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951.
First principles calculations were performed to investigate the elastic, electronic and thermal properties of 14% cubic yttria-stabilized zirconia (YSZ) using the pseudo potential plane-wave method within the gradient generalized approximation (GGA) for the exchange and correlation potential. Computed lattice constant parameters are in good agreement with the available experimental results. The three independent elastic constants were computed by means of the stress-strain method, indicating that 14% cubic YSZ is a mechanically stable structure. From the knowledge of the elastic constants, a set of related properties, namely bulk, shear modulus, Young’s modulus, sound velocity, Debye temperature, thermal capacity and minimum thermal conductivity are numerically estimated in the frame work of the Voigt-Reuss-Hill approximation for YSZ polycrystalline. The calculated bulk modulus, shear modulus, Young’s modulus, sound velocity, Debye temperature, thermal capacity and minimum thermal conductivity are in reasonable agreement with the available experimental and theory data. Density of states, charge density and Mulliken population analysis show that the 14% cubic YSZ is covalent and possess ionic character.  相似文献   
952.
Wang J  Zhao J  Qin C  Di J  Rauf A  Jiang H 《Optics letters》2012,37(7):1211-1213
We present a novel method for dynamical measurement of the ternary diffusion by using digital holographic interferometry based on wavelength and angular multiplexing techniques. Two laser beams with different wavelengths (λ1=532 nm and λ2=473 nm) are used for the ternary diffusion measurement, and they are adjusted to make corresponding interference fringes in orthogonal directions on the CCD target. The orthogonal splitting of the fringes enables the spatial frequencies of each wavelength to be filtered separately in the Fourier spectrum of the hologram. Finally, they are reconstructed to obtain the molar concentration. This method is also suitable for two-phase diffusion measurement.  相似文献   
953.
This work addresses a static analysis of functionally graded material (FGM) plates using higher order shear deformation theory. In the theory the transverse shear stresses are represented as quadratic through the thickness and hence it requires no shear correction factor. The material property gradient is assumed to vary in the thickness direction. Mori and Tanaka theory (1973) [1] is used to represent the material property of FGM plate at any point. The thermal gradient across the plate thickness is represented accurately by utilizing the thermal properties of the constituent materials. Results have been obtained by employing a C° continuous isoparametric Lagrangian finite element with seven degrees of freedom for each node. The convergence and comparison studies are presented and effects of the different material composition and the plate geometry (side-thickness, side–side) on deflection and temperature are investigated. Effect of skew angle on deflection and axial stress of the plate is also studied. Effects of material constant n on deflection and the temperature distribution are also discussed in detail.  相似文献   
954.
The thermal decomposition of potassium bromate (KBrO3) has been studied as a function of particle size, in the range 53?C150???m, by isothermal thermogravimetry at different temperatures, viz. 668, 673, 678, and 683?K in static air atmosphere. The theoretical and experimental mass loss data are in good agreement for the thermal decomposition of all samples of KBrO3 at all temperatures studied. The isothermal decomposition of all samples of KBrO3 was subjected to both model fitting and model-free (isoconversional) kinetic methods of analysis. Isothermal model fitting analysis shows that the thermal decomposition kinetics of all the samples of KBrO3 studied can be best described by the contracting square equation. Contrary to the expected increase in rate followed by a decrease with decrease in particle size, KBrO3 shows a regular increase in rate with reduction in particle size, which, we suggest, is an impact of melting of this solid during decomposition.  相似文献   
955.
Duchenne Muscular Dystrophy (DMD) is a common, inherited, incurable, fatal muscle wasting disease caused by deletions that disrupt the reading frame of the DMD gene such that no functional dystrophin protein is produced. Antisense oligonucleotide (AO)-directed exon skipping restores the reading frame of the DMD gene, and truncated, yet functional dystrophin protein is expressed. The aim of this study was to assess the efficiency of two novel rigid, cationic carotenoid lipids, C30-20 and C20-20, in the delivery of a phosphorodiamidate morpholino (PMO) AO, specifically designed for the targeted skipping of exon 45 of DMD mRNA in normal human skeletal muscle primary cells (hSkMCs). The cationic carotenoid lipid/PMO-AO lipoplexes yielded significant exon 45 skipping relative to a known commercial lipid, 1,2-dimyristoyl-sn-glycero-3-ethylphosphocholine (EPC).  相似文献   
956.
