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This talk is related to chemical application of carbon nanotubes (CNT). The talk describes DC influence on a few CNT coatings, therefore research also involves investigation of electric field influence on different CNT solutions, in particular, solutions based on functionalized CNT. As a side effect of AC current influence on CNT solution nanostructurized composite was obtained. These results can be used in chemical industry, for example, in chemistry of polymers. [ABSTRACT FROM AUTHOR]

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]

This article describes the manufacturing technology of microfluidic systems on the surface of glass plates. The process of creating a gas chromatographic column using the proposed technique is considered. In accordance with the proposed technology, liquid etching carries out the formation of channels on the plate, and the sealing occurs due to the formation of siloxane bonds. In addition, the process of modifying the internal surface of the channels is described. It consists in passing saturated vapor of trimethylchlorosilane and then passing nitrogen through a sealed channel. In addition, findings of investigation of made prototypes of microfluidic systems in structure of gas chromatograph and its comparison with traditionally used gas chromatography columns are demonstrated. [ABSTRACT FROM AUTHOR]

Bacterial nanocellulose is a natural product with high potential for biomedical application. As a novel wound dressing material it needs appropriate modification for reception of antibacterial activity. In the present study 6–O– methylsulfonylaminoacetate and 6–O–toluylsulfonylaminoacetate of bacterial nanocellulose were prepared by modification of a cellulose ester and an amino acid with methanesulfonic chloride and toluenesulfonyl chloride. The resulting modified bacterial nanocellulose possess high antibiotic activity against Escherichia coli and Staphylococcus aureus and can be used in medicine as a long-acting wound dressing. [ABSTRACT FROM AUTHOR]

In this paper gives the design and simulation of high voltage power supply (HVPS) using flyback converter for electro- spinning application is discussed. Electro-spinner required an adjustable HVPS (1-50 KV) to synthesize nanofibers. Circuit of adjustable HVPS has been designed and simulated in Circuit Wizard toolbox. Various parameters such as duty ratio, frequency and input voltage have been studied. Simulation results will be useful in constructing an adjustable HVPS for electro-spinning application. [ABSTRACT FROM AUTHOR]

In this paper, dynamic strain sensing of cantilevered beam is measured by CNT based strain sensor. MATLAB simulations are performed to compare the performance of CNT strain sensor with conventional strain sensors. It has been observed that for lower strain levels performance of CNT strain sensor is far superior to strain gauge. Experimental set up consists of cantilevered beam on which CNT strain sensor–strain gauge pair is fixed near its root in a collocated fashion. An arrangement is made to displace the beam by 1mm, 2 mm and 3 mm. In comparison to strain gauge, change in resistance of CNT sensor is predominant. The superior performance of CNT strain sensor compared to conventional strain sensors are demonstrated. [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]

The present work reports the optical properties of Cr2O3 nanoparticles by using the sol-gel method and evaluation of its antibacterial activity. The morphological and structural analyses of Cr2O3 have been carried out by X-ray diffraction (XRD) methods and scanning electron microscopy (SEM). Photoluminescence (PL) spectroscopy tool was used for investigating the defects present in Cr2O3 nanopowder. To investigate the antibacterial effectiveness of Cr2O3 nanoparticles, they were applied to a medium containing Escherichia coli (E. coli) by using Kirby Bauer disc diffusion method. Nanosized Cr2O3 particles showed significant antibacterial effects on the growth of E. coli and this effect varied with the concentration of Cr2O3. Thus, Cr2O3 nanoparticles prepared through sol-gel method, due to simple manufacturing and effective antibacterial properties may find broad applications in various industries to address safety issues. [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]

In order to produce clean and low cost electricity from solar energy, it is important to establish a cost effective solution processable and scalable technique compatible with high throughput Roll-to-Roll processes. This report focuses on the optimization of ultrasonic spray deposition of the active layer for the fabrication of scalable efficient organic bulk heterojunction devices. The ultrasonic nozzle enables us to atomize the solution with picoliter drop size which gives uniform coverage and smooth film over a large area. The various parameters of the process formation were systematically investigated and optimized to get a pin-hole free, smooth and uniform film with low resistivity. Rational device optimization were carried out by one to one performance comparison between the devices fabricated by ultrasonic spray techniques and standard spin coating technique. The comparable results establishes the practical feasibility of our approach for large scale industrial applications. [ABSTRACT FROM AUTHOR]

