Use of heterogeneous catalysts in methylic biodiesel production induced by microwave irradiation

The effect of different heterogeneous catalysts on the microwave-assisted transesterification of sunflower oil for the production of methylic biodiesel in a monomode microwave reactor is described. The experiments were carried out at 70 ºC with a 16:1 methanolsunflower oil molar ratio and different heterogeneous basic and acidic catalysts. The results showed that the microwave-heated reactions occur up to four times faster than those carried out with conventional heating. The reactions were performed with 24 catalysts; pure calcium oxide (CaO) and potassium carbonate, either pure or supported by alumina (K2CO3/Al2O3), were the most efficient catalysts.

Sisäisen toimittajan palvelutasosopimuksen kehittäminen ja toimitusvarmuuden parantaminen, CASE: oy Shell ab

Tämän tutkielman tarkoituksena on tehostaa toimitusketjua kehittämällä palvelutasosopimusta ja parantamalla toimitusvarmuutta toimittajan ja oy Shell ab:n välillä. Työssä perehdytään näiden kahden yrityksen väliseen sopimukseen ja toimitusvarmuutta kuvaavaan mittariin nimeltä Supplier OTIF. Nykytila arvioidaan molempien osalta ja mahdollisia parantavia toimenpiteitä tuodaan esille. Tämä tutkimus perustuu yrityksessä työskentelyn ohella haastatteluihin, kyselyihin sekä omiin havaintoihin eri osastoilla. Työn teoriaosuudessa tarkastellaan ostosopimuksen yleisintä kaupallista sisältöä. Lisäksi paneudutaan palveluyrityksen käytäntöihin, tulkitaan palveluyrityksen suorituskykyä ja sen mittaamista tunnuslukujen avulla. Tutkimus osoittaa, että niin palvelutasosopimus kuin toimitusvarmuuskin eivät ole riittävällä tasolla case-yrityksessä. Erityisesti osapuolien välistä yhteistyötä ja tiedonjakoa on parannettava tavoitteiden saavuttamiseksi. Työssä esiteltyjen kehitys- ja parannusehdotusten osittainen käyttöönotto aikaansai toimitusketjun tehokkaamman toiminnan. Case-yrityksen tuleekin harkita lisätoimenpiteiden käyttöönottoa. Toiminnan sekä yhteistyön parantaminen yhä edelleen jää case-yrityksen ja toimittajien yhteisesti tulevaisuudessa tehtävien ratkaisujen varaan.

Broiler breeder hen performance and egg hatchability during rainy season in Brazilian semi-arid region

Henhouse thermal comfort and bird age influence broiler breeder hen productivity; this way, the present research aimed to assess thermal comfort indexes and broiler breeder hen performance during winter in North East semi-arid region from Brazil, using a Cobb Avian 48 broiler strain at the age of 38 and 50 weeks. We measured the following bioclimatic indexes: air temperature and relative humidity, black globe temperature and humidity, CO2 concentration and sound pressure levels at henhouse facility. Data analysis design was complete randomized in a 3 x 3 factorial scheme with three treatments (months) and three replications (week number of collection by month). A number of 25 climatic data were observed. Bioclimatic indexes at the most warm hours throughout the day promoted bird discomfort yet sound pressure and carbon dioxide levels were under the Brazilian standards. Even in thermal comfort zone at some hours, the productivity indexes were in compliance with those recommended by the strain creation guidebook.

