251 research outputs found
A simple functional form for proton-Pb total reaction cross sections
A simple functional form has been found that gives a good representation of
the total reaction cross sections for the scattering from Pb of
protons with energies in the range 30 to 300 MeV.Comment: 7 pages, 2 figure
Sustainable Development and the Philosophy of Grand National Happiness: Socio-Economic and Genetic Paradigm
The issue of development is based, in all forms and levels, on attaining equilibrium of development and environmental sustainability over time. Development is related to enhancement of the quality of human life in terms of increase in economic growth, infrastructure, industrial output, per capita income, adequate social security and polity, which is partly achieved by exploitation of nature or sometimes one section of people for the benefit of another section.Just as a gold medal has another face, development has also a dark hidden face. Development being an economic action tends to cause environmental damage. Environmental degradation disrupts the developmental process in the LDCs by imposing heavy cost on expenses on health as well as reduction on the productivity and human resources. In such a mad race of development, instead of growth statistics, the LDCs should look into a Grand National Happiness Index (GNHI) in framing the regional development co-ordinates. In this paper an attempt is made to highlight the philosophy of GNHI by encompassing socio-economic, genetic and environmental elements
A simple functional form for proton-nucleus total reaction cross sections
A simple functional form has been found that gives a good representation of
the total reaction cross sections for the scattering of protons from (15)
nuclei spanning the mass range Be to U and for proton
energies ranging from 20 to 300 MeV.Comment: 13 pages, 7 figures, bib fil
Total reaction cross sections for neutron-nucleus scattering
Neutron total reaction cross sections at 45, 50, 55, 60, 65, and 75 MeV from
nuclei 12C, 28Si, 56Fe, 90Zr, and 208Pb have been measured and are compared
with (microscopic) optical model predictions. The optical potentials were
obtained in coordinate space by full folding effective nucleon-nucleon
interactions with realistic nuclear ground state density matrices. Good to
excellent agreement is found.Comment: 5 pages, 1 figure, RevTeX
Role of microenvironment in the mixed Langmuir-Blodgett films
This paper reports the pi-A isotherms and spectroscopic characteristics of
mixed Langmuir and Langmuir-Blodgett (LB) films of non-amphiphilic carbazole
(CA) molecules mixed with polymethyl methacrylate (PMMA) and stearic acid (SA).
pi-A isotherm studies of mixed monolayer and as well as also the collapse
pressure study of isotherms definitely conclude that CA is incorporated into
PMMA and SA matrices. However CA is stacked in the PMMA/SA chains and forms
microcrystalline aggregates as is evidenced from the scanning electron
micrograph picture. Nature of these aggregated species in the mixed LB films
has been revealed by UV-Vis absorption and fluorescence spectroscopic studies.
The presence of two different kinds of band systems in the fluorescence spectra
of the mixed LB films have been observed. This may be due to the formation of
low dimensional aggregates in the mixed LB films. Intensity distribution of
different band system is highly sensitive to the microenvironment of two
different matrices as well as also on the film thicknessComment: 11 pages, 5 figure
Predicting proton-nucleus total reaction cross sections up to 300 MeV using a simple functional form
Total reaction cross sections are predicted for proton scattering from various nuclei. A simple functional form has been used that reproduces the total reaction cross sections for the scattering of protons from (15) nuclei spanning the mass range from Be to U and for proton energies 10 to 300 MeV
Photophysical characterizations of 2-(4-Biphenylyl)-5 phenyl-1,3,4- oxadiazole in restricted geometry
Langmuir and Langmuir-Blodgett (LB) films of nonamphiphilic
2-(4-Biphenylyl)-5 phenyl-1,3,4- oxadiazole (abbreviated as PBD) mixed with
stearic acid (SA) as well as also with the inert polymer matrix poly(methyl
methacrylate) (PMMA) have been studied. Surface pressure versus area per
molecule (-A) isotherms studies suggest that PBD molecules very likely stand
vertically on the air-water interface and this arrangement allows the PBD
molecules to form stacks and remain sandwiched between SA/PMMA molecules. At
lower surface pressure phase separation between PBD and matrix molecules occur
resulting due to repulsive interaction. However at higher surface pressure PBD
molecules form aggregates. The UV-Vis absorption and Steady state fluorescence
spectroscopic studies of the mixed LB films of PBD reveal the nature of the
aggregates. H-type aggregates predominates in the mixed LB films whereas I-type
aggregates predominates in the PBD-PMMA spin coated films. The degree of
deformation produced in the electronic levels are largely affected by the film
thickness and the surface pressure of lifting.Comment: 15 pages, 6 figure
Dropwise condensation heat transfer process optimisation on superhydrophobic surfaces using a multi-disciplinary approach
Dropwise condensation has superior heat transfer efficiency than filmwise condensation; however condensate evacuation from the surface still remains a significant technological challenge. The process of droplets jumping, against adhesive forces, from a solid surface upon coalescence has been studied using both experimental and Computational Fluid Dynamics (CFD) analysis. Both Lattice Boltzmann (LBM) and Volume of Fluid (VOF) methods have been used to evaluate different kinematic conditions of coalescence inducing a jump velocity. In this paper, an optimisation framework for superhydrophobic surface designs is presented which uses experimentally verified high fidelity CFD analyses to identify optimal combinations of design features which maximise desirable characteristics such as the vertical velocity of the merged jumping droplet from the surface and energy efficiency. A Radial Basis Function (RBF)-based surrogate modelling approach using design of experiment (DOE) technique was used to establish near-optimal initial process parameters around which to focus the study. This multidisciplinary approach allows us to evaluate the jumping phenomenon for superhydrophobic surfaces for which several input parameters may be varied, so as to improve the heat transfer exchange rate on the surface during condensation. Reliable conditions were found to occur for droplets within initial radius range of r=20-40 μm and static contact angle θs~160º. Moreover, the jumping phenomenon was observed for droplets with initial radius of up to 500 μm. Lastly, our study also reveals that a critical contact angle for droplets to jump upon coalescence is θc~140º
Predictions of total and total reaction cross sections for nucleon-nucleus scattering up to 300 MeV
Total reaction cross sections are predicted for nucleons scattering from various nuclei. Projectile energies to 300 MeV are considered. So also are mass variations of those cross sections at selected energies. All predictions have been obtained from coordinate space optical potentials formed by full folding effective two-nucleon (NN) interactions with one body density matrix elements (OBDME) of the nuclear ground states. Good comparisons with data result when effective NN interactions defined by medium modification of free NN t matrices are used. Coupled with analyses of differential cross sections, these results are sensitive to details of the model ground states used to describe nuclei
Considerations for determining research priorities: learning cycles and impact pathways
Agricultural researchers identify and apply new science, novel approaches and innovations that could generate research breakthroughs and improve impacts to support the development of the agricultural sector. During the past few decades, there has been an expansion of the research agenda along the entire research-fordevelopment continuum, with farm- and policy-level implications. The goals and objectives of research have broadened from primarily food production to include sustainable resource management, equity, gender, health, and environmental concern
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