Effects of repeated slash removal in thinned stands on soil chemistry and understorey vegetation

Abstract

Influence of topography and surface chemistry on the wetting properties of TiO2-based ceramic coatings

Vätning av fasta ytor är ett viktigt fenomen i såväl naturen som i en lång rad av industriella tillämpningar. Det är allmänt känt att vätningen av en fast yta styrs av ytans kemi samt struktur. Målsättningen med avhandlingen var att studera hur kemisk heterogenitet och ytråhet på nanometernivå påverkar vätningsegenskaperna hos en fast yta. Ytorna som studerades var titandioxid-baserade kerama ytor som framställdes med hjälp av en sol-gel process. Vätningstudierna utfördes genom kontaktvinkelmätningar, vilket innebär att man mäter vinkeln som vätska/luft-gränsskiktet hos en vätskedroppe bildar mot en fast yta. Ytråheten hos materialen studerades främst genom atomkraftsmikroskopi (AFM). I AFM detekteras ytans struktur av en mycket skarp nål som skannar ytan. Resultaten i avhandlingen kunde framgångsrikt modelleras med existerande teorier för vätning av heterogena ytor.

Episodes in carbohydrate chemistry : from β-linked mannosides to glycoconjugates

Carbohydrates are one of the most abundant classes of biomolecules on earth. In the initial stages of research on carbohydrates much effort was focused on investigation and determination of the structural aspects and complex nature of individual monosaccharides. Later on, development of protective group strategies and methods for oligosaccharide synthesis became the main topics of research. Today, the methodologies developed early on are being utilized in the production of carbohydrates for biological screening events. This multidisciplinary approach has generated the new discipline of glycobiology which focuses on research related to the appearance and biological significance of carbohydrates. In more detail, studies in glycobiology have revealed the essential roles of carbohydrates in cell-cell interactions, biological recognition events, protein folding, cell growth and tumor cell metastasis. As a result of these studies, carbohydrate derived diagnostic and therapeutic agents are likely to be of growing interest in the future. In this doctoral thesis, a journey through the fundamentals of carbohydrate synthesis is presented. The research conducted on this journey was neither limited to the study of any particular phenomena nor to the addressing of a single synthetic challenge. Instead, the focus was deliberately shifted from time to time in order to broaden the scope of the thesis, to continue the learning process and to explore new areas of carbohydrate research. Throughout the work, several previously reported synthetic protocols, especially procedures related to glycosylation reactions and protective group manipulations, were evaluated, modified and utilized or rejected. The synthetic molecules targeted within this thesis were either required for biological evaluations or utilized to study phenomena occuring in larger molecules. In addition, much effort was invested in the complete structural characterization of the synthesized compounds by a combination of NMR spectroscopic techniques and spectral simulations with the PERCH-software. This thesis provides the basics of working with carbohydrate chemistry. In more detail, synthetic strategies and experimental procedures for many different reactions and guidelines for the NMR-spectroscopic characterization of oligosaccharides and glycoconjugates are provided. Therefore, the thesis should prove valuable to researchers starting their own journeys in the ever expanding field of carbohydrate chemistry.

Surface chemistry of fibres and vessel elements in chemical and recycled pulps

Den viktigaste råvaran i papperstillverkning är pappersmassa. Massan innehåller (ved)fibrer men också finmaterial och andra typers (ved)celler, så som kärlceller. Hur dessa komponenter beter sig under arkformationen i pappersmaskinen eller hur de bidrar till egenskaperna hos det färdiga pappret avgörs till stor del av massakomponenternas ytkemiska sammansättning, fysiska struktur och mängden joniserbara grupper på ytan. I denna avhandling studerades ytegenskaperna hos fraktionerade kemiska massor och returfibermassor med avancerade analystekniker. Rester av avfärgningskemikalier identifierades på både returfibrer och på kärlceller. Dessa kan påverka arkformationen och arkstyrkan på returfiberpapper. Kärlcellernas cellväggsstruktur visade sig skilja sig från fibrernas. Resultaten kan främja utvecklingen av returfiberprosessen och användningen av kärlcellsrika lövvedsmassor.

Aggression and its Management in Adolescent Forensic Psychiatric Care

The overall goal of this study was to explore and identify good aggression management methods and on that basis to produce recommendations for aggression management in the adolescent forensic setting. The study was conducted in three phases. In Phase I, staff’s (n = 58) perception of adolescent aggressive behaviour and methods to manage it was examined. In Phase II, staff’s (n = 30) perception of treatment settings and treatment interventions available were studied. In Phase III, the effectiveness of an aggression management programme was evaluated. The data were collected during the period 2004-2007. Participants perceived adolescent aggressive behaviour in a similar way and described aggressive behaviour as being a comprehensible phenomenon. Management methods used to control aggressive situations were alike, although the practical solutions varied between the study units, especially regarding coercive methods. Staff members proposed more time and better opportunities to discuss and evaluate the aggression situation in order to improve the methods used. The treatment settings were similar in studied forensic units and interventions were primarily focused on psychological aspects, including management of aggressive behavior. A comprehensive aggression management programme proved to be effective in decreasing incidents of violence. The use of coercive methods in aggression situations decreased and injuries to the staff became less frequent. If staff members intend to apply high quality management methods in aggression situations they have to share a consistent understanding of aggressive behaviour and need to be aware of the various methods available. In addition, they should learn more about assessment methods in order to improve aggression management. International comparison of aggression, methods for managing it and service provision creates a starting point for developing equal care provision and realization within and between European countries.

