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In the advancement phase of science and technology, it becomes an important issue to opt for non-traditional resources to save fuel or energy. Due to increasing trend in oil price, restrictions on air pollutions, and additionally, to have more financial gains, researchers are concentrating on replacing conventional material with some other substitute material. In this paper, conventional marine propeller material is replaced by glass fiber reinforced plastic (GFRP) and carbon fiber reinforced plastic (CFRP) to investigate their effect on the blade loadings with respect to the number of blades. Here, four propellers are considered with one, two, three and four number of propeller blades for numerical investigation, and the obtained results are analysed. It may be noted here that the number of propeller blades is limited up to four keeping in mind about the increase in manufacturing cost and additionally, the blockage effect due to increased number of blades. It has been noticed that stress, strain and deflection produced are less in a GFRP propeller in comparison to those obtained for a CFRP propeller, and it gradually decreases with the increase of number of propeller blades.

The present work consists of modelling and stress analysis of a three-bladed underwater vehicle propeller. Since operational costs for underwater testing are very high, a high ending software is preferred for modelling and for obtaining first-hand information on propeller performance. Static structural analysis is carried out computationally after considering suitable boundary conditions. The main objective is to carry out a comparative study of stresses on propellers made from two different composite materials–carbon/glass fibre reinforced plastics (CFRP/GFRP). In recent times, composite materials are more efficient as propeller blade material than conventional metallic materials due to their lightweight, high strength, and long durability. From the analysis, it is observed that stresses, as well as deflection on GFRP are comparable to those on CFRP propeller with lesser cost involvement. Modal analysis is also performed to find natural frequency and mode shape in each case.

Algal oil was obtained from microalgae chlorella vulgaris. The microalgae was cultivated in open pond system. Upon harvesting, the biomass was centrifuged and dried. The algal oil was obtained by a solvent extraction method using n-hexane as solvent. By this method 28% of algal oil is obtained from dry algae biomass. Transesterification process is carried out to produce algae biodiesel by adding potassium hydroxide and methanol. The biodiesel yield obtained is 85%. The testing of algae oil and algae biodiesel is carried out to know the calorific value, density and kinematic viscosity. Performance and combustion parameters were analyzed on a Kirloskar single cylinder direct injection compression ignition engine. The compression ratio is 17.5. It develops 5.2 kW brake power at rated speed of 1500 rpm with diesel as fuel. The engine is initially run on diesel fuel to generate baseline data and after that it is run on straight algae oil and algae biodiesel. Similar loading conditions are used for all the fuels. The Brake Specific Fuel Consumption, Brake Specific Energy Consumption, Brake Thermal Efficiency, Smoke Opacity, CO, HC, and NOx were studied. The trials conducted on diesel engine with algae oil and algae biodiesel show that results are comparable to diesel fuel.

In present era, the scarcity of fossil fuels and their negative impact on environment drive the research in the field of alternative fuels, Biodiesel is one of such promising alternative fuel that are used in automobile, gas turbine, boiler and other furnace application. In the present study, an airblast atomizer along with axial swirler (swirler no. 0.76) is employed to investigate the combustion characteristic of Jatropha methyl ester (JME) and its diesel blends on gas turbine like combustor. During the experiment, fuel mass flow rate (40 ml/min), Air to liquid ratio (ALR=2) and air temperature (600K) are kept constant. For different equivalence ratio, spray and flame characterization, flame temperature, combustion efficiency and emission parameters such as carbon dioxide (CO2), Carbon monoxide (CO), Nitrogen oxide (NOx) and unburned hydrocarbon (UHC) are determined. It is revealed that the flame temperature increases with increase in JME percentage in diesel and major pollutant such as CO, CO2 and UHC emissions decreases but it has been noticed that compared to diesel the NOx emission increases with increase in fraction of JME. The obtain results prove that biodiesel can be used as fuel for production of power in gas turbine instead of fossil fuels.

The microalgae oil obtained from chlorella protothecoides was converted to microalgae oil methyl ester using transesterification process. The physical and chemical properties of microalgae oil and microalgae oil methyl ester were tested and it was observed that chlorella protothecoides oil and microalgae oil methyl ester can meet the ASTM standards for the characteristics tested. In this research work performance, combustion and emission parameters were analyzed on a Kirloskar single cylinder direct injection compression ignition water cooled diesel engine having capacity 5.2 kW fueled with diesel, microalgae oil and microalgae oil methyl ester. The engine showed the reduction in emission of CO, UBHC, NO x and smoke opacity as compared to those of diesel when fueled with microalgae oil and microalgae oil methyl ester. A general trend of decrease in the brake thermal efficiency with the use of microalgae oil and microalgae oil methyl ester was observed.

Arrayed microrods are used to drill array of microholes in workpieces by Micro electrical discharge machining (μEDM). In comparison to a single microrod, the use of an array of microrods enables drilling of multiple microholes in lesser time, and hence it offers a higher productivity. The present work focuses on the effect of tool wear on the dimensions of the machined array of microrods through reverse micro electrical discharge machining (R-μEDM). The effects of the input parameters such as voltage, capacitance and feed rate on the obtained length and diameter of the microrods have been investigated. This study introduces a simple analytical model to evaluate the amount of tool wear and material removal from a bulk rod. As the levels of voltage and capacitance increase from lower to higher, the tool wear increases by 574%. At lower levels of voltage and capacitance, a straight array of microrods with a longer length of about 1.961 mm is obtained. On the other hand, at higher levels of voltage an...

