends to remain stable as fluorite in the absence of moisture within the reaction system. On the other hand, regarding the latter material, it was found that the part of recycled gaseous products of the process are responsible for a performance improvement of the roasting reaction focused on the selective formation of copper sulfate and iron oxide.

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Einar, Lidén. "Chemical Analysis of the Contents of Ancient Kohl Pots from the Nubian Kingdom." Thesis, Uppsala universitet, Institutionen för kemi - BMC, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-443282.

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Nilsson, Linnea, and Sahra Svensson. "Consumer product contents information from the 1st tier supplier : Obstacles to 1st tier supplier compliance to product contents information requirements and useful supply chain management practices to ensure supplier compliance." Thesis, Blekinge Tekniska Högskola, Institutionen för industriell ekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-13040.

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Purpose: The purpose of this thesis is to identify the obstacles against supplier compliance, which focal companies encounter within the upstream supply chain when attempting to collect the requested product contents information. Based on this problem, the objective is to identify the most useful supply chain management practices to ensure supplier compliance.Method: The theoretical framework contains the Principal-Agent theory and Responsible Supply Chain Management. The empirical findings are derived through semi-structured interviews that were conducted with three Swedish corporations operating in China and one Swedish-Chinese consulting firm.Results: The two main-obstacles to supplier compliance were firstly found to consist of lacking supplier understanding of the product contents information requirements (PCIR). These obstacles prevented the supplier from understanding the risk at hand and what behaviour that triggered the risk. The second main-obstacles were found to be the prevalence of different opposing interests, which could all be traced back to the reluctance to assume an increase in costs, and could induce the supplier to pursue that interest rather than the interest to comply to the PCIR. With these obstacles in mind, the main objective of the focal company’s supply chain management practices should preferably be to create risk in relation to the PCIR, ensure supplier understanding and pay attention to the opposing interests. The most useful type of supply chain management practice for fulfilling these objectives were the use of incentives, preferably in combination with sanctions, to create risk. Training was considered most useful for ensuring supplier understanding, although a combination of training, personal communication and written documents is potentially interesting. Regarding the opposing interests, accommodating practices were found most useful rather than attempt to persuade the supplier to give up the interest.

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Fard, Ebrahim Rowghani Haghighi. "Chemical and nutritional characteristics of whole-crop barley ensiled at different dry matter contents with or without silage additives." Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307930.

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Zaidi, Syed Faraz Ali, and Juthatip Sudthanom. "To Analyze The Relationship between BOD, Nitrogen And Phosphorus Contents at Constant Dissolved Oxygen Concentration In Municipal Wastewater Treatment." Thesis, Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-12524.

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In this report, the application of Principle Component Analysis (PCA) and Partial Least Square (PLS) regression analyzing methods used to understand the relationship of interdependent loads in municipal wastewater treatment plant. Two different wastewater treatment plants were chosen for analysis of the relationship between interdependent loads. Firstly, the collected data of incoming wastewater and outgoing water from both Västerås and Eskilstuna wastewater treatment plants were analyzed to find some relationship or correlation between contents and compare the data of both the plants. Secondly, the correlated contents were used to generate the regression model for predicting the value in the future, in this report we have focussed only on ammonium nitrogen value for regression model. The PCA study shows the variation between incoming and outgoing wastewater’s characteristics given by Västerås and Eskilstuna plant.<br>BOD, ammonium nitrogen, nitrogen, phosphorus

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Mahfouz, Céline. "An assessment of the chemical contamination and the diet changes of the harbou porpoise (Phocoena phocoena) stranded along the southern North Sea." Thesis, Littoral, 2014. http://www.theses.fr/2014DUNK0433/document.

