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1
Nordberg, Anna. "Priority setting strategies for regulatory testing of industrial chemicals". Licentiate thesis, Stockholm : Philosophy and the History of Technology, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4554.
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Dingle, Gwendolyn O. "Dual-use technology and sustainment of the chemical industrial base". Thesis, Monterey, California. Naval Postgraduate School, 1995. http://hdl.handle.net/10945/7501.
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The changing defense acquisition process and the declining defense budget require alternative methods for sustaining unique sectors of the defense technology industrial base (DTIB) such as the chemical sector. One method is the dual-use of the technology
3
Wilkinson, Sam K. "Reaction kinetics in formulated industrial catalysts". Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/5113/.
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In heterogeneous catalysis, a fundamental understanding of the necessary physico-chemical requirements for a catalyst formulation is essential to its success. Understanding of reaction kinetics via modelling can demonstrate how catalysts work, providing functional information around surface active sites and reaction mechanism. This tool, combined with well-designed laboratory experiments to test a catalyst under steady and/or non-steady state conditions, can provide insight into the links between catalyst formulation and reaction performance. The aim of this project is to develop novel strategies and methods in these areas utilising a range of Johnson Matthey catalysts and reaction systems. This thesis places significant focus on obtaining mechanistically and statistically sound kinetic models with reliable model parameter estimates. Methods for this are developed using a batch liquid phase hydrogenation system using a Pt/TiO2 catalyst. Subsequently, non-steady state analysis of catalyst formulations has been explored. This includes the initial transient behaviour of a fresh vanadium phosphorus oxide selective oxidation catalyst under reaction conditions which allowed understanding of the evolution of distinct active site populations on the catalyst surface. A subsequent study of copper-based methanol synthesis catalysts explored the impact of gas phase conditions on the catalyst state. A mixture of steady-state testing and transient response experiments (i.e. via an imposed change in gas phase conditions over the catalyst) provided new insights into the evolution of active site populations and populations of surface species on the catalyst surface. Overall, the reaction kinetics studies demonstrated across this thesis demonstrate not only a series of methods to understand catalyst behaviour in depth but also to understand the key functional requirements for an effective industrial catalyst.
4
Kanga, Yao. "Controlled release of Isothiazoline biocides from industrial minerals". Thesis, University of Birmingham, 2011. http://etheses.bham.ac.uk//id/eprint/1594/.
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This project investigated how various minerals of different surface areas and morphologies can be used to adsorb isothiazoline biocides for controlled-release and antimicrobial purposes. The absorption of the biocides on the mineral powders was achieved by way of using a bench high shear mill (dry process), or combining them to hydrated minerals (wet process). The characterisation of the minerals was achieved by XRF (chemical composition), XRD (crystal composition), SEM (morphology), B.E.T nitrogen (surface area), and Light Scattering (particle size distribution). HPLC was used to determine the concentration of the biocide in solution, and the Flow Microcalorimeter used to measure the bond strength between the biocide molecules and the minerals. The minerals were added to an exterior paint made according to an Imerys in-house formulation. Various modifications of this initial coating formulation were made in order to compare the biocide 2-Octyl-4-isothiazolin-3-one (OIT) release profiles from impregnated and non-impregnated minerals. Montmorillonite clay was the best performing mineral in all experiments (adsorption and desorption both from the minerals and paints films, strength of bond analysis, and bioassay). All other minerals tested carried the biocide with varying degree of success. Optical and mechanical tests performed on paint films containing various minerals suggested there were no significant differences between the films. Rheology tests demonstrated that newly developed formulations were easy to apply to a surface.
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Clark, Ian Paul. "Treatment studies on a xenobiotic containing industrial effluent". Thesis, University of Birmingham, 1990. http://etheses.bham.ac.uk//id/eprint/1397/.
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Sidwall, Shaun. "The industrial application of a multiple technique paper dryer simulation /". Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=21325.
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Drying Doctor, a multiple technique simulator of the paper drying process, has been developed at the Pulp and Paper Research Centre, McGill University. This thesis examines the different approaches to the modeling of this process, provides a rigorous validation of the simulation program and demonstrates its utility with four containerboard machines of Norampac Inc.Several features differentiate this simulator from others. When heavy grades of paper are produced or when high intensity drying processes are used even with thin sheets, substantial thickness direction gradients of moisture content and temperature develop across the sheet, demonstrating the necessity of a fully microscale model such as employed by Drying Doctor.
Using industrial and laboratory data for a variety of paper grades and drying processes, 31 uncalibrated simulations for machine speed showed a standard deviation of only 3.4% from known speeds. Through simulation of modified operating conditions such as steam pressure, spoiler bars, pocket air conditions and addition of the high intensity drying process, Yankee air impingement dryers, substantial production rate increases for the industrial partner's papermachines through use of the Drying Doctor simulator were shown possible.
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Pearmain, David. "Electron microscopy characterisation of size-selected Pd clusters and industrial Pd catalysts". Thesis, University of Birmingham, 2011. http://etheses.bham.ac.uk//id/eprint/1509/.
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This thesis presents an investigation into the morphology of palladium (Pd) size selected clusters and industrial Pd catalysts using high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) technique. The driving force of this work is to establish reliable and efficient methods for the structural characterisation of nanostructures. The characterisation of nanostructures is essential to our fundamental understanding of cluster use within applications, such as catalysis. The complexity of the morphology of industrial catalysts presents a significant challenge to rapid screening techniques. This thesis presents an efficient method which uses size selected clusters as mass standards in STEM based mass spectrometry. Size selected clusters were created using a radio frequency magnetron sputtering cluster beam source in conjunction with a lateral time of ight mass selector, Pd clusters were soft-landed onto amorphous carbon grids between the size range of N = 454 to 10,000 (\(\pm\)4%), with a deposition energy of 500 eV. The quantitative image analysis allows one to gain insight into each catalytic Pd particle and, in combination with two-dimensional diameter measurements, evaluate the three dimensional morphology of the particles. The use of the cluster source has also allowed investigation into the formation mechanisms of nanostructures, finding specific size-dependant morphological features for Pd clusters. Elongation of Pd clusters has been observed for cluster sizes of \(\geq\) 2000 atoms, as well as the onset of voids within the cluster structure for sizes \(\geq\) 2622. HAADF-STEM analysis has proved to be an invaluable tool in the determination of cluster size, independent of morphology, as well as enabling specific structural features within clusters to be revealed. An investigation into the atomic structure of supported Pd\(_{887}\) clusters is also presented. Specific structural motifs are identified using aberration corrected STEM within the sample range via direct comparison with simulated HAADF-STEM images of structures simulated using global minimum techniques.
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Callaghan, Fergal James. "Co-digestion of agricultural and industrial wastes". Thesis, University of Birmingham, 1998. http://etheses.bham.ac.uk//id/eprint/3601/.
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Anaerobic digestion technology has not gained widespread acceptance on UK farms due mainly to the long return on investment periods involved. It has been suggested that co-digestion of agricultural and industrial wastes may enhance the economic viability of such installations. Batch and continuous digestion of cattle slurry and organic industrial wastes was carried out in specially constructed pilot plant digesters, to determine optimum mixtures of waste and digester loading rates. A total of 10 different wastes were tested, on a batch digestion basis, for their potential to co-digest with cattle slurry. Of these, 3 were chosen for continuous pilot plant trials, due to either a need to provide a disposal route for the waste, or positive effects of the waste on methane productivity. Chicken manure was found to slightly enhance methane productivity, but ammonia inhibition of methanogenic bacteria was noted over time. The organic fraction of municipal household waste (OFMSW) significantly enhanced digester methane productivity, while fish offal (FO) slightly enhanced methane productivity when added to the digester in small quantities, but quickly caused digester failure when added in larger amounts. An economic model of a digestion facility was developed and used to show the financial benefits of co-digestion.
