994 resultados para product concept


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Asymmetric synthesis using modified heterogeneous catalysts has gained lots of interest in the production of optically pure chemicals, such as pharmaceuticals, nutraceuticals, fragrances and agrochemicals. Heterogeneous modified catalysts capable of inducing high enantioselectivities are preferred in industrial scale due to their superior separation and handling properties. The topic has been intensively investigated both in industry and academia. The enantioselective hydrogenation of ethyl benzoylformate (EBF) to (R)-ethyl mandelate over (-)-cinchonidine (CD)-modified Pt/Al2O3 catalyst in a laboratory-scale semi-batch reactor was studied as a function of modifier concentration, reaction temperature, stirring rate and catalyst particle size. The main product was always (R)-ethyl mandelate while small amounts of (S)-ethyl mandelate were obtained as by product. The kinetic results showed higher enantioselectivity and lower initial rates approaching asymptotically to a constant value as the amount of modifier was increased. Additionally, catalyst deactivation due to presence of impurities in the feed was prominent in some cases; therefore activated carbon was used as a cleaning agent of the raw material to remove impurities prior to catalyst addition. Detailed characterizations methods (SEM, EDX, TPR, BET, chemisorption, particle size distribution) of the catalysts were carried out. Solvent effects were also studied in the semi-batch reactor. Solvents with dielectric constant (e) between 2 and 25 were applied. The enantiomeric excess (ee) increased with an increase of the dielectric coefficient up to a maximum followed by a nonlinear decrease. A kinetic model was proposed for the enantioselectivity dependence on the dielectric constant based on the Kirkwood treatment. The non-linear dependence of ee on (e) successfully described the variation of ee in different solvents. Systematic kinetic experiments were carried out in the semi-batch reactor. Toluene was used as a solvent. Based on these results, a kinetic model based on the assumption of different number of sites was developed. Density functional theory calculations were applied to study the energetics of the EBF adsorption on pure Pt(1 1 1). The hydrogenation rate constants were determined along with the adsorption parameters by non-linear regression analysis. A comparison between the model and the experimental data revealed a very good correspondence. Transient experiments in a fixed-bed reactor were also carried out in this work. The results demonstrated that continuous enantioselective hydrogenation of EBF in hexane/2-propanol 90/10 (v/v) is possible and that continuous feeding of (-)-cinchonidine is needed to maintain a high steady-state enantioselectivity. The catalyst showed a good stability and high enantioselectivity was achieved in the fixed-bed reactor. Chromatographic separation of (R)- and (S)-ethyl mandelate originating from the continuous reactor was investigated. A commercial column filled with a chiral resin was chosen as a perspective preparative-scale adsorbent. Since the adsorption equilibrium isotherms were linear within the entire investigated range of concentrations, they were determined by pulse experiments for the isomers present in a post-reaction mixture. Breakthrough curves were measured and described successfully by the dispersive plug flow model with a linear driving force approximation. The focus of this research project was the development of a new integrated production concept of optically active chemicals by combining heterogeneous catalysis and chromatographic separation technology. The proposed work is fundamental research in advanced process technology aiming to improve efficiency and enable clean and environmentally benign production of enantiomeric pure chemicals.

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This study will concentrate on Product Data Management (PDM) systems, and sheet metal design features and classification. In this thesis, PDM is seen as an individual system which handles all product-related data and information. The meaning of relevant data is to take the manufacturing process further with fewer errors. The features of sheet metals are giving more information and value to the designed models. The possibility of implementing PDM and sheet metal features recognition are the core of this study. Their integration should make the design process faster and manufacturing-friendly products easier to design. The triangulation method is the basis for this research. The sections of this triangle are: scientific literature review, interview using the Delphi method and the author’s experience and observations. The main key findings of this study are: (1) the area of focus in triangle (the triangle of three different point of views: business, information exchange and technical) depends on the person’s background and their role in the company, (2) the classification in the PDM system (and also in the CAD system) should be done using the materials, tools and machines that are in use in the company and (3) the design process has to be more effective because of the increase of industrial production, sheet metal blank production and the designer’s time spent on actual design and (4) because Design For Manufacture (DFM) integration can be done with CAD-programs, DFM integration with the PDM system should also be possible.

