223 research outputs found
Fossil Fuel Consumption Trend and Global Warming Scenario: Energy Overview
Global warming is directly related to the consumption of fossil fuel and corresponding CO2 emission in the atmosphere. We have analyzed available data from various sources for energy consumptions, CO2 emissions, and Earth’s average atmospheric temperature during the period 1970 to 2018. We also analyzed the projected energy consumption data during 2018 to 2050. It is found that human industrial activities between 1970 and 2018 have consumed 385 Gtoe of fossil fuel and emitted1143 Gt of CO2 into the Earth’s atmosphere. As a result, the Earth’s average atmospheric temperature has increased 0.90? between 1970 and 2018. It is found that the projected world total fossil fuel consumption during 2018 to 2050 is 378 Gtoe. We estimate that this 378 Gtoe fossil fuel consumption emits 1122 Gt of CO2 into the Earth’s atmosphere resulting in about another1 °C increase in the Earth’s average atmospheric temperature. We suggest that the global warming is advancing more rapidly, and International communities, scientists and engineers must take appropriate rapid action to save the Earth from devastating consequences
Operator Equation of Motion in Phase Space and Path Integral Solution to Time-Dependent Systems Possessing Invariants : Application to Time-Dependent Harmonic Oscillator
A density functional theory-based chemical potential equalisation approach to molecular polarizability
The electron density changes in molecular systems in the presence of external electric fields are modeled for simplicity in terms of the induced charges and dipole moments at the individual atomic sites. A chemical potential equalisation scheme is proposed for the calculation of these quantities and hence the dipole polarizability within the framework of density functional theory based linear response theory. The resulting polarizability is expressed in terms of the contributions from individual atoms in the molecule. A few illustrative numerical calculations are shown to predict the molecular polarizabilities in good agreement with available results. The usefulness of the approach to the calculation of intermolecular interaction needed for computer simulation is highlighted
Theory of high bias Coulomb Blockade in ultrashort molecules
We point out that single electron charging effects such as Coulomb Blockade
(CB) and high-bias staircases play a crucial role in transport through single
ultrashort molecules. A treatment of Coulomb Blockade through a prototypical
molecule, benzene, is developed using a master-equation in its complete
many-electron Fock space, evaluated through exact diagonalization or full
Configuration Interaction (CI). This approach can explain a whole class of
non-trivial experimental features including vanishing zero bias conductances,
sharp current onsets followed by ohmic current rises, and gateable current
levels and conductance structures, most of which cannot be captured even
qualitatively within the traditional Self Consistent Field (SCF) approach
coupled with perturbative transport theories. By comparing the two approaches,
namely SCF and CB, in the limit of weak coupling to the electrode, we establish
that the inclusion of strong-correlations within the molecule becomes critical
in addressing the above experiments. Our approach includes
on-bridge-correlations fully, and is therefore well-suited for describing
transport through short molecules in the limit of weak coupling to electrodes.Comment: 19 pages 5 figure
Regulation of gastric acid secretion in situ by an endogenous activator protein: Studies with activator-specific antibody
Monospecific polyclonal antibody was raised against a homogenous preparation of endogenous activator protein (HAF) for the gastric H+,K+-ATPase system. Antibody was used to assess the regulatory role of the HAF in gastric acid secretion by isolated rabbit glands in situ.
Immunohistochemical studies revealed aredistribution of theHAFtowards discrete intracellular
zones following stimulation of the glands with histamine. The antibody, when inserted into the stimulated gastric glands by digitonin permeabilization, could effectively block the acid forming ability of the cells. The data offers, for the first time, some concrete in situ evidence for the role of the HAF as an intracellular regulator of gastric H+ transport .The manuscript was written (in the early 1990) soon after the data were collected, but never submitted to a journal with the hope of getting better gel picture and fluorescent micrograph which did not materialize due to unavoidable circumstances
Phytol-Derived Novel Isoprenoid Immunostimulants
This review describes the adjuvanticity of novel diterpenoids (synthetic phytol derivatives) compared to some commercially available adjuvants. The efficacy of the phytol-derived immunostimulants was evaluated in terms of their ability to activate innate immunity, amplify various antigen-specific immune responses, and engender immunological memory with no discernible adverse effects in both competent and immune-deficient mice. The profile that emerges out of these studies reveals that the phytol derivatives are excellent immunostimulants, superior to a number of commercial adjuvants in terms of long-term memory induction and activation of both innate and acquired immunity. Additionally, the phytol-derived compounds have no cumulative inflammatory or toxic effects even in immuno-compromised mice
Investigation of caving-in incident of MIG 21 aircraft
In an accident, the starboard (STBD) side of front fuselage was ‘caved in’ during ground run of the Mig-21. A post-incident inspection revealed vertical and horizontal cracking occurred at the edges of the additional air intake shutter (AAITS). The guard of the
AAITS was sucked in causing extensive damage to the aeroengine. However, port side fuselage remained un-affected. The chemical composition and evaluation of the mechanical properties of the alloy match with the Russian specification D16AT, D16ATB. It means that the duralumin alloy is in hardened and aged condition. Characterization of microstructure in optical, SEM and TEM illustrate more or less negligible variation for fresh and service exposed material. From the investigation it can be inferred, on the starboard side near some of the rivet holes at the edges of AAITS opening, primary cracks were formed owing to fretting fatigue. The structural non-uniformity of annular area on the starboard side with respect to port side raised the air pressure around the frame #5 and the skin ‘caved-in’. As engine demanded more air, under severe suction pressure, the skin containing micro-cracks
became unable to withstand the load and the guard was sucked in from outside towards the engine causing overload failure to the areas away from rivet hole and rest of the zones near the AAITS
- …