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Precision abrasive machining processes such as ultrasonic machining are commonly employed to machine glasses, single crystals and ceramic materials for various industrial applications. Until now, precision machining of hard and brittle materials are poorly investigated from the fundamental and applied point of views. Taking into account the major technological importance of this subject to the production of functional and structural components used in high performance systems, it is often desired to estimate the machining rate for productivity while maintaining the desired surface integrity. The success of this approach, however, requires not only the fundamental understanding of the material removal on the microstructural scale but also the relationship between the machining characteristics and material removal rate in ultrasonic machining. In this study, the ultrasonic machining of glass was investigated with respect to mechanism of material removal and material removal rate (with basic machining parameters) with a mild steel tool using boron carbide abrasive in water as slurry. The analysis indicates that the material removal was primarily due to the micro-brittle fracture caused on the surface of the workpiece. For micro-brittle fracture mode, the relationship for the material removal rate, considering direct impact of abrasive grains on the workpiece, based on a simple fracture mechanics analysis has been established. The effect of machining conditions on material removal rate has been discussed. This research provides valuable insights into the material removal mechanism and the dependence of material removal rate on machining conditions and mechanical properties of workpiece material in ultrasonic machining.

Surface quality of the machined component is one of the most important criteria for the assessment of grinding process. The importance of the surface finish of a product depends upon its functional requirements. Since surface finish is governed by many factors, its experimental determination is laborious and time consuming. So the establishment of a model for the reliable prediction of surface roughness is still a key issue for grinding. In this study, a new analytical surface roughness model is developed on the basis of stochastic nature of the grinding process, governed mainly by the random geometry and the random distribution of cutting edges on the wheel surface having random grain protrusion heights. A simple relationship between the surface roughness and the chip thickness was obtained, which was validated by the experimental results of AISI 4340 steel in surface grinding.

Inconsistent fat-free mass (FFM) and muscle strength responses have been reported in randomized clinical trials (RCTs) administering testosterone replacement therapy (TRT) to middle-aged and older men. Our objective was to conduct a meta-analysis to determine whether TRT improves FFM and muscle strength in middle-aged and older men and whether the muscular responses vary by TRT administration route.Systematic literature searches of MEDLINE/PubMed and the Cochrane Library were conducted from inception through 31 March 2017 to identify double-blind RCTs that compared intramuscular or transdermal TRT vs. placebo and that reported assessments of FFM or upper-extremity or lower-extremity strength. Studies were identified, and data were extracted and validated by three investigators, with disagreement resolved by consensus. Using a random effects model, individual effect sizes (ESs) were determined from 31 RCTs reporting FFM (sample size: n = 1213 TRT, n = 1168 placebo) and 17 reporting upper-extremity or lower-extremity strength (n = 2572 TRT, n = 2523 placebo). Heterogeneity was examined, and sensitivity analyses were performed.When administration routes were collectively assessed, TRT was associated with increases in FFM [ES = 1.20 ± 0.15 (95% CI: 0.91, 1.49)], total body strength [ES = 0.90 ± 0.12 (0.67, 1.14)], lower-extremity strength [ES = 0.77 ± 0.16 (0.45, 1.08)], and upper-extremity strength [ES = 1.13 ± 0.18 (0.78, 1.47)] (P 0.001 for all). When administration routes were evaluated separately, the ES magnitudes were larger and the per cent changes were 3-5 times greater for intramuscular TRT than for transdermal formulations vs. respective placebos, for all outcomes evaluated. Specifically, intramuscular TRT was associated with a 5.7% increase in FFM [ES = 1.49 ± 0.18 (1.13, 1.84)] and 10-13% increases in total body strength [ES = 1.39 ± 0.12 (1.15, 1.63)], lower-extremity strength [ES = 1.39 ± 0.17 (1.07, 1.72)], and upper-extremity strength [ES = 1.37 ± 0.17 (1.03, 1.70)] (P 0.001 for all). In comparison, transdermal TRT was associated with only a 1.7% increase in FFM [ES = 0.98 ± 0.21 (0.58, 1.39)] and only 2-5% increases in total body [ES = 0.55 ± 0.17 (0.22, 0.88)] and upper-extremity strength [ES = 0.97 ± 0.24 (0.50, 1.45)] (P 0.001). Interestingly, transdermal TRT produced no change in lower-extremity strength vs. placebo [ES = 0.26 ± 0.23 (-0.19, 0.70), P = 0.26]. Subanalyses of RCTs limiting enrolment to men ≥60 years of age produced similar results.Intramuscular TRT is more effective than transdermal formulations at increasing LBM and improving muscle strength in middle-aged and older men, particularly in the lower extremities.

