Force main

A dependence of both crystal and impeller material properties as well as the probability of crystal-impeller collision on fine particle generation rate has also been demonstrated. Thus the relative effects of impact, drag and shear forces responsible for crystal attrition have been identified. The contribution of shear forces to the turbulent component is predicted to be most significant when the parent particle size is smaller than a 200 pm while drag forces mainly affect larger crystals, the latter being consistent with the observations of Synowiec etal. (1993). 

For solid surfaces interacting in air, the adhesion forces mainly result from van der Waals interaction and capillary force, but the effects of electrostatic forces due to the formation of an electrical double-layer have to be included for analyzing adhesion in solutions. Besides, adhesion has to be studied as a dynamic process in which the approach and separation of two surfaces are always accompanied by unstable motions, jump in and out, attributing to the instability of sliding system. 

Similar conclusions regarding how high PTFE content decreases the gas permeability and porosity of CFPs (TGP-H-060 and TGP-H-090) were presented by Park et al. [102]. It was also observed and concluded that the main transport mechanism of the water through the DL was shear force or evaporation, instead of capillary forces (main force in CLs). They also showed that a CFP (TGP-H-060) with 15 wt% PTFE had the best performance with relatively dry conditions compared to a thicker paper with the same hydro-phobic content. 

When the polymer wets the solid (0 = 0), polymer films are thermodynamically stable. For 0 > 0 the films are only metastable. When a thin, metastable film is heated above the glass transition temperature, holes start to form spontaneously, usually at small defects. The holes increase in size until only a network of polymer lines is formed which eventually breaks up into individual droplets (Fig. 7.19) [150], The film stability of films with a thickness of 1-100 nm is determined by long-range surface forces, mainly van der Waals forces [151,268, 294,295],... 

A tour-de-force mainly experimental study of the IR spectrum of 1,2-benzyne Radziszewski JG, Hess BA, Jr., Zahradnik R (1992) J Am Chem Soc 114 52... 

These principles are best recognized when studying relatively simple molecular systems that have an ability to exploit weak interactions to create structure. Among many, peptides are the perfect choice for such studies considering their versatility in make up given the 20+ natural and synthetic amino acid residues, and their functional diversity. In addition, the amino acid sequence of the primary structure combined with the ability of forming secondary (3-sheet or a-helix structures provide substantial room for the creation of hierarchical structures based on weak intermolecular forces, mainly hydrogen bonds. A limited sequence of residues also prevents additional complication from tertiary and quaternary structures as seen with proteins. 

The model employed for the hydration force implies a continuum, even for low separation distances between particles. It was also assumed that the hydration, doublelayer, and van der Waals interactions are additive. The double layer affects the hydration force mainly because of the decrease of the molecular polarizability by large electric fields. However, in the present case, in the vicinity of the surface the electric field due to the double layer is smaller than E by an order of magnitude and hence its influence on the hydration force can be neglected at small separation distances. 

A quantitative treatment of the effects of electrolytes on colloid stability has been independently developed by Deryagen and Landau and by Verwey and Over-beek (DLVO), who considered the additive of the interaction forces, mainly electrostatic repulsive and van der Waals attractive forces as the particles approach each other. Repulsive forces between particles arise from the overlapping of the diffuse layer in the electrical double layer of two approaching particles. No simple analytical expression can be given for these repulsive interaction forces. Under certain assumptions, the surface potential is small and remains constant the thickness of the double layer is large and the overlap of the electrical double layer is small. The repulsive energy (VR) between two spherical particles of equal size can be calculated by ... 

At the request of COLIP A, a task force mainly composed of experts from the cosmetic UV filter producing industry worked to produce a protocol for the determination of the photostability of UV-filters (26). It was their objective to define an in vitro model. 

It is very interesting to note that the virtual-mass force mainly acts through the effective volume coefficient y, and tends to reduce the momenffim-exchange terms. The final step is to use the definitions of the mass-average moments introduced in Chapter 4 to derive the force terms in the macroscale momenffim balance. For the disperse-phase momentum balance (see Eq. (4.85) on page 123), this procedure leads to... 

The only known Tl1 organo compound is the polymeric T1C5H5 precipitated on addition of aqueous TIOH to cyclopentadiene InC5H5 is similar. In the gas phase these compounds consist of discrete molecules having five-fold symmetry. The metal atoms lie over the centers of the rings and are apparently bound by forces mainly of covalent nature. T1C5H5 is a very useful reagent for the synthesis of other metal cyclopentadienyl compounds (Chapter 23). 

L adsorption chimique A laquelle nous avons habituellement affaire en catalyse se diff rencie de I adsorption dite physique par la nature des forces main tenant la molecule adsorb sur la surface de I adsorbant. 

From spring to faU, the intrusion water from the Pacific is narrowly confined to the continental slope south of China, only in winter, when the northeast monsoon becomes fully developed, can it spread in the southern South China Sea. The seasonal cycle over most of the SCS basin is determined predominantly by the regional dynamics within the SCS, and is forced mainly by smface wind stress curl on baroclinic Rossby waves. Furthermore, the Kmoshio also exerts a significant influence on the SCS. However, the water exchange in the Luzon Strait is very complex. 

The forces acting on two-phase fluids can be divided into tangential and normal components. On the micro- and nanoscales, as shown in Table 1, apair of competitive forces - the viscous force and the interfacial force - becomes dominant. The viscous forces mainly act tangential to the interface elongating it, whereas the interfacial forces act normal to the interface inducing droplet or bubble formation (minimizing the interfacial area). The capillary number is the ratio of these two competitive forces and can be expressed as... 

Low molecular weight species, such as metal ions, can be bound to macromolecules by intermolecular forces, mainly ionic interaction and complex binding, or the combination of both. 

An adhesive mixture is a type of formulation for micronised active substances for inhalation in which the small active substance particles adhere by natural forces (mainly Van der Waals forces) to the surface of much larger carrier (or host) particles. 

Orbit The path, relative to a specified frame of reference, described by the center of mass of a satellite or other object in space, subjected solely to natural forces (mainly gravitational attraction). 

Fig. 6.14 Branching paths of the total energy lower than the barrier height. The width of the paths is depicted so as to be proportional to the square root of the electron population on each path. The paths in red (black) are driven by the forces mainly coming from the ground (excited) state. (Reprinted with permission from K. Yamamoto et oL, J. Chem. Phys. 140, 124111 (2014)).

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