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Search Results: 1 - 10 of 140 matches for " Beena Jaykumar "
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TL Glow Curve Study, Kinetics, PL and XRD Analysis of Mn2+ Doped CaAl2O4 Phosphors  [PDF]
Jagjeet Kaur, Nemana Subramanyam Suryanarayana, Beena Jaykumar, Vikas Dubey, Ravi Shrivastava, Huma Nazli Baig
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2012, DOI: 10.4236/jmmce.2012.1111114
Abstract: The present paper reports Thermoluminescence (TL) Glow curve of Mn2+ doped CaAl2O4 phosphor with different UV exposure time. The Glow peak shows general order kinetics and evaluation of kinetic parameters was done by peak shape method. Calculations of Trap Depth were done with Chen’s different methods and order of kinetics, activation energy and frequency factor are calculated. The recorded glow curve shifts towards higher temperature with increasing intensity as a function of UV exposure time until 30 minutes where it is seen that the peak shifts towards low temperature side and intensity also decreases. The peaks were found at 345?C, 356.83?C, 358?C and 356.73?C respectively using the heating rate 6.7?C/s. The PL (photoluminescence) excitation spectra show peaks at 248 nm and 362 nm whereas emission spectra shows peaks between 364 nm and 551 nm. Sample was characterized by XRD technique.
Catalytic Feedstock Recycling of Polymers  [PDF]
Raju Francis, Beena Sethi
Advances in Materials Physics and Chemistry (AMPC) , 2012, DOI: 10.4236/ampc.2012.24B067
Abstract: This piece of study involves degradation of plastic waste in presence of two different catalysts. It was found in gas chromatography (GC) analysis results that in presence of these catalysts more than 80% of polymer by weight was converted into either liquid or gaseous hydrocarbons. These can be utilized as fuel or can be transformed into other useful products. Thermo gravimetric analysis (TGA) and differential scanning calorimetric (DSC) analysis of polymers suggest that presence of these catalysts lowers degradation temperature and change mechanism of degradation.


Design of 2,4-Dichlorophenoxyacetic Acid Imprinted Polymer with High Specificity and Selectivity  [PDF]
Kizhakekuthiathottil Mathew Annamma, Mathew Beena
Materials Sciences and Applications (MSA) , 2011, DOI: 10.4236/msa.2011.23017
Abstract: A widely used herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) was imprinted on poly (4-vinylpyridine) (4-VP) using (40%) ethyleneglycol dimethacrylate (EGDMA) as crosslinking agent. The classical imprinting technology makes use of a high degree of crosslinking which does not allow the template molecules to move freely. So the binding sites, located in the central area of the three dimensional polymer matrix are hard to be accessed and the template molecules cannot be extracted totally. But here we propose a low crosslinked system with high specificity and selectivity. The imprinted and non-imprinted polymers were characterized by various spectroscopic techniques. The extent of binding was followed by batch equilibration method and compared with the respective non-imprinted polymer. Conditions for maximum specific rebinding were set by altering certain factors like template/monomer ratio, concentration of template solution, rebinding medium, mass of polymer and time of incubation. The selectivity of the imprinted polymer was investigated by comparing the binding with structural analogues of 2,4-D like, phenoxyacetic acid (POA), 4-chlorophenoxyacetic acid (4-CPOA) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T). The imprinted polymer exhibited high affinity towards the template molecule and was selectively rebound to the specific sites. The binding towards the structural analogues depends on the number of chlorine in the benzene ring.
Time-Frequency Analysis of Asymmetric Triaxial Galaxy Model Including Effect of Spherical Dark Halo Component  [PDF]
Beena R. Gupta, Vinay Kumar
International Journal of Astronomy and Astrophysics (IJAA) , 2015, DOI: 10.4236/ijaa.2015.52014
Abstract: A method of time-frequency analysis (TFA) based on wavelets is applied to study the phase space structure of three-dimensional asymmetric triaxial galaxy enclosed by spherical dark halo component. The investigation is carried out in the presence and absence of dark halo component. Time-frequency analysis is based on the extraction of instantaneous frequency from the phase of the continuous wavelet transform. This method is comparatively fast and reliable. This method can differentiate periodic from quasi-periodic, chaotic sticky from chaotic non-sticky, ordered from chaotic and also, it can accurately determine the time interval of the resonance trapping and transitions too. Apart from that, the phenomenon of transient chaos can be explained with the help of time-frequency analysis. Comparison with the method of total angular momentum (denoted as Ltot) proposed recently is also presented.
The Fluorescence of Pr3+ in Zinc Lithium Bismuth Borate Glasses with Large Stimulated Emission Cross Section  [PDF]
Beena Bhatia, S. L. Meena
New Journal of Glass and Ceramics (NJGC) , 2016, DOI: 10.4236/njgc.2016.62002
Abstract: Glass sample of Zinc Lithium Bismuth Borate (25-x) Bi2O3:20Li2O:20ZnO:35B2O3:xPr6O11, (where x = 1, 1.5 and 2 mol%) has been prepared by melt-quenching technique. The amorphous nature of the prepared glass samples was confirmed by X-ray diffraction. The absorption spectra of three Pr3+ doped zinc lithium bismuth borate glasses have been recorded at room temperature. The observed optical spectra are discussed in terms of energy states and the intensity of the transitions. The various interaction parameters like Slater-Condon, Lande, bonding and Racah parameters have been computed. Judd-Ofelt intensity parameters and laser parameters have also been calculated. The stimulated emission cross section (σp) for the transition (3P03F2) is found to be in the range 3.12 - 10.43 * 10-20 cm2. The σp values are comparatively large suggesting the possible utilization of these materials in laser applications.