Plasma Arc Welding PAW is one of the important arc welding process commonly using as aerospace, medical, power plants, and automobile industry. Especially stainless steel 316L SS316L has been successfully utilized in many sectors because of its excellent corrosion resistance, self healing property, and biocompatibility, high fatigue life and creep resistance. The paper focuses on weld quality characteristics like weld bead geometry, grain size, hardness and ultimate tensile strength of PAW welded joints of austenitic stainless steels AISI 316L. From the analysis carried out it is noticed that AISI 316L has achieved sound weld bead geometry, good tensile strength and hardness. Welding of Low Nickel Chrome manganese Austenitic is an emerging area of research. Due to nickel price volatility, there was been increased interest in no nickel or low nickel economical grades of stainless steel. Chrome manganese austenitic "standard 200 series" and ferritic stainless steel "standard 300 series" grades with well defined technical properties have proved acceptable materials for specific applications for many years. This increase in the use and production of these low nickel grades is not currently matched by a proper level of user knowledge. So there is a risk that they may be used in unsuitable applications. It is very important to cultivate the method of fabrication like welding. This paper looks at the behaviour of low nickel chrome manganese austenitic stainless steel in terms of microstructure and sensitization effects upon welding by PAW process. In this project, we performed 5 mm thick AISI 316L bead on and joint using PAW. Further study the geometric analysis, microstructure, micro hardness, tensile strength, SEM analysis and TAGUCHI analysis of the welded workpieces and analyzed the benefits and shortcoming methods. Arka Ghosh | Mr. T. K. Bhattachraya | Mr. N. V. Deshpande | Dr. Sushovan Basak "Microstructural and Mechanical Properties Analysis of Plasma ARC Welded 316L Austenitic Stainless Steel Joints without Addition of Filler Material" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd26478.pdf

In today’s world, microstructures have a wide range of applications in the field of biomedical devices, aerospace engineering, MEMS device elements, etc. In the recent years, reverse micro-electro-discharge machining (R-µEDM) has evolved from µEDM that has become one of the promising technologies to fabricate precise components and microstructures of various shapes with high aspect ratio. In this work, micro-tools (rods) of average size (diameter) 182 µm have been machined using copper sheet from bulk tungsten rod of 800 µm diameter by R-µEDM process. Moreover, Taguchi’s L16 orthogonal array has also been applied for designing the experiments. Feed rate, capacitance and voltage are considered as the parameters of the process. The response parameters such as machining time, erosion rate and dimensional variation have been analyzed in detail for different combinations of the process parameters. It is a well-known fact that the tool wear is the main culprit and responsible for the error in the micro-rods. Dimensional error has been quantified over the entire length of the micro-rods through the measurement process, and the minimum standard deviation is found to be 1.13 µm at a feed rate of 5 µm/s, capacitance of 1000 pF and voltage of 120 V. Further, machining data have been collected in real time and the behavior of machining time with work feed has been studied. In addition to it, a simple analytical model has been developed for calculating the erosion rate and it is seen that voltage produces more effect on erosion rate and machining time than the other parameters. Additionally, using the feed rate, capacitance and voltage at which minimum deviation took place, an array of 4 × 4, i.e., 16 micro-rods with 58 µm diameter and 830 µm length, has been fabricated on the bulk tungsten rod of 800 µm diameter.

High aspect ratio microtools find numerous applications in the production of miniaturized components and structures, e.g., drilling of microholes in ink jet nozzles, air bearings, and biomedical devices. The present study aims to machine microrods using reverse microelectrical discharge machining (R-μEDM) process. These microrods can be used as microtools for drilling microholes. A detailed experimental investigation has been carried out with the help of Taguchi's orthogonal array for understanding the mechanism of the process. The process parameters such as voltage, feed rate, and capacitance are considered to perceive their effect on response measures such as machining time, deviation in length, deviation in average diameter, standard deviation (SD) in diameter, and surface roughness. The optimal process parametric condition of R-μEDM has been determined for desired performance, i.e., obtaining the target length and average diameter of the microrod and ensuring its straightness with minimum time duratio...

Material selection is one of the most vital decisions in finest design of any manufacturing process and product. Proper material selection plays an elementary role for a productive manufacturing system with better product and process superiority along with cost optimization. Improper material selection often causes huge cost contribution and drives an organization towards unripe product failure. In this paper, multi-objective optimization on the basis of ratio analysis (MOORA) method is applied to solve magnesium alloy material selection problem to use in automotive wheel applications. A comprehensive list of all the prospective materials from the best to the worst is obtained, taking into account multi-conflicting material selection attributes. The ranking performance of the method is also compared with that of the past researchers. It is observed that the method is very simple to understand, easy to implement and provide almost exact rankings to the automotive wheel material alternative https://journalnx.com/