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Tripathi, Nagendra. "A Study on the Population and Chemical Development of Non-Metallic Inclusions in the Tool-Steel Making Process". Doctoral thesis, KTH, Materials Science and Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3827.
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The present work was to study the population and chemicalcharacterization of the inclusions at different steps of thetool steel making process based on industrial trialexperiments. The inclusion populations were found to increasewith ladle age (number of heats ladle being used) beforealuminium deoxidation and before casting. A substantialincrease in inclusion population was noticed after a certainladle age. The analyses of the steel samples from thesolidified ingot revealed a non-uniform distribution ofinclusions. The inclusion populations in the final productswere also found to increase with the ladle age.
Totally four types of inclusions, viz. Type-1 (MgO), Type-2(an oxide solution), Type-3 (spinel), and Type-4 (spinel in thecenter surrounded by the oxide solution of Type-2) wereobserved before deoxidation. Thermodynamic calculation revealedthat the Type-2 and Type-4 inclusions were generated by thereactions between EAF slag and ladle glaze. Three types ofinclusions were found before casting, viz. Type-6 (spinel inthe center surrounded by the oxide solution of Type-7), Type-7(oxide solution with low contents of MgO and SiO2), and Type-8 (small MgO islands embedded in anoxide solution). Inclusions of both Type-6 and Type-7 were theproducts of the reaction between inclusions of Type-3 and theliquid metal. On the other hand, the occurrence of pieces ofMgO having sharp edges in the oxide solution suggested that theType-8 inclusions were generated by the ladle glaze. In thesteel samples during mould fillings, totally three types ofinclusions namely, Type-6, Type-7, and Type-9 (alumina basedinclusions) were found. The Type-9 inclusions were originatedfrom the erosion of the nozzles and the closing gates duringthe mould filling. The steel samples after casting were foundto contain inclusions of Type-6, Type-7, Type-9, Type-10(alumina-silicate oxide solution), and Type-11 (spinel phasewith calcium sulphide). The types of inclusions were found tovary with the position in the ingot. In the final productsType-6, Type-7, and Type-11 inclusions were found. While almostall the inclusions in the final products were originated in theladle before casting, sulphur was detected in all types ofinclusions. The increase in the sulphur activity of the steelmelt during casting was the cause of the formation ofoxide-sulphide and calcium sulphide phases in the inclusionsdetected after casting and in the final products.
A preliminary examination on the possibility of inclusionseparation by bubble floatation using cold models was alsocarried out. Deionised water and silicon oil were used as thebulk phase. Charcoal particles of different size ranges wereemployed as the dispersed phase. The examination of thecharcoal-water-gas system indicated that the positivefloatation coefficient was not a sufficient condition for theinclusion separation. The experimental results were found to bein contradiction with the prediction of a typical model thatconsiders interfacial energies. The omitting of the drag forcewas believed to be the reason causing the failure of the modelprediction in the charcoal-water-gas system. The failure of themodel prediction suggested a need of a new model taking intoaccount interfacial energies, drag force, buoyancy force andgravity force.
Key words:non-metallic inclusions, ladle metallurgy,ladle glaze, inclusion population, ladle age, ingot casting,interfacial tension, inclusion separation
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Kings, Iain Nicholas. "Supercritical water oxidation as a technology for the treatment of model and industrial wastewaters : reaction kinetics and reactor configurations". Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4448/.
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This work investigates the advantages of a multi-stage supercritical water oxidation (SCWO) reactor over a single-stage configuration in treating dimethylformamide (DMF), a model compound representing nitro-organic wastewaters. Single-stage SCWO of complex wastewaters was also investigated. A PFR rig was designed and constructed to investigate reactor temperature, initial DMF concentration, stoichiometric ratio, residence time and oxidant distribution effects on component yields. Reaction temperature was the critical variable for treatability; T>500\(^0\)C caused near-complete DMF/TOC removal at relatively short residence times (approx. 6 s). DMF SCWO displayed Arrhenius-type kinetics, and the DMF (1) and O\(_2\) (0.36) reaction orders, activation energy (140 kJ mol\(^-\)\(^1\)) and pre-exponential factor (1x10\(^1\)\(^2\) M\(^0\)\(^.\)\(^3\)\(^6\) s\(^-\)\(^1\)) were evaluated. Certain injection configurations resulted in higher TOC removals than single-stage, particularly when the second injection occurred at 0.5L and delivered 50 – 67% of the oxidant, although ammonia yield exceeded those in single-stage SCWO at these points. Single-stage SCWO outperformed a small number of configurations. T>500\(^0\)C was shown to be suitable to treat complex wastes. Complete conversion of TOC to products likely occurs within 10\(^2\) s. It was seen that TOC value alone may not be a suitable input when attempting to determine treatability in SCWO and that composition must also be considered.
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Kisling, Eric Lance. "An implementation of information technological change a socio-technical systems methodology perspective at the Black Chemical Company /". [Bloomington, Ind.] : Indiana University, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3215190.
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Thesis (Ph.D.)--Indiana University, Dept. of Instructional Systems Technology, 2006.Source: Dissertation Abstracts International, Volume: 67-04, Section: A, page: 1301. Adviser: Thomas M. Schwen. "Title from dissertation home page (viewed May 14, 2007)."
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Sherazi, Aisha. "Multiple hormonal activities of industrial chemicals". Thesis, Brunel University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324553.
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Mais, Anton. "Utilization of sweet potato starch, flour and fibre in bread and biscuits : physico-chemical and nutritional characteristics : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Technology in Food Technology, Massey University". Massey University, 2008. http://hdl.handle.net/10179/921.
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Sweet-potato contains a limited amount of protein, although rich in dietary fibre content and carbohydrate, so a successful combination with wheat flour for bread and biscuit production would be nutritionally advantageous. In particular, the role of these ingredients in relating to acceptability of breads and biscuit with higher percentage of sweet potato starch, flour in wheat flour. In this study, starch, flour and residue fibre of three sweet-potato varieties (red, orange and white -types) were studied. The 5 -10% combination levels for biscuit-making were found to be acceptable, without affecting the quality of the biscuit (combination of texture and biscuit size). In bread, bread containing 15% red and white replacement starches and orange replacement flour was found to be acceptable level, without affecting the quality of the bread, in an attempt to replace wheat at higher per cent level. The physicochemical study was complemented with a nutritional study to determine beneficial effects of food rich in dietary fibre and starches, in the context of improving diet related problems. RVA results showed sweet-potato ingredients affected differently the pasting temperature, peak viscosity and final viscosity of the normal wheat flour (p<0.05). Fibre inclusion showed large reduction in viscosity and swelling of sweet potato starch. Biscuits and breads containing sweet-potato starch and flour are low in amylose, and digest slowly because of lowly oriented and ‘crystalline’ areas within the granules enable to swell or to ungelatinised starch granules, whereas wheat control biscuit was able to gelatinised starch and exerted a greater effect upon digestibility. There are many other factors that need to be considered when analysing the in vitro starch digestibility such including amylose content, amylopectin structure and presence of fibre and gelatinising. Sweet-potato starch, flour and fibre addition show least effect on bread texture and size and starch, flour and fibre replacement. However, in in vitro starch digestibility test higher values RSS was recorded for starch addition followed by flour addition.
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Zhang, Jin. "In silico Identification of Thyroid Disrupting Chemicals : among industrial chemicals and household dust contaminants". Doctoral thesis, Umeå universitet, Kemiska institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-125631.
