Seiberling hinnasto n:o 25

kuv., 11 x 14 cm

Falcon 25 venemoottorit

kuv., 16 x 24 cm

Proceedings of the PDM2013 conference, LUT 24.-25.4.2013

The 1st PDM Forum for Finland-Russia Collaboration was held at Lappeenranta University of Technology, Finland, during 25.-26.4.2013. The forum brought together leading academics, practitioners, advisors, engineers, industrial experts, and software vendors from Finland and Russia. The forum can be seen as a new integrating element between Russian and Finnish industries and universities. Over border connections between Russia and Finland may also bring new contacts and ideas to develop and expand businesses. Meeting different universities professors, PhD students, and companies’ agents facilitates the sharing and discussion of current PDM (Product Data Management) issues.

Desenvolvimento corporal e testicular em machos de codornas de corte e de postura de 25 a 360 dias

Codornas do tipo carne e tipo ovos foram analisadas para determinar o desenvolvimento reprodutivo, a puberdade e o início da senilidade. Para tal, 288 codornas (144 codornas de corte e 144 de postura) foram acompanhadas desde a eclosão até os 360 dias de idade. As aves foram distribuídas por idade em 18 grupos, sendo 8 codornas/grupo/tipo de codorna. Após 35 dias as codornas foram mantidas em condições de fotoperíodo de dias longos (17luz: 7escuro). O peso vivo e os valores morfométricos e histológicos testiculares foram determinados em cada período. Os dados obtidos foram analisados para determinar a curva de crescimento e o comportamento dos parâmetros analisados. O modelo que mais se adequou aos dados foi o modelo não linear de Gompertz (Y=A exp [-B e (-kt)]). O peso vivo e as características testiculares macro e microscópicas apresentaram comportamento alométrico entre si, sendo que, aproximadamente aos 60 dias os machos apresentaram-se sexualmente desenvolvidos, e estabilizaram o peso corporal por volta dos 100 dias. O testículo direito é mais cranial que o esquerdo e diferem em relação a comprimento e largura, porém não foi observada diferenças (P>0,05) para peso testicular. As codornas de corte apresentaram peso corporal e peso testicular maiores que as codornas de postura, porém as codornas de postura apresentaram peso relativo testicular maior. Durante todo o período analisado os machos puderam ser considerados sexualmente aptos. Os reprodutores apresentaram características sexuais ativas até os 360 dias de idade, representadas pelo tamanho testicular e pela atividade celular nos túbulos seminíferos.

Hydrodynamics Characteristics and Gas-Liquid Mass Transfer in a Three Phase Fluidized Bed Reactor

This paper presents the experimental characterization of hydrodynamics and gas-liquid mass transfer in a three-phase fluidized bed containing polystyrene and nylon particles. The influence of gas and liquid velocities on phase holdups and volumetric gas-liquid mass transfer coefficient was investigated for flow conditions similar to those applied in biotechnological process. The phase holdups were obtained by the pressure profile technique. The volumetric gas-liquid mass transfer coefficient was obtained adjusting the experimental concentration profiles of dissolved oxygen in the liquid phase with the predictions of the axial dispersion model. According to experimental results the liquid holdup increases with the gas velocity, whereas the solid holdup decreases. The gas holdup increases significantly with the increase in gas velocity, and it shows for the three-phase fluidized bed comparable values or larger than those of bubble column. The volumetric gas-liquid mass transfer coefficient increases significantly with an increase in the air velocity for both bubble column and fluidized beds. In addition, in the operational condition of high liquid velocity, the presence of low-density particles in the bed increased the gas-liquid mass transfer, and thus the volumetric mass transfer coefficient values obtained in the fluidized bed were comparable or larger than those of bubble column.

Development of a process for the direct synthesis of hydrogen peroxide in a novel microstructured reactor

