The square shank tool holder is one of Sandvik Coromants most common products. The tool holder has been manufactured the same way for 25 years without changing tolerances. However, it is predicted that tighter tolerances will be required in the future to maintain competitiveness.   The purpose of the thesis was to study how today's square shank tool holders can be made straighter and to what price it can be done. The tolerances allow too much convexity and concavity which might lead to unstable products. To find where in the current production flow the greatest impact occurs, the production flow was studied and then a common square shank tool holder with high production volume was followed through the production flow.   The tool holders were measured with a CMM after each station and analysis showed that the hardening station has the largest impact on the tolerances. This lead to six experiments using different manufacturing methods and the results were compared to see what production flow that allowed the best tolerances and lowest cost.   The results lead to two optional ways of manufacturing since they showed better results with a production economic perspective. Option 1 includes manufacturing in hardened material and Option 2 includes a grinding process.   The production flow for Option 1 is to first harden the blank followed by the manufacturing processes. By moving the hardening processes to the beginning of the production flow, the shape changing is prevented and the final product becomes straighter and obtains a smooth and aesthetic surface since the hardening process creates a rough surface. The production time is increased by CON% and the production cost is increased by CON%. The bottom side flatness tolerance of the final product is reduced by CON%.   The production flow for Option 2 is to first manufacture the shank followed by hardening. After the hardening process the tools get surface grounded on the bottom side and the outside. By grinding the tool holder, it becomes straight and the surface flatness obtains a tolerance of CON mm. The production time is increased by CON% and the production cost is increased by CON%. The bottom surface flatness tolerance of the final product is reduced by CON%.   The advantages of Option 1 are that the final product becomes better and it is easy to apply in the current production flow. The advantages of Option 2 the surface becomes very flat and the tool holder is more competitive.   By choosing any of these two options, Sandvik Coromant will achieve a straighter and more competitive final product.

This thesis describes the development of high performing low-cost and low-power ammonia sensors on plastic substrates using solution processing techniques. As a part of the Marie Curie Initial Training Networks, FlexSmell project aimed at the realisation of such sensors as elements of a sensing system on flexible tags for wireless compatible applications. Ammonia was selected as the target analyte due to its importance in many application fields including food industry, air and water quality monitoring. Polyaniline, a conjugated polymer, was used as the sensing layer for chemiresistive detection of ammonia because of its well-known gas sensing properties. Two distinctive strategies were adapted to tackle doped polyaniline’s lack of solution processablity. Firstly, dopant engineering was utilised to prepare doped polyaniline formulations in aprotic solvents such as n-methyl-2-pyrrolidone. Hybrid composites were then prepared by simply mixing the polyaniline solutions and carbon nanoparticles. Sensors made by spin coating the polyaniline hybrid composites on plastic substrates operating at ~80 °C showed sensitivities more than 6 times higher than that of a commercial metal oxide sensor when exposed to sub-ppm concentrations of ammonia in air. The incompatibility of the multifunctional dopants used in this method with printed electronics, as well as the high boiling point and toxicity of the solvent led to the second approach. A two-step vapour-phase deposition polymerisation method was exploited to in-situ polymerise different polymeric acid-doped polyaniline thin films on plastic substrates. Polyaniline sensors doped with poly(4-styrenesulphonic acid), demonstrated sensitive response to sub-ppm concentrations of ammonia vapour under both dry and humid conditions. These sensors showed enhanced recovery and repeatability when operated at elevated temperatures. Moreover, room temperature ammonia sensors were realised using Nafion as the dopant. Finally, ammonia sensors were made on small (~1 mm^2) printed polymeric micro-hotplates using a vapour-phase deposited polyaniline sensing layer in order to allow reliable operation at ~95 °C with power consumptions as low as 35 mW. Such low-cost, low-power, sensitive and selective ammonia chemiresistors may be incorporated in smart RFID tags for food, air and water quality monitoring.

