1,280 research outputs found
Ultrafast dynamics of neutral superexcited Oxygen: A direct measurement of the competition between autoionization and predissociation
Using ultrafast extreme ultraviolet pulses, we performed a direct measurement
of the relaxation dynamics of neutral superexcited states corresponding to the
nl\sigma_g(c^4\Sigma_u^-) Rydberg series of O_2. An XUV attosecond pulse train
was used to create a temporally localized Rydberg wavepacket and the ensuing
electronic and nuclear dynamics were probed using a time-delayed femtosecond
near-infrared pulse. We investigated the competing predissociation and
autoionization mechanisms for superexcited molecules and found that
autoionization is dominant for the low n Rydberg states. We measured an
autoionization lifetime of 92+/-6 fs and 180+/-10 fs for (5s,4d)\sigma_g and
(6s,5d)\sigma_g Rydberg state groups respectively. We determine that the
disputed neutral dissociation lifetime for the \nu=0 vibrational level of the
Rydberg series is 1100+/-100fs.Comment: 5 pages, 4 figure
Analysis of Power Sector in India: A Structural Perspective
The inhibitors to growth in power sector were many—small and big but the main roadblock in the growth path was Government Policy, which made it difficult or rather impossible for a private player to enter. This further aggravated the problem that Indian entrepreneurs didn’t have enough knowledge and experience in developing power projects. To worsen the scenario, the SEBs and other Government Agencies became financially weak to propel any future expansion or growth in the sector. Electricity Act, 2003 was a major step in solving the above underlying problems of the power sector. A whole new system was evolved where private players were invited to be an active participant. The system demanded financial, political and other infrastructural growth—with major requirement in roads and communication. Some of the bold steps taken in the Act were moving generation and distribution out of ‘License Raj’ regime, opening access to national grid and demolishing the ‘Single Buyer’ model. The failure of the huge federal structure and the changing global scenario have forced Government to think of ways to revive this fundamental infrastructure sector. Two of the avenues that government can count on for future growth of this sector is “Midgets or Small Power Plants” and “CDM—Clean Development Mechanism” .Power Sector , India
Effects of submergence and test startup conditions on local scour by plane turbulent wall jets.
Experiments were carried out to study the interaction of plane turbulent wall jets with cohesionless soils during scour. The jet of water having a constant mean velocity of 1.16 m/s and thickness of 25.4 mm at the nozzle exit was set to initially flow tangentially along the sand bed with a median grain size of 2.15 mm. Both scour profile measurements and velocity measurements were obtained for a range of submergences, defined by the ratio of the tailwater depth to the nozzle opening. The results confirm the presence of two distinct types of flow fields, one that occurs at lower submergences and the other at higher submergences of the jet. At low submergences, laser Doppler anemometer measurements indicate that the jet flow is initially close to the bed and then flicks towards the water surface, whereas at the higher submergences, no such flicking movement was noticed. At higher submergences, however, the jet impingement point on the sand bed was highly unsteady. Low pass filtering of the velocity data give further details of these processes. It is seen that the movement of the impingement point for high submergences is more rapid with decreasing submergence. Furthermore, variations in scour and velocity profiles were noted in the mound region across the flume cross-section, and were found to be dependent on the level of submergence. In an effort to clarify some of the differences noted in the scour characteristics in earlier studies, the test startup conditions were varied. This includes an instantaneous, a gradual and a stepwise startup condition. The velocity measurements indicate that the flow gradually evolves to a state that is independent of the startup conditions. However, the scour profiles appear to be dependent on the startup conditions for a longer period of time.Dept. of Civil and Environmental Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2004 .D47. Source: Masters Abstracts International, Volume: 43-03, page: 0915. Advisers: Ram Balachandar; K. Mazurek. Thesis (M.A.Sc.)--University of Windsor (Canada), 2004
Effect of rejuvenation pruning on the growth, productivity and disease incidence in declining trees of pomegranate (Punica granatum L.) cv. Kandhari Kabuli
Pruning of fruit trees is an important aspect for the improvement of fruit quality and to minimize the pests and disease attack. Pruning was performed in the month of December in seven year old unpruned trees of Punica granatum cv. Knadhdri Kabuli having many interfering branching and a heavy infestation of bacterial blight orchard. The pruning treatments viz., T1: Retention of 15cm fruiting shoot length, T2: Retention of 30cm fruiting shoot length, T3: Retention of 45cm fruiting shoot length, T4: Retention of 60cm fruiting shoot length and T5: control (No heading back and no thinning) plant. The results of the present investigation revealed that among different pruning treatment, the best results in terms of shoot extension (56.34 cm), fruit size (Diameter 9.66 cm and Length 9.65 cm, fruit weight (278.50 g), marketable yield (10.25 kg) and fruit qualities were in fruits from T1 and T2 where retention of 15cm fruiting shoot length respectively and retention of 30cm fruiting shoot length were maintained. However, maximum fruit set (54.73%) was recorded in control, and it decreased with increasing pruning intensity. The pruning treatments also proved beneficial in controlling bacterial blight on fruit (12.86%) and leaf surface (26.60%) to some extent
On the Radio -chromatic Number of Paths
A radio -coloring of a graph is an assignment of positive integers (colors) to the vertices of such that for any two vertices and of , the difference between their colors is at least . The span of is . The radio -chromatic number of is . In this paper, in an attempt to prove a conjecture on the radio -chromatic number of path, we determine the radio -chromatic number of paths for if is odd and if is even
A transform of complementary aspects with applications to entropic uncertainty relations
Even though mutually unbiased bases and entropic uncertainty relations play
an important role in quantum cryptographic protocols they remain ill
understood. Here, we construct special sets of up to 2n+1 mutually unbiased
bases (MUBs) in dimension d=2^n which have particularly beautiful symmetry
properties derived from the Clifford algebra. More precisely, we show that
there exists a unitary transformation that cyclically permutes such bases. This
unitary can be understood as a generalization of the Fourier transform, which
exchanges two MUBs, to multiple complementary aspects. We proceed to prove a
lower bound for min-entropic entropic uncertainty relations for any set of
MUBs, and show that symmetry plays a central role in obtaining tight bounds.
For example, we obtain for the first time a tight bound for four MUBs in
dimension d=4, which is attained by an eigenstate of our complementarity
transform. Finally, we discuss the relation to other symmetries obtained by
transformations in discrete phase space, and note that the extrema of discrete
Wigner functions are directly related to min-entropic uncertainty relations for
MUBs.Comment: 16 pages, 2 figures, v2: published version, clarified ref [30
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