In 2005 the government of India declared its policy for development of biofuels. The Ministry of New and Renewable Energy Sources of India has identified around 400 oil seed species available in the forests of India, which can be used for various applications including that as biofuels. Due to lack of detailed studies and non-availability of mechanism for the collections of these oilseeds, this source has remained largely untapped. The National Oilseed and Vegetable Oil Development Board (NOVOD) is working on strategies to promote studies and for establishing mechanisms for collection. These biofuels can be effectively used to meet some or all of the energy needs of remote un-electrified villages. This can be achieved by generating electricity at village level, in a decentralized manner by using small capacity generator sets running on biodiesel derived from locally available oils. In this case it will be essential to find techniques for utilization of non-edible de-oiled seedcake obtained as the byproduct of this process. Using the seedcake for biogas generation by anaerobic digestion process is a promising option. Mahua ( Madhuca indica ) is a specie naturally available with high tree density in most parts of India. In addition one less familiar oil seed specie available in central India is Hingan ( Balanites aegyaptiaca ). The paper investigates the suitability of de-oiled cakes of these two oilseeds for biogas generation. This investigation reveals that both the seedcakes have a mean biogas generation potential in the range of 198 to 233 l/kg of seedcake. The biogas generated from these sources could make a significant contribution to cooking energy demand in rural areas. The paper also highlights the fact that the sludge and the slurry coming out of the reactor as waste have very high manurial value by virtue of its high nitrogen content and a good amount of other secondary and tertiary nutrients.

Aims: The aim of the study was to assess the safety and efficacy of Bivalirudin + Glycoprotein (Gp) IIb/IIIa inhibitor as compared to unfractionated Heparin (UFH) + Gp IIb/IIIa inhibitor in high risk patients undergoing elective percutaneous coronary intervention (PCI). The primary end point was time to sheath removal and ambulation where as peri-procedure myocardial damage, access site bleeding and major adverse cardiac events (MACE) rates were secondary end points. Methods: One hundred and one high risk patients undergoing elective PCI were randomly assigned to either Bivalirudin + GpIIb/IIIa inhibitor or UFH + Gp IIb/IIIa inhibitor. PCI was performed by standard technique and activated clotting time was monitored immediately on arrival to recovery area and every 60 min thereafter. Sheath were pulled out once ACT was below 150 seconds and patients were mobilized 6hrs after sheath were removed. Peri-procedure myocardial damage was assessed by serial Trop I levels. Results: Patient assigned to Bivalirudin + Tirofiban has significantly reduced time to sheath removal and ambulation as compared to those who received UFH + tirofiban (p < 0.0001) although peak Act did not differ in the groups. Peak Trop I levels were significantly lower in Bivalirudin + Tirofiban group (p = 0.023) and peri-procedure Trop I elevation occurred in significantly lower number of patients treated with Bivalirudin + Tirofiban (p = 0.029). Conclusions: The combination of Bivalirudin + Tirofiban was safe and effective as compared to UFH + Tirofiban in high risk patients undergoing elective PCI.

The use of biodiesel as a diesel fuel extender and lubricity improver is rapidly increasing. While most of the properties of biodiesel are comparable to petroleum based diesel fuel, improvement of its low temperature flow characteristic still remains one of the major challenges when using biodiesel as an alternative fuel for diesel engines. The biodiesel fuels derived from fats or oils with significant amounts of saturated fatty compounds will display higher cloud points and pour points. This paper is aimed to investigate the cold flow properties of 100% biodiesel fuel obtained from Madhuca indica, one of the important species in the Indian context. In this paper, the cold flow properties of biodiesel were evaluated with and without pour point depressants towards the objectives of identifying the pumping and injecting of these biodiesel in CI engines under cold climates. Effect of ethanol, kerosene and commercial additive on cold flow behavior of this biodiesel was studied. A considerable reduction in pour point has been noticed by using these cold flow improvers. The performance and emission with ethanol blended Mahua biodiesel fuel and ethanol–diesel blended Mahua biodiesel fuel have also been studied. A considerable reduction in emission was obtained. Ethanol blended biodiesel is totally a renewable, viable alternative fuel for improved cold flow behavior and better emission characteristics without affecting the engine performance.

Background: Asian Indians account for one-fifth of all cardiovascular deaths worldwide. It is well known that hypertension is a major risk factor for cardiovascular mortality and morbidity, but there has been no national survey for estimating the prevalence of hypertension in the Indian population. Hypertension in this ethnic group is less well studied than hypertension in blacks or Caucasians. Methods: We searched PubMed and MEDLINE using the words “Asian Indians” “hypertension” “blood pressure” “epidemiology” “prevalence” “prevention” “treatment” as search items and went through the major Indian journals to gather sufficient data regarding hypertension in Asian Indians. Most of the data was acquired from studies conducted in India, as there are only limited studies on Indians who have settled overseas. Results: High prevalence of hypertension was found in the urban Indian population as compared to the rural Indian population, while there was inconsistent data on migrant Indians. The modern Indian diet and lifestyle may be responsible for the urban - rural differences. Large proportion of Indian population is unaware of their condition and significant proportion of them is pre-hypertensive. No specific treatment guidelines for this ethnic group are available. Conclusion: The escalating incidence of hypertension among Asian Indians in urban India is alarming. This will likely add to the already existing cardiovascular disease burden in this ethnic group and it is imperative to conduct additional epidemiological and clinical studies to assess the prevalence, pathogenesis, and optimal pharmacotherapy of hypertension in Asian Indians. Aggressive screening and treatment regimen should be adopted considering the risk of untreated and sub-optimally treated hypertension and specific guidelines for treatment of hypertension in Asian Indians appears warranted.

