Next-to-next-leading order correction to 3-jet rate and event-shape distribution

The hadronic events from the e ⁺ e ⁻ annihilation data at the centre-of-mass energies ranging from 60 to 197 GeV were studied. The AMY and OPAL Collaborations offered a unique opportunity to test QCD by measuring the energy dependence of different observables. The coupling constant, α _s, was measured by two different methods: first by employing the three-jet observables. Combining all the data, the value of as at next-to-next leading order (NNLO) was determined to be 0.117 ± 0.004(hard) ± 0.006(theo). Secondly, from the event-shape distributions, the strong coupling constant, α _s, was extracted at NNLO and it’s evaluation was tested with the energy scale. The results were consistent with the running of α _s, expected from QCD predictions. Averaging over different observables, α _s was determined to be 0.115 ± 0.007(hard) ± 0.003(theo).     

Generalized Wall Functions for High-speed Separated Flows Over Adiabatic and Isothermal Walls

We present the extension of our wall-laws developed for low-speed flows to super-and hyper-sonic configurations. In particular, we are interested in flows over isothermal walls and in the modeling of heat transfer. We recall the main steps of the development:

?Obtaining generalized wall functions for low-speed fluids, valid for all y ⁺.

?Taking into account transversal effects in wall-laws.

?Accounting for the compressible feature of the flow on adiabatic walls without using information on the local boundary layer structure, for instance its thickness, but only using information available at the fictitious wall.

?Taking into account thermal effects on isothermal walls. In particular, the heat flux at the real wall is obtained by an a posteriori evaluation using information at the fictitious one.

?Only using information available on unstructured meshes and avoiding the information coming from a Cartesian hypothesis for the mesh in near-wall regions.

These ingredients are validated on hyper-sonic configurations on adiabatic and isothermal walls for expansion and compression ramps.     

ACTIVE CONTROL OF FLEXIBLE STRUCTURES USING PRINCIPAL COMPONENT ANALYSIS IN THE TIME DOMAIN

Principal component analysis is used to simplify the extraction of the natural frequencies and their corresponding orthonormal mode shapes directly from experimental data of unknown flexible structures. A control law is designed using a state-space modal model and is tested on different structures. The results are extremely encouraging and demonstrate successful implementation of the active control strategies. The controller actuator as well as the detection sensor locations are examined throughout the structure length.     

A Quantum Chemical Investigation on the Antioxidant Activity of Licoisoflavone Derivatives

In this paper,21 substituents with various electron donating and electron withdrawing characters were placed in the available positions of Licoisoflavone in order to study their effect on the three O–H bond dissociation enthalpies and ionisation potential via DFT/B3LYP method.Results show that the B-ring is more important than the A-ring from the BDE and IP point of view because the radical structure formed after hydrogen atom abstraction from the 4-OH group can be stabilized by the resonance between the three rings.The results show that intramolecular hydrogen bonding effects are able to considerably stabilize the parents and radicals.The NBO analysis results also confirmed the intramolecular hydrogen bond stabilization.The formation of strong intramolecular hydrogen bonds and suitable spin density distributions in several radicals result in low BDE and IP values.The calculated BDE and IP values have been correlated with Hammett constants.The found dependencies are suitably linear,which can be important for the synthesis of novel antioxidants based on Licoisoflavone.     

Calculation of energy spectrum of <Superscript>12</Superscript>C isotope with modified Yukawa potential by cluster models

In this paper, we have calculated the energy spectrum of ¹²C isotope in two-cluster models, 3 α cluster model and ⁸Be + α cluster model. We use the modified Yukawa potential for interaction between the clusters and solve the Schrödinger equation using Nikiforov–Uvarov method to calculate the energy spectrum. Then, we increase the accuracy by adding spin-orbit coupling and tensor force and solve them by perturbation theory in both models. Finally, the calculated results for both models are compared with each other and with the experimental data. The results show that the isotope ¹²C should be considered as a three- α cluster and the modified Yukawa potential is adaptable for cluster interactions.     

Vector wave diffraction pattern of slits masked by polarizing devices

Polarization property is important to the optical imaging system. It has recently been understood that the polarization properties of light can be fruitfully used for improving the characteristics of imaging system that includes polarizing devices. The vector wave imagery lends an additional degree of freedom that can be utilized for obtaining results that are unobtainable in scalar wave imagery. This calls for a systematic study of diffraction properties of different apertures using polarization-sensitive devices. In the present paper, we have studied the Fraunhofer diffraction pattern of slits masked by different kinds of polarizing devices which introduce a phase difference between the two orthogonal components of the incident beam.     

Minimal degrees of faithful quasi-permutation representations for direct products of p-groups

In [2], the algorithms of c(G), q(G) and p(G), the minimal degrees of faithful quasi-permutation and permutation representations of a finite group G are given. The main purpose of this paper is to consider the relationship between these minimal degrees of non-trivial p-groups H and K with the group H×K.     

Synthesis and Characterization of Amino-functionalized Meso-porous Silicate MCM-41 for Removal of Toxic Metal Ions

Amino-functionalized MCM-41 has been prepared by grafting amino containing functional groups onto mesoporous silicate MCM-41 and characterized by powder X-ray diffraction, N2 adsorption/desorption measurement, SEM, FT-IR, thermogravimetry and elemental analysis to confirm the ordered mesoporous structure and the functionalization of the amino groups. Sorption behavior for 18 metal ions on this sorbent has been studied and discussed.     

Next-to-next-to-leading order calculation of the strong coupling constant α s by using moments of event-shape variables

The next-to-next-to-leading order (NN’LO) quantum chromodynamics (QCD) correction to the first three moments of the four event-shape variables in electron–positron annihilation, the thrust, heavy jet mass, wide, and total jet broadening, is computed. It is observed that the NNLO correction gives a better agreement between the theory and the experimental data. Also, by using the above observables, the strong coupling constant (α _s) is determined and how much its value is affected by the NNLO correction is demonstrated. By combining the results for all variables at different centre-of-mass energies $\alpha_{\rm s} ({M_{Z^0}})=0.1248\pm 0.0009\left( {\exp\!.} \right)_{-0.0144}^{+0.0283} \left({\mbox{theo}.} \right)$ is obtained.