An experimental study of near wall flow parameters in the blade end-wall corner region

The near wall flow parameters in the blade end-wall corner region is investigated. The blade end-wall corner region was simulated by mounting an airfoil section (NACA 65-015 base profile) symmetric blades on both sides of the flat plate with semi-circular leading edge. The initial 7 cm from the leading edge of the flat plate was roughened by gluing No. 4 floor sanding paper to artificially increase the boundary layer thickness on the flat plate. The initial flow conditions of the boundary layer upstream of the corner region are expected to dictate the behavior of flow inside the corner region. Therefore, an experimental investigation was extended to study the combined effect of initial roughness and increased level of free stream turbulence on the development of a 2-D turbulent boundary layer in the absence of the blade. The measurement techniques employed in the present investigation included, the conventional pitot and pitot-static probes, wall taps, the Preston tube, piezoresistive transducer and the normal sensor hot-wire probe. The pitot and pitot-static probes were used to obtain mean velocity profile measurements within the boundary layer. The measurements of mean surface static pressure were obtained with the surface static tube and the conventional wall tap method. The wall shear vector measurements were made with a specially constructed Preston tube. The flush mounted piezoresistive type pressure transducer were employed to measure the wall pressure fluctuation field. The velocity fluctuation measurements, used in obtaining the wall pressure-velocity correlation data, were made with normal single sensor hot-wire probe. At different streamwise stations, in the blade end-wall corner region, the mean values of surface static pressure varied more on the end-wall surface in the corner region were mainly caused by the changes in the curvature of the streamlines. The magnitude of the wall shear stress in the blade end-wall corner region increased significantly in the close vicinity of the corner line. The maximum value of the wall shear stress and its location from the corner line, on both the surfaces forming the corner region, were observed to change along the corner. These observed changes in the maximum values of the wall shear stress and its location from the corner line could be associated with the stretching and attenuation of the horseshoe vortex. The wall shear stress vectors in the blade end-wall corner region were observed to be more skewed on the end-wall surface as compared to that on the blade surface. The differences in the wall shear stress directions obtained with the Preston tube and flow visualization method were within the range in which the Preston tube was found to be insensitive to the yaw angle

Ion Adsorption Properties of Molybdenum Ferrocyanide, Tungsten Ferrocyanide & Multiloaded Molybdenum Ferrocyanide- Dowex Exchangers

800-80

Pelagic sharks by-catch in the tuna longline fishery of the Indian EEZ

Several species of pelagic and oceanic sharks are caught by the tuna longliners of FSI while surveying the oceanic tuna resources in the Indian EEZ. Though the sharks are not targeted species in tuna longlining, they constitute a major share of the catches. The sharks hooked could be, therefore, treated as by- catches or incidental catches of the tuna longline fisher

Energy as the basis of harvest index

Harvest index has become a character used in plant breeding programmes and in evaluation of responses to agronomic treatments. Donald defined harvest index as the ratio between weight of grains and the weight of total dry matter, and later described it as a measure of partitioning of photo-synthates (Donald, 1968)

Arithmetical Congruence Preservation: from Finite to Infinite

Various problems on integers lead to the class of congruence preserving functions on rings, i.e. functions verifying $a-b$ divides $f(a)-f(b)$ for all $a,b$. We characterized these classes of functions in terms of sums of rational polynomials (taking only integral values) and the function giving the least common multiple of $1,2,\ldots,k$. The tool used to obtain these characterizations is "lifting": if $\pi\colon X\to Y$ is a surjective morphism, and $f$ a function on $Y$ a lifting of $f$ is a function $F$ on $X$ such that $\pi\circ F=f\circ\pi$. In this paper we relate the finite and infinite notions by proving that the finite case can be lifted to the infinite one. For $p$-adic and profinite integers we get similar characterizations via lifting. We also prove that lattices of recognizable subsets of $Z$ are stable under inverse image by congruence preserving functions

Effect of irrigation on reproductive efficiency of bunch and spreading types of groundnut (Arachis hypogaea L.)

