Reaction Kinetics and Viscosity Modelling in the Fusion Syntheses of Ca- and Ca/Mg-resinates

Rosin is a natural product from pine forests and it is used as a raw material in resinate syntheses. Resinates are polyvalent metal salts of rosin acids and especially Ca- and Ca/Mg- resinates find wide application in the printing ink industry. In this thesis, analytical methods were applied to increase general knowledge of resinate chemistry and the reaction kinetics was studied in order to model the non linear solution viscosity increase during resinate syntheses by the fusion method. Solution viscosity in toluene is an important quality factor for resinates to be used in printing inks. The concept of critical resinate concentration, c crit, was introduced to define an abrupt change in viscosity dependence on resinate concentration in the solution. The concept was then used to explain the non-inear solution viscosity increase during resinate syntheses. A semi empirical model with two estimated parameters was derived for the viscosity increase on the basis of apparent reaction kinetics. The model was used to control the viscosity and to predict the total reaction time of the resinate process. The kinetic data from the complex reaction media was obtained by acid value titration and by FTIR spectroscopic analyses using a conventional calibration method to measure the resinate concentration and the concentration of free rosin acids. A multivariate calibration method was successfully applied to make partial least square (PLS) models for monitoring acid value and solution viscosity in both mid-infrared (MIR) and near infrared (NIR) regions during the syntheses. The calibration models can be used for on line resinate process monitoring. In kinetic studies, two main reaction steps were observed during the syntheses. First a fast irreversible resination reaction occurs at 235 °C and then a slow thermal decarboxylation of rosin acids starts to take place at 265 °C. Rosin oil is formed during the decarboxylation reaction step causing significant mass loss as the rosin oil evaporates from the system while the viscosity increases to the target level. The mass balance of the syntheses was determined based on the resinate concentration increase during the decarboxylation reaction step. A mechanistic study of the decarboxylation reaction was based on the observation that resinate molecules are partly solvated by rosin acids during the syntheses. Different decarboxylation mechanisms were proposed for the free and solvating rosin acids. The deduced kinetic model supported the analytical data of the syntheses in a wide resinate concentration region, over a wide range of viscosity values and at different reaction temperatures. In addition, the application of the kinetic model to the modified resinate syntheses gave a good fit. A novel synthesis method with the addition of decarboxylated rosin (i.e. rosin oil) to the reaction mixture was introduced. The conversion of rosin acid to resinate was increased to the level necessary to obtain the target viscosity for the product at 235 °C. Due to a lower reaction temperature than in traditional fusion synthesis at 265 °C, thermal decarboxylation is avoided. As a consequence, the mass yield of the resinate syntheses can be increased from ca. 70% to almost 100% by recycling the added rosin oil.

Cadeia do biodiesel da bancada à indústria: uma visão geral com prospecção de tarefas e oportunidades para P&D&I

Contextualized overview of the Biodiesel Production Chain, from the lab bench to the industry, with critical evaluation of state-of-art and technological development through scientific articles and patents, focusing on feedstock, reaction/production, first and second generation processes, specification and quality, transport, storage, co-products (effluents and sub-products), and emissions. Challenges are identified and solutions are proposed based on the Brazilian feedstock, edaphoclimatic conditions, process monitoring in remote regions, state policy, and environment preservation, among others. Forecasts are made based on the technology assessment, identifying future trends and opportunities for R&D&I.

Tietojärjestelmät palvelutuotannon tukena

Tämän tutkimuksen tavoitteena oli selvittää Imatran kaupungin teknisen toimen nykyinen tietojärjestelmäarkkitehtuuri, sekä selvittää, kuinka hyvin käytettävät tietojärjestelmät tukevat teknisen toimen tuottamaa omakotirakentajan palveluprosessia. Työn teoriaosassa syvennyttiin palvelujen hallintaan, tietojärjestelmiin ja paikkatietojärjestelmiin. Työn empiirisessä osassa tutkittiin, kuinka toimiva käytössä oleva järjestelmäkokonaisuus on. Tutkimus osoitti, että käytössä olevat tietojärjestelmät ja ohjelmistot ovat tehokkaita ja tarkoituksenmukaisia. Teknologian kehittämisen lisäksi tulee kiinnittää huomiota työskentelytapojen kehittämiseen ja yhtenäistämiseen esimerkiksi sähköisen prosessin seurantalomakkeen, tietokantojen päivittämisen, sekä paperisten aineistojen digitoimisen avulla. Tietojärjestelmäarkkitehtuurin tulee olla yksinkertainen ja päällekkäisiä toimintoja kannattaa välttää. Paikkatietojärjestelmien muuttaminen selainpohjaisiksi tehostaa eri tietolähteiden hyödyntämistä. Henkilöstön riittävä tietojärjestelmäkoulutus on tärkeää.