Single walled carbon nanotubes (SWNTs) films are prepared by dispersing SWNTs in DMF solution which is filtered over flexible polycarbonate membrane by vacuum filtration method. SWNTs film has been functionalized with different amounts (0.1 mg, 0.2 mg and 1 mg) of SnO2 nanoparticles of size 20-30 nm. Sensor is made by mounting a piece of CNT and different CNT/SnO2 films on PCB headers and contacts are taken by using Au wire. The sensing behavior of CNT/SnO2 towards NO2 and NH3 in the concentration range of 0.5 to 100 ppm has been studied. The sensing response has been compared to that obtained from pristine SWNTs. SWNTs with 0.1 mg of SnO2 has given the maximum improvement of 1.6-8.5% and 0.8-1.75 times in response for NH3 and NO2 respectively, as compared to pristine CNTs.. [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]

In this paper, we have studied electrochemical performance of rod shaped ZnO nanostructure (NS) for supercapacitor application. We have performed the electrochemical performance by using cyclic voltammetry (CV) and chrono charge-discharge galvanostatic with three electrode systems. Herein we have synthesized the ZnO NS by using leaf extract of Tabernaemontana divericata as capping/stabilizing agent at 40°C. The morphology of synthesized ZnO NS has been determined by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) and powder x-ray diffraction (PXRD) have been used for elemental composition. The band gap has been calculated 3.01eV with talc plot by using data of UV-Visible spectrum. The specific capacitance of the drop casted ZnO supercapacitor on glassy carbon electrode (GCE) has been investigated by using CV curves at the voltage scan rates 20 mV/s, 40 mV/s, 60 mV/s, 80 mV/s and 100 mV/s. The obtained values of specific capacitance are 535.7142 F g−1, 401.7857 F g−1, 304.7619 F g-1, 229.9107 F g-1 and 189.2857 F g-1 respectively. The values of energy density and power density have also been calculated. The obtained values at the abovementioned scan rates are 36.4583Wh/kg and 65.6249W/kg, 27.3438 Wh/kg and 49.218820 W/kg, 20.7407 Wh/kg 37.3332 W/kg, 15.6470, Wh/kg and 28.1646 W/kg, 12.8819 Wh/kg and 23.1874 W/kg respectively. [ABSTRACT FROM AUTHOR]

The electrochemical grinding (ECG) process is a new noble hybrid machining process comprising electrochemical machining (ECM) and conventional grinding process. ECG process is more significant for machining of composite materials, super alloys and carbides. Even these materials are immensely required in the field of the modern industries and automobile industries for making of precise components with high surface quality. Developed ECG process plays viable improvement in productivity and surface finish with less wheel wear rate as compared to the mechanical grinding. In this article, the role of ECG for machining of aforesaid materials has been summarized and concentrated on the future research possibilities in the same area. It has also been discussed on mechanism, process, performance parameters and new evolution related to the ECG. Moreover, this review article becomes advantageous for researchers to understand the phenomena and new movement of research perceptive and prospective of research development in ECG process. [ABSTRACT FROM AUTHOR]

In this work, Graphitic carbon nitride (g-C3N4) was prepared from thermal condensation method using melamine as a precursor at different condensation temperatures. The characterization and detailed analysis confirmed that the molecular and surface structure of g-C3N4 depends on the synthesis condition such as temperature and atmosphere. The as- prepared samples were further characterized by field emission scanning electron microscope (FESEM), X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) for morphological, structural and molecular studies. Photocatalytic treatment was performed on Methylene Blue (MB) dye by using prepared samples as photocatalyst. Further, a comparative photocatalytic analysis was studied for all the prepared samples at different temperatures. [ABSTRACT FROM AUTHOR]

In present article, we are going to analyze the results of experimental researches of photosensitive structure properties of porous silicon (PS). The each structure have the layers of porous silicon, generated on the surface of single crystal silicon plates, and DyF3 or ZnS cover on it. The conducted researches demonstrate that the similar structure possesses high photo-electric characteristic and can be used in solar cells. [ABSTRACT FROM AUTHOR]

This paper reports and compares NH3 gas sensor response of the HNO3 functionalized SWCNTs (f-SWCNTs) and pristine-SWCNTs (p-SWCNTs). The role of (pristine and functionalized) SWCNTs for detecting NH3 gas is evaluated in terms of the sensors response, response time and sensor recovery. The results show that SWCNTs are successfully functionalized using 3M nitric acid which is confirmed through FTIR analysis. The as-synthesized samples are characterized using techniques like FESEM and Raman Spectroscopy. The study has been performed on the exposure of NH3 (8 ppm) at room temperature (40°C). The observed sensor response of p-SWCNTs and f-SWCNT sensors were 2.9% and 5.8% respectively. f-SWCNTs sensor reports an enhanced sensor response with fast response time (3 mins.), however its recovery remained slow (7 mins.) as compared to p- SWCNTs sensor respectively. The reason may be attributed to the interaction of NH3 with p-SWCNTs surface which is predominantly physisorption, whereas in f- SWCNTs it is mainly governed by the complex chemisorption process. The obtained results are in good agreement with previous reported work with enhanced NH3 gas sensor response characteristics. [ABSTRACT FROM AUTHOR]

