Sökning: "Grinding mechanisms"

Visar resultat 1 - 5 av 18 avhandlingar innehållade orden Grinding mechanisms.

1. 1. Designing grinding tools to control and understand fibre release in groundwood pulping

   Författare :Magnus Heldin; Urban Wiklund; Birgitta Engberg; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Groundwood pulping; Grinding mechanisms; Diamond grinding tool; Energy efficiency; Teknisk fysik med inriktning mot tribomaterial; Engineering Science with specialization in Tribo Materials;

   Sammanfattning : Mechanical pulping is a very energy demanding process in which only a fraction of the energy is used for the actual separation of wood fibres. The rest of the energy is lost, partly in damaging already separated fibres and partly as heat during viscoelastic deformation of the wood. LÄS MER

3. 2. Application of Chemical Additives in Minerals Beneficiation – Implications on Grinding and Flotation Performance

   Författare :Vitalis Chipakwe; Saeed Chehreh Chelgani; Jan Rosenkranz; Tommy Karlkvist; Irina Chernyshova; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Energy; Grinding aid; Flowability; Dry grinding; FT4 Powder Rheometer; Surface properties; Rheology; Flotation; Polymers; Surface chemistry; Green Chemistry; Mineral Processing; Mineral Processing; Mineralteknik;

   Sammanfattning : The application of chemical additives, known as grinding aids (GAs), dates to 1930 in the cement industry. Unlike the cement industry, where the use of GAs is in the final processing step, it could be one of the first processing steps in ore beneficiation. LÄS MER

4. 3. High temperature galling : influencing parameters and mechanisms

   Författare :Leonardo Pelcastre; Jens Bergström; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Maskinelement; Machine Elements; Centrumbildning - Centrum för högpresterande stål CHS ; Centre - Centre for High Performance Steel CHS ;

   Sammanfattning : Damage of forming tools at elevated temperatures is a major problem in metal forming processes such as hot stamping. Of special importance is the occurrence of adhesion and gross material transfer from the work-piece to the tool surface, a phenomenon known as galling. LÄS MER

5. 4. Sulphide mineral flotation : a new insight into oxidation mechanisms

   Författare :Alireza Javadi; Jan D. Miller; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mineralteknik; Mineral Processing;

   Sammanfattning : Formation of hydrogen peroxide (H2O2), an oxidizing agent stronger than oxygen, by sulphide minerals during grinding was investigated. It was found that pyrite (FeS2), chalcopyrite (CuFeS2), sphalerite ((Zn,Fe)S), and galena (PbS), which are the most abundant sulphide minerals on Earth, generated H2O2 in pulp liquid during wet grinding in the presence or devoid of dissolved oxygen in water and also when the freshly ground solids are placed in water immediately after dry grinding. LÄS MER

7. 5. Experimental tooth clenching : a model for studying mechanisms of muscle pain

   Författare :Andreas Dawson; Malmö högskola; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; tooth clenching; muscle pain; bruxism; Delphi technique; pain measurement; masticatory muscles; experimental pain; proprioceptive allodynia; temporomandibular disorders; serotonin; glutamate; masseter muscle; microdialysis;

   Sammanfattning : “I felt like I’d done three rounds with Mike Tyson…all becauseI was grinding my teeth in my sleep”, så beskrev en patient somintervjuades av Daily Mail i en artikel där det ökade problemet medöverbelastning i käkarna beskrevs, vilket kan leda till tandslitage,muskelsmärta, och frakturer på tandmaterial. Det personliga lidandet,och de ekonomiska kostnaderna för både individ och samhälle ärstort. LÄS MER