Budget literacy is defined as 'the ability to read, decipher, and understand public budgets to enable and enhance meaningful citizen participation in the budget process'. It is comprised of two main parts - (i) a technical understanding of public budgets, including familiarity with government spending, tax rates and public debt and; (ii) the ability to engage in the budget process, comprising of practical knowledge on day-to-day issues, as well as an elementary understanding of the economic, social and political implications of budget policies, the stakeholders involved and when and how to provide inputs during the annual budget cycle. Given that no international standards or guidelines have been established for budget literacy education to date, this book seeks to address this gap by taking stock of illustrative initiatives promoting budget literacy for youth in selected countries. The underlying presumption is that when supply-side actors in the budget process -- governments -- simplify and disseminate budget information for demand-side actors -- citizens -- this information will then be used by citizens to provide feedback on the budget. However, since citizens are often insufficiently informed about public budgets to constructively participate in budget processes one way to empower them and to remedy the problem of "budget illiteracy" is to provide budget-literacy education in schools to youth, helping them evolve into civic-minded adults with the essential knowledge needed for analyzing their government's fiscal policy objectives and measures, and the confidence and sense of social responsibility to participate in the oversight of public resources. This book elaborates on approaches, learning outcomes, pedagogical strategies and assessment approaches for budget literacy education, and presents lessons that are relevant for the development, improvement, or scaling up of budget literacy initiatives.

This report presents the results of an online survey administered in six southeastern European countries: Albania, Bosnia and Herzegovina, Kosovo, Macedonia, Montenegro and Serbia. The survey was aimed at gathering insights related to the operations and human rights approach of municipalone-stop shops delivering services to citizens. Findings show that the region’s municipal citizen service centers are generally aware of the impact that their activities have on human rights. In addition to complying with legal requirements to guarantee the rights of citizens and avoid discriminatory practices in service delivery, many citizen service centers actively promote universal access to public services. This is mostly accomplished by taking measures that foster theinclusion of vulnerable groups and by offering mechanisms that encourage participation and accountability, such as citizen feedback and complaint-handling mechanisms.

Countries across the globe are establishing new and improving existing citizen service centers (CSCs) to better serve their citizens. This note provides an overview of recent developmentsimpacting CSC operations as well as a CSC design guide meant to summarize essential issues that managers looking to establish CSCs may wish to consider. Part 1 lays out how four key themes—access, personalization, speed, and interaction—have shaped the latest innovations in citizenservice center design. These themes are linked to the increasing availability and spread of new technologies, which open new channels for governments to provide information and services to their citizens, and expand the potential for multichannel approaches. Based on these trends, part 2presents a CSC design guide which provides an overview of eight key issues to take into account when designing or reforming a CSC: (1) channels of service delivery; (2) depth of service delivery; (3) financing models; (4) organizations involved and breadth of services provided; (5) single or multiple windows; (6) homogeneity/diversity across CSCs; (7) location; and (8) if services are provided by target group, life event or category of service.

This case study analyzes the Huduma Kenya program, under which the Government of Kenya is advancing citizen-centered public service delivery through a variety of channels, including deploying digital technology and establishing citizen service centers across the country. The paper examines key topics related to the operation, from institutional arrangements, funding, and staffing to digitization, organizational culture, and customer feedback. The program has beenparticularly successful at forging an organizational culture focused on excellence in customer service, which revolves around improving transparency, efficiency, and integrity. This organizational culture helps motivate staff and level the playing field for citizens of all backgrounds to get equal service and treatment from the same place, an important step toward enhancing accessibility and nondiscrimination. The Huduma Kenya program takes a multichannel approach, combining brick-and-mortar centers with digital service platforms to ensure that citizens with differing levels of literacy and access to the Internet are reached while still keeping pace with the latest technological developments. To date, the primary challenges encountered in the rollout of the Huduma Centers concern the coordination among the various institutions involved in their management, staffing, and oversight; and the deployment of staff incentives related to compensation and professional development.

