Elliptic supersonic jet morphology manipulation using sharp-tipped lobes

Elliptic nozzle geometry is attractive for mixing enhancement of supersonic jets. However, jet dynamics, such as flapping, gives rise to high-intensity tonal sound. We experimentally manipulate the supersonic elliptic jet morphology by using two sharp-tipped lobes. The lobes are placed on either end of the minor axis in an elliptic nozzle. The design Mach number and the aspect ratio of the elliptic nozzle and the lobed nozzle are 2.0 and 1.65. The supersonic jet is exhausted into ambient at almost perfectly expanded conditions. Time-resolved schlieren imaging, longitudinal and cross-sectional planar laser Mie-scattering imaging, planar Particle Image Velocimetry, and near-field microphone measurements are performed to assess the fluidic behavior of the two nozzles. Dynamic Mode and Proper Orthogonal Decomposition (DMD and POD) analysis are carried out on the schlieren and the Mie-scattering images. Mixing characteristics are extracted from the Mie-scattering images through the image processing routines. The flapping elliptic jet consists of two dominant DMD modes, while the lobed nozzle has only one dominant mode, and the flapping is suppressed. Microphone measurements show the associated noise reduction. The jet column bifurcates in the lobed nozzle enabling a larger surface contact area with the ambient fluid and higher mixing rates in the near-field of the nozzle exit. The jet width growth rate of the two-lobed nozzle is about twice as that of the elliptic jet in the near-field, and there is a 40\% reduction in the potential core length. Particle Image Velocimetry (PIV) contours substantiate the results.Comment: 19 pages, 16 figures. Revised version submitted to Physics of Fluids for peer review. URL of the Video files (Fig. 6 & Fig. 14) are given in the text files (see in '/anc/*.txt'

History and Reconstruction of Thirugnanasambandar

Religious literature in Tamil is full of fiction with many unnatural events. Such stories were created for the development of religion. Beyond the tendency to approach them superficially as mere fiction, it is essential for the intelligent community to explore them on the basis that every fictional story has a background cause.Thus, the scriptures tell the story of Thirugnanasambandar, who is considered to be a Saiva (Devotee of Lord Siva) doing impossible deeds, differently from each other. This article reviews the obvious readings and reconstructions of the history of Thirugnanasambandar by Vannacharabam Dhandapani Swami in his Puluvar Puranam. They convey the oral stories and ideas about Thirugnanasambandar, that existed in the 19th century, as well as the logical study of history and the fictional background of antecedents

Adoption of Crop Insurance Schemes in Tamil Nadu

The study was conducted in Southern zone of Tamil Nadu a constituent state of India. One hundred and eighty farmers who had adopted crop insurance schemes were selected through random sampling procedure. The respondents were interviewed using a pre-tested questionnaire for identifying factors influencing and constraints in adoption of crop insurance schemes. The study revealed that lack of scope for crop diversification and definite crop loss due to adverse climatic condition were the major factors influencing the adoption of crop insurance schemes. The study inferred that lack of compensation from the crop insurance scheme, delayed payment of indemnity, lack of awareness about the scheme and lengthy procedure to avail crop insurance were the major constraints

BRIEF REVIEW OF SPECTROPHOTOMETRIC METHODS FOR THE DETECTION OF TETRACYCLINE ANTIBIOTICS

Antibiotics are one of the most common pharmaceutical products, used for the treatment of bacterial ,fungal and parasitic infections. Among antibiotics, tetracyclines are extensively used in both human and animal welfare. Hence the monitoring and estimation of the levels of tetracycline in pharmaceutical products and effluents have become a necessity for researchers and industries. Current methods for estimation are based on high-level technologies ,and suffer from several disadvantages such as being time consuming, expensive and require  extensive training to operate.Much focus has been made on the development of simple ,quick and inexpensive methods that can be used in a routine manner. Most methods use either redox reaction of the tetracycline using an oxidizing agent or the use of polyvalent cations for chelation and complexometric reactions. Spectrophotometric methods for detection of antibiotics are simple  but rare. The objective of this review article is to present an insight into the various spectrophotometric methods available for the detection of tetracycline, with data regarding the reagents, wavelength used for the measurement and optimum concentration range applicable for each method

Effects of selected asana practices on flexibility and balance among school level taekwondo athlete

