Showing papers by "Annamalai University published in 1986"

13C and 1H NMR spectral studies of some piperidin-4-one oximes

Abstract: 13C NMR spectra have been recorded for eleven piperidin-4-one oximes and for seven of them 1H NMR spectra have been recorded at 270 MHz The effect of oximation on the NMR chemical shitts is discussed The conformations of the oximes are also discussed, based on the observed chemical shifts Although several oximes appear to adopt a chair conformation, in the same manner as the corresponding ketones, the oximes of 3,5-dimethyl-2,6-diarylpiperidin-4-ones with cis-methyl groups seem to adopt an asymmetric non-chair conformation Analysis of the chemical shifts of cis-2,6-dimethylcyclohexanone oxime suggests that this compound also exists in a non-chair conformation, and not in a chair conformation with two axial methyl groups as suggested previously

On the karyological characteristics of some members of Balsaminaceae.

Abstract: Critical karyotype analyses have been carried out in 23 taxa of Balsaminaceae. The karyotypes are reminiscent of the Carex pattern indicating the operation of aneuploidy in the chromosome evolution of this family. It is suggested that secon-dary basic numbers such as 7, 9 and 10 have evolved from a primary basic number of x=8. This has led to the carving out of a probable model of chromosome phylogeny.Hydrocera stands aloof in view of its distinctive karyotype and circumscribed distribution. The chromosome physiognomies of Impatiens leschenaultii and I. latfolia are an index of their intimate affinity.The significant role of karyological inquiry in the assessment of phylogenetic kinship has been indicated.

Enteric luminous microflora of the pond-cultured milk fishChanos chanos (Forskal).

Abstract: Qualitative and quantitative investigations were made on the luminous bacteria associated with the gut of pond cultured milk fishChanos chanos. Significant differences in luminous bacterial numbers were found between gut and pond water and between gut and pond sediment, but not between pond water and sediment. No significant variation in luminous bacterial population among the gut regions was observed. The quantity of ingesta in the fish gut does not appear to influence the biomass of luminous bacteria.Vibrio harveyi andV. fischeri were the 2 most commonly encountered species, and of the 2 luminous species,V. harveyi was predominant.

Low cost plastic suction type greenhouse grain dryer

Abstract: This paper describes a low cost plastic suction type greenhouse grain dryer which has been designed, fabricated and tested by the Annamalai University under an Indo-US Collaborative Research project. The dryer has been used for drying of paddy. It is a portable dryer, the need for which is also discussed. The details of the collector and dryer including the selection of materials and the economic analysis comparing this improved solar drying system with conventional open yard drying are given.

Karyotaxonomy of South Indian Balsaminaceae

Abstract: Cytological studies with special reference to karyotaxonomy have been made in 14 taxa First record of chromosome numbers has been made in 4 species and in the rest of the taxa studied, the present report confirms the earlier observations The chromosome numbers determined in the present study range from 2n=6 to 2n=44 The karyotype analyses show that each taxa has a distinct karyotype of chromosomes Even the closely related species of a genus with same chromosome number have distinct karyotype of chromosomes indicating the karyotype alterations of chromosomes playing important role in speciation

A preemptive priority queue with a general bulk service rule

Abstract: Etude d'un systeme d'attente a un seul serveur avec priorite, constitue par deux types d'unites, avec des entrees de Poisson illimitees et des temps de service exponentiels

Some observations on the biology of periwinkleLittorina scabra scabra (Linne 1758)

Abstract: Reproductive behaviour inLittorina scabra (Linne 1758) was studied from Porto Novo jetty area and observations were made both in natural habitat and laboratory condition. Copulation was observed throughout the year whenever moisture was abundant. It lasts usually 30–50 min and pairs remain together for several hours after copulation has been completed. Copulation was correlated with lunar phase. Breeding inLittorina scabra was observed throughout the year and spawning occurs during high tide of the newmoon and fullmoon. It is concluded that the breeding cycle completes within two weeks. There is no correlation between the number of offspring and the size of the individual. The first indication of sex cells appear in males and females at the size of 9·02 mm and 8·7 mm respectively. This result indicates that male matures before females. Sex-ratio ofLittorina scabra was 1∶1·44 which showed fluctuation when considered month-wise. Mean shell height of male and female were equal. The development was normal in the salinity ranges of 28–30% and at the temperature of 30°C. The veliger emerged out of the egg at 96 hr after the cleavage has started.

Effect of zinc on zoeal development of the estuarine hermit crabClibanarius olivaceus (Henderson)

Abstract: The 96 h LC50 value for zinc was 100 ppb. Larvae reared in 7 sublethal (1, 5, 10, 30, 50, 70, 90 ppb) and 96 h LC50 level concentrations (100 ppb) showed survival rates more than 10%, thus perfectly fitting in with definition of chronic concentration. Survival rate of larvae decreased with increase in test concentration but in the different chronic test concentrations, the overall time required for the completion of zoeal development did not differ significantly from that of control.