Täyteainepitoisuuden ja retentioainesysteemin optimointi

Työssä tutkittiin tarrapaperikoneen pohjapaperin täyteainepitoisuuden nostamisen vaikutusta koneen ajettavuuteen ja paperin ominaisuuksiin. Työn tavoitteena oli löytää ne prosessitekniset keinot, joilla voitaisiin saavuttaa raskaiden pintapapereiden tavoitetuhkatasot. Lisäksi pyrittiin optimoimaan retentioaineiden annokset ja ajotavat korkeilla tuhkatasoilla. Kirjallisuusosassa tarkasteltiin pinta- ja kolloidikemian perusteita sekä täyteainepitoisuuden vaikutusta paperin ominaisuuksiin ja prosessoitavuuteen. Lisäk-si syvennyttiin märänpään kemiaan selvittämällä mm. kalsiumkarbonaatin vesiliuoskemiaa ja erilaisten retentioaineiden ominaisuuksia ja niiden reaktiomekanismeja. Työn kokeellinen osa koostui kahdesta koeajosta. Ensimmäisessä koeajossa selvitettiin täyteainesaostumien muodostumismekanismeja ja paperikoneen ajettavuutta täyteainepitoisuutta nostettaessa yli raskaiden pintapapereiden tavoitetasojen. Saadut tulokset osoittivat, että märänpään kemiantila pysyi koeajon aikana muuttumattomana eikä mitään saostumien muodostumista havaittu. Täyteainepitoisuudessa päästiin 3 % yli lajikohtaisen tuhkatavoitteen ilman ajettavuusongelmia. Toisessa koeajossa keskityttiin erityisesti märänpään retentioaineiden määrien optimointiin ja paperin laatuominaisuuksiin. Koeajossa täyteainepitoisuutta nostettiin yli tavoitetasojen. Saadut tulokset osoittivat, että täyteainepitoisuuden nostolla ei ollut vaikutusta paperin laatuun tai paperikoneen ajettavuuteen. Massatärkkelyksen avulla pystyttiin korvaamaan kationisen polymeerin retentiovaste ja kompensoimaan täyteainepitoisuuden noston myötä tullut paperin lujuuksien lasku. Koeajoissa ja prosessin seurannassa tuli ilmi myös useita eri tekijöitä, joilla oli vaikutusta retentioon, retentioaineiden tehoon ja prosessin stabiilisuuteen. Tehdyistä yksittäisistä havainnoista on hyötyä pyrittäessä ymmärtämään märänpään prosessin tilaa ja sen vaikutusta paperikoneen ajettavuuteen. Työ saavutti sille asetetut tavoitteet ja sen ansiosta paperikoneen märänpään raaka-aineiden ja kemikaalien syöttösuhteita pystyttiin muuttamaan tavalla, joka vähensi paperinvalmistuksen kustannuksia ilman että paperin laatuominaisuudet huononivat.

Modelling Cutting States in Rough Turning of 34CrNiMo6 Steel

Rough turning is an important form of manufacturing cylinder-symmetric parts. Thus far, increasing the level of automation in rough turning has included process monitoring methods or adaptive turning control methods that aim to keep the process conditions constant. However, in order to improve process safety, quality and efficiency, an adaptive turning control should be transformed into an intelligent machining system optimizing cutting values to match process conditions or to actively seek to improve process conditions. In this study, primary and secondary chatter and chip formation are studied to understand how to measure the effect of these phenomena to the process conditions and how to avoid undesired cutting conditions. The concept of cutting state is used to address the combination of these phenomena and the current use of the power capacity of the lathe. The measures to the phenomena are not developed based on physical measures, but instead, the severity of the measures is modelled against expert opinion. Based on the concept of cutting state, an expert system style fuzzy control system capable of optimizing the cutting process was created. Important aspects of the system include the capability to adapt to several cutting phenomena appearing at once, even if the said phenomena would potentially require conflicting control action.