To achieve the purpose of this study, a school level taekwondo Athlete were selected from Premier Vidya Vikash School, Coimbatore. The selected (N= 30) thirty subjects were randomly divided into two equal groups (n-15), experimental group named as asana programme and control group. The pre-test was conducted on selected physiological variables (flexibility and balance), for all the groups. The readings were carefully regarded in the respective unit as pre-test score. After pre-test experimental group was treated with sit and reach test and stork balance test programme and the control group was not treated with any special programme. They kept as a control group. The subject was tested on criterion measures on flexibility – Sit and Reach Test and balance- Stroke balance the readings were carefully recorded in their respective units as pre-test score. The experimental groups underwent the respective training schedule one half hour per day in the morning session for a period of six weeks. After completion of 6 weeks of training, all the two groups were tested again on flexibility and balance the scores were recorded in their respected units as post-test scores. The pre and post test scores were taken for appropriate statistical analysis. In order to find out the significant changes if any paired ‘t’ ratio was be applied 0.05 level of confidence. The present study experimented effects of selected asana practices on flexibility and balance among school level taekwondo athlete. The result of this study indicated that there was is a change in flexibility and balance due to the proper planning, preparation, and execution of the training package given to the athlet

Functional Outcome of Percutaneous Pinning and Plaster for Distal Radius Fractures in Postmenopausal Women

INTRODUCTION: Fractures at the distal end of radius accounts for around 18 to 20 % of all skeletal fractures occurring in adults . Fractures around the distal radius account for around 19 % of all fractures in the postmenopausal aged females. Osteoporotic fractures are more common among the postmenopausal females due to the lack of osterogenic support. The fracture is most vulnerable at the distal end of radius where the trabecular bone is dominating and the cortical bone is thinner towards the radiocarpal joint. Many factors causing this risk are mineral changes in the bone, increased osteoblastic and osteoclastic turnover rates, underlying osteoporosis, long term steroid intake, underlying systemic disease etc. Distal radius fractures that occur in older postmenopausal women, five to six times more frequent in females than in males, and between the ages of 55– 85 years , with the peak incidence between 70 to 80 years. The distal radius fractures can occur in bimodal age groups (aged 17-25 years) involving in sports activities undergoing a relatively highenergy significant fall, and in geriatric persons (aged >50 years) with osteoporotic bone undergoing a simple low velocity fall, stress or a bump. Osteoporotic postmenopausal females with low mineral density have a greater incidence. AIM : The main aim of my prospective study is to determine the” functional outcome of Percutaneous pinning for distal radius fractures in post menopausal women’ . OBJECTIVES : 1. To analyse the role of minimal invasive surgical technique for distal radius fracture among post menopausal women. 2. To evaluate the functional outcome of percutaneous pinning with conservative methods. 3. To evaluate the role of percutaneous pinning as day care procedure. MATERIALS AND METHODS: A prospective cohart study of “functional outcome of distal radius fractures with percutaneous k wire pinning and plaster application” is done in Coimbatore medical college hospital, Coimbatore. The present study is conducted on 13 patients who are diagnosed to have distal end of radius fracture and being admitted in Coimbatore medical college hospital, Coimbatore during one year period of July 2014 to July 2015. Detailed written Informed consent was obtained from all the patients. Study design: An prospective cohart observational study. The age group ranges between 45 to 65 years . Inclusion criteria: 1. Postmenopausal women. Exclusion criteria 1. women in menstrual phase. 2. children ( 0-14 yrs) and males. 3. associated chronic co- morbidities. RESULTS: A prospective observational study was conducted on twenty five postmenopausal patients to analyse the functional outcome of percutaneous pinning and plaster with both intraarticular and extra articular distal radius fractures in Coimbatore medical college hospital for a period of one year between July 2014 to July 2015. In our study, the mean age of postmenopausal women was 57.6 years. The average follow up period was 6 months. The results obtained from our study were analysed in many aspects with previous other similar observational studies and were postulated as follows. CONCLUSION: Distal radius fractures are more common injuries occurring in geriatric population particularly among the postmenopausal women with underlying osteoporosis. The mode of violence is mostly a low velocity fall during the household activities. High velocity injuries are mostly encountered during road traffic accidents. Majority of the fractures are said to be extra -articular displaced with dorsal angulation in postmenopausal women typical of colle's However, higher degree of violence may produce intra articular displaced and communited fractures. The fracture union time on an average is found to be around 6 weeks. The anatomical reduction and radiological parameters are found to be obtained and maintained by crossed pinning providing a successful functional outcome and early range of motion in wrist joint. Percutaneous pinning with k – wires are just a minimally invasive day care procedure meeting the patients demands . Percutanous pinning is a valuable procedure to prevent subsequent fracture secondary displacements with least complications. Further, the procedure is so economical and less time consuming and doesn’t need a longer learning curve compared other modalities of treatment. The results of over study showed that proper reduction and positioning of k wire would provide a satisfactory outcome among the low demand groups