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Thyroid disruptions by xenobiotics have been associated with a broad spectrum of severe adverse human health effects, such as impaired brain development and metabolic syndrome. Ingestion of indoor dust and contact with industrial chemicals are two significant human exposure routes of thyroid hormone disrupting chemicals (THDCs), raising serious concerns for human health. However, it is a laborious and costly process to identify THDCs using conventional experimental methods, due to the number of chemicals in commerce and the varieties of potential disruption mechanisms. In this thesis, we are aimed at in silico identification of novel THDCs targeting transthyretin (TTR) and thyroid hormone receptor (THR) among dust contaminants and commonly used industrial chemicals. In vitro assays were used to validate the in silico prediction results. Co-crystallization and molecular dynamics (MD) simulations were applied to reveal binding modes of THDCs at the studied biological targets and to explain their intermolecular recognition. The main findings presented in this thesis are: 1. Over 144 environmental pollutants have been confirmed as TTR-binders in vitro and these cover a wide range of environmental pollutants and show distinct chemical profiles including a large group of halogenated aromatic compounds and a second group of per- and polyfluoroalkyl substances. (Paper I) 2. In total 485 organic contaminants have been reported to be detected in household dust. The developed QSAR classification model predicted 7.6% of these dust contaminants and 53.1% of their metabolites as potential TTR-binders, which emphasizes the importance of metabolic bioactivation. After in vitro validation, four novel TTR binders with IC50 ≤ 10 µM were identified, i.e. perfluoroheptanesulfonic acid, 2,4,2',4'-tetrahydroxybenzophenone (BP2), 2,4,5-trichlorophenoxyacetic acid, and 3,5,6-trichloro-2-pyridinol. (Paper II) 3. The development of a robust structure-based virtual screening (VS) protocol resulted in the prediction of 31 dust contaminants as potential binders to THRβ1 including musk compounds, PFASs, and bisphenol A derivatives. The in vitro experiments confirmed four compounds as weak binders to THRβ1, i.e. 2,4,5-trichlorophenoxyacetic acid, bisphenol A (3-chloro-2-hydroxypropyl) (2,3-dihydroxypropyl) ether, 2,4,2',4'-tetrahydroxybenzophenone, and 2,4-dichlorophenoxyacetic acid. (Paper III) 4. We revealed the binding conformations of perfluorooctanesulfonic acid, perfluorooctanoic acid, and BP2 in the thyroxine binding sites (TBSs) of TTR by co-crystallizing TTR with the three compounds. A VS protocol was developed based on the TTR complex structures that predicted 192 industrial chemicals as potential binders to TTR. Seven novel TTR binders were confirmed by in vitro experiments including clonixin, 2,6-dinitro-p-cresol (DNPC), triclopyr, fluroxypyr, bisphenol S, picloram, and mesotrione. We further co-crystallized TTR with PBS, clonixin, DNPC, and triclopyr, and their complex structures showed that the compounds bind in the TBSs as proposed by the VS protocol. In summary, 13 indoor dust contaminants and industrial chemicals were identified as THDCs using a combination of in silico and in vitro approaches. To the best of our knowledge, none of these compounds has previously been reported to bind to TTR or THR. The identifications of these THDCs improve our understanding on the structure-activity relationships of THDCs. The crystal structures of TTR-THDC complexes and the information on THDC-Target intermolecular interactions provide a better understanding on the mechanism-of-actions behind thyroid disruption. The dataset compiled and in silico methods developed serve as a basis for identification of more diverse THDCs in the future and a tool for guiding de novo design of safer replacements.
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de, Albuquerque Fragoso Danielle Munick. "Lignin conversion to fine chemicals". Thesis, University of Glasgow, 2018. http://theses.gla.ac.uk/30847/.
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The large availability of Kraft lignin as an industrial by-product and its polyaromatic characteristic, is ideal to consider the potential for recycling it into fine chemicals. To depolymerise lignin, solvolysis and hydrogenolysis experiments were performed. This research considered whether the low yields of products (fine chemicals) were related to the low content of β-O-4 bonds or if it was also associated to the dissolution of lignin in the solvent solution employed in the reactions. The type of solvents chosen to check the dissolution effect were those with low cost and were more sustainable than traditional solvents. Water, ethanol, isopropanol (IPA) and acetone were used. The water mixtures were applied in the tests in various proportions (25:75, 50:50, 75:25 solvent/water v:v). Due to their ability to break C-C and C-O bonds in lignin model compounds [1][2], the efficiency of platinum and rhodium in these reactions supported on alumina was also studied. It was found that the non-catalysed (solvolysis) and catalysed reactions showed different selectivities but similar overall yields ~ 10 % wt of monomeric phenols. The difficulty in increasing yields was mainly associated with the highly condensed character of Kraft lignin and re-polymerisation issues. To achieve an understanding of Kraft lignin depolymerisation, isotopic labelling reactions were completed in the presence of deuterated solvents as well as deuterium gas. This gave information on how Kraft lignin depolymerises, the influence of solvent to products formation and the involvement of hydrogen in the rate determining steps in the reactions. These results have led to an initial mechanistic understanding on how this complex molecule may yield alky-phenolic compounds. It was revealed that the solvent was directly involved in the products’ formation and that they were not generated by simple thermolysis. In addition, the presence of catalysts and hydrogen influenced product formation. The compounds showed different kinetic isotopic values, suggesting that each of these molecules came from individual mechanisms, highlighting the complexity of their formation. This was a relevant study as most of lignin depolymerisation mechanistic insights are based on model compounds and not on lignin itself. It was of interest to this project to explore not only different catalysts and their relationship to lignin depolymerisation, but also different lignin types. A simple pre-treatment for lignin extraction using sawdust (from oak and birch wood) in a Parr autoclave reactor in the presence of hydrogen, solvent and high temperature was developed. The lignins obtained after the pre-treatment were named parr-lignin and successfully resulted in polyaromatic molecules with less condensed character compared to lignins from Soda or Kraft pulping. Reactions were carried out with these lignins and a sugar-cane lignin. 4 5 Different catalytic systems with these lignins were investigated and how depolymerisation was affected by the metal and support used. The catalysts involved in the reactions included platinum, rhodium, nickel and iron. Various supports such as alumina, zirconia and carbon were tested along with the metals described. It was found that the supports were not inert in these experiments presenting catalytic activity. Materials with low surface area (zirconium catalysts) gave a poor performance compared to the others. In addition, nickel, a non-noble metal, showed as good a catalytic effect in the depolymerisation of these lignins as Pt and Rh. The components in the system influenced the reactions to different extents, especially product distribution. The catalysts had different selectivities and the solvents were not only dissolving lignin but also influencing the results. GPC analysis was performed to give an overview of the condensed level of these lignins and degrees of depolymerisation compared to the original material. GC-MS enabled the identification and quantification of 18 monomeric compounds. The post reaction characterisation of selected alumina catalysts (Pt/Al2O3, Ni/Al2O3 and Al2O3) was performed using XRD, BET, CHN, TPO and Raman Analysis to study the nature of the carbonaceous layer deposited on these materials. The work showed that after reaction the catalysts turned black in colour and the carbon laydown consisted of not only one simple type of carbon, and included graphitic species. The amount of carbon deposited depended on the type of lignin. Oak and birch parr-lignins had the highest and lowest amount of carbon over the catalysts respectively. No obvious trend relating to the type of catalyst, lignin and solvent used to the carbon nature was identified. This work showed that lignins with less condensed nature were less susceptible to solvolysis and more to hydrogenolysis. For example, sugar-cane lignin gave 3.9% of phenolic compounds in the solvolysis while reaction with Rh/Al2O3 gave 12.9% of products. This indicated that more selective cleavage of bonds were promoted by heterogenous catalysts. The results suggested that some compounds were mainly generated via dealkylation and hydrodeoxygenation, allowing a future possibility to generate target molecules. These results were mainly due to the presence of more labile bonds, vulnerable to hydrogenolysis. Highlighting that prior to depolymerisation, the pre-treatment used to extract lignin must be appropriate to avoid depletion of the alkyl-aryl ether bonds (β-O-4 bonds, especially) relevant for fine chemicals generation.
