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Performance Testing and Evaluation of On-Farm Mobile Paddy Dryer
Get PDFEfficient drying from any mobile paddy dryer would result in the superior quality of the product within a desirable time. Dryer was evaluated using 5332.5 kg of freshly harvested paddy at 21.01% moisture content (w.b). The air velocity at top layer was found to vary from 0.50 to 0.33 m/s at loading condition and 1.7 to 0.6 m/s at no-load condition. The moisture content, the coefficient of uniformity (Cu) and moisture ratio at bottom of the drying chamber were observed to vary from 21.03 to 13.44% (w.b), 91.47 to 98.32%, and 0.928 to 0.085 respectively during the start to the end of the drying. The temperature of the drying chamber at bottom and top layers were found to vary from 35.57 to 32.47°C and 40.63 to 32.47°C, respectively. The relative humidity values at the bottom and top layers were 95.87 to 94.27% and 72.40 to 93.43%, respectively during drying. At the end of drying after 4.5 h, the final moisture was estimated to be 15.23% (w.b). The thermal efficiency, heat utilization factor and effective heat efficiency were calculated to be about 58.5%, 0.99 and 0.89, respectively. The total power requirement was assumed to be 15 kW. The cost of drying was found to be Rs. 943 /h and Rs. 0.79 /kg of paddy
Management, conversion, and utilization of waste plastic as a source of sustainable energy to run automotive: a review
No full textIncreased usage of plastic and absence of an efficient system to address its non-degradability has become a serious issue threatening the human life. On the other hand, increased fossil fuel consumption which led to their depletion necessitates the search for an alternative that could replace the conventional fuels and alongside abate the emissions. Both the nondegradability of plastic and need for an alternative fuel can be addressed by converting the waste plastic to useful energy. The present article reviews about pyrolysis, a chemical treatment to convert waste plastic to energy. It also focuses on its functional feasibility as a fuel in a compression ignition engine. Reportedly, waste plastic oil when used in a diesel engine yields lesser thermal efficiency, higher brake specific fuel consumption, increased emissions of carbon monoxides, and oxides of nitrogen and unburnt hydro�carbons. Irrespective of its disadvantages, it is worthwhile to note that it is
waste plastic which is converted to useful energy. However, not much work on the technical feasibility and functional efficacy of waste plastic oil as a fuel in a diesel engine is reported, and hence, research in this application seems to gain its focus in near futur
Speed estimation of rotating machinery using generated harmonics.
No full textThe use of vibration sensors for rotational speed estimation has been found to be an effective and reliable technique. In general, the fundamental rotational frequency (f) component observed in the vibration spectrum represents the rotational speed. However, for a better accuracy of estimation, large sample duration is required which results in a higher data acquisition time, computational time and data storage. Hence, the estimation of speed accuracy with the vibration signal of a short duration is a challenging task. This paper proposes an algorithm, which requires extraction of the fundamental rotational frequency component and later, the artificial generation of its corresponding harmonic components,
for the accurate estimation of speed. The proposed algorithm can be used to estimate the speed of any rotating machiner
Application of Scanning Electron Microscopy and Fourier-Transform Infrared Spectroscopy to Study Surface Design and Chemical Group Components of Merino Wool, Paschmina and Angora Fibers
Get PDFTextile fibrous materials are used for making fashion utility products in day to day use. These fibers find applications in polymer blends,composites, fiber reinforce plastics, bio-medical textiles and many such high end uses. However, fibers like merino wool, pashmina and angora fibers are some of the natural animal fibers which are obtained in nature and find wide applications if converted into usable fashion products.These natural fibers are characterized with specific microstructure which can be tapped to design and create innovative fashion products. The importance of understanding these surface and micro-structures helps in designing and engineering a particular fashion product in textile science and engineering. In his study we look into the finer detail application