CdS and ZnS are important chalcogenides belonging to II-VI binary compound semiconductor which has wide applications in various optoelectronic devices, medical diagnosis and drug delivery system. The present work reports the synthesis of undoped and Cu doped CdS and ZnS nanoparticles by microwave assisted solvothermal method using the aqueous molar solution of cadmium acetate, zinc acetate, copper chloride and sodium sulphide. The structural properties of the as synthesized nanoparticles have been investigated via X-ray diffraction. The XRD spectrum confirms the crystallinity of the synthesized samples. The average crystal size of the nanoparticles was estimated via Scherrer equation and was found to be around 5.64 nm and 5.46 nm for undoped CdS and ZnS respectively and the value gets reduced on doping CdS and ZnS with Cu. The optical properties of the prepared nanoparticles were examined via PL and UV Visible spectra. The optical energy band gap of as synthesized nanoparticles was estimated using UV- Visible spectra via Tauc equation, which was found to be 3.80 eV and 3.70 eV for undoped CdS and ZnS respectively. The report shows the increment of the energy band gap of CdS and ZnS after doping it with Cu. [ABSTRACT FROM AUTHOR]

Plasmonic fiber optic sensors have emerged as immensely valuable and versatile optical tools in sensor technology in contemporary scientific and engineering disciplines. The analytical performance of a fiber optic SPR sensor is, in general, studied in wavelength interrogation mode. In the current study, the analytical performance analysis of a fiber optic SPR sensor in phase interrogation scheme is presented, which probes the phase difference arising between TE (s) and TM (p) polarized components of the incident light as they propagate through the fiber optic sensing structure. The sensing probe, for this purpose, involves a silver layer of 40 nm thickness over unclad fiber core followed by zinc oxide (ZnO) layer of variable thickness. The plasmonic behavior of the proposed sensor as well as its phase response are explored with respect to analyte refractive index making use of transfer matrix theory developed for N–layered hierarchical optical media. The maximum value of phase sensitivity achieved for the proposed sensor is 2.828×105 deg/RIU for ZnO thickness of 2 nm and at an analyte refractive index of 1.3711, which is observed to decrease with an increase in ZnO thickness. [ABSTRACT FROM AUTHOR]

The emergence of 2D materials has gained immense attention for photocatalytic applications due to their thickness dependent physical and chemical properties. In this paper, MoS2 nanosheets were synthesized by low cost hydrothermal method. The sample was well characterized by X-ray diffraction (XRD) and UV-Vis spectroscopy and scanning electron microscopy (SEM) micrographs confirm the formation of MoS2 ultra-thin nanosheets. A deep and extensive photocatalytic comparative study is performed on bulk MoS2 with hydrothermally synthesized MoS2 nanosheets under the sunlight by the degradation of methylene blue (MB) dye. [ABSTRACT FROM AUTHOR]

The analytical solution of vibration on Single wall Carbon nanotubes (SWNTs) embedded in viscous material with linear and nonlinear damping subjected to parametric excitation has been investigated. The analytical non resonant solution of amplitude of nonlinear vibration is deduced using Krylov Bogoliubov and Mitropolsky method. The solution is determined till second order of approximation. [ABSTRACT FROM AUTHOR]

Present study reports the temperature sensing performance of Molybdenum Diselenide (MoSe2) based thermistor. MoSe2 has been hydrothermally synthesized and the thermistor is fabricated by drop cast method. Powder X-ray diffraction (XRD), Raman and scanning electron microscope (SEM) analysis have been used for characterizations of the prepared material. The temperature dependent sensor response shows good stability in the temperature range of 173–373K. Temperature coefficient of resistance (TCR) of the thermistor is found to be∼-0.51%/K in the temperature range of 273– 373K and it enhances to∼-1.75%/K in low temperature range (273–173K). The response and recovery time are found to be 88s and 94s in the temperature range of 273-373K respectively. This study gives a direction for the development of simple, economical and reproducible thermistor from MoSe2. [ABSTRACT FROM AUTHOR]

