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Our paper reports results of speciation analysis of arsenic(III) and (V) in the exchangeable fraction of the marine sediments from the Andaman Sea. The sediments were collected from the coastal zone at the coast of Thailand affected by the 2004 tsunami waves. The samples were extracted with phosphate buffer and then subjected to determination of inorganic species of arsenic by HPLC-HG-AAS. A correlation between the contents of arsenic and grain size of the sediments was found. Higher content of As(III) established in fine grain fraction of the sediment can suggest its deposition by tsunami. [ABSTRACT FROM AUTHOR]

Recent numerical simulation of tsunami propagation proposed a new hypothesis about the origin of the 1771 tsunami that devastated the southwest Ryukyu district of Japan; a slip of the East Ishigaki Fault, a 44 km-long fault lying 50km off the east coast of Ishigaki Island, might be the cause of the 1771 tsunami. The present study is to test this hypothesis through visual observation by means of the precise seafloor image collected by the Hyper-Dolphin remotely operated vehicle. The hypothesis may be proved if definite evidence of a slip along the whole fault is obtained. Investigating the fault was accomplished by a reconnaissance survey at three representing fault segments: southern, central and northern. The result of the survey at the southern segment shows that the main fault scarp is covered by many large boulders. On the escarpment, 6m sections with a gradient of almost 90 degrees were observed. The result of the survey at the central segment shows similar characteristics as that at the southern segment. The northern segment was characterized by wide exposure of limestone outcrop with many cracks and fissures on the outcrop which represents nascent faulting. These facts suggest the northward propagation of the faulting along the main scarp. The result demonstrates that the amount of displacement at the fault segments is not uniform. This does not support the assumption taken into the numerical simulation; thus, it is unlikely that the slip at the fault generated the 1771 tsunami, even though simultaneous rupture at multiple fault segments are taken into account. [ABSTRACT FROM AUTHOR]

On December 26th, 2004, a tsunami hit the Andaman Sea coast of Thailand, leaving bimodal tsunami deposits in the coastal zone. Granite boulders and sandy tsunami deposits were investigated near Thap Lamu Navy Base in Phang Nga Province, Thailand. Boulders (< 2.5m³) were mostly scattered close to a tidal inlet on a flat plain elevated 1-2m above the high tide water level, reaching up to 140m inland. Most boulders had oyster shell remnants over their surface, which suggests that they were dragged from the nearby shore. The tsunami also brought a sheet of medium to coarse grained sand, with thickness ranging from a few mm up to 37cm. The distribution of deposits was mainly controlled by the existing topography. Another group of granite boulders was found between 150 and 300m from the coastline, at elevations of 2m and more. Their size reached 5.5m³. This second group of boulders may have been transported by an ancient tsunami. [ABSTRACT FROM AUTHOR]

Three sandy beaches on Phuket and Kho Khao islands, Thailand, were monitored annually to study the short- and long-term impacts of the 2004 tsunami on their meiofauna assemblages and sediment characteristics. The sediment grain size compositions changed significantly within one year after the tsunami (improved sorting and less negatively skewed distributions), but meiofauna assemblages did not. The fast recolonization of the beaches after the tsunami confirmed that meiofauna is highly resilient to ecosystem disturbances. The tsunami was not observed to have a long-term impact on meiofaunal assemblages. [ABSTRACT FROM AUTHOR]

Our paper reports results of a study on the bioavailability of selected elements from sediments deposited by the tsunami event of 26 December 2004 in south Thailand. In January 2005, 15 samples of the sediments deposited by the tsunami were collected at four different localities. The reference sample was collected in an area not affected by the tsunami. In the acid leachable sediments fraction (the bioavailable fraction) the contents of 27 selected elements (Be, Ga, Bi, Rb, Cs, Sn, Mn, Re, Co, Rh, Ru, Mo, V, Nb, Ta, Zr, Sc, Th, Pt, La, Ce, Nd, Eu, Gd, Tb, Ho, Lu) were determined using ICP-MS. The measurements were repeated after one year to establish a potential effect of the rainy season on the content of these elements in this fraction. [ABSTRACT FROM AUTHOR]

Heavy mineral assemblages were studied in onshore sandy deposits from the 26 December 2004 tsunami on Kho Khao Island, southern Thailand. The most common minerals included tourmalines, zircon, muscovite, biotite, limonites and opaque minerals. An abundance of micas and depletion in tourmalines allowed us to distinguish the tsunami deposits from modern beach sediments and pre-tsunami soils. Major lateral and vertical changes in the studied profiles were related to an increase in flake-shaped micas upward in the tsunami sequence as well as landward. These variations, although documented for one grain size fraction, corresponded well with changes in the grain size distributions of the whole samples. The observed changes probably reflect wave hydrodynamics and a change in the sedimentation mode from bed-load deposition to settling of the suspended load. [ABSTRACT FROM AUTHOR]