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Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

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Työn tilaajana toimi Visedo Oy. Työn tavoitteina oli tutkia Visedo Oy:n ohjelmistokehityksen nykytila, tunnistaa seuraavat parannuskohteet ja antaa ohjeita havaittujen parannuskohteiden korjaamiseksi. Visedo Oy:n tehonmuokkain ohjelmistokehityksen nykytilaa käsiteltiin neljän valitun osa-alueen näkökulmasta: ohjelmistoarkkitehtuurityyli, komponenttipohjainen ohjelmistokehitys, ohjelmistotuotelinjojen kehitysmenetelmät ja ohjelmistovariaatioiden hallinta. Valituilla osa-alueilla havaittujen parannuskohteiden perusteella annettiin korjausehdotuksia: ohjelmistoarkkitehtuurin rakenteeseen, komponenttien jakautumiselle, komponenttien koostamiselle ja komponenttien versioinnille. Lisäksi ehdotettiin uudenlaista ohjelmistotuotelinja rakennetta, joka yhdistää kerros- ja komponenttipohjaiset arkkitehtuurityylit mahdollistaen ominaisuuksiltaan eroavien tehonmuokkain ohjelmistojen hallinnan.

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The master´s thesis had three aims; to develop a service portfolio, to support the management of services through the developed portfolio, and evaluate effects of service differentiation strategy on the future selection of services. The product oriented case company in service paradox is Hilti (Suomi) Oy, which is entering systematic service management era, supported by the late strategic change. Low return on service business investments is referred as service paradox. The project was carried out as a case study, where the primary information source was twenty-one conducted interviews. The theory part focuses on marketing logics, service strategies, and categorization of services. The empirical part contributes in solving the aim related research questions. As a result of the case study a service portfolio was created, next further steps in service management were suggested, and the effect on selection of services by service differentiation strategy was evaluated. The main goal of creating service portfolio contributes to systematic management of services, which required revising at the case company.

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Diplomityön tavoitteena oli tuottaa toimenpidesuunnitelma energiatehokkuuden parantamiseksi sekä tilannekatsaus tehtaan energiankäytöstä Saint-Gobain Raken-nustuotteet Oy:n Hyvinkään lasivillatehtaalla. Diplomityön ensisijaiseksi tutki-mustavoitteeksi asetettiin energiankäytön tehostamisen tutkiminen sekä energian-käytön analysointi ja jatkotoimenpidesuunnitelman laatiminen. Diplomityössä osoitettiin että lämmöntalteenotolla poistoilmasta voidaan saavut-taa 2000 MWh lämpöenergiansäästö. Yhteensä hyödynnettävää lämpöenergiaa selvitettiin syntyvän vuodessa 10 600 MWh. WCM- konseptilla, eli tuotannonte-hostamisohjelmalla pyritään energiankäytön systemaattiseen pienentämiseen. Täs-sä diplomityössä on esitetty energiankäytön tehostamisratkaisuja sekä energiate-hokkuuden liittämistä WCM- konseptiin. Diplomityön tuloksia voidaan hyödyntää järjestelmällisen energiatehokkuuden parantamisohjelman kehittämisessä sekä konkreettisten energiansäästötoimenpiteiden toteuttamisessa.

