Formation of defect,oxygen vacancy creation,and shifting of phonon mode by Li3+ swift heavy ion irradiation on Zn1 − x Mn x O thin films

Journal of Solid State Electrochemistry - Thin films of pure, Mn-substituted ZnO were synthesized by dip coating technique and irradiated thin films by Li3+ swift heavy ions (SHIs) with fluence...     

Antimycobacterial 3-phenyl-4-thioxo-2H-1,3-benzoxazine-2(3H)-ones and 3-phenyl-2H-1,3-benzoxazine-2,4(3H)-dithiones substituted on phenyl and benzoxazine moiety in position 6

A series of forty-five derivatives of 3-phenyl-4-thioxo-2H-1,3-benzoxazine-2(3H)-ones and forty-five derivatives of 3-phenyl-2H-1,3-benzoxazine-2,4(3H)-dithiones was synthesised. The compounds exhibited in-vitro activity against Mycobacterium tuberculosis, M. kansasii (two strains), and M. avium. The most active derivatives were more active than isonicotinhydrazide (INH). The quantitative relationships between the structure and antimycobacterial activity were calculated. The activity against M. tuberculosis increased with the lipophilicity of the substituents.     

Search for CP violation in τ±→K(S)0π±ντ decays at Belle

We report on a search for CP violation in τ(±)→K(S)(0)π(±)ν(τ) decays using a data sample of 699 fb(-1) collected by the Belle experiment at the KEKB electron-positron asymmetric-energy collider. The CP asymmetry is measured in four bins of the invariant mass of the K(S)(0)π(±) system and found to be compatible with zero with a precision of O(10(-3)) in each mass bin. Limits for the CP violation parameter Im(η(S)) are given at the 90% confidence level. These limits are |Im(η(S))| < 0.026 or better, depending on the parametrization used to describe the hadronic form factors, and improve upon previous limits by 1 order of magnitude.     

History of the Irradiation Cross-Linking of Polyethylene

The formation of covalent C-C bonds or cross-links between the long chains in polyethylene (PE) by means of high energy irradiation was first deduced from changes in the stress-strain curves of the PE samples after irradiations in vacuo in the heavy water pile of the Argonne National Laboratory near Chicago in the academic year 1947-48. These cross-links can be produced in the solid sample at room temperature without change of shape of the sample. Such irradiated PE samples have a “memory effect” which has led to a large-scale application of the irradiation of PE to make heat shrinkable films and tubing.     

Hard-coupled model of local direct resistance heating of thin sheets

A monolithic model of local direct resistance heating of thin sheets is presented. The model respects all material nonlinearities of the system such as the temperature dependences of physical properties of individual parts of the system. Numerical computations are performed by a finite element method of higher order of accuracy and realized by our own codes Hermes2D and Agros2D. The methodology is illustrated by a typical example, whose results are discussed.     

Promoting Percent as a Proportion in Eighth‐Grade Mathematics

The literature provides many and varied suggestions for promoting conceptual understanding of percent and performing percent calculations. The diversity of ideas provides a wide selection but offers little clarity on the true nature of percent. From the premise that percent is fundamentally a proportion, this study incorporated a proportional approach for percent problem solving within an instructional program on percent. Classroom research with eighth‐grade students indicated that the method was readily adopted by students and helped them experience success in percent problem solving, with percent problem solving proficiency maintained over a delayed period. It is hypothesized that the method has the potential to promote students' conceptual knowledge of percent as a proportion and the multiplicative structure of percent, as well as to build proportional knowledge.     

Effect of substitution of Ce on superconducting properties of Bi1.7Pb0.3Sr2Ca2−x Ce x Cu3O10+δ system

We have investigated the superconducting properties of the Bi_1.7 Pb_0.3Sr₂Ca_2−xCe _x Cu₃O_10+δ system with x=0.00, 0.02, 0.04, 0.08 and 0.1 by X-ray diffraction and magnetic susceptibility. The substitution of Ce for Ca has been found to drastically change the superconducting properties of the system. X-ray diffraction studies on these compounds indicate decrease in the c-parameter with increased substitution of Ce at Ca site and volume fraction of high T _c (2 : 2 : 2 : 3) phase decreases and low T _c phase increases. The magnetic susceptibility of this compound shows that the diamagnetic on set superconducting transition temperature (onset) varies from 109 K to 51 K for x=0.00, 0.02, 0.04, 0.08 and 0.1. These results suggest the possible existence of Ce in a tetravalent state rather than a trivalent state in this system; that is, Ca²⁺ → Ce⁴⁺ replacement changes the hole carrier concentration. Hole filling is the cause of lowering T _c of the system.     

Estimation of the characteristic ratio of poly[2-(triphenylmethoxy)ethyl methacrylate] from hydrodynamic properties of its dilute solutions

Properties of poly[2-(triphenylmethoxy)ethyl methacrylate] (PTEMA) molecules in solutions (under O-conditions and in “good” solvents) were investigated by the light scattering, sedimentation, viscometric and by phase equilibria methods. The O-temperature (47°) was determined for the system mesitylene-PTEMA. Unusual correlations of hydrodynamic data with molecular weight are discussed and slight branching of polymer chains is accepted as a probable explanation. Data for mesitylene solutions under O-conditions are used to estimate the characteristic ratio of PTEMA molecules ($\text{R}{}_0{}^2\text{/nl}{}^2\text{= 19}$).