There have been very few quantitative studies of the intertidal and shallow water biota of the Andaman Coast of Thailand and thus it was very difficult to provide precise estimates of the impact of the tsunami on coastal resources. Some quantitative data from Laem Son National Park existed, having been collected by the present authors, and these indicated that the most severe impacts were on the intertidal sand beach fauna, on rocky shore assemblages and on the seaward edge of mangrove forests. Inside the forests there was heavy deposition of coarse sediment on the forest floor and this led to changes in the species composition of the infauna. Most, but not all, sea grass beds escaped serious damage. By 2008 intertidal sediment assemblages contained a similar number of individuals to that recorded before the tsunami. Pre-tsunami data indicate that open coast, estuarine and seagrasses assemblages are naturally highly variable and thus were well adapted to recovering from the tsunami disturbance. Offshore sediments lack pre-tsunami information, but they too appear to be normal. Size frequency analysis of a population of the heart urchin Brissopsis luzonicus indicate that some individuals survived the tsunami but that there is heavy domination by the first post-tsunami cohort suggesting heavy colonization of disturbed seafloor. The trees in the seaward fringe of the most exposed mangrove forests still have to recover from tsunami damage, although the benthic fauna within the forest has returned. [ABSTRACT FROM AUTHOR]

Tsunami deposits are often characterized by specific diatom assemblages, which may indicate sediment provenance and help identify paleotsunami deposits. In the present study diatom assemblages were studied in tsunami deposits left by the 2004 tsunami in Thailand, as well as in beach sediments, inner shelf marine sediments and freshwater ponds and streams. The assemblages in tsunami deposits had chaotic structure and consisted of species found in all the studied habitats, suggesting erosion of terrestrial and marine sediments by tsunami. The diatom frustules in tsunami deposits were generally rare and often damaged due to excessive wave force. The most common identified species were Amphora turgida Gregory, Cocconeis scutellum Ehrenberg, Diplomenora cocconeiformis (Schmidt) Blazé, Eunotogramma marinum (W. Smith) Peragallo (typical for benthos of marine and brackish environments), and taxa common in freshwaters, including Cyclotella ocellata Pantocsek, Cocconeis placentula Ehrenberg and Encyonema silesiacum (Bleish) D.G. Mann. [ABSTRACT FROM AUTHOR]

Our study presents the results of determining labile aluminium form in samples from the 2004 tsunami-affected coastal zone of Thailand. The samples were collected from tsunami deposits, beach sediments, sediments underlying the tsunami deposits (pre 2004 tsunami soil), as well as from soils from areas, that were not flooded. The extraction of the labile form of aluminium was performed using 3 mol L-1 HCl in twelve grain size fractions. In the surface layer samples the highest concentrations were determined in the tsunami deposits in fractions <0.063 mm (5850 mg kg-1). The highest determined concentration in the whole set of investigated samples occurred in soil sample in fractions 0.09-0.125 mm (19770 mg kg-1). An increase in concentration of labile aluminium form, along with decreasing grain diameter, was observed in samples from all the studied settings. In general, concentrations were higher in soil samples not affected by the tsunami. This is probably due to steady weathering of minerals during soil forming processes and removal of sediment grain surface coatings potentially enriched in labile Al during high energy transport by tsunami. [ABSTRACT FROM AUTHOR]

The 2004 Indian Ocean tsunami transported large boulders shoreward at Pakarang Cape, Thailand. To elucidate boulder transport processes using their original locations, initial tsunami waveform, and coastal profiles, we conducted a cross-sectional calculation. Our results indicate that the tsunami (trough arrives first) might have displaced boulders and cast some on the tidal bench. However, if the wave crest arrives first, only some reef-edge boulders are displaced and emplaced on the tidal bench. More and larger boulders are displaced and deposited on the tidal bench when the reef slope is gentle, as at Pakarang Cape, than for a steep slope case. [ABSTRACT FROM AUTHOR]

The distribution of Ca, Mg, K, Na, Si, P, S, Al, V, Mn, Fe, Co, Cu, Ni, Zn, Sr, Mo, Cd, Sb, As, Bi, Pb, Tl, Th, U, Ti, Cr, Ba and REE (determined by ICP-MS, ICP-AES, XRF and AAS methods) in bottom sediments of the southern Baltic as well as the Vistula and Szczecin Lagoons were discussed. Based on enrichment factors (EFs) the accumulation of the chemical elements in surficial sediment with respect to their concentration in Earth's crust showed that Cd, Pb, Cu, Zn and Ag in coastal regions seem to be generally anthropogenic in origin. It is shown that the sediments of the Szczecin Lagoon are the most polluted by heavy metals, especially Cd, Zn and Pb, and that the degree of heavy-metal pollution decreases substantially on passing from the Szczecin Lagoon to the Pomeranian Bay and then on passing to the Bornholm Deep and Slupsk Furrow. Fluffy material from the Oder estuary appears to be the main source of heavy metals in the muddy sediments of the Bornholm Deep. The distribution of the rare earth elements (REE) in sediments of the Polish EEZ is more complex than previously thought and may be controlled by the input of Fe-organic colloids from rivers and the presence of detrital material in the sediments. The rare earth element (REE) patterns in sediments from the study region do not appear to have been greatly modified during transport from their source into the southern Baltic. In each of the study areas, there is a slight enrichment in the LREE relative to the HREE in the sediments compared to the NASC. The lack of significant anomalies for the redox-sensitive elements such as Ce and Eu implies that redox processes have marginal significance in modifying the distribution of the REE in the sediments studied. Chemometric techniques (FA, EMA) appeared to be useful for interpreting the spatial differences of chemical element concentrations in the study area. [ABSTRACT FROM AUTHOR]

