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The Stirling cryocoolers are widely used in the military and aerospace fields due to advantages such as high efficiency and compact structure. The pistons of these coolers with very small clearances operate at high speed and without lubrication. Piston failure in the coolers has often affected the operational life of the cooler. The objective of the study was to find a solution to piston failure by providing a surface coat to the pistons, carrying out their tribological evaluation, and analyse cooler thermal performance to identify the better of two coatings for field applications. In the present experimental study, a Stirling cooler developed with a cooling capacity of 0.5 W @80 K with Helium as the working fluid was integrated with surface-coated pistons and tested for its mechanical and thermal performance. On testing, DLC coating exhibits better wear resistance than TiN coating and therefore is a more suitable coating for cryocooler pistons. The present study clearly shows that DLC-coated pistons reduce power consumption and increase the number of operational hours of miniature Stirling cryocoolers. [ABSTRACT FROM AUTHOR]

Magnesium alloys have received a lot of attention as prospective bioimplant material due to their biocompatibility, mechanical properties, and biodegradability. Magnesium alloys and composites hold enormous promise as a replacement for permanent metallic implants, as there is no need for secondary surgeries after recovery. To address the corrosion and biodegradation rate of magnesium, different approaches can be adopted, such as composite preparation and surface modification. This comprehensive review emphasizes the processing route, matrix, and reinforcement for Mg alloy and composite, with the aim of enhancing their mechanical, biological, and chemical properties. It also discusses the corrosion and biocompatibility aspects of Mg alloys and composites. The article also sheds light on the potential of magnesium composites to become a dominant player in the field of bioimplant materials. [ABSTRACT FROM AUTHOR]

Background & objective. Association of multiple coronary arterial microfistulae and myocardial bridge together with concentric diffuse hypertrophic obstructive cardiomyopathy is considerably rare and we aim to highlight a similar unusual but clinically significant association in a young adult female patient with hypertrophic cardiomyopathy, presenting with progressively worsening angina on exertion. Case findings. A young 38-year-old female presented to the cardiology clinic of our institute with complaints of angina on exertion New York Heart Association (NYHA) class III for 2 years. An electrocardiogram showed left ventricular enlargement and echocardiography showed diffuse hypertrophic obstructive cardiomyopathy with the systolic anterior motion of the mitral valve and left ventricular outflow tract gradient of 40 mm Hg on Valsalva. CT coronary angiography revealed a diffuse concentric hypertrophic left ventricular myocardium with no regional wall motion abnormality, a mid-left anterior descending artery myocardial bridge, multiple coronary arterial microfistulae from distal left anterior descending (LAD) and right coronary artery (RCA) emptying to the right ventricle and dilated pulmonary artery trunk. Conclusion. In patients with hypertrophic obstructive cardiomyopathy, angina can be rarely due to coronary artery fistula and or myocardial bridge in addition to myocardial perfusion mismatch owing to hypertrophy or a combination of all. CT coronary angiography seems to be the ideal first noninvasive modality for screening and pre-intervention planning. [ABSTRACT FROM AUTHOR]

The tribological simulation can be seen as a new study problem developed through modern information technology and computer simulation technology in combination with a variety of mathematical approaches in the field of tribology. There is a need to seek new conducts and means of in-depth study of the wear quantitative law, or else, it will become difficult for a fundamental breakthrough in the prevention and control of wear to be achieved. The tribological simulation research of the typical Pin-on-Disc sliding wear test system has been carried out by the adoption of computer technology and mathematical analysis methods to provide a new wear-analysis method for the simulation of the basic tribological contact problems. In the present research conduct, an attempt has been made to establish the wear simulation model considering multiple parameters based on experimental and theoretical facts. The parameters of the computational model have been determined through the experimental test data. The simulation model has been observed to reflect the basic relationship between input and output of the pin on the dry disc sliding wear test. Experiments performed have confirmed that, under the conditions analysed, the load effect on the wear rate is more critical than the other conditions. The wear rate varies linearly with the considered load conditions. The simulations have been conducted at the different angular velocities of 50, 60 and 70 rpm. These simulations have also revealed the effect of pin diameter on the depth of wear, and the deep insight into the increase of same with an increase in surface area. [ABSTRACT FROM AUTHOR]

In this article, eco-friendly graphite has been produced from carbonised rice husk, an environmental waste. Graphite, carbon nanotube (CNT) and cast iron powder were blended to produce the hybrid coating material. This hybrid coating material was deposited over the cast iron substrate using HVOF thermal spray. The microhardness of the coated sample increased by 42% as compared to the substrate. The morphological and elemental analysis was carried out using SEM, XRD and Raman spectroscopy. The residual stresses developed in the coated sample were measured using an X-ray analyzer and found to be compressive, indicating a stable coating. A tribological investigation was carried out on a pin-on-disc tribometer at ambient, 150°C, and 300°C temperatures. The coefficient of friction and specific wear rate reduced by ≈ 62% and ≈ 47% respectively. The SEM investigation showed evidence of free graphite as a solid lubricant over the coated samples. [ABSTRACT FROM AUTHOR]