Vascular malformations are difficult to treat because of poor results of treatment and recurrence of symptoms. Percutaneous and/or transluminal embolisation has refined the treatment of surface vascular lesions; especially with availability of variety of sclerosants.We report a case of a young girl with vascular malformation of right foot, which was treated with percutaneous sclerotherapy with sodium tetradecyl sulphate (STS). Result was excellent and so far the patient is free of her symptoms.

CORRECTIONS TO “THE NEIGHBOURHOOD NUMBER OF A GRAPH” [INDIAN J. PURE AND APPLIED MATH., 16 (1985), 126–132] BY E. SAMPATHKUMAR AND PRABHA S. NEERALAGI

Recently the reperfusion therapy in the form of Primary Percutaneous Coronary intervention (PPCI) has become the gold standard for the treatment of Acute Myocardial Infarction. In spite of rapid revascularization either with PPCI or thrombolytic therapy, the significant number of patients develops decreased left ventricular function leading to heart failure which can increase long-term mortality and morbidity. The number of strategies are being evolved and evaluated to reduce this post infarct heart failure. They are being developed at the level of optimizing the outcomes of PPCI, protection against the reperfusion injury, and novel therapies like cardiac repair and regeneration and sonothrombolysis. Thrombus aspiration using simple aspiration catheters during PPCI are getting established as a useful adjunct tool to reduce distal embolisation and consequently improving myocardial salvage. The newer antiplatelet drugs like Prasugrel and Ticagrelor may replace the Clopidogrel to reduce ischemic complications. The reduction in reperfusion injury using drugs has shown mixed results. The newer modalities like cardiac repair and regeneration using stem cell therapy looks promising but are yet to be established.

Granger CB, Alexander JH, McMurray JJ, ARISTOTLE Committees and Investigators. N Engl J Med 2011;365:981–92.

The Euro Heart Survey on diabetes and heart has demonstrated high prevalence of latent glucose abnormalities in non-diabetic patients with coronary artery disease (CAD) in the European population. The aim of our survey was to assess the prevalence of latent abnormal glucose regulation in adult non-diabetic CAD patients in India.Seven centers distributed across India recruited 350 patients. The diagnosis of CAD was done by coronary angiography showing50% stenosis in any major epicardial coronary artery or its branches. Oral glucose tolerance test (OGTT) and fasting glucose levels were used to characterize glucose metabolism. Venous plasma glucose was measured before (fasting) and 2 hours after ingestion of glucose. Impaired fasting glucose (IFG) was defined as OGTT (0 minute)or=100 mg/dl but126 mg/dl and OGTT (2 hours)140 mg/dl. Impaired glucose tolerance (IGT) was defined as OGTT (0 minute)126 mg/dl and OGTT (2 hours)or=140 mg/dl but200 mg/dl. Of the 350 patients studied, 176 (50.28%) had impaired glucose regulation (IFG-28 [8%]; IGT-148[42.28%]) and 75 (21.42%) had newly detected Diabetes. In all 251 (71.7%) patients with CAD had previously undetected abnormal glucose regulation.This survey demonstrates the presence of abnormal glucose regulation in almost three quarters of the non-diabetic Indian CAD patients. OGTT should be recommended as routine screening test for detecting latent glucose abnormalities in all CAD patients.

Diesel engine is a major source of power of the future but the major growing concern is the emissions of nitrogen oxides and diesel particulates. This work deals with the particulate emission control of diesel engine exhaust using ceramic filter. The selection of CFT with suitable size, geometry, cell density, wall thickness and microstructure becomes most important. In order to achieve required particulate matter emission limits and lower backpressure, optimization of porosity, pore size distribution, mean pore size and pore connectivity in CFT is crucial. CFT are developed and tested on the basis of porosity, diameter and length of CFT with necessary recommended trials. Further experiments were carried out to understand the effect of porosity, diameter and length of CFT on the back pressure, rate of back pressure rise, filtration efficiency and break power of diesel engine. The investigation of the research work provides adequate relevant information about the development of ceramic type ceramic filter trap (CFT) with naturally available material and effect of CFT on particulate matter concentration and on engine performance. Use of CFT reduced smoke drastically without increasing back pressure beyond tolerable back pressure limit. Performance of developed CFT was compared with established CFT and matches with it. Cost of developed CFT is the distinct advantage which will promote cottage industries in undeveloped nations, and provide rural employment.Copyright © 2009 by ASME