This study documents seafloor morphology and sediments based on multibeam, side-scan sonar and boomer surveys, as well as sediment samples taken on the inner to mid shelf of the Andaman Sea after the 2004 Indian Ocean tsunami. Preservation of submarine relief in former underwater mining areas points to limited impact of the tsunami, while channel structures parallel to the observed tsunami backwash indicate a possible higher impact. Therefore, the tsunami impact seems to be focused on some areas. The impact was probably most effective during the backwash, when stiff mud deposits containing grass, wood fragments and shells were transported by high density backwash flows. Moreover, several boulders, which might have been deposited during the tsunami backwash flow, were found in the channels in front of Pakarang Cape. [ABSTRACT FROM AUTHOR]

The impacts of the 26th December 2004 Indian Ocean tsunami were examined on three separate coastal sectors in the west, north and east of Banda Aceh. The most vulnerable coasts are the soft coasts, such as mangroves, and the least vulnerable are the rocky headlands with the sandy coasts occupying a broad intermediate position. The extent of impact for each category of coasts appears to vary with the tsunami wave height and other characteristics. Coastal recovery was remarkably rapid, especially for sandy beaches. In some cases, foredunes returned to the coast. The impacts and recovery processes provide valuable lessons for coastal management, for example, in the replanting of mangroves and other coastal vegetation in the modified coastal environments and the questionable construction of seawalls on accreting coasts. In years to come, the tsunami impacts would disappear, except for modifications by human activities. [ABSTRACT FROM AUTHOR]

Abstract: We review, in a self-contained and pedagogical manner, recent developments and techniques for the evaluation of scattering amplitudes of planar SYM theory at both weak and strong coupling. Special emphasis is placed on the newly discovered connection between a special class of amplitudes and the expectation values of particular cusped light-like Wilson loops. [Copyright &y& Elsevier]

Copyright of Canadian Geotechnical Journal is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: The effect of an isolated submarine obstacle on the motion of fluid particles in a periodic external flow is studied within the framework of the barotropic, quasi-geostrophic approximation on -plane. The concept of background currents advanced by Kozlov [1995. Background currents in geophysical hydrodynamics. Izvestia, Atmos. Oceanic Phys. 31 (2), 245–250] is used to construct a dynamically consistent stream function satisfying the potential vorticity conservation law. It is shown that a system of two topographic vortices revolving about a rotation center can form in a circular external flow. Unsteady periodic perturbations, associated with either variations in the background current or deviations of the external flow from circulation, are analyzed. Unsteadiness in the external flow essentially complicates the pattern of the motion of fluid particles. Vortex-type quasi-periodic structures, identified with nonlinear resonances that form in Lagrangian equations of fluid particle advection, are examined. They either surround the stationary configuration by a vortex chain—a ringlet-like structure [], or they form a complex-structure multivortex domain. Asymptotic estimates and numerical modeling are used to study the distribution and widths of the nonlinear resonance domains that appear under unsteady perturbations of different types. The onset of chaotic regimes owing to the overlapping of nonlinear resonance domains is analyzed. Transport fluxes determined by chaotic advection and barriers for transport (KAM-tori) and the conditions of their existence are studied. The relation of the rotation frequency of fluid particles on their initial position (when the dependence is calculated in the undisturbed system) is shown to completely determine the main features of the pattern of Lagrangian trajectories and chaotization effects. Because of nonlinear effects, the domain involved in quasi-periodic and chaotic motions can be much larger than the domain occupied by steady topographic vortices. The results of study by Sokolovskiy et al. [1988. On the influence of an isolated submerged obstacle on a barotropic tidal flow. Geophys. Astrophys. Fluid Dyn. 88(1), 1–30] concerning the due regard on the irrotational background component as the necessary factor for the transportation of fluid particles from the vortex domain to infinity are confirmed. [Copyright &y& Elsevier]