This case study analyzes the development of one-stop shops in the Socialist Republic of Vietnam, from inception of the first one in Ho Chi Minh City in 1995 through the full roll out of this model of integrated service delivery across the country, beginning in 2003. Embedded in the spirit of the “Doi Moi” reforms that began in the 1980s, one-stop shops have been an integral part of the government’s public administration reform program, initiated in 2001. Political support, decentralization, clear guidelines regarding organizational structure, and significant capital investment allowed the one-stop shop model to successfully transform the attitudes of civil servants toward the public, reduce bureaucracy, inefficiencies, and rent seeking, and improve the quality of services delivered.

This note provides practical advice on how to adopt a human rights-based assessment for the design, strategy, and implementation of service delivery by citizen service centers. Designed for World Bank teams conducting preliminary assessments, the tool presented here can also beuseful to clients such as citizen service center managers to deepen their understanding of the value of a human rights based assessment and to improve the quality, accessibility, and effectiveness of service delivery. The tool consists of an introduction to the human rights-based approach (HRBA), its relevance to citizen service centers, rationales for adopting the approach, and a 20-question survey instrument.

Ova studija slucaja pruža pregled Gradskog uslužnog centra u Pancevu (GUC) koji, od uspostavljanja 2009. godine, pruža citav niz opstinskih usluga građanima pod istim krovom. Studija istražuje mere koje je opstinski tim uveo kako bi garantovao jednak pristup uslugama za sve segmente populacije iunapredio kvalitet pruženih usluga, pogotovo prebacivanje određenih usluga online i obezbeđivanje mehanizama za brzu povratnu informaciju građanima. Dok su institucionalna koordinacija, finansiranje, motivacija zaposlenih i kapaciteti za ispunjavanje tražnje i dalje izazovi, GUC je postao glavna kontakt tacka opstine, a broj građana koji svake godine posete centar je gotovo jednak ukupnom broju stanovnika grada. Uspesi dostignuti kroz ovaj model jednosalterskog sistema nalokalnom nivou ukljucuju laksi pristup, vecu efikasnost, brže pružanje usluga, unapređenu komunikaciju i bolji kvalitet informacija za građane.

BACKGROUND: AIMS: To review the clinical features and management of patients with injuries related to the cobra bite. DESIGN: Retrospective study. METHODS AND MATERIAL: Patients who attended the hospital for cobra–bite related injuries from 1 April 2008 to 31 March 2009 were included. The data were obtained from the admission register, and snakebite case record sheets were then retrieved from the medical record section of hospital. Demographic data, time of occurrence, location of wound site, local and systemic complications, anti-venom therapy (number of vials), clinical outcome, any surgical intervention, and length of hospital stay were retrieved from the clinical records. RESULTS: Eighteen patients were recruited during the 1-year study period. Of the 18 patients with cobra bites, 14 (78 %) presented with local swelling. No patient developed severe neurotoxic symptoms. Two patients had laboratory features of haemolysis. Fourteen patients received antivenom therapy and five of them subsequently underwent surgical interventions for extensive local tissue damage and necrosis. There was no fatality. CONCLUSION: Bites from cobras result in serious local complications with extensive tissue necrosis and minimal neurotoxic symptoms. There is an apparent trend of favorable outcomes following the early administration of antivenom to patients without early signs of irreversible tissue damage. Ciprofloxacin should be used in infected wounds of cobra bite, if facilities for culture and sensitivity are not available.

Iron ore pellets are largely characterized by inherent physical and chemical properties of ore as well as pelletizing conditions including induration time, induration temperature, etc. These parame...