The present research investigates the thermal and corrosive behaviour of alumina-based ceramic coatings deposited on stainless steel grade 304 through the flame spray method. The microstructure of the coatings was examined using various techniques such as FESEM, EDS, and a 3D optical profilometer. The thermal conductivity of the coatings was determined by employing the hot plate method to calculate the temperature difference across the exposed coatings. Furthermore, an electrochemical test was conducted to evaluate the corrosion behaviour of the deposited coatings. The outcomes of the study reveal that the Al2O3–40%TiO2 coating exhibits significantly higher thermal and corrosive resistance characteristics in comparison to the stainless-steel substrate. [ABSTRACT FROM AUTHOR]

In this work, functionally graded material (FGM) coating that uses three powders with WC-10 wt% Co-4 wt% Cr (designated as P1), WC-12 wt% Co (designated as P2), and Ni-25 wt% Cr (designated as P3) are proposed for use over the liners of CI engines. Scanning electron microscopy and energy dispersive x-ray spectroscopy are conducted to analyze the microstructural properties, composition, and quality of the powder and the prepared coating. Results shows that the porosity of powder P3 is the highest of all three powders used in this work, and the porosity of powder P2 is smallest, whereas the porosity of powder P1 lies between P1 and P3. In addition, the hardness of the FGM coating, measured using Vicker's test, containing a combination of P1 and P2 (designated as sample 1), is higher than that of the FGM prepared with a combination of P2, P3 and P1, P3. The findings of the present work have potential implications for improving the performance and durability of CI engine liners by using an appropriate FGM coating. [ABSTRACT FROM AUTHOR]

Through this research paper, the influence of silicon nitride (Si3N4) particles incorporated with Al 7175 have been studied and reported for mechanical and physical behaviors. Various composites were fabricated by varying weight percentage (0 to 9%) of Si3N4 particles (as reinforcements) via vacuum sealed bottom pouring stir casting technique. Apart from the mechanical and physical behavioral evaluations, microstructural and micro-hardness was critically analyzed for different cast samples varying the weight percentages of silicon nitride particles. During micro-hardness evaluation of the cast samples, influence of variation in indentation load and dwell time was examined. The microstructural analysis illustrated the grain refinements with an addition of silicon nitride (Si3N4). The results exhibited significant improvements in micro-hardness, tensile strength and compressive strength by 14%, 22.76% and 25.67% respectively up to 7 weight percent with silicon nitride particles as the reinforcing phase. The micro-hardness values were observed to show a declining trend with an escalation in indentation load and dwell time. [ABSTRACT FROM AUTHOR]

It is an important concern for the researcher to understand the morphology of the Wire Cut-EDM surface. Heat-affected zones, residual stresses, and surface roughness are the main contributing factors to the underprivileged surface morphology of the workpiece. In the present study, authors investigate the effect of ultrasonic workpiece vibration in Wire Cut-EDM on the surface morphology of AISI D3 tool steel workpiece. The five parameters peak current, pulse on time, pulse off time, wire feed rate, and amplitude of vibration were selected to evaluate effects on heat effect zone, residual stresses, material removal rate, and surface roughness. In order to evaluate residual stress of the machined surface, high-resolution Field emission scanning electron microscope micrographs were used. X-ray Residual Stress Analyzer COS (α) method was also employed for the analysis of heat affected zones and micro-cracks. Design expert software is used to formulate mathematical models and derive the individual desirability values for material removal rate and surface roughness. A quadratic model is obtained that might suitable for all proposed objective functions. At lower range of vibration of amplitude of 15 µm resulted in better surface characteristics; on the other hand, high vibration amplitude resulted in poor machining stability because of critical wire breakage. The residual stress results indicated that the higher values of peak current and pulse of time gave rise to undesirable machined surface quality characteristics. Detailed 3D Debye–Scherrer ring distortions and high peak strength, residual stress data were indicators of a damaged workpiece surface with large craters, micro-cracks, and high tensile residual stress. [ABSTRACT FROM AUTHOR]

Burnishing is a cold working technique used as a surface enrichment to meet the desired surface properties of the workpiece. It improves the visual properties, dimensional tolerances, fatigue strength, surface roughness, and hardness of the work material by applying appropriate pressure through a complex ball burnishing tool to cause plastic deformation. In the current work, the mathematical modeling of the burnishing process was carried out to predict surface roughness by considering the process parameters such as contact radius, penetration depth, and elastic rebound. Further, a customized tungsten carbide (W.C.) insert having a hardness of 80 HRC was developed for the burnishing operation. The micro-hardness of the resulting burnished surface improved from 44 to 48 HRC. The surface quality of the tungsten carbide insert improved by up to 17.1 nm through polishing. Several experiments were performed by selecting appropriate process parameters using developed model feedback. The surface quality of the workpiece improved by up to 45 nm, which resulted in automatic improvements in fatigue strength up to seven times that of the virgin material. The results predicted from the mathematical model were in good agreement (less than 5% deviation) with the experimental results. This study helps to understand the surface formation mechanism in the burnishing process in more detail. Additionally, the achieved results show a significant improvement in the surface finish (~95%), indicating the potential of the burnishing process and how fast and cost-effective it is. The novelty of this paper lies in the improvement in surface roughness and the validation of our mathematical model results with the experimental results. [ABSTRACT FROM AUTHOR]