The gradual depletion of world petroleum reserves, increases in prices of petroleum based fuels and environmental pollution due to exhaust emissions have encouraged studies to search for alternative fuels. Biodiesel is an alternative diesel fuel consisting of alkyl monoesters of fatty acids derived from vegetable oils. It has been the focus of considerable amount of recent research because it is renewable and reduces the emission of some pollutants. The desirability of developing biodiesel from different tree borne oil seeds and decreasing the dependency on petroleum based fuels has been discussed by many over the last few decades. However some of the important issues like compatibility of biodiesel with the crankcase lubricating oil, thermal stability of lubricating oil with biodiesel usage, changes in physical and chemical properties of lubricating oil with biodiesel etc. have not been sufficiently investigated. This needs to be addressed in order to ensure the long term acceptability of biodiesel in an existing family of diesel engines. In the present work these issues have been addressed. For this purpose engine endurance tests were conducted on CI engines. Two new single cylinder four stroke CI engines were operated for 512 hours each for diesel and 100% biodiesel fuel. The endurance tests were conducted as per BIS 10000 part IX norms. Biodiesel from Jatropha oil was prepared in-house using transesterification process. The sample of lubricating oil was collected through a one way valve connected to the crankcase sump after every 128 hours intervals. Thermograviometric analysis (TGA) was used to evaluate the thermal stability of lubricating oil samples obtained from both the engines. The thermal decomposition of lubricating oil samples were measured as a function of various reaction parameters such as temperature, time and heating rates. This TGA test involves a weight change as the oil was heated. The weight loss data of the sample was logged using the in situ computer. Early decomposition of biodiesel fueled engine lubricating oil was observed as compared to diesel fueled engine lubricating oil. The changes in viscosity of lubricating oil were also monitored during the endurance test and discussed in detail. A higher level of crank case dilution was observed in case of biodiesel as compared to diesel.Copyright © 2009 by ASME

Diesel engine is the most efficient power plant among all known types of internal combustion engines. The Diesel engine is a major candidate to become the power plant of the future. Environmental benefits of Diesel such as low green house gas emissions are balanced by growing concern with emission of Nitrogen oxide (NOx) and Diesel Particulates (PM). The concern over Diesel particulate has increased in recent year because of health concerns. The objective of this research work is to identify the possibility of development of foam type diesel particulate filters (DPF) with indigenous ceramic materials which are easily available and cheaper. While developing the foam type diesel particulate filters, the main aim is to develop required porous structure for DPF with substantial strength, with low back pressure to minimize loss of engine performance, and with high trapping efficiency to reduce the particulate matter. The objective of this research work is also to investigate the effect of new developed filters without any regeneration arrangement and without any control or monitoring system, on the reduction of dry particulate matter and on the performance of diesel engine in terms of parameters like smoke density, back pressure, brake thermal efficiency and brake power. Use of DPF reduces smoke density with back pressure in acceptable limit. Parameters like brake power loss, increase in brake specific fuel consumption and decrease in brake thermal efficiency are caused by increased engine back pressure created by installation of the DPF system. This power penalty is within permissible limits, but can be further reduced by incorporating a regeneration system.Copyright © 2009 by ASME

The desirability of developing biodiesel from different tree born oil seeds and decreasing the dependency on petroleum based fuels has been discussed by many over the last few decades. However some of the important issues of biodiesel like lubricity, low temperature flow characteristic, material compatibility have not been sufficiently investigated. In this paper, an attempt has been made to explore the lubricity and cold flow properties of biodiesel separately based on the experimental results. These two properties though may not be related with each other but plays significant role towards the long term acceptability of biodiesel in an existing CI engine. For biodiesel, the lubricity parameter is important to evaluate in the context of recent advent of ultra low sulfur diesel fuel (

By supporting hydrogen as an alternative fuel to the conventional fuel i.e. gasoline, new era of renewable and carbon neutral energy resources can be introduced. Hence, development of hydrogen fuelled internal combustion engine for improved power density and less emission of NOx has become today’s need and researchers are continuously extending their efforts in the improvement of hydrogen fuelled internal combustion engine. In this work, three dimensional CFD simulations were performed using CFD code (AVL FIRE) for premixed combustion of hydrogen. The simplified 3D geometry of engine with single valve i.e. inlet valve was considered for the simulation. Various combustion models for spark ignition for hydrogen i.e. Eddy Breakup model, Turbulent Flame Speed Closure Combustion Model, Coherent Flame model, Probability Density Function model were tested and validated with available simulation results. Results obtained in simulation indicate that the properties of hydrogen i.e. high flame speed, wide flammability limit, and high ignition temperature are among the main influencing factors for hydrogen combustion being different than that of gasoline. Different parameters i.e. spark advance angle (TDC to 40° before TDC in the step of 5°), rotational speed (1200 to 3000 rpm in the step of 300 rpm), equivalence ratio (0.5 to 1.2 in the step of 0.1), and compression ratio (8, 9 and 10) were used to simulate the combustion of hydrogen in spark ignition engine and to investigate their effects on the engine performance, which is in terms of pressure distribution, temperature distribution, species mass fraction, reaction progress variable and rate of heat release for complete cycle. The results of power output for hydrogen were also compared with that of gasoline. It has been observed that power output for hydrogen is almost 12–15% less than that of gasoline.Copyright © 2008 by ASME

