Two procedures for the synthesis of benzo-21-crown-7 have been explored. The [1+1] macrocyclization with KBF₄ as the template was found to be more efficient than the intramolecular macrocyclization without template. Pseudorotaxanes form with secondary ammonium ions bearing at least one alkyl chain narrow enough to slip into the crown ether. Substitution on benzo-21-crown-7 or on the secondary a...

The extent of female multiple mating (polyandry) can strongly impact on the intensity of sexual selection, sexual conflict, and the evolution of cooperation and sociality. More subtly, polyandry may protect populations against intragenomic conflicts that result from the invasion of deleterious selfish genetic elements (SGEs). SGEs commonly impair sperm production, and so are likely to be unsucc...

In recent years, by population expansion and consequently expansion in service industries, competition has grown in retailing industry more than ever. Retailers can overcome competition in retailing industry by creating attractive, enjoyable, and even more exciting store environment. The purpose of this study is to help marketers, managers and retailers to create an enjoyable and memorable expe...

The crown-ether coordination compounds ZnX2(18-crown-6), EuX2(18-crown-6) (X: Cl, Br, I), MnI2(18-crown-6), Mn3Cl6(18-crown-6)2, Mn3I6(18-crown-6)2, and Mn2I4(18-crown-6) are obtained by ionic-liquid-based synthesis. Whereas MX2(18-crown-6) (M: Zn, Eu) show conventional structural motives, exhibit unusual single MnX4 tetrahedra coordinated to the complex. Surprisingly, some outstanding photolum...

A fractured coronal tooth structure beneath an intact crown is a common clinical occurrence. If the underlying root is healthy, the tooth is restored with a post and core followed by refabrication of the crown. This paper describes a technique of using the existing intact crown for the above-mentioned situation. A 34-year-old female was referred with a fractured right canine with an intact crow...

The benefits of financial development to economic growth are conspicuous, but due the heterogeneity across regions and firms, effects competition have not been fully proved. There is a puzzling phenomenon in many developing countries, that is, banking monopoly coexists with growth. This study uses industrial enterprise data analyse how affects firm total factor productivity (T.F.P.) influence s...