Effect of Firing Temperature and time on swelling behavior of reduced iron ore pellets

The increasing trend in the prices of steel scrap and its short supply led the steel technologists to find a suitable charge mix in the form of sponge iron or Direct Reduced Iron (DRI). Sponge Iron or DRI is obtained from the direct reduction of iron ore and has iron content between 84 to 95 percent. Technically and technologically, sponge iron has been found to be a suitable material for charging in blast furnaces. In the existing blast furnace an increase in production by at least 25 to 35% can be achieved by using pre reduced iron ore. Sponge iron is a better substitute for scrap for steelmaking through EAF / IF routes due to its homogenous nature, Improved productivity and lower coke consumption. Also majority of fines which are generated during the course of handling, mining, transportation etc are exported at a through away price which need to be utilized by making iron ore pellets for sponge iron making. According to industry experts, the preference for usage of DRI will lead to the use of 80 percent DRI in the charge mix in EAFs by 2009-10 which may even reach the 85 percent level by 2011-12 in the various regions of India. A lot of investigations have been carried out on direct reduction process of iron oxides by carbonaceous materials, but little work has been done on the characterization of properties and reduction behavior of iron ore of some mines of Orissa. In the present project work, an attempt has been made to study the reduction behavior and kinetics of fired iron ore pellets. The effect of firing temperarure (1000, 1100 and 1300oC), binder (concentrated sugar cane juice) on strength of pellets and the effect of different reduction parameters such as temperature (850-1000°C), time (0-90min.), reductant quality, mixing of particles of different sizes at different ratios for pellet preparation etc. on the reduction, swelling behavior of iron ore pellets. These form the subject matter of the thesis. First chapter gives the introduction about the subject. It speaks about the need of DRI industry, scope, present status and future planning of DRI industry in India, world wise DRI production, etc. The second chapter deals with the literature survey. The third chapter deals with selection of raw materials, preparation of samples, preparation of iron ore pellets, experimental procedure. Results and discussions are out lined in fourth chapter. Lastly, these conclusions have been followed by the suggestion for future work and list of references

Study On Effect of Boron Carbide, Aluminium Oxide and Graphite On Dry Sliding Wear Behaviour of Aluminium Based Metal Matrix Composite at Different Temperature

The present research has been conducted to study the impact of boron carbide (B4C), aluminium oxide(Al2O3) and graphite on Aluminium 2219 (Al2219). According to current research, B4C and graphite material be a good substitute for Al2219.Reinforced composites and unreinforced Al2219 prepared by a stir casting process. A scanning electron microscope was used to analyze the reinforcement and distribution in the matrix and worn surface of the specimen. Exceptional wear resistance (30%) exhibited by  B4C and graphite-reinforced hybrid composite at 150 ºC in contrast with the unreinforced Al2219. The B4C and Gr reinforcement particulate existence improves the strengthening kinetics in the matrix phase at 150 °C. The artificial neural network used to get the test significance, normalized factor importance and absolute relative error of less than 1%

Enhanced Critical parameters of nano-Carbon doped MgB2 Superconductor

The high field magnetization and magneto transport measurements are carried out to determine the critical superconducting parameters of MgB2-xCx system. The synthesized samples are pure phase and the lattice parameters evaluation is carried out using the Rietveld refinement. The R-T(H) measurements are done up to a field of 140 kOe. The upper critical field values, Hc2 are obtained from this data based upon the criterion of 90% of normal resistivity i.e. Hc2=H at which Rho=90%Rho; where RhoN is the normal resistivity i.e., resistivity at about 40 K in our case. The Werthamer-Helfand-Hohenberg (WHH) prediction of Hc(0) underestimates the critical field value even below than the field up to which measurement is carried out. After this the model, the Ginzburg Landau theory (GL equation) is applied to the R-T(H) data which not only calculates the Hc2(0) value but also determines the dependence of Hc2 on temperature in the low temperature high field region. The estimated Hc(0)=157.2 kOe for pure MgB2 is profoundly enhanced to 297.5 kOe for the x=0.15 sample in MgB2-xCx series. Magnetization measurements are done up to 120 kOe at different temperatures and the other parameters like irreversibility field, Hirr and critical current density Jc(H) are also calculated. The nano carbon doping results in substantial enhancement of critical parameters like Hc2, Hirr and Jc(H) in comparison to the pure MgB2 sample.Comment: 25 pages with 9 Figs: comments/suggestions([email protected]