Det är vanligt att elever befinner sig på olika kunskapsnivåer i en undervisningsgrupp och för att ta reda på vilka nivåer de befinner sig på går det att tillämpa Processbarhetsteorin. Det är en teori utformad av Manfred Pienemann för att studera hur inlärare processar grammatiska strukturer. Uppsatsen är främst byggd på en kvalitativ ansats på grund av de kvalitativa analyserna men även på en kvantitativ ansats då elevernas texter som är analyserade har räknats i procent och presenterats i fördelningar med hjälp av tabeller. Den deltagande gruppen bestod av 15 elever i en förberedelseklass med blandade åldrar från årskurs 7-9. Analyserna baserades på Processbarhetsteorin enligt Flyman Mattssons och Håkanssons analysmodell (2010, s. 66-75). Resultaten visade att eleverna i undervisningsgruppen, vars texter analyserades, befann sig på olika PT-nivåer och det förekom även olika typer av grammatiska strukturer bland eleverna. Majoriteten av eleverna processade grammatiska strukturer för PT-nivå 2 och/eller PT-nivå 3 i uppgift 1 och/eller uppgift 2. De olika resultaten kan bero på faktorer såsom startålder för språkinlärning då alla elever kom till den svenska skolan vid olika tillfällen men den främsta slutsatsen kan vara att de flesta elever i skolan är på olika kunskapsnivåer eftersom det visade sig genom de olika resultaten hos eleverna.

The aim of this study was to investigate longitudinally how a child learner acquired verbal morpho-syntax in Japanese in a naturalistic second language (L2) context. Specifically the points of emergence for three verbal morpho-syntactic structures, namely verbal inflection, the V-te V structure and the passive/causative structure, were investigated within a framework of Processability Theory (PT) (Pienemann, 1998b). The subsequent development of these structures was also examined. Unlike earlier research about morpheme orders and developmental sequences in language acquisition which was criticised because of its apparent lack of theoretical underpinnings, Pienemann's Processability Theory (PT)(1998b) connects the processability of morpho-syntactic structure to linguistic theories. Pienemann also claims that this theory can be used to explain the acquisition of a wide range of morpho-syntactic structures and that it is typologically plausible and applicable to any language. In recent times PT has been extensively tested in a range of languages acquired as an L2, including German, English and Swedish (Pienemann, 1998b; Pienemann & Hakansson, 1999) and Italian and Japanese (Di Biase & Kawaguchi, 2002). The findings from these studies support this theory.

No description available.