Since the discovery of the Earth’s core a century ago, and the subsequent discovery of a solid inner core (postulated to have formed by the freezing of iron) seismologists have striven to understand this most remote part of the deep Earth. The most direct evidence for a solid inner core would be the observation of shear-mode body waves that traverse it, but these phases are extremely difficult to observe. Two reported observations in short-period data have proved controversial. Arguably more successful have been studies of longer-period data, but such averaging limits the usefulness of the observations to reported sightings. We present two observations of an inner-core shear-wave phase at higher frequencies in stacked data from the Japanese High-Sensitivity Array, Hi-Net. From an analysis of timing, amplitude and waveform of the ‘PKJKP’ phase we derive constraints on inner-core compressional-wave velocity and shear attenuation at about 0.3 Hz which differ from standard isotropic core models. We can explain waveform features and can partially reconcile the otherwise large differences between core wavespeed and attenuation models that our observations apparently suggest if we invoke shear-wave anisotropy in the inner core. A simple model of an inner core composed of hexagonal close-packed iron with its c axis aligned perpendicular to the rotation axis yields anisotropy that is compatible with both the shear-wave anisotropy that we observe and the well-established 3 per cent compressional-wave anisotropy. [ABSTRACT FROM AUTHOR]

We study the static shape of charged drops of a conducting fluid placed over a solid substrate, surrounded by a gas, and in absence of gravitational forces. The question can be formulated as a variational problem where a certain energy involving the areas of the solid-liquid interface and of the liquid-gas interface, as well as the electric capacity of the drop, has to be minimized. As a function of two parameters, Young's angle θY and the potential at the drop's surface V0, we find the axisymmetric minimizers of the energy and describe their shape. We also discuss the existence of symmetry-breaking bifurcations such that, for given values of θY and V0, configurations for which the axial symmetry is lost are energetically more favorable than axially symmetric configurations. We prove the existence of such bifurcations in the limits of very flat and almost spherical equilibrium shapes. All other cases are studied numerically with a boundary integral method. One conclusion of this study is that axisymmetric drops cannot spread indefinitely by introducing sufficient amount of electric charges, but can reach only a limiting (saturation) size, after which the axial symmetry would be lost and finger-like shapes energetically preferred. [ABSTRACT FROM AUTHOR]

The phenomenon of quantum superposition, which allows a physical system to exist in different states ‘simultaneously’, is one of the most bizarre notions in physics. Here we illustrate an even more bizarre example of it: a superposed state of a physical system consisting of both an ‘older’ version and a ‘younger’ version of that system. This can be accomplished by exploiting the special relativistic effect of time dilation featuring in Einstein’s famous twin paradox. [ABSTRACT FROM AUTHOR]

We determined some basic properties of stars that produce spectacular gamma-ray bursts at the end of their lives. We assumed that accretion of the outer portion of the stellar core by a central black hole fuels the prompt emission and that fall-back and accretion of the stellar envelope later produce the plateau in the x-ray light curve seen in some bursts. Using x-ray data for three bursts, we estimated the radius of the stellar core to be ~(1 - 3) × 1010 cm and that of the stellar envelope to be ~(1 - 2) × 1011 cm. The density profile in the envelope is fairly shallow, with ρ - r-2 (where ρ is density and r is distance from the center of the explosion). The rotation speeds of the core and envelope are ~0.05 and ~0.2 of the local Keplerian speed, respectively. [ABSTRACT FROM AUTHOR]

The scaling requirements of conventional DRAMs lead to the recent developments of capacitorless single-transistor (iT) DRAM in SOT technology. We propose a new concept of iT-DRAM (named MSDRAM), which is simple to fabricate, program, and read. Its basic mechanism is the metastable dip hysteresis effect, which takes advantage of the dynamic coupling between front and back interfaces in SO! transistors. Systematic measurements and simulations show that MSDRAMs are suitable for low-power applications, as they exhibit negligible OFF-state current and long retention time even for 50-nm devices. [ABSTRACT FROM AUTHOR]

In this letter, the capacitance characteristics of RF LDMOS transistors with different temperatures and layout struc- tures were studied. In a conventional fishbone structure, the peaks in capacitances decrease with increasing temperature. For the ring structure, two peaks in a capacitance-voltage curve have been observed at high drain voltages due to the additional corner effect. In addition, peaks in gate-to-source/body capacitance decrease and peaks in gate-to-drain capacitance increase with increasing temperature at high drain voltages. By analyzing the effects of temperature on threshold voltage, quasi-saturation current, and drift depletion capacitance, the variations of capacitances with temperature were investigated. [ABSTRACT FROM AUTHOR]

In this letter, hot-carrier-induced on-resistance (Ron) degradation in lateral DMOS transistors with different n-type drift-drain (NDD) region concentration is investigated. Increasing NDD concentration results in greater bulk (Ib) and gate currents (Ig), but Ron degradation is improved. Technology computer-aided design simulations reveal that high NDD concen- tration increases impact-ionization rate in accumulation (related to Ib increase) and channel regions (related to Ig increase) but reduces impact-ionization rate in spacer region. Charge-pumping data confirm that hot-carrier-induced interface state created in the spacer region is reduced, leading to improved Ron degradation in high-NDD-concentration device. [ABSTRACT FROM AUTHOR]

The article reports on New York city's vulnerability to coastal flooding. It is said that New York City and the adjacent region of northern New Jersey and Long Island, New York are built around a complex of narrow rivers, estuaries, islands, and waterways that are strongly influenced by tides and weather. It is also said that much of the Metropolitan region is less than five meters above mean sea level. Out of this, about 260 km2 is said to be at risk from storm surge flooding by a 100-yr flood event for both tropical systems and nor'easter cyclones.