Capillary electrophoresis: Applicability and method validation for biorefinery analytics

Wood-based bioprocesses present one of the fields of interest with the most potential in the circular economy. Expanding the use of wood raw material in sustainable industrial processes is acknowledged on both a global and a regional scale. This thesis concerns the application of a capillary zone electrophoresis (CZE) method with the aim of monitoring wood-based bioprocesses. The range of detectable carbohydrate compounds is expanded to furfural and polydatin in aquatic matrices. The experimental portion has been conducted on a laboratory scale with samples imitating process samples. This thesis presents a novel strategy for the uncertainty evaluation via in-house validation. The focus of the work is on the uncertainty factors of the CZE method. The CZE equipment is sensitive to ambient conditions. Therefore, a proper validation is essential for robust application. This thesis introduces a tool for process monitoring of modern bioprocesses. As a result, it is concluded that the applied CZE method provides additional results to the analysed samples and that the profiling approach is suitable for detecting changes in process samples. The CZE method shows significant potential in process monitoring because of the capability of simultaneously detecting carbohydrate-related compound clusters. The clusters can be used as summary terms, indicating process variation and drift.

Incident-Reporting-Systeme als Möglichkeit zum organisationalem Lernen (nicht nur) aus Fehlern und kritischen Ereignissen

Die vorliegende Dissertation betrachtet institutionsinterne lokale (Critical-)Incident-Reporting-Systeme ((C)IRS) als eine Möglichkeit zum Lernen aus Fehlern und unerwünschten kritischen Ereignissen (sogenannte Incidents) im Krankenhaus. Die Notwendigkeit aus Incidents zu lernen, wird im Gesundheitswesen bereits seit den 1990er Jahren verstärkt diskutiert. Insbesondere risikoreichen Organisationen, in denen Incidents fatale Konsequenzen haben können, sollten umfassende Strategien erarbeiten, die sie vor Fehlern und unerwünschten Ereignissen schützen und diese als Lernpotenzial nutzen können. Dabei können lokale IRS als ein zentraler Bestandteil des Risikomanagements und freiwillige Dokumentationssysteme im Krankenhaus ein Teil dieser Strategie sein. Sie können eine Ausgangslage für die systematische Erfassung und Auswertung von individuellen Lerngelegenheiten und den Transfer zurück in die Organisation schaffen. Hierfür sind eine lernförderliche Gestaltung, Implementierung und Einbettung lokaler IRS eine wichtige Voraussetzung. Untersuchungen über geeignete lerntheoretisch fundierte und wirkungsvolle IRS-Modelle und empirische Daten fehlen bisher im deutschsprachigen Raum. Einen entsprechenden Beitrag leistet die vorliegende Fallstudie in einem Schweizer Universitätsspital (800 Betten, 6.100 Mitarbeitende). Zu diesem Zweck wurde zuerst ein Anforderungsprofil an lernförderliche IRS aus der Literatur abgeleitet. Dieses berücksichtigt zum einen literaturbasierte Kriterien für die Gestaltung und Nutzung aus der IRS-Literatur, zum anderen die aus der Erziehungswissenschaft und Arbeitspsychologie entlehnten Gestaltungsbedingungen und Erfolgskriterien an organisationales Lernen. Das Anforderungsprofil wurde in drei empirischen Teilstudien validiert und entsprechend adaptiert. In der ersten empirischen Teilstudie erfolgte eine Standortbestimmung der lokalen IRS. Die Erhebung erfolgte in vier Kliniken mittels Dokumentenanalyse, leitfadengestützter Interviews (N=18), sieben strukturierter Gruppendiskussionen und teilnehmender Beobachtungen über einen Zeitraum von 22 Monaten. Erfolgskritische IRS-Merkmale wurden identifiziert mit dem Ziel einer praxisgerechten lernförderlichen Systemgestaltung und Umsetzung von Incident Reporting unter Betrachtung von organisationalen Rahmenbedingungen, Lernpotenzialen und Barrieren. Die zweite Teilstudie untersuchte zwei Fallbeispiele organisationalen Lernens mittels Prozessbegleitung, welche zu einem verwechslungssicheren Design bei einem Medizinalprodukt und einer verbesserten Patientenidentifikation in Zusammenhang mit Blutentnahmen führten. Für das organisationale Lernen im Spital wurden dabei Chancen, Barrieren und Gestaltungsansätze abgeleitet, wie erwünschte Veränderungen und Lernen unter Nutzung von IRS initiiert werden können und dabei ein besseres Gesundheitsresultat erreicht werden kann. Die dritte Teilstudie überprüfte, inwiefern die Nutzung und Implementierung lokaler IRS mittels einer Mitarbeitervollbefragung