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Production of Short Chain Aliphatic Hydrocarbon Fuel Gases – A new Renewable Energy Sources from Chrome Tanned Leather Wastes by Pyrolysis
No full textThis paper focuses on production of short chain aliphatic hydrocarbon gases (CxHy) from proteinaceous
chrome tanned leather solid waste (CLW) under pyrolysis process. The main objective of the present study was to
develop a methodology for disposal of CLW without converting trivalent chromium (Cr3+) into hexavalent
chromium (Cr6+). For this purpose the CLW was pyrolysed up to 800 °C in the batch type gasification reactor
system. The composition of the yield obtained from CLW under pyrolysis process was renewable energy fuel gases,
33.03% out of which, maximum 6.20% short chain aliphatic hydrocarbon fuel gases generated at 700 °C;
condensate liquid (CL), 33.32%; and residual ash, 33.65%. Gas samples were collected to determine the presence
of short chain aliphatic hydrocarbon gases consisting of methane, ethane, propane, butane and pentane (C1 to C5)
at 400 °C and at every 100 °C rise up to 800 °C. Gas chromatography-mass spectrometry (GC-MS) confirms the
presence of (CxHy) in the fuel gases and the green energy renewable fuel gases comprising of CxHy and H2 of about
16% could be generated from CLW. The X-ray photoelectron spectroscopy (XPS) analysis confirmed the solid
residual ash contained no carcinogenic hexavalent chromium (Cr6+)
Biofunctionalized rebar graphene (f-RG) for label-free detection of cardiac marker troponin I
No full textOne-step microwave-assisted unscrolling of carbon nanotubes to form functionalized rebar graphene (f-RG) is reported. The well-characterized f-RG on an interdigitated electrode biochip in a FET configuration showed enhanced electronic properties, as demonstrated with I-V characteristics. The developed device was biofunctionalized with specific anti-cTnI antibodies exhibiting a shift of threshold voltage from -2.15 V to -0.5 V and decrease in electron mobility from 3.609 × 10(4) to 8.877 × 10(3) cm(2) V(-1) s(-1). The new sensing strategy holds great promise for its applicability in diagnostics exhibiting high sensitivity (∼ 1 pg/mL) and specificity toward cardiac marker (cTnI)
Complementary feature sets for optimal face recognition
No full textIn face recognition tasks, one kind of feature set is not adequate to generate superior results; thus, selection and combination of complementary features are crucial steps. In this paper, the fusion of two useful descriptors, i.e., the Zernike moments (ZMs) and the local binary pattern (LBP)/local ternary pattern (LTP), has been proposed. The ZM descriptor consists of good global image representation capabilities besides being invariant to image rotation and noise, while the LBP/LTP descriptors capture the innate details within some local parts of face image and are insensitive to illumination variations. The fusion of these two is observed to incorporate the traits of both of these individual descriptors. Subsequently, in this work, the performance of diverse feature sets of ZMs (i.e., magnitude features, magnitude plus phase features, and the real plus imaginary component features) combined with the LBP/LTP descriptor is analyzed on FERET, Yale, and ORL face databases. The recognition results achieved by the proposed method are approximately 10 to 30% higher than those obtained with these descriptors separately. Recognition rates of the proposed method are also found to be significantly better (i.e., by 8 to 24%) in case of single example image per person in the training
Multiple laser-based high-speed digital shadowgraphy system for small caliber projectile-target interaction studies
No full textHigh-speed optical shadowgraphy plays an important role in study of various phenomena including projectile-target interaction for small caliber projectile. Present work reports design, development, and implementation of a multiple laser-based high-speed digital shadowgraphy system to study the behavior of a small caliber projectile in flight as well as the projectile-target interaction. System is based on Cranz–Schardin technique. Low power digitally modulated laser diodes along with low-resolution CMOS cameras in global shuttering mode are used to record good quality digital shadowgraphs. The system can record 11 shadowgraphs at a maximum frame rate of 1 million/s and is able to capture even minute details of fragments in the form of shockwaves. Operation of the system, image recording and analysis are fully computer controlled. The design and system description inclusive ultra-short pulse generator and opto-electronic triggering unit are presented and experimental results are discussed
Structural, thermal, zeta potential and electrical properties of disaccharide reduced silver nanoparticles
No full textSilver nanoparticles (AgNPs) have been synthesized using maltose as reducing agent and microwave heating as reaction initiator. The nanoparticles are studied for their optical, structural, thermal, zeta potential and electrical properties. The synthesis protocol used is fast and resulted in the formation of multi-shaped AgNPs as indicated by their optical response and TEM. The crystallite size of nanoparticles and strain of the sample was found to be around 39 nm, and 2.3 × 10−1, respectively, as calculated from XRD data. Zeta potential and electrical response both showed almost threefold increase for multi-shaped as compared to isotropic nanoparticles
Effect of Graphene in Enhancing the Photo Catalytic Activity of Zirconium Oxide