In this research, single pass cutting of HCHC (High Chromium High Carbon) die steel AISI D3 Grade has been used where material removal rate (MRR) and surface roughness (SR) are of primary importance. In general, achieving a high level cutting speed with a better surface finish is extremely difficult task because in wire cut electric discharge machining (WEDM), no particular parametric combination is expected to yield simultaneously in the best MRR and the best SR. Hence it can be considered as multi objective optimization problem. This research presents an attempt at multi objective optimization of the process parametric combinations by modeling the process using artificial neural network (ANN). A feed forward back propagation neural network based on matrix experimental design is developed to model the WEDM process. Based on the developed model, different response parameters are calculated for various input parameter setting. Finally they are compared to find out optimal combination of machining parameter setting. Electronica make EZEECUT PLUS model has been used for experimentation and a methodology has been suggested to determine the optimal combination of control parameters in WEDM. Research findings in the area of machining HCHC die steel through WEDM process will open up a new horizon and will certainly solve various challenging problems faced by the engineers and die makers in the field of modern manufacturing industry.Copyright © 2006 by ASME

Testing of catalytic converter with exhaust gas recirculation system for diesel engine to reduce pollute gases is chosen for present work. The emphasis is given on hydrocarbon (HC), carbon monoxide (CO) and oxides of nitrogen. The catalytic converter was developed with variations of catalyst plates. Perforated plates of copper and combination of copper oxide and cerium oxide (CeO2 +CuO) were used as the catalyst. Copper spacer was used in between plates to vary the distance. Secondary air was injected into the converter to aid oxidization of HC and CO. Experimental study was carried out on computerized kirloskar single cylinder four stroke (10 B.H.P, 7.4 KW) diesel engine test rig with an eddy current dynamometer. The converter was tested with various combination with exhaust gas re-circulation (EGR) system. There are some improvements in the reduction and conversion efficiency of HC & CO. Exhaust gas re-circulation has proved to be effective in reducing NOx.

Retarded injection is used to control NOx emissions. Exhaust Gas Recirculation (EGR) is also an effective means of reducing NOx emissions from compression ignition engines. Higher fuel injection pressure may improve the combustion. EGR can be combined advantageously with other emission reducing measure such as retarded injection timing and performance improvement measures such as higher fuel injection pressure to have a good effect. The methyl ester of jatropha oil, known as biodiesel, is receiving increasing attention as an alternative fuel for diesel engines. Biodiesel is a non-toxic, biodegradable and renewable fuel with the potential to reduce engine exhaust emissions. The jatropha oil methyl ester was obtained through transesterification process. Various properties of the biodiesel thus developed were evaluated and compared in relation to that of conventional diesel oil. In the present investigation neat jatropha oil methyl ester (JME) as well as the blends of varying proportions of JME and diesel were used to run a CI engine with standard conditions (No EGR, No Injection Retard and 20 MPa Fuel Injection Pressure) and with combination of 20 % EGR, 4° retarded injection timing and 30 MPa fuel injection pressure. The addition of jatropha oil methyl ester (JME) to diesel fuel has significantly reduced HC, CO and smoke emissions but it increases the NOx emissions slightly with standard conditions. The NOx emission was drastically decreased with modified conditions. Further the smoke and unburned hydrocarbon emissions were decreased with modified conditions as compared to standard conditions. The brake thermal efficiency was improved with modified conditions at various loads. Exhaust gas temperatures were similar. The maximum cylinder gas pressure and heat release rate were lowered.Copyright © 2006 by ASME

The present work deals with experimental studies on heat transfer characteristic for buoyancy induced flow through inclined tubes inserted with twisted strips. The parameters varied during the experimetation are; tube inclination, heat supply twist pitch and fluid inlet temperature. It was found that the percentage enhancement in heat transfer coefficient decreases with increase in pitch and tube inclination. The flow rate is found to decrease with decrease in the pitch and increase in the tube inclination. It was also observed that the heat transfer coefficient and flow rate decreases with the increase in the inlet fluid temperature. This may be due to reduction in Rayleigh number caused because of higher heat loss at the tube surface.

Testing of catalytic converter with exhaust gas recirculation system for diesel engine to reduce pollute gases is chosen for present work. The emphasis is given on hydrocarbon (HC), carbon monoxide (CO) and oxides of nitrogen. The catalytic converter was developed with variations of catalyst plates. Perforated plates of copper and combination of copper oxide and cerium oxide (CeO2 +CuO2) were used as the catalyst. Copper spacer is used in between plates to vary the distance. Secondary air was injected into the converter to aid oxidization of HC and CO. Experimental study was carried out on computerized kirloskar single cylinder four stroke (10 B.H.P, 7.4 KW) diesel engine test rig with an eddy current dynamometer. The converter was tested with various combination of the exhaust gas re-circulation (EGR) system. There are some improvements in the reduction and conversion efficiency of HC & CO. Exhaust gas recirculation has proved to be effective in reducing NOx.

