Hydrochemistry and Groundwater Quality Assessment of Dantewada District, Chhattisgarh, India

Hydrogeological investigation have been carried out in Dantewada district. Groundwater samples were collected from selected locations in month of September 2013 and analyzed for major and minor cations & anions. Piper Diagram identified Ca-Mg-HCO3 dominantin water in most of the samples. The dominance of anions and cations were of the order of HCO3-> SO42->Cl-> NO3-> PO42- and Mg2+>Ca2+> Na+> K+.Ionic plots indicating the predominance of alkaline earth over alkali and bicarbonate is due to the reaction of the feldspar minerals with carbonic acid in the presence of water. Water chemistry is guided by complex weathering process, ion exchange along with influence of geochemical condition. Keywords: hydrochemistry, weathering, ion-exchange, water-quality

Yieldlike Constitutive Transition in Shear Flow of Entangled Polymeric Fluids

We describe an unexpected constitutive transition in entangled polymer solutions. At and beyond a critical stress, the initial spatially homogeneous and well-entangled sample transforms from its entangled (coiled) state into a fully disentangled (stretched) state over a period during which the resulting shear rate increases in a spatially inhomogeneous fashion. In the mode of controlled shear rate, the sample exhibits a stress plateau over three decades. Flow birefringence and normal stress observations unravel additional features of these flow phenomena

Interfacial Stick-Slip Transition in Simple Shear of Entangled Melts

This article describes a systematic investigation of a discontinuous interfacial stick-slip transition (SST) in simple shear of monodisperse entangled 1,4-polybutadiene (PBD) and polyisoprene (PIP) melts with different molecular weights and architecture, using a specially designed controlled-force shear rheometer. The magnitude of the transition is found to be determined by the level of chain entanglement. Specifically, the dependence of extrapolation length b on molecular weight as b similar to M-w(3.4) and of the melt viscosity as b similar to eta is consistent with the observations based on capillary rheometric studies [X. Yang et al., Rheol. Acta 37, 415-423 (1998)]. The interfacial nature of the flow behavior is explicitly demonstrated by a surface treatment of the shearing plates and dependence of the abrupt increase of the apparent shear rate on the gap distance as well as by particle tracking velocimetry. The critical stress for different molecular weights of PBD and PIP is about 0.2 and 0.1 MPa, respectively, independent of molecular weight and architecture. These results are consistent with the previous conclusion of an interfacial SST as the origin of the discontinuous spurt flow behavior observed with pressure-driven capillary rheometry. The critical stress for the SST is found to be lower in simple shear flow. Finally, chain architecture is observed to also influence the magnitude of the SST apart from the level of chain entanglement. (c) 2006 The Society of Rheology

Decompositions of nn-Cube into 2mn2^mn-Cycles

It is known that the $n$-dimensional hypercube $Q_n,$ for $n$ even, has a decomposition into $k$-cycles for $k=n, 2n,$ $2^l$ with $2 \leq l \leq n.$ In this paper, we prove that $Q_n$ has a decomposition into $2^mn$-cycles for $n \geq 2^m.$ As an immediate consequence of this result, we get path decompositions of $Q_n$ as well. This gives a partial solution to a conjecture posed by Ramras and also, it solves some special cases of a conjecture due to Erde

Performance Testing and Analysis of Synchronous Reluctance Motor Utilizing Dual-phase Magnetic Material

While interior permanent magnet (1PM) machines have been considered the state-of-the art for traction motors, synchronous reluctance (SynRel) motors with advanced materials can provide a competitive alternative. 1PM machines typically utilize Neodymium 1ron Boron (NdFeB) permanent magnets, which pose an issue in terms of price, sustainability, demagnetization at higher operating temperatures, and uncontrolled generation. On the other hand, SynRel machines do not contain any magnets and are free from these issues. However, the absence of magnets as well the presence of bridges and centerposts limit the flux-weakening capability of a SynRel machine and limit the achievable constant power speed ratio (CPSR) without having to significantly oversize the machine and/or the power converter. 1n this paper, a new material referred to as the dual-phase magnetic material where nonmagnetic regions can be selectively introduced within each lamination will be evaluated for SynRel designs. The dual-phase feature of this material enables non-magnetic bridges and posts, eliminating one of the key limitations of the SynRel designs in terms of torque density and flux-weakening. This paper will present, the design, analysis and test results of an advanced proof-of-concept SynRel design utilizing dual-phase material with traction applications as the ultimate target application

Probing shear-banding transitions of the VCM model for entangled wormlike micellar solutions using large amplitude oscillatory shear (LAOS) deformations

