Theoretical Studies

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Theoretical Studies on the Creation of Artificial Magnetic Monopoles

Theoretical Studies on the Creation of Artificial Magnetic Monopoles

In this study, we discuss the theoretical studies on the creation of artificial magnetic monopole, and new electromagnetic equations. Employing Lorentz transformation, radial electrostatic fields, and a stationary wave derived from a superconducting loop, we demonstrate the existence of a magnetic monopole whereby the divergence of the magnetic field is not zero. We develop a device wherein a condenser provides electrostatic fields along the radial direction to the superconducting loop and discuss the nodes of the resulting stationary wave along the superconducting loop. We employ the Lorentz transformation with respect to the vector and electrostatic potentials. Then, because the nodes have no three-dimensional vector potential and have zero magnetic field rotation, t he conserved energy is converted into new form that is associated with the magnetic field potential to yield the Lorentz transformation. As a result, we derived the relationship between the electric and the magnetic fields. This dependent relationship involves the exchange of the distribution characteristics of the static electric and static magnetic fields, and new electromagnetic equations of both electric and magnetic fields are obtained. We also analyzed the magnetic field from the magnetic monopole whose result assists the theory.

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Experimental and theoretical studies of transient molecules

Experimental and theoretical studies of transient molecules

There have been two theoretical studies of the infrared spectrum of nitrosamide; our own and that of Abou-Rachid and Pouchan [4.32 1. Recently Crowley has studied nitrosamide trapped in an inert matrix at 4.2 K by FTIR [4.42]. To assist in assigning his observed frequencies of matrix isolated H2 14N 14NO, H 2 15N 14NO and o 2 14N 14NO the ab-initio force constants were obtained directly from Gaussian 82 and were used to calculate the frequencies for the various isotopically substituted nitrosamides. These were then supplied to Crowley as requested. The scaled frequencies are given in Table 4-5 along with those of ref. [4.32] and Crowley's experimental data. The experimental assignments are those suggested by Crowley based mainly on comparison with the expected shifts upon isotope substitution, along with comparison of the experimental and theoretically predicted shifts of the analogous substitutions in the isoelectronic molecule formamide (NH2CHO). The scaled frequencies predicted from our HF/6-31 G planar structure should be more reliable than the scaled HF/4-31 G frequencies calculated by Abou-Rachid et al. A comparison of the scaled frequencies for the planar and non-planar structures with the experimental data is not sufficient to decide on the experimental geometry. Crowley however,

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Theoretical Studies of Cosmic Acceleration

Theoretical Studies of Cosmic Acceleration

The late universe is not the only place where the techniques of quantum field theory can address theoretical issues. In the very early universe we are faced with a number of ques- tions in inflation and some of its alternatives. The prevailing hypothesis for the origin of nearly scale-invariant temperature fluctuations observed in the cosmic microwave back- ground is that the early universe underwent a period of exponentially accelerated expansion called inflation (see [1] for a review) which stretched microscopic quantum fluctuations to macroscopic scales. In addition to explaining temperature anisotropies, inflation solves the horizon problem (why the universe appears uniform across apparently causually discon- nected regions) and the flatness problem (why the universe is spatially flat when curvature is expected to dominate at late times). It is important to understand if these successes are unique to inflation, and if there exist experimentally distinguishable alternatives.

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Theoretical Studies on InGaAs/InAlAs SAGCM Avalanche Photodiodes

Theoretical Studies on InGaAs/InAlAs SAGCM Avalanche Photodiodes

Theoretical Model with Consideration of Tunneling The above analysis model is about electric field dis- tribution in the device and based on the premise that ρ is the dopant ion in the depletion layer. If a sufficiently high electric field exists within the absorption layer, the local band bending may be suf- ficient to allow electrons to tunnel [34]. Therefore, electron tunneling can occur. From the tunneling schematic diagram in Fig. 4, when the absorption layer has a breakdown tunneling, the tunneling effect changes the charge density ρ, the positive charge in absorption increases, and the negative charge in the multiplication and charge layers increases. Thus, ρ is not equal to the dopant ion charge density in the