With the fossil fuel depleting very fast, researchers have concentrated on developing new agro-based alternative fuels, which will provide sustainable solution to the energy crisis. Presently, bio-diesels, which are obtained from trans-esterification of straight vegetable oil (SVO), are being used along with diesel in blends. The transesterification process, which is a costly, time consuming and oil quality dependent process is eliminated in the present study. The straight vegetable oils, namely, Jatropha and Pongamia have been analyzed in details. The trial was conducted on a 4-stroke, single cylinder diesel engine, having compression ratio 17.5:1. The experiments were carried out for fuel consumption and emission levels at various loads and without any engine modifications. The results obtained were comparable to and better than diesel. The CO and NOx emission was found less for Jatropha as well as for Pongamia. The specific fuel consumption (SFC) was found to be low for both Jatropha and Pongamia oil at moderate loads. The brake thermal efficiency was also found to be better for both Jatropha and Pongamia oil as compared to diesel

Testing of catalytic converter with exhaust gas re-circulation system for diesel engine to reduce pollute gases is chosen for present work. The emphasis is given on hydrocarbon (HC), carbon monoxide (CO) and oxides of nitrogen. The catalytic converter was developed with variations of catalyst plates. Perforated plates of copper and combination of copper oxide and cerium oxide (CeO2 +CuO) were used as the catalyst. Copper spacer was used in between plates to vary the distance. Secondary air was injected into the converter to aid oxidization of HC and CO. Experimental study was carried out on computerized kirloskar single cylinder four stroke (10 B.H.P, 7.4 KW) diesel engine test rig with an eddy current dynamometer. The converter was tested with various combination with exhaust gas re-circulation (EGR) system. There are some improvements in the reduction and conversion efficiency of HC & CO. Exhaust gas re-circulation has proved to be effective in reducing NOx .Copyright © 2005 by ASME

Biodiesel is a non-toxic, biodegradable and renewable fuel with the potential to reduce engine exhaust emissions. The methyl ester of jatropha oil, known as biodiesel, is receiving increasing attention as an alternative fuel for diesel engines. The biodiesel is obtained through transesterification process. Various properties of the biodiesel thus developed are evaluated and compared in relation to that of conventional diesel oil. In the present investigation neat jatropha oil methyl ester (JME) as well as the blends of varying proportions of jatropha oil methyl ester (JME) and diesel were used to run a CI engine. A four stroke diesel engine having compression ratio of 17.5: 1 and developing 5.2 kW at 1500 rpm was used. Experiments were initially carried out on the engine at all loads using diesel to provide baseline data. Significant improvements in engine performance and emission characteristics were observed for JME fuel. The addition of jatropha methyl ester (JME) to diesel fuel has significantly reduced HC, CO, CO2 and smoke emissions but it increases the NOx emission slightly. The maximum reduction in smoke emission was observed by 35% in case of neat biodiesel operation as compared to diesel. The unburned hydrocarbon emission was drastically reduced by 53% for neat biodiesel operation.

The growing environmental concern and increasing petroleum crisis have led many to look for more cleaner, efficient and cost effective alternative transportation fuels. This paper deals with an experimental investigation on performance and emission characteristics of a S I engine using petrol and LPG. Several tests have been conducted with different loading and speed with gasoline and LPG as fuels and engine performance parameters like brake thermal efficiency, volumetric efficiency, brake specific fuel consumption along with cost analysis were studied. The relative variation of these parameters has been focused in the present paper. The objective of the present study was to test the suitability of LPG as a fuel for low compression ratio S I engines used in light duty vehicles with the minimum possible modifications to be introduced in the engine. The engine running with LPG exhibits significantly lower level of exhaust emissions and cost effectiveness however there is reduction in the thermal efficiency relative to the engine run on gasoline. The significant reduction in the HC and CO emissions (65% and 50% respectively) is observed in the test programme.Copyright © 2005 by ASME

Research Division, Laxmi Pest and Fumigation Pvt. Ltd., 3 Khatipura, Indore-452 007, India School of Mathematics, Devi Ahilya Vishwavidyalaya, Indore-452 001, India Department of Chemistry, A. P. S. University, Rewa-486 003, India Manuscript received 29 November 1999. revised 27 April 2000, accepted 8 June 2000 Szeged index (Sz) is a new topological index based on distances between vertices of a graph. It is the extension of Wiener index (W) on cyclic graphs. These indices of cyclic molecules differ, in the general case, Sz exceeds W. Otherwise, the relation between Sz and W of cyclic molecules is not yet established thoroughly. In order to get some information about this relations, we have examined monocyclic molecules consisting n vertices (n = even, > or = 4) and observed that Sz = 2 W.

