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Slurry spray technique (SST) is a distinctive variant among the numerous and already established coating techniques. Functionally graded thermal barrier and environmental barrier coating have been the functionalities developed so far for the process. Among the choice of the various ceramic feedstocks available mullite and partially stabilized zircona have been found suitable and investigated for the coating deposition via SST. This chapter reports the findings of the corrosion studies in simulated industrial corrosive environments and characterization results of the six sets of slurry sprayed mulite-nickel based coatings. Decent protection against coating has been found during the immersion test performed on these coatings for evaluating their corrosion performance. The developed coatings are recommended for use in applications to endure the elevated temperature and inflict corrosion. Thermal cycling test was performed to support the acceptable thermal shock resistance and coating compliance of the developed coatings.

Mullite-nickel-based coatings were deposited on low carbon steel by a relatively simple and low-cost surface deposition technique based on the slurry spray technique (SST) developed for environmental barrier coating applications. This paper reports the findings of an experimental investigation into the effects of SST process parameters in developing functionally graded mullite-nickel-based coating with adequate adhesion strength, analyzing the effect of TiO2 as liquid-phase sintering additive. The present study outlines the use of Taguchi’s experimental design based on L8 orthogonal array used to accommodate the factors selected as well as their interaction effects for performance optimization. Four key SST process parameters used for the study namely, sintering temperature, sintering time, percentage of additives, and stamping pressure have been optimized for the chosen response characteristic of adhesion strength. The significant effect of confounding variables in the prospective interactions has been investigated. Analytical results suggested that the factor sintering temperature has prominent effect on adhesion strength. It has also been found that the factor sintering temperature and sintering time have the most significant lower order interaction effect in the selected range of parameters. The developed coatings using SST demonstrate dense coating deposits with a satisfactory adhesion strength which is comparable with that produced from traditional techniques.

Metallurgical joining of high thermal conductivity materials like aluminum has been technically challenging. This paper illustrates a novel method for joining of bulk metallic materials through microwave heating. Joining of aluminum alloy in bulk form has been carried out using microwave energy in a multimode applicator at 2.45 GHz and 900 W. SiC was used at both top and bottom of the workpiece as susceptor material to facilitate microwave hybrid heating (MHH). Aluminum in plate forms have been successfully joined through microwave heating within 600 s of exposure time. A sandwich layer of aluminum powder with approximately 0.5 mm thickness was introduced between the two candidate surfaces. Near complete melting of the powder particles in the sandwich layer does take place during the microwave exposure leading to metallurgical bonding of the bulk surfaces. Characterisation of the joints has been carried out through microstructure study, elemental analysis, phase analysis, microhardness survey, X-ray diffraction (XRD) pattern indicates that some aluminum powder particles got transformed into aluminum oxides. A dense uniform microstructure with good metallurgical bonds between the sandwich layer and the interface was obtained. The hardness of the joint area was observed to be 72.4 ± 10 Hv.

Bauxite residue is the waste generated during alumina production by Bayer’s process. The amount of bauxite residue (40–50 wt%) generated depends on the quality of bauxite ore used for the processing. High alkalinity and high caustic content in bauxite residue causes environmental risk for fertile soil and ground water contamination. The caustic (NaOH) content in bauxite residue leads to human health risks, like dermal problems and irritation to eyes. Moreover, disposal of bauxite residue requires a large area; such problems can only be minimised by utilising bauxite residue effectively. For two decades, bauxite residue has been used as a binder in cement industries and filler/reinforcement for composite materials in the automobile industry. Valuable metals and oxides, like alumina (Al2O3), titanium oxide (TiO2) and iron oxide Fe2O3, were extracted from bauxite residue to reduce waste. Bauxite residue was utilised in construction and structure industries to make geopolymers. It was also used in the making of glass-ceramics and a coating material. Recently bauxite residue has been utilised to extract rare earth elements like scandium (Sc), yttrium (Y), lanthanum (La), cerium (Ce), neodymium (Nd) and dysprosium (Dy). In this review article, the mineralogical characteristics of bauxite residue are summarised and current progresses on utilisation of bauxite residue in different fields of science and engineering are presented in detail.

