Investigation of Dynamical Parameters of Exciton Confined in CdS Spherical Quantum Dots with a B—Spline Technique

Exciton energies as a function of radii of quantum dots in the range of 5–35 ? are calculated based on effective mass approximation model with the B-spline technique and compared with experimental and other theoretical data for the CdS dots. This method leads to accurate and fast convergent exciton energy, which are in good agreement with experimental data in the whole confinement regime. The effect of penetration of wave function from the inside to the outside of the dots and the effect of dielectric constants are taken into account. The magnitudes of dynamical parameters are discussed. It is found that the different materials surrounding the CdS quantum dot affect not only the potential energy and Coulomb interaction energy of the system, but also the effective masses. The comparison shows that the effective mass approximation model can describe very well the quantum size effects observed experimentally on the exciton ground state energy.

Combined effect of US/PFS on the black liquor of making paper

The reed pulping black liquor is used as a sample. Researches of (1) combined effect of ultrasound(US)/polyferric sulphate(PFS)/hydrogen peroxide(H 2O 2); (2) effects of the horn tip areas; (3) effect of dose of PFS were carried. Extrapolation of these experiments indicated treatment results are possibly related to complex chemical compositions in the reed pulping black liquor.

Sonolysis and mineralization of pentachlorophenol by means of varying parameters

Degradation effect of organic pollutant on pentachlorophenol(PCP) is researched by ultrasound. PCP is treated by low frequency(16 kHz) and high frequency(800±1 kHz), and bi frequency. The results of investigation on the ultrasonic destruction of PCP showed that the rate of PCP degradation at the same conditions is the highest at bi frequency, and the lowest at 16 kHz. In the presence of Fenton type reagent the degradation rate of PCP is the highest at bi frequency(20 93 times) as compared to the stirring system. This ratio is 4 91 and 1 06 at 800 kHz and 16 kHz, respectively. The studies showed the bi frequency is an effective method for pollutants degradation, but it is need make further study. Taking 800 kHz for example, under the same conditions, the smaller pH of the solution, the higher is the reaction rate. A similar situation applied to TOC, but the TOC removal lags behind degradation of PCP. This indicated the PCP is not completely mineralized. The ultrasound is somewhat enhanced for degradation of PCP and mineralization with only addition of CuSO 4, but the combination of ultrasound and Fenton type reagent is effective method for PCP degradation and mineralization. The rate of PCP degradation and TOC removal appeared to follow pseudo first order reaction kinetic law.

ON CHOVER'S LIL FOR THE WEIGHTED SUMS OF STABLE RANDOM VARIABLES

Let {Xn,n ≥ 1} be a sequence of α-stable random variables(0 < α < 2), {ani,1 ≤ i≤ n, n≥1} be an array of constant real numbers. Under some restriction of {ani,1 ≤ i ≤ n,n≥1}, the authors discuss the integral test for the weighted partial sums {Σi=1naniXi,n ≥ 1}, and obtain the Chover's laws of iterated logarithm(LIL) as corollaries.

Quantum Key Distribution Scheme Based on Dense Encoding in Entangled States

A quantum key distribution protocol, based on the quantum dense encoding in entangled states, is presented. In this protocol, we introduce an encoding process to encode two classical bits information into one of the four one-qubit unitary operations implemented by Alice and the Bell states measurement implemented by Bob in stead of direct measuring the previously shared Einstein-Podolsky-Rosen pairs by both of the distant parties, Alice and Bob.Considering the practical application we can get the conclusion that our protocol has some advantages. It not only simplifies the measurement which may induce potential errors, but also improves the effectively transmitted rate of the generated qubits by the raw key. Here we also discuss eavesdropping attacks against the scheme and the channel loss.

Reestablishment of an Unknown State and Its Orthogonal Complement State with Assistance

In this paper, we propose a protocol where one can realize reestablishment of an unknown state and its orthogonal complement state with a certain probability. In the first stage of the protocol, teleportation is performed between Alice (a sender) and Bob (a receiver) through a nonmaximally entangled quantum channel. In the process of teleportation, Alice performs nonmaximally entangled state measurement. In the second stage of the protocol, Victor (a state preparer) disentangles leftover nonmaximally entangled states by a single-particle measurement. With the assistance of Victor Alice can reestablish the original state or produce its orthogonal state.

Calculations of Electron Structure of Endohedrally Confined Helium Atom with B—Spline Type Functions

The B-spline basis set method is used to study the properties of helium confined endohedrally at thegeometrical centre of a fullerene. The boundary conditions of the wavefunctions can be simply satisfied with thismethod. From our results, the phenomenon of 'mirror collapse' is found in the case of confining helium. The interestingbehaviors of confining helium are also discussed.

Aggregation of Sodium Dodecyl Sulfonate in Poly-ethylene Glycol Aqueous Solutions Studied by Two-dimensional Nuclear Overhauser Enhancement Spectroscopy

Two-dimensional nuclear overhauser enhancement (2D NOESY)measurements show that sodium dodecyl sulfonate SDSN molecules co-aggregate with poly-ethylene glycol PEG in their aqueous solution at a concentration range of SDSN between the so-called co-aggregation concentration (cac) and the. Normal critical micellar concentration (cmc). SDSN micelles are formed when the cmc of SDSN is reached with PEG uniformly distributed in the interior.

A Simple Method to Generate Several Motional States in Two—Trapped Ions System

We propose a method to create several motional states simultaneously in two-trapped ions. It relies ontwo standing wave lasers illuminating homogeneously both ions. By tuning the frequencies of the two standing wavesto excite resonantly different sidebands of center-of-mass or breathing mode, several motional states, such as one- ortwo-mode squeezed states and their superpositions, and the beam-splitter output states, are generated.

Trace Distance of Remote State Preparation Through Noisy Channels

In this paper, we study remote state preparation (RSP) by w state through noisy channels. The trace distance is used to describe how close the original state is to the output state. Studies show the trace distance is a function of decohenrence rates and angles of the state to be prepared. At the same time, we investigate the influence of different types of noises on the trace distance and find the various types of noises have different degrees of influence on the trace distance for a definite qubit. We also study changes of the trace distance against polar and azimuthal angles.

Calculation of the hyperfine structure constants in ^(85)Rb and ^(133)Cs

For heavy atoms or ions, such as, Rb and Cs et al., relativistic effect must be considered in the calculation. In this paper, the relativistic many-body perturbation theory is used to solve the Dirac equation. And the zeroth-order hyperfine constants are evaluated with Dirac-Fock wave function. The finite basis sets of dirac equation are constructed by B-splines. With the finite basis sets the core polarization and the correlation diagrams are calculated. The hyperfine structure constants of the 5S1/2 and 6S<sub>1/2 states of 85Rb as well as the 6S1/2 and 7S<sub>1/2 states of 133Cs are evaluated.