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Determination of flow front velocity and optimal injection pressures for better impregnation of E-glass with polyester in resin transfer mold,
No full textFlow front velocity of resin plays a key role in yielding better impregnation of fiber reinforcement in resin transfer molding to fabricate quality composites. A video camera was used to
capture the patterns of resin flowing below the grid lines drawn on the acrylic sheet of resin transfer mold and also to accurately measure the flow front velocity using an image conversion tool. The effect of flow front velocity, permeability, Reynolds number and void content at five different injection pressures on chopped strand E-glass/polyester composites consisting of 4, 5 and 6 layers has been studied. On the basis of Reynolds number of resin flow and void content present in the composite,
optimal injection pressures are suggested for better impregnation of preform. Composites processed at these injection pressures gave superior properties in tension and flexure. Fractured parts of the specimens were examined on Scanning Electron Microscope to explain the causes of superior
mechanical propertie
Push Recovery System and Balancing of a Biped Robot on Steadily Increasing Slope of an Inclined Plane
No full textThe present research paper demonstrates the push recovery system and balancing on an inclined plane by 20 degrees of freedom (DOF) small sized biped robot. Here, the authors developed an algorithm to balance the posture of the biped robot while standing (that is, stationary mode), and balancing on an inclined plane with steadily increasing slope. To maintain
stability of the biped robot, stability controllers are integrated into the walking controller. This enables the robot to sense any disturbance, and perform necessary action to maintain its stability. For measuring the external disturbances and orientation of the ground, an inertial measurement unit sensor
is fitted inside the robot. Further, the robot is allowed to generate internal torque by the movement of its body parts to resist external disturbances. This principle is extended to test the balance of the biped robot on an inclined plane with increasing inclination angle. The robot is seen to successfully exhibit the two tasks, such as push recovery and maintaining the balance on the steadily increasing slope of a sloping surface in real-time
An assessment on removal performance of Arsenic with treated Turbinaria vulgaris as an adsorbent: characterization, optimization, isotherm and kinetics study
Get PDFIn this current research, batch experiments were performed toward the characterization and optimization of arsenic removal by Turbinaria vulgaris. The four process parameters, that is, initial solution pH (3–5), initial arsenic ion concentration (20–100 mg/L), T. vulgaris dosage (0.10.5 g/L), and temperature (293–313 K), were considered for the process optimization through response surface methodology via central composite design (CCD) approach. According to CCD ethodology, a set of 30 experimental runs were conducted and the results were analyzed; the suggested quadratic model has well matched to the experimental results which might be used to design space according to the study of analysis of variance. The highest removal efficiency of 92.12% was attained, retaining the process conditions viz. pH 4.41, biomass dosage 0.3 g/L, initial arsenic concentration 21.33 mg/L, and temperature 298.32 K. Biosorbent morphology and chemical properties were characterized by means of fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) analysis. The presence of metal ions in the biomass of T. vulgaris after biosorption was confirmed from the SEM result. These results are significant toward the assessment and optimization of removal of arsenic ions by T. vulgaris biomass. To estimate the solute interaction and biosorption nature, the experimental data were verified with different isotherms and kinetic models. The results discovered that T. vulgaris could be a cost-effective and eco-friendly biosorbent for the removal of arsenic ions
Cotton Fabrics Treatment With Gallnut Extract (Terminalia Chebula) For Improving Color Fastness Of Alizarin Dye
Get PDFTerminalia Chebula Powder also known as Haritaki powder, karakai powder is one of the herbs used in ayurvedic medicine and terminalia chebula plants are classified under medicinal plants and these are specially referred as the king of medicine in Tibet. terminalia chebula is one of the popular and proven herbs for various types of medicinal properties. In the recent fashion of utilizing the natural and conventional techniques for modern-day usage, the karakai powder is also being used for textile applications, especially in the dyeing with natural coloring to textile goods. In this present work, the karakai powder is used as one of the mordant along with alum and other mordants for treating cotton fabrics, and these fabrics are dyed with alizarin natural dye and studied with K/S values, color fastening to washing and rubbing were studied and found improvements by application of Terminalia Chebula Powder in both pre mordanting and meta mordanting methods
A STUDY ON METALS RECOVERY FROM THE WASTE WATER EFFLUENTS IN ELECTROPLATING INDUSTRY
Get PDFRapid industrializations and urbanizations were produces very huge amounts of waste water and effluents during various unit operations and the processes. It seems to huge burden to manage to supply the sufficient quantity of water and also very difficult to manage the waste water and its effluents, and it may lead to increasing of cost and maintenance of the ETP’s. In this contest this present study attempt was done for reduction of total water consumption and to recovery of Nickel and Copper metals from the waste water effluents coming from electroplating industry were analyzed by Nickel Recovery Units and Copper Recovery Units, The metals, which are casted from aluminum wheel. The recovery units, which has a rinse bath – 1, rinse bath - 2, drag out bath, copper plating bath and cartridge filter, carbon filter, copper recovery. It was found that, after following of Nickel & Copper recovery systems, total water consumption is drastically reduced, sludge generation also reduced and also effluent generation in both the cases of nickel and copper were also reduce
Co-Crystals: A Review of Recent Trends in Co Crystallization of BCS Class II Drugs