We isolated and examined two endophytic fungi for their potential to secrete phytohormones viz. gibberellins (GAs) and indoleacetic acid (IAA) and mitigate abiotic stresses like salinity and drought. The endophytic fungi Phoma glomerata LWL2 and Penicillium sp. LWL3 significantly promoted the shoot and allied growth attributes of GAs-deficient dwarf mutant Waito-C and Dongjin-beyo rice. Analysis of the pure cultures of these endophytic fungi showed biologically active GAs (GA1, GA3, GA4 and GA7) in various quantities. The cultures of P. glomerata and Penicillium sp. also contained IAA. The culture application and endophytic-association with host-cucumber plants significantly increased the plant biomass and related growth parameters under sodium chloride and polyethylene glycol induced salinity and drought stress as compared to control plants. The endophytic symbiosis resulted in significantly higher assimilation of essential nutrients like potassium, calcium and magnesium as compared to control plants during salinity stress. Endophytic-association reduced the sodium toxicity and promoted the host-benefit ratio in cucumber plants as compared to non-inoculated control plants. The symbiotic-association mitigated stress by compromising the activities of reduced glutathione, catalase, peroxidase and polyphenol oxidase. Under stress conditions, the endophyte-infection significantly modulated stress through down-regulated abscisic acid, altered jasmonic acid, and elevated salicylic acid contents as compared to control. In conclusion, the two endophytes significantly reprogrammed the growth of host plants during stress conditions.  相似文献   
957.
Budu is a famous Malaysian fish sauce, usually used as seasoning and condiment in cooking. Budu is produced by mixing fish and salt at certain ratio followed by fermentation for six months in closed tanks. In this study, four commercial brands of Budu were analyzed for their chemical properties (pH, salt content and volatile compounds). The pH of Budu samples ranged from 4.50-4.92, while the salt (NaCl) content ranged between 11.80% and 22.50% (w/v). For tentative identification of volatile flavor compounds in Budu, two GC columns have been used, DB-WAX and HP-5MS. A total of 44 volatile compounds have been detected and 16 were common for both columns. 3-Methyl-1-butanol, 2-methylbutanal, 3-methylbutanal, dimethyl disulfide, 3-(methylthio)-propanal, 3-methylbutanoic acid and benzaldehye have been identified as the aroma-active compounds in Budu due to their lower threshold values.  相似文献   
958.
959.
A novel sensor network based on optical time-division multiplexing (OTDM) is proposed and demonstrated for simultaneous sensing of long-period grating (LPG) sensor array with overlapping spectra. A star network is configured by pairing a circulator with each of the LPG sensors. Experiments are conducted by measuring the changes of surrounding refractive index at different sensors, which show excellent agreement between the demultiplexed and pristine transmission spectrum of the LPG sensors.  相似文献   
960.
Tannery effluent (sludge, wastewater) is treated by natural way. The waste sludge has been taken for two treatment process. The alkali chemicals are neutralized by pyroligneous acid which is obtained by pyrolysis process of wood. This sludge is sent out for drying. The dried sludge contains some crack pattern formation. Photographs were used to record two sludge cracking surfaces. Experiment has been performed to study the fracture pattern formation in thin film sludge. We studied changes of crack surface of a sludge by image analysis and also assessed applicability of fractal scaling to crack surfaces. The calculated crack surface dimension shows that the fracture surface exhibit fractal structure. Image size was 256 × 256 pixels. MFA (multifractal analysis) was carried out to the method of moments, i.e., the probability distribution was estimated for moments ranging from ?150 < q < 150 and the generalized dimension were calculated from the log/log slope of the probability distribution for the respective moments over box sizes. Generalized dimension D(q) were attained for this box size range, which are capable of characterizing heterogeneous spatial crack structure. Multifractal spectra analyzed two fracture surface of the image and results were indicated that the width of spectra increases due to pyroligneous acid. Multifractal method is sensitive enough to measure the fracture distribution and can be seen as a different approach for changing research of crack images of manure sludge drying.  相似文献   
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