Low wettability

Hence the wood, especially the wood surface (including the interface to the bond line), plays an crucial role for the quality of bonding and hence for the quality of the wood-based panels. Low or even no bonding strength can be caused by unfavorable properties of the wood surface, e.g. due to low wettability. 

Nonstickiness, low friction, low wettability, and high thermal- and chemical-resistance are the major properties of PTFE, which was accidentally discovered in the DuPont laboratories in 1938, and these properties are more or less typical of other fluoropolymers that have been developed since. 

Thus, the strong C—F bond, the special arrangement of atoms in macromolecule, and low surface energy impart some unique physical properties to PTFE and other fluoropolymers high chemical and thermal resistance, nonstick character, low friction coefficient, and low wettability. This combination of properties... 

The DS has a strong influence on the hydrophobic character of the modified starches and, as expected, increasing the DS decreases the polarity of the surface. For DS > 0.1, contact angles are greater than 90° with quite a low total surface energy, indicating a significant hydrophobicity of the material and a low wettability as previously reported for esterified starches [74-76]. 

In conU ast to the internal surface reversed-phases described above, Kima-ta s internal surface reversed-phases are synthesized without use of enzymes. These Ci, Cg, Cig, and phenylethyl-modified porous silica supports are treated with HCI at 100 C for 5 h to cleave preferentially the ester bonds at the external surface (127). Hydrolysis inside the pores is extfemely slow because of hydrolysis products that are enriched in the pores, low wettability, and the presence of air bubbles. The generated silanol groups are reacted with 3-glycidoxypropyl-trimethoxysilane, which is then hydrolyzed to hydrophilic diol groups. Several variations of Kimata s supports with different hydrophobicity exist, so these phases can be used for analyzing a broad spectrum of analytes. 

Development of a Robust Formulation of Low Wettability Drug during Early... 

Case Study—The Choice of Capsule or Tablet Formulation for Early Clinical Trials Involving Low Wettability Drug... 

Because of the high chemical inertness of PTFE to the majority of industrial chemicals and solvents and its low wettability, it absorbs only small amounts of liquids at ambient temperatures and atmospheric pressure.37... 

Screen mesh wicks have a moderate capillary pumping head, but have low permeability and high effective thermal resistance. Have low wettability after the dry-out. 

In RP-TLC, silica gel plates impregnated with a strong hydrophobic agent (paraffin oil or silicone oil, usually 5%) have been extensively used in the past as nonpolar stationary phases. Nowadays, plates covered with octa-decyl-silanized (ODS) silica gel are available. In this material, the silanol groups are etherified with alkyls containing 8 (Cg) or 18 (Cig) carbon atoms. The low wettability of HPTLC plates coated with highly etherified silica gel poses limitations in the water content of the mobile phase. This problem is circumvented by the use of RP-Cig plates with 50% etherification. However, the presence of free silanol groups may lead to undesirable silanophilic interactions, especially with low water content in the mobile phase. 

The factors described earlier that affect the solubility of a lead compound when choosing a particular salt form—a polymorphic form—a specific crystalline form directly affects the most critical parameter that determines the drug activity, which is the dissolution rate in the biological milieu. The first step in the commencement of dissolution is the wettability of solid particles—there is a direct correlation between wettability and bioavailability. As the milieu of drug administration sites is mostly aqueous in nature, low wettability makes the particles less hygroscopic. 

The relatively high separating efficiency of packings made of plastic material with a low wettability is interpreted by Teller [138] as resulting from the formation of an interstitial hold-up due to the low energies of adhesion involved c,f. chap. 4.2). This hold-up extends the residence time of the liquid phase in the column. Teller s polyethylene Tellerettes (Fig. 356) yield a relative free vohune of 83%. They are shaped such that the two phases encounter relatively small solid surfaces by which they are divided and diverted. 

Surface moisture is related to the amount of available surface and the wettability of the coal but moisture contents are lower than might be expected from the available surface area because of the low wettability of coal compared with the surfaces of minerals. Surface moisture can be removed from washed higher-rank (bituminous and anthracite) coals by drainage on a screen while the dewatering of washed small coal or coal fines can be accomplished by the use of cyclones or centrifuges. If the moisture content must be reduced to lower levels, there are two alternate methods which involve the use of rotary kilns or fluidized bed dryers. But, such dried coal will reabsorb moisture on exposure to the atmosphere which may give rise to fire hazards as well as explosion hazards. 

Extremely high rates of temperature change (10 K/s) show that it is possible to intermpt the methane cracking chain before solid carbon is produced from acetylene. Thus the problem of coke formation can be eliminated. In any case possible formation of coke in liquids is not so detrimental problem as in the conventional hydrocarbon crackers - in view of low wettability in many liquids coke could be relatively easier separated. 

PLLA originally has low wettability and poor compatibility to cells due to its hydrophobicity. Therefore, some attempts have been made to solve this problem by irradiation, such as ionized beam irradiation [28], UV/ozone irradiation [29], or oxygen radio frequency glow discharge [30]. Moreover, it is also effective to reconstruct the surface of PLLA chemically with hydrophilic molecules. UV-induced graft polymerization with hydrophilic monomers and additives can enhance the wettability and cytocompatibility [31-36]. 

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