Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Secondary stiffness

Column drift ratio at recoverability limit Column drift ratio at end point of secondary stiffness... [Pg.525]

Radiation Effects. Polytetrafluoroethylene is attacked by radiation. In the absence of oxygen, stable secondary radicals are produced. An increase in stiffness in material irradiated in vacuum indicates cross-linking (84). Degradation is due to random scission of the chain the relative stabiUty of the radicals in vacuum protects the materials from rapid deterioration. Reactions take place in air or oxygen and accelerated scission and rapid degradation occur. [Pg.352]

The design states that the roll must not deflect by more than 0.01 mm at its centre. To achieve this bending stiffness, each roll is to be backed up by one secondary roll as shown in Fig. 14.9(b). Calculate the secondary roll radius needed to meet the specification. The central deflection of the secondary roll is given by... [Pg.157]

Here / is the fraction of stiff, covalent bonds (modulus Ej) and 1 - / is the fraction of weak, secondary bonds (modulus E2). The polymer modulus is... [Pg.240]

The four primary coolant pumps are connected to the secondary shield wall by three-link snubbers designed to be flexible under static applied loads (thus, allowing thermal expansion) but become stiff under dynamic loads that might occur during an earthquake. Accordingly, the system is coupled to the wall under seismic loading. [Pg.191]

Stiffness The same factors that influence thermal expansion dictate the stiffness of plastics. Thus in a TS the degree of cross-linking and amount of overall flexibility are important. As an example, in a TP its crystallinity and secondary bond s strength control its stiffness. [Pg.318]

Low sensitivity to lateral decenters (hence to gravity, wind and thermal excitations), the alignment of the primary and secondary mirrors being quite inconsequential, and stiffness at the location of the critical subsystem (the corrector) being fairly high ... [Pg.76]

Signs The first symptoms consist of darker green streaks in a pattern of "dots" and "dashes" ("Morse code" streaking) on the lower portion of the midrib. Later, the streaks appear on the secondary veins of the leaf and then on the leaf blade. Suckers that develop after infection are usually severely stunted, which causes the leaves at the top of the stem to become bunched. Leaves are usually short, stiff, erect, and more narrow than normal. Severely infected banana plants usually will not fruit. If the plant does bear fruit, it will likely be distorted and twisted. [Pg.535]

An adjunct for the relief of skeletal muscle spasm caused by reflex spasm to local pathology (such as inflammation of the muscles or joints, or secondary to trauma) spasticity caused by upper motor neuron disorders athetosis stiff-man syndrome. Injectable diazepam may also be used as an adjunct in tetanus. [Pg.1285]

For a semi-crystalline polymer the E-modulus shows between Tg and (in which region it is already lower than below Tg), a rather strong decrease at increasing T, whereas with amorphous polymers, which are used below Tg, the stiffness is not much temperature dependent (apart from possible secondary transitions). The time dependency, or the creep, shows a similar behaviour. [Pg.22]

Oldham discovered that there are actually two kinds of seismic vibrations, one called P (or "primary," because it travels faster and arrives first) and the other called S (or "secondary," because of its later arrival at the same station). The compressional motion of the P waves can be transmitted through most substances, although the speed at which the wave moves decreases as the stiffness of the medium decreases. In contrast, the transverse motion of S waves cannot be transmitted through a liquid, because the loosely bonded molecules in a liquid slip past each other too easily. S waves are observed to disappear at the top of the core. Then, at a depth of approximately 5100 km, the P wave velocity abruptly increases and there is a hint of the reappearance of an S wave. From such observations, Danish geophysicist Inge Lehman hypothesized in 1936 that the core was stratified, with an outer liquid portion and an inner solid portion. The existence of molten metal at core pressures requires some light element to act as antifreeze. [Pg.219]

Secondary symptoms Headache, stiffness of the neck and back, general pain, blocked nose, runny nose, sneezing, shortness of breath, cough. [Pg.38]

Secondary symptoms Shakiness, stiffness of muscles, dry mouth, indigestion, vigilance, quick breathing, night sweats, tiring easily and quickly. [Pg.300]

Plasticization is the process in which the plasticizer molecules neutralize the secondary valence bonds, known as van der Waal s force between the polymer molecules. It increases the mobility of the polymer chains and reduces the crystallinity. These phenomena become evident in reduced modulus or stiffness, increased elongation and flexibility, and lowering of the brittle or softening temperature of the plasticized product. The effect of plasticizers on polymers is the subject of the first chapter by E. H. Immergut and H. F. Mark. [Pg.5]

There are many further issues that can be addressed by the model of the kind described here. Clearly, the HA model is amenable to a number of generalizations that allow one to study more sophisticated features of amphiphilic copolymers, including, for instance, backbone stiffness, orientational degrees of freedom, or additional structural constraints such as the saturation of monomer-monomer interactions [98], which are crucial, e.g., for the folding of RNA. Also, it is easy to introduce dipole moments for side H - P bonds and specific directional interactions (like hydrogen bonds) for some of the chain units. These additional factors can result in the formation of intramolecular secondary structures and lead to an increase in the stability of globules formed by such polymers. [Pg.50]


See other pages where Secondary stiffness is mentioned: [Pg.512]    [Pg.524]    [Pg.512]    [Pg.524]    [Pg.233]    [Pg.433]    [Pg.6]    [Pg.14]    [Pg.157]    [Pg.123]    [Pg.50]    [Pg.366]    [Pg.30]    [Pg.399]    [Pg.78]    [Pg.79]    [Pg.81]    [Pg.3]    [Pg.220]    [Pg.103]    [Pg.185]    [Pg.187]    [Pg.384]    [Pg.170]    [Pg.75]    [Pg.575]    [Pg.145]    [Pg.57]    [Pg.202]    [Pg.433]    [Pg.365]    [Pg.226]    [Pg.226]    [Pg.197]   
See also in sourсe #XX -- [ Pg.512 ]




SEARCH



Stiff Stiffness

Stiffness

© 2024 chempedia.info