A retrospective study of the pattern of sexually transmitted diseases during a ten-year period
Narayanan Beena
Indian Journal of Dermatology, Venereology and Leprology , 2005,
Abstract: Background: Proper knowledge of the patterns of sexually transmitted diseases (STDs) in different geographical regions is necessary for evolving proper strategies for control of these diseases. Aims: To study the pattern of STDs and to analyze the changes during a ten-year period from 1990 among patients attending Medical College Hospital, Kottayam Methods: Case records of 686 patients with STDs who attended the outpatient wing of the Department of Dermatology and Venereology were studied. Results: There were 504 males and 182 females in the total of 686 patients. Marital contact alone was reported by 123 (67.6%) female patients. Genital ulcer diseases (GUDs) accounted for the maximum number of STDs, with 504 cases (73.5%), followed by condyloma acuminatum (17.5%) and gonorrhea (10.1%). Forty-three patients had multiple infections. The total number of patients during the first year of study was 129, while it was 41 during the last year. Bacterial STDs showed a striking reduction in numbers. The decline was less marked in the case of viral STDs. Conclusion: The majority of patients had genital ulcer diseases. Spouses were the most common source of infection for female patients. There was a marked decline in the number of patients with various STDs during the ten-year period. The decline was more evident in the bacterial STDs resulting in an apparent increase of the viral STDs towards the end of the period of study.
Psychological Comorbidity in Children and Adolescents with Learning Disorders
Beena Johnson
Journal of Indian Association for Child and Adolescent Mental Health , 2005,
Abstract: Learning disabilities are frequently associated with psychological problems (Rutter, 1974; Willcutt and Pennington, 2000). Results of population based surveys suggest that about 30% of learning disabled children have behavioural and emotional problems (Mc Gee et al, 1984). Psychopathology worsens with age in children with non-verbal learning disabilities (Rourke, 1988). Marked anxiety can appear when children with dyscalculia are confronted with reasonably simple arithmetic problems (Garnett and Fleischner, 1987). Ekblad (1990) found a positive correlation between psychological disturbance and poor school achievement among Chinese children. Shenoy & Kapur (1996) noted that 21 out of 88 children with learning disability had a comorbid psychological diagnosis. Kishore et al (2000) reported that 21 out of 56 children with specific developmental disorders of scholastic skills had a comorbid psychological disorder.
Spontaneous Gender Categorization in Masking and Priming Studies: Key for Distinguishing Jane from John Doe but Not Madonna from Sinatra
Ruth Habibi, Beena Khurana
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0032377
Abstract: Facial recognition is key to social interaction, however with unfamiliar faces only generic information, in the form of facial stereotypes such as gender and age is available. Therefore is generic information more prominent in unfamiliar versus familiar face processing? In order to address the question we tapped into two relatively disparate stages of face processing. At the early stages of encoding, we employed perceptual masking to reveal that only perception of unfamiliar face targets is affected by the gender of the facial masks. At the semantic end; using a priming paradigm, we found that while to-be-ignored unfamiliar faces prime lexical decisions to gender congruent stereotypic words, familiar faces do not. Our findings indicate that gender is a more salient dimension in unfamiliar relative to familiar face processing, both in early perceptual stages as well as later semantic stages of person construal.
Nutrient Accumulation in Various Plant Parts of Dominant Tree Species of Three Different Localities
Beena Sharma,Kavita Sharma
Pakistan Journal of Biological Sciences , 2013,
Abstract: In the present study, accumulation of nutrients (N, P, Ca, Mg, and K) in various plant parts of three different dominant trees i.e., Acacia senegal (As), Acacia tortilis (At) and Eucalyptus camaldulensis (Ec) was estimated. Concentration of nutrients was estimated for bole, first order branch, other branch, foliage, seeds, stump root, lateral root and fine roots. The study was carried out in the sand dunes of Western foot hill gaps of Central Aravalli located at a distance of 10 km n-w to Ajmer, a centrally situated city of Rajasthan. The concentration of nutrients was found to be maximum in foliage except for nitrogen which was estimated higher in seeds of A. senegal and A. tortilis. A different pattern was recorded for E. camaldulensis where N, Ca, and Mg were recorded maximum in other branch, while p and K in foliage parts. Result shows the concentration of nutrients in different tree components in the order: foliage>seeds> their branch>first order branch>bole, and in root components: fine root>lateral root>stump root. Total nutrient concentration was found to be maximum in As followed by At and Ec. It is concluded that the foliage component of various trees has maximum nutrient concentrations. There are marked variations in the concentration of different nutrients in each component.
A Study on Strategic Initiatives and Actions taken during a Banking Merger
Dr. Beena Salim
International Journal of Emerging Sciences , 2011,
Abstract: The present study focuses on the merger between two banking giants Emirates Bank and NBD in UAE. The study first focuses on the reasons behind this merger to give background information and then move forwards to identify the major strategic initiatives that the merged companies had to do to make the merger happen with less number of difficulties and to reap the benefits of the merger in the business environment. Krishnan and park [16] have observed that mergers commonly take place horizontally and mostly between direct competitors. Studies have proven that majority of the merger and acquisition activity lead to failures, with failure rates between 60 to 80 % [20], [27]. The study found that an initiated proactive change management plan, workshops, human deployment decisions, system integration decisions and finally rebranding did make their merger story a success. Early decisions related to human resource, Leadership involvement, Task integration, Employee engagement, system integration, customer integration and rebranding were the key areas that they concentrated in the change process.
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