Microreactors have proven to be versatile tools for process intensification. Over recent decades, they have increasingly been used for product and process development in chemical industries. Enhanced heat and mass transfer in the reactors due to the extremely high surfacearea- to-volume ratio and interfacial area allow chemical processes to be operated at extreme conditions. Safety is improved by the small holdup volume of the reactors and effective control of pressure and temperature. Hydrogen peroxide is a powerful green oxidant that is used in a wide range of industries. Reduction and auto-oxidation of anthraquinones is currently the main process for hydrogen peroxide production. Direct synthesis is a green alternative and has potential for on-site production. However, there are two limitations: safety concerns because of the explosive gas mixture produced and low selectivity of the process. The aim of this thesis was to develop a process for direct synthesis of hydrogen peroxide utilizing microreactor technology. Experimental and numerical approaches were applied for development of the microreactor. Development of a novel microreactor was commenced by studying the hydrodynamics and mass transfer in prototype microreactor plates. The prototypes were designed and fabricated with the assistance of CFD modeling to optimize the shape and size of the microstructure. Empirical correlations for the mass transfer coefficient were derived. The pressure drop in micro T-mixers was investigated experimentally and numerically. Correlations describing the friction factor for different flow regimes were developed and predicted values were in good agreement with experimental results. Experimental studies were conducted to develop a highly active and selective catalyst with a proper form for the microreactor. Pd catalysts supported on activated carbon cloths were prepared by different treatments during the catalyst preparation. A variety of characterization methods were used for catalyst investigation. The surface chemistry of the support and the oxidation state of the metallic phase in the catalyst play important roles in catalyst activity and selectivity for the direct synthesis. The direct synthesis of hydrogen peroxide was investigated in a bench-scale continuous process using the novel microreactor developed. The microreactor was fabricated based on the hydrodynamic and mass transfer studies and provided a high interfacial area and high mass transfer coefficient. The catalysts were prepared under optimum treatment conditions. The direct synthesis was conducted at various conditions. The thesis represents a step towards a commercially viable direct synthesis. The focus is on the two main challenges: mitigating the safety problem by utilization of microprocess technology and improving the selectivity by catalyst development.

Novel technology for preparation of optically active chemicals

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.

Optiohinnoittelumallien empiirinen vertailu OMX 25 Helsinki -warranttimarkkinoilla

Tämän tutkimuksen tarkoituksena on selvittää pystytäänkö OMX 25 Helsinki kohde-etuusindeksin warranttien hintoja ennustamaan käyttämällä erilaisia optiohinnoittelumalleja. Tutkielman aineisto koostuu OMXH25-indeksiä seuraavien warranttien hinta-aikasarjatiedoista vuosilta 2009-2011. Tutkimuksessa käytettiin kolmea eri hinnoittelumallia warranttien hinnoitteluvirheiden tutkimiseen. Perinteistä Black-Scholes-hinnoittelumallia käytettiin siten, että warranttiaineistosta joh-dettu implisiittinen volatiliteetti regressoitiin maturiteetin ja toteutushinnan mu-kaan, jonka jälkeen regression perusteella valittiin kulloiseenkin tilanteeseen sopiva volatiliteettiestimaatti. Black-Scholes-mallin lisäksi tutkimuksessa käy-tettiin kahta GARCH-pohjaista optiohinnoittelumallia. Mallien estimoimia hin-toja verrattiin markkinoiden warranttihintoihin. Tulosten perusteella voitiin todeta, että mallit onnistuvat hinnoittelemaan war-rantteja paremmin lyhyen ajan päähän mallien kalibroinnista. Tulokset vaihte-livat suuresti eri vuosien välillä eikä minkään käytetyn mallin nähty suoriutu-van systemaattisesti muita malleja paremmin.

Molecular characteristics of Machado-Joseph disease mutation in 25 newly described Brazilian families

Machado-Joseph disease (MJD) is a form of autosomal dominant spinocerebellar ataxia first described in North-American patients originating from the Portuguese islands of the Azores. Clinically this disorder is characterized by late onset progressive ataxia with associated features, such as: ophthalmoplegia, pyramidal and extrapyramidal signs and distal muscular atrophies. The causative mutation is an expansion of a CAG repeat in the coding region of the MJD1 gene. We have identified 25 unrelated families segregating the MJD mutation during a large collaborative study of spinocerebellar ataxias in Brazil. In the present study a total of 62 family members were genotyped for the CAG repeat in the MJD1 gene, as well as 63 non-MJD individuals (126 normal chromosomes), used as normal controls. We observed a wide gap between the size range of the normal and expanded CAG repeats: the normal allele had from 12 to 33 CAGs (mean = 23 CAGs), whereas the expanded alleles ranged from 66 to 78 CAGs (mean = 71.5 CAGs). There were no differences in CAG tract length according to gender of affected individuals or transmitting parent. We observed a significant negative correlation between age at onset of the disease and length of the CAG tract in the expended allele (r = -0.6, P = 0.00006); however, the size of the expanded CAG repeat could explain only about 40% of the variability in age at onset (r2 = 0.4). There was instability of the expanded CAG tract during transmission from parent to offspring, both expansions and contractions were observed; however, there was an overall tendency for expansion, with a mean increase of +2.4 CAGs. The tendency for expansion appeared to the greater in paternal (mean increase of +3.5 CAGs) than in maternal transmissions (mean increase of +1.3 CAGs). Anticipation was observed in all transmissions in which ages at onset for parent and offspring were known; however, anticipation was not always associated with an increase in the expanded CAG repeat length. Our results indicate that the molecular diagnosis of MJD can be confirmed or excluded in all suspected individuals, since alleles of intermediary size were not observed.