In the present investigation porous anodic alumina were grown electrochemically and exploited for low level moisture sensing applications. Anodization in sulphuric acid at 5V was done in a two electrode cell, to form pores of extremely small dimension. The foremost important parameter that decides the formation of entire nanostructure is the anodic voltage. Structural engineering of the samples along the channel length can be obtained by rational selection of anodic polarization, electrolyte and time. The formed nanostructures were analyzed using field emission scanning electron microscopy. A parallel plate capacitive humidity sensor with average pore diameter 6 nm was developed for moisture detection. The obtained sensitivity was 650 pF/RH%. The fabricated sensor is highly stable with negligible baseline drift and highly selective for humidity. [ABSTRACT FROM AUTHOR]

In this article we have demonstrated electrodeposition of CdS into AAO template, resulting into growth of CdS nanobelts than usual nanorods. During FE-SEM scanning something peculiar was observed; the nanobelts were whirling under the influence of focused electron beam, the reason for which is further discussed. Further, enhanced optical properties of the nanobelts were evaluated using UV-visible absorption spectroscopy and photoluminescence emission. The energy storage properties of the nanobelts were recorded using cyclic voltammetry (CV) and galvanic charging-discharging cycle (GCD) resulting into 578 F g−1 at 5 mV s−1. [ABSTRACT FROM AUTHOR]

This work presents the fabrication of a resistive biosensor to detect chronic myeloid leukemia by targeting leukemia biomarker that is P-glycoprotein attached to surface of the cell. The sensor was fabricated using multi-wall carbon nanotubes due to its high surface area, and optimized parameters such as silane binding time and antibody content were done for its efficient operation. The electrode was characterized using SEM, Raman and FTIR studies. Further, sensing was done using leukemia K562 cell line in a linear concentration range of 2x106 cells/mL – 2x103 cells/mL. The calibration plot (change in resistance v/s log concentration of K562 cells) demonstrated linearity having the regression coefficient of 0.8518 and lower detection threshold was found to be 11 cells/mL. The observed sensitivity is close to the reports available in literature where additional rigorous steps are required for fabrication. The sensing phenomenon can be simulated with Fermi level fluctuation when cell binds/ detaches on/ from the electrode surface. The sensor was found to be sensitive, cost effective, less reagents requirement and quick than the popular technologies used in hospitals. [ABSTRACT FROM AUTHOR]

Humidity sensing at low RH level (below 30%) is challenging. Since sensing is a surface activity induced phenomenon, therefore, maneuvering shape and size of surface morphology in a customized fashion is a necessity. In this report, humidity sensing characteristics of sensors with different pore morphologies were thoroughly explored. For this, three capacitive sensors with identical electrode configuration and geometry were fabricated by anodization at different anodic polarization. Sulphuric-, oxalic- and phosphoric acids were used as electrolytes to vary the pore morphology. Pores of small, medium and large dimension in nanoscale were fabricated by varying anodic polarization. Sensor response characteristics have been examined and found that both the morphology and the electrolyte composition play a decisive role in determining the capability of the sensor of its measurement level in terms of RH. The prepared sensors having various degree of sensitivity show excellent response characteristics at low RH (3%-30%) detection. Besides, the performance of the sample anodized in oxalic acid is found optimum among the three samples. [ABSTRACT FROM AUTHOR]

In this report, we present highly sensitive Vis-NIR optical detector by utilizing the extraordinary optical and electrical properties of reduce graphene oxide. Graphene oxide (GO) was produced via Hummer's technique. Uniform GO film was deposited on a quartz substrate by the spin coating technique. During the oxidation process, a large number of functional groups (epoxy, carbonyl, carboxy and hydroxyl) attached to the surface and at the edges of the GO. Due to which GO becomes electrically insulator. To regain its electrical behavior, GO was thermally reduced at 250 °C for 1 h in inert atmosphere (Argon). The microstructure of the developed film was studied before and after reduction using TEM, SEM, Raman, and XRD analyses. The fabricated sensors were thoroughly investigated for different illumination wavelengths of light (i.e., 635, 785, and 1064 nm). The photo-illumination induced sensor response as change in current was measured while the incident laser power density was maintained at 1.4 mW/mm2. As expected, there exists a linear relation between the illumination power density and photo response of the device. The maximum photoresponsivity of 1.2 mA/W was observed when illuminated with 635 nm wavelength laser at 1.4 mW/mm2 power density. The fabricated sensors show excellent reproducibility of the photoresponse at different laser wavelengths without any significant drift at room temperature. [ABSTRACT FROM AUTHOR]