Single crystals of MoSxSe2-x (x=0, 1, 2) have been grown by direct vapour transport method. Pressure-dependent d.c. electrical resistivity measurements have been carried out on the grown crystals to check the possibility of phase transition up to 8 GPa. However, no such transition is observed in the present case but a decrease in resistivity is found with increase in pressure. The observed results have been analysed and discussed on the basis of band structure. [ABSTRACT FROM AUTHOR]

Abstract: Neither a higher hardness nor higher mechanical properties (yield strength, ultimate tensile strength, impact energy, and %elongation) appear to be exclusive or even reliable criteria for predicting the ballistic performance of martensitic armour steels, as shown in our previous work [K. Maweja, W.E. Stumpf, Mater. Sci. Eng. A (February), submitted for publication]. An alternative design methodology for tempered martensitic armour steels is, therefore, proposed which is based on the effect of retained austenite on the ratio of the yield to ultimate tensile strength (YS/UTS), the microstructure of the tempered martensite and its martensite start temperature M s. This approach was developed using 6mm thick armour plates and later was successfully applied to the design of eight experimental armour steels with plate thicknesses ranging from 4.7 to 5.2mm and tested by the standard R4 (5.56mm rounds) ballistic test. [Copyright &y& Elsevier]

Abstract: This paper reports the results of an investigation of plates produced by the advanced thermomechanical processing (TMP) schedules, which were designed using the results of a laboratory study. There were two steel compositions that corresponded to X-80 with carbon contents 0.04 and 0.07wt.%, respectively. The variation in microstructure, hardness, tensile properties and Charpy impact properties with TMP schedule were determined, and compared with the expected requirements for X-100 linepipe steel. The relationships between microstructure and mechanical properties were experimentally obtained and discussed. [Copyright &y& Elsevier]

Abstract: Bi2O3·B2O3 glasses doped with rare-earth oxides (RE2O3) (RE3+ =La3+, Pr3+, Sm3+, Gd3+, Er3+ and Yb3+) were prepared by the melting–quenching method. The relationships between composition and properties were demonstrated by IR, DSC, XRD and SEM analysis. The results show that the network structure resembles that of undoped Bi2O3·B2O3 glass, composing of [BO3], [BO4] and [BiO6] units. RE2O3 stabilizes the glass structure as a modifier. Transition temperature (T g) increases linearly with cationic field strength (CFS) of RE3+. La2O3, Pr2O3, Sm2O3 and Gd2O3 are benefit to promote the formation of BiBO3 crystal. When Er2O3 and Yb2O3 are introduced, respectively, the main crystal phase changes to Bi6B10O24. Transparent surface crystallized samples are obtained by reheating at 460–540°C for 5h. In this case, needle like BiBO3 crystal or rare-earth-doped BiBO3 crystal (Pr x Bi1−x BO3 and Gd x Bi1−x BO3) are observed, which is promising for non-linear optical application. [Copyright &y& Elsevier]

Abstract: In this work, numerical simulations for predicting uni- and multi-axial ratchetting behaviors are carried out, using a polycrystal plasticity model. In this multi-scale modeling, the single crystal behavior is based on crystallographic slip (intragranular scale), whereas the polycrystal behavior is obtained from an explicit transition rule to calculate the local stresses and strains (intergranular scale). A systematic study is performed to show the effect of intergranular and intragranular hardening on the ratchetting behavior. For illustrative purposes, two examples are presented: the model is applied to simulate the experimental results from the literature for a 316 austenitic stainless steel and for a 1026 carbon steel. It was demonstrated that the polycrystalline model was successful in describing the inelastic behavior of the two considered materials adequately. [Copyright &y& Elsevier]

Abstract: A crystal plasticity finite element (CPFE) method was applied to evaluate cross-grain deformation heterogeneity and its implication on texture evolution during equal channel angular extrusion (ECAE) of pure copper. The simulations were conducted for one to four passes of ECAE via route C, assuming simple shear in each pass at the macroscopic level. Analyses of the stress and strain distributions reveal considerable deformation heterogeneities across individual grains in the polycrystal. The grain interactions are found to be remarkable after even-numbered passes and they partly contribute to the retained shear textures. The CPFE model captures very well the experimental textures after odd-numbered passes; however, it is not able to model the measured textures subsequent to even-numbered passes, and the results are only slightly improved as compared to a visco-plasticity self-consistent polycrystal model. These results suggest that dedicated considerations of deformation heterogeneities at both the macro- and meso-levels are necessary in modeling texture evolution during severe plastic deformation. [Copyright &y& Elsevier]