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De part l'importance et la diversité des pressions anthropiques en mer du Nord, les mammifères marins en tant que prédateurs supérieurs se trouvent de plus en plus exposés à ces activités (trafic maritime, activités industrielles et portuaires, surpêche, pollution chimique, etc.). Les campagnes d'observation SCANS et SCANS II mises en place en 1994 et 2005 pour estimer l'abondance des petits cétacés, ont mis en évidence un changement majeur dans la distribution du marsouin commun (Phocoena phocoena) en mer du Nord avec un déplacement du Nord vers le Sud. Ce changement peut être lié à une migration de ses proies préférentielles en mer du Nord et/ou à une afaptation de son régime alimentaire par rapport à la disponibilité des proies. Parallèlement, à ces modifications de distribution spatiale, un nombre croissant d'échouage de marsouin commun en Manche Orientale et sur les côtes belges a été observé depuis une dizaine d'années avec une augmentation conséquente ces deux dernières années. Pour étudier les causes responsables de ces échouages, un des objectifs de cette étude a été d'évaluer l'état de la contamination chimique des animaux échoués en relation avec l'état sanitaire des individus. L'analyse de deux familles de composés chimiques (éléments traces métalliques et polluants organiques persistants) sur des animaux échoués sur la période 2006-2013 révèlent des concentrations significativement plus élevées dans les organies des animaux présentant des pathologies que celles obtenues chez les animaux sains. Cette tendance a déjà été observée en Atlantique Nord pour le marsouin. Les comparaisaons des niveaux de concentration mesurées avec ceux d'études antérieures effectuées sur des marsouins échoués dans la même zone ou dans le Golfe de Gascogne suggèrent que l'augmentation du nombre de marsouins échoués n'est pas liée à une dégradation du milieu en terme de pollution chimique. Pour déterminer le régime alimentaire du marsouin commun, trois techniques complémentaires ont été utilisées : l'analyse des contenus stomacaux, des isotopes stables (carbone et azote) et des acides gras dans différents tissus. Pour ces deux dernières méthodes, les signatures obtenues pour le marsouin ont été comparées à celles de leurs proies potentielles. Les résultats ont mis en évidence la présences des gobies, merlans, lançons, sprats, trisopterus sp., harengs et sardines comme proies potentielles. Le déplacement des marsouins du nord jusqu'au sud de la mer du Nord a été attribué à la baisse de l'abondance du lançon dans le nord, ainsi qu'à la ré-invasion du sud de la mer du Nord par la sardine, probablement suite au changement climatique. Enfin, cette étude confirme la nécessité d'utiliser une approche multi-analyses qui intègre des informations complémentaires à différentes échelles de temps pour étudier le régime alimentaire de ces prédateurs supérieurs<br>The North Sea is heavely impacted by human activities such as overfishing and pollution. Due to their position as top predators in the ocean, marine mammals are becoming increasingly affected by anthropogenic activities. The large-scale surveys SCANS in 1994 and SCANS II in 2005 that were held in the North Sea to estimate the abundance of small cetaceans highlighted a major shift in the distribution of harbour porpoises (Phocoena phocoena) from the northern parts of the North Sea to its eastern parts. Alongside, over the past few decades harbour porpoises stranding has increased in the southern North Sea particularly along the French and Belgian coastal waters. Since the contaminant exposure presents, among others, a potential threat to harbour porpoises inhabiting the North Sea, the first objective of the present study was to assess the contamination status of this species in the southern North Sea. On the other hand, the distribution and abundance of marine mammals is expected to follow the distribution of their main prey species. Hence, the second objective of this study was to investigate whether the changes in the distribution of porpoises in the southern North Sea may be a result of the changes in prey availability. Moreover, the third objective was to evaluate the interest of combining three methods to investigate the diet of harbour porpoises : stomach contents, stable isotopes (carbon and nitrogen) and fatty acids analyses. First, the contamination status was evaluated through the determination of two components of chemical contaminants (metals and persistent organic pollutants) in tissues of harbour porpoises stranded along the southern North Sea between 2006 to 2013. Several chemical contaminants presented higher concentrations in diseased animals compared to healthy animals. In addition, some metallic contaminants showed bioaccumulation with age. Comparison with previous study suggests that the population status of harbor porpoises in term of chemical concentration has been stable from 1994 to 2013. This work suggested that the increase in the number of stranded individuals is not related to the decline in the quality of the environment. Secondly, the shift in the abundance of harbour porpoises was evaluated and interpreted in the light of prey species abundance. Three techniques were used in order to determine the diet of porpoises. Results highlighted the presence of gobies, whiting, sandeel, sprat, trisopterus sp., herring and sardine as potential preys. The shift of the abundance of porpoises form the northern parts of the North Sea to its southern parts was attributed to the sandeel abundance decline in the northern parts of the North Sea along with the re-invasion of the southern North Sea by the sardine species, probably in response to climate change. Finally, the value of a multi-approach dietary analysis was evaluated. Besides overcoming the limitations of each method, combining different techniques that integrate diet over days and weeks allowed gaining more complete understanding of harbour porpoise's diet

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Wofford, Sarah Jane. "How does alteration of chemical information affect assessment in male and female crayfish, Orconectes rusticus?" Bowling Green State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu149011404454945.

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Guimaraes, Alexander Savio Ramos. "Quantitative 1H N.M.R. chemical shift imaging of neuronal content." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/28128.

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Benning, B. K. "Novel high water content hydrogels." Thesis, Aston University, 2000. http://publications.aston.ac.uk/9809/.

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The addition of N-isopropyl acrylamide to an acrylamide-based composition that had previously been designed to become a contact lens, produced materials that showed smart effects in that the water content showed dependence on the temperature of the hydrating solution. Such thermo-responsive materials have potential uses in drug delivery, ultrafiltration and cell culture surfaces. Proteoglycans in nature have an important role to play in structural support where a highly hydrophilic structure maintains lubricious surfaces. Certain functional groups that impart this hydrophilicity are present in certain sulphonate monomers, Bis(3-sulphopropyl ester) itaconate, dipotassium salt (SPI), 3-Sulphopropyl ester acrylate, potassium salt (SPA) and Sodium 2-(acrylamido)-2-methyl propane sulphonate (NaAMPS). These monomers were incorporated into a HEMA-based copolymer that had been designed initially as a contact lens and the resulting effects examined. Highly hydrophilic materials resulted that showed reduced protein deposition over the neutral core material. It is postulated that a sulphonate group would have a larger number of hydration shells around it than for example methacrylic acid, leading to more dynamic exchange and so reducing the adsorption of biological solutes. A cationic monomer was added to bring back the net anionic nature of the sulphonate hydrogels and the effects studied. Ionic interactions were found to cause a reduction in the water content of the resulting materials as the mobility of the network decreased, leading to stiffer but less extensible materials. The presence of a net dominant charge, whether negative or positive, appeared to act to reduce protein deposition, but increasing equivalence in the amount of both charges served to present a more 'neutral' surface and deposition subsequently increased. The grafting of hydrophilic hydrogel layers onto silicone elastomer was attempted and the results evaluated using dynamic contact angle measurements. Following plasma oxidation to reduce the surface energy barrier to aqueous grafting chemistry, it was found that the wettability of the modified elastomers could be significantly enhanced by such treatment. The SPA-grafted material in particular hinted at an osmotic drive for rehydration that may be exploited in biomaterials.