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Cui, Zheng. "Framework for Developing Countries’ Sound Management on Industrial Chemicals". Thesis, KTH, Industriell ekologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-58647.
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Industrial chemicals have become an integral part of modern life, and they infiltrate into a lot of activities of human beings, such as industrial manufacturing, agriculture, pharmaceutics, etc. Globalization brings opportunity and challenge to developing countries on the sound management of industrial chemicals (SMC). The issue is the contradiction between unmatched increasing import and consumption and weak legislation on SMC in developing countries. Consequently, more health and environmental impacts have been reported in developing countries because they lack capacities to generate sufficient information on chemical risks as well as appropriate methods for assessment and monitoring. Developed countries and IGOs (Intergovernmental Organizations) have made a lot of efforts on sound management of chemicals since 1960s. However, these efforts remain highly fragmented at international and national levels. As a result, a clear and well articulated strategy and concerted efforts from the international community to help developing countries is required. The aim of this thesis is, based on the studies of existing guidelines made by different IGOs on SMC, to suggest an integrated framework which can be used to collaborate with these scattered efforts together, to create synergies and avoid overlaps. This suggested framework consists of an executive mechanism which includes a panel of international organizations and general guidelines on SMC. Such a framework, looking like a voluntary intentional framework, provides possibilities to improve the capacity of developing countries’ management on industrial chemicals. To effective the framework, it needs shared responsibility of many actors to work together with same objectives to reduce adverse effects on human health and the environment. So this thesis just make a hypothesis based on the study of existing status on SMC, do the feasibility discussion and collect some feedbacks from IGOs as well.
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Nkomo, Sithethi Espin. "Using rheometry for prediction the pumping characteristics of highly concentrated W/O emulsion explosives". Thesis, Cape Peninsula University of Technology, 2005. http://hdl.handle.net/20.500.11838/912.
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Dissertation submitted in fulfilment of the requirements for the Masters Degree in
Technology: Chemical Engineering in the Department of Chemical Engineering of
Cape Peninsula University ofTechnology, 2005The emulsion used for this study is a new thermodynamically unstable multi-component waterin- oil (w/o) explosive type with an internal phase ratio of approximately 94%, i.e. far beyond the close packing limit of spherical droplets of 74%. Economic considerations and the ongoing need for continuous drilling, loading and blasting in the mining industry, has made long-distance pipeline transportation of these emulsion explosive systems a viable economic option. Presently, rheological characterization of emulsion explosives is well documented (Bampfield & Cooper, 1988, Utracki, 1980). However, very little or none has been done for this system, pertaining to the use of rheometry for prediction of pumping characteristics of these systems in long-distance pipeline transport. This Master's dissertation is devoted to develop rheological methods of testing, characterization and correlation in order to develop a basis for predicting the pumping characteristics of highly concentrated w/o emulsion explosives from rheometry. The literature and theory pertinent to the pipeline flow of high internal phase ratio emulsion explosives are presented, as well as the fundamentals of both concentric cylinder rheometry and pipe viscometry. The most relevant is the work of Bampfield and Cooper (1988), Utracki (1980) and Pal (1990). Two experimental test facilities were used for data collection. Pipeline experiments were done using an experimental test facility at African Explosives Limited (AEL), and rheometry was conducted at the Rheology Laboratory of the Cape Peninsula University of Technology Flow Process Research Centre. The AEL experimental test facility consisted of a four-stage Orbit progressive cavity pump, two fluid reservoirs, (a mixing tank and a discharge reservoir), five 45m HOPE (high density polyethylene) pipes of internal diameters of 35.9 mm, 48.1 mm, 55.9 mm, 65.9 mm and 77.6 mm pipes. The test work was done over a wide range of laminar flow rates ranging from 3 kg.min-I to 53 kg.min-I . Rheometry was done using a PaarPhysica MCR300 rheometer, and only standard rotational tests (i.e. flow curve) at 30 °c in controlled rate mode were done. Rheological characterisation was done using three rheological models, i.e. the Herschel-Bulkley, the Power Law and the Simplified Cross models. The coefficients obtained from these models were then used to predict pumping characteristics. The performances of these models were then evaluated by comparing the pipeline flow prediction to the actual pipeline data obtained from pipeline test experiments. It was found that the flow behaviour depicted by this explosive emulsion system was strongly non-Newtonian, and was characterized by two distinct regions of deformation behaviour, a lower Newtonian region of deformation behaviour in the shear rate region lower than 0.001 S-I and a strong shear thinning region in the shear rate range greater than 0.001 S-l. For all the models used for this study, it was evident that rheometry predicts the pumping characteristics of this high internal phase ratio emulsion reasonably well, irrespective of the choice of the model used for the predictions. It was also seen that the major difference between these models was in the lower shear rate domain. However, the Simplified Cross model was preferred over the other two models, since its parameter (the zero shear viscosity denoted by 110) can in general be correlated to the structure of the emulsion systems (i.e. mean droplet size, bulk modulus, etc.). Thus, structural changes induced by shearing (either inside the pump or when flowing inside a pipe) can be detected from changes in the value of the 110. The above statement implies that Tlo can be used as a quality control measure. Different pumping speeds were found to cause different degrees of shear-induced structural changes which were manifested by two opposing processes. These two opposing processes were the simultaneous coalescence and flocculation of droplets encountered at low rates of shear, and the simultaneous refinement and deflocculation of droplets encountered at high rates of shear. These two droplet phenomena were associated with a decrease or an increase in viscous effects, leading to both lower and higher viscous stresses and pumping pressures during pump start-up respectively.
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Jeffs, Corinne Ailsa. "Removal of toxic industrial chemicals using novel adsorbent hollow fibres". Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.665437.
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The current military respirator provides protection from contaminants using a cartridge packed with adsorbent activated carbon particles treated with metal salts to provide protection from toxic gases. However, the user of this respirator is subject to a physiological burden as a result. One component of this burden is the pressure drop, which makes breathing through the respirator filter difficult, with the burden becoming more severe at higher breathing rates. This project investigates the reduction of pressure drop and hence burden in respirator cartridges by using adsorbent hollow fibres. These are made up of adsorbent powder held together with a polymer binder to replace the conventional adsorbent particles. Adsorbent hollow fibres have a number of advantages, including lower pressure drop, the ability to operate in any orientation, no special filling requirements and customisability against emerging threats, such as toxic industrial chemicals. Dynamic challenges were performed using ammonia, hydrogen sulphide and cyclohexane as candidate gases, as each typifies a particular category of toxic industrial chemicals. Adsorbent hollow fibres were customised by treating with metal salts, metal organic frameworks and pore forming agents, and by replacing the hollow fibre polymer binder with a novel microporous polymer. In addition, the pressure drop of these adsorbent fibres was compared to granular beds. Pressure drop was then modelled using the Hagen-Poiseuille equation, and the breakthrough time was modelled with the Wheeler-Jonas equation, enabling the prediction of pressure drop and breakthrough time for new designs of adsorbent hollow fibre cartridges.
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Lee, Su-Gil. "Dermal and ocular exposure during the spray application of selected industrial chemicals /". Title page, abstract and table of contents only Title page, abstract and table of contents only, 2004. http://web4.library.adelaide.edu.au/theses/09PH/09phl4770.pdf.
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Kindt, Rocky. "Characterization of secondary microbial communities in industrial bioreactors producing high value chemicals". Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/28856.