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Theoretical studies of doped carbon nanotube based materials

Theoretical studies of doped carbon nanotube based materials

In fact, D F T calculations for doped nanotubes have indeed been performed b ut have always been lim ited to a very small num ber of im purities, in order to m ain­ tain th e low concentration limit. For instance, studies of transition-m etal-doped nanotubes investigated their electronic and m agnetic properties both in isolation, and in nanotube bundles, but were restricted to a maximum of 3 im purities per un it cell [55]. D FT was again used to investigate the inclusion of Li'*^ ions inside nanotubes to assess w hether nanotubes could be used as lithium -based batteries; in this case only a single Li atom was considered. Such calculations may give indica­ tions of the effects th a t doping has on certain electronic proj)erties, b u t as far as th e conductance of a doped system is concerned, the lim itation to a small num ber of im purities can be misleading. M ultiple scattering events, which n atu rally reduce th e extended character of the electronic wave functions, cannot be fully taken into account if one is restricted to a very few im purities, which suggests th a t the effect of disorder on the tran sp o rt properties may be som ew hat underestim ated in those cases. Even when large unit cells are considered, which in principle allows calcula­ tions w ith an increased num ber of im purities, the results often bear little statistical significance, since many different configurations are needed to truly represent the statistic al ensemble of the disordered system.

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Theoretical studies on the encapsulation of Paracetamol in the a, b and g Cyclodextrins

Theoretical studies on the encapsulation of Paracetamol in the a, b and g Cyclodextrins

Cyclodextrins (CDs) are cyclic oligomers of alpha-D-glucose formed by the action of the glucosyltransferase enzyme on starch. The Cyclodextrins has a specific coupling of glucose monomers in cyclic manner giving a rigid conical molecular structure with a hydrophilic exterior and hollow hydrophobic interior of a specific volume. This internal cavity is capable of accommodating wide range of guest molecules including polar as well as non-polar aliphatic and aromatic compounds. The inside cavity of appropriate dimension is conducive to binding to various guest molecules to form an inclusion complexes. CDs’ chemistry has been reviewed many times through book- length treatment [17-21] and several shorter and more specialized articles [22-42]. There exist a significant number of computational studies over the past fifteen years that have been led to a deeper understanding of the structure, dynamics and chemical behavior of CDs’. Two excellent review articles covering theoretical aspects of CDs and their inclusion-occlusion complexes have been published [43-44]. The last article covers up to 1998, and since then a meaningful number of computational studies have appeared further describing the detailed, atomic level behavior of these molecules.

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Theoretical Studies of Heavy Ion Collisions via Holography

Theoretical Studies of Heavy Ion Collisions via Holography

Experimental studies of the collisions of heavy nuclei at relativistic energies have estab- lished the existence of the quark-gluon plasma (QGP) – a state of hot dense nuclear matter, in which quarks and gluons are not bound into hadrons. This state is characterized by the tem- perature T and chemical potential µ. With a decrease of chemical potential and temperature the matter goes to the confinement phase and QCD phase transition at T = T (µ) is expected.

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Theoretical studies of reactions involving ion-neutral complexes