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Books on the topic "Chemical contents"

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W, Hornbeck James, and United States. Forest Service. Northeastern Research Station., eds. Database for chemical contents of streams on the White Mountain National Forest. U.S. Dept. of Agriculture, Forest Service, Northeastern Research Station, 2001.

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Gooch, Janet A. Proximate chemical composition and fatty acid contents of 37 finfish species of the southeastern United States. U.S. Dept. of Commerce, National Oceanic & Atmospheric Administration, National Marine Fisheries Service, Southeast Fisheries Center, Charleston Laboratory, 1989.

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Kabir, Ahammadul. Final report on rapid review of locally available arsenic field testing kits. APSU, 2006.

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B, Hale Malcolm, Galloway Sylvia B, and Southeast Fisheries Center (U.S.). Charleston Laboratory, eds. Proximate chemical composition and fatty acid contents of 37 finfish species of the southeastern United States: Janet A. Gooch, Malcolm B. Hale, Sylvia B. Galloway. U.S. Dept. of Commerce, National Oceanic & Atmospheric Administration, National Marine Fisheries Service, Southeast Fisheries Center, Charleston Laboratory, 1989.

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E, Sikorski Zdzisław, ed. Chemical & functional properties of food proteins. Technomic Pub. Co., 2001.

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Como, Patrizio Da, and Vincente Uber. Contaminated fish: Chemical residues and mercury. Nova Science Publisher's, 2012.

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Sauerbeck, Dieter. Funktionen, Güte und Belastbarkeit des Bodens aus agrikulturchemischer Sicht. Kohlhammer, 1985.

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Nigerian Society of Chemical Engineers. Conference. Chemical engineering and Nigerian content in the industrialisation of Nigeria. Nigerian Society of Chemical Engineers, 2006.

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Service, Chemical Abstracts. Patent information from Chemical Abstracts Service: Coverage and content. American Chemical Society, 1991.

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Mervyn, Richardson, ed. Chemistry, agriculture and the environment. ill., 1991.

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Book chapters on the topic "Chemical contents"

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"Contents." In Chemical Heroes. Duke University Press, 2020. http://dx.doi.org/10.1515/9781478010302-toc.

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"Contents." In Chemical Photocatalysis. De Gruyter, 2020. http://dx.doi.org/10.1515/9783110576764-toc.

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"Contents." In Chemical Technicians. De Gruyter, 2023. http://dx.doi.org/10.1515/9783111191492-toc.

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"Contents." In Chemical Reactivity. Elsevier, 2023. http://dx.doi.org/10.1016/b978-0-32-390257-1.00004-8.

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"Contents." In Chemical Reactivity. Elsevier, 2023. http://dx.doi.org/10.1016/b978-0-32-390259-5.00004-4.

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"Contents." In Chemical Bonding. De Gruyter, 2023. http://dx.doi.org/10.1515/9783111167213-toc.

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"Contents." In Chemical Synergies. De Gruyter, 2018. http://dx.doi.org/10.1515/9783110482065-202.

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"Contents." In Chemical Laboratory. De Gruyter, 2022. http://dx.doi.org/10.1515/9783110779127-toc.

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"Contents." In Chemical Kinetics. Elsevier, 2021. http://dx.doi.org/10.1016/b978-0-444-64039-0.00028-5.

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"Contents." In Chemical Alert! University of Texas Press, 1993. http://dx.doi.org/10.7560/746756-toc.

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Conference papers on the topic "Chemical contents"

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Yaguchi, Masatsugu, Tomoaki Hamaguchi, Kazuhiro Miki, Kyohei Nomura, and Nobuyoshi Komai. "Effects of Chemical Composition and Heat Treatment on Creep Properties of ASME Grade 91 Type Steel." In AM-EPRI 2024. ASM International, 2024. http://dx.doi.org/10.31399/asm.cp.am-epri-2024p1216.