The aim of the present study is to develop eco-friendly, low cost and light weight plastic based composite material using eggshells (bio-waste) ash as filler material. The study describes the development of carbonized eggshells loaded hybrid glass-jute fibre reinforced (GJFR) polyester bio-composites and reports the effect of fillers loading on its wear behaviour and mechanical properties. Carbonized eggshell ash powder as a filler, glass and jute fibre rovings as hybridized fibre and unsaturated polyester resin as a matrix material were used for the development of novel FRP composites using the pultrusion process. Eggshells ash powder was used in different weight (wt) % as 3.5 wt%, 6.5 wt%, 9.5 wt%, 12.5 wt%, and 15.5 wt%. A pin-on-disc tribometer was employed to analyse the wear behaviour. Two variable load conditions as 30 N and 50 N were selected to wear test runs while sliding speed, sliding distance, and track diameter as 3 m/s, 1500 m, and 60 mm respectively were kept constant. The developed hybrid composites with 9.5 wt% and 3.5 wt% carbonized eggshells filler involvement showed maximum and minimum tensile strength as 75 MPa and 62 MPa respectively. The composites with 12.5 wt% and 3.5 wt% eggshells fillers showed maximum and minimum compressive strength as 99 MPa and 49 MPa respectively. The maximum wear resistance was exhibited by composites with 9.5 wt% filler loading and at 50 N applied load conditions. The carbonized eggshell fillers inclusion in a limited amount was recommended to strengthen the wear resistance of the GJFR polyester composites in combination with tensile and compressive strengths. A scanning electron microscope study was conducted to notice the wearing procedure and tensile and compressive fracture of the GJFRP composites. [ABSTRACT FROM AUTHOR]

Hybrid metal matrix composites are the modern age materials that are extensively employed in automotive, civil construction, and bio-medical sectors. These composites should be eco-friendly, cost-effective, and exhibited with good mechanical properties. Therefore, this paper proposes a novel hybrid metal matrix composite with Al7075-T6 as a base matrix and SiC/CR/MoS2 as three distinct reinforcements, which is fabricated through advanced vacuum-sealed bottom pouring stir casting (BPSC) technique. The various process parameters chosen for the experimental study at room temperature are silicon carbide (SiC) content (3.5 and 4.5 wt.%), crumb rubber (CR) content (0.3, 0.6, and 0.9 wt.%), molybdenum disulfide (MoS2) content (3.5, 4.5, and 5.5 wt.%), stirring speed (580, 600 and 620 rpm), stirring time (2, 5 and 8 min) and pouring temperature (670, 700 and 730 °C). The design of experiments (DoE) with Taguchi L18 orthogonal array and pooled analysis of variance (ANOVA) are also conducted to investigate the influence of process parameters on densities, porosity level, surface morphology, micro-hardness, and tensile strength of the synthesized composites. Experimental results have validated that the density and porosity are significantly revamped with the selected process parameters. In addition, the microscopic images of synthesized composites have demonstrated the better surface morphology because of the uniform dispersion of reinforcements over the base matrix which is examined through an optical microscope, x-ray diffraction (XRD), and field emission scanning electron microscope with energy-dispersive x-ray spectroscopy (SEM/FESEM-EDS) techniques. In contrast to monolithic alloy, the synthesized hybrid composite having the composition of Al7075-T6 + 3.5%SiC+0.3%CR + 5.5%MoS2 (i.e. sample no.3) attains maximum improvement with porosity content is decreased by 38.74% whereas; micro-hardness and tensile strength are increased by 34.66% and 27.82%, respectively. Besides, the pooled ANOVA has also predicted the percentage contribution of the selected process parameters for micro-hardness and tensile strength. [ABSTRACT FROM AUTHOR]