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Microbial communities are key drivers of biogeochemical cycles and several important industrial processes rely on complex, undefined microbial ecosystems for production or conversion of substrates for example in wastewater treatment or anaerobic digestion plants. Despite their significance, such communities are often poorly defined, if at all. This project concerned previously undefined secondary microbial communities (SMCs) from photobioreactors culturing cyanobacterium Arthrospira platensis, known for producing high-value protein-pigment complex C-phycocyanin (C-PC). C-PC has a range of applications in the biochemical/pharmaceutical and food industries. Next-generation sequencing methods were applied to characterize the SMCs sampled over the course of various batch runs. The bioreactor exerted a strong selective pressure on the SMC, initially diverse and dynamic, succeeded by a stable and predictable SMC dominated by a few species. SMC stability and diversity correlated with reactor performance, especially proliferation and instability of the rare-abundance sub-population; dominant species ratios were likely less important. The substantially larger (compared to other species present) A. platensis filaments may represent a dynamic microenvironment in itself, and if so, constitutes a significant parameter when optimizing culture conditions. Denser and carefully pre-acclimated inocula reduce the ecological space available to undesirable taxa (e.g. pathogens) otherwise below detectable/significant limits. This has implications for other processes that rely on mixed cultures and may be a control strategy in manufacturing active pharmaceutical ingredients to cGMP standards. Molecular data was used to obtain several pure isolates which were characterized further. Strategies to optimize performance with respect to SMCs were explored and evaluated. A significant aspect of this CASE project was an industrial placement with Scottish Bioenergy. The placement involved set-up of a production facility and incremental scale-up of cultivation from 2 L to 1000 L reactors; development of a downstream processing protocol covering harvesting, pigment extraction and protein purification, and some formulation/stability testing. A very low-cost method is described for obtaining relatively high-purities of C-PC, broadly considered the most costly part of the entire production process.
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Eshtaya, Majd. "Towards sustainable production of renewable chemicals from lignin". Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/38392/.
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Environmental concerns have brought attention to the requirement for more efficient and renewable processes for chemicals production. Lignin is the second most abundant natural polymer, and might serve as a sustainable resource for manufacturing fuels and aromatic derivatives for the chemicals industry after being depolymerised. In this work, two main approaches were investigated with the aim of treatment of lignin with a mediator, 2,2’-azinobis(3-ethylbenthiazoline-6-sulfonic acid) diammonium salt (ABTS), in 1-ethyl-3-methylimidazolium ethyl sulfate, ([C2mim][C2SO4]). In the first approach, laccase from Trametes versicolor (LTV) was used to treat organosolv lignin, using [C2mim][C2SO4] as a co-solvent in the presence of ABTS. LTV was shown to possess catalytic activity for the degradation of organolsov lignin in systems containing ionic liquid and syringaldehyde was found to be a major product obtained from the process. ABTS alone has been evaluated for its reaction with lignin by means of cyclic voltammetry (CV). Here, the non-phenolic lignin model compound veratryl alcohol and three types of lignin (organosolv, Kraft and lignosulfonate) were specifically examined. The presence of either veratryl alcohol or organosolv lignin increased the second oxidation peak of ABTS under select conditions, indicating the ABTS-mediated oxidation of these molecules at high potentials in [C2mim][C2SO4]. Furthermore, CV was applied as a quick and efficient way to explore the impact of water in the ABTS-mediated oxidation of both organosolv and lignosulfonate lignin. Higher catalytic efficiencies of ABTS were observed for lignosulfonate solutions either in sodium acetate buffer, or when [C2mim][C2SO4] (15% v/v) was present in an aqueous solution, whilst there was no change found in the catalytic efficiency of ABTS in neat [C2mim][C2SO4]-lignosulfonate mixtures relative to ABTS alone. In contrast, organosolv showed an initial increase in oxidation, followed by a significant decrease on increasing the water content of a [C2mim][C2SO4] solution. Despite enhanced lignin solubility in ionic liquids, the yields of small molecules attributed to depolymerisation in ionic liquids are often quite low. Since depolymerisation approaches examined herein are thought to proceed via free-radical mediated mechanisms, two different stable radicals 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ABTS were assessed for the rapid monitoring of radical activity of lignin-related compounds in ionic liquid systems. While these assays are successful in aqueous and organic solvent systems, the presence of the ionic liquids complicates the assay procedure, requiring further developmental work.
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Noisuwan, Angkana. "Effects of milk protein ingredients on physico-chemical properties of rice starch : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology at Massey University Palmerston North, New Zealand". Massey University, 2009. http://hdl.handle.net/10179/905.
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The overall aim of this thesis is to determine if the interactions between normal and waxy rice starch and milk proteins from four milk protein ingredients, namely skim milk powder (SMP), milk protein concentrate (MPC), sodium caseinate (NaCAS) and whey protein isolate (WPI) do occur, and to identify the mechanisms underlying these interactions. Different milk protein ingredients at various concentrations (0 to 10%, w/w) affected markedly and differently the pasting behaviour of 10% (w/w) rice starches. SMP delayed the pasting of both rice starches by increasing the onset temperature (Tonset) and the peak viscosity temperature (Tpeak) of pasting. This was mainly due to the presence of lactose and ions, which was further supported by the investigation of the effects of UFSMP (a solution of salts and lactose present in SMP at their proper concentration) and lactose. The addition of NaCAS also delayed the pasting of rice starch; Tpeak in the case of both starches was increased. For normal rice starch paste, MPC and WPI decreased the Tpeak. MPC had no affect on Tpeak of waxy rice starch paste. The qualitative viscoelastic behaviour of rice starch/milk protein ingredient gels obtained from the above pastes was dominated by the continuous phase made of the starch molecules. There was evidence, as indicated by confocal microscopy, of phase separation between the milk proteins of SMP and MPC and the two starches. The phase separation was not observed in the addition of either NaCAS or WPI. Studies on the thermal behaviour of rice starch/milk protein ingredient mixtures by differential scanning calorimetry (DSC) showed that SMP, similarly to UFSMP, delayed the gelatinization of both starches. NaCAS also delayed the gelatinisation of both starches but had a greater effect on waxy than normal rice starch. The addition of NaCAS did not affect Tonset but increased Tpeak for normal rice starch, whereas the gelatinisation temperature of waxy rice starch was highly affected by the addition of NaCAS with both Tonset and Tpeak shifted to higher temperatures. MPC had no affect on the gelatinization temperature of normal rice starch, whereas the gelatinization temperature of waxy rice starch was increased by the addition of MPC. The addition of WPI to both rice starches showed two thermal transitions. The first of these was due to the gelatinisation of the starches and the second to the denaturation of ß-lactoglobulin (ß-lg). The addition of WPI to normal rice starch showed that the thermal behaviour of normal starch and protein were independent from each other. In contrast, the thermal behaviour of waxy rice starch was modified by the addition of WPI; both Tonset and Tpeak were increased. SMP decreased the Tonset of swelling, swelling ratio and the amount of starch leaching from both starches. These observed changes were due to the presence of lactose and ions in SMP. NaCAS slightly increased Tonset of swelling but the amount of starch leaching was reduced for both rice starches. The rigidity of both starches tended to increase in the presence of NaCAS. MPC and WPI affected the swelling behaviour of normal and waxy rice starch differently. A dramatic increase in the swelling of normal rice starch/MPC or WPI mixtures was observed, whereas this trend was not evident for waxy rice starch/ MPC or WPI mixtures. The difference in the water holding ability and gelatinization peak temperatures of the two starches over the temperature range at which whey proteins denature and form gels are believed to be responsible for the observed differences. The results from confocal microscopy showed that milk proteins, such as a-casein, ß- casein, ß-lg and a-lactalbumin (a-la), were adsorbed onto the granule surface of both normal and waxy rice starch. The mechanism for this adsorption is the hydrophilic interactions; hydrogen bonds between hydroxyl group from terminated glucan molecule that protrude around starch granule surface-hydroxyl; amino, or other electron-donation or electron-accepting groups of the added proteins. Using sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE) it was found that for SMP and MPC the adsorbed as- to ß-casein ratio on both starches was similar to the as-casein to ß- casein ratio in the casein micelle at low SMP and MPC concentrations. But at high concentrations of SMP or MPC, this ratio decreased indicating that more ß-casein was adsorbed preferentially to as-casein. In the case of NaCAS, as-casein was adsorbed preferentially to ß-casein. Moreover, there was evidence of multilayer adsorption of ascasein into the surface of rice starch granules. Compared to the other milk protein ingredients, very small amounts of the ß-lg and a-la from WPI were adsorbed onto starch granules. However, the adsorbed amounts of ß-lg and a-la from WPI continuously increased with increasing WPI concentration, suggesting that these two proteins, particularly ß-lg, adsorbed in multilayers too.