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Abstract The effects of chemical composition and heat treatment on the creep properties of ASME Grade 91 type steel were experimentally investigated using materials whose chemical compositions and heat treatment conditions in the steel making process were completely controlled. Regarding chemical composition, only the Al, Cr, and Ni contents were systematically varied while keeping the contents of the other elements and heat treatment conditions constant. Regarding heat treatment, the normalizing and tempering temperatures were varied while keeping the contents of chemical components constant. The creep tests of materials were performed for approximately up to 50,000 h at 650°C. The creep strength of Grade 91 type steel decreased with increasing Al content under the test conditions of short-term to long-term range. On the other hand, the effect of Cr content on the creep life of Grade 91 type steel depended on the stress or time range, and the creep strength of the steel decreased at high Cr contents under test conditions of only the longterm range. No effect of Ni content on the creep life of the materials was observed in the test data obtained in this study. As creep tests are currently being conducted at 625°C and 60 MPa, which are conditions closer to the actual service conditions of main steam piping at ultra-super critical power plants, the creep deformation data at present indicate that the above trends hold true in the long-term range. Regarding the effect of heat treatment, the creep life of the materials tended to increase with increasing normalizing temperature or decreasing tempering temperature. The results obtained in this work indicate that within the scope of the material standards for Grade 91 type steel, the effect of chemical composition on creep life is greater than that of heat treatment.

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Tracy, Robert P., Joseph Colaruotolo, Anthony Misercola, and Barry R. Chuba. "Corrosion Performance and Economics of Electroless Nickel Coatings in Chemical Process Environments." In CORROSION 1986. NACE International, 1986. https://doi.org/10.5006/c1986-86022.

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Abstract An experimental study was conducted on electroless nickel plated 1010 carbon steel to determine the corrosion performance and economics in chemical process environments. Three electroless nickel coatings tested are represented by the alloy contents: 1-2, 6-8 and 10-12 weight percent phosphorus. The environments were common chemicals found in the specialty chemical production operations. Experimental conditions ranged in concentration and temperature to best simulate processing and chemical transporting conditions. The study demonstrates the feasibility based on corrosion performance and economics of electroless nickel coated low alloy steels as a substitute for higher cost alternate metallurgy for chemical processing applications.

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Keiser, James R., Gavin L. Warrington, Samuel A. Lewis, et al. "Corrosion and Chemical Characterization of Bio-Oils from Biomass with Varying Ash and Moisture Contents." In CORROSION 2021. AMPP, 2021. https://doi.org/10.5006/c2021-16726.

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ABSTRACT As part of the Feedstock Conversion Interface Consortium four samples of pine chips (all combinations of low and high moisture and ash content) were collected and processed for fast pyrolysis. The prepared biomass samples were liquefied at the National Renewable Energy Laboratory (NREL) using the fast pyrolysis process. Following some characterization of the bio-oils at NREL, the bio-oils were shipped to Oak Ridge National Laboratory (ORNL) for corrosion testing and further characterization. The content and composition of ash in each bio-oil was determined. Corrosion testing consisted of exposing selected metallic and elastomer samples for 1000 hr at 50°C and for longer times at room temperature as well as electrochemical impedance spectroscopy measurements to assess relative corrosivity of the bio-oils. Chemical characterization was conducted to identify the corrosive component of the bio-oils as well as to define the chemical differences among the oils. It was hypothesized that there could be a catalytic effect from the higher ash content in two of the biomass sources. Results of these characterization and corrosion studies will be reported.

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Chauveau, Eric, Diana Koschel, Nicole Bouvier, and Thiago J. Mesquita. "Influence of Metallurgy and Chemical Composition on the Sulphide Stress Cracking Resistance of Two Supermartensitics Stainless Steels." In CORROSION 2012. NACE International, 2012. https://doi.org/10.5006/c2012-01284.

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Abstract The sulphide stress cracking resistance of two supermartensitics UNS17400 and 1.4418(1) stainless steel bars was studied at different pH’s using the NACE method A. The study showed the very high sensitivity of this parameter on the Sulphide Stress Cracking (SSC) resistance. Concerning the metallurgy, the influence of two parameters on the SSC resistance of the 1.4418 is studied: the hardness and the content of residual austenite. The SSC resistance is discussed in a large range of mechanical properties from 650 up to about 1000 MPa. Bibliographic research showed that the content of residual austenite seems to influence the SSC resistance of martensitics in a positive way. We studied the cracking resistance of 1.4418 with different contents of residual austenite to verify this hypothesis. In order to study the electrochemical behaviour of the 1.4418 the corrosion potentials of the unloaded specimen were measured in the same media as those tested according the SSC method.

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Zhang, Mingyuan, Kaiyang Li, Xue Han, Yimin Zeng, and Chunbao Xu. "Corrosion Performance of Austenitic Stainless Steels under Hydrodeoxygenation Upgrading of Pyrolysis Oils Using Supercritical Ethanol." In CONFERENCE 2022. AMPP, 2022. https://doi.org/10.5006/c2022-18031.

