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51.
Alginate Encapsulated Bifidobacteria Survival in Mayonnaise 总被引:2,自引:0,他引:2
Bifidobacterium bifidum and Bifidobacterium infantis were added to mayonnaise as either free cells or encapsulated. The survival of bifidobacteria and their effect on mayonnaise quality were evaluated. The viability of free cells disappeared after 2 wk; however, encapsulated B. bifidum survived well for 12 and B. infantis for 8 wk. Mayonnaise containing encapsulated bifidobacteria had lower total bacterial counts compared to other treatments. Yeast and mold started to appear after 12 wk of storage in mayonnaise containing encapsulated bifidobacteria and after 6 wk with other treatments (control, cells free of bifidobacteria). Mayonnaise containing encapsulated bifidobacteria had higher titratable acidity and lower TBA values than other treatments. Sensory properties of mayonnaise were improved by the addition of encapsulated bifidobacteria. 相似文献
52.
HAMID LAZAN ZAINON MOHD. ALI AI'ANI MOHD FALEHATUN NAHAR 《Journal of food science》1987,52(5):1286-1292
The effect of water stress (excessive water loss) on postharvest quality during storage of tropical leafy vegetables Brussica junceu L. and Amaranthus caudatus L. at ambient (24°/28°C) and low temperature (2°/4°C) regimes has been investigated. Exposed, nonsealed B. juncea and A. caudutus leaves lost water rapidly during storage at either temperature regime resulting in accelerated decrease in leaf turgidity (wilting), chlorophyll, ascorbic acid and soluble protein content, and an increase in amino acids, in the stressed leaves. Alleviation of water stress by sealing the leaves with thin plastic film restricted chlorophyll, soluble protein and ascorbic acid loss, particularly when the leaves were cooled, and maintained their turgidity. Both leafy vegetables appeared tolerant to chilling injury. 相似文献
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54.
Phenoloxidase (PO), pro-PO [1] and pro-PO [2], isolated from cuticular extracts of early premolt spiny lobster, resolved into doublets of molecular weights 156, 151, and 96.0, 93 kD, respectively. Trypsin-activated forms of pro-PO [1] and pro-PO [2] were 123 and 83.6 kD, respectively. Apparently melanosis of shell and hyperdermal tissue in lobsters was related to stage of molt. The pro-PO forms were activated in vitro by extracts of molting fluid which is secreted into the cuticle just before molt, and the activated PO co-migrated in SDS-PAGE with the endogenously activated PO. The molting fluid was hypothesized to be the source of the natural activator(s) of pro-PO. 相似文献
55.
In recent years research on parallel machine scheduling has received an increased attention. This paper considers minimisation of total tardiness for scheduling of n jobs on a set of m parallel machines. A spread-sheet-based genetic algorithm (GA) approach is proposed for the problem. The proposed approach is a domain-independent general purpose approach, which has been effectively used to solve this class of problem. The performance of GA is compared with branch and bound and particle swarm optimisation approaches. Two set of problems having 20 and 25 jobs with number of parallel machines equal to 2, 4, 6, 8 and 10 are solved with the proposed approach. Each combination of number of jobs and machines consists of 125 benchmark problems; thus a total for 2250 problems are solved. The results obtained by the proposed approach are comparable with two earlier approaches. It is also demonstrated that a simple GA can be used to produce results that are comparable with problem-specific approach. The proposed approach can also be used to optimise any objective function without changing the basic GA routine. 相似文献
56.