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Pooni, Gurkanwal Singh. "The creation and development of technology by MNEs within the chemical, pharmaceutical and biotechnology industries". Thesis, University of Reading, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393242.
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Anandarao, Venkatesh, i Sukrit Reddy Bandi. "Factors affecting the adoption of solar thermal technology : A study on Food and Chemical Industries". Thesis, Uppsala universitet, Industriell teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-447169.
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The rising concerns of climate change and global warming have made the current practices of industrial energy generation and consumption highly unsustainable. There is a growing awareness of the importance of renewable energy use in addressing climate change and establishing sustainable development. One of the renewable sources which have gained popularity over time is solar energy. Among the various solar technologies, one potential segment is solar thermal technology which involves solar thermal collectors. This technology mainly concentrates on providing industrial process heat across a wide range of temperature, and it's classified within the industry of Solar Heat for Industrial Process (SHIP). Though the SHIP technologies show strong technical feasibility, only few industries employ solar heat and there is a decreasing trend of adoption. Hence, this research aims to understand the reasons for decreasing adoption by studying what and how are the factors affecting the adoption of solar thermal technology. This is done by performing a qualitative study across two industrial sectors food and chemical in the region of Middle East and North Africa (MENA). The obtained data by conducting semi-structured interviews are analysed using the Technological-Organization-Environment (TOE) theoretical framework. The results from the study show that there are 9 important factors affecting the adoption of solar thermal technology that are categorized into technological factors (reliability, flexibility, financial attractiveness, and competitive alternatives), organizational factors (management support and resources) and environmental factors (regulatory environment, technology support provider and competitive pressure). Apart from the technological factors of lack of reliability and financial attractiveness, the organizational factors of lack of resources and the environmental factor of low incentives in MENA region, the aspect of cheap competitive alternatives especially in the MENA region, is causing the decrease in adoption within the food and chemical industry.
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Chan, Wai-man. "The control and management of dangerous substances and chemicals in Hong Kong /". Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19945711.
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Innocenti, Giada <1991>. "Catalysis for chemicals production from bio-based building blocks: examples of industrial relevance". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amsdottorato.unibo.it/8764/1/Tesi_Dottorato_Giada_Innocenti.pdf.
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The research work presented in this PhD thesis is focused on two research topics which aim is to enhance the sustainability of the modern biorefinery. In fact, the production of an advanced biofuel such as 1-butanol is studied in the first part, while the second part deals with the valorisation of glycerol, which is a biodiesel co-product.
Therefore, in the first part of the thesis 1-butanol production by means of the Guerbet reaction is studied. The catalytic synthesis of 1-butanol is more desirable than ABE fermentation because it allows to reach higher productivity, lowering the separation costs. The study is aimed to provide a deeper understanding on the effect of acid and base active sites. Therefore, pure basic alkaline earth metal oxides were synthesized and fully characterized. Afterwards, the oxide which showed the best performance was doped with H3PO4 and its catalytic behaviour was studied. Finally, its performance was compared with that one of hydroxyapatite, even with respect to its lifetime.
Dihydroxyacetone, a glycerol derivative, upgrading into lactic acid is the topic of the second part of this work. Glycerol valorisation into chemicals might help to support the economic sustainability of biodiesel production. In fact, its disposal as a waste is expensive and not sustainable according to the biorefinery concept. Therefore, a continuous process aimed at directly upgrading glycerol is highly desirable. The main problem in dihydroxyacetone conversion is the need for water-resistant catalysts. A continuous process is more convenient from both an economical and a technological point of view than a batch one. In this thesis, a thorough study of metal phosphate-based catalysts reactivity in the aqueous phase and in a continuous-feed reactor is presented. The catalysts were fully characterized in order to understand the relationship between their physico-chemical characteristics and catalytic performance.
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Reed, Susan, of Western Sydney Hawkesbury University i of Science Technology and Environment College. "Development of method to assess skin contact to chemicals". THESIS_CSTE_XXX_Reed_S.xml, 2001. http://handle.uws.edu.au:8081/1959.7/611.
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Chemical exposure of the skin has become a route of entry of some chemicals into the body and has come under major review in recent times. This research aims to develop a method of estimating skin exposure that is both reliable and non-prohibitive in cost. This involved the design and testing of skin patches adaptable for monitoring skin exposure to chemicals using several different types of absorbents which could be easily worn against skin. The final design of the patch used either activated charcoal or tenax as the absorbing medium. The patches were then desorbed with a solvent in order to analyse the chemicals. The results of the study showed that many skin exposures do not have a direct relationship with inhalation exposures, which is important because currently there are no estimates of the levels of skin exposures that may have potential long term health effects. The patch has proved successful for detecting the presence and determining the amount of chemicals that come in contact with the skin. Charcoal patches have the widest application, but are not suitable for all situations and tenax should be used on these occasions.Doctor of Philosophy (PhD)
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Blaine, Jonathan Andrew Lindley. "Preparation and characterisation of cluster-derived, multimetallic nanoparticles and their catalytic activity in industrially important transformations". Thesis, University of Southampton, 2013. https://eprints.soton.ac.uk/360884/.
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Multimetallic molecular cluster compounds have been synthesised and characterised. They have been used as precursors for the generation, by heating under vacuum, of nanoparticles supported within the pores of mesoporous silica. By following their activation using infrared spectroscopy, it has been revealed how the temperature of thermolysis determines the nature of the active site. Through spectroscopic investigations of the active sites, the effect of altering the structure and stoichiometry on the surface metal sites has been elucidated. It has been shown how the inclusion of an oxophilic main group element in the precursor both improves the site isolation of the active sites and affects the oxidation states of the other metals present in the catalyst. The inclusion of an oxophile changes the nature of the bonding between the nanoparticle and the surface and presents different metal atoms at the nanoparticle surface, altering its catalytic activity. The selection of oxophile is crucial to the activity of the catalyst, since it is possible for it to form a key part of the active site, either purely as a coordination site or indeed as part of the redox system. The use of a molecular cluster precursor greatly enhances this synergistic effect, by ensuring the different metal atoms are chemically bound throughout catalyst preparation, activation and use.
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Rowat, Alison. "Improved penetration of chemicals during chemi-mechanical pulping with anthraquinone". Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=24070.
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The objectives of this work were to investigate and improve impregnation of regular (2-8mm thickness range) black spruce wood chips in CMP-AQ pulping. Impregnation and pulping experiments were performed while varying several pulping parameters. Experiments were analyzed in terms of yield, lignin content, percent screen rejects, and strength properties. The goal was to determine optimum pulping conditions that would improve chemical impregnation. Impregnation is a function of percent screen rejects: well impregnated chips have fewer rejects.Cooking temperature and cooking time were held constant in all experiments at 170$ sp circ$C and 30 minutes, respectively. The liquor pH was adjusted to 7.9 and a liquor-to-wood ratio of 6:1 was used. Presteaming pressure was held constant at 138 kPa and soaking temperature was maintained isothermal at 90$ sp circ$C.
Process variables which can influence the chemical penetration were investigated. These are: wood chip thickness, pre-treatment agents, compression ratio, partial crushing of wood chips, and also pre-steaming and evacuation prior to chemical treatment as a possible method of entrapped air removal. Additional process parameters investigated were the concentration of pulping chemicals and dosage of AQ catalyst.
