The geo-strategic importance of the Indian ocean in the context of the world oil crisis

The continuously growing demand of energy and the natural limitation of the energy resources makes today’s military, economic and diplomatic strategies of every nature to be shaped by the top priority objective: the uninterrupted access to energy resources. If nowadays 40% of the world’s consumer goods are transited across the Malacca Strait and 40% of the sea-transported oil transits the Hormuz Strait, the estimates made until 2030 indicate an increase of the energy needs by 45% globally, of which more than half will be due to India and China’s needs, implicitly leading to an intensification of the traffic across the Indian Ocean

Optical spectrum behaviour of a coupled laser system under chaotic synchronization conditions

Synchronization characteristics of two bidirectionally coupled semiconductor lasers, one operating in a chaotic regime with low-frequencyfluctuations and the other with free laser beam emission, were experimentally investigated. The chaotic synchronization regimes and opticalspectral behavior of the coupled system were analyzed with respect to the optical spectra emitted initially by the two uncoupled lasersoperated under the same feedback conditions. It was observed that the number of synchronization regimes that can be obtained and theirstability depend on the similarity of spectral structures of the uncoupled lasers emissions. The dominant active laser modes of the coupledsystem emission coincide with the laser modes of the one or both uncoupled laser emissions, depending on the operating synchronizationregime. We have associated changes in the optical spectrum of the coupled system with the synchronization regimes. The repartition ofpower between the active modes of a coupled system allows identification of the synchronization regime

Unresonant interaction of laser beams with microdroplets

The interaction of distilled water microdroplets (volumes of 3-4μl) with pulsed laser beams emitted at 532nm is described. At 532nm the distilled water absorption is very low and the interaction of a water bead with the laser radiation is dominated by unresonant phenomena. Following the collision of the laser beam with a microdroplet in suspended/ hanging/pendant position in air, deformations and mechanical vibrations of the droplets are produced. The conditions in which the droplets lose material as a consequence of the impact with laser beams are also explored. The effects produced on the droplet were studied pulse by pulse and depend on: droplet’s content, beam wavelength, power and focusing conditions, irradiation geometry and adhesion of the bead to the capillary on which it is suspended. The laser pulses energies were varied in four steps: 0.25mJ, 0.4mJ, 0.7mJ and 1mJ. The pulse full time width was 5ns and the typical focus diameter on the droplet was 90μm; the beam had a relatively low divergence around the focus point. The microdroplets and the modification/evolution of their shapes are visualised by recordings performed at 10kframes/second. Following a microdroplet interaction with the laser beam one may also produce at a controlled moment in time nanodroplets propagating at high (probably supersonic) speeds and microdroplets propagating at slower speeds. One may also produce pendant droplets of smaller dimensions than the initial one as well as micro/nano gas bubbles in the pendant droplet’s material/volume. In a second set of experiment was recorded at high speed the behaviour of the microdroplets of Rhodamine 6G in distilled water at resonant interaction with similar laser pulses, at the same power levels. The optical phenomena considering that the microdroplets contents are Newtonian liquids which dominate the beads behaviour at interaction with the laser beams, are discussed

In-beam fast-timing measurements in 103,105,107Cd

Fast-timing measurements were performed recently in the region of the medium-mass 103,105,107Cd isotopes, produced in fusion evaporation reactions. Emitted gamma-rays were detected by eight HPGe and five LaBr3:Ce detectors working in coincidence. Results on new and re-evaluated half-lives are discussed within a systematic of transition rates. The $7/2_1^+$ states in 103,105,107Cd are interpreted as arising from a single-particle excitation. The half-life analysis of the $11/2_1^-$ states in 103,105,107Cd shows no change in the single-particle transition strength as a function of the neutron number

Dilution in Laser Cladding with Ni-Based Powders

This study addresses to the laser cladding of nickel-based powders on stainless steel substrate. A TRUMPH pulsed laser and a coaxial cladding module are used to fabricate single tracks on AISI 304 substrate. The influence of the laser power on the geometric characteristics and microstructure of the cladded layer is investigated using optical and scanning electron microscopy and energy dispersive X-ray spectroscopy. Dilution is determined using the melt depth of the cladded tracks and validated using the local chemical microanalysis. The results showed that laser power have a major influence on the dilution and melted area of the laser cladded tracks

