IOSR-JAP   Volume-3 ~ Issue-2 ~ March–April 2013

Paper Type	:	Research Paper
Title	:	Binding Energy Of A Donor In A Spherical Quantum Dot , GaAs
Country	:	India
Authors	:	S.R.Chitra., M.Sc., M.Phil., PGDCA.,[Ph.D].,
	:	10.9790/4861-0320105

Abstract: The binding energy of a donor in spherical quantum dots (QDs) is calculated, using a variational approach within the effective mass approximation. The binding energy is computed for GaAs QD as a function of the dot size for different impurity positions, and also as a function of the impurity position for different dot sizes. The results of mine show that when the impurity binding energy increases with the reduction in the dot dimension. The binding energy is also found to depend on the location of the impurity, and the same is the maximum for the on-center impurity. Also I found that the value of the polarizability obtained is several orders higher than the hydrogen atom value.

Keywords: Spherical quantum dot, Donor binding energy, Impurity state, Parabolic confinementQuantum dots , quantum wells gallium arsenide, III-V semiconductors, impurity states, effective mass, donor Binding , Semiconductor compounds

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Paper Type	:	Research Paper
Title	:	Infinite dimensions and the creation of Universe
Country	:	India
Authors	:	Aman Mishra
	:	10.9790/4861-0320610

Abstract: Science and technology has unraveled many mysteries of our universe but the biggest question of all times still remains an enigma that how our universe came to an existence and what was there before the existence of our universe. A correct explanation will not only let us to understand our birth but will also provide insight to intriguing questions like will our universe have an end and if not how it is going to be. This might give a new outlook to seeing our universe and provide us with the theory of everything. .This paper talks about what was before the big bang, how extra dimensions can be seen, where cosmic censorship can be violated, the constraint energy of the universe, the negative energy and its role in our universe.

Keywords: negative energy, naked singularity, extra dimensions, particle decay, particle accelerator, large hadron collider (LHC) PACS numbers: 98.80.-k; 05.70.-a; 25.75.Gz; 25.75.Dw; 02.40.Xx; 04.20.-q

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Paper Type	:	Research Paper
Title	:	Experimental Studies on Corona Discharge Ionization
Country	:	India
Authors	:	V. S. Sawant
	:	10.9790/4861-0321115

Abstract: This study investigates the possibility of corona discharge ionization technique for reduction of fog. For corona discharge ionization a high voltage power supply is designed and developed indigenously. The high output voltage is developed by using isolation transformer, autotransformer, and high voltage neon transformer and it is converted into DC voltage by using Wheatstone bridge circuit and high voltage capacitor. Formation of negative corona, positive corona and voltage-current characteristics of corona ionization was studied. By selecting -9 kV voltages to discharge electrode, the performance of this circuit was tested for removal of fog, Fog was generated by using ultrasonic water fogger collected in closed glass container. Various runs were carried out. The light intensity was measured for each run as a function of time, in presence and absence of the discharge. After continuous operation of device for 6 minutes, 90% to 95% of the aerosols were removed from container in addition to the natural decay effect.

Keywords: Corona discharge, High voltage, Ionization of Air, Positive Corona, Negative Corona

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