ZnO nanorods were prepared at different temperatures via Vapour Solid growth method by Zinc acetate dihydrate used as a precursor. Lattice structural and surface morphology study of ZnO nanostructure have been done by characterization techniques like as XRD, FE-SEM, and optical properties by absorption and emission techniques such as Ultraviolet-Visible absorption spectroscopy and photo-luminescence spectroscopy and different phonon modes vibration, defects and bond bending by Raman Spectroscopy and FTIR spectroscopy. XRD confirmed the formation of ZnO nanostructures which were found polycrystalline in nature and having hexagonal structure. SEM revealed a rod-like shape grains and elemental composition was analysed via EDS technique and photoluminescence spectra shows decrease in luminescence with temperature which is further applicable as electron transport layer in solar cell application and appearance of weak blue green emission peak with increase of temperature indicate the well grown ZnO nanorods. [ABSTRACT FROM AUTHOR]

We have studied the electronic and magnetic behavior of monolayer black Phosphorous (MLBP) using first principle density functional theory calculations. MLBP is a semiconducting system with a dimensional dependent variable range of band gap. Creating vacancy and doping have been induced to investigate the modified stable geometry and physical behavior of the monolayer system. Pristine, vacancy induced monolayer and vacancy induced doped monolayer are considered during the calculation. Dopant concentration has been well checked via optimization algorithm to maintain the dilute magnetic semiconducting behavior of the monolayer system. Density of states and partial density of state indicates the contribution of individual orbitals in the system. Band closing nature in observed in vacancy and doped vacancy states indicating closed dense states and metallic behavior of the perturbed system. Both antiferromagnetic and ferromagnetic ordering is included in our calculation to get a charm of both ordering in the electronic and magnetic properties of the system. [ABSTRACT FROM AUTHOR]

Highly luminescent carbon dots (CDs) seem to be a good replacement for environmentally hazardous semiconductor QDs such as CdSe, CdSe/ZnS etc. CDs have been synthesized by various chemical and physical routes. However, they suffer from a drawback of variation in emission wavelength with the variation in excitation wavelength and also with dilution of CDs in the solvent. In this paper we report synthesis of highly stable CDs using citric acid and hexadecyl amine (HDA) as precursors. The fabrication conditions have been optimized and it has been observed that the concentration of HDA plays a vital role in the stability of the fabricated CDs. When the molar concentration of HDA is almost two times the molar concentration of Citric acid, good quality CDs are fabricated which are highly luminescent and stable. Stability check of these CDs is carried out by recording the emission spectra under various excitation wavelengths and concentrations of CDs. [ABSTRACT FROM AUTHOR]

In this work, nanoparticles of α-Fe2O3, α-Ho0.03Fe1.97O3 and α-Dy0.03Fe1.97O3 systems were synthesized by sol-gel method. These were characterized using powder x-ray diffraction technique (PXRD), high resolution transmission electron microscope (HRTEM) and diffuse reflectance spectroscope (DRS). The PXRD analysis reveals hexagonal crystal structure with R-3c space group, without any additional phase formation. The average particle size and distribution of grains was obtained from HRTEM micrographs. From the DRS spectra, optical band gap was calculated using Kubleka-M unk relation, which was observed to decrease by incorporating Ho3+ and Dy3+ ions into α-Fe2O3 lattice. This optical band gap decrease for the doped nanoparticles will be a way forward to realize that these nanomaterials may be promising candidates for optoelectronic devices. [ABSTRACT FROM AUTHOR]

In this article, high-quality Zinc selenide (ZnSe) and Mn-doped ZnSe Quantum Dots (QDs) synthesized by single source inorganic cluster method. X-Rays diffraction (XRD) pattern of ZnSe and Mn: ZnSe QDs have been indexed with Zinc blende (cubic) crystal structure. The Transmission electron microscope (TEM) image of doped QDs shows spherical shape of particles with an average diameter of 3.5-4.0 nm. Doping of Mn in ZnSe semiconductor host have been confirmed by photoluminescence (PL) as well as Electron paramagnetic resonance (EPR), where we have observed direct emission from Mn+2 states (4T1 → 6A1) and six hyperfine splitting in EPR signal. [ABSTRACT FROM AUTHOR]

A self-supported NiCo2O4 on Ni foam was prepared by electro-deposition method. Then the NiCo2S4 micro- spheres are derived by sulfurizing the NiCo2O4 using CVD at 300°C and explored its energy storage performance towards supercapacitor. Importantly this type of micro-sphere like geometry provides better exposure of redox active sites and more accessible surface area showing enhanced charge accumulation rate. These NiCo2S4 micro-spheres shows excellent charge storage performance in terms of very high specific capacitance value of 1111 F g−1 at current density 20 A g−1 and high energy density of 39 W h kg−1 at power density 23 kW kg−1 with a prolonged cycling stability over 5000 repeated cycles. Owing to excellent electrochemical performances, we presume that the as synthesized NiCo2S4 micro-spheres would be a permissible and efficient active electrode material for future energy storage systems. [ABSTRACT FROM AUTHOR]

