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Visar resultat 1 - 5 av 14 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Synthesis and Characterization of Sec-Packings Based on Trimethylolpropane Trimethacrylate

    Författare :Andrea Schmid; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; bulk polymerization; N; hydrophilic gels; separation; methyl methacrylate; hydrophobic networks; acrylamide; porous networks; Suspension; N -methylene-bis-acrylamide; chemically crosslinked networks; dry gels; polysaccharide standards; distilled water; copolymerization; trimethylolpropane trimethacrylate;

    Sammanfattning : Suspension and bulk polymerization of trimethylolpropane trimethacrylate (TRIM) and copolymerization of TRIM with methyl methacrylate (MMA) resulted in porous, hydrophobic, and chemically crosslinked networks. Copolymerization of TRIM with acrylamide (AA) and with N,N'-methylene-bis-acrylamide (bis-AA) resulted in hydrophilic gels. LÄS MER

  3. 2. Hydrolytic degradation of dental composites and effects of silane-treatment and filler fraction on compressive strength and thermal expansion of composites

    Författare :Karl-Johan M. Söderholm; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Internal frictional theory; filler-matrix debonding; stress-corrosion; stressinfluenced diffusion; m icro-crack form ation; crazing; opacity; wear; osmotic pressure; hoop stresses;

    Sammanfattning : Some researchers have suggested that the weakest link of dental composites is the filler-matrix bond. However, due to incompleteness of information dealing with this bond and its stability in a humid environment, it was considered desirable to investigate the effect of water on this region, as well as the influence of filler bonding and filler fraction on compressive strength and thermal expansionExperimental composites containing different filler fractions of either silane-treated or untreated fillers were made. LÄS MER

  4. 3. Biophysical aspects of contact dermatitis and its prevention

    Författare :Natalia Kuzmina; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :;

    Sammanfattning : The skin, one of the largest organs of the body, is composed of three layers: the epidermis, dermis and subcutis. The outer most part of the epidermis i.e. LÄS MER

  5. 4. Skin sensitivity testing : a biophysical approach

    Författare :Miruna Nyren; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :;

    Sammanfattning : The skin is regarded as the largest organ of the body, although it is only a few millimetres thick; it is also the interface between the environment and the body's vital structures. Its large surface area is constantly exposed to physical factors, allergens, irritants and infectious agents. LÄS MER

  7. 5. Pheromones for modulating reproduction in cattle : biological potential of oestrus-related substances inintra- and inter-species chemical communication

    Författare :Kristina Nordéus; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : Declining dairy cow fertility, largely attributable to increasing milk yields, is of major concern to dairy farmers worldwide. New tools for reproductive management, to replace exogenous hormones, would be of great interest. Chemical communication in cattle has been suggested to cause modifications of the oestrous cycle. LÄS MER