zur Sicherheitskultur gefördert werden kann. Hierfür wurde eine positive Interaktion, zwischen einer starken Sicherheitskultur und der Bereitschaft ein IRS zu implementieren und Incidents zu berichten, angenommen. Zum Einsatz kam eine deutschsprachige Version des Hospital Survey on Patient Safety Culture (Patientensicherheitsklimainventar) mit einem Rücklauf von 46.8% (2.897 gültige Fragebogen). In 23 von 37 Kliniken führte laut einer Nachbefragung die Sicherheitskulturbefragung zum Implementierungsentscheid. Dies konnte durch Monitoring der IRS-Nutzung bestätigt werden. Erstmals liegen mit diesen Studien empirische Daten für eine wirkungsvolle und lernförderliche Gestaltung und Umsetzung von lokalen IRS am Beispiel einer Schweizer Gesundheitsorganisation vor. Die Ergebnisse der Arbeit zeigen Chancen und Barrieren für IRS als Berichts- und Lernsysteme im Krankenhaus auf. Als Resultat unsachgemäss gestalteter und implementierter IRS konnte dabei vor allem Lernverhinderung infolge IRS aufgezeigt werden. Blinder Aktionismus und eine fehlende Priorisierung von Patientensicherheit, unzureichende Kompetenzen, Qualifikationen und Ressourcen führten dabei zur Schaffung neuer Fehlerquellen mit einer Verstärkung des Lernens erster Ordnung. Eine lernförderliche Gestaltung und Unterhaltung der lokalen IRS, eingebettet in eine klinikumsweite Qualitäts- und Patientensicherheitsstrategie, erwiesen sich hingegen als wirkungsvoll im Sinne eines organisationalen Lernens und eines kontinuierlichen Verbesserungsprozesses. Patientensicherheitskulturbefragungen erwiesen sich zudem bei entsprechender Einbettung als effektives Instrument, um die Implementierung von IRS zu fördern. Zwölf Thesen zeigen in verdichteter Form auf, welche Gestaltungsprinzipien für IRS als Instrument des organisationalen Lernens im Rahmen des klinischen Risikomanagements und zur Förderung einer starken Patientensicherheitskultur zu berücksichtigen sind. Die Erkenntnisse aus den empirischen Studien münden in ein dialogorientiertes Rahmenmodell organisationalen Lernens unter Nutzung lokaler IRS. Die Arbeit zeigt damit zum einen Möglichkeiten für ein Lernen auf den verschiedenen Ebenen der Organisation auf und weist auf die Notwendigkeit einer (Re-)Strukturierung der aktuellen IRS-Diskussion hin.

Interacting software-agents to support a kind of expert supervision systems

Expert supervision systems are software applications specially designed to automate process monitoring. The goal is to reduce the dependency on human operators to assure the correct operation of a process including faulty situations. Construction of this kind of application involves an important task of design and development in order to represent and to manipulate process data and behaviour at different degrees of abstraction for interfacing with data acquisition systems connected to the process. This is an open problem that becomes more complex with the number of variables, parameters and relations to account for the complexity of the process. Multiple specialised modules tuned to solve simpler tasks that operate under a co-ordination provide a solution. A modular architecture based on concepts of software agents, taking advantage of the integration of diverse knowledge-based techniques, is proposed for this purpose. The components (software agents, communication mechanisms and perception/action mechanisms) are based on ICa (Intelligent Control architecture), software middleware supporting the build-up of applications with software agent features

Application of near and mid-infrared spectroscopy to determine cheese quality and authenticity

This paper reviews the current state of development of both near-infrared (NIR) and mid-infrared (MIR) spectroscopic techniques for process monitoring, quality control, and authenticity determination in cheese processing. Infrared spectroscopy has been identified as an ideal process analytical technology tool, and recent publications have demonstrated the potential of both NIR and MIR spectroscopy, coupled with chemometric techniques, for monitoring coagulation, syneresis, and ripening as well as determination of authenticity, composition, sensory, and rheological parameters. Recent research is reviewed and compared on the basis of experimental design, spectroscopic and chemometric methods employed to assess the potential of infrared spectroscopy as a technology for improving process control and quality in cheese manufacture. Emerging research areas for these technologies, such as cheese authenticity and food chain traceability, are also discussed.