In the present paper, we propose a secured scheme of digital signature connecting both conjugacy problem and discrete logarithm problem based on non-commutative group generated over a finite field. For this, we define a non-commutative group over matrices with the elements of finite field such that conjugacy and discrete logarithm problems can be executed together proficiently. By doing so, we can formulate the signature structures using conjugacy and discrete logarithm through non commutative group. In some domains, the above combination reduces to completely in discrete logarithm problem. This digital signature scheme more elemental over F* q(x) = G Ln (Fq). Here the security of the signature protocol depending on complexity of the problems associated with conjugacy and discrete logarithm. The security analysis and intermission of proposed protocol of digital signature is presented with the aid of order of complexity, existential forgery and signature repudiation.

Novel differentiator design technique is discussed by means of comparison of transfer function of differentiator define and develop in the Digital signal Processing (DSP) with the transfer function develop by cascade connection of transmission-lines configuration. Z-parameter is then used to define the scattering characteristics of equal electrical length transmission line. Finally, Cascade configuration of transmission-lines will develop second order differentiator and verified it by simulation result. Simulation result validates the mathematical observation obtained.

Ceramic-metal functionally graded materials (FGMs) have been attracting a great deal of attention as environmental barrier coatings (EBCs) for aerospace structures and turbine blades working under elevated temperatures and chemically harsh environment. A relatively new, simple and low cost manufacturing method of environmental barrier coatings based on the slurry spray technique (SST) has been developed. In this research, it is desired to develop this technique to achieve the coating quality comparable to the existing manufacturing methods, which are often expensive. This paper describes the development and optimization of mullite-nickel based coating using Slurry Spray Technique analysing the effect of MgO as liquid phase sintering (LPS) additive. Taguchi's experimental design based on L9 orthogonal array was employed for optimizing the tech- nique and analyzing the effect of selected process parameters (sintering temperature, sintering time and percentage of additives). The response parameter of the coating so produced is measured in terms of coating interface adhesion strength. The test results have been used to downselect the significant process parameters and help demonstrate the feasibility of coatings produced by slurry spray technique. The test results demonstrate satisfactory adhesion strength of the developed coating, which is comparable with that pro- duced from traditional techniques such as flame spray method.

In this paper, turning experiments on hardened steel were carried out with three kinds of cylindrical workpiece surfaces – continuous, interrupted, and fully interrupted – using coated carbide and cubic boron nitride (CBN) tools. The objective of this work was to investigate the conditions under which coated carbide tools give optimum results in terms of both tool life and surface integrity of the machined surface in comparison to costly CBN tools. The turning performance was evaluated in terms of maximum flank wear of the inserts and issues related to surface integrity like white layer formation, microhardness variation, residual stress generated, and surface roughness of the machined surface. The results indicated that the longest tool life was achieved with CBN tools, but the accumulated machining time of all the four cutting edges in coated carbide tools was comparable to that of CBN. The surface integrity achieved with carbide tools was also comparable to that achieved with CBN. The performance of carbide tools deteriorated at higher cutting speeds. The surface roughness value with all inserts under all cutting conditions was below 1.6 µm. The thickness of the white layer only varied from 0.4 to 1 µm, and no white layer was observed with interrupted and fully interrupted surfaces. Compressive residual stress was observed on the machined surface with a selected tool life criterion.

The past century has witnessed significant advancements in turning process, cutting tools, machine controls and coolant/lubricant chemistry. These developments have particularly enhanced the machining of difficult-to-cut materials, which are used for aerospace, steam turbine, bearing industry, nuclear and automotive applications. In turning operation, friction and heat generation at the cutting zone are the frequent problems, which affect the tool life and surface finish apart from other machining results. This mechanism of heat generation plays quite a negative role during the turning of modern materials due to their peculiar characteristics such as poor thermal conductivity, high strength at elevated temperature, resistance to wear and chemical degradation. A good understanding of the methods of lubrication/cooling at the cutting zone, reduction of heat generation will lead to efficient and economic machining of these modern materials. This paper presents an overview of major advances in techniques as minimum quantity lubrication (MQL)/near dry machining (NDM), high pressure coolant (HPC), cryogenic cooling, compressed air cooling and use of solid lubricants/coolants. These techniques have resulted in reduction in friction and heat at the cutting zone, hence improved productivity of the process. A brief survey of modeling/FEA techniques is also performed.

