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In this work, we utilise the disulphide bond structure of insulin and a new benzothiazole Raman probe for the detection of human insulin using surface-enhanced Raman spectroscopy (SERS). The disulphide bond structure of the insulin was reduced to generate free sulfhydryl terminal groups. When reacted with benzothiazole-functionalised gold nanoparticles, the reduced protein desorbs the Raman probe and causes its Raman signal intensity to quench. Using this approach, insulin was quantified in the concentration range of 1 × 10-14 -1 × 10-8 M by SERS quenching. The limit of quantification of insulin by the SERS quenching method was found to be 1 × 10-14 M (0.01 pM or 58 pg/L), which satisfies the requirements for monitoring its blood concentration in patients. Because many proteins and peptides have disulphide bonds in their molecular structures, the new SERS quenching method has a strong potential for the rapid determination of ultralow concentrations of proteins in formulations and biological fluids.

Product selectivity of alkyne hydroamination over catalytic Au2Co alloy nanoparticles (NPs) can be made switchable by a light-on/light-off process, yielding imine (cross-coupling product of aniline and alkyne) under visible-light irradiation, but 1,4-diphenylbutadiyne in the dark. The low-flux light irradiation concentrates aniline on the catalyst, accelerating the catalytic cross-coupling by several orders of magnitude even at a very low overall aniline concentrations (1.0×10−3 mol L−1). A tentative mechanism is that Au2Co NPs absorb light, generating an intense fringing electromagnetic field and hot electrons. The sharp field-gradient (plasmonic optical force) can selectively enhance adsorption of light-polarizable aniline molecules on the catalyst. The light irradiation thereby alters the aniline/alkyne ratio at the NPs surface, switching product selectivity. This represents a new paradigm to modify a catalysis process by light.

Earth‐abundant and environmentally friendly aluminosilicate minerals can be one of the promising alternatives to develop cost‐effective energy conversion and storage devices. Herein, in situ growth of transition metal nanoparticles is proposed to modify two commonly available feldspar minerals, albite and microcline, for promoting electrocatalytic oxygen evolution reaction activity via a one‐step thermal reduction strategy. Three types of transition metal nanoparticles, namely, Ni, Co, and Fe, are selected to modify the albite or microcline surfaces. As expected, these modified products deliver enhanced catalytic activities compared to the pristine minerals. Particularly, Co‐modified microcline (C‐KASO) demonstrates the best performance that even outperforms the commercial RuO2 catalyst. This design by coupling low‐cost aluminosilicate minerals with active transition metal nanoparticles offers a new insight into directly utilizing the natural abundant resources to address the current energy crisis.

Cyanide (CN−) is one of the most hazardous ions to humans and the environment. Therefore, sensitive, and selective sensors for CN− monitoring are highly required. A novel chemosensor based on naphthalene flanked diketopyrrolopyrrole dye (TBC-DPPN) is synthesized for the direct detection of CN− in water samples by naked eye and vibrational spectroscopy (UV–Vis and fluorescence). The electron deficient carbonyl group of the lactam ring of TBC-DPPN undergoes a nucleophilic attack by the CN− thus causing the yellow color of the dye turn to colorless, and fluorescence of the dye at 527 nm to turn-off. The mechanism of CN− sensing by the TBC-DPPN sensor is confirmed by spectral measurements and density functional theory (DFT) calculations. The TBC-DPPN sensor is utilized to determine the CN− by colorimetric and fluorescence methods in water down to 0.5 and 0.05 µm, respectively, which is well below the cut off limit of 1.9 µm that is recommended by the World Health Organization (WHO). Therefore, TBC-DPPN can act as dual channel sensor with high selectivity and sensitivity for the determination of CN− in water.

The direct use of natural minerals for low-cost energy storage is a promising solution toward large-scale and affordable sustainable energy supply, but it is usually impeded by their inert electrochemical activity. In this work, electrochemically inert albite mineral layered particles are activated as a promising low-cost anode material for electrochemical Li ion storage devices through a facile thermal reduction treatment technology. Via this strategy, partial SiO reduction within the albite mineral particles and a conductive carbon layer on the surface are simultaneously realized, which effectively addresses the issues of inactive lithium storage and poor electric conductivity of albite minerals. Via theoretical density functional theory calculations and molecular dynamics simulations, the activation mechanism of lithium storage achieved by silica reduction is understood. This innovatively activated albite mineral delivers a maximum specific capacity of >250 mAh g based on a dominant surface-driven capacitive storage mechanism, and demonstrates excellent capacity and cycling stability at high charging/discharging rates. This design opens a new pathway to address the current cost issue in energy devices, provides insights into producing cost-effective anodes by using silica-rich minerals, and gives an alternative solution for improving the chemical reactivity of inorganic natural minerals toward low-cost and large-scale energy storages.