BACKGROUND: The HIV/AIDS pandemic has become a serious public health problem. As the prevalence of the infection rises, healthcare professionals worldwide can expect greater clinical exposure to infected patients. OBJECTIVES: 1. To study the source of information about HIV/AIDS among nursing students. 2. To assess the knowledge of nursing students regarding transmission & treatment of HIV/AIDS. 3. To study the attitude of nursing students towards PLWHA. METHODS: A cross sectional study has been done on nursing students of tertiary care hospital. Self- administered questionnaire were used to collect data. RESULTS: The results were obtained from 205 respondents. Most of the students are from 20-23 of age group. Majority of students (97.1%) heard about HIV/AIDS. 48.8% nursing students attended training programme on HIV/AIDS. About 61.5% nursing student's talk about HIV/AIDS in college. Association between gender & knowledge is significant (p=0.003). Knowledge was higher in males. Association between age & knowledge is significant (p=0.03). Knowledge increases with age. Based on present study findings students had positive attitude towards PLWHA. Knowledge and attitudes were not associated (ᵡ2 = 1.347, p= 0.510). CONCLUSION: The overall knowledge about the diseases was considered to be good among the study participants. Based on present study findings students had good level of positive and favorable attitude regarding HIV/AIDS prevention.

A significant quantity of chromite ore is available in form of fines and is friable in nature. Agglomeration is necessary for utilizing these fines. Briquetting gives green agglomerates with inferior high temperature properties. Pelletization requires further grinding of the naturally available ore fines and the subsequent firing of the green pellets for strength development which make it energy-intensive and complex process. In contrast, sintering can be done directly on the as-received friable chromite ore in the presence of coke breeze (as in case of iron ore sintering), which is likely to be free from the above limitations. In the current work, an optimum combination of temperature, flux (added to increase the relative quantity of molten phase required for sintering) and coke (added as fuel to attain the sintering temperature in a sinter pot) was computed using the thermochemical software, FactSage 6.1 and enthalpy balance calculation. Sintering of a mixture of chromite ore fines and flux with the optimum composition at 1600 C was carried out in; (i) resistance furnace (100-g scale), without using carbon and (ii) a pot sintering set-up (10-kg scale), using the computed quantity of carbon. A good correlation between experimental result and predicted equilibrium phases has been observed. The characterization of the sinters prepared in pot sintering set-up was done by conducting shatter, tumbler, and abrasion tests, and their phase identifications by XRD and EPMA/EDS. The developed sinter was found to possess adequate handling strength that would be well acceptable to produce ferrochrome in the SAF.

The grinding force and power play an important role in ceramic grinding process as they not only have the direct influence on the wheel wear, grinding accuracy, grinding temperature and surface integrity but also have strong influence on local contact deflection and the nature of the contact deflection that has an important effect on the mechanism of material removal. In addition, they are also important to many aspects of ceramic grinding process optimization, monitoring, and control. So the prediction of grinding force and power in ceramic grinding is essential. But, the force and power is governed by many factors and its experimental determination is laborious and time consuming. So the establishment of a model for the reliable prediction of grinding force and power is still a key issue for ceramic grinding. In this study, a new grinding force and power model is developed, for the reliable prediction of grinding force and power in ceramic grinding, based on a new analytical undeformed chip thickness model. This new analytical undeformed chip thickness model is developed on the basis of stochastic nature of the grinding process, governed mainly by the random geometry and the random distribution of cutting edges. The model includes the real contact length that results from combined contact length, due to wheel-workpiece contact zone deflection and the local deflection due to the microscopic contact at the grain level and contact length due to geometry of depth of cut. The proposed model is used to predict the total grinding forces and power in surface grinding. The new model has been validated by conducting experiments on a horizontal surface grinding machine by grinding silicon carbide with diamond grinding wheel. Results indicate that the proposed model shows a good agreement with the experimental data obtained from different kinematic conditions. It also results in a significant reduction in the grinding forces, as compared with that obtained by the force model developed based on the existing undeformed chip thickness model, under the same operating conditions, in silicon carbide grinding.

