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The cadmium (Cd) content of rice grain grown in metal-contaminated paddy soils near abandoned metal mines in South Korea was found to exceed safety guidelines (0.2 mg Cd kg⁻¹) set by the Korea Food and Drug Administration (KFDA). However, current remediation technologies for heavy metal-contaminated soils have limited application with respect to rice paddy soils. Laboratory and greenhouse experiments were conducted to assess the effects of amending contaminated rice paddy soils with zerovalent iron (ZVI), lime, humus, compost, and combinations of these compounds to immobilize Cd and inhibit Cd translocation to rice grain. Sequential extraction analysis revealed that treatment with the ameliorants induced a 50-90% decrease in the bioavailable Cd fractions when compared to the untreated control soil. When compared to the control, Cd uptake by rice was decreased in response to treatment with ZVI + humus (69%), lime (65%), ZVI + compost (61%), compost (46%), ZVI (42%), and humus (14%). In addition, ameliorants did not influence rice yield when compared to that of the control. Overall, the results of this study indicated that remediation technologies using ameliorants effectively reduce Cd bioavailability and uptake in contaminated rice paddy soils.

Graphene field-effect transistor (GFET) biosensors exhibit high sensitivity due to a large surface-to-volume ratio and the high sensitivity of the Fermi level to the presence of charged biomolecules near the...

Effective control over the molecular orientation of pentacene was achieved with copper(i) iodide and results in a change in the functional properties with increases in both visible light absorption and work function.

This work investigates the evolution of structure and morphology of pure and co-evaporated thin films, as a function of pentacene concentration in a solid host of p-terphenyl.

Chiral π-conjugated molecules bring new functionality to technological applications and represent an exciting, rapidly expanding area of research. Their functional properties, such as the absorption and emission of circularly polarised light or the transport of spin-polarised electrons, are highly anisotropic. As a result, the orientation of chiral molecules critically determines the functionality and efficiency of chiral devices. Here we present a strategy to control the orientation of a small chiral molecule (2,2'-dicyano[6]helicene, CN6H): the use of organic and inorganic templating layers. Such templating layers can either force CN6H molecules to adopt a face-on orientation and self-assemble into upright supramolecular columns oriented with their helical axis perpendicular to the substrate, or an edge-on orientation with parallel-lying supramolecular columns. Through such control, we show that low-and high-energy chiroptical responses can be independently 'turned on' or 'turned off'.The templating methodologies described here provide a simple way to engineer orientational control, and by association, anisotropic functional properties of chiral molecular systems for a range of emerging technologies. Main textConjugated organic materials have enabled considerable advances in consumer electronics, in part due to their low cost, tunable optical and electronic properties, and compatibility with flexible, large-area device architectures. The performance of such devices is not only influenced by molecular structure, but how these molecules assemble in the solid state, and how the resultant molecular assemblies are oriented with respect to device-relevant interfaces. Molecular chirality is increasingly recognised as a strategy to expand the functionality of such devices, enabling the realisation of next-generation displays, polarisation selective photodetectors, enantioselective biosensors and room-temperature spintronic devices. [1][2][3][4][5][6] When considering appropriate chiral conjugated small molecule materials for such applications, the archetypal example is the family of fused aromatics called the helicenes.These molecules are comprised of n≥5 ortho-fused angularly arranged benzene rings, which give rise to a non-planar screw-shaped skeleton. [7] The intrinsically chiral and fully conjugated molecular structure of the helicenes affords them outstanding anisotropic chiroptical and charge transport properties, as well as the ability to filter electron spins at room temperature. [8][9][10][11][12][13]

Azatetracene compounds comprise a promising family of n-type semiconductors. Straightforward to synthesise, these materials are compatible with vapour deposition techniques and exhibit π-stacking and hydrogen bonding governed crystal packing.

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