Modelagem termodinâmica por extração por solvente de metais divalentes em meio sulfato usando D2EHPA

The extraction of divalent metals (Mn2+, Ni2+, Co2+ and Cu2+) in the system MSO4 - H2SO4 - H2O - D2EHPA in isoparaffin (17/21) was studied by a thermodynamic model based on chemical equilibria with mass and charge balance equations. The activity coefficients of all solutes in the aqueous phase were calculated by Davies equation. By applying this model, the equilibrium concentrations of solutes were calculated from de concentration of divalent metals and pH. The predicted distribution coefficients for the divalents metals were in good agreement with experimental results.

Identificação de extratos etanólicos de madeiras utilizando seu espectro eletrônico de absorção e análise multivariada

The application of multivariate analysis to spectrophotometric (UV) data was explored for distinguishing extracts of cachaça woods commonly used in the manufacture of casks for aging cachaças (oak, cabreúva-parda, jatobá, amendoim and canela-sassafrás). Absorbances close to 280 nm were more strongly correlated with oak and jatobá woods, whereas absorbances near 230 nm were more correlated with canela-sassafrás and cabreúva-parda. A comparison between the spectrophotometric model and the model based on chromatographic (HPLC-DAD) data was carried out. The spectrophotometric model better explained the variance data (PC1 + PC2 = 91%) exhibiting potential as a routine method for checking aged spirits.

Cinética e caracterização de ramnolipídeos produzidos por Pseudomonas aeruginosa MSIC02 utilizando glicerol como fonte de carbono

Glycerol, a co-product of biodiesel production, was used as a carbon source for the kinetics studies and production of biosurfactants by P. aeruginosa MSIC02. The highest fermentative parameters (Y PX = 3.04 g g-1; Y PS = 0.189 g g-1, P B = 31.94 mg L-1 h-1 and P X = 10.5 mg L-1 h-1) were obtained at concentrations of 0.4% (w/v) NaNO3 and 2% (w/v) glycerol. The rhamnolipid exhibited 80% of emulsification on kerosene, surface tension of 32.5 mN m-1, CMC = 28.2 mg L-1, C20 (concentration of surfactant in the bulk phase that produces a reduction of 20 dyn/cm in the surface tension of the solvent) = 0.99 mg L-1, Γm (surface concentration excess) = 2.4 x 10-26 mol Å-2 and S (surface area) = 70.4 Ų molecule-1 with solutions containing 10% NaCl. A mathematical model based on logistic equation was considered to representing the process. Model parameters were estimated by non-linear regression method. This approach was able to give a good description of the process.

INNOVATIVE USE OF A TABLET DEVICE TO DELIVER INSTRUCTION IN UNDERGRADUATE CHEMISTRY LECTURES

This report describes a simple, inexpensive and highly effective instructional model based on the use of a tablet device to enable the real-time projection of the instructor's digitally handwritten annotations to teach chemistry in undergraduate courses. The projection of digital handwriting allows the instructor to build, present and adapt the class contents in a dynamic fashion and to save anything that is annotated or displayed on the screen for subsequent sharing with students after each session. This method avoids the loss of continuity and information that often occurs when instructors switch between electronic slides and white/chalk board during lessons. Students acknowledged that this methodology allows them to follow the instructor's cognitive process and the progressive development of contents during lectures as the most valuable aspect of the implemented instructional model.

Varastojen hallinta projektiohjautuvassa toimintaympäristössä

Varastoihin sitoutuu yrityksissä paljon arvokasta pääomaa ja varastojen hallinnan osaaminen on noussut yhdeksi kilpailueduksi liiketoiminnassa. Varastoinnilla pyritään suojautumaan puutetilanteilta ja ylläpitämään haluttu palveluaste. Tutkielmassa selvitetään case yrityksen varastojen hallinnan nykytila ja nostetaan esille varastojen hallinnan ongelmatilanteet. Työn tavoitteena on muodostaa organisaation johdolle kokonaiskuva case yrityksen varastoista ja varastoinnin nykytilasta. Työ toteutetaan tapaustutkimuksena, ja aineisto kerätään organisaation henkilökunnasta valituille henkilöille suoritetuilla haastatteluilla. Haastatteluilla saadaan selville varastojen hallinnan toimintamallit ja toiminnan ongelmakohdat varastopaikkakunnilla. Työn tuloksena muodostetaan kokonaiskuva yrityksen varastotoiminnoista ja saadaan selville ongelmien taustalla olevat syyt. Ongelmien perusteella luodaan malli kehitystyön etenemiselle. Lopuksi työssä esitetään toimenpide- ehdotuksia varastojen hallinnan toimintojen jatkokehittämiseen.

