A preliminary investigation into the use of ochre as a remedial amendment in arsenic-contaminated soils

Ochre is an unwanted waste product that accumulates in wetlands and streams draining abandoned coal and metal mines. A potential commercial use for ochre is to remediate As contaminated soil. Arsenic contaminated soil (605 mg kg(-1)) was mixed with different ochres (A, B and C) in a mass ratio of 1:1 and shaken in 20 mL of deionised water. After 72 h As concentration in solution was ca. 500 mu g kg(-1) in the control and 1-2.5 mu g kg(-1) in the ochre treated experiments. In a second experiment soil:ochre mixtures of 0.05-1:1 were shaken in 20 mL of deionised water for 24 h. For Ochres A and C, as Solution concentration was reduced to ca. 1 mu gkg(-1) by 0.2-1:1 ochre:soil mixtures. For Ochre B, as concentration only reached ca. 1 mu g kg(-1) in the 1:1 ochre:soil inix. Sorption of As was best modelled by a Freundlich isotherm using As sorption per mass of goethite in the ochre (log K= 1.64, n = 0.79, R-2 = 0.76, p <= 0.001). Efficiency of ochre in removing As from solution increased with increasing total Fe, goethite, citrate dithionite extractable Fe and surface area. (c) 2005 Elsevier Ltd. All rights reserved.

The relationship between phonological awareness and word reading accuracy in Oriya and English: A Study of Oriya-speaking fifth-graders

This study investigated the relationships between phonological awareness and reading in Oriya and English. Oriya is the official language of Orissa, an eastern state of India. The writing system is an alphasyllabary. Ninety-nine fifth grade children (mean age 9 years 7 months) were assessed on measures of phonological awareness, word reading and pseudo-word reading in both languages. Forty-eight of the children attended Oriya-medium schools where they received literacy instruction in Oriya from grade 1 and learned English from grade 2. Fifty-one children attended English-medium schools where they received literacy instruction in English from grade 1 and in Oriya from grade 2. The results showed that phonological awareness in Oriya contributed significantly to reading Oriya and English words and pseudo-words for the children in the Oriya-medium schools. However, it only contributed to Oriya pseudo-word reading and English word reading for children in the English-medium schools. Phonological awareness in English contributed to English word and pseudo-word reading for both groups. Further analyses investigated the contribution of awareness of large phonological units (syllable, onsets and rimes) and small phonological units (phonemes) to reading in each language. The data suggest that cross-language transfer and facilitation of phonological awareness to word reading is not symmetrical across languages and may depend both on the characteristics of the different orthographies of the languages being learned and whether the first literacy language is also the first spoken language.