Experimental study of the dependence of beam current on injection magnetic field in 6.4 GHz ECR ion source

The ion current from an electron cyclotron resonance (ECR) heavy ion source depends on the confining axial and radial magnetic fields. Some efforts were made by earlier workers to investigate magnetic field scaling on the performance of the ECR source. In order to study the dependence of the ion current on the injection magnetic field in the 6.4 GHz ECR source, we have measured the current by varying the peak injection field and have inferred that the variation of the current is exponential up to our maximum design injection field of 7.5 kG. An attempt has been made to understand this exponential nature on the basis of ion confinement time.     

Job evaluation in fuzzy environment

Job evaluation helps in developing and maintaining a pay structure based on values of the jobs. The job evaluation problem may be treated as managerial decision-making problem with multiple objectives. The present paper deals with the evaluation of a job in fuzzy environment. Fuzzy mathematical model has been developed for the job evaluation and solved with a suitable technique. A sample case study has been considered and the relative worth of various levels of job factors have been calculated numerically along with the scores of the benchmark jobs. An effort has been made to optimize the decision by maximizing the min operator.     

Neutron scattering study of combustion-synthesized Ce<Subscript>1−<Emphasis Type="Italic">x</Emphasis></Subscript>Cu<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>O<Subscript>2−<Emphasis Type="Italic">x</Emphasis></Subscript>

Powder neutron diffraction and Hi-Q neutron diffraction data have been recorded and analysed in order to obtain the local and long range order of Cu in Cudoped CeO₂ with three doping levels of Cu. Rietveld method and MCGR techniques of data analysis for the two types of data reveal that the Cu ion is in the 2+ oxidation state and has a vacancy in its first coordination shell. These deductions from the data analysis fit well with the mechanism of catalysis we propose.     

Lax pair, cyclic basis, and a new integrable system

A direct approach to zero-curvature representation, as introduced by Marvan is applied to generate a new class of integrable equations by starting with the generic Lax operator (x-part) for a coupled set of nonlinear equations. The class of equation so obtained is more general than those usually obtained with the help of standard recursion operator. Finally some particular type of equations are identified by the special choice of the arbitrary functions occurring in the final solution of the time part of the Lax equation. The methodology is specially useful when the x-part of the Lax operator does not contain any spectral parameter.     

On PbS nanoparticles formed in the compartments of water/AOT/n-heptane microemulsion

Colloidal nanodispersion of lead sulfide has been prepared in the aqueous compartments of water/AOT/n-heptane. Compartmentalization has prevented growth and coagulation of particles in the dispersion. The uv–vis and fluorescence spectral measurements of the colloidal PbS dispersion were taken. Particle size has been determined by laser light scattering, transmission electron microscopy and absorption spectroscopy. The effects of temperature, ω (water/AOT mole ratio), [AOT], and [PbS] on the particle size have been examined. The nanodispersed particles in microemulsion capped with thiophenol and dodecanethiol were isolated and characterized by the TEM and FTIR methods.     

String Cosmology with Brans–Dicke Theory in Higher Dimensional Space-Time

We develop string cosmology in the presence ofa Brans–Dicke (BD) scalar field coupled toEinstein gravity for higher dimensional space-time.Solutions are obtained for the equation of state for thep-string, and physical situations arediscussed.     

Equivalence of the Generalized Vertical Block Linear Complementarity Problems and Linear Complementarity Problems

In this paper, generalization of a vertical block linear complementarity problem associated with two different types of matrices, one of which is a square matrix and the other is a vertical block matrix, is proposed. The necessary and sufficient conditions for the existence of the solution of the generalized vertical block linear complementarity problem is derived and the relationship between the solution set of the generalized vertical block linear complementarity problem and the linear complementarity problem is established. It is proved that the generalized vertical block linear complementarity problem has the P-property if and only if the vertical block linear complementarity problem has the P-property.     

Search for narrow-widtht-t resonances inp-p collisions at √s = 1.8 TeV

We present a preliminary result on a search for narrow-width resonances that decay intot-t pairs using 130 pb⁻¹ of lepton + jets data inp-p collisions at √s = 1.8 TeV. No significant deviation is observed from prediction of the standard model, and upper limits at 95% confidence on the product of the production cross-section and its branching fraction tot-t are presented for narrow-width resonances, as a function of resonance massMx. We also use these limits to exclude the existence of a leptophobic top-color particle,X, withM _x < 560 GeV/c² and width Γ_x = 0.012M _x .     

Two-dimensional electrical characterization of ultrashallow source/drain extensions for nanoscale MOSFETs

State-of-the-art semiconductor devices require accurate control of the full two-dimensional dopant distribution. In this work, we report results obtained on 2D electrical characterization of ultra shallow junctions in Si using off axis electron holography to study two-dimensional effects on diffusion. In particular, the effect of a nitride diffusion mask on lateral diffusion of phosphorous is discussed. Retardation of lateral diffusion of P under the nitride diffusion mask is observed and compared to the lateral diffusion of P under an oxide diffusion mask. The ultra shallow junctions for the study were fabricated by a rapid thermal diffusion process from heavily P doped spin-on-dopants into a heavily B doped Si substrate. These shallow junctions are needed for fabricating source/drain extensions in nanoscale MOSFETs. One-dimensional electrical characterization of the junction was carried out to determine the electrical junction depth and compared to the metallurgical junction depth from SIMS analysis.