Fluid matter

Leather. Natural leather is made from hides, which are salted and cured, then taimed. Through the preparing process, useless matter which caimot be taimed, such as outerskin (epidermis) and flesh, are removed, leaving the tme skin (corium). In the tanning process, the fluid matter which maintains the skin in a flexible and moist condition is removed, and there remains nothing but the fibrous portion to be acted on by the tanning chemicals (1-3). 

One can conceive these phenomena only by admitting the existence of a particular fluid, whose accumulation is the cause of heat and whose absence is the cause of cold it is without doubt this fluid which is lodged between the particles of bodies, separates them, and occupies the place they allow between them. With most physicists, I name this fluid, whatever it may be, igneous fluid, matter of heat and of fire... 

Eire. Igneous fluid. Matter of fire and of heat. Dephlogifticated air. 

In extrusion, as well as in many other processes, one deals with the transport of mass, momentum, and energy. Balance equations are used to describe the transport of these quantities. They are universal physical laws that apply to all media (solids and fluids). Matter is considered as a continuum. Thus, the volume over which the balance equation is formulated must be large enough to avoid discontinuities. 

On the combination of the matter of fire with evaporable fluids and on the formation of elastic aliform fluids. Lavoisier supposes that the igneous fluid, matter of fire, heat, and light , is a very subtle fluid which penetrates all bodies and tends to come into equilibrium in them. It does not penetrate them with equal facility. It can exist in a free state or in a fixed state in combination with bodies. He does not mention Black (whose work was unpublished) but only Richmann, de Mairan, Cullen, and Baume Fourcroy says il oublit Black and did not then know of his work (but see p. 427). 

When applying the conservation laws to fluid matter treated as a continuum, the question arises as to the amount of matter to be considered. Typically this decision is based on convenience and/or level of detail required. There is no single choice. Many possibilities exist that can lead to the same useful predictions. The conservation laws of continuum dynamics can be applied to the fluid contained in a volume of arbitrary size, shape, and state of motion. The volume selected is termed a control volume. The simplest is one where every point on its surface moves with the local fluid velocity. It is called a material control volume since, in the absence of diffusion across its interface, it retains the material originally present within its control surface. Although conceptually simple, they are not readily used since they move through space, change their volume, and deform. An analysis of the motion of material control volumes is usually termed Legrangian and time derivatives are termed material or substantial derivatives. 

Applications of NMRI to polymer science were reviewed with examples for imaging of rigid, soft and fluid matter [635]. Further information on the applications of NMR imaging is available in several reviews [632,671] and books [393,627]. 

As a smnmary, in our problem, there is a spatial quantization whenever there is a differential movement and a non-linear interaetion between a moving entity (here fluid) and matter this is not a property of solid (nor fluid) matter by itself it is a collective or cooperative effect. The thermodynamic properties of the solid solution are n st important to predict the overall structure. The quantization condition is derived from the second... 

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