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Methyl chloride is an important chemical intermediate with a variety of applications. It is produced today in large units and shipped to the endusers. Most of the derived products are harmless, as silicones, butyl rubber and methyl cellulose. However, methyl chloride is highly toxic and flammable. On-site production in the required quantities is desirable to reduce the risks involved in transportation and storage. Ethyl chloride is a smaller-scale chemical intermediate that is mainly used in the production of cellulose derivatives. Thus, the combination of onsite production of methyl and ethyl chloride is attractive for the cellulose processing industry, e.g. current and future biorefineries. Both alkyl chlorides can be produced by hydrochlorination of the corresponding alcohol, ethanol or methanol. Microreactors are attractive for the on-site production as the reactions are very fast and involve toxic chemicals. In microreactors, the diffusion limitations can be suppressed and the process safety can be improved. The modular setup of microreactors is flexible to adjust the production capacity as needed. Although methyl and ethyl chloride are important chemical intermediates, the literature available on potential catalysts and reaction kinetics is limited. Thus the thesis includes an extensive catalyst screening and characterization, along with kinetic studies and engineering the hydrochlorination process in microreactors. A range of zeolite and alumina based catalysts, neat and impregnated with ZnCl2, were screened for the methanol hydrochlorination. The influence of zinc loading, support, zinc precursor and pH was investigated. The catalysts were characterized with FTIR, TEM, XPS, nitrogen physisorption, XRD and EDX to identify the relationship between the catalyst characteristics and the activity and selectivity in the methyl chloride synthesis. The acidic properties of the catalyst were strongly influenced upon the ZnCl2 modification. In both cases, alumina and zeolite supports, zinc reacted to a certain amount with specific surface sites, which resulted in a decrease of strong and medium Brønsted and Lewis acid sites and the formation of zinc-based weak Lewis acid sites. The latter are highly active and selective in methanol hydrochlorination. Along with the molecular zinc sites, bulk zinc species are present on the support material. Zinc modified zeolite catalysts exhibited the highest activity also at low temperatures (ca 200 °C), however, showing deactivation with time-onstream. Zn/H-ZSM-5 zeolite catalysts had a higher stability than ZnCl2 modified H-Beta and they could be regenerated by burning the coke in air at 400 °C. Neat alumina and zinc modified alumina catalysts were active and selective at 300 °C and higher temperatures. However, zeolite catalysts can be suitable for methyl chloride synthesis at lower temperatures, i.e. 200 °C. Neat γ-alumina was found to be the most stable catalyst when coated in a microreactor channel and it was thus used as the catalyst for systematic kinetic studies in the microreactor. A binder-free and reproducible catalyst coating technique was developed. The uniformity, thickness and stability of the coatings were extensively characterized by SEM, confocal microscopy and EDX analysis. A stable coating could be obtained by thermally pretreating the microreactor platelets and ball milling the alumina to obtain a small particle size. Slurry aging and slow drying improved the coating uniformity. Methyl chloride synthesis from methanol and hydrochloric acid was performed in an alumina-coated microreactor. Conversions from 4% to 83% were achieved in the investigated temperature range of 280-340 °C. This demonstrated that the reaction is fast enough to be successfully performed in a microreactor system. The performance of the microreactor was compared with a tubular fixed bed reactor. The results obtained with both reactors were comparable, but the microreactor allows a rapid catalytic screening with low consumption of chemicals. As a complete conversion of methanol could not be reached in a single microreactor, a second microreactor was coupled in series. A maximum conversion of 97.6 % and a selectivity of 98.8 % were reached at 340°C, which is close to the calculated values at a thermodynamic equilibrium. A kinetic model based on kinetic experiments and thermodynamic calculations was developed. The model was based on a Langmuir Hinshelwood-type mechanism and a plug flow model for the microreactor. The influence of the reactant adsorption on the catalyst surface was investigated by performing transient experiments and comparing different kinetic models. The obtained activation energy for methyl chloride was ca. two fold higher than the previously published, indicating diffusion limitations in the previous studies. A detailed modeling of the diffusion in the porous catalyst layer revealed that severe diffusion limitations occur starting from catalyst coating thicknesses of 50 μm. At a catalyst coating thickness of ca 15 μm as in the microreactor, the conditions of intrinsic kinetics prevail. Ethanol hydrochlorination was performed successfully in the microreactor system. The reaction temperature was 240-340°C. An almost complete conversion of ethanol was achieved at 340°C. The product distribution was broader than for methanol hydrochlorination. Ethylene, diethyl ether and acetaldehyde were detected as by-products, ethylene being the most dominant by-product. A kinetic model including a thorough thermodynamic analysis was developed and the influence of adsorbed HCl on the reaction rate of ethanol dehydration reactions was demonstrated. The separation of methyl chloride using condensers was investigated. The proposed microreactor-condenser concept enables the production of methyl chloride with a high purity of 99%.