Über die Vertheilung der Bewohner Russlands nach Ständen, in den verschiedenen Provinzen: Eingereicht den 13 (25.) Januar 1843; neu bearbeitet im November 1846

Eripainos.

Catalytic direct synthesis of hydrogen peroxide in a novel microstructured reactor

The direct synthesis from hydrogen and oxygen is a green alternative for production of hydrogen peroxide. However, this process suffers from two challenges. Firstly, mixtures of hydrogen and oxygen are explosive over a wide range of concentrations (4-94% H2 in O2). Secondly, the catalytic reaction of hydrogen and oxygen involves several reaction pathways, many of them resulting in water production and therfore decreasing selectivity. The present work deals with these two challenges. The safety problem was dealed by employing a novel microstructured reactor. Selectivity of the reaction was highly improved by development a set of new catalysts. The final goal was to develop an effective and safe continuous process for direct synthesis of hydrogen peroxide from H2 and O2. Activated carbon cloth and Sibunit were examined as the catalysts’ supports. Palladium and gold monometallic and palladium-gold bimetallic catalysts were thoroughly investigated by numerous kinetic experiments performed in a tailored batch reactor and several catalyst charachterization methods. A complete set of data for direct synthesis of H2O2 and its catalytic decomposition and hydrogenation was obtained. These data were used to assess factors influencing selectivity and activity of the catalysts in direct synthesis of H2O2 as well as its decomposition and hydrogenation. A novel microstructured reactor was developed based on hydrodynamics and mass transfer studies in prototype microstractural plates. The shape and the size of the structural elements in the microreactor plate were optimized in a way to get high gas-liquid interfacial area and gas-liquid mass transfer. Finally, empirical correlations for the volumetric mass transfer coefficient were derived. A bench-scale continuous process was developed by using the novel microstructral plate reactor. A series of kinetic experiments were performed to investigate the effects of the gas and the liquid feed rates and their ratio, the amount of the catalyst, the gas feed composition and pressure on the final rate of H2O2 production and selectivity.

Long-term outcome of 25 children and adolescents with severe aplastic anemia treated with antithymocyte globulin

Severe aplastic anemia (SAA) is probably an immune-mediated disorder, and immunosuppressive therapy is recommended for patients with no available donor for bone marrow transplant. Between October 1984 and November 1987, 25 consecutive children and adolescents with SAA with no HLA-compatible marrow donor received equine antithymocyte globulin (ATG) (15 mg kg-1 day-1) for 10 days. The patients were evaluated 6 weeks, 6 months, and 12 months after starting ATG treatment. Thereafter, patients were evaluated yearly until July 1998. Median age was 10 years (range, 1.5-20 years), granulocyte counts on referral ranged from 0.032 to 1.4 x 10(9)/l (median 0.256 x 10(9)/l), and 12 patients had granulocyte counts <0.2 x 10(9)/l. At a median follow-up of 9.6 years (range, 8.6-11.8 years), 10 patients (40%) remained alive with good marrow function. No morphologic evidence of hematological clonal disorders has been observed, although two patients probably have acquired clonal chromosomal abnormalities (trisomy 8 and del(6)q21, respectively). Responses to ATG were observed between 6 weeks and 6 months from the start of treatment in 60% of evaluable patients. The response rate was not different in patients whose granulocyte count at diagnosis was <0.2 x 10(9)/l, or in those who were <10 years of age. This study supports the view that, when compared with supportive measures, ATG is an effective treatment for children or adolescents with SAA. Although these results are inferior to those reported for marrow transplantation or more intensive immunosuppressive regimens, these patients who responded to ATG are long-term survivors with stable peripheral blood counts and a low rate of relapse.