Aluminum alloy-based metal matrix composites (AMMCs) are the most common material used in the field of automotive sectors because of their lightweight, economical, high strength-to-weight ratio, anti-corrosive properties, and large-scale availability. In the present study, Al7075-T6 as a base matrix with silicon carbide (1.5, 2.5, and 3.5 wt.%), graphite (2, 3, and 4 wt.%), and S-glass fiber (3, 4, and 5wt.%) as three distinct reinforcements was used for the fabrication of aluminum-based hybrid metal matrix composites through vacuum sealed stir casting technique. Taguchi design of experiments L9 orthogonal array and analysis of variance (ANOVA) have been adopted to investigate the influence of selected input process parameters such as silicon carbide (SiC), graphite (Gr), and S-glass fiber content on the output response parameters such as micro-hardness and impact strength. The experimental study revealed that micro-hardness and impact strength of synthesized composite have been enhanced by an amount of 31.40% and 33.33%, respectively, as compared with monolithic Al7075-T6 base alloy. In addition, the microstructure of fabricated hybrid AMMCs based on optical micrographs, SEM-EDS measurement along with XRD examination (for phase identification) showed a uniform dispersion of reinforcement particles over a base matrix. Furthermore, a fit regression model was prepared to develop the relationship between the variable process parameters corresponding to the response outcomes in terms of micro-hardness and impact strength. [ABSTRACT FROM AUTHOR]

In the present area, the outbreak of COVID-19, customer behavior have been seen toward their individual specific need, which encourages advanced-manufacturing industries to provide mass personalization of goods and services. The Covid-19 crises bring opportunities for industries and service providers to enhance their capability for a fault-free environment, zero failure, anti-fragile, and improve production capacity. The present paper provides an overview of the sustainability of Industry 6.0 in a global perspective with vision, objective, and transformation of Industrial Revolutions. The sole aim of industry 6.0 is to seizure the new technologies, which can be applied worldwide and deliver wealth, prosperity away from the job and provide growth to nations across all planetary boundaries. This revolution would promote living harmony with nature, support the principle of sustainability where technology would not be a thing, and promote the human virtual digital twin where all can simultaneously see physical goods and virtual product information. [ABSTRACT FROM AUTHOR]

The present investigation has been carried out with the aim of determining the frictional and wear behavior of porous copper-based composites. The porous copper-based composites have been prepared by using a novel approach for bearing applications, where the mixture of copper oxide and copper powder is blended with the hybrid 2D material, i.e., reduced graphene oxide-MoS2 (rGO-MoS2) by ball milling. The composites were sintered using microwave sintering technique having different compositions (0, 0.5, 1.0, 1.5 and 2.0 wt.% rGO-MoS2), wherein rGO-MoS2 served as the genesis of porosity. The density and hardness decreased with increase in rGO-MoS2 content, and the relative density up to 62% is achieved. The tribological behavior was studied at the different loads of 4, 6, 8 and 10 N and constant sliding speed of 0.5 m s−1 against EN31 ball counterface, while testing has been conducted under dry sliding and mixed lubricated conditions. Composites exhibit the low frictional characteristics as compared to the base material, and an increase in coefficient of friction and wear rate is observed with increase in load. The worn surface analyzed by the scanning electron microscopy and energy-dispersive x-ray spectroscopy revealed the oxide layer formation, abrasive wear and adhesion as major wear mechanisms in dry sliding conditions. Tribo-oxide layer formation and retention of lubricant in the pores account for the low friction and wear of the composites under single drop lubrication. [ABSTRACT FROM AUTHOR]

In this research work, the deposition of diamond coating was done on the tungsten carbide (WC) substrate utilizing the the thermal Chemical Vapour Deposition (CVD) technique. The carbon precursor used for growing the diamond on the tungsten carbide (WC) substrate material was sugarcane bagasse. The tribological properties of deposited diamond coating were studied examined in this paper. For characterization of the developed coating, Field Emission Scanning Electron Microscope (FESEM), Raman spectroscopy and X-ray diffraction (XRD), were used to characterize the developed diamond coating on the substrate material. These processes were used to confirm the presence of diamond coating on the substrate. For inspecting the hardness of the developed diamond coated and un coated samples, the tests of micro-hardness were also executed. The values of the Vickers hardness for the un-coated and the diamond coated substrates were found to be 964.95 HV to 1457.48 HV respectively. This depicted a rise of 51% in the hardness of the un-coated WC inserts. As per ASTM G-99 standards tribological behaviour of the developed coated substrate was also the scope of this work using a pin-on-disc tribometer. The tribological tests showed improvement in the wear resistance of the diamond coated WC inserts as there was a decrease in the value of wear by 57.84 %. The value of the coefficient of friction (COF) also found to be decreased by 51.48%. This paper presents a combined study of using tribological tests and morphologic study showing the advantages of coating diamond on the tungsten carbide (WC) substrate. [ABSTRACT FROM AUTHOR]

