Volume 3, Issue 7 -

The spectroscopic determination of an equilibrium constant is a classic experiment in the general chemistry laboratory curriculum. Here we describe a new version of this experiment, incorporating green chemistry practices into the general chemistry lab curriculum and directly teaching students about the principles of green chemistry. This lab studies the formation of the iron(III) salicylate complex ion, which is a more benign chemical system than the traditional iron(III) thiocyanate complex. A microtiter plate reader is used to reduce sample volumes, also giving students important experience using research-grade instrumentation. In addition, students gain more experience using adjustable manual micropipettors. Students responded positively to the lab, appreciating the green nature of the lab and the introduction of the plate reader, and student comments suggested that this lab successfully introduces green chemistry concepts to the general chemistry curriculum.

With the increased concern for climate change and depletion of fossil fuel resources, there is a growing trend to research and develop technologies that can use renewable biomass as the raw material for synthesizing chemical products. Bark, a largely available forestry biomass residue with attractive chemical compositions, is considered as a promising feedstock. This article summarizes our recent research and development work in deriving bark-derived adhesives and foams and various bark conversion technologies explored. Advantages and disadvantages associated with the conversion technologies and bark-based chemical products are discussed. Some future studies that can further promote commercial applications of these novel bio-based products are presented. These novel bark-derived products have potential to generate higher value return using the low-valued forestry residue materials while increasing the renewable content in the final chemical products for a higher sustainability.

Germanene, germanium version of graphene, is a novel member in the two-dimensional (2D) materials family. In this present study, a theoretical analysis involving optical properties of defected free standing (FS) germanene layer has been performed within density functional theory (DFT) framework. FS buckled germanene exhibits many fascinating and unconventional optical properties due to introductions of adatoms and voids. Arsenic (As), gallium (Ga) and beryllium (Be) are chosen as doping elements. Doping sites (same or different sub-lattice positions) play a crucial role to improve various optical properties. While Be doping, concentrations of Be are increased up to 18.75 % and void concentrations are increased up to 15.62 % (keeping fixed 3.12 % Be concentration). Emergence of several plasma frequencies occur in case of both parallel and perpendicular polarizations for defected germanene layers. Energy positions of peaks corresponding to maximum of imaginary parts of dielectric constants are red shifted for some As and Ga incorporated systems compared to pristine germanene. Absorption spectra peaks are more prominent for Be doped systems rather than void added systems. In addition, conductivity in infrared (IR) region is very high for the Be doped configurations in case of parallel polarization. Along with these, changes in other optical properties like refractive index, reflectivity, electron energy loss spectroscopy etc. are also analyzed briefly in this present study. We hope, this theoretical investigation may be regarded as an important tool to design novel opto-electronic tuning devices involving germanene in near future.

2,3-Dicyanopyrazine based acceptor was combined with a series of well studied donors to obtain donor-acceptor type potential thermally activated delayed fluorescence emitters. Their structural and electronic properties were computed theoretically at the level of density functional theory and time dependent density functional theory with the application of two different hybrid functionals and various basis sets. Almost all of the designed structures were computed to have the potential of being TADF compounds since they possess very narrow singlet-triplet gaps. Indeed, acridine-pyrazine ( 9 ) derivative was calculated to be the best candidate for the purpose among them.

During the last years, the field of photocatalytic decarboxylations has emerged rapidly. Carboxylic acids are inexpensive, non-toxic and renewable starting materials for the synthesis of pharmaceuticals or platform chemicals. The traceless extrusion of CO 2 gives radical intermediates, which react in diverse cross-coupling reactions. Merging photocatalysis with metal catalysis enables even broader substrate scopes or enantioselective reactions. An overview of photocatalytic decarboxylative reactions of different classes of carboxylic acids is given within this chapter.

The chapter introduces risk assessment and examines the basic concepts of risk and hazard, their causes, consequences and probabilities. The methodology of environmental risk assessment including effect assessment, exposure assessment and risk estimation/characterisation is overviewed. Application of risk assessment for chemicals is described with regard to human health and the environment. Some of the commonly used techniques in risk assessments are introduced and illustrated by examples. Environmental risk assessment should provide input to the risk management so well-informed decisions can be made, to protect human health and the environment.