Introduction agents

Protein adsorption has been studied with a variety of techniques such as ellipsome-try [107,108], ESCA [109], surface forces measurements [102], total internal reflection fluorescence (TIRE) [103,110], electron microscopy [111], and electrokinetic measurement of latex particles [112,113] and capillaries [114], The TIRE technique has recently been adapted to observe surface diffusion [106] and orientation [IIS] in adsorbed layers. These experiments point toward the significant influence of the protein-surface interaction on the adsorption characteristics [105,108,110]. A very important interaction is due to the hydrophobic interaction between parts of the protein and polymeric surfaces [18], although often electrostatic interactions are also influential [ 116]. Protein desorption can be affected by altering the pH [117] or by the introduction of a complexing agent [118]. 

The use of hydroxyethyl (also hydroxypropyl) methacrylate as a monomer permits the introduction of reactive hydroxyl groups into the copolymers. This offers the possibility for subsequent cross-linking with an HO-reactive difunctional agent (diisocyanate, diepoxide, or melamine-formaldehyde resin). Hydroxyl groups promote adhesion to polar substrates. 

Direct liquid introduction interface. An interface that continuously passes all, or a part of, the effluent from a liquid chromatograph to the mass spectrometer the solvent usually functions as a chemical ionization agent for ionization of the solute. 

The polymerization is carried out at temperatures of 0—80°C in 1—5 h at a soHds concentration of 6—12%. The polymerization is terminated by neutralizing agents such as calcium hydroxide, calcium oxide, calcium carbonate, or lithium hydroxide. Inherent viscosities of 2-4 dL/g are obtained at 3,4 -dianiinodiphenyl ether contents of 35—50 mol %. Because of the introduction of nonlinearity into the PPT chain by the inclusion of 3,4 -dianiinodiphenyl ether kinks, the copolymer shows improved tractabiUty and may be wet or dry jet-wet spun from the polymerization solvent. The fibers are best coagulated in an aqueous equiUbrium bath containing less than 50 vol % of polymerization solvent and from 35 to 50% of calcium chloride or magnesium chloride. 

In 1912, however, (201) it was discovered that espundia (American mucocutaneous leishmaniasis) can be cured by tartar emetic. It was soon learned that kala-a2ar (visceral leishmaniasis) and oriental sore (a cutaneous form of the disease occurring in the Middle East) also respond to antimonial therapy, especially when compounds of pentavalent antimony are employed. Treatment of leishmaniasis with the latter type of antimonials is safe and effective in over 90% of the cases (202). In 1918, it was demonstrated that tartar emetic is of value in the treatment of schistosomiasis (203). Pentavalent antimonials proved to be less effective. The introduction of antimony compounds for the treatment of parasitic diseases is undoubtedly one of the important milestones in the history of therapeutics (see Antiparasitic agents). 

Introduction The term azeotropic distillation has been apphed to a broad class of fractional distillation-based separation techniques in that specific azeotropic behavior is exploited to effect a separation. The agent that causes the specific azeotropic behavior, often called the entrainer, may already be present in the feed mixture (a self-entraining mixture) or may be an added mass-separation agent. Azeotropic distillation techniques are used throughout the petro-... 

A large number of silylating agents exist for the introduction of the trimethylsilyl group onto a variety of alcohols. In general, the sterically least hindered alcohols are the most readily silylated, but these are also the most labile to hydrolysis with either acid or base. Trimethylsilylation is used extensively for derivatization of... 

---