No full textGraphene, have two-dimensional structure with high conductivity, extremely high specific surface area and superior electron mobility etc. It has been regarded as an important synthesis material for various composite materials used in many applications. Especially, graphene-based semiconductor photo catalysts have attracted extensive attention because of their usefulness in environmental applications such as air cleanup, water disinfection, hazardous waste remediation, and water purification. The present study involves the photo catalytic degradation of methyl orange by photo catalytic process using different concentrations of ZrO2/graphene synthesized at different annealing temperature. A series of zirconium oxide (ZrO2, zirconia) and graphene (Gr) composites with different contents of Gr (5.7, 7.3, 8.3 %) in the composite were synthesized using zirconium oxychloride (ZrOCl2·8H2O) and graphene oxide as the starting materials. The photocatalytic activities of the synthesized composites were measured for the degradation of methyl orange dye with UV spectroscopy. The rate of decolorization was recorded with respect to the change in intensity of absorption peaks for methyl orange. The absorption peaks, diminished and finally disappeared during reaction, indicating that the dye had been degraded. The photocatalytic activity is strongly affected by the concentration of graphene in the ZrO2. The synthesized ZrO2/graphene photocatalysts are characterized by X-ray diffraction, TGA, Raman spectroscopy and UV–Visible spectroscopy. Finally, it has been concluded that graphene when employed as catalytic support for ZrO2 boost its photo catalytic efficiency
Civil Structural Health Monitoring Using FBG Sensors: Trends and Challenges
No full textStructural Health Monitoring (SHM) is a promising and challenging field of research of the 21st century. Civil structures are the most precious economic assets of any country, proper monitoring of these are necessary to prevent any hazardous situation and ensuring safety. FiberBragg Grating (FBG) sensors have emerged as a reliable, in situ, nondestructive device for monitoring, diagnostics and control in civil structures. FBG sensors offer several key advantages over other technologies in the structural sensing field. In this article, recent research and development activities in SHM using FBG sensors have been presented. Some ofthe strain-temperature discrimination techniques recently proposed by ushave also been discussed. Distributed strain sensing in a concrete bridge(field trial) using FBG sensors has been presented
Design and recording of holographic diffuser for controlled angular distribution of light
No full textNow-a-days diffusers play a pivotal role in many applications. It is desirable in many applications
that angular distribution of scattered light must be controlled in a particular manner. Present paper reports on
design and recording of holographic diffusers for controlling the angular distribution of the scattered beam.
Experimental results from recorded holographic diffuser have been compared with the conventional diffuser
Sensitive chemosensing of nitro group containing organophosphate pesticides with MOF-5
No full textA luminescent metal–organic framework, MOF-5 [Zn4O (BDC)3 (BDC = 1,4-benzenedicarboxylate)] has been synthesized by the reaction of zinc nitrate and terephthalic acid in diethylformamide (DEF) medium. The obtained fluorescent porous material has been characterized by X-ray diffraction, transmission electron microscopy, confocal microscopy, UV–vis spectroscopy, photoluminescence spectroscopy and surface area analysis. The synthesized MOF exhibits reasonably good fluorescence characteristics (excitation wavelength = 330 nm, emission wavelength = 493 nm). The potential of above Zn based MOF for the sensing of nitro group containing organophosphate pesticides (OPs), namely parathion, methyl parathion, paraoxon and fenitrothion, is demonstrated. It has been possible to detect the above four OPs separately in the concentration range of 5–600 ppb. The detection limit of the proposed method for all the said OPs is 5 ppb. Interestingly, their mixture also shows the above characteristic data. The proposed method for the sensing of nitro OPs is selective towards other OPs e.g., malathion, dichlorvos and monocrotophos
Facile Synthesis and Characterization of ZIF-8 Nanocrystals
No full textZeolitic Imidazolate frameworks (ZIFs) are important subclass of porous metal-organic frameworks (MOFs). The ZIFs structure has zeolitic framework topologies wherein all tetrahedral atoms are transition metal ions and are bridged by imidazolate (IM) units. Zeolitic imidazolate framework-8 (ZIF-8) is a prototypical member of ZIF family, constituted from zinc metal ions and 2-methylimidazole as bridging linkers. ZIF-8 nanocrystals have gained significant research interest in recent past due to its applications in various fields such as gas sensing, gas separation, catalysis and moreover it allows easy fabrication of advanced sensors. Traditionally, syntheses of ZIF-8 nanocrystals have been a challenge and were mostly done in organic solvents which are undesirable due to their environmental and health associated risk. We report here synthesis of (ZIF-8) nanocrystals through simple aqueous route method at room temperature. The synthesis method utilized simple inorganic precursors as starting material and completed within few minutes as against several hours reported in organic solvents. The obtained ZIF-8 nanocrystals were characterized by different characterization techniques like X-ray diffraction, Fourier Transformed Infrared Spectroscopy, Dynamic Light Scattering, Energy Dispersive X-ray Spectroscopy, Differential Scanning Calorimetry and Thermo-gravimetric Analysis. The synthesis method yielded a homogeneous population of pure phase ZIF-8 nanocrystals with high thermal stability with an average size of around 100nm