The advantages provided by the use of thinner wood chips, caustic pretreatment and high compression prex-impregnation were confirmed for improving chemical impregnation. The addition of SAQ catalyst to the CMP pulping process produced pulps of unusually high screened yield for given lignin content. Improvements were also observed in strength properties compared to the control cook where no SAQ was used.
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Johansson, Alexandra. "Pedagogisk kartläggning av introduktionsutbildning för nyanställda operatörer : Analys av kunskapsnivå inom kemi i produktutbildning". Thesis, KTH, Lärande, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-297457.
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Företag med en omfattande produktionshastighet ställer krav på en viss kvalitet på sin produkt, särskilt inom läkemedelsindustrin. Misstag kan leda till att en hel sats går till spillo och sannolikheten för misstag påverkas av de anställdas kompetens. Nyanställdas introduktion till arbetet är därför en viktig faktor för att minimera förlust. Studiens syfte är att analysera utbildning för nyanställda operatörer inom AstraZeneca Sweden Operations, vilket genomförs i två delstudier med olika perspektiv. Utifrån analyserna ges sedan förbättringsförslag till utbildningarna. Första delstudien fokuserar på en nyligen bearbetad introduktionsutbildning utifrån ett pedagogiskt perspektiv med teorier om effektivt lärande och läroplansteori. En överblick erhålls genom en blandning av intervjuer, observationer och dokumentation. Andra delstudien fokuserar på vilka förkunskaper i kemi som operatörer förväntas ha utifrån kunskapsnivån som presenteras i utbildningsmaterial. Materialet jämförs sedan med kemi på gymnasienivå. Resultat från första delstudien visar att introduktionsutbildningens upplägg har flera faktorer som bidrar till ett mer effektivt lärande, vilket även bekräftas under intervjuer med operatörer och utbildare. Utvecklingsförslag är att implementera ett styrdokument som genomsyrar utbildningen inom hela företaget samt att använda en modell för effektivt lärande vid ändring av lärandeaktiviteter. Den andra delstudien visar på att utbildningsmaterialet är på högre nivå än vad som krävs som förkunskap för tjänsten. För att minimera kunskapsklyftan kan olika pedagogiska verktyg användas i undervisningen när nya begrepp och processer introduceras. Som exempel på detta har en analogi för reningsprocessen kristallisation tagits fram.Sammanfattningsvis visar detta arbete att den utarbetade introduktionsutbildningen är väl utvecklad utifrån ett perspektiv om effektivt lärande medan den mer detaljerade produktutbildningen behöver andra pedagogiska verktyg för att möta operatörerna på deras befintliga kunskapsnivå.Companies with an extensive production rate demand a certain quality of their product, especially in the pharmaceutical industry. Mistakes can lead to an entire batch being wasted which is affected by the employees' skills. New employees' introduction to work is therefore an important factor in minimizing losses. This study is divided into two parts. The purpose of the study is to analyze training for newly hired operators within AstraZeneca Sweden Operations, which is carried out in two sub-studies with different perspectives. Based on the analyzes, suggestions for improvement are given to the educations. The first part of the study focuses on a recently processed introductory education from a pedagogical perspective with theories of effective learning and curriculum theory. An overview is obtained through interviews, observations and documentation. The second sub-study focuses on what prior knowledge in chemistry that operators are expected to have based on the level of knowledge presented in teaching materials. The material is then compared with chemistry at upper secondary school level. Results from the first sub-study show that the introductory training has several factors that contribute to more effective learning, which is also confirmed through interviews with operators and educators. Suggestions for improvement are to implement a document that permeates the education within the entire company and to use a model for effective learning when improving learning activities.The second sub-study shows that the teaching material is at a higher level than what is required as prior knowledge for the position. To minimize the gap, pedagogical tools can be used in teaching when new concepts and processes are introduced. As an example of this, an analogy for the crystallization process of crystallization has been developed.In summary, this work shows that the prepared introductory education is well developed from a perspective of effective learning, while the more detailed product lecture needs more pedagogical methods to meet the operators at their existing level of knowledge.
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Waldemarsson, Martin. "Planning production and supply chain in energy intensive process industries". Doctoral thesis, Linköpings universitet, Produktionsekonomi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-112289.
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To make a difference among the energy intensive process industries, this dissertation addresses production planning and supply chain planning problems related to industrial energy management issues. The energy issue is turning more and more important from different angles, involving price as well as environmental problems due to climate change leading to political pressure on all energy users. The process industry sector is one of the largest users of energy, and thus important to analyse. Process industries are also capital intensive and operate on large and expensive process equipment, making it imperative to plan their production well in order to reach preferable capacity utilisation. Therefore this dissertation strives to locate the most important energy management issues for the long term profitability of process industries, and investigates the symbiotic effects of including energy issues in production and supply chain planning. Three different studies at three case companies are carried out, analysed, and presented in five papers. The cases represent the process industry sectors: chemicals, pulp, and steel. Both qualitative case study methodologies as well as quantitative mathematical modelling and optimisation approaches have been practiced. The research questions are analysed from both an energy system and from a production process point of view, separately as well as combined. Energy is somewhat considered to be the main workforce for process industries and this dissertation exemplifies some of its most important dimensions in this context. Several prerequisites for putting energy management on the strategic agenda are located in a specialty chemical industry where the importance of introducing a strategic perspective on energy, the way energy is used, and the possibilities of increasing alternative revenue from utilising by- and/or co-products differently are pinpointed. Approaches for including energy issues in planning processes are also suggested in terms of a MILP model for the entire supply chain of a pulp company, including decisions on purchase and transportation of raw maerials, production allocation, energy mix, and distribution. Another example is presented based on the perspectives of economics of scale and lot sizing through economic order quantity principles in a steel company. By using real company data, energy smart approaches in planning and scheduling are developed with respect to the most important intersections between the production processes and their supporting energy system. The accumulated resource intensity and embedded energy could, and probably should, hence be more fairly reflected in the product price. The research finally shows some possible impact with including energy issues in a production and supply chain planning model. By planning differently, production prioritisations can be done, and it is not only possible without any large investments, but also prosperous with savings on both energy and money within reach. To conclude, planning of production and supply chain has either a direct or an indirect impact on the energy cost-effectiveness of a company. This dissertation argues that such impact also exists in its mutual form, and is very important when the energy issues are large enough, as they often are in the energy intensive process industry sector. Decision makers should thus beware of the short end of the stick that might be devastating in the long run, but also aware of all the possibilities that can bring success and prosperity when the future begins.
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Loponov, Konstantin Nikolayevich. "Development of a scalable photochemical reactor for syntheses of fine chemicals". Thesis, University of Warwick, 2011. http://wrap.warwick.ac.uk/35523/.
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This study is in the area of sustainable chemical technology and is ultimately aimed at developing a novel generic approach towards efficient, clean, safe and scalable synthesis of important intermediates for pharmaceutical applications and catalysis using nonthermal activation of chemical bonds. Current study is focused on molecular activation by light, specifically addressing the class of singlet oxygen reactions. A laboratory-scale annular recirculating photoreactor and a scalable microreactor unit were designed, assembled and tested in oxygenation of α-pinene and stereoselective oxygenation of homoallylic alcohols by the photogenerated singlet oxygen. Efficiencies of light utilization and the quantum yields of the reactions for different sources of light in various lamp-reactor geometries were quantified using actinometry. It was shown that optimal thickness of the reaction layer, high intensity of light and elevated oxygen pressures in continuous gas-liquid segmented flow are crucial for both safe and efficient oxygenation. This study proved the viability of a novel concept of compact reactors with embedded light emitting diodes. Finally, a methodology of efficient oxyfunctionalization of allylic compounds was developed. Following the developed methodology, the applicability of functional nanomaterials based on pure and dye-modified porous silicon as heterogeneous photosensitizers of singlet oxygen was studied in detail. It was demonstrated that the photosensitizing efficiency of all the samples is much lower than that of conventional dye photosensitizers. Low activity of the novel photosensitizers was attributed to quenching of the photogenerated singlet oxygen by the surface quenching groups of porous silicon, low quantum yield of photoluminescence in the case of pure porous silicon and to thermodynamically favorable quenching of the photoexcited porphyrin states due to energy/electron transfer to silicon nanocrystals in the case of dye modified porous silicon.
