Ultrathin two-dimensional WSe2 has attracted huge attention due to its potential applications in future wearable electronics. Here, we demonstrate the flexible and high-performance photodetector using high-yield sonochemical exfoliation technique. An efficient and low cost fabrication strategy using Whatman filter paper is adopted for the first time for fabrication of a photodetector based on WSe2 nanodots (NDs). The WSe2 NDs have hexagonal lattice structure with P63/mmc and have indirect band gap of 1.63 eV. The exfoliation and number of layers in WSe2 NDs is confirmed by Raman, absorption, and photoluminescence spectroscopy. Subsequently, the photodetector based on WSe2 NDs is fabricated. The device shows excellent photoresponse with response time of 0.68 s and photoresponsivity of 17.78 mAW–1 and detectivity of 5.86 × 1010 Jones for 5 V. The device is analyzed for bias of 0 to 100 V and responsivity is enhanced up to 796.18 mA W–1 at 100 V bias. Furthermore, the paper-based detector exhibited great flexibility and air stability. The performance of the photodetector was also recorded in the spectral range 390 to 880 nm. Over all, the performance paper-based device advocates a novel pathway for flexible and intelligent electronics.

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A novel bacterial strain capable of decolorizing textile dyes was isolated from dye contaminated soil obtained from industrial estate of Ahmedabad, Gujarat, India. The bacterial isolate Pseudomonas aeruginosa NBAR12 was capable of decolorizing 12 different dyes tested with decolorization efficiency varying in the range of 80 to 95%. Maximum extent as well as rate of Reactive Blue 172 (RB 172) decolorization was observed when glucose (2 g x l(-1)) and yeast extract (2.5 g x l(-1)) were supplemented in the medium. The optimum dye pH and temperature for dye decolorization was found to be 7 and 40 degrees C, respectively. The decolorizing activity was found to increase with increasing the dye concentration from 50 to 400 mg x l(-1). The dye decolorization was strongly inhibited at 500 mg dye l(-1) in the medium. High performance thin layer chromatography analysis indicated that dye decolorization occurred due to the breakdown of dye molecules into colorless end products.

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SYNOPSISThe thermal degradation of virgin and HC1-treated PVC in powder form, as well as of PVC films of different thicknesses, has been studied as a function of time and temperature. The rate of dehydrochlorination was determined conductimetrically and from the polyene sequence distributions as obtained by UV spectroscopy. Increases in the rate of dehydrochlorination, ranging between 30 and 45%, were observed at all temperatures for the samples pretreated with HCl, while the corresponding activation energies were found to be lower by about 20%. For the PVC films, the rate increased with thickness, i.e., with longer residence time of evolved HCl within the sample. The results offer insight regarding the autocatalytic role of evolved HC1.

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The optical, electrical and optoelectronic properties of tin selenide crystals are of immense significance for application in photodetectors and energy conversion and storage devices. The transition metal chalcogenides possess a layered structure that interacts with each other through van der Waal forces and can also offer sites for intercalation. The low molecular weight materials like GeSe and SnSe are found in an orthorhombic structure. In this article, the optical, electrical and optoelectronic properties of as-grown tin selenide crystals are investigated. The chemical composition of the crystals grown with the aid of direct vapour transport (DVT) technique is confirmed through energy Dispersive analysis of X-rays (EDAX), at the same time the morphological analysis is accomplished using optical microscopy and Scanning Electron Microscopy (SEM). The grown crystals are characterized by powder X-ray diffraction (XRD) method to assess the structural properties of the material. The XRD evaluation found out the orthorhombic structure of the crystals with the space group 16 2h D (P cmn) having lattice parameters a = 11.490 Å, b = 4.440 Å and c = 4.135 Å. The crystallinity of grown samples was verified by transmission electron microscopy (TEM). The single crystalline nature of grown crystals was revealed by SAED pattern. The indirect optical band gap of 1.0065 eV, Urbach energy and steepness parameter are calculated utilising UV-VIS-NIR spectrophotometer. The optical absorption of as-grown SnSe crystals has been measured close to the fundamental absorption edge at room temperature. Both types of transitions, i.e. direct and indirect, are involved in the absorption process. Electrical transport properties like resistivity measurements (parallel and perpendicular path to the c-axis) had been carried out on these crystals within the temperature range 297-673 K. Anisotropy in resistivity measurements in both the directions, i.e. parallel and perpendicular direction to the c-axis was discovered. The p-type semiconducting nature was confirmed with the aid of Hall-effect measurements. For the photodetection properties of SnSe crystals, light source (670 nm) having an intensity of 3 mW/cm 2 at distinctive biasing voltages is used. The outstanding detection properties are revealed from the responsivity, specific detectivity and external quantum efficiency (EQE) of pure SnSe crystals.

Several Pluronic-based formulations were studied in-vitro and in a rat model with respect to the release and bioavailability of megestrol acetate (MA) after oral administration. It was demonstrated that an aqueous, micellar formulation comprising a mixture of a hydrophobic (L61) and a hydrophilic (F127) Pluronic copolymer, significantly enhanced the bioavailability of MA administered orally at relatively low doses (1-7 mg kg(-1)). Pluronic-based microgels (spherical gel particles of sub-millimetre size) were introduced as MA vehicles. The microgels comprised a cross-linked network of poly(acrylic acid) onto which the Pluronic chains were covalently attached. Microgels of Pluronic L92 and poly(acrylic acid) fabricated into tablet dosage forms exhibited dramatically lowered MA initial burst release. The MA release was pH-dependent owing to the pH sensitivity of the microgel swelling, with the drug retained by the microgel at pH 1.8 and released slowly at pH 6.8. In the rat model, a significant increase in MA bioavailability was observed when the microgel-formulated MA was administered orally at a high dose of 10 mg kg(-1), owing to the enhanced retention of the microgel. The study of the microgel passage through the gastrointestinal tract demonstrated the microgel retention characteristic of a very high molecular weight polymer and the absence of any systemic absorption of the polymer.