This thesis describes methods to obtain value–addedcompounds from TMP-turpentine obtained from the spruce, Piceaabies. The methodology focuses on biotransformations using twoapproaches: an oxygenation approach (i.e. oxygenation ofterpene hydrocarbons by cell cultures) and an esterificationapproach (i.e. lipase-catalysed transesterification of vinylacetate with terpene alcohols, and a further fractionation ofthe TMP-turpentine). The main constituents of the turpentine, a-pinene, b-pineneand limonene, were subjected to a P. abies suspension culture.Allylic oxidation formed the major products for α-pineneand β-pinene, which were further oxidised to theirrespective aldehyde or ketone. One of the minor products froma-pinene, cis-verbenol, was not only transformed into verbenonebut also isomerised to trans-verbenol. Limonene gavelimonene-(1,2)-epoxide as the major product. Fractionation of monoterpenes is accomplished throughphysical separation methods, chromatography and distillation,and lipase-catalysed transesterification of vinyl acetate withterpene alcohols. The esters of myrtenol and trans-pinocarveolwere separated from the more slowly reacting alcohols such asborneol and carveol by use of a combination of the Mucor mieheilipase and Candida antarctica lipase A as catalysts.Furthermore, the non-reacting tertiary terpene alcohols wereseparated from the reacting alcohols in a single step byCandida antarctica lipase A. Lipase-catalysed (Candida antarctica lipase B andPseudomonas cepacia lipase) transesterification of vinylacetate with sterically hindered secondary alcoholsunexpectedly yielded hemiacetals or hemiacetal esters. Thereaction conditions required to obtain these side products havebeen studied. <b>Keywords:</b>Picea abies, Pinaceae, Essential oilscomposition; Terpene alcohol; Hemiacetal; Hemiacetal ester,TMP-turpentine; Monoterpene; α-Pinene; β-Pinene;Limonene; Verbenol; Pinocarveol; Borneol; Myrtenol; Suspensioncell culture; Biotransformation; Lipase-catalysed; Oxidation;Allylic oxidation; Transesterification; Autoxidation;Separation.

<p>This thesis describes methods to obtain value–addedcompounds from TMP-turpentine obtained from the spruce, Piceaabies. The methodology focuses on biotransformations using twoapproaches: an oxygenation approach (i.e. oxygenation ofterpene hydrocarbons by cell cultures) and an esterificationapproach (i.e. lipase-catalysed transesterification of vinylacetate with terpene alcohols, and a further fractionation ofthe TMP-turpentine).</p><p>The main constituents of the turpentine, a-pinene, b-pineneand limonene, were subjected to a P. abies suspension culture.Allylic oxidation formed the major products for α-pineneand β-pinene, which were further oxidised to theirrespective aldehyde or ketone. One of the minor products froma-pinene, cis-verbenol, was not only transformed into verbenonebut also isomerised to trans-verbenol. Limonene gavelimonene-(1,2)-epoxide as the major product.</p><p>Fractionation of monoterpenes is accomplished throughphysical separation methods, chromatography and distillation,and lipase-catalysed transesterification of vinyl acetate withterpene alcohols. The esters of myrtenol and trans-pinocarveolwere separated from the more slowly reacting alcohols such asborneol and carveol by use of a combination of the Mucor mieheilipase and Candida antarctica lipase A as catalysts.Furthermore, the non-reacting tertiary terpene alcohols wereseparated from the reacting alcohols in a single step byCandida antarctica lipase A.</p><p>Lipase-catalysed (Candida antarctica lipase B andPseudomonas cepacia lipase) transesterification of vinylacetate with sterically hindered secondary alcoholsunexpectedly yielded hemiacetals or hemiacetal esters. Thereaction conditions required to obtain these side products havebeen studied.</p><p><b>Keywords:</b>Picea abies, Pinaceae, Essential oilscomposition; Terpene alcohol; Hemiacetal; Hemiacetal ester,TMP-turpentine; Monoterpene; α-Pinene; β-Pinene;Limonene; Verbenol; Pinocarveol; Borneol; Myrtenol; Suspensioncell culture; Biotransformation; Lipase-catalysed; Oxidation;Allylic oxidation; Transesterification; Autoxidation;Separation.</p>