Increasing productivity and reducing manufacturing cost have always been keys to successful business. In machining, higher values of cutting parameters offer opportunities for increasing productivity, but this also involves greater risk of deterioration in surface quality and tool life. During the past decade significant advances have been made in the development of cutting tool materials for machining of ‘difficult-to-cut’ materials. The cost involved in the production of new turning tools is very high. To overcome this cost factor researchers have tried to bring about modifications in the turning process using existing tool materials. A good understanding of the cutting conditions, temperature generation, failure modes, and cutting forces leads to efficient control of the turning process. The literature reveals that modifications in the tool geometry (such as grooved/restricted contact tools (RCTs) and chamfered/honed edges), applications of cooling techniques, ultrasonic assisted turning (UAT), hot machining, and cryogenic treatment of inserts have led to efficient and economic machining of modern materials used for aerospace, steam turbine, bearing industry, nuclear, and automotive applications. This paper presents a review of the different techniques involved in turning which can supplement the performance of cutting tools for improved economics, good surface finish, and surface integrity during machining of the latest materials.

Golden Jackal (Canis aurius indicus) survives in a wide range of environment. Its foraging adaptation varies according to quality and abundance of food sources. The food habits also fluctuate according to season and habitat. This study investigated the diet composition of Golden Jackal using scat analysis method collected between November 2012 and April 2013 from Patna Bird Sanctuary (PBS), Uttar Pradesh, India. A total of 83 scats of Golden Jackal were collected and analysed. Sixteen food items were identified in Golden Jackal scats. Birds contributed maximum (ca. 38.92%) in Golden Jackal diet followed by rodents (ca. 12.14%), insects (ca. 8.92%), reptile (ca. 8.57%), vegetative matter (ca. 13.56%), rufous-tailed hare (ca. 6.07%), cattle (ca. 2.5%), squirrel (ca.1.42%), nilgai (ca.1.07%) and common palm civet (ca. 0.71 %). However (ca. 6.07 %) of prey items could not identified in Golden Jackal scats. Out of (ca. 38.92%) in bird’s contribution egret alone contributed about (ca.20.35%) in Golden Jackal diet followed by gargeny (ca. 8.93%), greater caucal (ca. 5.71%), babbler (ca.1.07%) and (ca. 2.85%) remains of birds were could not identified as per species level. This study is conducted to find out food habits of Golden Jackal and its impact on bird community structure.

The security and stability in a power system is governed by mainly two parameters frequency and voltage. The stable operation of power system depends mainly on the balance between active power and reactive power consumption and its respective generation. Nowadays, the operation of power system is kept near to its maximum stress level for maximizing the profits of the operating bodies. More priority is given to the active power market at cost of overlooking reactive power balance. This paper presents the need for emphasis on reactive power balance and adverse effect of MVar loading stress on synchronous generator. The ageing phenomenology is linked with stressed operation of the synchronous machine in order to highlight the inevitable need for reactive power management. Six bus test network is considered here for the case study.

Microalgae are sunlight-driven miniature factories that convert atmospheric CO2 to polar and neutral lipids which after esterification can be utilized as an alternative source of petroleum. Further, other metabolic products such as bioethanol and biohydrogen produced by algal cells are also being considered for the same purpose. Microaglae are more efficient than the conventional oleaginous plants in capturing solar energy as they have simpler cellular organization and high capacity to produce lipids even under nutritionally challenged and high salt concentrations. Commercially, microalgae are cultivated either in open pond systems or in closed photobioreactors. The photobioreactor systems including tubular bioreactors, plate reactors and bubble column reactors have their own advantages as they provide sterile conditions for growing algal biomass. Besides, other culture conditions such as light intensity, CO2 concentration, nutritional balance, etc, in closed reactors remain controlled. On the other hand, though the open ponds provide a cost-effective option to utilize natural light facility for algal cells, the tough maintenance of optimal and stable growth conditions makes it difficult to manage the economy of the process. Further, these systems are much more susceptible to contamination with unwanted microalgae and fungi, bacteria and protozoa that feed on algae. Recently, some work has been done to improve lipid production from algal biomass by implementing in silico and in vitro biochemical, genetic and metabolic engineering approaches. This article represents a comprehensive discussion about the potential of microalgae for the production of valuable lipid compounds that can be further used for biodiesel production.

Adult male rats received daily injections (sc) of estradiol-17 beta (50 microg/100 g body wt per day) for 7 days. When they were sacrificed 14 days after the last injection, serum levels of gonadotropins and testosterone and weights of accessory sex organs were decreased significantly, testicular 17-hydroxysteroid dehydroganase activity was suppressed and spermatogenesis was inhibited in 5.0% casein-fed estrogen-treated rats. Feeding of 20.0% casein diet to estrogen-treated rats resulted in increased serum concentration of gonadotropins and testosterone. LH and testosterone appeared to be normal in 20.0% casein-fed estrogen-treated rats while serum FSH levels remained subnormal. The estrogen-treated rats fed on 20.0% casein diet showed decreased spermatogenesis in comparison with control rats fed on 20.0% casein diet. Together, these results indicate that high casein diet stimulates synthesis of testicular testosterone and increases serum LH levels more than FSH in estrogen-treated rats. It is concluded that estrogen in the presence of high milk protein diet may be considered to be a suitable steroid hormone in the development of a male contraceptive.