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Abstract Crude pyrolysis bio-oils are recognized as a potential source to replace conventional fuels and chemicals. However, their high water content, viscosity and acidity significantly hinder industrial applications. Hydrodeoxygenation Upgrading (HDO) of pyrolysis bio-oil, can remarkably improve their quality and advanced the application of being as an alternative fuel or chemical. During the upgrading, the high contents of water and acids in of the crude bio-oil may introduce unwanted corrosion damage to the processing equipment. This paper investigated the corrosion performance of two candidate constructional steels (UNS S31603 and UNS S30400) under the HDO processes using supercritical ethanol solvent, NiMoW/Al2O3 catalyst and different hydrogen resources (hydrogen gas or formic acid) at 325 °C. The introduction of H2 gas or formic acid application of formic acid could effectively improve upgrading efficiency. The application of formic acid led to a less aggressive upgrading environment to the steels. UNS S31603 exhibited a better corrosion resistance under the catalytic HDO process compared to UNS S30400.

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Shargay, Cathleen A., Karly Moore, and Marty West. "Impact of Organic Acid on Materials Selection for Biofuels and Bio-Based Chemical Plants." In CORROSION 2014. NACE International, 2014. https://doi.org/10.5006/c2014-3729.

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Abstract With the recent increased development of advanced biofuel and bio-based chemical processing plants, materials selections need to be done for many novel plant designs. Organic acids are one of the corrosion-causing byproducts in these plants, along with aqueous carbonic acids, chlorides, etc. (depending on feedstocks). Since no direct past experiences with some unit designs were available, especially for streams with high organic acid contents, it was necessary to extrapolate from literature data and past “somewhat similar” operating experience to select candidate materials and set up future testing programs. The materials under review include austenitic and duplex stainless steels, and nickel based alloys. This paper summarizes a review done of the risk of organic acid corrosion, and gives examples of the initial materials selection decisions for various types of biofuels units.

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Masamura, Katsumi, Yasuto Inohara, and Yusuke Minami. "Effects of C and N on Corrosion Resistance of High Cr Alloys in CO2 and H2S Environments." In CORROSION 1998. NACE International, 1998. https://doi.org/10.5006/c1998-98116.

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Abstract In CO2 environments, corrosion rate of 12-13% Cr alloys depends on carbon and nitrogen contents, because C and N form carbides and nitrides reducing Cr content in matrix. From chemical analysis of extracted residuals, a new index Creff accounting N is proposed as following. Ceff=Cr−10(C+N) Good correlations were found between Creff and corrosion rate of high Cr alloys in CO2 environment. Results of polarization measurements indicate that C and N mainly control anodic behavior in high pH solutions. In NACE solution saturated with 1 atm H2S and low pH number, the precipitation of carbides and nitrides accelerated cathodic reaction resulting in high corrosion rate

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Galis, M. F. J., and G. C. Guntz. "Study of Metallurgical Parameters Influencing the Behavior of Line Pipes in H2S Medium." In CORROSION 1988. NACE International, 1988. https://doi.org/10.5006/c1988-88195.

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Abstract Various parameters affecting the H2S resistance of steel used to produce seamless Line Pipes were studied using lab-tests run on more than 250 industrial heats. It was verified that some chemical factors, such as sulfur, calcium and oxygen contents affected H2S resistance. More than those above particular parameters, a good balance also with a high knowledge of the steel maker is required. Those chemical aspects are more or less enhanced by the further metallurgical processes as heat treatments.

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Green, Matthew A., and Ruth Rodriguez. "Chemical Compatibility Testing of an Engineered Composite Repair System with 98% Sulfuric Acid at Various Temperature Levels." In CORROSION 2019. NACE International, 2019. https://doi.org/10.5006/c2019-13436.

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Abstract A research and development program was undertaken to create a composite material repair system which was compatible with high concentrations of sulfuric acid, up to 98%. The initial results of the program showed great promise in reaching a level of compatibility with the aggressive chemical and further testing and validation was required. The next level of testing was to include the effects of increasing temperature of the operating conditions on the compatibility of the system with 98% sulfuric acid. This testing program originated because of the demanding conditions found in most chemical processing facilities. Many requests for compatibility information between the pipe contents and the composite repair materials have been fielded from the industry, with sulfuric acid in high concentrations (up to 98%) being a routine chemical in question, thus the testing project was developed and completed. This paper will present the results obtained as well as insights gained throughout this research and development program in detail with regard to chemical compatibility with sulfuric acid at high concentrations and different temperature ranges evaluated.

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Ribeiro, Carlos A. A., Thais B. Fagundes, Gaspar Darin Filho, Patricia H. L. S. Matai, and Jean V. Ferrari. "Study of Corrosion of ABNT/AISI 1020 Steel in Surfactant Waterflooding Scenario." In LatinCORR 2023. AMPP, 2023. https://doi.org/10.5006/lac23-20537.

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Abstract Surfactant flooding can be one of the chemical-enhanced oil recovery methodologies (CEOR) applied during well production over time by reducing the oil-water interfacial tension and changing the rock's wettability. Surfactants, being surface-active agents, have also been studied with the function of film-forming corrosion inhibitors; however, at low concentration approaches, usually up to the critical micelle concentrations (CMC), around 1 mg/L to 100 mg/L. This work may contribute to studies about the anti-corrosive performance of such chemicals in waterflooding scenarios, which can inject contents up to 30,000 mg/L. Thus, this work aims to study the influence of a cationic surfactant, the cetyltrimethylammonium bromide (CTAB), and an anionic, the sodium dodecyl sulfate (DDS), on the corrosion of ABNT/AISI 1020 steel in NaCl 3% (w/w) static medium and pH 4 (adjusted with HCl aqueous solution).