Abstract The objective of this thesis was to obtain new information about mechanisms of thermomechanical pulp refining in the inner area of a refiner disc gap by studying inter-fibre refining and by calculating the distribution of energy consumption in the refiner disc gap. The energy consumption of thermomechanical pulping process is very high although theoretically a small amount of energy is needed to create new fibre surfaces. Mechanisms of refining have been widely studied in order to understand the high energy consumption of the process, however, phenomena in the inner area of disc gap has had less attention. It is likely that this important position is causing high energy consumption due to the high residence time of pulp located there. The power distribution as a function of the refiner disc gap was calculated in this work. The calculation was based on mass and energy balances, as well as temperature and consistency profiles determined by mill trials. The power distribution was found to be dependent on segment geometry and the refining stage. However, in the first stage refiner with standard refiner segments, a notable amount of power was consumed in the inner area of the disc gap. Fibre-to-fibre refining is likely to be the most important mechanism in the inner area of disc gap from the point of view of energy consumption. In this work the inter-fibre refining was studied using equipment for shear and compression. Fibre-to-fibre refining was found to be an effective way to refine fibres from coarse pulp to separated, fibrillated and peeled fibres if frictional forces inside the compressed pulp were high enough. It was proposed that high energy of today’s thermomechanical pulping process could derive from too low frictional forces that heated pulp and evaporated water without any changes in fibre structure. The method to calculate power distribution and results of fibre-to-fibre refining experiments may give ideas for developing today’s thermomechanical pulp refiners’ or for developing totally new energy saving mechanical pulping processes.

Philosophiae Doctor - PhD / The research was prompted by two main issues prevalent in South African education in the last decade. These were particularly the critical state of the schooling system, especially in the educationally disadvantaged schools (mainly ex-Department of Education and Training) and the relationship of the teacher to teaching and the related issue of teacher upgrading. The resultant effect was that the educationally disadvantaged communities became more and more disadvantaged over time because of decreasing mental stimulation and mental development. The answer lay in finding a theory of intellectual growth and development which takes into account the learning environment of the disadvantaged child. The Educational Support Services Trust (ESST) has been active in addressing this very issue since 1986. It provides appropriate learner-centred mediational texts to disadvantaged pupils around the country. These materials concentrate on the development of practical intelligence by relating leaming to everyday experience. The Teachers' Methodology Project was designed to change the teachers who were using the ESST materials from being disseminators of information to being managers of a learning-centred classroom environment. The idea was to change the way that teachers thought about teaching and learning. This was accomplished by sharing the methodology of the existing pupils' materials and theories of cognition and mediation with them so that they could become adept at mediating at the level of deconstruction of complex ideas and using this knowledge in the construction and development of their own learning materials, thereby contributing to the mental development of their pupils. My experience as a staff member of the ESST and my background in education provided an entry point to this research via Feuerstein et at's (1980,1991) criteria for mediation, Haywood's (1993) mediational teaching style and a range of other theories and ideas including group work and co-operative learning, graphic organisers, and the ESSTs own theory of mediatory text (Sinclair, 1991). These were consolidated into a learning-centred approach to teaching in which the learner, the teacher and the task become part of the total learning-centred environment. The research began as an investigation of the Teachers' Methdology Project (TMP) and an effort to track teachers' development but grew to include the development of the conceptual mediational framework on which the project was based. This resulted in the development of a classroom observation instrument which was used to evaluate how teachers mediated in their classrooms and how they interacted with pupils. The TMP was implemented through a series of workshops during which teachers examined their assumptions about teaching and learning: explored new avenues for facilitating learning; experienced a learning-centred approach to teaching; acquired new strategies for and knowledge of, theories and atttitudes to teaching and learning and were able to reflect on and practise newly acquired skills in a supportive collegial environment. The research employed a qualitative approach and therefore the documentation of the process took considerable effort. An experiential framework (Kolb, 1974) was used to analyse the process and the results. This mediational experiential framework resulted in a methodology which addressed teachers' attitudes and cognition in a life-related way, taking into account their personal knowledge and experience. The methodology is replicable and has been used in basic adult education and other settings. In addition, the methodology can contribute to the understanding of how Outcomes-based Education could be implemented in South Africa.