of SEM used to characterize the surface, inter surface and other dynamic properties of these fibers. Scanning electron microscope has the capability to image these fiber surfaces at different magnifications which thus facilitates the observations to be examined at varying conditions of usage. These SEM images also gives insight into the steps that can be used to manipulate the process and product development steps used for textile materials. On the other hand spectral analysis using Infra-red spectroscopy gives broad information on the qualitative and quantitative analysis of these fibers. FTIR helps in elucidation and identification of chemical groups and interfer structure property relationship of these natural fibers which are obtained from animal source
A study on the compressive residual stress due to water jet cavitation peening
Get PDFThe repetitive cyclic loads on the forming tool tend to fatigue failure. Molybdenum-based high�speed steel forming tool is extensively used for producing bevel gears but, often failure occurs at the root of tooth zone. To increase the tool life, an attempt has been made to provoke beneficial compressive residual stress on the root surface of form tool by waterjet turning cavitation peening process. The cavitation peening operation is done in the forming tool by directing the high pressure waterjet of 27 MPa to the root section of the teeth region. The cavitation operation is governed by the system parameters like waterjet pressure at the nozzle exit, stand-off Distance, nozzle angle and the processing time per unit length. The residual stress induced on the sample is confirmed through X-ray diffraction technique and the effects of beneficial residual stress are measured at different operating conditions on hardness and surface profile and they are compared with the nascent sample. The study reveals that lower operating levels of Stand-off distance, nozzle angle of 45° induce more compressive residual stress around tooth region with less distortion at the surface profile. The waterjet impinged surface is observed through microscopy examinations and evaluate
An Investigation into comfort properties of polyester fabric by surface modification with polyvinyl alcohol
Get PDFIn this investigation the polyester multifilament fabric have been considered and treated with poly vinyl alcohol (PVA) in alkaline media. The fabric is treated with different concentration of PVA at different temperature and time. The effect of these factors concentration, temperature and time have been analyzed by Box-Behnken experimental design, and optimum parameters were found out. Further it is found that there is significant difference of these factors on to the comfort related properties that are air permeability and wicking. FTIR spectroscopy studies also have been carried to observe the surface modification by confirming the presence of hydrophilic group that is hydroxyl group
Design, Synthesis and Biological Evaluation of 2 (((5-aryl-1,2,4-oxadiazol-3-yl) methyl)thio)benzo[d]oxazoles: New Antiinflammatory and Antioxidant Agents
Get PDFThe oxadiazole linked benzoxazoles derivatives were designed using scaffold hopping approach and their molecular level interactions with both isoforms of cyclooxygenases, Cyclo OXygenase-1 (COX-1) and CycloOXygenase-2 (COX-2), were carried out using docking protocols. Mini library of oxadiazole linked benzoxazoles derivatives were synthesized and tested for their COX inhibitory activity by in vitro enzyme assay. The results indicated that compound 2-(((5-(2,4-dichlorophenyl)-1,2,4-oxadiazol-3-yl)methyl)thio)benzo[d]oxazole (5 h), 2-(((5-(4-
nitrophenyl)-1,2,4-oxadiazol-3-yl)methyl)thio)benzo[d]oxazole(5j) and 2-(((5-(4-(trifluoromethyl)phenyl)-1,2,4-oxadiazol-3-yl) methyl)thio)benzo[d]oxazole (5 k) selectively inhibited COX-2 enzyme. The compound 5j exhibited strong selective COX-2 inhibition (IC50=4.83 μM) followed by compound 5 h (IC50=5.10 μM) and 5 k (IC50=6.70 μM). The in vivo anti-inflammatory activity of compound 5j was found to have better efficiency than the standard drug Ibuprofen at both 3 h and 5 h intervals. The significant molecular level interactions with respect to position of benzoxazole, 1,2,4-oxadiazole and substituted aryl groups in both COX-1 and COX-2 active sites were discussed. Subsequently, 2,2-diphenyl-2-picrylhydrazyl (DPPH) anti-oxidant activity was also checked for all the compounds and the compound 5j was found to be good anti-oxidant among the series with an IC50 of 34.5 μM
Significant Enhancement of Photoactivity in One-Dimensional TiO2 Nanorods Modified by S-, N-, O-Doped Carbon Nanosheets