Theoretical studies of reactions involving ion-neutral complexes

When the ions [PhCHCH 2 CH 3]+ (3) and [PhCH 2 C H C H 3]+ (5) are formed directly, they are likely to have less internal energy than those formed by isomerization from [PhC(CH3)2]+ (1). It would therefore not be surprising if fragmentation behavior differing from 1 was observed. There is some disagreement concerning deuterium-label exchange in 3 and 5 . One study did not observe any deuterium-label exchange with the ring in the 2,4,6-trideuterated analogue of 5, 5 while another study found that a reasonable amount of exchange with the ring occurs in both the 2- and 4-deuterated analogues of 3.6 Since 3 and 5 can rapidly interconvert at the energies relevant to ethylene loss (Figures 5.2 and 5.3), we would expect similar behavior from these isomers. A pathway that could possibly allow exchange with the ring to occur is isomerization of 5 to [2H+- PhC H 2 C H CH 2]+ (10). However, the energy o f the transition structure for this process (187 kJ mol-1) is above the dissociation threshold for ethylene loss (Figure 5.5) so we would not expect this to occur at any significant rate for metastable ions. Although it is possible that there are lower-energy pathways for this exchange, the present results are consistent with the occurrence of little or no deuterium exchange with the ring. Significant deuterium exchange within the side chain was observed in both studies ,5’6 the mechanism for this being exactly analogous to that discussed for [PhC(CH3)2]+ (1) above.

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Theoretical studies of steroid hormones and related compounds

Theoretical studies of steroid hormones and related compounds

In biological complexes, the electrostatic interaction is generally the most important, which means that variations in the total interaction energy are similar to those in the electrostatic binding energy. Ees may not be the largest term in evaluating the interactions at short range, but at medium to large separations of the molecules forming a complex, it is the dominant term, and although it may not have the largest magnitude, variations in Ees are responsible for the greatest effect upon the total binding energy, AE. Hence, it will determine how the substituents of the complex will orient with respect to one another. The remaining terms in the expansion normally only come into play at very close range in most biological studies, by which time the geometry of the complex will already be established. The tight - fitting nature of enzyme active sites and protein receptors means that at small separations of the two molecules, there can be little re-orientation of the complex.

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Theoretical and experimental studies of (In,Ga)As/GaP quantum dots

Theoretical and experimental studies of (In,Ga)As/GaP quantum dots

Quantum dot (QD) lasers grown on GaAs or InP sub- strate display lower threshold currents due to the 0D density of states when compared with QW lasers on the same substrates [9]. (In,Ga)P QDs grown on GaP sub- strate have already been studied, and room temperature electroluminescence has been obtained [10]. However, theoretical studies have shown that the electronic band lineups correspond to a borderline case between type I and type II [11]. The (In,Ga)As(N)/GaP QDs system has recently attracted much attention. Fukami et al. [12] have claimed that the transparency window of silicon may be reached with InGaAsN/GaP QDs when In com- position is 50% to approximately 60% and N compos- ition is 1% to approximately 2%. In the following, InGaAs/GaP QDs are studied as a step toward InGaAsN/GaP QDs system. Both room-temperature photoluminescence (PL) [13] and electroluminescence

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Theoretical and experimental studies of supercritical flow over baffles.

Theoretical and experimental studies of supercritical flow over baffles.

In his first paper (19) presented in 1965, he studied flow over a vertical sill in an open channel. He concluded that such flow can be concisely described by a set of five dimensionless variables. He also studied the force on the sill, where he related the coefficient of drag as a function of the Froude number, defined dimensionless variable of the flow and the ratio of downstream depth to the initial depth. Rand found that the drag coefficient varies from close to zero to close to 0.6, which compares well with Rajaratnam Cl?) studies oii the forced hydraulic jump.

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An overview of theoretical and empirical studies on deforestation

An overview of theoretical and empirical studies on deforestation

   Several recent studies apply forest transition theory to analyze land use or forest cover changes in different scales. At sub national level, Yeo & Huang (2013) explores a long-term pattern of forest transition in Mississippi and finds the presence of a repeated cycle of forest transition in this area. At national level, this approach is a focus of some studies, including Hostert et al. (2011) and Bae et al. (2012). The former study was conducted for the Soviet context, which experiences two different disturbances - political change and nuclear hazard. The authors find that effects of socio-politic-economic disturbances (political change) are tremendously as significant as the disturbance of technology (nuclear hazard). By analyzing the case of the development of urban forest in South Korea, a high economic growth country, the latter study finds that government policy can play an important role to transform land cover towards a higher forest cover. At regional level, a study by Munteanu et al. (2014) show how the shifts of socio-demographic and institutional factors can drive the pattern of forest transition in Carpathian region (Eastern and Central Europe). In the global level, by exploring across country data during 1990-2010, Köthke et al. (2013) confirm that global forest transition has been taking place at global level, finding a uniform pattern of forest decline.