Estratégias para elaboração de um plano de segurança da água para abastecimento humano do município do Natal/RN

This research study deals with the production and distribution of drinking water with quality and safety in order to meet the needs of the Man. Points out the limitations of the methodology for assessing water quality in use today. Approaches the recommendations of the World Health Organization (WHO) for adoption, by the companies responsible for producing and distributing water, of assessment methodologies and risk management (HACCP), in order to ensure the quality and safety of water drinking. Suggests strategies for implementing the plan for water safety plan. Uses the process of water production, composed by Maxaranguape river basin, the water treatment plant and distribution system, which is part of the Plan for Expansion of the Supply System of Natal, as case study. The results, it was possible to devise strategies for implementation of the Water Safety Plan (WSP), which comprises the following steps: a) a preliminary stage. b) assessment system. c) process monitoring. d) management plan and e) validation and verification of the PSA. At each stage are included actions for its implementation. The implementation of the PSA shows a new type of water production, in which the fountain as a whole (watershed and point of capture), the Water Treatment Plant (WTP) and distribution, shall compose the production process, over which to build quality and safety of the final product (drinking water)

A complexa fisiopatologia dos episódios vasooclusivos na anemia falciforme

Hemolytic anemia and vasoocclusion are the cardinal clinical features of sickle cell anemia. Vasoocclusion is a complex process involving not only the polymerization of deoxygenated sickle hemoglobin tetramers, but also interactions between sickle erythrocytes, vascular endothelium, platelets, leukocytes, and plasma proteins. The increased adherence of sickle erythrocytes to endothelium has been implicated as an early step in vasoocclusion. Other researchers have focused on leukocytes and platelets which might also contribute to disturbed blood flow. Microvascular occlusion results in acute painful crises, whereas macrovascular occlusion seems to be the cause of organ failure. The anemia results from the markedly shortened circulatory survival of sickle erythrocytes, together with a limited erythropoietic response. The erythropoiesis increases intensively, but it is not enough to balance the increased rate of erythrocytes destruction to maintain normal levels of total erythrocytes and hemoglobin concentrations; mainly by the low oxygen affinity of hemoglobin S and increased 2,3-Diphosphoglycerate. It is very difficult to separate processes leading to anemia or to vasoocclusion. Understanding the involvement of multiple blood componentes in vasoocclusion may elucidate the clinical manifestations and complications of sickle cell anemia, and may give new insights into the preventive and curative therapy.

Development of an instrumentation system embedded on FPGA for real time measurement of mechanical vibrations in rotating machinery

The real-time monitoring of events in an industrial plant is vital, to monitor the actual conditions of operation of the machinery responsible for the manufacturing process. A predictive maintenance program includes condition monitoring of the rotating machinery, to anticipate possible conditions of failure. To increase the operational reliability it is thus necessary an efficient tool to analyze and monitor the equipments, in real-time, and enabling the detection of e.g. incipient faults in bearings. To fulfill these requirements some innovations have become frequent, namely the inclusion of vibration sensors or stator current sensors. These innovations enable the development of new design methodologies that take into account the ease of future modifications, upgrades, and replacement of the monitored machine, as well as expansion of the monitoring system. This paper presents the development, implementation and testing of an instrument for vibration monitoring, as a possible solution to embed in industrial environment. The digital control system is based on an FPGA, and its configuration with an open hardware design tool is described. Special focus is given to the area of fault detection in rolling bearings. © 2012 IEEE.

Estimação do diâmetro e rugosidade em um processo de furação utilizando multi sensores e redes neurais artificiais

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estimação do diâmetro de furos em processo de furação utilizando sistemas de inteligência artificial: uma análise comparativa entre diferentes técnicas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Utilização de diferentes métodos de lubri-refrigeração na retificação cilíndrica externa de mergulho de cerâmica avançada com rebolo diamantado

Pós-graduação em Ciência e Tecnologia de Materiais - FC