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81.
82.
The Enskog modulus, bρ x, has been subjected to a generalized treatment to develop reduced state correlations for nonpolar and polar substances that exhibit hydrogen bonding. These correlations present relationships between 1 + bρx and ρR, the reduced density. For nonpolar substances, the PVT data of argon, nitrogen, methane, ethane, and carbon dioxide were used for the development of these relationships, which were found to depend on zc, the critical compressibility factor. PVT data for ammonia, methyl alcohol, and water yielded a different correlation, which is applicable to polar substances which exhibit hydrogen bonding. These relationships were found to depend on the parameter, β = (Tb-Tm)/M, which quantitatively describes the extent of hydrogen bonding for polar compounds. 相似文献
83.
An Agent-Based Approach for Scheduling Multiple Machines 总被引:2,自引:1,他引:1
We present a new agent-based solution approach for the problem of scheduling multiple non-identical machines in the face of sequence dependent setups, job machine restrictions, batch size preferences, fixed costs of assigning jobs to machines and downstream considerations. We consider multiple objectives such as minimizing (weighted) earliness and tardiness, and minimizing job-machine assignment costs. We use an agent-based architecture called Asynchronous Team (A-Team), in which each agent encapsulates a different problem solving strategy and agents cooperate by exchanging results. Computational experiments on large instances of real-world scheduling problems show that the results obtained by this approach are significantly better than any single algorithm or the scheduler alone. This approach has been successfully implemented in an industrial scheduling system. 相似文献
84.
R. R. Reddy Y. Nazeer Ahammed K. Rama Gopal P. Abdul Azeem T. V. R. Rao 《Optical Materials》1999,12(4):425-428
A new method for calculating the optical basicity, electronic polarizability and oxygen electronegativity of oxides and oxysalts has been evaluated based on the concept of average electronegativity given by Asokamani and Manjula. The estimated parameters are in good agreement with the Duffy values. The results are also discussed in relation to the nature of bonding. It is suggested that the impurity of average electronegativity in predicting different parameters is well emphasised. 相似文献
85.
Ramón Moreira Francisco Chenlo María D. Torres Beatriz Rama 《Food and Bioproducts Processing》2013,91(1):7-13
Chestnut flour doughs were prepared using chestnut air-dried at 45, 65, and 85 °C with constant load density (8.0 ± 0.6 kg/m2). Mixing curves of doughs using Mixolab® device showed that chestnut flour doughs dried at 85 °C needed more water absorption to reach the target consistency, (1.1 ± 0.07 Nm). Thermorheological properties were evaluated by means of a controlled stress rheometer. All tested doughs showed shear-thinning behaviour in the steady-shear tests (0.001–1 s?1). Oscillatory (1–100 rad s?1 at 0.1% strain), temperature sweep (30–90 °C) and creep-recovery (loading 50 Pa for 60 s) tests showed that flour doughs from chestnuts dried at 85 °C provide interesting properties, particularly remarkable elasticity that is associated with starch gelatinisation. Experimental data were described using various rheological models. 相似文献
86.
Prashant Kumar Rai Ashok Kumar Pathak Somenath Ghatak Geeta Watal Awadhesh Kumar Rai Rama Jayasundar 《Sensing and Instrumentation for Food Quality and Safety》2013,7(3):114-121
Although plants have long been a major source of medicine, there is renewed interest in studying the phytochemistry and use of herbal formulations. This paper reports spectroscopic analysis using Laser Induced Breakdown Spectroscopy (LIBS) of a polyherbal formulation, whose antidiabetic activity has also been demonstrated on rat models. LIBS analysis revealed the presence of elements such as Na, K, Mg, Ca, H, O and N. The antidiabetic study showed that amongst the four doses studied (50, 100, 150 and 200 mg/kg bw), the dose of 150 mg/kg bw registered the maximum fall in Blood Glucose Level (BGL) in both normal and diabetic (sub and mild) rats in the Glucose Tolerance Test (GTT) study—normal rats (22 %), sub-diabetic (36.6 %) and mild-diabetic (39 %). The dose of 150 mg/kg also showed the maximum fall of 23.7 % and 22 % in BGL during fasting BGL and GTT studies of normal rats, respectively. The formulation also showed significant antioxidant activity assessed using in vitro assays. The study validates for the first time the therapeutic use of an antidiabetic polyherbal formulation. 相似文献
87.