BACKGROUND: There is currently no consensus on the criteria for inclusion of new bariatric procedures into routine clinical practice. This study canvasses bariatric surgeons in an attempt to define these criteria. METHODS: Bariatric Surgeons from around the world were invited to participate in a questionnaire-based survey on SurveyMonkey ®. RESULTS: 396 bariatric surgeons, 337 International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) members, took the survey. Five clinical studies conducted under the strict monitoring of an Institutional Review Board would satisfy most surgeons (67.7 %, n = 266). When asked regarding the number of patients in these studies, a cumulative number of 500 patients would satisfy 64.5 % (n = 255) of the surgeons. Most respondents regarded endorsement by their national society and IFSO as 'very important' or 'extremely important'. An overwhelming 74.4 % (n = 294) felt that every new procedure should undergo a randomized comparison against one of the established alternatives like Roux-en-Y Gastric Bypass or Sleeve Gastrectomy. CONCLUSION: Evaluation of a new bariatric procedure in at least 5 adequately supervised clinical studies (four of which must be randomized comparisons with one of the existing alternatives) reporting at least 5 years results on a minimum of 500 patients would satisfy majority of bariatric surgeons for the inclusion of a new bariatric procedure into clinical practice. The findings of this survey are simply aimed at starting a discussion on this topic and cannot be used to influence the ground reality until an international consensus can be reached amongst experts. info:eu-repo/semantics/publishedVersion

The quality of the surface produced during ceramic grinding is important as it influences the performance of the finished part to great extent. The undeformed chip thickness is a variable often used to describe the quality of ground surfaces as well as to evaluate the competitiveness of the overall grinding system. Hence, the estimation of undeformed chip thickness can cater to the requirements of performance evaluation. But, the undeformed chip thickness is governed by many factors and its experimental determination is laborious and time consuming. So the establishment of a model for the reliable prediction of undeformed chip thickness is still a key issue for ceramic grinding. In this study, a new undeformed chip-thickness model is developed, for the reliable prediction of undeformed chip thickness in ceramic grinding, on the basis of stochastic nature of the grinding process, governed mainly by the random geometry and the random distribution of cutting edges. The model includes the real contact length that results from combined contact length, due to wheel–workpiece contact zone deflection and the local deflection due to the microscopic contact at the grain level and contact length due to geometry of depth of cut. The mechanical properties of workpiece material and the grinding parameters are also considered in the undeformed chip thickness model through normal grinding force model. The new model has been validated by the experimental results of silicon carbide grinding, taking the surface roughness as a parameter of evaluation.

The selection of optimum machining conditions, during wire electric discharge machining process, is of great concern in manufacturing industries these days. The increasing quality demands, at higher productivity levels, require the wire electric discharge machining process to be executed more efficiently. Specifically, the material removal rate needs to be maximized while controlling the surface quality. Despite extensive research on wire electric discharge machining process, determining the desirable operating conditions in industrial setting still relies on the skill of the operators and trial-and-error methods. In the present work, an attempt has been made to optimize the machining conditions for maximum material removal rate and maximum surface finish based on multi-objective genetic algorithm. Experiments, based on Taguchi’s parameter design, were carried out to study the effect of various parameters, viz. pulse peak current, pulse-on time, pulse-off time, wire feed, wire tension and flushing pressure, on the material removal rate and surface finish. It has been observed that a combination of factors for optimization of each performance measure is different. So, mathematical models were developed between machining parameters and responses like metal removal rate and surface finish by using nonlinear regression analysis. These mathematical models were then optimized by using multi-objective optimisation technique based on Non-dominated Sorting Genetic Algorithm-II to obtain a Pareto-optimal solution set.

Development of advanced ceramics such as silicon carbide has gained significant importance because of their desirable properties. However, their engineering applications are still limited owing to the limitations in developing damage-free and economical machining techniques. It is often desired to increase the machining rate to improve productivity while maintaining the desired surface integrity. The success of this approach, however, requires a fundamental understanding of the material removal and damage formation mechanism in grinding. In this paper, high removal rate grinding of silicon carbide was investigated with respect to material removal and basic grinding parameters using a diamond grinding wheel. The results showed that the material removal was primarily due to the microfracture and grain dislodgement under the grinding conditioned selected. For grain dislodgement removal mode, the relationship for the removal rate in scratching based on a simple fracture mechanics analysis has been established. This research provides valuable insights into the surface and subsurface integrity and material removal mechanism during high removal rate grinding of silicon carbide.

