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101.
102.
Variation in oil content and fatty acid profiles of a native Australian biodiesel feedstock species Calophyllum inophyllum were studied in two different fruiting periods (winter 2008 and autumn 2009) and in three different northern Queensland provenances (Cardwell, Townsville, Yeppoon). Oils were extracted by standard n-hexane double extraction and fatty acid profiles were determined by ISO 5508 and 5509 methods using gas chromatography. C. inophyllum provenances have demonstrated a significant periodic variation in oil content and fatty acid profile, and as a result alter the quality of fatty acid methyl esters (biodiesel). FAP of majority of kernel oil sources were found to vary significantly (P < 0.05) with seasonal variation in temperature and longterm average rainfall. 相似文献
103.
The present paper reports the composition dependence of pre-exponential factor and activation energy of non-isothermal crystallization in amorphous alloys of Cu x Ti100?x system using differential scanning calorimeter (DSC) technique. The applicability of Meyer-Neldel relation between the pre-exponential factor and activation energy of non-isothermal crystallization for amorphous alloys of Cu-Ti system was verified. 相似文献
104.
Strain-induced martensitic transformation in stainless steels: A three-dimensional phase-field study
A three-dimensional elastoplastic phase-field model is developed to study the microstructure evolution during strain-induced martensitic transformation in stainless steels under different stress states. The model also incorporates linear isotropic strain hardening. The input simulation data is acquired from different sources, such as CALPHAD, ab initio calculations and experimental measurements. The results indicate that certain stress states, namely uniaxial tensile, biaxial compressive and shear strain loadings, lead to single variant formation in the entire grain, whereas others, such as uniaxial compressive, biaxial tensile and triaxial strain loadings, lead to multivariant microstructure formation. The effects of stress states, strain rate as well as temperature on the mechanical behavior of steels are also studied. The material exhibits different yield stresses and hardening behavior under different stress states. The equivalent stress is higher at low strain rate, whereas a higher elongation is obtained at high strain rate. The deformation temperature mainly affects the hardening behavior of the material as well as the transformation, i.e. martensite volume fraction decreases with increasing temperature. Some of the typical characteristics of strain-induced martensite, such as the formation of thin elongated martensite laths, shear band formation and nucleation of martensite in highly plasticized areas, as well as at shear band intersections, are also observed. 相似文献
105.
R. Muthukumaran Subhash C. Mishra 《International Journal of Heat and Mass Transfer》2008,51(9-10):2418-2432
Transient response of a planar participating medium subjected to a short-pulse diffuse or collimated radiation is investigated. The pulse-width of the radiation is of the order of a nano-second. Short-pulse radiation can have a step or a Gaussian temporal variation. The homogenous participating medium with diffuse-gray boundaries is absorbing and scattering. The north boundary of the participating medium can be under the influence of a pulse train consisting of 1–4 pulses. The analysis is done using the finite volume method. Effects of the extinction coefficient and the scattering albedo on transmittance and reflectance signals are studied for a train of pulses. Unlike the previous studies with a single-pulse, a train of pulses provides more useful information about the medium. 相似文献
106.
Umaid Singh Paleti Venkateswara Rao Nukala Subrahmanyam Kulbhushan Saxena 《Journal of the science of food and agriculture》1993,61(4):395-400
Eight newly developed pigeonpea genotypes (ICPL 87, ICPL 151, ICPL 270, ICPL 366, ICPL 87051, ICPL 87063, ICPL 87067, and ICPV 1), and the two controls (BDN 2 and C 11) were analysed for cooking quality parameters and chemical composition, including amino acids and minerals. Protein quality was evaluated by determining the true protein digestibility, biological value, net protein utilisation (NPU), and utilisable protein. These genotypes differed significantly (P < 0–01) in the dhal cooking time. Sensory properties of dhal of these genotypes were found to be within the acceptable range, even though there were considerable differences among genotypes. Dhal protein, calcium, magnesium, zinc, and iron contents of these genotypes showed noticeable differences. Calcium content of ICPL 87067 was the highest (85-6 mg per 100 g) and of ICPL 87 the lowest (54-4 mg per 100 g) indicating large differences among the newly developed genotypes. No noticeable differences in sulphur-containing amino acids of these genotypes were observed. NPU was the highest (65–4%) for ICPL 366 and the lowest (56–6%) for ICPL 270 and ICPL 87067 indicating significant (P < 0–01) differences among genotypes studied. 相似文献
107.
Much of the work in modeling and computer simulation of spinodal decomposition has been done for binary systems. This work attempts to carry out the analysis of spinodal decomposition in ternary polymer‐solvent‐nonsolvent systems, where the solvent is the monomer used to produce the polymer and the nonsolvent is the major component. Various experimental methods are used to determine values of the parameters of the ternary version of the Cahn‐Hilliard equation of spinodal decomposition, such as cloudpoint experiments, time‐resolved light scattering in the ternary system, and morphological development of polymer membranes formed during the early stages spinodal decomposition. The combination of these experimental methods and computer simulation work shows the validity of the assumptions made in characterizing spinodal decomposition in ternary polymer systems of interest. 相似文献
108.
Binary liquid-liquid-equilibria data for several aniline-paraffin and furfural-paraffin systems have been taken. These data along with data for other aniline-hydrocarbon and furfural-hydrocarbon systems from literature have been correlated using UNIFAC model. The UNIFAC group interaction parameters have been found to have a linear temperature dependence. The CH2 groups in cyclo and non cyclo paraffins require different interaction parameters. It was also found that a scaling of the combinatorial term is necessary for higher molecular weight hydrocarbons. 相似文献
109.
Baldwyn Torto Ahmed Hassanali Kailash N. Saxena Sagary Nokoe 《Journal of chemical ecology》1991,17(1):67-78
Phagostimulatory responses of third-instar larvae ofChilo Partellus to phenolic components identified in an ethyl acetate extract of the leaf whorls of 3-week-old plants ofSorghum bicolor cultivar IS 18363 were studied in no-choice bioassays. The major components in the extract were identified as 4-hydroxybenzaldehyde and 4-hydroxybenzoic acid, with 4-hydroxy-3-methoxycinnamic acid, 3,4-dihydroxycinnamic acid, and 4-hydroxycinnamic acid present in minor amounts. All but 4-hydroxycinnamic acid were stimulatory at the doses tested. 4-Hydroxybenzaldehyde was more stimulatory than other potential biogenetic analogs. Hydroxybenzoic acids generally elicited greater feeding response than cinnamic acids, and the pattern of oxygen substitution in the benzene ring was related to bioactivity. 相似文献
110.
K. Kapoor S. V. Swamy N. Saratchandran V. K. Saxena G. Malakondaiah B. P. Kashyap 《Journal of Failure Analysis and Prevention》2002,2(3):65-70
This paper reports the details of a test method that uses elements of elastic-plastic fracture mechanics to assess fracture
resistance of zirconium (Zr)-2.5 wt.% niobium (Nb) pressure tubes for a pressurized heavy water reactor. The fracture properties
were evaluated on curved specimens, and the effect of certain trace elements on the fracture properties was determined. Significant
reduction of trace impurities, produced by using four-stage melting practices rather than the conventional two-stage process,
was observed to cause considerable improvement in the fracture resistance of the alloy. Scanning electron microscopy (SEM)
of the fracture surfaces of the test specimens confirmed this observation. 相似文献