Fractionation of Hen Egg and Oat Lipids with supercritical Fluids Chemical and functional Properties of Fractions

Hen eggs and oats (Avena Sativa) are important materials for the food industry. Today, instead of merely satisfying the feeling of hunger, consumers are asking for healthier, biologically active and environmentally friendly products. The growing awareness of consumers’ increasing demands presents a great challenge to the food industry to develop more sustainable products and utilise modern and effective techniques. The modification of yolk fatty acid composition by means of feed supplements is well understood. Egg yolk phospholipids are polar lipids and are used in several applications including food, cosmetics, pharmaceuticals, and special nutrients. Egg yolk phospholipids are excellent emulsifiers, typically sold as mixtures of phospholipids, triacylglycerols, and cholesterol. However, highly purified and characterised phospholipids are needed in several sophisticated applications. Industrial fractionation of phospholipids is usually based on organic solvents. With these fractionation techniques, some harmful residues of organic solvents may cause problems in further processing. The objective of the present study was to investigate the methods to improve the functional properties of eggs, to develop techniques to isolate the fractions responsible for the specific functional properties of egg yolk lipids, and to apply the developed techniques to plant-based materials, too. Fractionation techniques based on supercritical fluids were utilised for the separation of the lipid fractions of eggs and oats. The chemical and functional characterisation of the fractions were performed, and the produced oat polar lipid fractions were tested as protective barrier in encapsulation processes. Modifying the fatty acid compositions of egg yolks with different types of oil supplements in feed had no affect on their functional or sensory properties. Based on the results of functional and sensory analysis, it is evident that eggs with modified fatty acid compositions are usable in several industrial applications. These applications include liquid egg yolk products used in mayonnaise and salad dressings. Egg yolk powders were utilised in different kinds of fractionation processes. The precipitation method developed in this study resembles the supercritical anti-solvent method, which is typically used in the pharmaceutical industry. With pilot scale supercritical fluid processes, non-polar lipids and polar lipids were successfully separated from commercially produced egg yolk powder and oat flakes. The egg and oat-based polar lipid fractions showed high purities, and the corresponding delipidated fractions produced using supercritical techniques offer interesting starting materials for the further production of bioactive compounds. The oat polar lipid fraction contained especially digalactosyadiacylglycerol, which was shown to have valuable functional properties in the encapsulation of probiotics.

Development of racemization catalysts for dynamic kinetic resolution

Preparation of optically active compounds is of high importance in modern medicinal chemistry. Despite recent advances in the field of asymmetric synthesis, resolution of racemates still remains the most utilized way for preparation of single enantiomers in industrial scale due to its cost-efficiency and simplicity. Enzymatic kinetic resolution (KR) of racemates is a classical method for separation of enantiomers. One of its drawbacks is the limitation of target enantiomer yield to 50%. Dynamic Kinetic Resolution (DKR) allows to reach yields up to 100% by in situ racemization of the less reactive enantiomer. In the first part of this thesis, a number of half-sandwich ruthenium complexes were prepared and evaluated as catalysts for racemization of optically active secondary alcohols. A leading catalyst, Bn5CpRu(CO)2Cl, was identified. The catalyst discovered was extensively characterized by its application for DKR of a broad range of secondary alcohols in a wide range of reaction loadings (1 mmol – 1 mol). Cost-efficient chromatography-free procedure for preparation of this catalyst was developed. Further, detailed kinetic and mechanistic studies of the racemization reactions were performed. Comparison of racemization rates in the presence of Bn5CpRu(CO)2Cl and Ph5CpRu(CO)2Cl catalysts reveals that the performance of the catalytic system can be adjusted by matching of the electronic properties of the catalysts and the substrates. Moreover, dependence of the rate-limiting step from the electronic properties of the reagents was observed. Important conclusions about reaction mechanism were made. Finally, an alternative approach to DKR of amines based on space separated vessels was addressed. This procedure allows the combination of thermolabile enzyme with racemization catalysts active only at high temperatures.

Tukkukauppiaille : Shell hintaluettelo C

kuv., 21 x 27 cm

Shell huolto

kuv., 15 x 22 cm

Kuluttajille : Shell hintaluettelo C

kuv., 21 x 27 cm

Shell service

kuv., 15 x 22 cm

Kuluttajille : Shell hintaluettelo C

kuv., 22 x 27 cm

Shell prislista

kuv., 22 x 28 cm

Shell huolto

kuv., 15 x 22 cm

Kuluttajille : Shell hintaluettelo C

kuv., 22 x 27 cm

Shell service

kuv., 15 x 22 cm