Axial dispersion coefficients (E) in the liquid phase have been measured by unsteady tracer response methods in a 15 cm internal diameter reciprocating plate bubble column, using air and water in countercurrent and cocurrent flow. The operating variables studied were amplitude (0.6–1.27 cm) and frequency (0–5 Hz) of reciprocation, and the superficial velocities of the liquid and gas phases and the spacing between plates. Three types of plate were studied; conventional Karr-type plates with perforation diameters 1.43 cm, plates with smaller (0.635 cm) perforations, and single-perforation (doughnut) plates with internal diameter 7 cm. Measured values of E ranged from about 1 cm2/s to a maximum of 116 cm2/s. In general, the plates with 0.635 cm perforations gave the smallest values of E while the largest values of E were obtained with the doughnut plates, due to vortex ring shedding. The single liquid phase data for the three types of plate were approximately consistent with the correlation of Stevens and Baird (1990). The gas-liquid flow results were interpreted in terms of several different hydrodynamic effects. 相似文献
88.
89.
M. Grujicic G. Arakere A. Hariharan B. Pandurangan 《Journal of Materials Engineering and Performance》2012,21(4):437-449
High-strength aluminum and titanium alloys with superior blast/ballistic resistance against armor piercing (AP) threats and
with high vehicle light-weighing potential are being increasingly used as military-vehicle armor. Due to the complex structure
of these vehicles, they are commonly constructed through joining (mainly welding) of the individual components. Unfortunately,
these alloys are not very amenable to conventional fusion-based welding technologies [e.g., gas metal arc welding (GMAW)]
and to obtain high-quality welds, solid-state joining technologies such as friction-stir welding (FSW) have to be employed.
However, since FSW is a relatively new and fairly complex joining technology, its introduction into advanced military-vehicle-underbody
structures is not straight forward and entails a comprehensive multi-prong approach which addresses concurrently and interactively
all the aspects associated with the components/vehicle-underbody design, fabrication, and testing. One such approach is developed
and applied in this study. The approach consists of a number of well-defined steps taking place concurrently and relies on
two-way interactions between various steps. The approach is critically assessed using a strengths, weaknesses, opportunities,
and threats (SWOT) analysis. 相似文献
90.
Bhari Mallanna Nagaraja Aytam Hari PadmasriBurri David Raju Kamaraju Seetha Rama Rao 《International Journal of Hydrogen Energy》2011,36(5):3417-3425
Cu-MgO is found to be an efficient catalyst for the coupling reaction of furfural (FAL) hydrogenation and cyclohexanol (CyOH) dehydrogenation. This process is not only efficient in compensating the thermodynamic equilibrium constraints in the cyclohexanol dehydrogenation and improving the yields towards cyclohexanone but also is a economical route for the synthesis of furfuryl alcohol (FFA) and cyclohexanone (Cyone) as the process do not need any external pumping of hydrogen. The effect of incorporation of various promoters viz., Co, Zn, Fe, Cr, Pd and Ni in Cu-MgO over its activity towards this coupling reaction has been studied. Incorporation of Cr in Cu-MgO catalyst is found be an advantageous in enhancing the yields of both FFA and Cyone. All other promoters though found to show higher activity for the individual reactions of FAL hydrogenation and CyOH dehydrogenation, failed to do the same in their coupling reaction. The stabilization of active species (Cu+/Cu0) by Cr which also seem to increase the synergetic interaction between Cu and MgO as observed from higher dispersion of copper (from XRD results) and easier reducibility of copper oxide (from TPR results) seem to be the factors behind its higher activity over other promoted catalysts. 相似文献