High-temperature emissivities of copper, aluminum, and silver

[[abstract]]Using a transient calorimetric technique, the total hemispherical emissivities Eh of very pure copper, aluminum, and silver have been measured at various temperatures in the range 335-1100'K. By carrying out measurements on a sphere, a thin circular disk, and a thin square plate all made of the same copper sample, it is shown that the measured (, is practically independent of the shape of the specimen. Measured E,, values of Cu, Al, and Ag show considerable departure from the theoretical predictions of Davisson and Weeks and the data of previous investigators. Eh data are presented in tabular form at 20'K intervals for all three materials in the range 400-1000'K.[[notice]]補正完畢[[booktype]]紙

Influence of analysis and design models on minimum weight design

The results of numerical experiments designed to illustrate how the minimum weight design, accuracy, and cost can be influenced by: (1) refinement of the finite element analysis model and associated load path problems, and (2) refinement of the design variable linking model are examined. The numerical experiments range from simple structures where the modelling decisions are relatively obvious and less costly to the more complex structures where such decisions are less obvious and more costly. All numerical experiments used employ the dual formulation in ACCESS-3 computer program. Guidelines are suggested for creating analysis and design models that predict a minimum weight structure with greater accuracy and less cost. These guidelines can be useful in an interactive optimization environment and in the design of heuristic rules for the development of knowledge-based expert optimization systems

DEVELOPMENT AND VALIDATION OF CHROMATOGRAPHIC METHOD FOR THE SIMULTANEOUS ESTIMATION OF OLMESARTAN MEDOXOMIL, AMLODIPINE BESYLATE, CILNIDIPINE IN COMBINATION TABLET DOSAGE FORM

Objective: To develop and validate a simple, sensitive and isocratic reverse phase high performance liquid chromatography (RP-HPLC) method for the simultaneous determination of olmesartan medoxomil (OLM), amlodipine besylate (AML) and cilnidipine (CIL) in pharmaceutical tablet formulation.Methods: In this work we have taken 2 combinations, combination 1-OLM & AML and combination 2-OLM & CIL. HPLC analysis was carried out by using reverse phase isocratic elution with a C 18 column and a mobile phase of 0.05 M ammonium acetate, acetonitrile and methanol in the ratio of 30:50:20, v/v, pH was adjusted to 7.3. Detection of the analyte was achieved by using UV detector at 240 nm.Results: The retention time of olmesartan medoxomil, amlodipine besylate and cilnidipine were 2.2, 3 and 4.5 minutes respectively. Linearity of the method was found to be in the concentration range of 10-100µg/ml for olmesartan medoxomil, 5-50µg/ml for amlodipine and 10-100µg/ml for cilnidipine. The correlation coefficient value was greater than 0.999 for all the analytes.Conclusion: The method was validated as per ICH guidelines and is applied for the estimation of these components simultaneously in pharmaceutical tablet formulation.Â

Equivalent widths of atomic lines in sunspot spectra

Equivalent widths of 82 Cr I lines, 70 Fe 1 lines, and 74 Ti I lines are measured in the spectra of four sunspots of average area 55 millionths of the visible hemisphere of the sun. Separate curves of growth for Cr I, Fe t, and Ti I are constructed. Excitation temperatures of 4030° ± 80° , 4200° ± 150° , and 3800° ± 100° are obtained for Cr I, Fe I, and Ti I, respectively

Mechanical Properties of Randomly Oriented Calotropis Gigantea Fiber-Reinforced Phenol Formaldehyde Biocomposites

Mechanical properties such as tensile, flexural and impact, of randomly oriented Calotropis Gigantea Fiber (CGF) -reinforced Phenol Formaldehyde (PF) biocomposites were studied based on the five different fiber loadings (10, 20, 30, 40, and 50 vol%) and three different fiber lengths (3, 9, and 15 mm). The critical fiber length and optimum fiber loading were identified with the maximum level of mechanical properties in this composite. The fractured surfaces of composites after testing were studied by scanning electron microscope (SEM). The results revealed that the addition of CGFs is improving the mechanical properties of the PF composite. The properties of composites reach the properties of the neat resin sample at 20 vol% of all the cases. The critical fiber length and the optimum fiber loading to obtain the maximum mechanical properties were identified as 9 mm and 40 vol% respectively. Experimental tensile property values were compared with theoretical values and found to be in good agreement

Device Free Localisation Techniques in Indoor Environments

The location estimation of a target for a long period was performed only by device based localisation technique which is difficult in applications where target especially human is non-cooperative. A target was detected by equipping a device using global positioning systems, radio frequency systems, ultrasonic frequency systems, etc. Device free localisation (DFL) is an upcoming technology in automated localisation in which target need not equip any device for identifying its position by the user. For achieving this objective, the wireless sensor network is a better choice due to its growing popularity. This paper describes the possible categorisation of recently developed DFL techniques using wireless sensor network. The scope of each category of techniques is analysed by comparing their potential benefits and drawbacks. Finally, future scope and research directions in this field are also summarised