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In this paper, the genus concept of Cheilolejeunea is discussed and revalued based upon the concept of the real position of the hyaline papilla, as well as upon the definition of apical tooth of the lobule in the genus.

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This master’s thesis was done for a small company, Vipetec Oy, which offers specialized technological services for companies mainly in forest industry. The study was initiated partly because the company wants to expand its customer base to a new industry. There were two goals connected to each other. First was to find out how much and what kind of value current customers have realized from ATA Process Event Library, one of the products that the company offers. Second was to determine the best way to present this value and its implications for future value potential to both current and potential customers. ATA helps to make grade and product changes, starting after machine downtime, and recovery from production break faster for customers. All three events sometimes occur in production line. The faster operation results to savings in time and material. In addition to ATA Vipetec also offers other services related to development of automation and optimization of controls. Theoretical part concentrates on the concept of value, how it can be delivered to customers, and what kind of risk customer faces in industrial purchasing. Also the function of reference marketing towards customers is discussed. In the empirical part the realized value for existing customers is evaluated based on both numerical data and interviews. There’s also a brief case study about one customer. After that the value-based reference marketing for a target industry is examined through interviews of these potential customers. Finally answers to the research questions are stated and compared also to the theoretical knowledge about the subject. Results show that those customers’ machines which use the full service concept of ATA usually are able to save more time and material than the machines which use only some features of the product. Interviews indicated that sales arguments which focus on improved competitive status are not as effective as current arguments which focus on numerical improvements. In the case of potential customers in the new industry, current sales arguments likely work best for those whose irregular production situations are caused mainly by fault situations. When the actions of Vipetec were compared to ten key elements of creating customer references, it was seen that many of them the company has either already included in its strategy or has good chances to include them with the help of the results of this study.

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Putkipalkkiliitosten käyttäminen offshore-teollisuuden rakennusten tukirakenteissa on erittäin yleistä. Liitosten valmistaminen on hankalaa ja hidasta. Hyvin usein tukirakenteiden putkipalkkiliitokset joudutaan hitsaamaan manuaalisesti tukirakenteen suuren koon vuoksi. Tukirakenteen uudella valmistustavalla, jossa rakenne kootaan pienemmistä osista, voidaan putkipalkkiliitosten valmistaminen ja hitsaaminen automatisoida. Robottihitsausasema sekä sen käyttöliittymä ja ohjelmisto todettiin toimivaksi ratkaisuksi putkipalkkiliitosten hitsaamiseen. Automaatiosuunnitteluun liittyy monia eri vaiheita, joiden huolellinen läpikäynti takaa todenmukaisemman konseptiratkaisun. Konseptiratkaisu kehittyy samalla, kun laitteistoja ja layoutia muokataan valmiimmiksi. Automaatiosuunnittelun aikana pyritään löytämään oikea taso automaatiolle. Valittu automaation taso vaikuttaa tuotannon tuottavuuteen, läpimenoaikaan ja joustavuuteen. Automaation määrällä vaikutetaan myös ihmisen tekemän työn määrään ja työnkuvaan. Tässä diplomityössä kehitettiin Pemamek Oy:lle hitsausautomaatioratkaisuja putkimaisille kappaleille. Putkiston osia valmistavan tehtaan hitsaus- ja tuotantoautomaation konseptiratkaisua tarkasteltiin esimerkkitapauksen muodossa, jolla kuvattiin, kuinka automaatiojärjestelmä voidaan suunnitella konseptitasolle. Toinen hitsausautomaatioratkaisu, joka tässä työssä kehitettiin, on robottihitsausasema käyttöliittymineen putkipalkkiliitoksen hitsaamiseen.

