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61.
U Mohanty 《Canadian Metallurgical Quarterly》1986,34(6):4993-4999
62.
A scalable new mathematical model based on the principles of Process Integration has been developed for the analysis of multiple effect evaporator (MEE) systems. It uses the concepts of stream analysis, temperature path and internal heat exchange for the formulation of the model equations. In addition to the above concepts, the model also takes into account the variable physico‐thermal properties of steam/vapor, condensate and liquor, while simulating the MEE system. The present model consists of a set of linear equations and does not present any stability or oscillation problems during solution as is generally seen in the case of models that are based on sets of nonlinear equations. The model equations are automatically generated through a computer program and the model was run for three different liquor and flow sequences to prove its utility. The results obtained are compared with published models. 相似文献
63.
The nano-scaled Sn–3.5Ag solder was prepared successfully by a supernatant process in the present study. The morphology of the nano-particle was investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. It was found from the SEM micrographs that the average diameter of the particle was 137 nm with a standard deviation of ±5 nm. From the TEM studies it was revealed that the particles aggregated into larger particles and the shape of the elongated particles were irregular. The composition of the alloy was also measured by an electron probe microanalyzer (EPMA) and energy dispersive spectroscopy (EDS), qualitatively and quantitatively. The eutectic element, Ag with a weight percentage of 3.5%, was found to be homogenous over all of the particles. Furthermore, the microstructure of the Sn–3.5Ag alloy was identified by X-ray diffraction. It was found that the trace element, Ag was dissolved in the matrix, a tetragonal system, without an intermetallic phase. 相似文献
64.
In this paper, we propose a methodology which helps customers buy products through the Internet. This procedure takes into account the customer's level of desire in the product attributes, which are normally fuzzy, or in linguistically defined terms. The concept of fuzzy number will be used to measure the degree of similarities of the available products to that of the customer's requirements. The degrees of similarities so obtained over all the attributes give rise to the fuzzy probabilities and hence the fuzzy expected values of availing a product on the Internet as per the customer's requirement. Attribute‐wise the fuzzy expected values are compared with those of the available products on the Internet and the product that is closest to the customer's preference is selected as the best product. The multi‐attribute weighted average method is used here to evaluate and hence to select the best product. 相似文献
65.
66.
Banerjee Amit Mishra P. R. Mohanty Ashok Chakravarty K. Das Biswas R. Sahu R. Chakravarty S. 《国际煤炭科学技术学报(英文)》2016,3(2):97-103
International Journal of Coal Science & Technology - Mineral phase characterization and thorough understanding of its transformation behavior during combustion are imperative to know the... 相似文献
67.
The following article from the Journal of Applied Polymer Science, “Mechanical and thermal properties enhancement of polycarbonate nanocomposites prepared by melt compounding” by Sanjay K. Nayak, Smita Mohanty, and Sushanta K. Samal, published online on 7 April 2010 in Wiley Online Library (J. Appl. Polym. Sci. 2010 , 117, 2101; http://onlinelibrary.wiley.com/doi/10.1002/app.31222/full ), has been retracted by agreement between the authors, the journal's editors, and Wiley Periodicals, Inc. The retraction has been agreed due to significant overlap with respect to another article, “Effect of hydrogen bonding on the rheology of polycarbonate/organoclay nanocomposites,” by Kyung Min Lee, and Chang Dae Han, published online on 19 June 2003 in Polymer ( 2003 , 44, 4573). 相似文献
68.
Studies in the expansion behaviour of tapered fluidized bed systems are important for specifying the height of the bed. Data have been obtained on the expanded heights of tapered fluidized beds and bed expansion ratios for spherical and non-spherical particles have been calculated. Based on dimensional analysis, models have been developed as a function of geometry of tapered bed, static bed height, particle diameter, density of solid and gas and superficial velocity of the fluidizing medium. The data used to derive the models cover a wide range of operating conditions, with varying fluidization velocities. Effects of static bed height, particle diameter, density, tapered angle and superficial gas velocity over minimum fluidization velocity on bed expansion ratios have been investigated experimentally. A comparison has been made between the calculated values of bed expansion ratios using proposed models and the experimental data. It has been seen that calculated values by models agree well with the experimental values. Models have also been compared with literature data of conventional bed and found its applicability at higher gas velocities with good accuracy. 相似文献
69.
Sanjeeb K. Rout Prema K. Barhai Ela Sinha Ali Hussain W. Kim III 《International Journal of Applied Ceramic Technology》2010,7(Z1):E114-E123
The effect of grain orientation on the dielectric and electrical properties of SrBi4Ti4O15 ceramics are studied by impedance and modulus spectroscopy. The degree of orientation calculated from the X-ray diffraction pattern is found to be 94.2% along the c-axis of the crystal structure. The ratio of permittivity along the perpendicular to parallel direction is found to be ∼2.5 at the Curie temperature. The nonsuperimposition of the normalized Z″ and M″ versus frequency plot revealed that the conduction is localized and deviate from ideal Debye-like behavior. The conduction mechanism has been explained on the basis of jump relaxation model. 相似文献
70.
In this study, the effect of poly(ethylene glycol) (PEG) on the preparation of Poly(lactic acid) (PLA)/PEG blend and its nanocomposites by melt intercalation method were investigated. The PEG having molecular weight of 6,000 g/mol used with various concentrations (0, 10, 15, 20, 25, 30 wt%) in the preparation of PLA/PEG blend. Again, two types of commercialized organoclay [cloisite 93A (C93A) and cloisite 30B (C30B)] were used for the preparation of blend nanocomposites. With the incorporation of PEG into PLA the tensile strength and modulus decreases, whereas the percentage elongation and impact strength increases predominantly. Further, the PLA/PEG blend nanocomposites showed improved tensile strength and modulus with the addition of oraganoclays into the blend. Scanning electron microscopy (SEM) reveals the surface and miscibility study of the PLA/PEG blend. The effect of clay interaction in the PLA/PEG blend nanocomposites were also studied by using wide angle X‐ray diffraction (WAXD) and transmission electron microscopy (TEM). Dynamic mechanical analysis (DMA) was used to investigate the viscoelastic behavior of the blends and its nanocomposites. Differential scanning calorimetry (DSC) study reveals decreased glass transition temperature in case of PLA/PEG blend. The thermal stability of the blend and its nanocomposites were being studied by using thermogravimetric analysis (TGA). POLYM. COMPOS., 35:283–293, 2014. © 2013 Society of Plastics Engineers 相似文献