Mediante la observación y análisis de los datos recolectados en el año 2020 en el área de mantenimiento de una empresa minera ubicada al sur del Perú, se logró identificar las razones de una baja disponibilidad de las palas dentro del proceso productivo de carguío. Es por ello, que se desarrolló un análisis de criticidad de las palas y los constantes problemas que conllevan a la no disponibilidad de estas, logrando identificar una deficiente gestión en el mantenimiento. Por tal motivo, se propuso el desarrollo para implementación del TPM, que consiste en aplicar los pilares de educación y entrenamiento a los operadores, mantenimiento planificado y seguridad y medio ambiente, además de la implementación de las 5S. Finalmente, se procedió a realizar una simulación de lo propuesto en el software arena y comparando los resultados antes y después de la implementación del TPM obteniendo así un incremento de la disponibilidad del 4.2 % aproximadamente en las palas, gracias a las mejoras propuestas en la gestión del mantenimiento. / By observing and analyzing the data collected in 2020 in the maintenance area of a mining company located in southern Peru, it was possible to identify the reasons for the low availability of the shovels within the productive loading process. That is why a criticality analysis was developed of the shovels and the constant problems that lead to their unavailability, managing to identify a poor maintenance management. For this reason, the development for the implementation of the TPM was proposed, which consists of applying the pillars of education and training to operators, planned maintenance and safety and environment, in addition to the implementation of the 5S. Finally, a simulation of what was proposed in the arena software was carried out and the results were compared before and after the implementation of the TPM, thus obtaining an increase in availability of approximately 4.2 % in the blades, thanks to the proposed improvements in the maintenance management. / Tesis

The pulp and paper industry is the most energy intensive industry in Sweden. Most of the energy usedaims to supply the large amount of heat to the production processes that is required to produce pulp andpaper . By increasing the energy efficiency of paper mills, there is great potential to reduce productioncosts and reduce its environmental impact. This project involves mapping, analyzing and investigation ofmeasures that can contribute to increased thermal efficiency of an internal heating network at Holmen’spaper mill, Braviken. The heating network, called VVG, utilises excess heat from the pulp and paperproduction and supplies heat to production processes and premises at the factory. When the heat demandof the VVG-system exceeds the available recovered heat, heat from live steam is transferred. This projectaim at identifying measures with potential to reduce demand of live steam supply. The project started bymapping the entire VVG-system to identify which consumers are included and how it is connected. Thenthe consumers were studied and data was collected to determine their power and energy demands. Basedon the mapping and collected data, proposals for measures that have the potential to increase thermalenergy efficiency were noted which in turn can reduce the need for live steam supply. The measures havebeen focused on reducing the return temperature of the VVG-system and reducing the heat demand of thesystem. Reduced return temperatures are achieved by more efficient use of the existing heat flow. Thisleads to increased heat recovery potential which means that more excess heat can be utilised.The proposed measures that were identified as having potential to contribute to reduction of the returntemperatures of the VVG-system are as follow: • Utilising return flows with high flow rates and high temperatures to provide other consumers inVVG with heat. This allows the hot flow to be used instead of going directly into the return line. • Eliminate short circuits in the system where the supply line goes directly into the return line. Thesewere detected in the forms of three-way valves and flows through consumers that were not running. The proposed measures that have been identified as having the potential to contribute to reduction of theheating demand of the VVG are as follows: • Turning off flows passing through consumers that are not in use to reduce unnecessary temperaturedrops which will result in decreased power losses. • Preheating via residual flows at consumers where raw water tempered circuits is heated. As theraw water is cold during large parts of the year, a lot of heat can be saved by preheating it with aflow of lower energy quality than VVG. • Shut down the VVG flow through heat exchangers in the heat recovery system when the heatrecovery process not are running to avoid negative heat transfer. By implementing these measures, large improvements regarding the thermal efficiency of the VVG-system can be achieved at Holmen Paper Braviken. How much the return temperatures decrease and howmuch the heat recovery potential increases with the proposed measures has not been quantified during thisproject. However, the measures aimed at lowering the heat demand in the VVG-system can be quantifiedto contribute to an predicted energy saving of at least 2.8 GWh annually, but the investigations of themeasures indicates that significantly larger energy savings can be achieved. To ensure the potential of theproposed measures to contribute to the reduction of the demand for live steam supply, Holmen needs tocarry out further studies of the VVG system where this work is intended to form the basis for their furtherwork.