Step-growth polymerization enabled the synthesis of novel polyester regioisomers and pendant functionalized polyetherimides (PEI)s. Novel monomers incorporated at targeted mol % produced series of polyesters and PEIs, suitable for systematic analysis of key polymer properties. Subsequent compositional, thermal, mechanical, and rheological characterization forged structure-property relationships to further understand the influence of composition on performance. Altering regiochemistry is a subtle way to maintain the same polymer composition but tune desired properties. Similarly, introducing functional pendant groups expands the property profile of common industrial polymers and installs a handle for secondary chemistry after synthesizing the main polymer. Both altering regiochemistry and adding pendant groups alters polymer properties without the need for large changes in synthetic requirements or reaction conditions, ideal for industrial adoption. Incorporation of a kinked bibenzoate (BB)-based diester monomers into the commonly utilized linear regioisomer afforded processable amorphous and semi-aromatic (co)polyesters. BB-(co)polyesters with ethylene glycol (EG) possessed improved barrier performance compared to poly(ethylene terephthalate) (PET) while improving on mechanical properties, including tensile and flexural modulus/strength, rivaling bisphenol-A polycarbonate (BPA-PC). Replacement of EG with 1,4-cyclohexanedimethanol (CHDM) improved thermal properties closer to BPA-PC, while enabling melt rheological analysis due to its amorphous morphology. Time-temperature superposition (TTS) analysis produced master curves provided insight into the entanglement molecular weight (Me) and entanglement density. More kinked structures possessed a lower Me and more entanglements. Introducing kinked monomers posed the question of cyclic speices generation during polymerization, common in step-growth reactions. Thus, systematic incorporation of meta-substituted hydroxyethylresorcinol and para-substituted hydroxyethylhydroquinone regioisomers into PET analogues enabled the characterization of cyclic formation due to monomer regioisomers. Increased meta substitution produced increased amounts of cylic species, analyzed by size exclusion chromatography (SEC). Adding functionality to high performance polyetherimides (PEI)s is difficult due to the high temperatures required for processing. The lack of thermal stability for commonly utilized H-bonding/reactive groups limits viable moieties. Utilizing the high temperture processing, PEIs incorporating pendant carboxylic acids reacted in the melt to form branched PEIs. These branched PEIs exhibited steeper shear thinning as well as improved flame resistance, limited in thin film commercial PEIs. / Doctor of Philosophy / My research focused on making new plastics (polymers) for use in consumer and performance markets. Typical applications utilizing these plastics include food packaging, consumer goods, automotive, aerospace, microelectronics, construction, and medical devices. Large changes such as intricate new chemicals used to make the plastics increase the difficulty in incorporating these new materials into existing synthesis and processing techniques and infrastructure. Thus, my research revolved around subtle changes to the chemical structure of the plastic, suitable for easy industrial adoption while also improving targeted properties necessary for the aforementioned applications. Polyesters are a class of polymers commonly used for food packaging and consumer goods. Thus, improving gas barrier performance and mechanical integrity/strength is crucial when designing new polyesters. Changing the bond angles through the linear versus kinked nature of the polymer chain imparts processability and improved gas barrier, compared to commercial poly(ethylene terepthalate) (PET), commonly used in food packaging applications. The density of the polyesters is also increased, which improves mechanical strength. The specific structures used also increased the thermal resistivity compared to PET. This higher thermal resistivity enables use in applications where high temperature cleaning such as steam sterilization and dish-washing could deform products or processing such as filling food packaging containers with hot foods. Similar types of polymers which possess much higher thermal resistivity are classified as high performance polymers. One class of these include polyetherimides (PEIs). The specific chemical structures and their high thermal resistance makes them great candidates for applications in automotive, aerospace, and microelectronic applications; although, these same properties make these polymers very difficult and expensive to process into the desired parts. Thus, adding functionality to the polymer by putting specific chemical groups off of the main chain enabled easier processing and improved other polymer properties. Adding the functionality to these polymers allowed them to react and change structure at high temperatures (during processing) to achieve a different shape, thus improving desired properties, such as how easy they flow like liquids at high temperatures and processing conditions. Another benefit realized from this change during processing was the improvement of flame resistance. Due to the chemical structure of the PEIs, they inherently possess resistance to catching on fire, remaining on fire, and dripping flaming material. Although PEIs typically possess good flame resistance, thin films or small parts made from these polymers do not possess the same flame resistance and can produce flaming drips, undesirable for applications requiring flame resistance. Chemically modifying these polymers with the aforementioned functionality and processing them increased the flame resistance to eliminate flaming drips and lessen the amount of time the polymer was on fire.