Background Low-density lipoprotein cholesterol (LDL-C) can either be calculated or measured directly. Clinical guidelines recommend the use of calculated LDL-C (C-LDL-C) to guide therapy because the evidence base for cholesterol management is derived almost exclusively from trials that use C-LDL-C, with direct measurement of LDL-C (D-LDL-C) being reserved for those patients who are nonfasting or with significant hypertriglyceridemia. Objective Our aim was to determine the clinical equivalence of directly measured-LDL-C, using a Siemens Advia Chemistry System, and fasting C-LDL-C. Methods Eighty-one subjects recruited for two cholesterol treatment studies had at least one C-LDL-C and D-LDL-C performed simultaneously; 64 had a repeat lipid assessment after 4 to 6 weeks of therapy, resulting in 145 pairs of C-LDL-C and D-LDL-C. Results There was significant correlation between D-LDL-C and C-LDL-C (r 2 = 0.86). Correlation was significantly better in those with lower total cholesterol, triglycerides, and high-density lipoprotein. In 60% of subjects, the difference between D-LDL-C and C-LDL-C was more than 5 mg/dL and greater than 6%. Clinical concordance between D-LDL-C and C-LDL-C was present in 40% of patients, whereas clinical discordance was noted in 25%. One-third had greater than a 15 mg/dL difference between D-LDL-C and C-LDL-C, whereas 25% had a greater than 20 mg/dL difference. In 47% of subjects, the difference between D-LDL-C and C-LDL-C at baseline and follow-up changed by a minimum of 10% or 10 mg/dL. Conclusions Our findings suggest that D-LDL-C is not clinically equivalent to C-LDL-C. This puts into question the current recommendation of using D-LDL-C in situations in which C-LDL-C would be inaccurate.

A 39-year-old female patient with hepatitis B-related decompensated chronic liver disease underwent living donor liver transplantation. Preoperatively, she had a normal electrocardiogram (ECG) and echocardiography, and also a negative dobutamine stress echocardiography test. Intraoperative course went uneventful. Two hours postoperatively, she developed hypotension. Initially, hypotension was treated with fluids and blood products after confirming normal echocardiography, but with time, patient's haemodynamics worsened. Repeat echocardiography showed postero-inferior regional wall motion abnormality. Troponin I was significantly elevated, but ECG was normal. Suspecting myocardial infarction coronary angiography was done which was normal. Based on Mayo's criteria, patient was diagnosed with reverse Takotsubo cardiomyopathy since postero-inferior wall was involved. Inotropic support failed to maintain haemodynamics and intra-aortic balloon pump (IABP) was placed. Inotropes were gradually tapered and IABP was removed at day 4. Twenty days later, repeat echocardiography was normal and patient was subsequently discharged.

The rehabilitation of patients affected by posterior maxillary atrophy by the aid of implant-supported fixed prosthesis presents a challenge in many cases. The available residual alveolar ridge is insufficient for the placement of dental implants because of alveolar bone resorption, pneumatization of the maxillary sinus, or their combination. Maxillary sinus floor augmentation is the treatment of choice in such cases. Sinus lift procedure can be carried with or without simultaneous implant placement. Recently, various newer techniques have been introduced for sinus floor elevation such as antral membrane balloon elevation, water lift technique, and piezosurgery. Furthermore, short implants and zygomatic implants can also be done in severe posterior atrophied maxilla.

This paper addresses the adoption and applicability of International Accounting Standards (IAS) and International Financial Reporting Standards (IFRS), issued by the International Accounting Standards Board (IASB) to India. Specifically, the paper highlights some major areas where the country lacked harmonization with IAS in 1993 and the rapid congruence with IAS in the decade that followed. The attempt to achieve congruence with IAS appears to be more a by-product of the country's rapid economic growth rather than its catalyst. However, continued growth and the attraction of foreign capital to domestic ventures will depend on the transparency of the financial dealings. The Institute of the Chartered Accountants of India, (ICAI), India's standard setting body, is increasingly attempting to provide this transparency by revisions and additions to accounting standards, and by Exposure Drafts which aim to bring India more in line with International Financial Reporting Standards.