We aimed to identify periprocedural quantitative coronary angiographic (QCA) variables that have predictive value on long-term angiographic results and to construct multivariate models using these variables for postprocedural prognosis.Coronary stent implantation has reduced the restenosis rate significantly as compared with balloon angioplasty in short de novo lesions in coronary arteries3 mm in size. Although the postprocedural minimal luminal diameter (MLD) is known to have significant bearing on long-term angiographic results, no practically useful model exists for prediction of angiographic outcome based on the periprocedural QCA variables.The QCA data from patients who underwent Palmaz-Schatz stent implantation for short (15 mm) de novo lesions in coronary arteries3 mm and completed six months of angiographic follow-up in the four prospective clinical trials (BENESTENT I, BENESTENT II pilot, BENESTENT II and MUSIC) were pooled. Multiple models were constructed using multivariate analysis. The Hosmer-Lemeshow goodness-of-fit test was used to identify the model of best fit, and this model was used to construct a reference chart for prediction of angiographic outcome on the basis of periprocedural QCA variables.Univariate analysis performed using QCA variables revealed that vessel size, MLD before and after the procedure, reference area before and after the procedure, minimal luminal cross-sectional area before and after the procedure, diameter stenosis after the procedure, area of plaque after the procedure and area stenosis after the procedure were significant predictors of angiographic outcome. Using multivariate analysis, the Hosmer-Lemeshow goodness-of-fit test showed that the model containing percent diameter stenosis after the procedure and vessel size best fit the data. A reference chart was then developed to calculate the expected restenosis rate.Restenosis rate after stent implantation for short lesions can be predicted using the variables percent diameter stenosis after the procedure and vessel size. This meta-analysis indicates that the concept of "the bigger the better" holds true for coronary stent implantation. Applicability of the model beyond short lesions should be tested.

Background Optimal inhibition of platelet aggregation (IPA) may afford greater protection against ischemic events during percutaneous coronary intervention (PCI). The objective of this study was to test several antiplatelet regimens in elective high-risk PCI patients by comparing different combinations of glycoprotein IIb/IIIa inhibitors and clopidogrel. Methods The study was a randomized open-label study at 3 heart centers in India. One hundred twenty patients were enrolled between July 2006 and September 2006. Patients were randomized to 1 of the 4 groups: group A—tirofiban, group B—eptifibatide, group C—tirofiban + clopidogrel 600-mg loading dose, and group D—eptifibatide + clopidogrel 600-mg loading dose. All patients received a clopidogrel maintenance dose after PCI. The primary outcome measure was the IPA assessed at 10 minutes, at 6 to 8 hours, and at 24 hours. Results The IPA was higher with high-dose tirofiban compared with eptifibatide at 10 minutes (95.88 ± 5.85% vs 91.22 ± 7.52%, P = .003) and at 6 to 8 hours (93.11 ± 7.6% vs 85.45 ± 11.03, P 95% IPA with the high-dose tirofiban regimen. Conclusions This head-to-head study comparing high-dose tirofiban with double-bolus eptifibatide demonstrated higher degree of platelet inhibition with high-dose tirofiban at 10 minutes and at 6 to 8 hours in patients undergoing elective high-risk PCI. The addition of clopidogrel did not acutely extend the IPA from intravenous glycoprotein IIb/IIIa inhibitors, but did so at 24 hours.

The deformation of an elastic layer bonded to a rigid half-space and subjected to bands of pressure spaced periodically along a strip is treated. It is shown that there exists a critical periodicity of the band spacing for which the displacement of the top surface, midway between the bands, is a maximum. It is concluded that this periodicity varies with the thickness of the slab, the Poisson's ratio of the material, and the band width. Numerical calculations are presented to show the effect of these parameters.

Background Drug eluting stents have remarkably improved results of percutaneous coronary angioplasty. Most of the currently available drug eluting stents uses a durable polymer as drug carrier which has been implicated in local inflammatory response and continued incidence of late and very late stent thrombosis. The Pronova XR stent is one from those new generation polymer free sirolimus eluting stents in which pharmaceutical excipient is used for the timed release of sirolimus from the XR stent platform instead of a polymeric coating. Methodology We consecutively recruited 121 patients undergoing elective or urgent PCI at our center. All the patients were followed up clinically and mandatory follow up angiogram at 6 months was done for one third of the total patients. An independent core lab analyzed paired angiograms. Results The primary efficacy endpoint was death, MI, TVR at 6 months which occurred in 6.66% patients. The QCA analysis showed reference vessel diameter of 2.5 + 0.44 mm at baseline and the minimal luminal diameter was 0.88 + 0.43 mm giving baseline diameter stenosis of 65.26 + 15.89%. The immediate post procedure in-segment diameter stenosis assessed was 23.68 + 8.96% which increased to 36.02 + 24.48% at follow up with a late lumen loss of 0.25 + 0.76 mm at mean of 191 days. Conclusion Coronary angioplasty with polymer free Pronova XR stents results in acceptable late lumen loss and very low target lesion revascularisation at short and intermediate term in unselected patients.

Department of Chemistry, University of Poona, Poona-411 007 Manuscript received 15 November 1975, revised 20 Jury 1976, accepted 10 November 1976 Barium-2,3,4-trihydroxyacetophenone system in an aqueous medium showed a broad absorp­tion maximum at 560 nm (\(\varepsilon\) 560 = 1.27 x 103 litres/mole-cm). It has a violet-green colour. The optimum conditions for the spectrophotometric determination are : pH range 11.8-12.4; concen­tration range of barium 22–75 ppm for a 10 ml of 8 x 10-3M reagent in a total volume of 25 ml; absorbance measurements must be made within the interval of 15 to 60 minutes. Beer's law is obeyed at 560 nm for the concentration range of 45-130 ppm of barium (1-cm cell). An error of +2% at a barium concentration of 60 ppm was observed for vanadate, chromate, manganese(II) and uranyl (4 ppm) ions. The presence of calcium, strontium and iron(III) causes an appreciable error; magnesium (20 ppm) completely coprecipitates barium