This dissertation reports on research related to ultrafiltration (UF) membranes in drinking water applications. A pilot-scale investigation identified seasonal surface water quality impacts on UF performance and resulted in the development of a dynamic chemically enhanced backwash protocol for fouling management. Subsequent analysis of UF process data revealed limitations with the use of specific flux, transmembrane pressure (TMP), and other normalization techniques for assessing UF process fouling. A new TMP balance approach is presented that identifies the pressure contribution of membrane fouling and structural changes, enables direct process performance comparisons at different operating fluxes, and distinguishes between physically and chemically unresolved fouling. In addition to the TMP balance, a five component optimization approach is presented for the systematic improvement of UF processes on the basis of TMP variations. Terms are defined for assessing process event performance, a new process utilization term is presented to benchmark UF productivity, and new measures for evaluating maintenance procedures are discussed. Using these tools, a correlation between process utilization and operating pressures was established and a sustainable process utilization of 93.5% was achieved. UF process capabilities may be further enhanced by pre-coating media onto the membrane surface. Silicon dioxide (SiO2) and powdered activated carbon (PAC) are evaluated as precoating materials, and the applicability of the TMP balance for assessing pre-coated membrane performance is demonstrated. The first use of SiO2 as a support layer for PAC in a membrane pre-coating application is presented at the laboratory-scale. SiO2-PAC pre-coatings successfully reduced physically unresolved fouling and enhanced UF membrane organics removal capabilities.

Cyber-physical systems are dynamic physical systems that are controlled by computers for their safe and sound operations (e.g., cars, satellites, robots, elevators, and many others). Consequently, the programs running cyber-physical systems have real-time requirements, which require the programs to compute not only correctly but also timely because dynamic physical systems need to move to correct positions within certain duration to ensure safe and sound operations. To satisfy real-time requirements in better ways, many real-time languages have been proposed in the literature. Nevertheless, the general-purpose non-real-time languages C and C++ have remained the de facto languages to program cyber-physical systems, including Mars rovers and F-35 jet fighters. Given this reality, the better ways to satisfy real-time requirements have been the use of model-based tools (e.g., MATLAB/Simulink) that allow cyber-physical systems to be designed by modeling and simulating them and the resulting models to be translated automatically to C programs. Model-based tools, however, leave the resulting C programs for manual integration with other C/C++ programs, such as legacy/third-party device drivers and libraries. Since manual integration could slip in some inconsistencies, which proved fatal in the maiden flight of Ariane-5 rocket, this work shows how the standard features of C++, which support active libraries, can be used to embed a model-based real-time language, called Tice, as a C++ active library that can be used to declaratively express models of real-time systems that are processable by off-the-shelf standard C++ compilers (e.g., GCC and Clang) that automatically not only translate the models into C/C++ programs but also check both the validity of the models and the consistency of the models with other C/C++ programs. Furthermore, being compilable by off-the-shelf standard C++ compilers also sets Tice apart from other real-time languages already proposed in the literature because the other languages require either their own special compilers/interpreters or non-standard C/C++ compilers. Consequently, while Tice itself either uses no C++ features that are unsuitable for cyber-physical systems (e.g., exception) or uses some in judicious manner (e.g., template instantiations to generate programs), Tice prevents no usage that is permitted by standard C++ compilers. Beside that, as C++ active libraries are indeed ordinary C++ libraries, C++ active libraries are seamlessly composable as ordinary C++ libraries, and therefore, as models play an increasingly important role in software engineering, this work shows the potential of C++ as a platform for language-oriented programming where different languages that express different kinds of models and are embedded as C++ active libraries could be composed seamlessly.

