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排序方式： 共有2062条查询结果，搜索用时 15 毫秒
981.
Ashok K. Shrestha Tharalinee Ua-arak Benu P. Adhikari Tony Howes Bhesh R. Bhandari 《International Journal of Food Properties》2013,16(3):661-673
Spray drying behavior of orange juice concentrate with various levels of maltodextrin (DE 6) was studied. Five combinations of orange juice concentrate and maltodextrin (25:75, 30:70, 35:65, 40:60, and 50:50) were spray dried at 160 and 65°C inlet and outlet temperatures, respectively. The product recovered with 50% maltodextrin concentration was sticky and only 20% powder was recovered. The recovery of orange juice powder increased as the amount of maltodextrin in powders increased. The particle size and bulk density remained almost the same in all except in 50% maltodextrin powder which was slightly larger and more dense. The moisture content of spray dried powders was high and desiccated before measuring glass transition temperature. The anhydrous spray dried powders showed increased Tg values with increasing maltodextrin concentration, from 66°C in 50% maltodextrin to 97°C in 75% maltodextrin containing powders. The glass rubber transition (Tg-r) values of all the products measured using novel Thermal Mechanical Compression Test (TMCT) were higher than Tg values measured by DSC; the difference in values increased with increase in maltodextrin concentration. 相似文献
982.
M Rayner V Ciolfi B Maves P Stedman G
S Mittal 《Journal of the science of food and agriculture》2000,80(6):777-782
A soy protein film coating was developed and evaluated to reduce fat transfer in deep‐fried foods during frying. Soy protein isolate solutions (10% SPI) with 0.05% gellan gum as plasticizer cooled after being held at 80 °C for 20 min provided suitable films. There was a significant fat reduction (55.12 (±6.03)%db) between fried uncoated and coated discs of doughnut mix. The same films were used on potato fries. Some panellists observed a slight difference between the coated and uncoated fries but many preferred the coated fries over the uncoated ones. Penetration test on potato fries showed no significant difference between the texture of coated (SPI with gellan gum) and the uncoated fried samples. A solution of 10% SPI with 0.05% gellan gum is recommended for coating foods to reduce fat intake during deep‐fat frying. © 2000 Society of Chemical Industry 相似文献
983.
Jayashree Arcot Stephanie Wong Ashok K Shrestha 《Journal of the science of food and agriculture》2002,82(12):1365-1368
The changes in undeconjugated and total folate content of soybean during various stages of tempeh and soymilk preparation were studied. Total folate was extracted by the tri‐enzyme technique. The ratio of total folate to undeconjugated folate was compared in all samples. Raw soybeans used for tempeh and soymilk preparation contained 4.04 and 4.50 mg total folate kg?1 respectively. Soaking and boiling soybean caused a significant loss of folate during tempeh and soymilk preparation. Leaching was identified as the major cause of folate loss, as soaking and cooking waters were found to contain a large amount of folate. Rhizopus fermentation of boiled soybean caused an increase of 68 and 100% in undeconjugated and total folate contents respectively. Frying reduced the folate content of tempeh significantly. Milling of boiled soybean in soymilk preparation significantly reduced the undeconjugated folate content of blanched soybean but increased the total folate. UHT treatment of soymilk caused a loss of 9 and 14% of undeconjugated and total folates respectively. The total folate content of deep‐fried tempeh and soymilk was 2.35 and 2.76 mg kg?1 respectively. Analysed values are expressed on a dry weight basis. © 2002 Society of Chemical Industry 相似文献
984.
The proposed method of linear time invariant system order reduction is based on multipoint step response matching for both pole and zero evaluation of the reduced order system (ROS). Depending on the number of zeros and poles of the ROS, the number of points is selected on the time axis of the unit step response such that the unknown poles and zeros can be determined by solving a set of non-linear equations using Newton's method. Numerous examples have been solved using the proposed technique and the results are encouraging. 相似文献
985.
Ashok Bera Haiyang Peng James Lourembam Youde Shen Xiao Wei Sun T. Wu 《Advanced functional materials》2013,23(39):4977-4984
Integrating materials with distinct lattice symmetries and dimensions is an effective design strategy toward realizing novel devices with unprecedented functionalities, but many challenges remain in synthesis and device design. Here, a heterojunction memory made of wurtzite ZnO nanorods grown on perovskite Nb‐doped SrTiO3 (NSTO) is reported, the electronic properties of which can be drastically reconfigured by applying a voltage and light. Despite of the distinct lattice structures of ZnO and NSTO, a consistent nature of single crystallinity is achieved in the heterojunctions via the low‐temperature solution‐based hydrothermal growth. In addition to a high and persistent photoconductivity, the ZnO/NSTO heterojunction diode can be turned into a versatile light‐switchable resistive switching memory with highly tunable ON and OFF states. The reversible modification of the effective interfacial energy barrier in the concurrent electronic and ionic processes most likely gives rise to the high susceptibility of the ZnO/NSTO heterojunction to external electric and optical stimuli. Furthermore, this facile synthesis route is promising to be generalized to other novel functional nanodevices integrating materials with diverse structures and properties. 相似文献
986.
987.
A method of simultaneous field‐ and flow‐directed assembly of anisotropic titania (TiO2) nanoparticle films from a colloidal suspension is presented. Titania particles are oriented by an alternating (ac) electric field as they simultaneously advect towards a drying front due to evaporation of the solvent. At high field frequencies (ν > ～25 kHz) and field strengths (E > 300 V cm?1), the particles orient with their major axis along the field direction. As the front recedes, a uniform film with thicknesses of 1–10 µm is deposited on the substrate. The films exhibit a large birefringence (Δn ≈ 0.15) and high packing fraction (? = 0.75 ± 0.08), due to the orientation of the particles. When the frequency is lowered, the particle orientation undergoes a parallel–random–perpendicular transition with respect to the field direction. The orientation dependence on field frequency and strength is explained by the polarizability of ellipsoidal particles using an interfacial polarization model. Particle orientation in the films also leads to anisotropic mechanical properties, which are manifested in their cracking patterns. In all, it is demonstrated that the field‐directed assembly of anisotropic particles provides a powerful means for tailoring nanoparticle film properties in situ during the deposition process. 相似文献
988.
In this paper we consider a redundant system with two identical units, providing for partial failure mode and two types of repairs for a failed unit. Failure and repair time are assumed to follow general distribution. Applying the regenerative theory in Markov-renewal process, several reliability characteristics of interest to system designers are obtained. 相似文献
989.
990.
Evolutionary response analysis of Duffing oscillator using Gaussian equivalent linearization in wavelet based time-frequency frame work is presented here. Cubic （i.e., odd type） non-linearity associated with stiffness and damping is modeled. The goal of this research is to develop the mathematical model of an equivalent linear system which is applicable for different non-stationary input processes （i.e., either summation of amplitude modulated stationary orthogonal processes or digitally simulated non-stationary processes）. The instantaneous parameters of the ELTVS （equivalent linear time varying system） are evaluated by minimizing the error between the displacements of non-linear and equivalent linear systems in wavelet domain. For this purpose, three different basis functions （i.e., Mexican Hat, Morlet and a modified form of Littlewood-Paley） are used. The unknown parameters （i.e., natural frequency and damping） of the ELTVS are optimized in stochastic least square sense. Numerical results are presented for different types of input to show the applicability and accuracy of the proposed wavelet based linearization technique. 相似文献