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Reports on the topic "Chemical contents"

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Hornbeck, James W., Michelle M. Alexander, Christopher Eagar, Joan Y. Carlson, and Robert B. Smith. Database for chemical contents of streams on the White Mountain National Forest. U.S. Department of Agriculture, Forest Service, Northeastern Research Station, 2001. http://dx.doi.org/10.2737/ne-gtr-282.

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Bruce, Berg, and Agrawald. L52304 Development of Criteria-Guidelines for Welding Onto In-Service Chemical Pipelines. Pipeline Research Council International, Inc. (PRCI), 2009. http://dx.doi.org/10.55274/r0010678.

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Welding onto in-service pipelines and piping systems allows cost-effective installation of branchconnections (hot taps) and repair sleeves. Beyond the normal in-service welding concerns ofburnthrough and hydrogen cracking, there are often additional concerns when welding ontopipelines and piping systems in chemical service. For example, some products can undergochemical changes when exposed to the heat from an in-service weld. In spite of these concerns,some companies routinely weld on lines in chemical and other potentially hazardous service,although limitations and special precautions are often specified. Examples include wallthickness limitations below which in-service welding is not permitted and the use of weldingprocedures that limit heat input. The objective of this project was to review the concerns forwelding on in-service pipelines in chemical service, the techniques that have been used in thepast to address these concerns, and to develop criteria that will allow this type of welding to becarried out safely. Criteria for in-service welding were developed for a wide range of chemicals that were identified as being of interest. The format for these criteria is similar to material safety data sheets (MSDSs). Many of the potential concerns that were identified can be controlled by limiting the inside surface temperature. Factors that affect inside surface temperature include: (1) pipe wall thickness, (2) the introduction of heat into the pipe wall by the welding process, and (3) the removal of heat by the contents. For many of the concerns that were identified, if protection from burnthrough using the inside surface temperature approach is practiced, protection from these other concerns is also accomplished. The ability to accurately control heat input levels is an important aspect of being able to weld safely onto in-service pipelines, particularly when inside surface temperature needs to be limited. Methods for controlling heat input levels in the field were reviewed and detailed guidance was developed. The benefits of using small-diameter electrodes (lower current levels), which allows the attachment of a hot tap fittings at relatively low heat input levels, were identified. Techniques to address other concerns that are not inside surface temperature related were also identified.

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Tennis, Paul, Michael Thomas, W. Jason Weiss, Eric Giannini, and James Farny. State-of-the-Art Report on Use of Limestone in Cements at Levels of up to 15%. Portland Cement Association, 2024. https://doi.org/10.70909/pca.2024.sn3128.03.

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This document is to serve as background technical information for engineers, specifiers, and other concrete technologists on use of portland-limestone cements with limestone contents in amounts up to 15% (focusing on amounts between 5% and 15%) and the use of these cements in concrete. Standard requirements for portland-limestone cements in the U.S. are found in ASTM C595 and AASHTO M 240, Standard Specification for Blended Hydraulic Cements. Environmental benefits are discussed as well as a history of use of cements with limestone, including a selection of case studies of projects in the U.S. and Canada. The chemical and physical effects of limestone on fresh and hardened properties of concrete are emphasized.

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Clement, Michael, Sage Broderick, and Marty Garton. Toxic Industrial Chemical / Material Intelligence Tool (TICMINT) user guide. Engineer Research and Development Center (U.S.), 2023. http://dx.doi.org/10.21079/11681/47924.

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The Toxic Industrial Chemical / Material Intelligence Tool (TICMINT) is a web application that provides critical chemical and toxicological information to users quickly and efficiently for the purpose of enacting safe maneuvers in areas of operations. It provides an in-depth look at the makeup, properties, and hazardous effects of nearly 400 toxic chemicals of interest. It also provides background on the chemical makeup of a bevy of building materials, enabling soldiers in areas of operation to determine the toxicological risks associated with the combustion of those materials in their environment. This document’s purpose is to demonstrate the functionality of the TICMINT web application and provide instructional material for those managing its content.

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Pisutha-Arnond, Visut, Sirichai Sunmanee, and Sudham Yaemniyom. A report on copper skarn deposit at Phu Lon, Amphoe Sang Khom Changwat Nong Khai. Chulalongkorn University, 1988. https://doi.org/10.58837/chula.res.1988.18.