Postoperative morbidity following Whipple’s procedure for periampullary carcinoma: a retrospective study spanning 5 years

Background: The morbidity rates for Whipple’s procedure has remained high even as mortality rates were coming down. This study was intended to assess postoperative morbidity rates in  a tertiary care centre and to compare it with other centres.Methods: Data was collected from various registers and medical records for this retrospective cohort study. All Whipple’s procedures for 5 years were included in the study. Statistical analysis was done using R statistical software and the results were tabulated.Results: There were 48 patients and half of them developed morbidity. Surgical site infection was the most common complication (18.8%) followed by pulmonary complications (12.5%) and bile leak (6.25%). Half of the patients having pulmonary complications died while nobody with surgical site infection or bile leak died.Conclusions: In this study the morbidity rates were comparable to other centres. Hypoalbuminemia is a significant predictor of morbidity. Surgical site infection was the most common morbidity. Pulmonary complications were the most common cause for death. Morbidity rate is comparable to other centres and Whipple’s procedure is a safe surgery in the tertiary centre where the study was conducted

Security with Evidence Using Zigbee

The ZigBee standard is designed to enable the deployment of low-cost, low-power and self-forming wireless sensor and control networks based on the IEEE 802.15.4 physical radio standard. Despite the low data rates of ZigBee, its use for transmission of image has been proven to be feasible. The current researches of ZigBee wireless sensor network on industrial automation, electronic products, smart buildings and medical care were presented and, as an explorative application of ZigBee wireless sensor network in providing security using motion sensor and image capturing device is appreciable. This paper presents the idea of providing security with evidence in the frame work of ZigBee-cam project which targeted the development of a low-cost, ultra-low-power, long-range, ergonomic wireless cam using ZigBee technology to transmit high quality image. Keywords : ZigBee Cam, ZigBee Coordinator, ZigBee Massage, ZigBee IP gatewa

Laser induced rotation of trapped chiral and achiral nematic droplets

We study the response of optically trapped achiral and chiralised nematic liquid crystal droplets to linear as well as circular polarised light. We find that there is internal dissipation in rotating achiral nematic droplets trapped in glycerine. We also demonstrate that some chiralised droplets rotate under linearly polarised light. The best fit to our data on chiralised droplets indicates that rotational frequency of these droplets with radius R is approximately proportional to1/R^2, rather than to 1/R^3.Comment: 15 pages, 6 figure

Concept of Grip Assistive Braking on Four Wheelers

Braking systems in all the segments of vehicles seems to be one of the most crucial developing systems. Many research and developments are carried out in terms of braking of a vehicle in order to enhance the braking efficiency and reduction in stopping distance. This article depicts the concept of assistive braking on four wheelers where we elaborately describe the Braking distance, Thinking distance and Stopping distance after which our concept of braking is proposed with all the technical aspects along with the various components and its efficiency in our real time use. This research article mainly focuses on technical aspects that aim to reduce the reaction time and reflex actions of the driver which in turn is used as a factor to reduce the stopping distance of the vehicle. Various types of biological reactions by a human are observed and then a particular muscular reaction is chosen as a source of intimation for our braking system. When an object is spotted by the driver, the reflex action takes place via a receptor, sensory neurons, spinal cord and from where the muscular reaction takes place. A unique steering with an array of grip sensors is designed and incorporated also with various functions of the vehicle but for this instance, we mainly focus on braking assistance of the vehicle. Thus the unique steering wheel plays the role of connection between vehicle and the driver

An Experimental Study On Load Carrying Capacity Of A Magnetic Bearing

The use of bearing is essential to all types of machines they provide the function of supporting heavier component in a desired position. These bearings have contact with the rotating part and causes surface wear which can be controlled by lubrication. The standards of performance for rotating equipment can be raised by providing robust, cost effective and easy to implement lsquoMagnetic bearingsrsquo. A radial magnetic bearing, consisting of two permanent magnets, is an attractive choice because of its zero wear, negligible friction, and low cost, but it suffers from low load capacity, low radial stiffness, lack of damping and high axial instability. To enhance the radial load and radial stiffness and reduce the axial thrust, a theoretical and experimental study of various radial configurations, including hydrodynamic lubrication to improve dynamic performance of the magnetic bearing is made