Substrate penetration into

Absorption. Some inks (eg, oil-based newspaper inks) dry by penetration or absorption into the pores of the printed stock, which has a blotter or sponge effect. This is accompHshed by the gross penetration of the ink vehicle into the pores of the substrate, the partial separation of the vehicle from the pigment, and the diffusion of the vehicle throughout the paper. The abiHty of an ink to penetrate into paper depends on the number and size of the air spaces present in the paper, the affinity or receptivity of the stock for the ink, and the mobiHty of the ink. 

Stamp-Pad Inks. These inks are impregnated into a cloth or foam mbber pad and transferred by pressure to mbber type which is then stamped or impressed against the substrate. The inks must be completely nondrying in the pad and yet dry by rapid penetration into the paper. Since it is desirable that the total ink soak into the stock, dyes are used rather than pigments. The vehicles used are usually glycols. 

Toners and Tinted Sealers. These materials are usually pigments dispersed in nonpenetrating lacquers. In some instances, solvent or spirit dyes can be used to improve clarity. The soHds of the vehicle can be adjusted to control the depth of penetration into the substrate. 

The viscosity of an adhesive directly influences its penetration into a substrate as the viscosity increases, the penetrating power decreases. It also determines the amount of mileage or spread that can be obtained. An optimum viscosity exists for each substrate and each set of machine conditions and must be achieved in order to manufacture an efficient adhesive. Poly(vinyl acetate) emulsions are frequently too low in viscosity to be metered efficiently or to perform well as adhesives by themselves. They must be bodied to working viscosities, eg, by adding thickeners. 

Fillers are added to emulsion adhesives to build the total soflds content, to reduce penetration into a porous substrate, and to lower costs. 

As previously discussed, the JKR theory predicts that the detachment force is independent of the Young s modulus. Yet despite that, when Gady et al. [117] measured the detachment force of polystyrene particles from two elastomeric substrates having Young s moduli of 3.8 and 320 MPa, respectively, they found that the detachment force from only the more compliant substrate agreed with the predicted value. The force needed to separate the particle from the more rigid substrate was about a factor of 20 lower. Estimates of the penetration depth revealed that the particles would penetrate into the more compliant substrate more deeply than the heights of the asperities. Thus, in that case, the spherical particle approximation would be reasonable. On the other hand, the penetration depth... 

One of the most common rubber adhesives are the contact adhesives. These adhesives are bonded by a diffusion process in which the adhesive is applied to both surfaces to be joined. To achieve optimum diffusion of polymer chains, two requirements are necessary (1) a high wettability of the adhesive by the smooth or rough substrate surfaces (2) adequate viscosity (in general rheological properties) of the adhesive to penetrate into the voids and roughness of the substrate surfaces. Both requirements can be easily achieved in liquid adhesives. Once the adhesive solution is applied on the surface of the substrate, spontaneous or forced evaporation of the solvent or water must be produced to obtain a dry adhesive film. In most cases, the dry-contact adhesive film contains residual solvent (about 5-10 wt%), which usually acts as a plasticizer. The time necessary... 

It is of interest that the activation of POs often takes place in stomata guard cells, since P. infestans mainly penetrates into plant tissues through stomata slits. The localisation of phenolic compounds - some of them seemingly being used by POs as a substrate - and PO activity was visible in guard cells. (Maksimov et al., 2011). As such, the immune reaction occurred in close proximity to pathogen structures. 

Incorporation of Metal In certain cases, metal atoms, after their discharge, can penetrate into the substrate metal, forming alloys or intermetallic compounds in the surface layer and down to a certain depth. This effect has been known for a long time in the discharge of metals at liquid mercury, where liquid or solid amalgams are formed. In 1968 B. Kabanov showed that an analogous effect is present in metal ion discharge at many solid metals. 

In view of the immense commercial importance of phthalocyanines as pigments, it is perhaps surprising that only a few are of importance as textile dyes. This is primarily due to the size of the molecules they are too large to allow penetration into many fibres, especially the synthetic fibres polyester and polyacrylonitrile. An example of a phthalocyanine dye which may be used to dye cellulosic substrates such as cotton and paper is C. I. Direct Blue 86 (96), a disulfonated copper phthalocyanine. In addition, a few blue reactive dyes for cotton incorporate the copper phthalocyanine system as the chromophoric unit (Chapter 8). 

From the frequency measurements of the LB-film-deposited QCM plate in water, the behavior of phospholipid LB films can be classified into three types (i) phospholipids having relatively hydrophilic head groups such as DPPC and DPPG are hydrated and then easily flaked from the substrate in the fluid liquid crystalline state above Tc (ii) DPPE and DPPS having the less hydrophilic head groups are hydrated only near their Tc (iii) cholesterol LB films show relatively large hydration behavior even at low temperatures due to the water penetration into the structure defects in the membrane. 

Though drugs appear to cross the blood-brain barrier by passive diffusion, transporter systems in the blood-brain barrier pump drugs back out into the systemic circulation. As in the gut, the Pgp transporter system is the primary active transporter in the blood-brain barrier identified to date. This ATP-dependent transporter system picks up substrates that have crossed the capillary endothelial cells and transports them back to the systemic circulation, limiting their penetration into the CNS. Thus, not only are the physicochemical properties of the drug a determinant for penetration into the CNS but penetration also depends on whether the drug is a substrate for the Pgp transporter system. 

In our previous study a novel method was developed to prepare a protein-based hydrogel, i.e., a Three-Dimensional Nanos-tructured Protein Hydrogel (3-D NPH), which is composed of protein-polymer hybrid nanoparticles (19, 20). The 3-D NPH could be easily prepared by dispensing a protein and polymer mixture on a substrate. Because the analyte proteins could penetrate into the 3-D NPH, the protein array made by 3-D NPH method has tremendously improved sensitivity in detecting protein-protein interactions compared with that of the direct protein immobilization methods (2-D). 

Ultimately, resolution in a sputtering process is limited by ion penetration into the substrate and/or by the range over which momentum can be transferred effectively enough to remove atoms from the sample surface. The diameter from which atoms can be sputtered has been reported to be about 10 nm for incident ion energies up to 12 keV (62). This means that it should be possible to fabricate structures of about 10 nm which also happens to be the size of the smallest ion beam that can be produced with present ion sources. 

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