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Based on the geological and petrographical studies and chemical analysis of drill-core and outcrop samples, the geology and mineralization at the Phu Lon area are revealed. The Phu Lon prospect is a Cu-Fe-Au-Ag skarn deposit of porphyry-related type. The copper- and iron-rich zones are hosted predominantly in the garnet-pyroxene skarn that is developed metasomatically at the contact between the diorite-monzodiorite intrusions and a marble with minor calcsilicate unit. The main stage of iron mineralization probably took place during the prograde garnet-pyroxene skarn formation and was genetically related to the diorite-monzodiorite. The ore minerals include magnetite, minor chalcopyrite and pyrite, and occur in the form of massive patches or bands in the skarn. Quartz monzonite porphyry – monzonite dikes/stocks post-date the diorite-monzodiorite and the garnet-pyroxene skarn. Extensive alterations overprinting on both intrusive and volcanic rocks (i.e., potassic, phyllic and propylitic) are probably related to the cooling of quartz monzonite porphyry-monzonite. Close accompanying the alterations, the main stage of copper mineralization and retrograde skarn alteration of epidote-chlorite-calcite commenced. The mineralization occurs in the from of chalcopyrite-pyrite-quartz veins/veinlet networks predominantly in the skarn unit. Other associated minerals include magnetile, hematite and molybdenite. Trace amounts of gold and silver are chemically detected and probably associated with the copper mineralization. Their contents are comparable to those of the similar copper-gold deposit class. It is attractive for persuading further exploration.

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Führ, Martin, Julian Schenten, and Silke Kleihauer. Integrating "Green Chemistry" into the Regulatory Framework of European Chemicals Policy. Sonderforschungsgruppe Institutionenanalyse, 2019. http://dx.doi.org/10.46850/sofia.9783941627727.

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20 years ago a concept of “Green Chemistry” was formulated by Paul Anastas and John Warner, aiming at an ambitious agenda to “green” chemical products and processes. Today the concept, laid down in a set of 12 principles, has found support in various arenas. This diffusion was supported by enhancements of the legislative framework; not only in the European Union. Nevertheless industry actors – whilst generally supporting the idea – still see “cost and perception remain barriers to green chemistry uptake”. Thus, the questions arise how additional incentives as well as measures to address the barriers and impediments can be provided. An analysis addressing these questions has to take into account the institutional context for the relevant actors involved in the issue. And it has to reflect the problem perception of the different stakeholders. The supply chain into which the chemicals are distributed are of pivotal importance since they create the demand pull for chemicals designed in accordance with the “Green Chemistry Principles”. Consequently, the scope of this study includes all stages in a chemical’s life-cycle, including the process of designing and producing the final products to which chemical substances contribute. For each stage the most relevant legislative acts, together establishing the regulatory framework of the “chemicals policy” in the EU are analysed. In a nutshell the main elements of the study can be summarized as follows: Green Chemistry (GC) is the utilisation of a set of principles that reduces or eliminates the use or generation of hazardous substances in the design, manufacture and application of chemical products. Besides, reaction efficiency, including energy efficiency, and the use of renewable resources are other motives of Green Chemistry. Putting the GC concept in a broader market context, however, it can only prevail if in the perception of the relevant actors it is linked to tangible business cases. Therefore, the study analyses the product context in which chemistry is to be applied, as well as the substance’s entire life-cycle – in other words, the six stages in product innovation processes): 1. Substance design, 2. Production process, 3. Interaction in the supply chain, 4. Product design, 5. Use phase and 6. After use phase of the product (towards a “circular economy”). The report presents an overview to what extent the existing framework, i.e. legislation and the wider institutional context along the six stages, is setting incentives for actors to adequately address problematic substances and their potential impacts, including the learning processes intended to invoke creativity of various actors to solve challenges posed by these substances. In this respect, measured against the GC and Learning Process assessment criteria, the study identified shortcomings (“delta”) at each stage of product innovation. Some criteria are covered by the regulatory framework and to a relevant extent implemented by the actors. With respect to those criteria, there is thus no priority need for further action. Other criteria are only to a certain degree covered by the regulatory framework, due to various and often interlinked reasons. For those criteria, entry points for options to strengthen or further nuance coverage of the respective principle already exist. Most relevant are the deltas with regard to those instruments that influence the design phase; both for the chemical substance as such and for the end-product containing the substance. Due to the multi-tier supply chains, provisions fostering information, communication and cooperation of the various actors are crucial to underpin the learning processes towards the GCP. The policy options aim to tackle these shortcomings in the context of the respective stage in order to support those actors who are willing to change their attitude and their business decisions towards GC. The findings are in general coherence with the strategies to foster GC identified by the Green Chemistry & Commerce Council.

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Ley, M., Zane Lloyd, Shinhyu Kang, and Dan Cook. Concrete Pavement Mixtures with High Supplementary Cementitious Materials Content: Volume 3. Illinois Center for Transportation, 2021. http://dx.doi.org/10.36501/0197-9191/21-032.

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Fly ash is a by-product of coal combustion, made up of particles that are collected through various methods. This by-product has been used successfully as a partial Portland cement replacement in concrete, but the performance predictions of fly ash in concrete have been difficult to predict, especially at high fly ash replacement rates. This study focuses on comparing the performance of concrete with a variety of fly ash mixtures as well as the particle distribution and chemical makeup of fly ash. The slump, unit weight, compressive strength, and isothermal calorimetry tests were used to measure the performance of concrete at 0%, 20%, and 40% fly ash replacement levels. The particle distribution of fly ash was measured with an automated scanning electron microscope. Additionally, the major and minor oxides from the chemical makeup of fly ash were measured for each mixture and inputted into a table. The particle distribution and chemical makeup of fly ash were compared to the performance of slump, unit weight, compressive strength, isothermal calorimetry, and surface electrical resistivity.