Powder mixed near dry electric discharge machining is an advanced hybrid form of electric discharge machining method which makes minimum use of dielectric oil and is quite sustainable in machining terms. In this article an approach has been made to optimize the variable parameters such as tool type, metallic powder concentration, dielectric mist pressure, and mist flow rate in order to study their effect along with their range in order to enhancing the machining performance in terms of increased material removal rate (MRR), improved surface finish, improved micro-hardness, reduction of residual stress and tool wear rate. Analysis of variance along with Taguchi L9 methodology was utilized for conducting experiments and it was revealed by the confirmation experiments that by this technique, the optimized results for improved material removal rate, improvement of surface finish, enhanced micro-hardness, reduced residual stress and tool wear rate were 0.63 (mg/s), 0.79 (pm), 249 (HV), 286 (MPa) and 1.07 (mg/min) respectively. The optimized values were obtained at Tool diameter (3mm), flow rate of mist (15 ml/min), concentration of metallic powder (8 gm/l) and mist pressure (0.5 MPa) of dielectric medium. [ABSTRACT FROM AUTHOR]

Abrasive Flow Machining (AFM) process has been a useful technique for deburring and polishing of the surface and edges through the abrasive laden media. The surface material has been removed in form of micro chips due to abrasion action of sharp cutting edges abrasive particles. A large amount of force and energy has been lost due to frictional forces between the surface and abrasive particles in AFM process. A new hybrid form of AFM process named as thermal additive centrifugal abrasive flow machining (TACAFM) has been discussed in the present investigation, which utilized the spark energy to melt the surface material. A lesser amount of force has been required by the abrasive particles to remove the molten material from the surface and also minimized the energy loss. In the present investigation central composite design response surface methodology has been used to plan and conduct the experiments using Design Expert® 11 software. Experiments have been performed to analyze the effect of input process variables such as current intensity, duty cycle, abrasive concentration, rotational speed of the electrode and extrusion pressure on scatter of surface roughness, micro hardness and % improvement in Ra of the workpiece. Also the finished surface of the brass work piece has been characterized for the microstructure study using SEM and XRD analysis. From the experimental results it has been found that duty cycle has the most significant effect towards Scatter of surface roughness with a contribution of 17.5 % while current has been contributed largest as 85.17 % towards micro hardness. Also it has been observed that current has contributed largest as 21.88% against the % improvement in Ra. The optimum scatter of surface roughness, micro hardness and % improvement in Ra has been observed as 0.15 pm, 345.95 HV and 39.52 % respectively. [ABSTRACT FROM AUTHOR]

The current scenario of industrialization requires need for higher productivity which is met by advanced material removal process, i.e., abrasive flow machining (AFM) in which the internal surfaces of the workpiece is machined to higher accuracy level with the help of abrasive laden media. In this paper, the conventional AFM setup has been made hybrid using electrolytic and magnetic force arrangement alongwith rotational effect in order to achieve better results in terms of material removal and surface roughness. The newly developed in-house polymer media were utilized in the process and the input parameters taken during experimentation were magnetic flux, electrolytic rod size and shape, rotational speed, polymer media, abrasive particles and extrusion pressure. It was found that the material removal and surface roughness improvement were more in electrochemo magneto rotational AFM process compared to conventional AFM process. The experimental values were in confirmation with those obtained in the optimization techniques applied, i.e., Taguchi L9 OA, Matlab fuzzy logic and GRA-PCA. In addition, the hybrid mathematical model was developed and effect of different forces occurring in the process and computational flow analysis of media have been explained. [ABSTRACT FROM AUTHOR]

Powder-mixed near-dry electric discharge machining (PMND-EDM) process have been attracting attention in the manufacturing community because of its capability to produce the end products with better surface quality characteristics and improved machining rate. Present work is an effort to understand the influence of process variables like tool diameter, flow rate of dielectric mist, concentration of metallic powder and mist pressure of dielectric medium. Taguchi method orthogonal array L9 was used for the conduction of experiments. Analysis of variance (ANOVA) was employed to find out the significance of process parameters. The results reveal that the optimum process parameters for the experimental condition for maximum MRR (0.11 mg s-1)was at tool diameter at A1 (2mm), flow rate of mist at B3 (15 ml min-1), concentration of metallic powder at C3 (25 gm l-1) and mist pressure of dielectric at D3 (0.6 MPa). It has been also concluded that metallic powder was responsible for surface modification to achieve higher micro-hardness value up to 530.10 Vickers hardness number along with refined surface characteristics. [ABSTRACT FROM AUTHOR]

The products processed by Electrical Discharge Machining (EDM) leave some undesirable effects, the most prominent of which is Residual Stress (RS). These RS affect fatigue behavior, dimensional stability, and stress corrosion. The latter is the cause of failure of processed products. It has been observed that products obtained by Powder Mixing Near Dry Electric Discharge Machining (PMND-EDM) have relatively low RS values. The purpose of this research is to minimize the RS caused in the machined workpiece (EN-31) by optimizing the process parameters that significantly affect the machining characteristics. The selected parameters were tool diameter, mist flow rate, metal powder concentration, and mist pressure, and the selected workpiece was EN-31 because it has ideal mechanical properties and is widely used in manufacturing. The minimum value of RS at optimized values of process parameters was found to be 106.32 MPa. [ABSTRACT FROM AUTHOR]

