Volume 35, Issue 3

This paper reports the advances in biosorption of trace elements to produce value-added products for agriculture. Innovative fertilizers and dietary feed supplements can be produced by biosorption, where micronutrients are bonded with biological material. The process is controlled by the equilibrium between functional groups and micronutrient ions (e.g., Cu(II), Mn(II), Fe(II), Zn(II)), yielding the products with controlled release properties. The latter assumes high bioavailability and low toxicity to plants and animals. This makes it possible to biofortify food of plant and animal (meat, milk, eggs) origin with microelements and produce a new generation of functional food, rich in microelements. Regulatory issues related with micronutrient dietary feed supplements and fertilizers were discussed. Special attention has been paid to micronutrient deficiencies in plant cultivation and animal nutrition and to the methods of overcoming this problem. The applicability of biosorption to supplement bioavailable form of nutritionally significant elements was discussed. Current developments of biosorption-based technologies for agriculture were presented.

The coordination chemistry of platinum covers a huge field as shown by a recent survey covering the structural parameter of almost 460 dimeric to oligomeric examples. Approximately 10% of these complexes exist as isomers and are summarized in this review. Included are distortion (87%) and cis - trans (13%) isomers. These are discussed in terms of the coordination about the platinum atom, and correlations are drawn among donor atom, bond distance, and interbond angles. Distortion isomers, differing by a degree of distortion in Pt-L and Pt-Pt distances and L-Pt-L angles, and some also by crystal classes, are the most common. Distortion isomers are also spread over a wider range of oxidation states of platinum [0, +1, +2 (most common), +3, +4, and even nonintegral (+2.14 and +2.375)] than cis - trans isomers (+2 and +3 only). Surprisingly, distortion isomerism is more common than the better-known cis - trans isomerism in the chemistry of platinum.

For the past 40 years, titanium dioxide (TiO 2 ) nanomaterials have attracted immense attention because of their potential applications in the photodegradation of organic pollutants, photocatalytic water splitting for H 2 generation, and dye-sensitized solar cells. Despite the fact that the potential applications of TiO 2 nanoparticles are ubiquitous, they are not problem free, examples include a large interfacial area that causes slow charge carrier transport, a wide optical band gap that leads to limited applications using solar light, and single-phase and nanoscales features that induce fast recombination of photo-reduced carriers. Therefore, this review highlights the development associated with the adsorption photocatalysis hybrid system for treating wastewater. The immobilization of TiO 2 photocatalysts in metal oxide, carbon, and ceramic materials to form TiO 2 hybrid systems could prevent the problem of particle recovery, adsorption capacity, and the separation process. Such hybrid systems require significant effort of optimizing the specific surface area-to-volume ratio of the supported photocatalysts with its photocatalytic activities.