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91.
Lavanya S. SaravanaKumar N. M. Vijayakumar V. Thilagam S. 《Mobile Networks and Applications》2019,24(4):1152-1159
Mobile Networks and Applications - In recent days, management of keys in a group has become a significant part of data communication. The textual and alphanumerical passwords used for security... 相似文献
92.
D. N. Khanna D. L. Durham F. Seyedi P. H. Lu T. Perera 《Polymer Engineering and Science》1992,32(20):1500-1508
Novolak resins provide the best overall performance for “g” and “i”-line photoresists. There is a continuing need for advanced novolak designs that will provide improved lithographic, thermal, and etch characteristics that may be reproducibly synthesized. A novolak synthesis process was developed using the solution condensation technique. Cresol mixtures with m-cresol and 3,5-xylenol at specific ratios provide reproducible novolaks with controlled molecular weights. In order to achieve high thermal and etch performance, while retaining photospeed and resolution characteristics, three basic approaches were investigated: (1) increase in molecular weight, which produces novolaks with Tg ranging from 120 to 130°C with relatively slow dissolution rates; (2) incorporation of multi-hydroxyphenols such as resorcinol to tailor the dissolution rate, resolution, thermal, etch, and adhesion characteristics; (3) partial esterification of multi-hydroxy novolaks giving a Tg range of 140 to 150°C. Lithographic evaluation of the novolak resins was performed by formulating with a 2,1,4-diazonaphthoquinone (DNQ) sensitizer. Results on resin synthesis, molecular weights, lithographic, thermal, and etch characteristics are discussed. 相似文献
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95.
A novel humidity sensor using the structure Cu-Al2O3-Al has been developed for high humidity applications. The capacitance and conductance characteristics of the sensor, measured as a function of humidity at different frequencies, are given. The temporal drift in the characteristics is also investigated. A theory describing the operational behaviour of this device is proposed based on the humidity-sensitive spreading conductance of the oxidised copper film. This ingenious technique has a remarkable multiplicative action on the high humidity sensitivity. 相似文献
96.
Oxidation studies have been carried out on NiCrAl-base alloys in air and air containing 1% sulphur dioxide at 1000°C. The alloys used were in the cast, forged and single-crystalline form. There was considerable difference in the oxidation behavior of the as-cast alloy and that of forged alloy, when the environment contained sulphur dioxide. In the absence of the latter, the behavior of the two alloys was not very different. The oxidation behavior of the single crystals was also very similar to that of the cast and forged alloys, when the atmosphere was oxidizing. A few single-crystalline alloys, however, underwent catastrophic oxidation when about 1% sulphur dioxide gas was present, in a manner similar to that of the cast alloy. Oxidation tests at 1000°C as well as detailed scale analysis indicated that the different microstructure, especially large difference in grain size was probably the main reason for the large difference in their oxidation behavior. 相似文献
97.
Various thermal analysis studies were conducted to characterize metallic glasses. The methods used, namely differential scanning calorimetry, dilatometry, dynamic mechanical analysis and thermomagnetometry, are shown to be useful for studying thermally induced phenomena. Examples covered demonstrate the usefulness of thermal techniques in evaluating structural relaxation. Curie temperature, glass transition, and devitrification processes. A basis of understanding structural relaxation and the glass transition is discussed in terms of a diagram of enthalpy against temperature. 相似文献
98.
The fracture behaviour of a glass-fabric-reinforced epoxy composite has been investigated experimentally. Load-displacement curves for single-edge-notched specimens were obtained on an MTS system and the J-integral evaluated through its energy rate interpretation. Jc, the critical value of the J-integral, obtained directly for a0/w > 0·4 and that obtained through an extrapolation procedure for a0/w < 0·4 compare quite well. Jc appears to be independent of crack length for specimen widths between 15 and 45 mm. Jc for ±45° specimens is less than half that for 0/90 specimens. 相似文献
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100.
P. Nema A. Chelani C. S. P. Ojha Arvind Kumar P. Khanna 《Canadian Metallurgical Quarterly》2004,130(12):1534-1542
An artificial neural network (ANN) model is developed to study the correlation of data with reference to various wastewater pollution parameters (biochemical oxygen demand, chemical oxygen demand, suspended solids, NH4, PO4) using two scales of experiments viz. column lysimeter and a pilot soil aquifer treatment (SAT) system for wastewater renovation in India. A unique feature of the study is that the primary treated wastewater was directly applied to SAT system for renovation in contrast to the secondary treated effluent used in most of the other studies that have been reported. The analysis of data using ANN as a tool indicates that the column lysimeter data are useful for design of SAT systems and it is possible to predict the effluent quality for SAT system based on the inputs from lysimeter experiments. The study highlights the utility of column lysimeter studies for evolving design parameters for a full-scale SAT system thereby obviating the need for pilot SAT studies which are site specific, time consuming, and expensive. Thus, the study suggests that the experimental data from lysimeter studies at a particular site can be used to predict performance of field-scale SAT systems without going in for actual experimentation. Further, the field data from one site could be utilized for design of SAT systems at other locations provided the climatic and hydrogeological conditions viz. soil matrix characteristics and wastewater characteristics, etc., are similar. 相似文献