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91.
To investigate the effect of cellulase on increase of recovery of red bean starch precipitate, cellulases from Fusarium moniliforme were purified and applied to the production of red bean starch precipitate. Oneã-glucosidase, two filter paper degradation enzymes (FPase), one endo-ã-glucanase (endo-Cx) and one exo-ã-glucanase (exo-Cx) were purified by ammonium sulfate fractionation, gel filtration and ion-exchange chromatography. Optimum temperature and time of submersion of red beans for reduction of hardness was 50°C and 2 h. Maximum sedimentation rate of starch was obtained when the red bean was incubated in a mixture of 0.004 units/mL of FPase and 0.3 units/mL of CMCase, and maximum recovery of red bean starch precipitate was obtained with 0.004 units/mL of FPase and 0.2 units/mL of CMCase. Enzyme treatment reduced suspended solids about 40% in waste water compared with control. A little hydrolysis in cell wall, intercellular space and interstarch granular space was observed. 相似文献
92.
Scanning Calorimetric Behavior of Tilapia Myosin and Actin due to Processing of Muscle and Protein Purification 总被引:5,自引:0,他引:5
The thermal behavior of tilapia muscle proteins was investigated by differential scanning calorimetry at various stages in the processing of surimi and during purification of myosin and actin. A shift in the thermal transition of actin to lower temperature was observed and the enthalpies of denaturation for both actin and myosin decreased with further processing. Salt addition also induced shifts in denaturation transitions to lower temperatures and decreased enthalpies of denaturation. 相似文献
93.
ROSEMARY J. HASTINGS GRAHAM W. RODGER ROBIN PARK ANTHONY D. MATTHEWS EVELYN M. ANDERSON 《Journal of food science》1985,50(2):503-506
Differential Scanning Calorimetry (DSC) has been used to study the thermal properties of fish muscle proteins and to measure the extent of their denaturation under various processing conditions. Fish myosin was susceptible to denaturation by frozen storage and dehydration. Denaturation of certain fish proteins was partially reversible. Although fish myosin was very unstable, its thermal stability was found to increase in species adapted, to higher environmental temperatures. 相似文献
94.
The theory of magnetothermal convection of gases in homogeneous magnetic fields is developed from magnetogas-dynamic theory. Application is made to nonionized paramagnetic and diamagnetic gases between parallel vertical plates. An additive contribution to the natural thermal convection heat transfer results from the temperature dependence of the magnetic permeability of the gas. The result may be expressed parametrically in a dimensionless magnctoconvection number, which characterizes the magnetothermal contribution to the total heat transfer just as the Grashof number characterizes the natural thermal contribution. For oxygen gas at low pressure the magnetothermal contribution is shown to be proportional to p 3 H 2(ΔT)2 /ηT 5 where p is the gas pressure, H is the magnetic field strength, ΔT is the temperature difference between plates, η is the viscosity coefficient and T is the absolute temperature. 相似文献
95.
A new tool for the study of nucleate boiling heat transfer has been developed. Photographic etching was shown to be effective in the manufacture of copper lest surfaces containing precise arrays of artificial pits, with densities as high as 2742 pits/cm2.
The pits were shallow segments of spheres, with depth: diameter ratios on the order of 0.1. Pit diameters were on the order of 0.003 cm. Data showed that the pits significantly affected the characteristic boiling curves and critical fluxes for the surfaces studied while boiling Freon 113 at one atmosphere pressure.
Photoetching can be used in the future to produce a wide variety of test surface textures or site arrays. Careful control of such surface conditions may well lead to a better understanding of the nucleate boiling phenomena. 相似文献
96.
Churchil A. Antonyraj Jaewon Jeong Bora Kim Seunghan Shin Sangyong Kim Kwan-Young Lee Jin Ku Cho 《Journal of Industrial and Engineering Chemistry》2013,19(3):1056-1059
Selective oxidation of 5-hydroxymethyl-2-furfural (HMF) to 2,5-diformylfuran (DFF) toward industrial production was studied over Ru supported γ-alumina catalyst using molecular oxygen as an oxidant. From the solvents screening, considering recyclability after reaction, toluene was found to be the best solvent and gave maximum conversion of 99% with 97% DFF selectivity at 130 °C and 40 psi O2 pressure. Catalyst was washed with NaOH solution of pH = 12 to remove the adsorbed polymer impurities and then reused up to 5 cycles. The product could be purified by simple evaporation of the solvent, which could add advantage for industrial process. 相似文献
97.
K. R. CHU A. K. GANGULY V. L. GRANATSTEIN J. L. HIRSHFIELD S. Y. PARK J. M. BAIRD 《International Journal of Electronics》2013,100(4):493-502
A new type of travelling wave amplifier is proposed which features a slow wave structure and wide bandwidth operation. It is bused on the cyclotron interaction between a slow electromagnetic wave and helically moving electrons. Gain and bandwidths are calculated including the effect of beam velocity spread. It is shown that a bandwidth as high as 50% could be achieved with beam velocity spread?1%. 相似文献
98.
HEE-BOK KANG SUK-KYOUNG HONG HAE-CHAN PARK HEON-YONG CHANG KUN-WOO PARK JIN-HONG AHN 《Integrated ferroelectrics》2013,141(1):94-105
ABSTRACT For a longer working distance between passive tags and the reader, the ferroelectric based technologies are proposed in UHF (860–960 MHz) band transponder. The small ferroelectric capacitor layout area with a stacked capacitor structure over circuit region and a large dielectric permittivity of 250 to 500 and small 1T1C cell array layout area with simple 2T2C based reference scheme allow small chip size. The low operation voltage of 1.5 V to 2.0 V without high voltage boosting scheme also contribute to small power consumption and low cost. 相似文献
99.
SANGMIN SHIN JUNE MO KOO JUNE KEY LEE SUK PIL KIM CHOONG RAE CHO YOUNGSOO PARK 《Integrated ferroelectrics》2013,141(1):157-168
Pb(Zr,Ti)O3 (PZT) films grown on Ir electrodes by a metal-organic chemical vapor deposition (MOCVD) have suffered from high leakage and rough surface. We sputtered Pt and Ir simultaneously onto Ti/SiO2/Si substrates and formed Ir-Pt alloy bottom electrodes with various compositions. With an optimal composition of Ir and Pt, PZT films grown by MOCVD on this substrate showed smoother surface and suppressed leakage via the bottom interface. At the specific composition of Ir and Pt, two different phases seemed to be acquired. They constituted the electrodes and affected the PZT grain nucleation independently so that the grains with different origins grew and restrained the vicinal grains, and finally soothed the faceted-grain-formation. No fatigue was observed even in PZT on Ir-Pt alloy with much Pt content. 相似文献
100.
DONG‐KYU KIM WON‐WOONG PARK HO WON LEE SEONG‐HOON KANG YONG‐TAEK IM 《Journal of microscopy》2013,252(3):204-216
In this study, a rigorous methodology for quantifying recrystallization kinetics by electron backscatter diffraction is proposed in order to reduce errors associated with the operator's skill. An adaptive criterion to determine adjustable grain orientation spread depending on the recrystallization stage is proposed to better identify the recrystallized grains in the partially recrystallized microstructure. The proposed method was applied in characterizing the microstructure evolution during annealing of interstitial‐free steel cold rolled to low and high true strain levels of 0.7 and 1.6, respectively. The recrystallization kinetics determined by the proposed method was found to be consistent with the standard method of Vickers microhardness. The application of the proposed method to the overall recrystallization stages showed that it can be used for the rigorous characterization of progressive microstructure evolution, especially for the severely deformed material. 相似文献