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The objective of this study was to find a suitable extractant(s) for plant‐available metals in metal contaminated soils. Swiss chard (Beta vulgaris L. ‘Fordhook Giant’) was grown in greenhouse pots on 46 Ontario soils varying in degree of contamination with metals. The soils had been contaminated with metals to varying degrees over a period of years. After 40 days, the plants were harvested and Zn, Cd, Ni, and Cu concentrations were measured. Each soil was extracted with nine different extractants: aqua regia, 0.01M EDTA, 0.005M DTPA, 0.02M NTA, 0.5N CH3COOH, 1N CH3COONH4, 0.6N HCl + 0.05N AlCl3, (COOH)2 + (COONH4)2, and H2O. Zinc, cadmium, nickel, and copper concentrations in Swiss chard were correlated with the amounts of soil Zn, Cd, Ni, and Cu removed by each extractant. Of the nine soil extractants, CH3COONH4 was the best predictor of plant‐available Zn if only extractable Zn and soil pH were included as independent variables in a regression equation. Acetic acid was the best extractant for prediction of both plant‐available Cd and Ni when soil pH was included in the equation. Attempts to find a suitable soil extractant for plant‐available Cu were unsuccessful.

Highly size-controllable synthesis of free-standing perfectly crystalline silicon carbide nanocrystals has been achieved for the first time through a plasma-based bottom-up process. This low-cost, scalable, ligand-free atmospheric pressure technique allows fabrication of ultra-small (down to 1.5 nm) nanocrystals with very low level of surface contamination, leading to fundamental insights into optical properties of the nanocrystals. This is also confirmed by their exceptional photoluminescence emission yield enhanced by more than 5 times by reducing the nanocrystals sizes in the range of 1-5 nm, which is attributed to quantum confinement in ultra-small nanocrystals. This method is potentially scalable and readily extendable to a wide range of other classes of materials. Moreover, this ligand-free process can produce colloidal nanocrystals by direct deposition into liquid, onto biological materials or onto the substrate of choice to form nanocrystal films. Our simple but efficient approach based on non-equilibrium plasma environment is a response to the need of most efficient bottom-up processes in nanosynthesis and nanotechnology.

The objective of this study was to evaluate various extractants for predicting available Zn in soils. The amount of Zn extracted from 85 soils by four extractants (EDTA, DTPA, EDDHA, and HCl + H2SO4), was related to the Zn concentration in corn (Zea mays L.) grown in the greenhouse for 16 days. The effect of other soil variables was determined by including them in a stepwise multiple regression analysis. EDTA and DTPA extractable Zn were superior to the other two extractants, with r values of 0.607 and 0.603, respectively. Of the soil variables tested soil pH had the greatest effect with an r value of −0.586. The inclusion of pH along with EDTA or DTPA extractable Zn gave R2 values of 0.745 and 0.759, respectively. For a given level of extractable Zn, the Zn content of corn increased with decreasing pH. The most significant finding of this study is the effect of pH on the use of EDTA or DTPA as a measure of available Zn. If these extractants are to be used for soils with pH values below 7.0, the pH must be included to obtain a satisfactory measure of available Zn. The concentration of Cu and Mn in the corn was not closely related to the amount extracted by EDTA or DTPA. It was concluded that these extractants were not suitable for measurement of available Cu and Mn in the soils used in this study.

Polymer grafting from graphitic carbon materials has been pursued for several decades. Unfortunately, currently available methods mostly rely on the harsh chemical treatment of graphitic carbons which causes severe degradation of chemical structure and material properties. A straightforward growth of polyaniline chain from the nitrogen (N)-doped sites of carbon nanotubes (CNTs) is presented. N-doping sites along the CNT wall nucleate the polymerization of aniline, which generates seamless hybrids consisting of polyaniline directly grafted onto the CNT walls. The resultant materials exhibit excellent synergistic electrochemical performance, and can be employed for charge collectors of supercapacitors. This approach introduces an efficient route to hybrid systems consisting of conducting polymers directly grafted from graphitic dopant sites.

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Interest in eco-friendly textile wet processing techniques has increased in recent years due to the increased awareness of environmental issues throughout the world [1]. Cost-effective ecofriendly textile dyeing by using either safe dyes and chemicals with reduced cost or by employing clean treatment is the choice of the day for the textile industry [2]. Textile dyes are organic compounds that bring bright and firm colour to fabric [3]. Reactive dyes are widely used in the textile industry because of their simple dyeing procedure and good stability during the washing process. It is a class

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