Computational chemistry studies of wood-derived lignans

This thesis is based on computational chemistry studies on lignans, focusing on the naturally occurring lignan hydroxymatairesinol (HMR) (Papers I II) and on TADDOL-like conidendrin-based chiral 1,4-diol ligands (LIGNOLs) (Papers III V). A complete quantum chemical conformational analysis on HMR was previously conducted by Dr. Antti Taskinen. In the works reported in this thesis, HMR was further studied by classical molecular dynamics (MD) simulations in aqueous solution including torsional angle analysis, quantum chemical solvation e ect study by the COnductorlike Screening MOdel (COSMO), and hydrogen bond analysis (Paper I), as well as from a catalytic point of view including protonation and deprotonation studies at di erent levels of theory (Paper II). The computational LIGNOL studies in this thesis constitute a multi-level deterministic structural optimization of the following molecules: 1,1-diphenyl (2Ph), two diastereomers of 1,1,4-triphenyl (3PhR, 3PhS), 1,1,4,4-tetraphenyl (4Ph) and 1,1,4,4-tetramethyl (4Met) 1,4-diol (Paper IV) and a conformational solvation study applying MD and COSMO (Paper V). Furthermore, a computational study on hemiketals in connection with problems in the experimental work by Docent Patrik Eklund's group synthesizing the LIGNOLs based on natural products starting from HMR, is shortly described (Paper III).

On Bayesian predictive modeling : with applications on the analysis of chromatography data in forensic investigations

Med prediktion avses att man skattar det framtida värdet på en observerbar storhet. Kännetecknande för det bayesianska paradigmet är att osäkerhet gällande okända storheter uttrycks i form av sannolikheter. En bayesiansk prediktiv modell är således en sannolikhetsfördelning över de möjliga värden som en observerbar, men ännu inte observerad storhet kan anta. I de artiklar som ingår i avhandlingen utvecklas metoder, vilka bl.a. tillämpas i analys av kromatografiska data i brottsutredningar. Med undantag för den första artikeln, bygger samtliga metoder på bayesiansk prediktiv modellering. I artiklarna betraktas i huvudsak tre olika typer av problem relaterade till kromatografiska data: kvantifiering, parvis matchning och klustring. I den första artikeln utvecklas en icke-parametrisk modell för mätfel av kromatografiska analyser av alkoholhalt i blodet. I den andra artikeln utvecklas en prediktiv inferensmetod för jämförelse av två stickprov. Metoden tillämpas i den tredje artik eln för jämförelse av oljeprover i syfte att kunna identifiera den förorenande källan i samband med oljeutsläpp. I den fjärde artikeln härleds en prediktiv modell för klustring av data av blandad diskret och kontinuerlig typ, vilken bl.a. tillämpas i klassificering av amfetaminprover med avseende på produktionsomgångar.

Iron(III) as Lewis acid catalyst in organosilicon and carbonyl chemistry

Iron is one of the most common elements in the earth’s crust and thus its availability and economic viability far exceed that of metals commonly used in catalysis. Also the toxicity of iron is miniscule, compared to the likes of platinum and nickel, making it very desirable as a catalyst. Despite this, prior to the 21st century, the applicability of iron in catalysis was not thoroughly investigated, as it was considered to be inefficient and unselective in desired transformations. In this doctoral thesis, the application of iron catalysis in combination with organosilicon reagents for transformations of carbonyl compounds has been investigated together with insights into iron catalyzed chlorination of silanes and silanols. In the first part of the thesis, the synthetic application of iron(III)-catalyzed chlorination of silanes (Si-H) and the monochlorination of silanes (SiH2) using acetyl chloride as the chlorine source is described. The reactions proceed under ambient conditions, although some compounds need to be protected from excess moisture. In addition, the mechanism and kinetics of the chlorination reaction are briefly adressed. In the second part of this thesis a versatile methodology for transformation of carbonyl compounds into three different compound classes by changing the conditions and amounts of reagents is discussed. One pot reductive benzylation, reductive halogenation and reductive etherification of ketones and aldehydes using silanes as the reducing agent, halide source or cocatalyst, were investigated. Also the reaction kinetics and mechanism of the reductive halogenation of acetophenone are briefly discussed.

Water chemistry management for future large experimental facilities

The thesis focuses on the water chemistry of the experimental test facilities and their reference VVER reactors. The main objective of the thesis is to provide recommendations for water chemistry management for laboratory facilities (VEERA, PACTEL) simulating the VVERs and for the large future facilities of the Lappeenranta University of Technology. In the beginning, the concept of nuclear power generation and the applicability of the nuclear power usage is discussed. Next, different water chemistry and water purification systems in primary and secondary circuits currently used at the power plant have been outlined. Also the construction geometry and design of test facilities PACTEL and VEERA, as well as the operation principles of their main equipment has been described. Finally, the appropriate water chemistry and water treatment system have been proposed for the existing and future experimental facilities of LUT.

Internet-markkinoinnin kehittäminen: Case Outotec HSC Chemistry

Kandidaatintyö käsittelee ohjelmistojen markkinointia internetissä ja markkinoinnin mittaamista. Työssä esitellään internetin eri markkinointikanavat käsitellen niiden toteutustapoja, vahvuuksia ja heikkouksia sekä kustannuksia. Internet-markkinoinnin mittaamisesta käsitellään erilaisia tunnuslukuja sekä mittaamisen käyttökohteita. Työ on pääasiassa kirjallisuuskatsaus, mutta samalla myös case: työssä käsitellään Outotecin toimeksiannosta sen kehittämän HSC Chemistry -ohjelmiston markkinointia internetissä. Työn tuloksissa suositellaan HSC Chemistrylle sopivia markkinointikanavia ja niiden kustannuksia. Lisäksi arvioidaan käsiteltyjen mittaamistapojen soveltuvuutta ohjelmiston tapauksessa.