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Harris, Catherine Anne. "The endocrine disrupting activities of major industrial chemicals - the phthalate esters and 4-nonylphenol". Thesis, Brunel University, 2000. http://bura.brunel.ac.uk/handle/2438/4974.
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A number of widely used industrial chemicals have been shown to possess endocrine-disrupting properties. In this thesis, a series of in vitro tests, and an in vivo reproductive performance test with fathead minnows, were used to clarify the extent of estrogenic activity exhibited by the phthalate esters - a class of compound hitherto referred to as 'estrogenic'. Using a recombinant yeast estrogen screen, I demonstrated that a small number of commercially available phthalates showed extremely weak estrogenic activity. The most potently estrogenic phthalate of those tested was BBP, which was approximately one million-fold less potent than 17B-estradiol. The phthalates which were estrogenic in the yeast screen were also mitogenic on estrogen-responsive human breast cancer cells (MCF-7 and ZR-75 cell lines). The most prolifically used phthalate, DEHP, was not estrogenic in any of these assays. The small number of metabolites of phthalate metabolites tested (including MBuP, MBzP, MEHP and MnOP) were also not estrogenic in the recombinant yeast assay. The ability of BBP (as the most potently estrogenic phthalate in vitro) to induce a vitellogenic response (an indicator of estrogen exposure) in fathead minnows (Pimephales promelas) exposed via the water was assessed. No induction of vitellogenin was observed, indicating that 100 Jlg BBP/L (a concentration higher than would normally be found in the environment) is not estrogenic to this species of fish under the conditions employed for this experiment. In the same study, fecundity of breeding pairs of fathead minnows was assessed; exposure to BBP was not found to affect reproductive performance in these fish. A possible alternative mechanism of action of the way in which the phthalates induce frequently reported reproductive disorders was observed. Some of the phthalates, and, notably, some of their metabolites, were demonstrated to act as anti-androgens in a recombinant yeast androgen assay. 4-Nonylphenol is another industrial chemical which is used in large volumes, and due to the nature of its use (mainly in detergent formulations), is discharged into water systems via sewage effluents. This chemical has been shown to be estrogenic to fish at the concentrations at which it has been detected in the environment. 4-Nonylphenol was tested for its ability to affect plasma and pituitary gonadotropin levels in female recrudescing rainbow trout (Oncorhynchus mykiss). Plasma and pituitary levels of FSH were suppressed in fish exposed to 10 and 100 Jlg 4-NP/L. In addition, FSH gene expression was reduced in these fish, and also in the fish exposed to 1 Jlg 4-NP/L. Pituitary LH content and gene expression of this hormone were suppressed in the fish exposed to 100-, and 10- and 100 Jlg 4-NP/L respectively. Gonadal development in vertebrates is regulated by FSH. Ovarian development ceased in the fish exposed to 100 JAg 4-NP/L, possibly as a result of the suppression of FSH synthesis and/or release in these fish.
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MARCHESE, MARCO. "Conversion of industrial CO2 to value-added fuels and chemicals via Fischer-Tropsch upgrade". Doctoral thesis, Politecnico di Torino, 2021. http://hdl.handle.net/11583/2914540.
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Reed, Susan. "Development of method to assess skin contact to chemicals". Thesis, View thesis View thesis, 2001. http://handle.uws.edu.au:8081/1959.7/611.
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Chemical exposure of the skin has become a route of entry of some chemicals into the body and has come under major review in recent times. This research aims to develop a method of estimating skin exposure that is both reliable and non-prohibitive in cost. This involved the design and testing of skin patches adaptable for monitoring skin exposure to chemicals using several different types of absorbents which could be easily worn against skin. The final design of the patch used either activated charcoal or tenax as the absorbing medium. The patches were then desorbed with a solvent in order to analyse the chemicals. The results of the study showed that many skin exposures do not have a direct relationship with inhalation exposures, which is important because currently there are no estimates of the levels of skin exposures that may have potential long term health effects. The patch has proved successful for detecting the presence and determining the amount of chemicals that come in contact with the skin. Charcoal patches have the widest application, but are not suitable for all situations and tenax should be used on these occasions.
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Cannaday, Bruce D. "Basic concepts of industrial technology". Virtual Press, 1986. http://liblink.bsu.edu/uhtbin/catkey/458486.
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The purpose of this creative project was to develop a three dimensional model that would assist Industrial Technology Educators describe contemporary concepts of communication, construction, manufacturing, and transportation. The creative project was designed to appreciation of Industrial Technology. It also assisted them in developing problem solving techniques.A model community and activity packet were developed. The model community was the central focus for analysis. The concepts represented in the model community are reinforced with activities in the activity packet.
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Peiris, Dinithi. "Effects of known reproductive toxicants of sperm function and nuclear integrity in the hamster". Thesis, University of Sheffield, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287651.
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Reed, Susan. "Development of method to assess skin contact to chemicals /". View thesis View thesis, 2001. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030520.115134/index.html.
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Thesis (Ph.D.) -- University of Western Sydney, Hawkesbury, 2001.A thesis presented in fulfilment of the requirement for the degree of Doctor of Philosophy, College of Science, Technology and Environment, University of Western Sydney, Richmond, April 2001. Bibliography : leaves 138-148.
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Bellotti, Paulo Roberto. "Strategic management of technology in the chemicals/materials industry : policy recommendations for Brazil". Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/33496.
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Chang, Mary Yabut. "High technology and Macau industrial transformation". Thesis, University of Macau, 1997. http://umaclib3.umac.mo/record=b1636693.
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Awcock, Graeme John. "Image acquisition technology for industrial automation". Thesis, University of Brighton, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314802.
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Seabra, Rute Agostinha Gomes. "Carbon Dioxide Separation from Industrial Streams". Master's thesis, 2017. https://repositorio-aberto.up.pt/handle/10216/105918.
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Seabra, Rute Agostinha Gomes. "Carbon Dioxide Separation from Industrial Streams". Dissertação, 2017. https://repositorio-aberto.up.pt/handle/10216/105918.
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Araújo, Ângela Nogueira. "Desenvolvimento de Novas Formulações de Sabão Industrial". Master's thesis, 2018. https://hdl.handle.net/10216/114049.
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Araújo, Ângela Nogueira. "Desenvolvimento de Novas Formulações de Sabão Industrial". Dissertação, 2018. https://hdl.handle.net/10216/114049.
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Araújo, Ângela Nogueira. "Desenvolvimento de Novas Formulações de Sabão Industrial". Dissertação, 2002. https://repositorio-aberto.up.pt/handle/10216/114049.
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Queiroz, João Alegre. "Evaluation and Optimization of an Industrial Utility System". Doctoral thesis, 2016. https://hdl.handle.net/10216/99384.
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Almeida, Rita Teixeira. "Tratamento seletivo de um efluente industrial por adsorção". Master's thesis, 2020. https://hdl.handle.net/10216/132820.
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Almeida, Rita Teixeira. "Tratamento seletivo de um efluente industrial por adsorção". Dissertação, 2020. https://hdl.handle.net/10216/132820.
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Sousa, Marta Sofia Alves de. "Tratamento seletivo de um efluente industrial por adsorção". Master's thesis, 2019. https://hdl.handle.net/10216/122732.
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