A common problem in high capacity trays is the difficulty of establishing a liquid seal of hanging or truncated downcomers since the hanging or truncated downcomers came out. When the downcomer seal is lost, the vapor rises up through the downcomer, which may cause tray instability and poor separation. For the downcomer unseal or vapor-rise-up, it was found that there exist two regimes of free vapor-rise-up regime and dynamic vapor-rise-up regime. The mechanism of free vapor-rise-up is lower liquid height than the tray pressure drop, whereas the mechanism of dynamic vapor-rise-up is the driving force of the tray pressure drop. Using the hydraulic model of dualflow tray, the vapor-rise-up model in dynamic regime was developed. The experiments were carried out in a 500 mm-diameter transparent plexiglass column with air-water system. From the experimental data, the vapor-rise-up correlation was obtained. The free vapor-rise-up regime converts into dynamic regime with the increase of the vapor rate, and the transition point is a certain real velocity of rise-up vapor. For preventing the vapor-rise-up, a seal line is required. With the definition of the rise-up vapor being limited to a certain ratio of rise-up vapor rate to liquid rate, the seal line is qualitatively obtained from the vapor-rise-up model. The seal line has the minimum liquid rate, which is in accord with the seal line by Li et al. (Li, Y.M., Yu, X.M. and Yao, K.J., 2004, Dynamic seals on hanging downcomers. Chem Eng Res Des, 82: 1]. [ABSTRACT FROM AUTHOR]

The paper deals with the tray-to-tray method for determining the required number of trays in gas-liquid columns in case of intensive entrainment. The equations for estimation of the tray efficiency are derived for top, bottom and intermediate trays, and they incorporate the number of gas and liquid phases transfer units, stripping factor, Peclet number of mixing and fractional entrainment. These equations can be simplified to the well-known one-parametric diffusion model explained in Bubble Tray Design Manual (1958) [Bubble Tray Design Manual, 1958, AIChE, New York] for case of negligible entrainment. The algorithm of tray-to-tray method is based on tray efficiency calculated for each tray separately and it enables the calculation of the number of required trays, starting from the bottom tray. Given example shows how the excessive entrainment decreases of the driving force of the process. [ABSTRACT FROM AUTHOR]

Abstract: The aza-Michael addition of weakly nucleophilic amines with α, β-unsaturated compounds like esters, nitriles and amides has been carried out efficiently using Y(NO3)3 ·6H2O as a novel catalyst under solvent-free conditions. The catalyst exhibited remarkable activity and the methodology was applicable to a wide variety of aryl/hetero-aryl amines having different steric and electronic properties giving high yields of desired adducts at ambient conditions. [Copyright &y& Elsevier]

Abstract: Montmorillonite K-10 is an efficient, cost-effective and recyclable catalyst for a one-pot synthesis of quinoxaline derivatives in water at ambient temperature. This procedure presented is operationally simple, practical and green. [Copyright &y& Elsevier]

Abstract: A convenient and green method for the synthesis of aromatic 2-oxazolines, 2-imidazolines and 2-thiazolines using tungstophosphoric acid (TPA), a commercially available, stable and reusable catalyst, from the reaction of aromatic nitriles and 2-aminoalcohols, ethylenediamine or 2-aminoethanethiol under solvent-free conditions is reported. It is noteworthy that this procedure could be used for selective synthesis of mono- and bis-oxazolines and imidazolines from dicyanobenzene. In three cases the catalyst could be reused several times without significant loss of its catalytic activity. [Copyright &y& Elsevier]

Abstract: An efficient synthesis of benzoin methyl ether with benzaldehyde and methanol in the presence of MgCoAl–hydrotalcite catalyst has been developed. By this new method, not only the cyanide poisoning is avoided, but also the synthesis of benzoin methyl ether can be completed in one step instead of the traditional two steps with both condensation and etherification. A new way for major industrial processes to synthesize clean benzoin methyl ether was explored. [Copyright &y& Elsevier]

Abstract: A pyridine catalyzed reaction between tetracyanoethylene and various activated CH-acid compounds to afford the corresponding pyran annulated heterocyclic ring systems in high yield at room temperature within a few minutes, is described. The work-up procedure is very simple and the products do not require further purification. [Copyright &y& Elsevier]

Abstract: The catalytic production of lactic acid from biomass derivatives over solid base catalysts was studied for future sustainable societies. The activated hydrotalcites catalyzed the lactic acid production from d-glucose in flow reactors at 323K under water media. The number of accessible Brønsted-base sites of hydrotalcite (Mg/Al=2) activated at 723K as determined by the ion-exchange method with sodium salts, based on the OH/Al ratio, was about 39% which was much higher than that of the hydrotalcite activated at 573K. The catalytic activity for the lactic acid production showed a linear increase with the number of the Brønsted-base sites. [Copyright &y& Elsevier]

