The late-time development of the Richtmyer–Meshkov instability

Measurements have been made of the growth by the Richtmyer–Meshkov instability of nominally single-scale perturbations on an air/sulfur hexafluoride (SF6) interface in a large shock tube. An approximately sinusoidal shape is given to the interface by a wire mesh which supports a polymeric membrane separating the air from the SF6. A single shock wave incident on the interface induces motion by the baroclinic mechanism of vorticity generation. The visual thickness delta of the interface is measured from schlieren photographs obtained singly in each run and in high-speed motion pictures. Data are presented for delta at times considerably larger than previously reported, and they are tested for self-similarity including independence of initial conditions. Four different initial amplitude/wavelength combinations at one incident shock strength are used to determine the scaling of the data. It is found that the growth rate decreases rapidly with time, ddelta/dt[proportional]t–p (i.e., delta[proportional]t1–p), where 0.67<~p<~0.74 and that a small dependence on the initial wavelength lambda0 persists to large time. The larger value of the power law exponent agrees with the result of the late-time-decay similarity law of Huang and Leonard [Phys. Fluids 6, 3765–3775 (1994)]. The influence of the wire mesh and membrane on the mixing process is assessed

Weakly commensurable arithmetic groups, lengths of closed geodesics and isospectral locally symmetric spaces

We introduce the notion of weak commensurabilty of arithmetic subgroups and relate it to the length equivalence and isospectrality of locally symmetric spaces. We prove many strong consequences of weak commensurabilty and derive from these many interesting results about isolength and isospectral locally symmetric spaces.Comment: 62 page

Instability of Rotationally Tuned Dipolar Bose-Einstein Condensates

The possibility of effectively inverting the sign of the dipole-dipole interaction, by fast rotation of the dipole polarization, is examined within a harmonically trapped dipolar Bose-Einstein condensate. Our analysis is based on the stationary states in the Thomas-Fermi limit, in the corotating frame, as well as direct numerical simulations in the Thomas-Fermi regime, explicitly accounting for the rotating polarization. The condensate is found to be inherently unstable due to the dynamical instability of collective modes. This ultimately prevents the realization of robust and long-lived rotationally tuned states. Our findings have major implications for experimentally accessing this regime.Comment: 9 pages with 5 figure

Systemic Therapy in Endometrial Cancer: Recent Advances.

Endometrial cancer is a chemosensitive disease. Studies have established a clear benefit of chemotherapy in advanced stages and trials are ongoing to define its role in early stages as well. As more molecular pathways are being elucidated there is increasing role for targeted agents and future looks quite promising. We did an extensive search both online and offline for all the relevant articles including chemotherapy and targeted therapy for endometrial cancer

Beneficiation of Bauxite

A primary objective of the beneficiation process is to reduce the silica content in the ore, as the latter reacts with caustic soda during the digestion step to precipitate out as insoluble sodium aluminium silicates, e.g. 2Na20.2 Al2O3.3 SiO2.2 H2O. This salt is eliminated from the process along with the insoluble iron and titanium oxides in red mud, consequently entailing the loss of valuable alumina and caustic soda from the process

MHD free convection-radiation interaction in a porous medium - part I : numerical investigation

A numerical investigation of two dimensional steady magnetohydrodynamics heat and mass transfer by laminar free convection from a radiative horizontal circular cylinder in a non-Darcy porous medium is presented by taking into account the Soret/Dufour effects. The boundary layer conservation equations, which are parabolic in nature, are normalized into non-similar form and then solved numerically with the well-tested, efficient, implicit, stable Keller–Box finite-difference scheme. We use simple central difference derivatives and averages at the mid points of net rectangles to get finite difference equations with a second order truncation error. We have conducted a grid sensitivity and time calculation of the solution execution. Numerical results are obtained for the velocity, temperature and concentration distributions, as well as the local skin friction, Nusselt number and Sherwood number for several values of the parameters. The dependency of the thermophysical properties has been discussed on the parameters and shown graphically. The Darcy number accelerates the flow due to a corresponding rise in permeability of the regime and concomitant decrease in Darcian impedance. A comparative study between the previously published and present results in a limiting sense is found in an excellent agreement

Beneficiation of Bauxite

BAUXITE deposits generally occur at or near the surface and are usually covered with shallow layer of overburden. The ore is almost invariably mined by open pit methods. The usual practice is to thoroughly strip and clear the overburden, after which the ore body is blasted to permit excavation by mechanical shovels. Some deposits contain highly siliceous clays and ferruginous materials distri-buted intimately throughout the ore, and it is often necessary to beneficiate the bauxite to provide a desired quality of product. A primary objective of the beneficiation process is to reduce the silica content in the ore, as the latter reacts with caustic soda during the digestion step to precipitate out as insoluble sodium aluminium silicates, e.g. 2Na2O.2Al203.3Si02.2 H20. This salt is eliminated from the process along with the insoluble iron & titanium oxides in red mud, consequently entailing the loss of valuable alumina and caustic soda from the process

QUANTIFICATION OF ANTICOAGULANTS DABIGATRAN, RIVAROXABAN, AND PRASUGREL BY CHROMATOGRAPHIC AND SPECTROMETRIC TECHNIQUES – REVIEW

A review is presented on different analytical techniques used for quantitative analysis of selected anticoagulants dabigatran, rivaroxaban, and prasugrel. Efforts have been made to collate all the relevant references to the extent possible. The review discusses the advantages and disadvantages of the cited analytical techniques, which will help to give insights into the methods used for estimation of selected anticoagulants such as dabigatran, rivaroxaban, and prasugrel, from clinical isolates, and its dosage forms. The review highlights the basic as well as advanced techniques performed for estimating dabigatran, rivaroxaban, and prasugrel. The techniques illustrated here have been demonstrated to be useful for quantitative determination of selected anticoagulants and may find application in analyzing other related properties