The difficulty and cost involved in the abrasive machining of hard and brittle ceramics are among the major impediments to the widespread use of advanced ceramics in industries these days. It is often desired to increase the machining rate while maintaining the desired surface integrity. The success of this approach, however, relies in the understanding of mechanism of material removal on the microstructural scale and the relationship between the grinding characteristics and formation of surface/subsurface machining-induced damage. In this paper, grinding characteristics, surface integrity and material removal mechanisms of SiC ground with diamond wheel on surface grinding machine have been investigated. The surface and subsurface damages have been studied with scanning electron microscope (SEM). The effects of grinding conditions on surface/subsurface damage have been discussed. This research links the surface roughness, surface and subsurface damages to grinding parameters and provides valuable insights into the material removal mechanism and the dependence of grinding-induced damage on grinding conditions.

Isolongifolene and various other isolongifolene-based products are commercially important chemicals that find applications in perfumery and fragrance industry. These important commodity chemicals are generally prepared by homogeneous catalyzed reactions of longifolene in liquid phase. In the present study, role of acidity and acid distribution on montmorillonite, pillared interlayered clay and modified pillared clay catalysts have been studied for the first time in vapor phase system for the conversion of longifolene to isolongifolene. The number and strength of acid sites of montmorillonite clay mineral have been modified by steps of synthesis and by cations selection. Reaction of Al- pillared montmorillonite with Ru 3+ yielded a catalyst with significantly higher distribution of weak acid sites while fortification of montmorillonite with Ce 3+ and La 3+ had little effect on total acidity and its distribution. In the present study, an attempt has been made to correlate the activity of the catalysts with total acidity, number and strength of the acid for the conversion of longifolene to isolongifolene. NH 3 TPD determined the concentration and strength of acid sites.

Heat produced during ceramic grinding, due to high specific energy and high wheel-workpiece friction, is critical in terms of workpiece quality. High heat generation at the grinding zone impairs the workpiece quality by inducing thermal damage in the form of surface and subsurface cracks, phase transformations, tensile residual stresses, etc. These damages can severely limit the application of ground ceramic components. Cooling and lubrication therefore, plays an important role during ceramic grinding. Conventional cutting fluids are often ineffective due to the phenomena like air barrier and film boiling effect. Further, these fluids have a direct influence both to human health and environment and therefore, being questioned in the light of economic and ecological manufacture. So, possible replacement of cutting fluids by something else is of great concern to the researchers in recent years. Demands for high operating temperatures, lower cost, longer life and better performance drive the search and use o...

In this paper Overall Exergy, Thermal gain Analysis has been carried out under the climatic condition of Jodhpur city, India for Type a Weather condition. Here a single PV module of dimension (1.2m×.54m) is taken for the analysis purpose. Here we will discuss two Cases. Case 1 is the single module of the given dimension. Now in order to increase the overall performance of PV module, we can arrange them in the form of Array. In Case 2 we connect them in series such that Output of First is the Input of second. PV/T Module is designed which generate both Thermal and Electrical energy. When solar radiation falls some part of it convert to Electricity while rest will increase the Temperature of Module. In order to reduce the Temperature analytical Expressions has been derived in terms of solar cell Temperature, back surface Temperature, inlet and outlet temperature, overall Thermal & Electrical Efficiency.

Product quality assurance is a very important concern in industries these days. Surface quality is an important constituent of overall product quality in ceramic grinding. Surface roughness is one of the major quality attributes of a ground product and hence it is used to determine and evaluate the quality of the product. Although the surface roughness evaluation has been standardized, establishment of a model for reliable prediction of surface roughness is still a key issue. This paper presents a new analytical model for the prediction of arithmetic mean surface roughness based on the stochastic nature of grinding process, governed mainly by the random geometry of grain and random distribution of cutting edges on the wheel surface having random grain protrusion heights. A simple relationship between the surface roughness and the chip thickness was obtained, which was validated by the experimental results of silicon carbide grinding.

The quality of the surface produced during ceramic grinding is important as it influences the performance of the finished part to great extent. Hence, the estimation of surface roughness can cater to the requirements of performance evaluation. But, the surface finish is governed by many factors and its experimental determination is laborious and time consuming. So the establishment of a model for the reliable prediction of surface roughness is still a key issue for ceramic grinding. In this study, a new analytical surface roughness model is developed on the basis of stochastic nature of the grinding process, governed mainly by the random geometry and the random distribution of cutting edges. This model has been validated by the experimental results of silicon carbide grinding. The theoretical analysis yielded values which agree reasonably well with the experimental results.