The herbicide 2,4-Dichlorophenoxyacetic acid (2,4-D) affects the environment through its moderate toxicity in water bodies and caused water pollution. The aim of this study is to investigate the degraded amount of traditionally used low-cost herbicide e.g.2,4-D from the water by using kinetic parameters with the help of a cost- effective new photo-catalyst Graphene-Polyindole nanocomposites (Gr-PIn NC). This nanocomposite (NC) synthesized by using the sol-gel technique and characterized by X-ray diffraction (XRD) and Scanning electron microscope (SEM) spectroscopy, which reveals the amorphous character and dispersed form of Polyindole on Graphene layers. Furthermore, Fourier-transform infrared (FTIR)-spectra confirm the vibrations phenomenon in polyindole due to the presence of pi-pi (π-π) interactions of graphene carbon double bonds (C=C) between Graphene layers. The Gr-PIn NC rate constant results exhibited almost 99% promising photodegradation efficiency for 2,4-D herbicide in presence of UV-vis. light irradiation via production of highly reactive oxygen species and, where synthesized nanocomposite shows its efficiency as twice than the pure polyindole polymer. [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]

In the present work, YBCO superconductor and their nanocomposite with MnO (YBCO:MnO(1%)) were synthesized using solid state reaction method. The orthorhombic phase formation of YBCO superconductor and after adding of MnO in the YBCO:MnO(1%) nanocomposite confirm by X-ray diffraction (XRD) patterns, there is no change in the crystal structure of YBCO. Scanning Electron Microscopy (SEM) analysis confirms the morphology of microstructure and Energy Dispersive X-Ray (EDX) spectra confirms the elemental identification of pure YBCO superconductor and YBCO:MnO(1%) nanocomposites samples, respectively. No decrease in the critical temperature (Tc) of YBCO was observed after incorporation of MnO(1%) in YBCO. Magnetization vs. Magnetic field (M-H) measurement was also performed using PPMS. The increased value of critical current density of YBCO:MnO(1%) nanocomposite has been achieved compared to pure YBCO which has been attributed to enhanced flux pinning due to presence of Mn in YBCO matrix. [ABSTRACT FROM AUTHOR]

In this work a new structure is proposed called Bulk Multigate Junctionless Transistor (BMGJLT) with non-uniform doping profile. The simulation shows that the BMGJLT with non-uniform doping gives better results in terms of ON to OFF current ratio, subthreshold swing (SS), drain induced barrier lowering (DIBL), and threshold voltage (Vth) variation. The results also show that the BMGJLT outperform the SOI Multigate Junctionless Transistor (SMGJLT) with uniform and/or non-uniform doping in terms of short channel characteristics. The simulation is performed using Sentaurus TCAD software. The improved results of the proposed device show that it will be an attractive device for future technology node. [ABSTRACT FROM AUTHOR]

CdTe is an important II-VI binary compound material which is widely used as photovoltaic applications. In this work pure and Copper doped CdTe nanoparticles have been synthesized. The synthesis has been carried out by microwave assisted method. In this study the doping effect of Cu on the structural and optical properties of CdTe nanoparticles have been discussed. For the synthesis of nanoparticles the chemicals used were cadmium acetate, Tellurium powder, ethylene glycol, hydrazine hydrate and copper chloride. The as synthesized CdTe and Cu doped CdTe nanoparticles were found to be in crystalline phase which has been confirmed by X-ray diffraction (XRD). The average size of the nanocrystallites were calculated by using Debye- Scherrer formula and was found to be around 65 nm for pure CdTe and it reduces to 52 nm after doping of Cu in CdTe. The bandgap of the nanoparticles was calculated using UV-Visible absorption spectra. The result showed that the bandgap values were blue shifted from the bulk one. [ABSTRACT FROM AUTHOR]

This work reports the synthesis of Fe-doped piezoelectric ceramic BCZT ((Ba0.85Ca0.15)(Zr0.10Ti0.90)O3) using solid- state reaction. The effect of Fe doping on the structure of BCZT piezoceramic has been investigated by varying its doping concentration in the prepared samples. X-ray diffraction patterns and Raman spectroscopy analyses ascertain the presence of Cubic phase in the prepared ceramic material. The SEM micrographs obtained at different magnifications confirm the increasing inter-diffusivity among the particles. Additionally, the EDS data confirms the proportion of elemental built-up of these materials. [ABSTRACT FROM AUTHOR]

