60 research outputs found
Quantum-dynamical Modeling of the Rydberg to Valence Excited-State Internal Conversion in Cyclobutanone and Cyclopentanone
In this paper we present 4-state, 5-dimensional Vibronic Coupling Hamiltonians for cyclobutanone and cyclopentanone. Wave packet calculations using these Hamiltonians reveal that for cyclobutanone the (n,3s) to (n,π*) internal conversion involves direct motion in nuclear modes coupling the two states leading to fast population transfer. For cyclopentanone, internal vibrational energy redistribution is a bottleneck for activating reactive nuclear modes leading to slower population transfer
Success or failure of primary second/foreign language programmes in Asia: What do the data tell us?
Primary school second/foreign language (SL/FL) programmes in Asia, as well as in other parts of the world, are becoming more common, with many targeting English as the SL or FL. The pressures for such English language programmes come from top-down notions that in a globalised world English is required for societies to be competitive, especially with Asian neighbours, and bottom-up pressures from parents who see English as the key to educational success for their children. In many polities, these forces have resulted in support for policies that introduce early primary school English teaching curricula for all students and have led to parents spending large sums of money on private tutoring or out-of-school tuition. This study reviews the results of nine language planning studies from the Asian region that set out to examine questions such as 'Is this trend towards early primary SL or FL education (mainly English) realistic or is it unattainable and a waste of resources? Do children really benefit from these programmes? What needs to be done to foster learners' success?' These issues are viewed from a language planning and policy perspective through an examination of the language-in-education policy types required for the development of successful programmes. The policies of a number of Asian countries are used as case studies to illustrate this issue
Ultrafast nonlinear dynamics in thin GaN films studied by femtosecond digital holography
We studied the nonlinear propagation dynamics of intense 300 fs infrared pulses in thin GaN films by use of pulsed digital holography technique with 25 fs temporal resolution
Ultraviolet-resonance femtosecond stimulated Raman study of the initial events in photoreceptor chromophore
Resonant Two-Photon Excitation Pathways During Retinal-Isomerization in Bacteriorhodopsin
Ultrafast structural and vibrational dynamics of the hydration shell around DNA
Two-dimensional infrared spectroscopy in the frequency range of OH- and NH stretch excitations serves for a direct mapping of hydration dynamics around DNA. A moderate slowing down of structural dynamics and resonant OH stretch energy transfer is observed in the DNA water shell compared to bulk water
Coherent nuclear wave packet dynamics of laurdan launched by intramolecular charge transfer
Coherent nuclear wave packets in the product state launched by the ultrafast intramolecular charge transfer are observed by time-resolved fluorescence with 40 fs time resolution. Direct information on reaction coordinates and structural changes can be obtained
B-side Electron Transfer in Bacterial Photosynthetic Reaction Centers Revealed by a Few-Cycle Pulse Laser
Photoinduced Coherent Spin Fluctuation in Primary Dynamics of Insulator to Metal Transition in Perovskite Cobalt Oxide
Coherent spin fluctuation was detected in the photoinduced Mott insulator-metal transition in perovskite cobalt oxide by using 3 optical-cycle infrared pulse. Such coherent spin fluctuation is driven by the perovskite distortion changing orbital gap
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