This study aims to identify the root-knot nematode (RKN) at seven olive plantations in Rajasthan (India), and understand the possible spread of RKN and its bacterial parasite, Pasteuria penetrans through olive planting material (OPM). We identified the RKN as Meloidogyne javanica based on perineal pattern morphology and species-specific SCAR marker. RKN was prevalent at all the locations with high natural incidence (50–90%) of P. penetrans in the females dissected from unstained roots. An artificial exposure of air-dried soil of seven locations to healthy juvenile (J2) of M. javanica showed that the trend was consistent with the natural population. We conclude that root hardening media comprising of dried river sand and nematode-infested soil mixed at the secondary site (Jaipur) in India possibly resulted in M. javanica infection of OPM along with P. penetrans. Our study suggests that P. penetrans proliferated to suppressive levels and kept the nematode population below damaging levels. [ABSTRACT FROM AUTHOR]

Electrical discharge machining (EDM) is a non-conventional method of machining hard materials with intricate shapes. Near-dry electric discharge machining (ND-EDM) is an advanced method of EDM which is eco-friendly and is more efficient in terms of material removal rate (MRR) than traditional EDM. In this research, an approach has been made to perform a new electrical discharge machining operation on EN-31 steel which utilizes metallic powder as an additive along with a gaseous dielectric (for example air) in ND-EDM. This advanced method of machining is known as powder mixed near-dry EDM. This study involves modeling for output process parameter—Material Removal Rate. The mathematical model was developed using the approach of Gaussian heat distribution. FEM modeling was done on ANSYS WORKBENCH 16.0 module. The experiments were performed and comparative study was done between the results obtained by modeling and experiments. The maximum experimental MRR was 7.68 mm3/min, and the error percentage between experimental, mathematical and FEM was under 30%. It was concluded that the modeling was done successfully and results obtained do comply with the methodology of the research. [ABSTRACT FROM AUTHOR]

Effluent from full-scale and bench-scale upflow anaerobic sludge blanket reactors (UASBRs) was aerated by surface aerator. The monitoring parameters used for process were oxidation reduction potential (ORP), dissolved oxygen (DO), chemical oxygen demand (COD) and biochemical oxygen demand (BOD). Experiments were conducted on effluents of bench-scale 56-L UASB reactor as well as on the effluents from four UASB-based sewage treatment plants (STPs) of capacities ranging from 34 to 70 ML/d (million liters per day). The linear relationship between DO and ORP indicates the sensitivity of ORP. The rate of DO transfer depends on ORP, DO deficit, nature and concentration of BOD or COD. The ORP values increased with aeration time indicating improvement in redox status. The oxygen demand of anaerobically treated effluent proceeds in three-stage initial S-BOD exertion followed by CBOD exertion and subsequently NBOD exertion. The optimum condition for BOD, COD and sulfide removal was 120–140 min characterized by DO content of 4–5 mg/L. Sulfides removal rate of 80% and BOD of 30 mg/L desired discharge standards were obtained. [ABSTRACT FROM AUTHOR]

Plant-parasitic nematodes cause severe damage to the various agricultural crops, leading to economic losses for farmers. Therefore, identification and development of novel and environmentally benign nematicides is critically important. In this study, a silver nanoparticle (AgNP) formulation was synthesized, characterized, and investigated as a potential nematicide against rice root-knot nematode, Meloidogyne gramnicola, on rice (Oryza sativa). A series of lab assays (water and sand screening) and glasshouse experiments (using soilless system, autoclaved soil, and naturally infested soil) were conducted to examine the nematicidal effects of AgNP. The results from lab assays revealed 0.1 μg/ml as the minimum concentration for 100% irreversible nematode mortality after 12 hr in the water screening test. However, results from the sand screening test indicated 100% nematicidal effect of AgNP at 2 μg/ml after 24 hr of incubation. In glasshouse assays in soilless system of rice cultivation, 1 μg/ml concentration of AgNP applied directly to the trays achieved significant suppression of root gall formation. The effective dosage to kill nematodes in field soil assays was determined to be 3 μg/ml, which is lower than the value of 150 μg/ml reported in the literature. No visible adverse effect of AgNP was observed on seed germination or plant growth in all the experiments. The results indicate that AgNP has effective nematicidal activity against M. graminicola in rice. [ABSTRACT FROM AUTHOR]