Tietomallintamisen aiheuttamat muutokset ja hyödyt LVI-suunnitteluprosessissa sekä määrälaskennassa

Tässä diplomityössä tarkastellaan tietomallintamista eng. BIM (Building Information Modeling) LVI-suunnittelun näkökulmasta sekä esitellään tietomallintamisen vaikutuksia ja hyötyjä suunnitteluprosessiin. Tietomallintaminen mahdollistaa esimerkiksi LVI-suunnittelijan tuottaman määräluettelon 3D-mallista, jonka seurauksena eri toimijoiden väliset rajapinnat tulevat luultavasti kokemaan muutoksia. Työssä vertaillaan käsin laskettuja ja 3D-mallista tuotettuja määräluetteloita toisiinsa. Työhön sisällytetään myös urakoitsijoiden haastatteluja, joissa pyritään selvittämään heidän näkemyksiään suunnittelijan tuottamiin määrätietoihin.

Simulating the performance of paper machine control

The topic of this thesis is the simulation of a combination of several control and data assimilation methods, meant to be used for controlling the quality of paper in a paper machine. Paper making is a very complex process and the information obtained from the web is sparse. A paper web scanner can only measure a zig zag path on the web. An assimilation method is needed to process estimates for Machine Direction (MD) and Cross Direction (CD) profiles of the web. Quality control is based on these measurements. There is an increasing need for intelligent methods to assist in data assimilation. The target of this thesis is to study how such intelligent assimilation methods are affecting paper web quality. This work is based on a paper web simulator, which has been developed in the TEKES funded MASI NoTes project. The simulator is a valuable tool in comparing different assimilation methods. The thesis contains the comparison of four different assimilation methods. These data assimilation methods are a first order Bayesian model estimator, an ARMA model based on a higher order Bayesian estimator, a Fourier transform based Kalman filter estimator and a simple block estimator. The last one can be considered to be close to current operational methods. From these methods Bayesian, ARMA and Kalman all seem to have advantages over the commercial one. The Kalman and ARMA estimators seems to be best in overall performance.

Varastopalveluiden kustannuslaskentamallin rakentaminen

Tämän tutkimuksen tavoitteena oli rakentaa kustannuslaskentamalli, jota hyödynne-tään varastopalvelutoimintojen kustannusten tarkastelussa. Tavoitteena oli määrittää ”hintalaput” varaston eri toiminnoille eli selvittää minkä tyyppisiä resursseja toiminnot kuluttavat ja kuinka paljon. Lisäksi mallin tuloksien perusteella pyrittiin kartoittamaan tekijöitä joihin puuttumalla varastopalveluiden kustannustehokkuutta voitaisiin ke-hittää. Rakennettava laskentamalli perustui toimintolaskentaan. Tutkimus jakautui teoria- ja empiiriaosuuteen. Teoriaosuudessa käytiin läpi perinteistä kustannuslaskentaa ja toi-mintolaskentaa sekä verrattiin niitä keskenään. Teoriaosuudessa käytiin läpi myös toimintoperusteiden kustannuslaskentamallin rakentamisen vaiheet sekä perehdyttiin yleisimpiin varastopalvelutoimintoihin ja niiden kustannuslajeihin. Empiiriaosuudessa tutustuttiin Case-yrityksen varastointitoimintoihin, sen kustannuslaskennan nyky-tilaan ja kehityskohteisiin. Lopuksi laskentamallia testattiin yrityksen varastotoimin-toihin. Tutkimuksen tuloksena rakennetun laskentamallin todettiin antavan ymmärrettävää ja analyyttistä tietoa toimintojen ja laskentakohteiden kustannuksista. Laskentamallin tuloksien perusteella päästiin paremmin kiinni kustannusten aiheuttajiin ja tuloksia todettiin voitavan hyödyntää kustannustehokkuuden kehittämisessä. Suurena etuna voitiin täten pitää lisääntynyttä kustannustietoisuutta.

Epäpuhtausmetallien talteenotto sinkkiprosessissa

There are small amounts of valuable metals, such as indium, gallium and germanium, in zinc process solutions. Their solvent extraction was studied in this work in sulphate solutions containing zinc and other metals present in industrial solutions. It was discovered, that a commercial bis(2-ethylhexyl)phosphate (D2EHPA) extractant can be used to extract indium and gallium. Indium was extracted separately at a higher acid concentration than gallium. Zinc was co-extracted faster than gallium and almost as much as gallium at the same pH. However, the scrubbing of zinc was possible using a dilute sulphuric acid and a short contact time while gallium losses were small. Both indium and gallium were stripped with sulphuric acid. Germanium was extracted with 5,8-diethyl-7-hydroxydodecane-6-oxime with the commercial name of LIX 63. Unlike other metals in the solution the extraction of germanium increased with different extractants as the acidity increased. Germanium extraction isotherm was measured for a 125 g/L sulfuric acid solution. The loaded organic phase was washed with pure water. It removed the co-extracted acid and part of the germanium and extracted impurities such as iron and copper. Germanium was stripped using a NaOH solution. A process model utilizing own experimentally determined extraction, scrubbing and stripping isotherms was made with HSC Sim software developed by Outotec Oyj. The model based on McCabe–Thiele diagrams was used in sizing the necessary amount of stages and phase ratios in a recovery process. It was concluded, that indium, gallium and germanium can be recovered in the process from a feed where their concentrations are low (<300 ppm). In an example case the feed contained also more than 20 g/L zinc and 2–8 g/L iron, aluminium and copper. The recoveries of indium, gallium and germanium were more than 90 % when 1–3 stages were used in each extraction, scrubbing and stripping section. Since the number of stages is small mixer-settlers would be well suited for this purpose.