Polyacrylonitrile (PAN) and its copolymers are used in a wide variety of applications ranging from textiles to purification membranes, packaging material and carbon fiber precursors. High performance polyacrylonitrile copolymer fiber is the most dominant precursor for carbon fibers. Synthesis of very high molecular weight poly(acrylonitrile-co-methyl acrylate) copolymers with weight average molecular weights of at least 1.7 million g/mole were synthesized on a laboratory scale using low temperature, emulsion copolymerization in a closed pressure reactor. Single filaments were spun via hybrid dry-jet gel solution spinning. These very high molecular weight copolymers produced precursor fibers with tensile strengths averaging 954 MPa with an elastic modulus of 15.9 GPa (N = 296). The small filament diameters were approximately 5 'm. Results indicated that the low filament diameter that was achieved with a high draw ratio, combined with the hybrid dry-jet gel spinning process lead to an exponential enhancement of the tensile properties of these fibers. Carbon fibers for polymer matrix composites are currently derived from polyacrylonitrile copolymer fiber precursors where solution spinning accounts for ~40 % of the total fiber production cost. To expand carbon fiber applications into the automotive industry, the cost of the carbon fiber needs to be reduced from $8 to ~$3-5. In order to develop an alternative melt processing route several benign plasticizers have been investigated. A low temperature, persulfate-metabisulfite initiated emulsion copolymerization was developed to synthesize poly(acrylonitrile-co-methyl acrylate) copolymers with acrylonitrile contents between 91-96 wt% with a molecular weight range of 100-200 kg/mol. This method was designed for a potential industrial scale up. Furthermore, water was investigated as a potential melting point depressant for these copolymers. Twenty-five wt% water lead to a decrease in the Tm of a 93/7 wt/wt % poly(acrylonitrile-co-methyl acrylate) of Mw = 200 kg/mol to 160 0C as measured via DSC. Glycerin, ethylene glycol and glycerin/water combinations were investigated as potential plasticizers for high molecular weight (~200,000 g/mol), high acrylonitrile (93-96 mole:mole %) content poly(acrylonitrile–co-methyl acrylate) statistical copolymers. Pure glycerin (25 wt %) induced crystallization followed by a reduced "Tm" of about 213 °C via DSC. However this composition did not melt process well. A lower MW (~35 kg/mol) copolymer did extrude with no apparent degradation. Our hypothesis is that the hydroxyl groups in glycerin (or water) disrupt the strong dipole-dipole interactions between the chains enabling the copolymer endothermic transition (Tm) to be reduced and enable melting before the onset of degradation. Additionally high molecular weight (Mw = 200-230 kg/mol) poly(acrylonitrile–co-methyl acrylate) copolymers with lower acrylonitrile content (82-85 wt %) were synthesized via emulsion copolymerization and successfully melt pressed. These materials will be further investigated for their utility in packaging applications. / Ph. D.

This thesis is placed in the context of the ongoing debate on the issue whether second language acquisition occurs on the basis of innate language-specific learning mechanisms or general learning mechanisms. The author shares the view of scholars who propose that an innate knowledge base underlying first language acquisition does not extend to second language acquisition due to the lack of uniform success in the acquisition of native speaker competence, the possibility of fossilisation and the facilitative potential of form-focused instruction. It is, thus, assumed that the sequential second language acquisition process can be accounted for by general learning mechanisms. The key to these learning mechanisms is, firstly, the investigation of the nature of the knowledge underlying the grammatical encoding procedures for speech production in the context of M. Pienemann’s (1998a) Processability Theory and, secondly, the investigation of the nature of its acquisition process. Pienemann’s Processability Theory explains and predicts the sequential acquisition process of a second language as the result of the hierarchically ordered development of the processing procedures of the grammatical processor to grammatically encode conceptual information. It shares with Levelt’s (1989) theory of speech production the assumptions concerning the nature of the knowledge underlying the grammatical encoding procedures, which require further investigations for verification. Since the Processability Theory does not specify how the assumed knowledge underlying grammatical encoding is acquired, an investigation of the nature of its acquisition process is necessary. This investigation highlights the interdependence between the nature of the knowledge to be acquired and the nature of its acquisition process by demonstrating that the knowledge underlying grammatical encoding is predominantly implicit and, consequently, determines the implicit nature of its acquisition process. Such implicit knowledge is dissociated from explicit knowledge, which determines the explicit nature of its acquisition process. This investigation also demonstrates that explicit grammar teaching and practice in the context of the manipulation of the learners’ attentional orientation mediated by alertness may contribute to the implicit learning process under certain conditions. In conjunction with the provision of guidance by the Processability Theory in regard to the achievement of instructional focus and the independent finding that comprehensible input is needed in order for second language acquisition to occur, these results constitute the basis for the formulation of detailed instructional measures for the effective organisation of the sequential second language acquisition process. These measures are exemplified by their implementation for the initial stages of the acquisition of German as a second language. / PhD Doctorate