To investigate the effect of arsenic on spermatogenesis.Mature (4 months old) Wistar rats were intraperitoneally administered sodium arsenite at doses of 4, 5 or 6 mg.kg(-1).day(-1) for 26 days. Different varieties of germ cells at stage VII seminiferous epithelium cycle, namely, type A spermatogonia (ASg), preleptotene spermatocytes (pLSc), midpachytene spermatocytes (mPSc) and step 7 spermatids (7Sd) were quantitatively evaluated, along with radioimmunoassay of plasma follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone and assessment of the epididymal sperm count.In the 5 and 6 mg/kg groups, there were significant dose-dependent decreases in the accessory sex organ weights, epididymal sperm count and plasma concentrations of LH, FSH and testosterone with massive degeneration of all the germ cells at stage VII. The changes were insignificant in the 4 mg/kg group.Arsenite has a suppressive influence on spermatogenesis and gonadotrophin and testosterone release in rats.

This paper introduces TimeCube-a technology product specifically designed for the analysis of master type data or dimensional data (such as customer information) which changes (in an aperiodic manner) over time. The application of time tested technology to original concepts from “unit of information and its three dimensionality”, Y. Ishii, 1982.2 [1] and “Three Dimensional DBMS (3D-DBMS)”, Y. Ishii, 1989.1.19 [2], has resulted in the development of TimeCube. TimeCube answers the increasing need in the IT marketplace for the efficient analysis of this distinct type of data. The focus is on analysis related to regenerating the data records at a previous instant of time, tracking the number and types of changes in the attributes for a record and examining the duration of particular states for the record. Beta testing is currently planned and/or already underway on various large customer sites in US, Japan and Australia for the future implementation of TimeCube.

Received 5 May 2009, in revised form 6 August 2009 Abstract. A granular flux, which is used in submerged arc welding, plays an important role in deciding the weld metal quality and it may cost up to half of the total welding consumable cost. A significant percentage of the flux gets converted into very fine particles, termed as flux dust, due to transportation and handling. Welding defects like porosity occur if welding is performed without removing these very fine particles from the flux, and if these fine particles are removed by sieving, the cost of welding will be increased significantly . Also if this flux dust is dumped, it creates pollution. The present study has been conducted to investigate the viability of developing an acidic agglomerated flux by utilizing wasted flux dust of the parent commercial acidic flux. The chemical composition and mechanical properties of the all-weld metal, prepared by using the developed acidic flux, were found to be in the same range as that of the weld metal, prepared from parent commercial acidic flux. The radiographic examination of the welded joint, made by developing the flux, was also found to be sound. Therefore the welding cost and pollution can be reduced, without any compromise in weld quality, by utilizing the developed flux, prepared from waste flux dust of the parent flux. Thus the work follows the concept of 'waste to wealth'.

There is a growing need for supplying repetitive pulsed power loads of increasing magnitudes up to several hundred megawatts or more in areas of radar, lasers, high-energy physics experiments and thermonuclear fusion. The nature of such loads can be expected to be as diverse as their applications. The pulsed power demands and corresponding reactive volt-amperes requirements are undesirable from the frequency and voltage fluctuation standpoint, even for the large utility power systems. Techniques for supplying large dc-pulsed loads from a relatively small size ac generator by means of inductive storage and the capacitor commutated converters are presented. A theoretical basis is provided for analyzing the converters which serve to minimize the effects of pulsed power and corresponding reactive volt-amperes. Energy transfer between the storage inductor and the pulsed load is permitted with minimal loss, at a readily controllable rate including the reversibility of power in case of inductive loads. Use of a simple control scheme is shown to provide a precise load voltage regulation which may be a requirement for certain applications. The greatest use of these circuits would be in supplying loads with pulse durations of a few milliseconds to many seconds or minutes.

This paper describes an algorithm for representing the transformer hysteresis. This algorithm is useful under transient conditions and has the capability of representing minor loops. It allows the multi-valued hysteresis behavior to be represented as a linear element at each instant of time. This algorithm has been implemented into the BPA Electro-Magnetic Transients Program (EMTP), which is widely used on numerous different computers.