Get PDFPoor aqueous solubility and low oral bioavailability of an active pharmaceutical ingredient are the major constraints during the development of new product. Various approaches have been used for enhancement of solubility of poorly aqueous soluble drugs, but success of these approaches depends on physical and chemical nature of molecules being developed. Co-crystallization of drug substances offers a great opportunity for the development of new drug products with superior physicochemical properties such as melting point, flow ability, solubility, stability, bioavailability and permeability, while preserving the pharmacological properties of the active pharmaceutical ingredient. Co-crystals are multi-component systems in which two components, an active pharmaceutical ingredient and a co-former were present in different stichiomentric ratios and bonded together with non-covalent interactions in the crystal lattice. This review article presents a systematic overview of pharmaceutical co-crystals. Differences between co-crystals with salts, solvates and hydrates are summarized along with the advantages of co-crystals with examples. The theoretical parameters underlying the selection of co-formers and screening of co-crystals have been summarized and different methods of co-crystal formation and evaluation have been explained
Development and characterization of fully bio‐based polybenzoxazine‐silica hybrid composites for low‐k and flame‐retardant applications
No full textIn the present work, new classes of bio‐based polybenzoxazines were synthesized using eugenol as phenol source and furfurylamine and stearylamine as amine sources separately through solventless green synthetic process routes and were fur�ther reinforced with varying percentages (1, 3, 5, and 10 wt%) of silica (from rice
husk) to attain hybrid composites. The molecular structure, cure behaviour, thermal stability, dielectric properties, and flame‐retardant behaviour of both benzoxazine monomers and benzoxazine composites were characterized using appropriate mod�ern analytical techniques. The eugenol‐based benzoxazines synthesized using furfurylamine (FBz) and stearylamine (SBz) were cured at 223°C and 233°C, respec�tively. The differential scanning calorimetry (DSC) data reveal the glass transition temperatures (Tg) of FBz and SBz were 157°C and 132°C, respectively, and the
maximum decomposition temperature (Tmax) as obtained from thermogravimetric analysis (TGA), were found to be 464°C and 398°C for FBz and SBz, respectively. The dielectric constants for FBz and SBz obtained at 1 MHz were 3.28 and 3.62, respectively. Furthermore, varying weight percentages (1, 3, 5, and 10 wt%) of
3‐mercaptopropyltrimethoxysilane (3‐MPTMS) functionalized bio‐silica reinforced the composite materials as evidenced by their improved thermal stability and lower dielectric constant. Data obtained from thermal and dielectric studies suggested that
these polybenzoxazines could be used in the form of adhesives, sealants, and compos�ites for high performance inter‐layer low‐k dielectric applications in microelectronics
Predicting correlations in abrasive waterjet cutting parameters of Lanthanum phosphate/Yttria composite by response surface methodology
No full textThe machining property of Lanthanum phosphate/Yttria prepared by the aqueous sol-gel process is eval�uated using abrasive waterjet machine. Jet pressure, Stand-off distance, and traverse speed are taken as the governing parameters on material removal rate, kerf angle and surface profile roughness. Silicon car�bide 80 mesh size is taken as abrasive. A linear cut is done on the composite of geometry Ø30 mm and 7 mm thickness for the L20 orthogonal array to study the process correlation that exhibits between the independent parameters. The equations are predicted through response surface methodology are evaluated. From the observations, jet pressure has found to have a significant effect on material removal
rate and kerf angle whereas, traverse speed significantly affects surface profile to the greater extent. The microscopic examination of the kerf surface reveals the plastic deformation surface, wear track and pres�ence of more numbers of valley and peaks regions in the top kerf surface. The study on this new func�tional composite will improve the utilization of the composite and will be a database for the researchers, to improve and extends the usage of the composite for different application
Efficiency monitoring as a strategy for cost effective maintenance of induction motors for minimizing carbon emission and energy consumption
No full textInduction motors are the major source of energy consumption in industries. Research work available on motor efficiency and energy consumption advocates the use of energy
efficient motors to reduce the power consumption. However, these motors are also prone to faults which affect its operational efficiency. Over a period of time, the propagation of fault in the motor leads to the further drop in the efficiency which increases motor running loss. This loss is generally ignored by most of the researchers and managers and is a hidden cost borne by the industries. In this paper running of faulty induction motors and its associated financial losses have been addressed. It has been assumed that for a motor running at constant load, fault propagation leads to further drop in its efficiency. Three simulated scenarios: linear, exponential and quadratic drop in efficiency have been considered for estimation of running loss. An algorithm has also been proposed for planning maintenance
actions based on operational losses due to faulty motor. This paper also highlights how efficiency and condition monitoring helps in reducing CO2 emission
Power consumption optimization strategy in micro ball-end milling of D2 steel via TLBO coupled with 3D FEM simulation
No full textThe present challenge in the manufacturing industry is to improve efficiency of production activities while reducing wastage of power consumption. Past research focused on multi response optimization of process parameters to improve performance of the process. The present study proposed an optimization-based strategy to reduce power consumption in micro ball end milling of D2 steel. As the power consumption is directly proportional to cutting forces, the process parameters such as cutting speed, feed and depth of cut were optimized to reduce cutting forces using teaching learning based optimization (TLBO) technique coupled with 3D finite element method (FEM) simulation. During the optimization, amplitude of cutter vibration and surface roughness were taken as constraints as 60µm (ISO 10816) and 2 µm (ISO 1302) respectively. Three best combinations of cutting speed, feed and depth of cut were obtained for minimum cutting force. Among them,
combination of cutting speed of 15m/min, feed of 112.5 µm/tooth and depth of cut of 85.25 µm has low power consumption of 67W with tool vibration of 36.5 µm. However, remaining two combinations were also considered to be the next best optimal cutting conditions. Numerical simulation was carried out for the three best solutions and the cutting forces and amplitude of cutter vibration were predicted. There was good agreement between simulation results and experimental results that verified the acceptance of the simulation. It was also found that the three best candidate solutions were having same the cutting speed of 15m/min (minimum cutting speed).
Hence, the induced stresses in the work piece were found to be with low values around 350Mpa