Use Of Systems Approach with Total Quality Management in Industrial Organizations

The objective of the work has been to study why systems thinking should be used in combination with TQM, what are the main benefits of the integration and how it could best be done. The work analyzes the development of systems thinking and TQM with time and the main differences between them. The work defines prerequisites for adopting a systems approach and the organizational factors which embody the development of an efficient learning organization. The work proposes a model based on combination of an interactive management model and redesign to be used for application of systems approach with TQM in practice. The results of the work indicate that there are clear differences between systems thinking and TQM which justify their combination. Systems approach provides an additional complementary perspective to quality management. TQM is focused on optimizing operations at the operational level while interactive management and redesign of organization are focused on optimization operations at the conceptual level providing a holistic system for value generation. The empirical study demonstrates the applicability of the proposed model in one case study company but its application is tenable and possible also beyond this particular company. System dynamic modeling and other systems based techniques like cognitive mapping are useful methods for increasing understanding and learning about the behavior of systems. The empirical study emphasizes the importance of using a proper early warning system.

Studies on the Multifaceted Interaction of Atoms and an Electromagnetic Field

In this Thesis the interaction of an electromagnetic field and matter is studied from various aspects in the general framework of cold atoms. Our subjects cover a wide spectrum of phenomena ranging from semiclassical few-level models to fully quantum mechanical interaction with structured reservoirs leading to non-Markovian open quantum system dynamics. Within closed quantum systems, we propose a selective method to manipulate the motional state of atoms in a time-dependent double-well potential and interpret the method in terms of adiabatic processes. Also, we derive a simple wave-packet model, based on distributions of generalized eigenstates, explaining the finite visibility of interference in overlapping continuous-wave atom lasers. In the context of open quantum systems, we develop an unraveling of non-Markovian dynamics in terms of piecewise deterministic quantum jump processes confined in the Hilbert space of the reduced system - the non-Markovian quantum jump method. As examples, we apply it for simple 2- and 3-level systems interacting with a structured reservoir. Also, in the context of ion-cavity QED we study the entanglement generation based on collective Dicke modes in experimentally realistic conditions including photonic losses and an atomic spontaneous decay.

Etelä-Karjalan sosiaali- ja terveyspiirin kuntakohtaisen kustannuslaskentamallin kehittäminen

Työn tavoitteena oli tutkia Etelä-Karjalan sosiaali- ja terveydenhuollon kuntayhtymän kuntalaskutusta ja rakentaa laskentamalli, jolla kuntakohtaiset kustannukset pystytään laskemaan ja jakamaan. Tutkimusote oli konstruktiivinen. Tiedot kerättiin kuntayhtymän toiminta- ja taloustietojärjestelmistä sekä haastattelemalla organisaation asiantuntijoita. Työn tulokseksi saatu laskentamalli koostuu suoritepohjaisesta, asukaslukupohjaisista ja tarvepainotetuista asukaslukupohjaisista kustannusajureista, joilla kustannukset jaetaan piirin jäsenkunnille. Tällä sekamallilla pystytään toteuttamaan kuntalaskutusta, sillä se täyttää kuntalaskutusmallille asetetut vaatimukset. Työn tulosten perusteella tulo-osuusmalli olisi paras tapa toteuttaa kuntalaskutusta. Yksinkertainen rahoitusmalli mahdollistaa toiminnan vapaamman kehittämisen kuin sekamalli ja on lisäksi selkeämpi ja läpinäkyvämpi. Sekamallissa tulisi painottaa tarvepohjaisia asukaslukuajureita. Tärkeimmät ja suurimpia kustannuksia aiheuttavat alueet kannattaisi tuotteistaa.

