Extraction spectrophotometric determination of maneb with 1-(2'-pyridylazo)-2-naphthol (PAN).
A rapid, sensitive, simple and selective spectrophotometric method has been developed for the determination of micro-quantities of maneb (manganese ethylenebisdithiocarbamate) after extraction of the manganese-PAN complex in isobutyl methyl ketone (MIBK). The complex absorbs strongly at 550 nm. Beer's law is obeyed over the concentration range 0.37-3.75 microg/ml. The molar absorptivity was found to be 4.1 x 10(4) l. mole(-1) . cm(-1). The developed method has been applied to the determination of maneb in commercial formulations, synthetic mixtures, grain and in the presence of various other dithiocarbamates.
Fourth Derivative Spectrophotometric Method for the Determination of Fungicide Maneb Using Sodium Molybdate
A highly sensitive fourth derivative spectrophotometric method is presented for the residue analysis of ethylenebis dithiocarbamate fungicide Maneb. The fungicide maneb forms a blue complex with sodium molybdate on heating which is studied spectrophotometrically. The method has been successfully applied to maneb determination in wheat grains and soft drinks with high recoveries. The analytical sensitivity of the present method has been found to be 0.0011 μg/mL.
The Limits of Vulnerability in Explaining Fear of Crime: A Comparative Neighborhood Analysis
Recent research on the fear of crime in the United States has focused on the sources of fear. Many of these studies have identified neighborhood-level variables that are related to fear, but most have examined the differences in fear among individual residents of one or more cities. There has been substantially less research on the differences in the sources of fear among residents of different areas within a single city. This article examines the causes of fear through a comparative analysis of three different neighborhoods in San Francisco. An analysis of covariance model is used to assess the importance of differences in the sources of fear that may be associated with an individual's neighborhood of residence. The findings demonstrate that age, as a measure of physical vulnerability previously associated with fear among individuals, is not related to fear in neighborhoods where residents express the greatest general concern about crime. It is concluded that in those urban areas where crime problems are regular features of the neighborhood environment, measures of physical vulnerability are less important in predicting differences in fear among individuals.