Abstract: was employed as a catalyst for the conversion of alcohols into the corresponding iodides using NaI in CH3CN at room temperature. Present procedure is found to be selective for the conversion of benzylic alcohols in the presence of saturated alcohols into benzylic iodides. The catalyst was characterized by XRD, FTIR, elemental analysis, BET surface area and TG–DTA techniques. This protocol provides a mild and efficient way for the one pot conversion of structurally diverse alcohols to their corresponding alkyl iodides with high selectivity. Display Omitted [Copyright &y& Elsevier]

Abstract: A convenient and efficient method for synthesis of substituted 2-amino-2-chromenes by the reaction of arylidenemalononitriles and 1-naphthol or via one-pot three-component condensation of aromatic aldehydes with malononitrile and 1-naphthol has been developed by using the inexpensive and environmentally friendly reagent I2/K2CO3 in aqueous medium. The method is simple and eco-friendly with good to high product yields in a short time. [Copyright &y& Elsevier]

Abstract: The mirror system of the HERA-B ring imaging Cherenkov (RICH) counter consists of two spherical and two planar mirrors, composed of altogether 116 mirror segments. Analysis of displacements of the Cherenkov ring center relative to the charged particle track, for given spherical–planar segment pairs, leads to accurate information regarding the orientation of individual mirror segments. The method for mirror calibration is described and the effect of applying the required corrections on the Cherenkov angle resolution of the HERA-B RICH is discussed. [Copyright &y& Elsevier]

Abstract: The relative energy stability of Van de Graaff type ion accelerators is typically limited to some . An inexpensive possibility to improve this situation was developed at the Forschungszentrum Dresden-Rossendorf. The method refers to the relatively stable periodic pattern of the acceleration voltage fluctuation in such accelerators. Future values of that fluctuation can be predicted with a high degree of certainty and can taken into account in the belt generator control in spite of the belt convolution caused fundamental reaction delay. The microcontroller based implementation of a “predictive fluctuation compensation” improves the relative acceleration voltage short time stability by a factor of 3–6 to well below . [Copyright &y& Elsevier]

Abstract: For DEcay SPECtroscopy (DESPEC) experiments with implanted radioactive beams a high resolution gamma tracking array is being designed at GSI. Exploiting the imaging capability of the array, a background suppression method is developed based on a separation of events originating from the target and from localized background sources. Monte-Carlo simulations show that the suppression of the background by a factor from 10 up to 100 or even more can be achieved. The Peak/Total ratio can be as well significantly increased. The dependence of the suppression efficiency on the detector properties is discussed. [Copyright &y& Elsevier]

Abstract: This article describes the technical implementation and the performance of the z-vertex trigger (CIP2k), which is part of the H1-experiment at HERA. The HERA storage ring and collider was designed to investigate electron (and positron) proton scattering at a center-of-mass energy of 320GeV. To improve the sensitivity for detecting non-standard model physics and other high momentum transfer phenomena, the HERA ring has been ungraded between 2000 and 2003 to increase the specific luminosity for the experiments. In order to cope with the increased event and background rate the experiments were upgraded, too. The CIP2k trigger system is based on a set of five cylindrical multiwire proportional chambers with cathode pad readout, and allows to distinguish between events induced by beam background and ep-interactions at the first trigger stage. The trigger decision is calculated dead-time free with a latency of in parallel to the beam clock at 10.4MHz. The trigger-logic is realized in large field programmable gate arrays (FPGA) using the hardware description language Verilog. The system is operational since October 2003. It suppresses background events with high efficiency and provides event timing information, as designed. [Copyright &y& Elsevier]

Abstract: Full three-dimensional (3D) simulations have been carried out on the BNL one-sided single-type column and dual-type column 3D Si detectors (p-type substrate). Due to the facts that columns are not etched all the way through, all electrodes are on the front side, and the backside is neither supported nor processed at all, the BNL one-sided 3D detectors are true one-sided detectors. Simulations show that the volume under the columns, where it is supposed to be dead space (about 10%), can be depleted at high biases with some modest electric field, leading to the possibility of recovering some sensitivity from this region. This region can also provide some sensitivity to particle tracks directly through the columns. The dual-type column detectors are the best in radiation hardness due to their low depletion voltages and short drift distances. Single-type column detectors are more radiation hard than the planar detectors due to their lower depletion voltages. Single-type column detectors are easier to process than dual-type column detectors, but have a more complicated, non-uniform electric field profile. The BNL one-sided 3D detectors were compared to various 3D detector structures developed by other institutes. The field profiles for all types of dual-type column 3D detectors are similar with just some minor differences on both surfaces (front and back). The BNL single-type column one-sided 3D detectors have some major differences from the Trento ones: (1) the high electric field is on the sensing electrode side (pixel or strip); and (2) it can develop some high electric field along the junction column as the bias voltage increases. [Copyright &y& Elsevier]

