The Estimation of Mechanical Properties of Polymers from Molecular Structure ppt

... the theoreticians the approximate form to which their theories may be reduced. Linking the mechanical properties to the molec- ular properties of a material is the equation of state. Thermodynamic ... dependence of a polymer is strongly related to the entanglement molecular weight. Above 2Me, the viscosity of the melt in- creases as the 3.4 power of...

Ngày tải lên: 01/04/2014, 00:20

... gaps of Ge- core/Si-shell and Si-core/Ge-shell nanowires at the level of density functional theory, where the composition is defined as the ratio of the number of atoms of the core to the number of ... with each other, and thus the Young’s modulus of either core or shell is not the same as that of the isolated nanowire or the isolated nanotube. On the othe...

Ngày tải lên: 16/03/2014, 15:22

... as the pressure of the left upper corner of the loop; the sig- nificance of this pressure will be discussed in detail below. Moving to the bottom of the loop, we can reason that the pressure of ... instantaneous atrial volume). The pressure of the point at the bottom right corner of the loop is the pressure in the ventricle at the end of the car...

Ngày tải lên: 22/02/2014, 09:20

... to the sub-T g secondary transitions). The strength and magnitude of these transitions depends on the de- gree of crystallinity and the size of the lamellae, and therefore is influenced by the thermal ... underlying molecular structure. The influence of other molecular parameters such as molecular weight (chain length) is mainly restricted to the rubber region, wh...

Ngày tải lên: 09/03/2014, 00:20

... effects on Tg. Theoreti-cally. the Tg value .should increase with pressure as a function of the ratio of the compressibility to the- thermal coefficient of expansion of the polymer. Other thermodynamic ... modulus, The maximum in the curve denotes the stress at yield a v and the elongation at yield € v . The end of the curve denotes the failure of the mat...

Ngày tải lên: 22/03/2014, 12:20

... effects on Tg. Theoreti-cally. the Tg value .should increase with pressure as a function of the ratio of the compressibility to the- thermal coefficient of expansion of the polymer. Other thermodynamic ... modulus, The maximum in the curve denotes the stress at yield a v and the elongation at yield € v . The end of the curve denotes the failure of the mat...

Ngày tải lên: 22/03/2014, 13:20

... Inc. Æ À1 ¼1=5boundaryisoneinwhich1in5ofthegrainboundaryatoms match,asshowninFig.2.8(c). Twinboundariesmayformwithincrystals.Suchboundarieslieacross deformationtwinplanes,asshowninFig.2.8(d).Notethattheatomson eithersideofthetwinplanesaremirrorimages.Stackingfaultsmayalsobe formedwhentheperfectstackinginthecrystallinestackingsequenceis disturbed,Figs2.8(e)and2.8(f).Thesemaybethoughtofastheabs...

Ngày tải lên: 23/12/2013, 00:15

... enter into the problem. The engineer must appreciate the relevant aspects of mechanical behavior at the different length scales. Furthermore, the size scale of the structure can affect the mechanical ... that the origin of the unit cell is at the corner of the unit cell [Fig. 1.10(c)]. The sides of the unit parallelepiped also correspond to the cart...

Ngày tải lên: 23/12/2013, 00:15

... least not in the same way as the others. From Table 10, it can be seen that p53R2 possesses a few mutants that behave differently from the rest of the promoters. Of these, amino acid residues 243 and ... minimizing the sum of the individual prediction error percentage for the two classes. Structural modelling and energy calculations The three-dimensional structure...

Ngày tải lên: 18/02/2014, 11:20

... we have shown that the antibacterial ⁄ fungicidal properties of trappin-2 involve the cationic nature of the molecule, as assessed from the salt and heparin dependence of the antimicro- bial ... source of nitrogen [15], thereby competing with the antibacterial effect of trappin-2. However, none of the bacteria tested destroyed trappin-2 in the incubation mixtur...

Ngày tải lên: 18/02/2014, 17:20