Synthesis of cupric oxide nanoparticles (CuO NPs) were done by modified sonoelectrochemical process which is pulse sonication using copper (II) acetate and sodium hydroxide as a precursor in the presence of glucose as a surfactant. In the present study, poly(N-vinylpyrrolidone) (PVP) was also used as the stabilizing agent in the synthesis of CuO nanoparticles. The copper (II) oxide nanoparticles were characterized by X-ray diffraction (XRD), UV-Vis, FT-IR, Scanning electron microscope (SEM) and transmission electron microscope (TEM). The PVP was found to greatly promote the dispersed and homogeneous phase of copper oxide nanoparticles. The influence of the parameters of electrochemical and ultrasonic pulses on the particle diameter was also studied. All the samples have been calcined at 500 °C and found an absorption peak in between 250-300 nm by UV-vis spectrophotometer. Furthermore, the absorption spectra of CuO nanoparticle were examined to explore the possibility of using them as a material for applications such as solar cell. The XRD and TEM analysis showed the high crystallinity and lesser size of CuO nanoparticles with PVP. XRD peaks value depend on the calcination temperature and reaction time that reveal an average crystallite size found to be 30 nm using Scherrer equation. [ABSTRACT FROM AUTHOR]

The power conversion efficiency (PCE) of conducting polymer solar cells (PSC) has been found to increase significantly by incorporating a Deoxyribonucleic acid - hexadecyltrimethylammonium chloride (DNA- CTMA) electron blocking interlayer (EBL) between the hole transport layer (HTL) and poly(3-hexylthiophene) (P3HT): [6,6]-phenyl C71 butyric acid methyl ester (PC71BM). The idea is to block the unwanted electrons reaching to PEDOT:PSS and ITO anode. The photo generated electrons from lowest unoccupied molecular orbital (LUMO) level (2.9 eV) of P3HT face high barrier height towards PEDOT: PSS due to 0.9eV LUMO level of DNA. The DNA-CTMA EBL reduces the non-geminate recombination at the HTL and P3HT: PC71BM interface resulting in significant enhancement∼33% of PCE. [ABSTRACT FROM AUTHOR]

Due to the fact that, excessive stresses induced by drastic moisture and temperature gradients make the engineering structures susceptible to failure. But only thermal effect has been considered so far to study the frequency analysis of FGM nanobeams, wherein most of the cases some rule of mixture were used to grade the mechanical properties along certain directions. It has been observed from the literature that the interfacial stresses arise which is the main cause of failure of composite structures is reduced up to an extent if the mechanical constants are varying under sigmoid law formulation. Hence, this paper reported the frequency behavior of functionally graded nanobeam under hygrothermal effect, where the mechanical constants are assumed to vary smoothly along the thickness direction using power law or sigmoid law distribution. The MUMPS Eigen solver which is exists in COMSOL Multiphysics® (version 5.2) software is employed to obtain the Eigenfrequencies and corresponding mode shapes. Hence, this study can be helpful directly or indirectly in development of highly efficient hygrothermal Nano sensors based on functionally graded materials for health monitoring purpose. [ABSTRACT FROM AUTHOR]

The 2-Dimensional Graphitic Carbon Nitride (g-C3N4) a class of polymeric semiconducting material analogous to graphite possesses unique electronic and optical properties due to its graphene like structure. It exhibits excellent chemical and thermal stability (up to 600oC in air), enabling it to function in liquid and gaseous environments as well as at high temperatures. It possesses appealing electronic structure i.e. medium, direct band gap semiconductor having band gap of 2.7 eV with conduction and valance band lying respectively at -1.1eV and 1.6 eV vs normal hydrogen electrodes which makes them potential candidate as electrode modifying interface layer for various optoelectronic devices. This work focusses on the preparation of nanostructured g-C3N4 by liquid exfoliation and chemical oxidation processes. Systematic investigations on structural and optical properties of the prepared materials reveals the formation of the nanosheets and quantum dots of g-C3N4 and enhanced charge collection capability for the nanostructures compared to the as prepared material. The prepared g-C3N4 nanostructures will be used for improving the performance of optoelectronic device especially organic solar cells. [ABSTRACT FROM AUTHOR]

Copper nanowires of 50 nm diameter have been successfully fabricated via electrodeposition using commercial polycarbonate membrane of pore diameter 50 nm and thickness 10 µm as template. The morphology of wires and crystal structure of material have been analysed by field emission scanning electron microscopy and X-ray diffraction respectively. Nanowires are found to be vertically aligned with cylindrical geometry and thoroughly uniform in diameter. X-ray diffraction pattern exhibit the face centred cubic structure of prepared nanowires. The lattice constant and crystallite size are found to be 3.605 Ȧ and 31.5 nm respectively. I-V characteristics indicate the ohmic behaviour of prepared nanowires. Electrical conductivity is estimated to be 2.02 × 107 Ω−1m−1. [ABSTRACT FROM AUTHOR]