This dissertation examines the language proficiency of school-aged deaf pupils from a bilingual perspective. The first aim of the study is to investigate the Swedish L2 skills of the pupils. This includes testing the validity of the Processability Theory on deaf learners of Swedish as an L2. The second aim is to investigate whether there is a correlation between proficiency in Swedish and Swedish Sign Language (SSL) as suggested in earlier research on deaf bilingualism. This study is cross-sectional and contains data from 38 pupils (grades 5 and 10) from a school for deaf and hearing-impaired pupils in Sweden. The data consists of retellings of a cartoon in written Swedish and of free stories in SSL. For the first part of the study, the Swedish data has been analyzed according to Processability Theory (PT).  For the second part of the study, narrative structure in both the Swedish and SSL data has been analyzed. As a theoretical framework, Labov’s narrative model is applied. The results show that there is an implicational order in the informants’ development of Swedish following the predicted grammatical learning order described by PT. The results therefore suggest that PT is a valid theory also for deaf learners of L2 Swedish. The conclusions regarding SSL proficiency suggest that more research about sign language as such is needed to get a deeper understanding of SSL proficiency. The results show that one narrative component of Labov’s model - Evaluation - is an important component in SSL proficiency. The results from the comparative analysis show that there is a positive statistical correlation between some Swedish and SSL variables used in this study, suggesting that skills in Swedish correlate with skills in SSL. This means that a well-developed sign language is important for the deaf to learn any written language as a second language.

This study investigated the difficulty order of 38 grammar structures obtained from an analysis of multiple-choice items using a Rasch analysis. The order was compared with the order predicted by processability theory and the order in which the structures appear in junior and senior high school textbooks in Japan. Because processability theory is based on natural speech data, a sentence repetition test was also conducted in order to compare the result with the order obtained from the multiple-choice tests and the order predicted by processability theory. The participants were 872 Japanese university students, whose TOEIC scores ranged from 200 to 875. The difficulty order of the 38 structures was displayed according to their Rasch difficulty estimates: The most difficult structure was subjunctive and the easiest one was present perfect with since in the sentence. The order was not in accord with the order predicted by processability theory, and the difficulty order derived from the sentence repetition test was not accounted for by processability theory either. In other words, the results suggest that processability theory only accounts for natural speech data, and not elicited data. Although the order derived from the repetition test differed from the order derived from the written tests, they correlated strongly when the repetition test used ungrammatical sentences. This study tentatively concluded that the students could have used their implicit knowledge when answering the written tests, but it is also possible that students used their explicit knowledge when correcting ungrammatical sentences in the repetition test. The difficulty order of grammatical structures derived from this study was not in accord with the order in which the structures appear in junior and senior high school textbooks in Japan. Their correlation was extremely low, which suggests that there is no empirical basis for textbook makers'/writers' policy regarding the ordering of grammar items. This study also demonstrated the difficulty of writing items testing the knowledge of the same grammar point that show similar Rasch difficulty estimates. Even though the vocabulary and the sentence positions were carefully controlled and the two items looked parallel to teachers, they often displayed very different difficulty estimates. A questionnaire was administered concerning such items, and the students' responses suggested that they seemed to look at the items differently than teachers and what they notice and how they interpret what they notice strongly influences item difficulty. Teachers or test-writers should be aware that it is difficult to write items that produce similar difficulty estimates and their own intuition or experience might not be the best guide for writing effective grammar test items. It is recommended to pilot test items to get statistical information about item functioning and qualitative data from students using a think-aloud protocol, interviews, or a questionnaire. / CITE/Language Arts