Sequential diblock copolymers composed of G and D-lactic acid residues were synthesized through a living ring-opening polymerization of t and D-lactide initiated by aluminium tris(2-propanolate). The composition of the block copolymers was varied by changing the reaction conditions and monomer over initiator ratio and confi ied by 'H NMR analysis, molecular weight determination and optical rota...

0022-2860/$ see front matter 2008 Elsevier B.V. A doi:10.1016/j.molstruc.2008.07.020 * Tel.: +49 551 201 2215; fax: +49 551 201 2202. E-mail address: [email protected] The absolute configurations of two estrogenic nonylphenols were determined in solution. Both nonylphenols, NP35 and NP112 could not be crystallized so that only solution methods are able to solve directly the question of abs...

Compensation of the temperature dependence of the Verdet constant in a polarimetric extrinsic Faraday sensor is of major importance for applying the magneto-optical effect to AC current measurements and magnetic field sensing. This paper presents a method for compensating the temperature effect on the Faraday rotation in a Bi12GeO20 crystal by sensing its optical activity effect on the polariza...

Effect of Site-disorder, Off-stoichiometry and Epitaxial Strain on the 1 Optical Properties of Magnetoelectric Gallium Ferrite 2 3 Amritendu Roy, Somdutta Mukherjee, Surajit Sarkar, Sushil Auluck, Rajendra 4 Prasad, Rajeev Gupta 4 and Ashish Garg 5 6 Department of Materials Science & Engineering, Indian Institute of Technology, 7 Kanpur-208016, India 8 Department of Physics, Indian Institute of...

Traditional methods of detecting chiral molecules, such as optical rotation are not suitable for miniaturization, since, the magnitude of the rotation of polarization scales down linearly with the optical path length of the device. Since the origin of optical activity is due to difference of refractive indices between the two circularly polarized states of light, it is possible to detect chiral...

Conformal invariance for bosonic strings in time-dependent backgrounds of graviton, dilaton and Kalb-Ramond field is obtained by imposing Weylbeta functions to be homogeneous in time, to all orders in α ′ . This construction is possible in any target space dimension, as a result of the non-trivial background configurations. The electromagnetic effects of the antisymmetric tensor field, when cou...

Optical pumping of an atomic sample with narrow-band light can create sub-Doppler features, known as Bennett structures, in the velocity distribution of state populations. In the presence of static magnetic or electric fields, the corresponding sub-Doppler features in the index of refraction can cause nonlinear optical rotation and induced ellipticity of resonant light propagating through the a...

We report on an experimental study of slow pulse propagation and polarization storage of light in an atomic vapour for pulse durations ranging from several μs to 100 μs, for non-zero magnetic fields, for temperatures ranging from 65 to 90 ◦C and for two different rubidium isotopes. The results confirm the presence of the electromagnetically induced transparency window as predicted by Lukin (199...

As part of a program to determine how small structural changes become manifest in the optical properties of crystals we used classical dipole–dipole interaction calculations to estimate the linear birefringence and optical rotatory power of the crystals Ph4X where X ~ C, Si, Ge, Sn, and Pb. Field induced effects including second harmonic generation, the electro-optic response and electrogyratio...

We have examined 8004 plates at the Harvard College Observatory Plate Collection searching for optical transient emission from the gamma-ray burst GRB 970228. This is the first archival search carried out so far for a gamma-ray burst with known transient optical emission. The total exposure time amounts to ∼ 1.1 yr. No convincing optical activity was found above 12.5 mag at the expected positio...