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Beckett-Brown, C. E., A. M. McDonald, and M. B. McClenaghan. Discovering a porphyry deposit using tourmaline: a case study from Yukon. Natural Resources Canada/CMSS/Information Management, 2023. http://dx.doi.org/10.4095/331349.

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As the exploration for porphyry Cu-Au-Mo deposits has become increasingly challenging, the development of more effective techniques directed at detecting buried deposits has become critical. One methodology is to focus on key minerals, one of which is tourmaline, a robust, ubiquitous mineral in most mineralized porphyry systems. Overall, a combination of physical and chemical characteristics including 1) macro-color, 2) morphology, 3) inclusion populations, and 4) trace-element compositions are useful in discriminating between porphyry- versus non-porphyry-derived (or related) tourmaline in surficial sediments (Beckett-Brown 2022). These features are applied to tourmaline obtained from stream sediment samples (n = 22) from 16 streams derived from the unglaciated terrain proximal to the Casino calc-alkaline porphyry Cu-Au-Mo deposit (Yukon Territory, Canada). The obtained tourmaline occurs as two distinct morphologies: 1) individual blocky to prismatic sub- to euhedral grains (Type 1), 2) aggregates of radiating prismatic to acicular sub- to euhedral grains (Type 2). Type 1 grains display trace-element contents that reflect mixed origins including a mineralized porphyry origin as well metamorphic and pegmatitic (background) environments. Type 2 grains almost exclusively exhibit porphyry-derived trace-element chemistries (i.e., high Sr/Pb ~150 avg. and relatively low Zn/Cu ~2.5 avg. values). In Canadian Creek, that directly drains from the Casino deposit, samples closest to the deposit contain &amp;gt;70% porphyry-derived tourmaline, while other streams in the region from unprospective drainage basins contain no porphyry-derived tourmaline. At the most distal sample site in Canadian Creek, ~20 km downstream from Casino, nearly 30% of the recovered tourmaline in the stream sediments is porphyry-related. This method has potential to be a strong indicator of prospectivity and applicable for exploration for porphyry Cu-Au-Mo systems in both unglaciated and glaciated terrains.

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Yam, C. G., R. Armstrong, M. L. Koszykowski, J. Y. Chen, and M. N. Bui-Pham. Increasing the chemical content of turbulent flame models through the use of parallel computing. Office of Scientific and Technical Information (OSTI), 1996. http://dx.doi.org/10.2172/412324.

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Mueller, C., S. J. Piercey, M. G. Babechuk, and D. Copeland. Stratigraphy and lithogeochemistry of the Goldenville horizon and associated rocks, Baie Verte Peninsula, Newfoundland. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328990.

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The Goldenville horizon in the Baie Verte Peninsula is an important stratigraphic horizon that hosts primary (Cambrian to Ordovician) exhalative magnetite and pyrite and was a chemical trap for younger (Silurian to Devonian) orogenic gold mineralization. The horizon is overlain by basaltic flows and volcaniclastic rocks, is intercalated with variably coloured argillites and cherts, and underlain by mafic volcaniclastic rocks; the entire stratigraphy is cut by younger fine-grained mafic dykes and coarser gabbro. Lithogeochemical signatures of the Goldenville horizon allow it to be divided into high-Fe iron formation (HIF; &amp;gt;50% Fe2O3), low-Fe iron formation (LIF; 15-50% Fe2O3), and argillite with iron minerals (AIF; &amp;lt;15% Fe2O3). These variably Fe-rich rocks have Fe-Ti-Mn-Al systematics consistent with element derivation from varying mineral contributions from hydrothermal venting and ambient detrital sedimentation. Post-Archean Australian Shale (PAAS)-normalized rare earth element (REE) signatures for the HIF samples have negative Ce anomalies and patterns similar to modern hydrothermal sediment deposited under oxygenated ocean conditions. The PAAS-normalized REE signatures of LIF samples have positive Ce anomalies, similar to hydrothermal sediment deposited under anoxic to sub-oxic conditions. The paradoxical Ce behaviour is potentially explained by the Mn geochemistry of the LIF samples. The LIF have elevated MnO contents (2.0-7.5 weight %), suggesting that Mn from hydrothermal fluids was oxidized in an oxygenated water column during hydrothermal venting, Mn-oxides then scavenged Ce from seawater, and these Mn-oxides were subsequently deposited in the hydrothermal sediment. The Mn-rich LIF samples with positive Ce anomalies are intercalated with HIF with negative Ce anomalies, both regionally and on a metre scale within drill holes. Thus, the LIF positive Ce anomaly signature may record extended and particle-specific scavenging rather than sub-oxic/redox-stratified marine conditions. Collectively, results suggest that the Cambro-Ordovician Taconic seaway along the Laurentian margin may have been completely or near-completely oxygenated at the time of Goldenville horizon deposition.

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