High-performance zinc oxide (ZnO) bottom-gate (BG) thin-film transistors (TFTs) with a single vertical grain boundary in the channel have been successfully fabricated by a novel low-temperature (i.e., 85°C) hydrothermal method. The ZnO active channel was laterally grown with an aluminum-doped ZnO seed layer underneath the Ti/Pt film. Consequently, such BG-TFTs (W/L = 250 μm/10 μm) demonstrated the high field-effect mobility of 9.07 cm2/V - s, low threshold voltage of 2.25 V, high on/off-current ratio above 106, superior current drivability, indistinct hysteresis phenomenon, and small standard deviations among devices, attributed to the high-quality ZnO channel with the single grain boundary.

Micro-electrical discharge machining (μ-EDM) is a non-traditional manufacturing technique that has been widely used in the production of precision engineering components throughout the world in recent years. The most important performance measure in μ-EDM is the surface roughness. The Silicon Carbide is a reaction bonded advanced ceramic that is the fourth hardest material after Diamond, boron nitride and boron carbide. Due to low fracture toughness, machining of Silicon Carbide is accomplished with EDM. In this study, the experimental studies were conducted under varying gap voltage, capacitance and threshold. The numbers of experiments were reduced by L9 array of Taguchi’s theory of DOE. Signal-to-noise (S/N) ratio was employed to determine the most influencing levels of parameters that affect the surface roughness in the μ-EDM of conductive silicon carbide. To validate the study, confirmation experiment has been carried out at optimum set of parameters and predicted results have been found to be in good agreement with experimental findings. A fuzzy logic model for predicting surface roughness during μEDM was also developed on MATLAB software and the goodness of fit of predicted values with experimental values was tested using chi-square test.Copyright © 2014 by ASME

The aluminium alloys are widely employed in the aeronautical, aerospace and automotive industries as they provide good heat conductivity, corrosion resistance, high strength to weight ratio even at high temperatures. Cutting fluids are still widely used in the machining of aluminium alloys to cope with problems associated with the heat generation. However, the growing social concern towards environmental conservation has made it necessary to develop cleaner production technologies such as dry machining in which no cutting fluids are employed. Solid lubricant assisted machining is a novel concept to control the machining zone temperature without polluting the environment. The surface quality of the machined parts is one of the most important product quality characteristics and one of the most frequent customer requirements. The present study focuses on investigating the effect of boric acid powder as solid lubricant on surface quality. Experiments have been conducted using Taguchi’s L9 orthogonal array. The influence of machining parameters viz. cutting speed, feed, rake angle and tool nose radius on surface quality has been investigated.

Noise coupling at various nodes within the loop during start-up is one of the reasons that make PLL not to start-up or lock within specified lock time. Therefore a robust PLL design is required to counter these effects of noise. In this paper the novel comparator integrated charge pump PLL is discussed. Simulation and characterization were performed to observe the integrated PLL behavior across voltage and temperature. The programmable PLL was designed for reference input clock of 10 to 30MHz and maximum output frequency of 100MHz. Internal nodes of the chip were probed to observe the behavior of individual blocks (Comparator, Phase frequency detector, Charge pump, VCO and P/Q dividers) of the integrated charge pump PLL chip. Comparing the characteristics with the conventional PLL, the proposed PLL showed no lock time and start-up issue in the presence of noise at VCO output and feedback dividers.

A gel filtration chromatographic packing was modified to contain immobilized silver ions in order to study the retention and binding behavior of biotin-Iabeled b-dUTP versus dUTP. The immobilized silver column retains unlabeled dUTP (with the retention time depending on sodium chloride concentration in the mobile phase), but no affinity binding is evident with dUTP. In the absence of sodium chloride, dUTP was seen to have a retention time of 66 minutes using a 10.3-mL immobilized silver column, while b-dUTP is fully bound to the immobilized silver column. Approximately 90% of b-dUTP is recovered when b-dUTP is applied to the immobilized silver column using 103 M PBS and eluted using M NaCl in the mobile phase. These results demonstrate the potential for using silver ions in immobilized soft metal affinity chromatography (ISMAC) in order to selectively target biotin labeled molecules. An analysis of the data yielding mathematical models with specific focus on the interaction between chloride and s...