1,723 research outputs found
Transformation of 2,4, 6-Trinitrotoluene (TNT) by Immobilized and Resting Cells of Arthrobacter SP.
Arthrobacter sp. transformed 2,4,6-trinitrotoluene (TNT) into two isomeric monoaminodinitrotoluenes viz, 4-amino-2,6-dinitrotoluene (4-ADNT), 2-amino- 4,6 –dinitrotoluene (2-ADNT) and also 2,4- diamino-6- nitrotoluene (2,4-DANT) under aerobic resting cell conditions. Experiments were carried out at 30° C (±1°C) in phosphate buffer with 60 mg per liter TNT at a pH of 7.2 (±0.2). Complete transformation of TNT occurred within 36 hours, yielding a mixture of monoaminodinitrotoluenes and diaminonitrotoluene. The major component was found to be 4-ADNT. Under the same experimental conditions, transformations were studied using barium alginate immobilized cells of Arthrobacter sp. Appropriate controls were run simultaneously. In both the cases, reactions were monitored every six hours by thin-layer chromatography (TLC) and gas chromatography (GC). The products were identified by gas chromatography coupled with mass spectrometry (GC-MS). Immobilization of Arthrobacter sp. in barium alginate resulted in more efficient TNT transformations, which were complete in 24 hours. The immobilized cells could be utilized at least for eight cycles and a decrease in rate of transformation was observed with each cycle
Experimental Investigation and Numerical Optimization of Dual Evaporator Refrigerator
Improving energy efficiency and reducing the cost of the appliance simultaneously is a continuing challenge for refrigerator manufacturers. While conventional system configuration is based on a single evaporator vapor compression cycle, there are several other system configurations that can offer benefits over it. For example, a dual evaporator (one evaporator for freshfood and one for freezer) offers several benefits such as increased efficiency, isolation of odors, and higher humidity levels in the freshfood compartment. Engineers typically use extensive experimentation to optimize the system. This approach takes significant time and resources. Although optimization studies exists for a conventional single evaporator cycle, studies for dual evaporator cycle optimization are limited. Most manufacturers do not explore complex architecture due to time consuming, labor intensive and expensive development procedures. This study presents experimental results obtained from a prototype dual evaporator refrigerator. Further, this study presents a physics-based model and a multi-objective optimization methodology that demonstrates how engineers can optimize a refrigeration system by considering multiple objectives simultaneously. The study presents example optimization results for simultaneously minimizing cost and maximizing performance within a specified design space. Optimization of the novel design uses a genetic algorithm-based optimizer in conjunction with a response surface based metamodel. Using optimization techniques, we can arrive at lowest cost design relatively quickly as shown in the analysis. More work needs to be done to validate optimized solutions as well as alternate methods to improve temperature control
Numerical study of resistivity of model disordered three-dimensional metals
We calculate the zero-temperature resistivity of model 3-dimensional
disordered metals described by tight-binding Hamiltonians. Two different
mechanisms of disorder are considered: diagonal and off-diagonal. The
non-equilibrium Green function formalism provides a Landauer-type formula for
the conductance of arbitrary mesoscopic systems. We use this formula to
calculate the resistance of finite-size disordered samples of different
lengths. The resistance averaged over disorder configurations is linear in
sample length and resistivity is found from the coefficient of proportionality.
Two structures are considered: (1) a simple cubic lattice with one s-orbital
per site, (2) a simple cubic lattice with two d-orbitals. For small values of
the disorder strength, our results agree with those obtained from the Boltzmann
equation. Large off-diagonal disorder causes the resistivity to saturate,
whereas increasing diagonal disorder causes the resistivity to increase faster
than the Boltzmann result. The crossover toward localization starts when the
Boltzmann mean free path relative to the lattice constant has a value between
0.5 and 2.0 and is strongly model dependent.Comment: 4 pages, 5 figure
Interacting entropy-corrected new agegraphic dark energy in Brans-Dicke cosmology
Motivated by a recent work of one of us [1], we extend it by using quantum
(or entropy) corrected new agegraphic dark energy in the Brans-Dicke cosmology.
