Effect of fluoride on root resorption of autogenous dental replants. Clinical study

One hundred and fifty teeth were replanted using three procedures and it was found that greater success occurred in teeth when the periodontal membrane had been removed prior to treatment with two per cent sodium fluoride solution before replantation. Retention of the periodontal membrane on the root surface of the alveolar bone was not significant in the success of replants and reduced the success of those replants which were treated with fluoride. Endodontic procedures were found to be time consuming without contributing to the success of the end result.     

Bearing influenced rotor dynamics

This paper presents a brief summary of the influence of journal bearings in machinery with special reference to rotor dynamic problems. The journal bearings considered are Newtonian, non-Newtonina and magnetohydrodynamic and their influence on the critical speeds and stability of rotors is investigated     

The effect of L-dopa and chlorpromazine on prolactin and growth hormone secretion in normal women

The time course of simultaneous changes in prolactin (PRL) and growth hormone secretion in response to a single dose of L-dopa and chlorpromazine was determined in normal women. L-Dopa induced greater, but shorter (30 minutes), growth hormone release than concomitant suppression of PRL secretion. The PRL peak following chlorpromazine occurred at the same time as the nadir of PRL after L-dopa (3.5 hours). The quantity of PRL release inhibited by L-dopa equaled the amount of PRL secretion during the period of rebound, suggesting L-dopa inhibits PRL release, but not synthesis, by the pituitary.     

Regularity of dapsone intake by leprosy patients attending urban treatment centre

Dapsone/Creatinine in urine ratios were determined in statistically randomised samples of 965 leprosy patients attending out-patient department of Acworth Leprosy Hospital and 44 inmates of the Hospital. The percentage of irregularity in DDS treatment was found in 43 and 22.6 respectively in out-patients and inmates of the Hospital. The need to assess the possible response for irregularity in treatment is stressed and the hazard of infectious cases remaining without treatment or with incomplete treatment is pointed out.     

Effect of Al2O3 nano-additives on the performance and emission characteristics of jatropha and pongamia methyl esters in compression ignition engine

Nano-additives can be added to biodiesel blends to improve its performance through better fuel properties. The present study investigated the effects of Al₂O₃ nano-additives on B20 blends of pongamia and jatropha biodiesel in a vertical single cylinder direct injection compression ignition engine. The fuel properties have been determined for all fuel samples with and without additives addition. The engine study was conducted to analyse the performance and emission characteristics of the blends with and without the additives at varying loads. The emissions from the biodiesel blends were comparatively lesser than that of normal diesel. B20 blend of pongamia biodiesel with additive has shown better performance. Additive-added biodiesel blends show a significant reduction in NO_x emission.     

Hot Workability and Flow Characteristics of Aluminum-5 wt.% B4C Composite

Flow behavior of aluminum-5 wt.% boron carbide (Al-B₄C) composite was investigated by carrying out compression tests over a range of strain rates (10^?4-10⁰ s^?1) and temperatures (200-500 °C). The flow stress data obtained from these tests at true strain 0.5 were used to develop processing map. The stable and instable flow regimes in the map were characterized by the microstructural examination using Scanning Electron Microscopy and Electron Backscattered Diffraction. The optimum condition for processing of Al-5%B₄C composite was found to lie between 425 and 475 °C at the strain rate of around 10^?4 s^?1. A strain-compensated Sellars-McG Tegart constitutive equation was established to model high-temperature deformation behavior of the material.     

The deformation of the chill in experiments to determine the interfacial heat transfer coefficient during casting solidification

Interfacial heat transfer coefficients during casting solidification are often measured in experiments in which unidirectional heat transfer is assumed. Finite element modelling of the chill in these experiments has shown that the chill surface deforms elastically into a convex shape, the extent of which generally decreases with time. Examples from several different unidirectional solidification experiments are given. The deformation of the chill surface was also calculated with the assumption of nonuniform temperature boundary conditions. The deformation of the chill could be such that only in the central region of the casting-chill interface would the two surfaces be in contact, with a localised gap between them at their periphery. The extent of this deformation could be sufficient that heat transfer through the interface may not be unidirectional as assumed in the experiment and, depending on the location of the thermocouples placed close to the interface, the accuracy of the heat transfer coefficients calculated from the data collected at these points may therefore be affected.     

Experimental Study of Flow Patterns,Pressure Drop,and Flow Instabilities in Parallel Rectangular Minichannels

Abstract

Flow boiling heat transfer in parallel minichannels and microchannels is one of the solutions proposed for cooling high heat flux systems. The associated increase in the pressure drop poses a problem that needs to be studied in detail before the small diameter channels can be implemented in practical systems. The pressure drop fluctuations and the flow instability in a network of parallel channels connected by a common header also need to be addressed for the stable operation of flow boiling systems. The current work focuses on studying the flow patterns, pressure drop fluctuations, and flow instabilities in a set of six parallel rectangular minichannels, each with 333μm in hydraulic diameter. Deionized and degassed water was used for all the experiments. The pressure fluctuations are recorded and signal analysis is performed to find the dominant frequencies and their amplitudes. These pressure fluctuations are then mapped to their corresponding flow patterns observed using a high speed camera. The results help us to relate pressure fluctuations to different flow characteristics and their effect on flow instability.     

Complexity of the AGV shortest path and single-loop guide path layout problems

The guide path layout is one of the most important variables in the design of automated guided vehicle systems (AGVS). Many alternative guide path configurations have been proposed in previous research. Two of the simplest are the shortest path and shortest single-loop configurations. However, the optimal solutions to these two problems have not been easy to obtain. In this paper, we show why by proving the NP-completeness of these problems using graph theoretic methods.