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There has been increased concern during the past few decades over the last-line antibiotic resistant organisms reported from many parts of the world. Although bacterial nanocellulose (BNC), product of Komagataeibacter bacteria strains, offer unique material characteristics, it does not exhibit antibacterial activity. In present study, we produced a coating which is relative to bacterial nano-cellulose (product of Gluconacetobacter sucrofermentans B-11267) loaded with N',N'-hexane-1,6-diylbis[N-(4-chlorophenyl) (imidodicarbo-nimidic diamide)] and covered with thin silver films from 1 to 30 nm. For making thin layer of silver, magnetron sputtering (ETNA100- MT, NT-MDT) was used on BNC dried to a constant weight without heating of sample. The surface modification of the BNC was confirmed using scanning electron microscopy. Cytotoxicity tests of cellulose nanofibril-based structures on fibroblasts culture identified moderate cytotoxic effect. Significant antibacterial activity of the composite was achieved for Gram-negative as well as for Gram-positive bacteria. [ABSTRACT FROM AUTHOR]

The present study is focused on losses analysis of CdTe and micromorph PV modules installed in composite climate of India. A comprehensive module characterization with the related uncertainty analysis has been carried out by using the real electrical parameters measured at the operating field conditions. The impact of cracks in the PV module on the I-V curve has also been evaluated. A power drop of 49% has been recorded in micromorph PV modules as a result of 24% reduction in the panel area due to crack defects. The performance assessment of both the technology PV modules (CdTe and micromorph) has been initially carried out over a period of one year field exposure. Irradiance, temperature and spectral effects have been identified to quantify the corresponding losses/gain in power generation. The performance ratios of CdTe and micromorph PV modules have been found to be 80% and 65%, respectively. Spectral and temperature losses up to −29.2% and −10.1%, respectively have been recorded in the micromorph PV module. However, both PV module technologies' results are found insensitive to the irradiance effects with negligible losses of approximately -1%. Overall, the CdTe module technology is found to be more efficient than the micromorph PV modules in composite climate of India. [ABSTRACT FROM AUTHOR]

Rare-earth based manganese oxide films having optimized compositions La0.7Ca0.3MnO3(LCMO) are fabricated using R.F Sputtering technique on n-type Si/SiO2substrate at ambient temperature and 40 millibar oxygen partial pressure with subsequent post annealing at 900°C for a duration of 12 hours. The polycrystalline LCMO composite target is synthesized using conventional solid- state reaction route. Positive magneto-resistance is observed in studied hole doped manganite at room temperature. This shows that the present LCMO is paramagnetic at room temperature. X-Ray diffraction shows that sample is crystallized in single phase and SEM micrographs and EDS report depicts the surface morphology of LCMO. Resistance measurements are done using standard four probe technique at 300 K and at zero field,0.5 T and 1.5 T. Magnetoresistance (MR) comes out to be about 10.28% at 1.5 tesla, which is remarkable in itself. [ABSTRACT FROM AUTHOR]

Transition Metal Dichalcogenides (TMDs) have been fascinating a wide range of scientific interest. Molybdenum disulfide (MoS2) is the most focused TMDs. In this study, the ultrathin layer of MoS2 was synthesized through sulfurization using molybdenum oxide (MoO3) and sulfur(S) powder as precursors on SiO2 substrate in self-assembled CVD at fixed temperature. The sample was further studied using various characterizations viz. Raman Spectroscopy, Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy technique (FTIR) and Photoluminescence (PL), which showed that MoS2 can be fabricated on SiO2 substrate easily by maintaining the temperature at 775°C for 20 to 30 minutes. [ABSTRACT FROM AUTHOR]

Two dimensional (2D) metal halide perovskites are being extensively studied as they can serve as promising materials for various optoelectronic devices such as light emitting diodes (LED), lasers, photodetectors etc. The optical properties of these 2D perovskite can be tuned by varying the stoichiometric compositions of metals (Pb, Sn, Ge, Bi) and halides (Cl, Br, I). Here we report, a single step synthesis process for the fabrication of mixed halide based 2D perovskite of type (C4H9NH3)2PbI4(1-y)Br4y (y=0-1). By changing of iodine with bromine in metal halide (Pb-X) network of these mixed halide 2D perovskites, we have achieved well controlled and uniform tunability of intense room temperature exciton absorption peaks from green to UV region (513 nm to 405 nm) of spectra. Highly crystalline and layered structure of the mixed halide 2D perovskite thin films (hereafter PTF) are confirmed by using thin film X-ray diffraction (XRD) studies whereas, Energy dispersive X-ray (EDAX) analysis confirms the uniform distribution of iodine and bromine in the thin films, thus supporting that our demonstrated synthesis route is very useful and easy in producing single phase mixed halide perovskites. [ABSTRACT FROM AUTHOR]

Spray deposited poly (3,4 ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS) is used as a hole transport layer (HTL) at different thickness. These HTL layer is characterized in terms of structural and electrical properties. The thickness of HTL layer is varied from 40 to 120 nm by altering deposition time from 20 to 60 sec. The lowest thickness HTL in 20 sec deposition time is not efficient because the small droplets after atomization was dried very quickly before spreading and complete merging on the hot surface producing voids which affects the photovoltaic outcomes. The optical microscopy images revealed that an improvement in the morphology of PEDOT:PSS layer with increased film thickness from 40 to 80 nm due to better packing density. On further increasing the spray time from 40 to 60 sec HTL thickness increases to 120 nm, consequently absorbance of HTL increased which diminishes the performance of the devices. The roughness of PEDOT:PSS layer is observed minimum for 80 nm thickness HTL. The bulk heterojunction organic solar cells (OSCs) with conjugated polymers PTB7 and PC71BM on the HTL of spray coated PEDOT:PSS of is fabricated. The power conversion efficiency (PCE) observed maximum for 80 nm thick HTL due to the optimal surface morphology with least surface roughness and good transparency. [ABSTRACT FROM AUTHOR]

Solution processing of semiconductor thin film has got a lot of consideration because of lower cost production and simple fabrication techniques, which is crucial for many optoelectronic device applications. Here we use the binary solvent mixture of hydrazine and Ethylenediamine (EDA) that possess remarkable ability to dissolve almost all chalcogenide materials at solvothermal condition, for the fabrication of Selenium based thin films. The high absorption properties of such low temperature solution processed films and their intrinsic environmental stability opens up new possibilities to utilize the selenium for photovoltaics applications at an economic scale. In this paper we discuss the dissolution of Selenium in Hydrazine and EDA solvent. Dynamic Light Scattering (DLS) showed the particles size is in the range of 100nm which clarify the low surface roughness of the film. Optical absorption is discussed too. [ABSTRACT FROM AUTHOR]