Background: Sodium‐glucose co‐transporter‐2 inhibitors are novel antidiabetes drugs that act via inhibition of renal glucose reabsorption. This action causes osmotic diuresis, reduces intravascular volume and is associated with various adverse effects. In the present paper, we describe the first report on the unmasking of underlying polycythemia vera by canagliflozin in a person with Type 2 diabetes mellitus, which was temporally related to the use of the drug. Case report: A 51‐year‐old obese man with Type 2 diabetes was prescribed canagliflozin 100 mg for control of his glycaemia. He presented 6 months later with asymptomatic elevation of his haemogram measurements (haemoglobin: 16.9 g/dl; haematocrit: 55%; red cell number: 8.1 million/mm3; total leukocytes: 23010/mm3; platelet count: 9.7 *106/mm3). He had no history of smoking, exposure to high altitude or other drugs. Subsequent investigations revealed myeloproliferative neoplasm (polycythemia vera) on trephine biopsy of bone marrow, normal erythropoietin level and JAK2V617F positivity. Because of the possibility that the underlying condition had been unmasked by canagliflozin, the latter was stopped. This led to a remarkable improvement in the man's haematological profile, with no other significant intervention. The man subsequently restarted the drug of his own accord, causing his haematological profile to worsen again and thereby posing a challenge in monitoring of both polycythemia vera as well as diabetes mellitus. Conclusion: This report brings to light unmasking of a new adverse effect of sodium‐glucose co‐transporter‐2 inhibitors in clinical practice caused by volume loss, apart from hypotension and falls. What's new?: The use of sodium‐glucose co‐transporter‐2 (SGLT2) inhibitors is associated with a decrease in intravascular volume and a consequent increase in haematocrit levels.A rise in haematocrit level of >11% with the use of SGLT2 inhibitors should raise suspicion of myeloproliferative neoplasms.Discontinuation of the drug is then warranted in order to optimize monitoring of therapy for myeloproliferative neoplasms and to prevent thrombosis. [ABSTRACT FROM AUTHOR]

This experimental examination exhibit a novel Hybrid Wire electrical discharge machining (H-WEDM) process of ultrasonic vibration combined with traditional Wire-EDM. The metal cutting for form tool and extrusion die with WEDM is liked to give better surface morphology. The effect of residual stresses has been dissected for H-WEDMed machined surface alongside the surface roughness and erosion rate to enhance surface integrity and longer service life of High Carbon High Chromium D2 tool steel. The process parameters chose for this investigation are type of vibration continuous/discontinues, amplitude of vibration, workpiece dimension, duty cycle, peek current and wire feed rate with objective to optimize the residual stresses and erosion rate. Portable X-ray Residual Stress Analyzer, a non-destructive X-ray analyzer is used to measure the residual stress efficiently by detecting the full Debye ring data from a single incident X-ray angle and Non goniometer stage influence on the measurements. An endeavor was made to compare the residual stresses for continuous/discontinues vibration and without vibration. The impacts of amplitude of vibration, peak current, duty cycle and wire feed rate variations on erosion rate was study using Taguchi method. From experimental study, it was observed that discontinuous vibration enhances the erosion rate and diminishes the resultant stresses. High Peak current and duty cycle altogether deteriorate the surface texture, which creates high tensile residual stresses because of debris and micro cracks. The optimum value of residual stresses 86.53 MPa and material erosion rate 6.45 mm/min was achieved using H-WEDM. [ABSTRACT FROM AUTHOR]

This paper is an endeavor to comprehend an interactive learning process of ultrasonic vibration assisted Electrical Discharge Machining (USEDM) process performance index. The factors influencing the USEDM process are identified and analyzed, through a logical and systematic framework of graph theory and matrix approach. The interdependency of factors are distinguished and examined. A systematic model of USEDM performance index is proposed to utilize graph theoretic approach (GTA). The performance index for USEDM is obtained so from the matrix model and digraphs to comprehend the power of subjective factors affecting. Factors and sub-factors impacting the performance are perceived and collected into five essential groups e.g. flushing, cavitation, abnormal discharge, dimensional accuracy and surface morphology. GTA framework reveals that the flushing, surface morphology and dimensional accuracy impact the basically ascertains, however cavitation effect can in like manner be unequivocal variables for USEDM performance index regard. [ABSTRACT FROM AUTHOR]

Most of the existing multi-response optimization approaches focus on subjective and practical know how of the process. As a result some confusions and uncertainties are introduced in overall decision making process. In this investigation, an approach based on a Utility theory and Taguchi quality loss function has been applied to low-pressure cold spray process to deposit copper coatings, for simultaneous optimization of more than one response characteristics. In the present paper, three potential response parameters i.e. coating density, surface roughness and Micro hardness have been selected. Utility values based upon these response parameters have been analyzed for optimization by using Taguchi approach. The selected input parameters of powder feeding arrangement, substrate material, air stagnation pressure, air stagnation temperature and stand-off distance significantly improves the Utility function (raw data) comprising of quality characteristics (coating density, surface roughness and micro hardness). The percentage contribution of the parameters to achieve a higher value of utility function is: substrate material (64.59%), air stagnation pressure (16.35%), powder feeding arrangement (6.92%), air stagnation temperature (6.49%) and stand-off distance (1.84%) respectively. [ABSTRACT FROM AUTHOR]