Nanostructure engineering has been proved to be an efficient approach for improving electrochemical properties for energy storage by accommodating volume changes, facilitating rapid mass transport paths, and enlarging ion storage sites and interfaces. The well-designed fine nanostructures, unfortunately, are usually destroyed during long-term cycles and ultimately lose their structural advantages. Herein, stimulated by the extraordinary structural stability, robust mechanical properties, and salient ventilation capacity of natural honeycomb species, bioinspired heterogeneous bimetallic Co–Mo oxide (CoMoOx) nanoarchitectures assembled from 2D nanounits are successfully fabricated via a molybdenum-mediated self-assembly strategy for improving the rate capability of electrochemical lithium storage devices. Owing to the robust structural stability and the ultrathin 2D wall structure, CoMoOx nanostructures present well-maintained honeycomb-like structure, rapid capacitive insertion–desertion behaviors, and thus significantly enhanced lithium ion storage performance at high rates (5.0 A g−1). It is also revealed that the reversible transition of cobalt and molybdenum phases closely associated with the ultrathin 2D wall structures greatly contribute to the outstanding electrochemical lithium storage performances. This attractive integration of structural and functional advantages achieved by learning from nature offers new insights into the design of cost-effective electrode materials for high-performance energy devices.

Co-precipitation is a common method for the preparation of layered double hydroxides (LDHs) and related materials. This review article is aimed at providing newcomers to the field with some examples of the types of co-precipitation reactions that have been reported previously and to briefly investigate some of the properties of the products of these reactions. Due to the sheer volume of literature on the subject, the authors have had to limit this article to the synthesis of Mg/Al, Zn/Al and Ca/Al LDHs by co-precipitation and directly related methods. LDHs have been synthesised from various reagents including metal salts, oxides and hydroxides. Co-precipitation is also useful for the direct synthesis of LDHs with a wide range of interlayer anions and various bases have been successfully employed to prepare LDHs. Examples of other synthesis techniques including the urea method, hydrothermal synthesis and various mechanochemical methods that are undoubtedly related to co-precipitation have also been included in this review. The effect of post synthesis hydrothermal has also been summarised.

Raman spectra of phosphuranylite and yingjiangite were measured, interpreted and compared with published infrared spectra of both minerals. U-O bond lengths were calculated using the Bartlett-Cooney‘s empirical relations and the O-H-O hydrogen bond lengths were inferred on the basis of Libowitzky's empirical relation. The presence of oxonium and (H3O)+ ions, expected from the single crystal structure analysis of phosphuranylite, was not inferred from the Raman spectra. It was assumed that phosphuranylite and yingjiangite are identical and the name yingjiangite should be discarded because the name phosphuranylite has priority.

Raman at 298 and 77 K and infrared spectra of two samples of sodium-zippeite were studied and interpreted. U-O bond lengths in uranyl were calculated and compared with those inferred from the X-ray single crystal structure data of a synthetic sodium-zippeite analog. Hydrogen-bonding network in the studied samples is discussed. O-H…O bond lengths were calculated and compared with those predicted from the X-ray single crystal structure analysis.

Uranopilite, \[(UO2)6(SO4)O2(OH)6(H2O)6](H2O)8, the composition of which may vary, can be understood as a complex hydrated uranyl oxy hydroxy sulfate. The structure of uranopilite of different localities has been studied by Raman spectroscopy at 298 and 77 K. A single intense band at 1009 cm-1 assigned to the ￮1 (SO4)2- symmetric stretching mode shifts to higher wavenumbers at 77 K. Three low intensity bands are observed at 1143, 1117 and 1097 cm-1. These bands are attributed to the (SO4)2- ν3 antisymmetric stretching modes. Multiple bands provide evidence that the symmetry of the sulphate anion in the uranopilite structure is lowered. Three bands are observed at 843 to 816 cm-1 in both 298 and 77 K spectra and are attributed to the ν1 symmetric stretching modes of the (UO2)2+ units. Multiple bands prove the symmetry reduction of the UO2 ion. Multiple OH stretching modes prove a complex arrangement of OH groupings and hydrogen bonding in the crystal structure. A series of infrared bands not observed in the Raman spectra are found at 1559, 1540, 1526 and 1511 cm-1 attributed to ￤ UOH bending modes. U-O bond lengths in uranyl and O-H…O bond lengths are calculated and compared with X-ray single crystal structure analysis. Raman spectra of uranopilites of different origin show subtle differences in spectra proving the spectra are origin and sample dependent. Hydrogen-bonding network and its arrangement in the crystal structure play an important role in the origin and stability of uranopilite.