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A process for purifying bovine pancreatic glucagon as a by-product of insulin production is described. The glucagon-containing supernatant from the alkaline crystallization of insulin was precipitated using ammonium sulfate and isoelectric precipitation. The isoelectric precipitate containing glucagon was then purified by ion-exchange chromatography on Q-Sepharose FF, gel filtration on Sephadex G-25 and ion-exchange chromatography on S-Sepharose FF. A pilot scale test was performed with a recovery of 87.6% and a purification factor of 8.78 for the first chromatographic step, a recovery of 75.1% and a purification factor of 3.90 for the second, and a recovery of 76.2% and a purification factor of 2.36 for the last one. The overall yield was 50%, a purification factor of 80.8 was obtained and the fraction containing active glucagon (suitable for pharmaceutical preparations) was 84% pure as analyzed by HPLC

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A new concept termed "radioautographology" is advocated. This term was synthesized from "radioautography" and "ology", expressing a new science derived from radioautography. The concept of radioautographology (RAGology) is that of a science whose objective is to localize radioactive substances in the biological structure of objects and to analyze and study the significance of these substances in the biological structure. On the other hand, the old term radioautography (RAG) is the technique used to demonstrate the pattern of localization of various radiolabeled compounds in specimens. The specimens used in biology and medicine are cells and tissues. They are fixed, sectioned and placed in contact with the radioautographic emulsions, which are exposed and developed to produce metallic silver grains. Such specimens are designated as radioautographs and the patterns of pictures made of silver grains are named radioautograms. The technicians who produce radioautographs are named radioautographers, while those who study RAGology are scientists and should be called radioautographologists. The science of RAGology can be divided into two parts, general RAGology and special RAGology, as most natural sciences usually can. General RAGology is the technology of RAG which consists of three fields of science, i.e., physics concerning radioactivity, histochemistry for the treatment of cells and tissues, and photochemistry dealing with the photographic emulsions. Special RAGology, on the other hand, consists of applications of general RAGology. The applications can be classified into several scientific fields, i.e., cellular and molecular biology, anatomy, histology, embryology, pathology and pharmacology. Studies carried out in our laboratory are summarized and reviewed. All the results obtained from such applications should be systematized as a new field of science in the future.

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To evaluate the effect of exercise intensity on post-exercise cardiovascular responses, 12 young normotensive subjects performed in a randomized order three cycle ergometer exercise bouts of 45 min at 30, 50 and 80% of VO2peak, and 12 subjects rested for 45 min in a non-exercise control trial. Blood pressure (BP) and heart rate (HR) were measured for 20 min prior to exercise (baseline) and at intervals of 5 to 30 (R5-30), 35 to 60 (R35-60) and 65 to 90 (R65-90) min after exercise. Systolic, mean, and diastolic BP after exercise were significantly lower than baseline, and there was no difference between the three exercise intensities. After exercise at 30% of VO2peak, HR was significantly decreased at R35-60 and R65-90. In contrast, after exercise at 50 and 80% of VO2peak, HR was significantly increased at R5-30 and R35-60, respectively. Exercise at 30% of VO2peak significantly decreased rate pressure (RP) product (RP = HR x systolic BP) during the entire recovery period (baseline = 7930 ± 314 vs R5-30 = 7150 ± 326, R35-60 = 6794 ± 349, and R65-90 = 6628 ± 311, P<0.05), while exercise at 50% of VO2peak caused no change, and exercise at 80% of VO2peak produced a significant increase at R5-30 (7468 ± 267 vs 9818 ± 366, P<0.05) and no change at R35-60 or R65-90. Cardiovascular responses were not altered during the control trial. In conclusion, varying exercise intensity from 30 to 80% of VO2peak in young normotensive humans did not influence the magnitude of post-exercise hypotension. However, in contrast to exercise at 50 and 80% of VO2peak, exercise at 30% of VO2peak decreased post-exercise HR and RP.