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Titanium dioxide (TiO2) represents one of the most active photocatalysts among metal oxides for the degradation of pollutants and for solar water splitting to produce hydrogen. The most critical drawbacks hindering its broad practical use are the absorption majorly in the UV part of solar spectrum and slow charge dynamics. Combination of TiO2 with a suitable partner in a hybrid nanostructure can effectively address these drawbacks. Here we report a novel nanocomposite system based on one-dimensional TiO2 nanorods wrapped with a sulfur-, nitrogen-, and oxygen-doped carbon (SNOC) nanosheets. The SNOC nanosheets are synthesized by a cost-effective and facile route using eco-friendly carrageenan as a sulfur, oxygen, and carbon source and urea as a nitrogen source. Silica was used as the templating agent that leads to large surface area materials after its removal at the end of the synthesis. Therefore, the synthesized material exhibits superior photocatalytic performance for decoloring representative Rhodamine B (RhB) under visible light irradiation. SNOC shows the apparent rate constant of 7.6 × 10–3 min–1, which is almost 3 times higher than that of a SNOC material without using silica (2.8 × 10–3 min–1). This performance of doped carbon material can be assigned to the effect of large surface area and effective visible light adsorption. The TiO2 NRs / SNOC nanocomposite was investigated for photoelectrochemical water splitting showing much higher photocurrent densities (0.85 mA cm–2) than pure TiO2 nanorod arrays (0.35 mA cm–2), which was due to significant improvement in the charge transfer dynamics and co-catalytic effect of SNOC. All the materials prepared were evaluated on the basis of physical properties such as crystalline structure, optical absorption, surface topography, and electronic properties.
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High capacity electrospun MgFe2O4–C composite nanofibers as an anode material for lithium ion batteries
No full textMgFe2O4 -C composite nanofibers were prepared via electrospinning technique followed by carbonization at 600 8C.
Thermogravimetric-differential thermal analysis (TG-DTA) results showed ignition, decomposition and carbonization temperatures of the as-grown fibers. Formation of the nanocrystalline phase of the MgFe2O4 over the amorphous phase of the carbon fibers sample was confirmed from the analysis of the measured XRD results. FE-SEM images of the as-spun and calcined fibers sample showed that the formation of one dimensional (1-D) MgFe2O4 -C composite nanofibers and the formed 1-D nanofibers were well interconnected with high porous structured morphology. The electrochemical properties of the MgFe2O4 -C composite nanofibers sample were tested as an anode material for lithium-ion battery. Lithium-ion battery made up of the newly developed MgFe2O4 -C composite nanofibers sample, used as an anode material, showed discharge capacity of 575 mAh g @1 at a current density of 100 mA g @1 after 20th cycles. Further, the discharge capacity of the lithium-ion battery also measured at a high current density of 1 A g @1 and it was found to be 433 mAh g @1 even after 85 cycles. Also, the lithium-ion battery showed exceptional reversible capacity with the coulombic efficiency of 99.6% even after 85 cycles at a high current density of 1 A g @1 . Hence the electrochemical properties suggest that the newly developed MgFe2O4 -C composite nanofibers can be used as high capacity anode materials for lithiumion batterie
An efcient copper-based magnetic nanocatalyst for the fxation of carbon dioxide at atmospheric pressure
Get PDFIn the last few decades, the emission of carbon dioxide (CO2) in the environment has caused havoc across the globe. One of the most promising strategies for fxation of CO2 is the cycloaddition reaction between epoxides and CO2 to produce cyclic carbonates. For the frst time, we have fabricated copper-based magnetic nanocatalyst and have applied for the CO2 fxation. The prepared catalyst was thoroughly characterized using various techniques including XRD, FT-IR, TEM, FE-SEM, XPS, VSM,
ICP-OES and elemental mapping. The reactions proceeded at atmospheric pressure, relatively lower temperature, short reaction time, solvent- less and organic halide free reaction conditions. Additionally, the ease of recovery through an external magnet, reusability of the catalyst and excellent yields of the obtained cyclic carbonates make the present protocol practical and sustainabl