Fourteen populations of Meloidogyne graminicola were collected from different agroecological regions of India. Morphological and morphometrical comparisons were made for various nematode life stages. Three populations (Hisar, New Delhi, and Samastipur) were different from typical M. graminicola on the basis of the length of eggs; J2 length, a-value, hyaline tail portion; male length, distance up to excretory pore, spicule and gubernaculum lengths; female length and width, stylet length, distance up to excretory pore, EPST (distance of excretory pore from anterior end / stylet length [females]) ratio, and vulval length. Morphological and morphometrical comparison with closely related species M. graminis, M. oryzae, M. salasi, M. triticoryzae, and M. lini clustered these populations into two groups: Anand, Bhubaneswar, Hyderabad, Jammu, Jorhat, Kalyani, Kanpur, Ludhiana, Mandya, Palampur, Vellayani grouped with M. graminicola, M. triticoryzae and M. salasi; whereas, Hisar, New Delhi, Samastipur grouped with M. oryzae and M. graminis. Molecular phylogenetic analysis using internal transcribed spacer (ITS) suggested that in spite of morphological differences, these populations belonged to M. graminicola. [ABSTRACT FROM AUTHOR]

In present research work, pultrusion process is used to develop jute fibre-reinforced polyester (GFRP) composite and experiments have been performed on an indigenously developed pultrusion experimental setup. The developed composite consists of natural jute fibre as reinforcement and unsaturated polyester resin as matrix with hybrid filler containing bagasse fibre, carbon black and calcium carbonate (CaCO). The effect of weight content of bagasse fibre, carbon black and calcium carbonate on tensile strength of pultruded GFRP composite is evaluated and the optimum hybrid filler composition for maximizing the tensile strength is determined. Different compositions of hybrid filler are prepared by mixing three fillers using Taguchi L orthogonal array. Fifteen percent of hybrid filler of different composition by weight was mixed in the unsaturated polyester resin matrix. Taguchi L orthogonal array (OA) has been used to plan the experiments and ANOVA is used for analysing tensile strength. A regression model has also been proposed to evaluate the tensile strength of the composite within 7% error by varying the above fillers weight. A confirmation experiment was performed which gives 73.14 MPa tensile strength of pultruded jute fibre polymer composite at the optimum composition of hybrid filler. [ABSTRACT FROM AUTHOR]

Abrasive flow machining is a fine finishing process, mainly for the finishing of complex internal/external surfaces of metallic parts. Like most of the finishing processes, this process is also a slow process due to low material removal rate. Hybridization of abrasive flow machining process (AFM) with other non-conventional machining (NCM) processes is being explored in the recent times, so as to overcome the main limitation of low material removal in the AFM process and to satisfy the stringent finish/functional requirements. The present study is about the development of a novel hybrid of electrochemical machining (ECM) and abrasive flow machining (AFM), for the fine finishing of internal holes or prismatic recesses. The new process has been termed as electrochemical-aided abrasive flow machining (ECAFM) process, and higher abrasion of the material was observed in this process due to the synergetic effect of ECM and AFM processes. Further in the present investigation, the various process parameters have been optimized for the response characteristic of material removal, based on Taguchi method and using standard L orthogonal array (OA) for the plan of experimentation. Overall, the ECAFM process has a very promising future in the industries in terms of its ability to finish fast even if the component is thin/delicate and made of hard alloys. [ABSTRACT FROM AUTHOR]

Abstract: Introduction and aims: Liver transplant surgery is often associated with considerable bleeding. This study was undertaken to analyse the average blood component consumption and the effectiveness of preoperative laboratory assessment and Model For End Stage Liver Disease (MELD) score in the estimation of transfusion requirements in Living Donor Liver Transplantation (LDLT). Material and methods: Univariate and stepwise regression analysis were employed to establish the significance of correlation of the preoperative laboratory variables, including haematocrit, platelet count, INR, total bilirubin, serum creatinine, blood urea and MELD score with the total consumption of Packed Red Cells (PRCs), cryoprecipitates, aphaeresis platelets and Fresh Frozen Plasma (FFP). Stepwise discriminant analysis was used to identify those preoperative factors which have a significant predictive value for the total consumption of each blood component and these results were employed to construct separate prediction models for the utilization of each blood component and the respective R square values were determined. Results: A total of 509 patients were included. On an average, 8.44 units (SD = 6.11) of PRCs, 2.58 units (SD = 2.95) of cryoprecipitates, 0.81 units (SD = 1.16) of aphaeresis platelets and 2074.85 ml (SD = 1240.20) of FFP were consumed per LDLT. The blood component prediction models could be employed to accurately predict the total utilisation of PRCs, cryoprecipitates, FFP and aphaeresis platelets in 23, 22.6, 17.8 and 20.7 per cent of our patients, respectively. Conclusion: We have been able to identify those preoperative factors which can be employed to predict the consumption of various blood components in living donor liver graft recipients. These variables were further employed to construct prediction models, separately for each blood component. We also identified those preoperative variables which significantly influence the in hospital mortality and PLOS in LDLT recipients. [Copyright &y& Elsevier]