Crack AutoCAD Mechanical 2014 Key: A Complete Guide for Beginners
1. BASIC CONCEPTS: restoration, conservation, strengthening2. THE NORMATIVE SYSTEM: Heritage Conservation Act, Guidelines for heritage preservation from seismic risks, Technical laws for existing buildings, historical manuals.3. THE KNOWLEDGE PATH: Historical measuring units, proportions and original geometry, historical inspections (archives documents, building manuals, historical "reading" of the building); the survey of geometry, architecture, structure, materials, disorders, decay phenomena, crack pattern; experimental tests, structural monitoring.4. ART AND SCIENCE OF BUILDING: some concepts of building science and technique, equilibrium, graphic statics, stress-strain relations, strength, no-tension materials; hyper-static structures; ultimate state assessment on empirical basis.5. TIMBER STRUCTURAL ELEMENTS: Materials characteristics, decay phenomena, structural problems, timber floors and roofs, post trusses.6. MASONRY STRUCTURAL ELEMENTS: Materials characteristics, mechanical behaviour, pillars and columns, walls, seismic behavior of traditional masonry buildings.7. ARCHES, VAULTS AND DOMES: building typologies, static behaviour, disorders and crack pattern, collapse mechanisms, graphical methods for the limit state analysis, finite element analysis, strengthening techniques.8. STRENGTHENING METHODS: traditional and innovative techniques and materials for the structural and seismic strengthening of historical buildings; the difficult equilibrium between safety and conservation; theoretical, aesthetical and functional issues in the structural restoration.9. BUILDING'S HVAC SYSTEM: HVAC adaptation, with specific reference to the compatibility problems 10. EXAMPLES OF RESTORATION AND STRENGTHENING: design and project references, in the frame of the complex cultural debate ongoing in this field.
crack AutoCAD Mechanical 2014 key
Bio-functionalizing surface treatments are often applied for improving the bioactivity of biomaterials that are based on otherwise bioinert titanium alloys. When applied on highly porous titanium alloy structures intended for orthopedic bone regeneration purposes, such surface treatments could significantly change the static and fatigue properties of these structures and, thus, affect the application of the biomaterial as bone substitute. Therefore, the interplay between biofunctionalizing surface treatments and mechanical behavior needs to be controlled. In this paper, we studied the effects of two bio-functionalizing surface treatments, namely alkali-acid heat treatment (AlAcH) and acid-alkali (AcAl), on the static and fatigue properties of three different highly porous titanium alloy implants manufactured using selective laser melting. It was found that AlAcH treatment results in minimal mass loss. The static and fatigue properties of AlAcH specimens were therefore not much different from as-manufactured (AsM) specimens. In contrast, AcAl resulted in substantial mass loss and also in significantly less static and fatigue properties particularly for porous structures with the highest porosity. The ratio of the static mechanical properties of AcAl specimens to that of AsM specimen was in the range of 1.5-6. The fatigue lives of AcAl specimens were much more severely affected by the applied surface treatments with fatigue lives up to 23 times smaller than that of AsM specimens particularly for the porous structures with the highest porosity. In conclusion, the fatigue properties of surface treated porous titanium are dependent not only on the type of applied surface treatment but also on the porosity of the biomaterial. Copyright 2014 Elsevier Ltd. All rights reserved.
The aim of the present study was to investigate the mechanical and thermal properties of mixed chitosan-acemannan (CS-AC) mixed gels and the antibacterial activity of dilute mixed solutions of both polysaccharides. Physical hydrogels of chitosan comprising varying amounts of non-gelling acemannan were prepared by controlled neutralization of chitosan using ammonia. As the overall acemannan concentration in the mixed hydrogel increased while fixing that of CS, the mechanical strength decreased. These results indicate that AC perturbs the formation of elastic junctions and overall connectivity as it occurs in the isolated CS network. Heterotypic associations between CS and AC leading to the formation of more compact microdomains may be at play in reducing the density of the gel network consolidated by CS, possibly due to shorter gel junctions. Micro-DSC studies at pH 12.0 seem consistent with the suggestion that molecular heterotypic associations between CS and AC may be at play in determining the overall physical properties of the mixed gel systems. In dilute solution, CS showed antimicrobial activity against Staphylococcus aureus but not against Escherichia coli; AC did not exert antimicrobial activity against any of the two bacterial species. In blended solutions of both polysaccharides, as the amount of AC increased, the antimicrobial activity of the system against S. aureus ceased. In conclusion, this study demonstrates that it is feasible to incorporate acemannan in chitosan-acemannan gels and that although the mechanical strength decreases due to the presence of AC, the gel network persists even at high amount of AC. This study anticipates that the CS-AC mixed gels may offer promise for the future development of biomaterials such as scaffolds to be used in wound therapy. Copyright 2014 Elsevier Ltd. All rights reserved.