We explore the use of large amplitude oscillatory shear (LAOS) deformation to probe the dynamics of shear-banding in soft entangled materials, primarily wormlike micellar solutions which are prone to breakage and disentanglement under strong deformations. The state of stress in these complex fluids is described by a class of viscoelastic constitutive models which capture the key linear and nonlinear rheological features of wormlike micellar solutions, including the breakage and reforming of an entangled network. At a frequency-dependent critical strain, the imposed deformation field localizes to form a shear band, with a phase response that depends on the frequency and amplitude of the forcing. The different material responses are compactly represented in the form of Lissajous (phase plane) orbits and a corresponding strain-rate and frequency-dependent Pipkin diagram. Comparisons between the full network model predictions and those of a simpler, limiting case are presented.National Science Foundation (U.S.) (NSF DMS-0807395)National Science Foundation (U.S.) (NSF DMS-0807330

Stress overshoot in a simple yield stress fluid: an extensive study combining rheology and velocimetry

We report a large amount of experimental data on the stress overshoot phenomenon which takes place during start-up shear flows in a simple yield stress fluid, namely a carbopol microgel. A combination of classical rheological measurements and ultrasonic velocimetry makes it possible to get physical insights on the transient dynamics of both the stress $\sigma(t)$ and the velocity field across the gap of a rough cylindrical Couette cell during the start-up of shear under an applied shear rate $\dot\gamma$. (i) At small strains ($\gamma <1$), $\sigma(t)$ increases linearly and the microgel undergoes homogeneous deformation. (ii) At a time $t_m$, the stress reaches a maximum value $\sigma_m$ which corresponds to the failure of the microgel and to the nucleation of a thin lubrication layer at the moving wall. (iii) The microgel then experiences a strong elastic recoil and enters a regime of total wall slip while the stress slowly decreases. (iv) Total wall slip gives way to a transient shear-banding phenomenon, which occurs on timescales much longer than that of the stress overshoot and has been described elsewhere [Divoux \textit{et al., Phys. Rev. Lett.}, 2010, \textbf{104}, 208301]. This whole sequence is very robust to concentration changes in the explored range ($0.5 \le C \le 3$ w/w). We further demonstrate that the maximum stress $\sigma_m$ and the corresponding strain $\gamma_m=\dot\gamma t_m$ both depend on the applied shear rate $\dot \gamma$ and on the waiting time $t_w$ between preshear and shear start-up: they remain roughly constant as long as $\dot\gamma$ is smaller than some critical shear rate $\dot\gamma_w\sim 1/t_w$ and they increase as weak power laws of $\dot \gamma$ for $\dot\gamma> \dot\gamma_w$ [...].Comment: 18 pages, 14 figures, accepted for publication in Soft Matte

Antidiabetic effects and mechanisms of action of γ-conglutin from lupin seeds

The glucose modulating properties of lupin have been attributed to its seed protein γ-conglutin. Here we explored the antidiabetic potential of γ-conglutin purified from lupin seeds in-vitro. To mimic the effects of an orally administered supplement, purified γ-conglutin was hydrolysed by gastrointestinal proteolytic enzymes and the resulting peptides evaluated for their antidiabetic effects in pancreatic β-cells and primary human skeletal muscle myotubes. γ-conglutin peptides did not promote insulin secretion in β-cells but elicited a potent insulin-mimetic action by activating insulin signalling pathways responsible for glycogen, protein synthesis, and glucose transport into myotubes. Additionally, the peptides potently suppressed the activity of DPP4 indicating their potential to increase the half-life of incretin hormones in circulation. These results substantiate the health benefits of consuming lupin seeds as part of a healthy diet and can drive the current market for lupins from primarily stockfeed, towards value-added lupin-based food products for human consumption

Craniofacial dysmorphology in 22q11.2 deletion syndrome by 3D laser surface imaging and geometric morphometrics: illuminating the developmental relationship to risk for psychosis

Persons with 22q11.2 deletion syndrome (22q11.2DS) are characterized inter alia by facial dysmorphology and greatly increased risk for psychotic illness. Recent studies indicate facial dysmorphology in adults with schizophrenia. This study evaluates the extent to which the facial dysmorphology of 22q11.2DS is similar to or different from that evident in schizophrenia. Twenty-one 22q11.2DS-sibling control pairs were assessed using 3D laser surface imaging. Geometric morphometrics was applied to 30 anatomical landmarks, 480 geometrically homologous semi-landmarks on curves and 1720 semi-landmarks interpolated on each 3D facial surface. Principal component (PC) analysis of overall shape space indicated PC2 to strongly distinguish 22q11.2DS from controls. Visualization of PC2 indicated 22q11.2DS and schizophrenia to be similar in terms of overall widening of the upper face, lateral displacement of the eyes/orbits, prominence of the cheeks, narrowing of the lower face, narrowing of nasal prominences and posterior displacement of the chin; they differed in terms of facial length (increased in 22q11.2DS, decreased in schizophrenia), mid-face and nasal prominences (displaced upwards and outwards in 22q11.2DS, less prominent in schizophrenia); lips (more prominent in 22q11.2DS; less prominent in schizophrenia) and mouth (open mouth posture in 22q11.2DS; closed mouth posture in schizophrenia). These findings directly implicate dysmorphogenesis in a cerebral-craniofacial domain that is common to 22q11.2DS and schizophrenia and which may repay further clinical and genetic interrogation in relation to the developmental origins of psychotic illness