KAVEH KAZEMIKIA FAHIMEH BONABI ALI ASADPOORCHALLO MAJID SHOKRZADEH 《Bulletin of Materials Science》2016,39(2):457-462
The goal of this work is to study the effect of high magnetic pulses on electrical property of carbon nanotube–polypyrrole (CNT–PPy) composites with different CNT concentrations. CNT–PPy composites are produced in fractions of 1, 5 and 9 wt%. During the polymerization process, the CNTs are homogeneously dispersed throughout the polymer matrix in an ultrasonic bath. Nanocomposite rods are prepared. After exposure to 30 magnetic pulses, the resistivity of the rods is measured. The surface conductivity of thin tablets of composites is studied by 4-probe technique. The magnitude of the pulsed magnetic field is 10 Tesla with time duration of 1.5 ms. The results show that after applying 30 magnetic pulses, the electrical resistivity of the composites decreases depending on the concentration of CNTs in the composites. The orientation of CNTs is probed by atomic force microscopy (AFM) technique. AFM images approved alignment of CNT–polymer fibres in the magnetic field. We found that the enhancement in the electrical properties of CNT–PPy composites is due to rearrangement and alignment of CNTs in a high magnetic field. The stability of nano-composites is studied by Fourier transform infrared spectroscopy. 相似文献
57.
Riaz KHAN Sehrish SHAKIR Ahmad ALI Muhammad Khawar AYUB Moazzam NAZIR Zia UR-REHMAN Abdul QAYYUM Muhammad Athar NAVEED Sarfraz AHMAD Zahoor AHMAD Rafaqat ALI Shahid HUSSAIN 《等离子体科学和技术》2021,23(8):53-61
GLAss Spherical Tokamak(GLAST-Ⅲ) is a spherical tokamak with an insulating vacuum vessel that has a unique single-passage capability for incident microwaves.In this work,electron cyclotron resonance heating(ECRH)-assisted plasma pre-ionization in GLAST-Ⅲ is explored for three radio-frequency(RF) polarizations(the O-,X-,and M-modes) at different toroidal-field(TF) strengths and filled gas pressures.The optimum hydrogen pressure is identified for efficient plasma pre-ionization.A comparison of the plasma pre-ionizations initiated by the O-,X-,and M-modes shows prominent differences in the breakdown time,location,and wave absorption.In the case of O-mode polarization,microwave absorption occurs for a relatively shorter duration,resulting in a bell-shaped electron-temperature(T_e) temporal profile.Microwave absorption is dominant in the case of the X-mode,leading to a broader T_e temporal profile.The M-mode discharge contains features of both the X-and O-modes.Efficient plasma pre-ionization is achieved in the X-mode polarization for the intermediate TF strengths(with a central toroidal magnetic field B_0=0.075 T).Traces of the electron-number density show a similar tendency,as revealed by T_e.These results suggest that the X-mode is the best candidate for efficient plasma pre-ionization at low filled gas pressures(~10~(-2) Pa) in small tokamaks. 相似文献
58.
Output-feedback control with almost-disturbance-decoupling property—a singular perturbation approach
ALI SABERI 《International journal of control》2013,86(5):1705-1722
For square invertible and minimum-phase linear time-invariant systems, a high-gain observer-based control law is proposed. This control law provides internal stability for the closed-loop system and has the almost-disturbance-decoupling properly: that is, the influence of the disturbances on the controlled output can be made arbitrarily small. 相似文献
59.
MOHAMMAD R EDALATIAN MOHAMMAD B HABIBI NAJAFI ALI MORTAZAVI BALTASAR MAYO 《International Journal of Dairy Technology》2012,65(1):81-89
Ninety‐five isolated strains of Lactic acid bacteria (LAB) were identified from Lighvan cheese. The LAB evolution showed the dominance of lactococci and lactobacilli in the first stage and substitution of these genera by enterococci at the end of ripening. The most predominant strains were Enterococcus faecium (22.44%), Lactococcus lactis ssp. lactis (20.4%), Lactobacillus plantarum (18.36%) and E. faecalis (14.28%), respectively. Eleven and 51 different carbohydrate fermentation profiles were observed according to API 20 STREP and API 50 CH, respectively. API 20 STREP dendogram showed identical fermentation profiles of some E. faecalis and E. faecium strains, indicating that these strains might be well adapted to the whole cheese manufacture. 相似文献
60.