Influence of Titanium Additions on The Electrochemical Behaviour of NiCr/Ti Laser Cladded Coatings

In this research, the electrochemical evaluation of NiCr/Ti laser cladded coatings in simulated polymer electrolyte membrane fuel cells (PEMFCs) environment was investigated. The Laser Cladding technique was used to develop protective coatings on mild steel substrate using NiCr-based powders mixed with 12.5, 15, 17.5 and 20 wt.% Ti additions. The samples were tested at room temperature in Na2SO4 0.1M + 0.1 ppm F-. The potentiodynamic polarization curves are presented before and after the samples were subjected to accelerated stress tests, for 6 hours each, at +0.736 V (cathodic environment) and at -0.493 V (anodic environment). Afterwards, scanning electron microscopy (SEM) was used to investigate the effect of Ti addition in terms of morphology. Energy-dispersive X-ray spectroscopy (EDS) was performed for chemical evaluation of the surface after corrosion tests

Fast-timing measurements in 95,96Mo

Half-lives of the 19/2+ and 21/2+ states in 95Mo and of the 8+ and 10+ states in 96Mo were measured. Matrix elements for yrast transitions in 95Mo and 96Mo are discussed.Comment: Proceedings of XIX International School on Nuclear Physics, Neutron Physics and Applications, Varna, Bulgaria, 2011, 5 pages, 6 figure

A fluorescent Arg–Gly–Asp (RGD) peptide–naphthalenediimide (NDI) conjugate for imaging integrin <em>α_vβ₃in vitro</em>

We have developed a fluorescent peptide conjugate (TrpNDIRGDfK) based on the coupling of cyclo(RGDfK) to a new tryptophan-tagged amino acid naphthalenediimide (TrpNDI).</p

Identification of the crossing point at N=21 between normal and intruder configurations

The beta(-) decay of Mg-34 was used to study the Al-34 nucleus through. spectroscopy at the Isotope Separator On-Line facility of CERN. Previous studies identified two beta-decaying states in Al-34 having spin-parity assignments J(pi) = 4(-) dominated by the normal configuration pi(d(5/2))(-1)circle times nu(f(7/2)) and J(pi) = 1(+) by the intruder configuration pi(d(5/2))(-1) circle times nu(d(3/2))(-1) (f(7/2))(2). Their unknown ordering and relative energy have been the subject of debate for the placement of Al-34 inside or outside the N = 20 "island of inversion." We report here that the 1(+) intruder lies only 46.6 keV above the 4(-) ground state. In addition, a new half-life of T-1/2 = 44.9(4) ms, that is twice as long as the previously measured 20(10) ms, has been determined for Mg-34. Large-scale shell-model calculations with the recently developed SDPF-U-MIX interaction are compared with the new data and used to interpret the mechanisms at play at the very border of the N = 20 island of inversion.Peer reviewe

Decay studies of the long-lived states in Tl-186

Decay spectroscopy of the long-lived states in Tl-186 has been performed at the ISOLDE Decay Station at ISOLDE, CERN. The a decay from the low-spin (2(-)) state in Tl-186 was observed for the first time and a half-life of 3.4(-0.)(4)(+0.5) s was determined. Based on the alpha-decay energy, the relative positions of the long-lived states were fixed, with the (2(-)) state as the ground state, the 7((+)) state at 77(56) keV, and the 10((-)) state at 451(56) keV. The level scheme of the internal decay of the Tl-186(10((-))) state [T-1/2 = 3.40(9) s], which was known to decay solely through emission of 374-keV gamma-ray transition, was extended and a lower limit for the beta-decay branching b(beta) > 5.9(3)% was determined. The extracted retardation factors for the gamma decay of the 10((-) )state were compared to the available data in neighboring odd-odd thallium isotopes indicating the importance of the pi d(3/2) shell in the isomeric decay and significant structure differences between Tl-184 and Tl-186.Peer reviewe