Microscopic simulation of pigment coating consolidation

The control of coating layer properties is becoming increasingly important as a result of an emerging demand for novel coated paper-based products and an increasing popularity of new coating application methods. The governing mechanisms of microstructure formation dynamics during consolidation and drying are nevertheless, still poorly understood. Some of the difficulties encountered by experimental methods can be overcome by the utilisation of numerical modelling and simulation-based studies of the consolidation process. The objective of this study was to improve the fundamental understanding of pigment coating consolidation and structure formation mechanisms taking place on the microscopic level. Furthermore, it is aimed to relate the impact of process and suspension properties to the microstructure of the coating layer. A mathematical model based on a modified Stokesian dynamics particle simulation technique was developed and applied in several studies of consolidation-related phenomena. The model includes particle-particle and particle-boundary hydrodynamics, colloidal interactions, Born repulsion, and a steric repulsion model. The Brownian motion and a free surface model were incorporated to enable the specific investigation of consolidation and drying. Filter cake stability was simulated in various particle systems, and subjected to a range of base substrate absorption rates and system temperatures. The stability of the filter cake was primarily affected by the absorption rate and size of particles. Temperature was also shown to have an influence. The consolidation of polydisperse systems, with varying wet coating thicknesses, was studied using imposed pilot trial and model-based drying conditions. The results show that drying methods have a clear influence on the microstructure development, on small particle distributions in the coating layer and also on the mobility of particles during consolidation. It is concluded that colloidal properties can significantly impact coating layer shrinkage as well as the internal solids concentration profile. Visualisations of particle system development in time and comparison of systems at different conditions are useful in illustrating coating layer structure formation mechanisms. The results aid in understanding the underlying mechanisms of pigment coating layer consolidation. Guidance is given regarding the relationship between coating process conditions and internal coating slurry properties and their effects on the microstructure of the coating.

Monitoring of centrifugal pump operation by a frequency converter

Centrifugal pumps are widely used in industrial and municipal applications, and they are an important end-use application of electric energy. However, in many cases centrifugal pumps operate with a significantly lower energy efficiency than they actually could, which typically has an increasing effect on the pump energy consumption and the resulting energy costs. Typical reasons for this are the incorrect dimensioning of the pumping system components and inefficiency of the applied pump control method. Besides the increase in energy costs, an inefficient operation may increase the risk of a pump failure and thereby the maintenance costs. In the worst case, a pump failure may lead to a process shutdown accruing additional costs. Nowadays, centrifugal pumps are often controlled by adjusting their rotational speed, which affects the resulting flow rate and output pressure of the pumped fluid. Typically, the speed control is realised with a frequency converter that allows the control of the rotational speed of an induction motor. Since a frequency converter can estimate the motor rotational speed and shaft torque without external measurement sensors on the motor shaft, it also allows the development and use of sensorless methods for the estimation of the pump operation. Still today, the monitoring of pump operation is based on additional measurements and visual check-ups, which may not be applicable to determine the energy efficiency of the pump operation. This doctoral thesis concentrates on the methods that allow the use of a frequency converter as a monitoring and analysis device for a centrifugal pump. Firstly, the determination of energy-efficiency- and reliability-based limits for the recommendable operating region of a variable-speed-driven centrifugal pump is discussed with a case study for the laboratory pumping system. Then, three model-based estimation methods for the pump operating location are studied, and their accuracy is determined by laboratory tests. In addition, a novel method to detect the occurrence of cavitation or flow recirculation in a centrifugal pump by a frequency converter is introduced. Its sensitivity compared with known cavitation detection methods is evaluated, and its applicability is verified by laboratory measurements for three different pumps and by using two different frequency converters. The main focus of this thesis is on the radial flow end-suction centrifugal pumps, but the studied methods can also be feasible with mixed and axial flow centrifugal pumps, if allowed by their characteristics.

Pilvisovelluskehitys Google App Engine -pilvisovellusalustalla

Tämä Diplomityö keskittyy tutkimaan pilvisovelluskehitystä Google App Engine – pilvisovellusalustalle perustuen kuusi –vaiheiseen vesiputousmalliin sekä tutkimaan Google App Engine -pilvisovellusalustan tarjoamia mahdollisuuksia ja rajoituksia sovelluskehityksen muodossa. Tutkimuksen perusteella kuusi –vaiheinen vesiputousmalli soveltuu pilvisovelluskehitykseen,mikäli vaatimusmäärittely on tarkka jo sovelluskehityksen alkuvaiheessa. Tutkimuksen tuloksena syntyi vaatimusmäärittely MikkoMail –pilvisovellukselle. Vaatimusmäärittelyn pohjalta luotiin MikkoMail –pilvisovellus Google App Engine –pilvisovellusalustalle. Google App Engine –pilvisovellusalusta tukee vain Python- ja Java –ohjelmointikieliä eikä sisällä lainkaan ulkoista tietokantapalveluiden tukea. Tästä syystä Google App Engine -pilvisovellusalusta soveltuu pieniin, keskisuuriin ja pilottiprojektinomaisiin sovelluskehitysprojekteihin.