Superconductivity in 2-2-3 system Y2Ba2Cu2O(8+delta)

Researchers synthesized a new high T(sub c) 2-2-3 superconductor Y2Ba2Cu3O(8+delta) by a special preparation technique and characterized it by ac-susceptibility measurements. Diamagnetism and Meissner effect sets in at low fields and superconducting transition onsets at 90 K. The systematic investigation of the real and imaginary components of ac-susceptibility as a function of temperature and applied ac magnetic field reveals that the magnetic behavior is that of a granular type superconductor

Synthesis and Biological Evaluation of Metal Chelates

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Reflective portfolios support learning, personal growth and competency achievement in postgraduate public health education

Background. Portfolios are increasingly used across a range of disciplines in health professional education to support reflective practice and to help assess students’ academic and professional development. However, their value in postgraduate education is uncertain.Objectives. To identify the role of portfolios in the development and assessment of professional competencies in postgraduate maternal and child public health education.Methods. A qualitative retrospective review of 35 student portfolios was conducted. Thematic content analysis of portfolios was done, identifying emerging themes and analysing patterns.Results. Two major themes were explored – the benefit of the portfolio to the student and to faculty. For students, portfolios promoted reflective abilities and critical thinking and assisted them in planning learning needs. For faculty, the portfolios assisted in monitoring students’ growth over time, identified learning gaps, helped to establish if expected learning outcomes were being attained and provided feedback on students’ application of academic learning to professional practice. Portfolios also offered students an opportunity to provide critical feedback on curricula content and course pedagogic activities.Conclusion. Portfolios are an under-utilised assessment and self-development tool in postgraduate training. They allow students to self-assess their attainment of personal learning needs, professional growth and competency achievement and provide faculty with useful feedback on curriculum content, educational activities and competency attainment

QQˉQ\bar Q (Q∈{b,c}Q\in \{b, c\}) spectroscopy using Cornell potential

The mass spectra and decay properties of heavy quarkonia are computed in nonrelativistic quark-antiquark Cornell potential model. We have employed the numerical solution of Schr\"odinger equation to obtain their mass spectra using only four parameters namely quark mass ($m_c$, $m_b$) and confinement strength ($A_{c\bar c}$, $A_{b\bar b}$). The spin hyperfine, spin-orbit and tensor components of the one gluon exchange interaction are computed perturbatively to determine the mass spectra of excited $S$, $P$, $D$ and $F$ states. Digamma, digluon and dilepton decays of these mesons are computed using the model parameters and numerical wave functions. The predicted spectroscopy and decay properties for quarkonia are found to be consistent with available experimental observations and results from other theoretical models. We also compute mass spectra and life time of the $B_c$ meson without additional parameters. The computed electromagnetic transition widths of heavy quarkonia and $B_c$ mesons are in tune with available experimental data and other theoretical approaches

Thermodynamic & Transport Properties of Aqueous Solutions of Fluoro-, Chloro-, Bromo-, & Iodoacetic, Propionic & Butyric Acids

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Optimization of vibration amplitude ratio of face mill tool of VMC and analysis with design expert to endorsing shim design

This paper presents the concept, design and development of shim (passive damper) to improve the stability for high spindle speed machine operation of face mill tool. The objective of this paper is to learning the dynamic behavior of a face mill tool on VMC with dissimilar types of shims which cover investigation of dynamic motion behavior of the face mill tool, the behavior of different types of shim design and behavior of vibration by using the amplitude ratio method and analysis by a Design Expert. Research work supported computational analysis with Ansys, 35 VMC experimental records and analyzed by ANOVA/Design Expert with different type of shims to observe a dynamic behavior of chatter. It include of the effect of process parameters like Cutting speed (250,200,150 m/min), feed per tooth (0.05, 0.1, 0.15mm/tooth), depth of cut (1.2 mm, 1.0 mm, 0.8 mm), and different types of materials (shims) for face mill tool on VMC, for analyzing the responses like amplitude ratio in X – direction, Y- direction with ANOVA and optimizing for AISI 2062 steel by Design Expert. An experimental methodology was developed using the DOE (Design of experiment) technique. The optimum factorial method was used to design an orthogonal array of four factors having three levels. Here, the main results are based on amplitude ratio, ANOVA analysis and optimization. ANOVA was used to decide the effects of the machining parameters on the vibration amplitude ratio in X; and vibration amplitude ratio in Y. This is useful for evaluating the stability of milling operations via time domain FFT and analyzed by ANOVA. Data are validated by 35 sets of VMC experiments. Physical 35 experiments may be not enough in a view of high level researchers, academicians and industrialist to conclude the use of shim and it need in face mill tool on VMC. Hence here optimization based on optimum factorial method is executed using Design Expert software in which 35experiments and its iterations with 70 populations were used to run the program. It is found that the most critical parameter in this study is the material of Shim. At high cutting parameters carbide shim, at low and medium cutting parameters SS shim are given better results by ANOVA and Optimization of Design Expert also validated by 35 sets of VMC experiments. Hence these shim designs endorse versatile solutions