Failure mode and effect analysis (FMEA) is a significant procedure to guarantee the long life of PV module after 20 years. An overview of the potential failures for the mono-c-Si technology is provided initially. 90 mono-crystalline silicon (mono-c-Si) photovoltaic (PV) modules mounted at the National Institute of Solar Energy (NISE), Gurgaon were considered to perform the FMEA after 24 years of outside exposure in a semi-arid climate of India. Different investigation has been approved out following visual inspection, I-V characteristic, electroluminescence (EL) characterization, insulation resistance and risk priority number (RPN) for the FMEA validation. Results show the insulation resistance and the hot spot are the most severe failure modes for the mono-c-Si PV modules under the semi-arid climate of India. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWNT's) are prepared by using a thermal catalytic-chemical vapor deposition (CVD) using acetylene gas as the precursor and powdered nickel as catalyst. Argon gas is used as a carrier gas and the growth characteristics of MWCNT's were controlled using flow rate, Ar/C2H2 ratio and temperature. The interaction of the electron beam with MWNT's is investigated using a scanning electron microscope in the regime of 5 to 30 kV. The structural details of the MWCNT's were studied using X-ray diffraction and FTIR spectroscopic analysis. Interestingly, the nanotubes have grown as helical/spiral coils with multi-terminal junctions as Y or H were observed. The FTIR analysis showed C-C, C=C, C-H bending and stretching modes at 1100, 1531, 1593, 924, 2924 cm-1 confirming the presence of multiwalled carbon nanotubes. Further, the XRD analysis showed sharp reflections of (002), (101) and (110) planes. The electron beam interaction with multiwalled carbon nanotubes showed the axial joining of tubes. The carbon atoms found to have displaced from the surface of MWCNT's create vacancies and disordered rings of carbon structures. These disordered rings of two different nanotubes joined together as they bend due to potential field. [ABSTRACT FROM AUTHOR]

Ultra thin short-chain polymer films near melt under strong confinement have been investigated, using NVT-Monte Carlo simulation method. Bottom surface of the simulation box, has affinity to monomers. The upper surface has hard wall interaction with monomers. The pattern formations in polymer films with thickness of the order of few tens of nanometers i.e. <100 nm, are generally explained on the basis of spinodal mechanism. We report spinodal like tearing mechanism of linear chain ultra-thin polymer films with intra-chain monomers connected via finite-extensible non-linear elastic (FENE) potential. Morse potential is taken for inter-chain bead-bead interactions. It is shown that the influence of Morse potential can propagated via FENE potential and vice-versa. The free end segments of the chains are observed to be more dynamic. Free end monomers show coalescence, initiating tearing of the films. So, one may scientifically speculate that the long-range van-der Waal type force no longer seems to be the lonely cause of rupturing of thin nano-films. Rather than interfacial effects and the more dynamic free end chain configurations of short chains interplay with the earlier one significantly. Formation of self-aligned quasi-equilibrium nano- structures as; strip-like and fibrous ones is reported for different thicknesses and interaction parameters of the films. Polymer chains with 30 monomers are taken with three different film thicknesses. Total 160, 200 and 240 chains are taken for three different cases of studies. The pattern formations appear to be of replicating nature. It makes this work noteworthy, especially for bio-physicists and chemists, working with macromolecules. Rupturing of film is also reported on chemically patterned substrates with variations in surface affinity to monomers in order to reveal the delicate interplay of molecular forces and interfacial effects, in case of short chain free end polymer films under strong confinement. [ABSTRACT FROM AUTHOR]

An eco-friendly and green procedure for the synthesis of silver nanoparticles (AgNPs) using the aqueous extract of leaves of phyllanthusacidus: phyllanthus family and silver nitrate as the source of metal has been proposed. The formation of silver nanoparticles (AgNPs) has been investigated by the regular increment of an acute surface plasmon resonance (SRP) band at 432 nmusing UV–Visible spectroscopy. Silver nano-particles (AgNPs) have further been characterised by Fourier Transform Infrared Spectroscopy, powder X-ray diffraction method. The shape and size of synthesized nanoparticles have further been determined by Transmission Electron Microscope (TEM). The synthesized AgNPshas been applied curiously for the selective detection of environmental hazardous Hg2+ ions in aqueous medium using naked-eye as well as UV-Vis spectral change. Moreover, the silver nanoparticles exhibit reversible response for the detection of Hg2+ ion. [ABSTRACT FROM AUTHOR]