The correction terms are motivated from the loop quantum gravity which is one
of the competitive theories of quantum gravity. Taking the non-flat background
spacetime along with the conformal age of the universe as the length scale, we
derive the dynamical equation of state of dark energy and the deceleration
parameter. An important consequence of this study is the phantom divide
scenario with entropy-corrected new agegraphic dark energy. Moreover, we assume
a system of dark matter, radiation and dark energy, while the later interacts
only with dark matter. We obtain some essential expressions related with dark
energy dynamics. The cosmic coincidence problem is also resolved in our model.Comment: 16 pages, no figure, accepted for publication in Gen. Relativ. Gra
Power-law entropy-corrected HDE and NADE in Brans-Dicke cosmology
Considering the power-law corrections to the black hole entropy, which appear
in dealing with the entanglement of quantum fields inside and outside the
horizon, the holographic energy density is modified accordingly. In this paper
we study the power-law entropy-corrected holographic dark energy in the
framework of Brans-Dicke theory. We investigate the cosmological implications
of this model in detail. We also perform the study for the new agegraphic dark
energy model and calculate some relevant cosmological parameters and their
evolution. {As a result we find that this model can provide the present cosmic
acceleration and even the equation of state parameter of this model can cross
the phantom line provided the model parameters are chosen suitably}.Comment: 14 pages, 2 figure, accepted by IJT
The Development of control system via Brain Computer Interface (BCI) - Functional Electrical Stimulation (FES) for paraplegic subject
Brain is known to be one of the powerful systems in human body because of its ability to give command and communicate throughout the body. The spinal cord is the pathway for impulses from the brain to the body as well as from the body to the brain. However, the bounty of this pathway could be lost due to spinal cord injury (SCI) and that results in a loss of function especially mobility. A combination of Brain Computer Interface (BCI) and Functional Electrical Stimulation (FES) is among one of the technique to regain the mobility function of human body which will be the focused area of this research. In this study, Electroencephalography (EEG) system will be used to capture the brain signal which will then drive the FES. A paraplegic subject will be involved in this study. The subject will be required to move the knee joint with involvement few muscle contraction. Overall, in this paper the combination of BCI-FES methods for development of rehabilitation system will be proposed. From this preliminary study, it can be summarized that the combination between BCI and FES potentially would provide a better rehabilitation system for SCI patient in comparison to the conventional FES system
Correlations of Heavy Quarks Produced at Large Hadron Collider
We study the correlations of heavy quarks produced in relativistic heavy ion
collisions and find them to be quite sensitive to the effects of the medium and
the production mechanisms. In order to put this on a quantitative footing, as a
first step, we analyze the azimuthal, transverse momentum, and rapidity
correlations of heavy quark-anti quark () pairs in
collisions at (). This sets the stage for the
identification and study of medium modification of similar correlations in
relativistic collision of heavy nuclei at the Large Hadron Collider. Next we
study the additional production of charm quarks in heavy ion collisions due to
multiple scatterings, {\it viz.}, jet-jet collisions, jet-thermal collisions,
and thermal interactions. We find that these give rise to azimuthal
correlations which are quite different from those arising from prompt initial
production at leading order and at next to leading order.Comment: 26 pages, 15 figures. Three new figures added, comparison to
experimental data included, abstract and discussion expande
Notes on dark energy interacting with dark matter and unparticle in loop quantum cosmology
We investigate the behavior of dark energy interacting with dark matter and
unparticle in the framework of loop quantum cosmology. In four toy models, we
study the interaction between the cosmic components by choosing different
coupling functions representing the interaction. We found that there are only
two attractor solutions namely dark energy dominated and dark matter dominated
Universe. The other two models are unstable, as they predict either a dark
energy filled Universe or one completely devoid of it.Comment: 9 pages, 10 figures. v2: Minor revisions, matches published versio
R-Norm Information Measure with Applications in Multi Criteria Decision Making Technique under Intuitionistic Fuzzy Set Environment
The main aim of this research article is to define a new information measure for quantifying fuzziness in the intuitionistic fuzzy set environment. For this purpose, we present R-norm intuitionistic fuzzy measure that quantifies the amount of vagueness or fuzziness of a particular fuzzy set. We prove that this measure is a valid measure of intuitionistic fuzzy entropy by making it satisfy essential properties. Also, some mathematical properties are used to check the validation of the measure. In the end, a practical example of decision-making is illustrated in terms of Multi Criteria Decision Making problem that presents the application of the proposed measure
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