Abstract: In this work, a theoretical and computational study on the space charge dominated beams, extracted from a plasma ion source through a spherical and planer electrode is simulated and optimized. The influence of some electrode parameters—axial position, electrode diameter, material and shape—on ion current extracted from a plasma source were investigated and compared. The optimum values and conditions of the curvature of the plasma boundary, angular divergence, perveance, and the extraction gap were optimized to extract high quality beams. It has been shown that for a planar electrode system there is usually a minimum for optimum perveance versus angular divergence at about ≈0.6 for corresponding aspect ratios. This was assured by experimental data. The appropriate spherical electrode system focus the beam to a minimum value located at a distance equal to the focal length of the spherical extraction electrode. [Copyright &y& Elsevier]

Abstract: In radiation oncology applications, the need for higher-quality images has been driven by recent advances in radiation delivery systems that require online imaging. The existing electronic imaging devices commonly used to acquire portal images implement amorphous silicon (a-Si) detector, which exhibits poor image quality. Efforts for improvement have mostly been in the areas of noise and scatter reduction through software. This has not been successful due to inherent shortcomings of a-Si material. Cadmium telluride (CdTe) semiconductor has long been recognized as highly suitable for use in X-ray detectors in both spectroscopic and imaging applications. Development of such systems has mostly concentrated on single crystal CdTe. Recent advances in thin-film deposition technology suggest replacement of crystalline material with its polycrystalline counterpart, offering ease of large-area device fabrication and achievement of higher resolution as well as a favorable cost difference. While bulk CdTe material was found to have superior radiation hardness, thin films have not been evaluated from that prospective, in particular under high-energy photon beam typical of radiation treatment applications. We assess the performance of thin-film CdTe devices utilizing 6MeV photon beam and find no consistent trend for material degradation under doses far exceeding the typical radiation therapy detector lifetime dose. [Copyright &y& Elsevier]

Abstract: In order to produce a high brightness electron beam for the Frascati Linac coherent light source (SPARC) the use of an accelerating section with frequency equal to the fourth harmonic of the main S-Band Linac frequency is needed. This paper discusses the design and the realization of a compact X-Band linear accelerating section for obtaining 5MV average accelerating gradient, working at a frequency of 11.424GHz and operating on the standing wave mode. Numerical predictions compared with measurements made on a copper prototype at room temperature are reported. [Copyright &y& Elsevier]

Genetic diversity among 70 maintainers and two pollinators of sub-Saharan and Indian origin was studied for simple sequence repeat (SSR) loci using 34 primer pairs. A total of 213 alleles were detected with an average of 6.26 alleles per locus. Polymorphic information content (PIC) ranged from 0.05 to 0.96 with a mean of 0.58 for the SSR loci. Mean PIC across the linkage groups and number of alleles in dinucleotide motifs varied significantly. The lowest PIC (0.239) for linkage group 6 indicated comparatively conserved nature of this linkage group. Genetic similarity estimates ranged from 0.05 to 0.73 with an average value of 0.29. This indicated sufficient diversity among the maintainer and pollinator lines. The 72 lines fell in five clusters, and the clustering pattern corroborated with their pedigree and characteristic traits. Pollinator ICMR 356 was more diverse from the maintainer lines analysed, and can be a potential parent for pearl millet hybrid development. [ABSTRACT FROM AUTHOR]

Presence of substantial heterosis and economic hybrid seed production are two most desirable components for success of any commercial hybrid breeding programme. Thermosensitive genic male sterile (TGMS) lines of rice, in this regard, have tremendous potential in realizing further quantum jump in yield and economical hybrid seed cost. Analyses for combining ability and heterosis over optimum (120N : 60P2O5 : 40K2O kg/ha) and high (200N : 90P2O5 : 60K2O kg/ha) fertility environments for six traits were made in 2 years (2001 and 2002) using 120 hybrids of inter- and intra-subspecific nature derived from hybridization of 30 elite indica TGMS lines and four cultivars, viz., ‘Pant Dhan 4’ and ‘Ajaya’ (I = indica), ‘Taichung 65’ (J = japonica) and ‘IR 65598-112-2’ (TJ = tropical japonica) in line × tester mating design. Predominance of non-additive genetic variance suggested good prospects of hybrid breeding. Pooled analysis revealed highly significant variances for lines, general combining ability (GCA), specific combining ability (SCA) and line x tester. TGMS line 365-8S was the best general combiner for all the six traits including grain yield. Trend of relative mid-parent heterosis for grain yield, panicle length, grain number per panicle and earliness in flowering was I/TJ > I/J > I/I. For panicle number per plant and 1000-grain weight, trends were I/TJ > I/I > I/J and I/I > I/TJ > I/J, respectively. Grain yield recorded heterosis of 49.3%, 71.9% and 92.7% for I/I, I/J and I/TJ hybrid groups respectively. Effect of environments on the hybrid performance indicated better response of hybrids at high fertilizer dose. Study suggests greater prospects of combining improved japonica and tropical japonica germplasms having wide compatible gene with indica TGMS lines for exploitation of intersubspecific heterosis. [ABSTRACT FROM AUTHOR]