Claims improvement

A Japanese patent has claimed improvements in the direct condensation of menadione with phytyl chloride in the presence of a reducing metal such as 2inc or iron powder (30). Tin chloride has been reported to be a useful catalyst for this condensation (31,32). 

A Belgian patent (178) claims improved ethanol selectivity of over 62%, starting with methanol and synthesis gas and using a cobalt catalyst with a hahde promoter and a tertiary phosphine. At 195°C, and initial carbon monoxide pressure of 7.1 MPa (70 atm) and hydrogen pressure of 7.1 MPa, methanol conversions of 30% were indicated, but the selectivity for acetic acid and methyl acetate, usehil by-products from this reaction, was only 7%. Ruthenium and osmium catalysts (179,180) have also been employed for this reaction. The addition of a bicycHc trialkyl phosphine is claimed to increase methanol conversion from 24% to 89% (181). 

Preparation.- Patents have appeared which claim improved procedures for the synthesis of aryldichlorophosphines and diarylchlorophosphines from aromatic hydrocarbons, phosphorus... 

Various carboxylic acid salts have also been reported. Gallardo35 produced the maleate salt of neomycin which, it was claimed, improved the aqueous stability of the antibiotic. A practically tasteless compound, the citrate salt,has been described by Szyszka3 . Neomycin mandelate has been claimed to be particularly useful in the treatment of urogenital infections3 while the di-hydroxy-dinaphthylmethane-dicarboxylate4(3 and the pamoate salts43,67,68 have a low intestinal absorption and are thus effective treatments for intestinal infections. 

Similarly, fluorescent silver clusters could be prepared in so called molecular hydrogels, formed by polyglycerol-b/oc -poly(acrylic acid) (PG-b-PAA), using a ratio COOH Ag of 2 1 with UV irradiation (365 nm). The emission band centered at 590 nm reached a maximum after 200 min of irradiation. The authors claim improved photostability of the clusters since they are still luminescent even after 9 h of irradiation, but it has to be mentioned that the irradiation source was weak, only 0.5 mW/cm2. They claim that it is the number of arms in the star polymer rather than the length of the arms (thus the density of COOH) that plays a crucial role in the formation of silver clusters [30]. 

The dehydration process may also affect antigen preservation and various special dehydration procedures have claimed improved tissue antigenicity. Similarly, certain types of paraffin, celloidin, and polyethylene glycol have been shown to be useful for immunohistology (Larsson 1993). 

Commercial products that claim improved function owing to their ability to control pH. 

Unlike the thermoplastic polyesters (PBT and PET), the commercial polyamides such as PA-6 or PA-66 are more polar and hence highly immiscible with polycarbonate. Hence simple blends of polyamide and polycarbonate are expected to delaminate readily, unless a suitable compatibiliz-er is used. Because of the lack of an efficient com-patibUization technique, blends of PA-6 (or PA-66) with polycarbonate have not yet reached a commercial significance, although there are several patents claiming improvement in properties. 

The isolation of carotenoids still presents many problems, due in part to the close similarity between isomers differing only in the position or stereochemistry of one double bond. Several reports claim improved methods for the thin-layer chromatographic separation or even gas-chromatographic separation of carotenoids. Analytical methods have been reviewed and extensive tables for the identification of carotenoids published. ... 

Thermite is most eiflcient in its typical manifestations when used without a binder, though two patents claim improvements by binders and other additives. Because of their cooling effect, such tanders, make ignition more difficult and cause heat-flow away from the substratum. Counteracting this by the addition of a stronger oxidizer can partially remedy these faults, but in the end the character of the thermite reaction is lost. 

The other dimension of imperfect state verification in our simulation model is the probability that a worker receives payment for a genuine WC claim. Improved state verification takes the form of an increase in the state verification parameter, i2, the likelihood of receiving WC benefits for a genuine work-related injury. The improvements in f/2 that we simulate and tabulate in Table 5-3 include 10 and 20 percent improvements as well as the elimination of imperfect state verification (v /2 = 1.0). The economic effect of raising j/2 is a shift of the burden of serious injuries away from workers toward firms. 

The most important properties developed by many phosphorus-modified polymers are increased flame resistance and thermal stability (see below). Other claimed improvements include crease resistance, better uptake of dyestuffs, and rotproofing. 

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