Study on heat treatment temperature of the corrosion performance

In this work the effect of titanium particles on wear of electro less Ni–P–TiO2 composite coatings deposited on mild steel substrates at different annealing temperatures. Electro less process is an autocatalytic reduction method in which metallic ions are reduced in the solution. Micro composite coatings of Ni-P-TiO2 on mild steel are deposited by varying volume of TiO2 nano-powder by electro-less method from Ni-P plating bath containing Nickel chloride as a source of nickel ions, sodium hypophosphite as the reducing agent, ammonium hydroxide as a complexing agents and TiO2 micro powder. Electroless Ni-P-TiO2 coating have been widely used in the chemical process industries, mechanical industries, and electronic industries due to their excellent mechanical properties. In the present work, deposition of Ni-P alloy coating and Ni-P-TiO2 micro composited coatings were done on the mild steel and hardness properties were studied.  &nbsp

STUDY ON THE CHEMICAL CONSTITUENTS OF THE ESSENTIAL OIL FROM NYCTANTHES ARBOR-TRISTIS AND ITS MOLECULAR DOCKING STUDIES

Objectives: The objectives of this study were to determine the chemical composition of the essential oil obtained from the flowers of Nyctanthes arbor-tristis (NAT) and to carryout molecular docking studies against three bacterial proteins to study the mechanism of the antibacterial activity. Methods: The essential oil was obtained from the flowers of NAT by hydrodistillation and the chemical composition was determined by gas chromatography–mass spectrometry analysis. Docking study was carried out for 14 compounds identified from NAT against three bacterial proteins 1UAG, 3TYE, and 3UDI. Results: Fourteen compounds were identified in the essential oil. 1-octanol (74.81%) is the predominant compound followed by phytol (6.80%), bis (2-ethylhexyl) phthalate (5.88%), and eucarvone (4.23%). Many compounds are similar to that of the essential oil from jasmine. Among the 14 compounds identified, 7,9-di-tert-butyl-1-oxaspiro (4,5) deca-6,9-diene-2,8-dione interacted well with 1UAG and 3TYE and showed binding scores of −8.9 and −7.2 K Cal/mol, respectively, involving hydrophilic and hydrophobic interactions. With the protein 3UDI, the compound eucarvone exhibited a binding score of −7.1 K Cal/mol. Conclusion: The similarities between the essential oil constituents of flowers the two plants NAT and jasmine. Therefore, it could be concluded that NAT flowers of Coimbatore are a good source of fragrance for cosmetic industry and as an antibacterial agent

EFFECT OF SALINITY GRADIENT SOLAR POND UPON ADDITION OF CaCO3

This study involves the experimental optimisation of the performance of with and without adding CaCO3 in solar pond. The experiment was carried out at Government College of Engineering, Salem, India. Readings were taken for a period of 10 days. The temperature distribution and the amount of heat energy stored were evaluated. For comparison of ambient temperature and three convective zones temperature, the solar pond of volume 0.176 m3 and height of 0.45 m was constructed. The shape of the solar pond is trapezoidal and the inclination angle of the pond is 56º. The temperatures of the solar pond with and without adding CaCO3 were obtained as 50.7º C and 46º C respectively. The solar pond at lower convective zone (LCZ) indicated an increase of 10.2% in temperature. The difference between the amounts of heat energy stored is 12.6 kJ. From the result it is concluded that by adding CaCO3 increases the temperature of lower convective zone (LCZ) and also increases the amount of heat energy stored in the solar pond

Comparison of Measured and Predicted Performance and the Emission Characteristics of Single Cylinder CI Engine using Pongamia Pinnata based Bio-Diesel

Diesel being the main transport fuel, developing countries like India spends a lot of money to import petroleum and the use of petroleum based fuels increased in the recent years is the main contributor to the urban air pollution. Finding a suitable alternative to diesel is an urgent need. Biofuels are renewable, can supplement petroleum based fuels. Due to pressure on edible oils, non-edible oils of Pongamia Pinnata (karanja) and Jatropa Curcas are evaluated as diesel fuel extender. Pongamia pinnata based bio-diesel (PBD) is receiving increasing attention in India because of its potential to increase the rural employment and relatively low impact on environment. Diesel engines running on PBD are found to emit higher oxides of nitrogen. In this work a single cylinder constant speed water cooled four stroke direct injection diesel engine is selected for the experimental investigations to model the performance and emission characteristics fueled with plain Diesel and Pongamia Bio-diesel blends PBD10 (10% Pongamia Bio-diesel and 90% Diesel) and PBD20 (20% Pongamia Bio-diesel and 80% Diesel) with different cooled EGR rates (0%, 5%, 10%, 15% and 20%). The performance parameters are analyzed include specific fuel consumption and brake thermal efficiency whereas exhaust emissions include nitric oxide (NO), carbon monoxide (CO) and smoke opacity. The results of the experiments in each case were used to model the performance and emission parameters. Multivariate non linear regression analysis is carried out in Minitab software to model the performance and emission parameters. The predicted values were compared with experimental data