<p>The potential of using acid hydrogen peroxide under Fenton conditions to lower the electrical energy consumed during the production of Black spruce (Picea mariana) thermomechanical pulp (TMP) was investigated. The chemical system, which consisted of ferrous sulphate, hydrogen peroxide and optionally an enhancer (3,4-dimethoxybenzyl alcohol, ethylenediaminetetraacetic acid or oxalic acid/sodium oxalate), was evaluated as an inter-stage treatment where the primary refiner was used as a mixer. The produced TMPs were thoroughly characterised in order to explain the effect of the chemical system on fibre development and to be able to propose a mechanism for the impact on refining energy reduction. The possibility to improve the optical properties by washing, chelating and sodium dithionite or hydrogen peroxide bleaching the treated pulps was evaluated.</p><p> </p><p>The results obtained in a pilot plant trial show that it is possible to significantly reduce the comparative specific energy consumption by approximately 20% and 35% at a freeness value of 100 ml CSF or a tensile index of 45 Nm/g by using 1% and 2% hydrogen peroxide respectively. The energy reduction is obtained without any substantial change in the fractional composition of the pulp, though tear strength is slightly reduced, as are brightness and pulp yield. No major differences between the reference pulp and the chemically treated pulps were found with respect to fibre length, width or cross-sectional dimensions. However, the acid hydrogen peroxide-treated pulps tend to have more collapsed fibres, higher flexibility, a larger specific surface area and a lower coarseness value. The yield loss accompanying the treatment is mainly a consequence of degraded hemicelluloses. It was also found that the total charge of the chemically treated pulps is higher compared to the reference pulps, something that may have influenced the softening behaviour of the fibre wall.</p><p> </p><p>A washing or chelating procedure can reduce the metal ion content of the chemically treated TMPs considerably. The amount of iron can be further reduced to a level similar to that of untreated pulps by performing a reducing agent-assisted chelating stage (QY) with dithionite. The discoloration cannot, however, be completely eliminated. The brightness decrease of the treated pulps is thus not only caused by higher iron content in the pulp, but is also dependent on the type of iron compound and/or other coloured compounds connected with the acid hydrogen peroxide treatment. Oxidative bleaching with hydrogen peroxide (P) is more effective than reductive bleaching with sodium dithionite in regaining the brightness lost during the energy reductive treatment. Using a QY P sequence, a hydrogen peroxide charge of 3.8% was needed to reach an ISO brightness of 75% for the chemically treated pulps. The corresponding hydrogen peroxide charge for the untreated TMP reference was 2.5%.</p><p> </p><p>The radicals generated in the Fenton reaction will probably attack and weaken/soften the available outer fibre wall layers. This could facilitate fibre development and consequently lower the electrical energy demand for a certain degree of refinement.</p>

The potential of using acid hydrogen peroxide under Fenton conditions to lower the electrical energy consumed during the production of Black spruce (Picea mariana) thermomechanical pulp (TMP) was investigated. The chemical system, which consisted of ferrous sulphate, hydrogen peroxide and optionally an enhancer (3,4-dimethoxybenzyl alcohol, ethylenediaminetetraacetic acid or oxalic acid/sodium oxalate), was evaluated as an inter-stage treatment where the primary refiner was used as a mixer. The produced TMPs were thoroughly characterised in order to explain the effect of the chemical system on fibre development and to be able to propose a mechanism for the impact on refining energy reduction. The possibility to improve the optical properties by washing, chelating and sodium dithionite or hydrogen peroxide bleaching the treated pulps was evaluated.   The results obtained in a pilot plant trial show that it is possible to significantly reduce the comparative specific energy consumption by approximately 20% and 35% at a freeness value of 100 ml CSF or a tensile index of 45 Nm/g by using 1% and 2% hydrogen peroxide respectively. The energy reduction is obtained without any substantial change in the fractional composition of the pulp, though tear strength is slightly reduced, as are brightness and pulp yield. No major differences between the reference pulp and the chemically treated pulps were found with respect to fibre length, width or cross-sectional dimensions. However, the acid hydrogen peroxide-treated pulps tend to have more collapsed fibres, higher flexibility, a larger specific surface area and a lower coarseness value. The yield loss accompanying the treatment is mainly a consequence of degraded hemicelluloses. It was also found that the total charge of the chemically treated pulps is higher compared to the reference pulps, something that may have influenced the softening behaviour of the fibre wall.   A washing or chelating procedure can reduce the metal ion content of the chemically treated TMPs considerably. The amount of iron can be further reduced to a level similar to that of untreated pulps by performing a reducing agent-assisted chelating stage (QY) with dithionite. The discoloration cannot, however, be completely eliminated. The brightness decrease of the treated pulps is thus not only caused by higher iron content in the pulp, but is also dependent on the type of iron compound and/or other coloured compounds connected with the acid hydrogen peroxide treatment. Oxidative bleaching with hydrogen peroxide (P) is more effective than reductive bleaching with sodium dithionite in regaining the brightness lost during the energy reductive treatment. Using a QY P sequence, a hydrogen peroxide charge of 3.8% was needed to reach an ISO brightness of 75% for the chemically treated pulps. The corresponding hydrogen peroxide charge for the untreated TMP reference was 2.5%.   The radicals generated in the Fenton reaction will probably attack and weaken/soften the available outer fibre wall layers. This could facilitate fibre development and consequently lower the electrical energy demand for a certain degree of refinement.