Raman spectroscopy complimented with infrared spectroscopy has been used to study the mineral schroeckingerite. The mineral is a multi-anion mineral and has (UO2)2+, (SO4)2-, and (CO3)2- units in its structure and bands attributed to these vibrating units are readily identified in the Raman spectra. Symmetric stretching modes at 815, 983 and 1092 cm-1 are assigned to (UO2)2+, (SO4)2-, and (CO3)2- units, respectively. The antisymmetric stretching modes of (UO2)2+, (SO4)2- are not observed in the Raman spectra but may be readily observed in the infrared spectrum at 898 and 1180 cm-1. The antisymmetric stretching mode of (CO3)2- is observed in the Raman spectrum at 1374 cm-1 as is also the ν4 (CO3)2- bending modes at 742 and 707 cm-1. No ν2 (CO3)2- bending modes are observed in the Raman spectrum of schroeckingerite. All the spectroscopic evidence points to a highly ordered structure of this mineral.

Raman spectra of two uranyl mineral dewindtite samples are presented and interpreted. Observed bands are attributed to the stretching and bending vibrations of (UO2)2+ and (PO4)3- units and water molecules. Hydrogen bonding network in dewindtite crystal structure is shortly mentioned. U-O bond lengths in uranyls are calculated with empirical relations and wavenumbers of the (UO2)2+ stretching vibrations. These calculations are in agreement with the X-ray single crystal structure data.

A comparative study of the chemical composition, mineralogy, morphology and crushing strengths of fly ash bricks, conventional concrete bricks and fly ash samples has been undertaken. The main chemicals present in the products were silica and alumina while their main minerals were quartz, mullite, illite, vaterite, and calcite. Elemental analysis by XPS showed that the major elements in the samples were oxygen, silicon, carbon, calcium and aluminium; and scanning electron microscopy revealed that the fly ash samples consist of spherically-shaped particles with surface attachment containing needle-like particles. Compared with conventional concrete bricks, fly ash bricks generally have higher atomic silicon and crushing strengths but lower crystalline silica. The implication of the results on the suitability of fly ash bricks as replacements for conventional concrete bricks in the building industry is discussed from the point of view of human health and occupational safety.

The application of multicriteria decision-making methods to the results of in vitro antifungal properties of organotin compounds of the type PhxSnXz (x = 2 or 3; X = O2CC6H4OH, O2CC6H4OCOCH3, Cl or O2CCH3; z = 1 or 2) and of free 2-hydroxybenzoic and 2-acetoxybenzoic acids against Aspergillus niger, Aspergillus flavus, Candida albicans, Penicillium citrinum, Trichophyton rubrum and Trichophyton violaceum have been described. Ranking information necessary to select one toxicant in preference to others and to assess the properties influencing the preference has been obtained. Patterns in the multivariate analyses suggest that cationic and anionic moieties of the toxicant play some roles in their fungicidal activities. The triphenyltin compounds were generally more active than their diphenyltin analogues, but the acetoxybenzoates were more active than the corresponding hydroxybenzoates, acetates or chlorides. Thus, triphenyltin acetoxybenzoate is up to 7.5 times as active as the corresponding acetate, which is commercially marketed as a fungicide. The results of the analyses have been discussed in the light of the mechanism of antifungal activity of organotin compounds and the potential of multivariate data analysis techniques to facilitate the screening and ranking of antifungal agents. Copyright © 2003 John Wiley & Sons, Ltd.

It is crucial that the reaction proceeds under visible light and in the presence of oxygen.

A study by titrimetric methods of the donor strength of pyridine and aniline and some of their para-substituted derivatives, and the J( 119 Sn-C-H) of their adducts with dimethyltin dichloride in nitrobenzene, has shown that the pK b of a Lewis base and its para-substituted derivatives varies linearly with the J( 119 Sn-C-H) of the adducts of dimethyltin dichloride (Me 2 SnC 12 ), with the Lewis base dissolved in an inert solvent. A graphical plot of the pK b of a given series of Lewis bases versus the J(Sn-C-H) of their complexes with Me 2 SnCl 2 in nitrobenzene (at the same temperature, and same complex concentration) gives a straight line with a negative gradient, making possible the deduction of the other parameter (e.g. pK b ) for a Lewis base in the series, where the one parameter (e.g. J(Sn-C-H) is known. The graph for each series of Lewis base has its own characteristic gradient, and the gradients appear proportional in magnitude to the donor strengths of each class of the bases, making it possible to deduce from such graphs which series of Lewis bases are the stronger donors.