Very low density

At very low densities It Is quite easy Co give a theoretical description of thermal transpiration, alnce the classical theory of Knudsen screaming 9] can be extended to account for Che Influence of temperature gradients. For Isothermal flow through a straight capillary of circular cross-section, a well known calculation [9] gives the molar flux per unit cross-sectional area, N, In the form... 

A gas is defined as the state of matter distinguished from solid and liq uid states by very low density and viscosity, relatively great expansion and contraction with changes in pressure and temperature, and the ability to diffuse readily, distributing itself uniformly throughout any container... 

At the end of the 1970s considerable interest developed in what became known as linear low density polyethylenes (LLDPE) which are intermediate in properties and structure to the high pressure and low pressure materials. While strictly speaking these are copolymers it is most convenient to consider them alongside the homopolymers. The LLDPE materials were rapidly accepted by industry particularly in the manufacture of film. The very low density polyethylenes (VLDPE) introduced by Union Carbide in 1985 were closely related. 

The very low density materials (VLDPEs) introduced in the mid-1980s are generally considered as alternatives to plasticised PVC (Chapter 12) and ethylene-vinyl acetate (EVA) plastics (see Chapter 11). They have no volatile or extractable plasticisers as in plasticised PVC nor do they have the odour or moulding problems associated with EVA. Whilst VLDPE materials can match the flexibility of EVA they also have better environmental stress cracking resistance, improved toughness and a higher softening point. 

Metallocene-catalysed very low density polyethylene (m-VLDPE) has become available with densities of as low as 0.903. This is of use for sealing layers of multi-layer films since sealing can commence at lower temperatures than with conventional materials such as LLDPE and EVA (see Section 11.6) with the polymer seal exhibiting both cold strength and hot tack strength. 

The bulk modulus of an ideal SWNT crystal in the plane perpendicular to the axis of the tubes can also be calculated as shown by Tersoff and Ruoff and is proportional to for tubes of less than 1.0 nm diameter[17]. For larger diameters, where tube deformation is important, the bulk modulus becomes independent of D and is quite low. Since modulus is independent of D, close-packed large D tubes will provide a very low density material without change of the bulk modulus. However, since the modulus is highly nonlinear, the modulus rapidly increases with increasing pressure. These quantities need to be measured in the near future. 

Finally, a very low-density form of fibrous silica, W-Si02 has been made by the disproportionation of (metastable) crystalline SiO ... 

In order to explain his experimental results, Rutherford designed a new picture of the atom. He proposed that the atom occupies a spherical volume approximately I0 8cm in radius and at the center of each atom there is a nucleus whose radius is about 10 u cm. He further proposed that this nucleus contains most of the mass of the atom, and that it also has a positive charge that is some multiple of the charge on the electron. The region of space outside the nucleus must be occupied by the electrons. We see from Figure 14-11 that Rutherford s picture requires that most of the volume of the atom be a region of very low density. 

Geomembrane These liners chiefly provide impermeable barriers. They can be characterized as (1) solid waste containment hazardous landfill, landfill capping, and sanitary landfill (2) liquid containment canal, chemical/brine pond, earthen dam, fish farm, river/coastal bank, waste-water, and recreation (3) mining, leach pad and tailing ponds and (4) specialties floating reservoir caps, secondary containment, tunnel, erosion, vapor barrier, and water purification. Plastics used include medium to very low density PE, PVC, and chlorosulfonated PE (CSPE). (The Romans used in their land and road constructions what we call geomembrane.)... 

Very low-density lipoprotein receptor ( VLDLR) and APOE receptor-2 ( APOER2) are two gene family members with redundant functions. They are expressed in neurons of the developing brain and act as cell... 

Abbtvviations apoC-lll, apolipoprotein C-lll apoA-l, apolipoprotein A-l apoA-ll, apolipoprotein A-ll CRP, C-reactive protein VLDL, very low density lipoprotein TG, triglycerides LDL-C, low density lipoprotein cholesterol HDL-C, high density lipoprotein cholesterol. 

Systemic treatment of 13-cis retinoic acid frequently leads to cheilitis and eye irritations (e.g., unspecific cornea inflammation). Also other symptoms such as headache, pruritus, alopecia, pains of joints and bone, and exostosis formation have been reported. Notably, an increase of very low density lipoproteins and triglycerides accompanied by a decrease of the high density lipoproteins has been reported in 10-20% of treated patients. Transiently, liver function markers can increase during oral retinoid therapy. Etretinate causes the side effects of 13-cis retinoid acid at lower doses. In addition to this, generalized edema and centrilobulary toxic liver cell necrosis have been observed. 

Venus Flytrap Module Very Long-chain Acyl-CoA Synthetase Very Low-density Lipoprotein Vesicle... 

By depositing low concns of PETN on foamed polystyrene, Archibald (Ref 47A) obtained very low density expl systems. At an apparent PETN density of 0.09g/cc he found D = 2.05 mm/p sec. D could be varied by changing the PETN concn... 

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