Quantum walk on distinguishable non-interacting many-particles and indistinguishable two-particle

We present an investigation of many-particle quantum walks in systems of non-interacting distinguishable particles. Along with a redistribution of the many-particle density profile we show that the collective evolution of the many-particle system resembles the single-particle quantum walk evolution when the number of steps is greater than the number of particles in the system. For non-uniform initial states we show that the quantum walks can be effectively used to separate the basis states of the particle in position space and grouping like state together. We also discuss a two-particle quantum walk on a two- dimensional lattice and demonstrate an evolution leading to the localization of both particles at the center of the lattice. Finally we discuss the outcome of a quantum walk of two indistinguishable particles interacting at some point during the evolution.Comment: 8 pages, 7 figures, To appear in special issue: "quantum walks" to be published in Quantum Information Processin

PETROLEUM REFINERY RESIDUALS AND WASTES MANAGEMENT -A REVIEW

Residuals and wastes are produced in crude oil refineries. Intermediate residuals are waterborne, airborne and solids. Waterborne residuals are treated by API separators. The reductionof H2Sand S02 to elemental sulfur is desirable in airborne residuals. US Environmental ProtectionAgency (EPA) has characterized hazardous wastes based on ignitability, corrosivity., r,eactivity or toxicity

Recent Trends in Production of Hydrogen from Biomass

Biomass is a potential source to accelerate realization of hydrogen as a major fuel of the future. In the present paper different routes of hydrogen production from biomass are discussed that includes direct production routes as well as conversion of storable intermediates formed during various processes. The direct routes mainly comprise thermal gasification, solar gasification and other direct processes. The intermediate products like syn gas, bio oil are converted to hydrogen. The co-production of hydrogen and methanol is an attractive option

CORROSION INHIBITION IN HYDROCARBON HANDLING SYSTEMS

Corrosion inhibitors are chemicals that react with a metallic surface or the corrosive environment to which metallic surface is exposed, giving the metal surface a certain level of protection. Most of the corrosion inhibitors, used in petroleum industry, are either inorganic or organic compounds depending on the type of corrosion problems faced by the specific system. The composition and structure of the organic corrosion inhibitors change according to the applications in the petroleum industry which vary from purely aqueous to hydrocarbon rich media. Present article highlights the utility of the corrosion inhibitors used during hydrocarbon handling which are either nitrogen containing organic compounds or their derivatives. Th~ action of specific corrosion inhibitors used in hydrocarbon handling systems has been explained on the basis of experimental work carried out in authors' laboratory. The emphasis has been laid on the crude oil characteristics, nitrogen containing organic corrosion inhibitors, hydrophobic interaction during inhibition and the dependence of the inhibitor performance on the type of the test method used for its evaluation. KEYWORDS: Corrosion Inhibition, Hydrocarbon Handling System

Naphthenic Acid Corrosion in Petroleum Refineries

Present review article aims to highlight corrosion problems in refinery processing environment due to low molecular weight carboxylic acids commonly known as naphthenic acids. Various components like vacuum unit distillation column, pumps, transfer lines and exchangers are affected due to naphthenic acid corrosion in refinery environment. Naphthenic acids cause more severe corrosion in vapor phase when compared to liquid phase and velocity has an effect on the corrosion rate through wall shear stress. Corrosion intensity also depends on the physical state of the acids present in the operating system. Suitable corrosion monitoring is invariably required to check the effectiveness of any corrosion control measure. Various modern instrumental techniques for the determination of the nature of the naphthenic acids present can provide vital information such as acids' sizes and composition, which may be used in the battle against corrosion and also used to fingerprint samples from different oil fields. Different corrosion preventive measures like blending, material up gradation, use of resistant alloys and chemical treatment using corrosion inhibitors have been taken into account while discussing the problem in detail. Keywords: Corrosion, Naphthenic acids and Refinery

THERMODYNAMIC PROPERTIES OF OXYGEN COMPOUNDS I. VINYL ACETATE

A complete vibrational assignment is made and ideal gas thermodynamic properties of vinyl acetate have been reported from 100-1500 K. Internal rotational contributions have been calculated using Pitzer and Gwinn's tables

Biomass-based energy fuel through biochemical routes: A review

Energy demand is increasing continuously due to rapid growth in population and industrialization development. The development of energy sources is not keeping pace with spiraling consumption. Even developed countries are not able to compensate even after increasing the energy production multifold. The major energy demand is provided from the conventional energy sources such as coal, oil, natural gas, etc. Two major problems, which every country is facing with these conventional fuels, are depletion of fossil fuels and deterioration of environment. The present review article aims to highlight various biochemical processes for conversion of biomass into biological hydrogen gas and ethanol. The present discussion focuses on hydrogen production through various routes viz. fermentative, photosynthesis and biological water gas shift reaction. In addition, emphasis has been laid on ethanol as biomass-based energy fuel. The discussion has been focused on the technology for ethanol production from various biomass sources such as molasses, lignocellulosic feedstock and starch. Various biochemical processes and their major steps involved during the ethanol production from biomass have been discussed in detail. Keywords: Hydrogen; Ethanol; Biomass; Biochemica