Groundnuts are mostly grown during the rainy season (kharif) in India. Most of the cultivation is without irrigation. Consequently the crop experiences water deficits of different intensities and durations, depending upon the rainfall distribution. Yields are poor under such conditions. In other leguminous species irrigation at flowering usually improves yield, if the pod development period coincides with a break in rainfall or water deficit (Khanna-Chopra, Koundal & Sinha, 1980). Thus, an understanding of reproductive behaviour and reproductive efficiency could be helpful in adjusting planting to coincide with favourable agroclimatic conditions. Alternatively, this understanding could help in scheduling irrigation

Long-Term Management of Esophageal Varices by Endoscopic Sclerotherapy (EST): A Review of 12 Years' Experience

A total of 566 patients with variceal bleeding caused by cirrhosis of the liver, noncirrhotic portal fibrosis (NCPF) and extrahepatic portal venous obstruction (EHO) were treated by repeated endoscopic injection sclerotherapy. This decreased rebleeding was evidenced by a reduction in mean bleeding risk factor and transfusion requirement. Both the factors were significantly (P < 0.001) decreased in all three groups of patients. Rebleeding occurred before eradication in 27.7% of patients with cirrhosis, 24.3% of those with NCPF, and 11% of those with EHO. Significantly more patients with cirrhosis and NCPF bled in comparison to EHO. Irrespective of the etiology, fewer patients of Child's A class bled than those of Child's B and C classes (P < 0.001). The median bleeding-free period was longer in patients with EHO than in those with cirrhosis (P < 0.05). This period was also significantly longer in Child's A class than in Child's B and the latter had a longer median bleeding-free period than Child's C class (P < 0.01). Variceal eradication was achieved in 80% of patients with cirrhosis, 87% of patients with NCPF, and 90% of patients with EHO. The success of variceal eradication was higher in EHO patients in contrast with patients with cirrhosis of the liver. Similarly, eradication was better in Child's A class patients than in Child's B and C class patients. Recurrence of varices and complications were not influenced by the Child's status or etiology of portal hypertension. The probability of survival at 10 years was higher in patients with EHO (88%) and NCPF (80%) than in patients with cirrhosis (50%). Similarly, patients with Child's A (88%) status survived longer than those with Child's B (42%) status, and patients with Child's B status had a longer survival than Child's C status patients (0%). Thus, endoscopic variceal sclerotherapy appears to be a useful procedure for the long-term management of patients after an esophageal variceal bleeding irrespective of the etiology of portal hypertension

Diagnosis of abnormal biliary copper excretion by positron emission tomography with targeting of (64)Copper-asialofetuin complex in LEC rat model of Wilson\u27s disease

Identification by molecular imaging of key processes in handling of transition state metals, such as copper (Cu), will be of considerable clinical value. For instance, the ability to diagnose Wilson\u27s disease with molecular imaging by identifying copper excretion in an ATP7B-dependent manner will be very significant. To develop highly effective diagnostic approaches, we hypothesized that targeting of radiocopper via the asialoglycoprotein receptor will be appropriate for positron emission tomography, and examined this approach in a rat model of Wilson\u27s disease. After complexing (64)Cu to asialofetuin we studied handling of this complex compared with (64)Cu in healthy LEA rats and diseased homozygous LEC rats lacking ATP7B and exhibiting hepatic copper toxicosis. We analyzed radiotracer clearance from blood, organ uptake, and biliary excretion, including sixty minute dynamic positron emission tomography recordings. In LEA rats, (64)Cu-asialofetuin was better cleared from blood followed by liver uptake and greater biliary excretion than (64)Cu. In LEC rats, (64)Cu-asialofetuin activity cleared even more rapidly from blood followed by greater uptake in liver, but neither (64)Cu-asialofetuin nor (64)Cu appeared in bile. Image analysis demonstrated rapid visualization of liver after (64)Cu-asialofetuin administration followed by decreased liver activity in LEA rats while liver activity progressively increased in LEC rats. Image analysis resolved this difference in hepatic activity within one hour. We concluded that (64)Cu-asialofetuin complex was successfully targeted to the liver and radiocopper was then excreted into bile in an ATP7B-dependent manner. Therefore, hepatic targeting of radiocopper will be appropriate for improving molecular diagnosis and for developing drug/cell/gene therapies in Wilson\u27s disease

Correlating the Energetics and Atomic Motions of the Metal-Insulator Transition of M1 Vanadium Dioxide

Materials that undergo reversible metal-insulator transitions are obvious candidates for new generations of devices. For such potential to be realised, the underlying microscopic mechanisms of such transitions must be fully determined. In this work we probe the correlation between the energy landscape and electronic structure of the metal-insulator transition of vanadium dioxide and the atomic motions occurring using first principles calculations and high resolution X-ray diffraction. Calculations find an energy barrier between the high and low temperature phases corresponding to contraction followed by expansion of the distances between vanadium atoms on neighbouring sub-lattices. X-ray diffraction reveals anisotropic strain broadening in the low temperature structure's crystal planes, however only for those with spacings affected by this compression/expansion. GW calculations reveal that traversing this barrier destabilises the bonding/anti-bonding splitting of the low temperature phase. This precise atomic description of the origin of the energy barrier separating the two structures will facilitate more precise control over the transition characteristics for new applications and devices.Comment: 11 Pages, 8 Figure