Cd-Al/C layered double hydroxide (Cd-Al/C-LDH) and Cd-Sb/C nanocatalyst are reported here for the de-coloration and mineralization of organic dyes. These catalysts were largely characterized by FESEM, EDS, XRD, FTIR, XPS, PL and DRS. The diffuse reflectance data showed a band gap at 2.92 and 2.983 eV for Cd-Al/C-LDH and Cd-Sb/C respectively. The band gap suggested that both catalysts work well in visible range. The photoluminescence spectra indicated a peak at 623 nm for both the catalysts which further support the effectiveness of the respective catalyst in visible range. Both catalysts also showed good recyclability and durability till 4<sup>th</sup> cycle. Five dyes, acridine orange (AO), malachite green (MG), crystal violet (CV), congo red (CR) and methyl orange (MO) were used in this experiment. Various parameters of different light intensity such as visible, ultraviolet, sunlight and dark condition are observed for the de-coloration of these dyes. The de-coloration phenomenon was proceeded through adsorption assisted phot-degradation. The low cost, abundant nature, good recyclability and better dye removal efficiency make these catalysts suitable candidates for the de-coloration and mineralization of organic dyes.
In the title compound, C(19)H(17)NO(4)S, the phenyl ring and the naphthalene ring system are oriented at a dihedral angle of 4.12 (2)° and the mol-ecule adopts a U-shaped conformation. The C(c)-C-N-S (c = carb-oxy) torsion angle is 90.98 (15)°. In the crystal, mol-ecules are linked by O-H⋯O and N-H⋯O hydrogen bonds, resulting in (100) chains incorporating centrosymmetric R(2) (2)(14) and R(2) (2)(10) loops. Weak aromatic π-π stacking is also observed [centroid-centroid separations = 3.963 (2) and 3.932 (2) Å].
A nanohybrid of gold nanoparticles, polypyrrole, and reduced graphene oxide sheets (named as Au-PPy-rGO) was achieved by electrochemical deposition of reduced graphene oxide with pyrrole and the introduction of gold nanoparticles. Acetylcholinesterase (AChE) was further encapsulated in a silica matrix and immobilized on the Au-PPy-rGO nanocomposite by co-deposition with (NH4)2SiF6. The presence of PPy helped to avoid the aggregation of rGO caused by van der Waals interactions between individual sheets and significantly increased the surface area of the modified electrode. The obtained Au-PPy-rGO nanocomposite not only showed excellent conductivity but also exhibited a high electrocatalytic activity and specific affinity for thiocholine, the hydrolysis product of the enzyme, and thus an improved detection sensitivity. Since AChE molecules were protected by the circumambient silica matrix, which provided a biocompatible environment and facilitated mass transport, the fabricated AChE biosensor displayed high stability and excellent activity together with a fast response to organophosphorus pesticides. Under optimum conditions, the biosensor led to the rapid and sensitive detection of paraoxon-ethyl from 1.0 nM to 5 μM with a detection limit of 0.5 nM.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Purpose The purpose of this paper is to evaluate the photochromic performance of photochromic compounds in polymer matrices. Design/methodology/approach The poly(methyl methacrylate) PMMA and epoxy resin doped with photochromic spirooxazine (SO) are prepared and the effects of ultraviolet (UV) irradiation are studied using spectrophotometer. The reversible reaction is effected using white light. Photochemical fatigue resistance of these films is also studied. Findings Irradiation of colourless 7′,8′‐dichloro‐1,3,3‐trimethylspiro[indoline‐2,3′‐[3H]benzo[b][1,4]oxazine] (SO) doped in PMMA and epoxy resin with UV light (366 nm) results in the formation of an intense purple‐red coloured zwitterionic photomerocyanine (PMC). The reverse reaction is photochemically induced by irradiation with white light. Photocolouration and photobleaching reactions follow a first‐order rate equation. It is found that photocoloration rate constant of (SO) in both matrices is almost the same, which is unexpected. On the other hand, the rate of photobleaching reaction of (PMC) in PMMA is twice slower than that in the epoxy resin. It seems that the presence of the two chlorine atoms at positions 7′ and 8′ of the benzooxazine moiety destabilise the PMC in epoxy resin film and results in speeding up the fading process compared to that in PMMA. SO doped in epoxy resin shows much better fatigue resistance than that doped in PMMA. Research limitations/implications The PMMA and epoxy resin polymers doped photochromic spirobenzooxazine described in this paper were prepared and studied. The principle of study established can be applied to any type of polymer or to any type of photochromic compounds. Practical implications The photochromic materials developed can be used for different applications, such as coatings and holography. Originality/value The method developed may be used to enhance the performance of photochromic materials.
This book Advances in Colloid Science covers a number of up-to-date research advancement and progresses on colloids. It is a promising novel research field that has acknowledged a lot of interest recently. Here, the exciting scientific reports on cutting edge of science and technology associated to facile and economical synthesis, self-assembly, wettability, liquid crystallinity, physical properties, adoptions, morphology, control, drug design, structural properties, and prospective biological and optical implementation of newly designed colloids are concluded. This book presents an overview of recent and current colloidal study of fundamental and significant applications and implementation research worldwide. The colloidal science offers significant new and exciting challenges in biomedical, chemical, physical, and technological field. It is an important booklet for research organizations, governmental research centers, academic libraries, and R&D affianced in recent research and advancement of colloids.
The asymmetric unit of the title compound, C(17)H(19)NOS, contains two independent mol-ecules which differ in the dihedral angles between the five- and six-membered rings [12.52 (10) and 4.63 (11)°]. Weak inter-molecular C-H⋯O hydrogen bonds link the two independent mol-ecules into pseudocentrosymmetric dimers. In one mol-ecule, the O atom of the carbonyl group is disordered over two positions in a 0.699 (4):0.301 (4) ratio.
The development of high-efficiency non-noble-metal hydrogen evolution reaction (HER) electrocatalysts operating at all pH values is highly desired but still remains a challenge. In this letter, we report on developing tungsten phosphide submicroparticles as a high-efficiency HER catalyst with high durability for electrochemical hydrogen generation in acidic water. This catalyst shows a low onset overpotential of 54 mV, a Tafel slope of 57 mV/dec, an exchange current density of 0.017 mA/cm2, and nearly 100% Faradaic efficiency. It needs overpotentials of 115 and 161 mV to afford current densities of 2 and 10 mA/cm2, respectively. Moreover, this catalyst is also good in activity and durability under neutral and basic conditions.
Abstract Review: 27 refs.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.