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Theoretical and Experimental Studies of Vibrational Spectra of Nicotinic Acid

Theoretical and Experimental Studies of Vibrational Spectra of Nicotinic Acid

In the present work Raman and FTIR spectra of nicotinic acid have been analyzed using ab-initio and DFT calculations. The optimized geometries, harmonic vibrational wave number, structural parameters and intensities of the nicotinic acid have been calculated using MP2/6-311++G(d,p), B3LYP/6-311++G(d,p), B3PW91/6- 311++G(d,p), X3LYP/6-311++G(d,p) level of theories. Vibrational assignments have been made and calculated DFT frequencies and intensities of nicotinic acid are found to be in better agreement with corresponding experimental values in comparison to previous results. Selected experimental bands were assigned based on scaled theoretical wave numbers.

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Dual Sprocket in Two Wheeler (Theoretical and Experimental Studies)

Dual Sprocket in Two Wheeler (Theoretical and Experimental Studies)

We are designing the prototype with some safe design factors as calculated in the theoretical analysis. We are further consider this for the development of our project. We are trying to improve the project. We are in the plan to implement this concept with toggling mechanism. When we need high speed, in such cases we are using the larger driving and smaller driven drive to obtain our requirement. When we need high torque, the chain drive 1 is used for the transmission ie., smaller driving and larger driven drive. In addition to this modifications we are planned to implement some modifications in the gear box according to the drives. These are the significant modifications planned for the development of the project.

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Different Theoretical Approaches about European Studies

Different Theoretical Approaches about European Studies

First we have followed the literature that refers to the definitions of the European studies, thus making the corresponding conceptual boundaries since the beginning. Today we are confronted with concepts such as European Studies, European Union studies, European integration studies, as we have mentioned above. The debate on the used terminology is varied. Michael Smith from Queen's University of Belfast, UK, believes that European Union studies (Smith: 2003: 3) are the centre of the European Studies. On the other hand, Chris Rumford & Philomena Murray (Rumford, Murray: 2003: 86), state that European Union studies are actually European integration studies. If the studies about the European integration aim at the analysis of the phenomena related to the common market and, consequently, all the other phenomena connected, the European Union studies are more than an analysis of the market. Those represent a social model as well (Rumford, Murray, 2003: 88; Delanty, 1998: 3). The European Union can be just a framework for globalisation, anchored in solidarity and sustainability (European Council, 2001). On the other hand, the topic of multilevel governance started to be more and more present in the European Studies, and particularly since the debate around the governance took consistency (Hooghe, Marks, 2001). The model of multilevel governance permitted to detach the European Union studies from the European integration studies (Murray, 2000), because the European Union studies allow the development of other kind of approaches like: studies about regional policy, studies about the relation between globalization and European Union, studies about social policy, etc.

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Confused about theoretical sampling? Engaging theoretical sampling in diverse grounded theory studies

Confused about theoretical sampling? Engaging theoretical sampling in diverse grounded theory studies

For example, in the first exemplar, sampling from the ALS population-based register shifted from purposive sampling based on dimensions of the condition to theoretical sampling based on family context when ‘family support’ emerged as a theoretical construct shaping decisions about care. Theoretical sampling here shifted to being concerned with family context and away from concerns to do with the condition of ALS itself. Here a ‘flash of insight’ from broader existing scholarship prompted us to go conceptually beyond the empirical data to consider the role of context to generate data that allows for this insight to be tested against the empirical data. This reflects a concern to fill out a theoretical category that has the potential to explain why the phenomenon under inquiry presents as it does (rather than a concern to understand the breadth of the phenomenon under inquiry). We see here (as we do in the intergenerational friendship study) how theoretical sampling for contexts can capture and explain processes in data.

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