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1.
The effects of key parameters on the preparation and regeneration of protoplast from the β-carotene-producing fungus Blakeslea trispora were discussed in this paper, including the combination of various enzymes, mycelial age, digesting time and temperature,
pH value, osmotic stabilizers, pretreatment, culture medium and culture method. Under the condition of mixed enzymes in osmotic
stabilizer (0.6 M NaCl) combined with 2% lysozyme, 3% cellulase and 3% snailase, the highest protoplast yield, as high as
7.48×106 protoplasts/mL, was obtained when mycelial age was 60 h at pH 5.0–6.0 with digesting for 14–16 h at 28 °C. After
purification of the obtained protoplasts, they were regenerated in PDA regenerative medium using bilayer plate culture method.
To validate the usability of the protoplasts, a novel plasmid with green fluorescent protein (GFP) was used in transformation
for easy visual observation. The results showed that the protoplasts prepared by the optimized method were active and applicable
in further gene manipulation experiments.
This work was presented at 13
th
YABEC symposium held at Seoul, Korea, October 20–22, 2007. 相似文献
2.
Particulate is the most problematic emission from diesel engines. To comply with environmental regulations, these engines are often equipped with particulate traps, which must be regenerated frequently for the sake of efficiency. The regeneration is commonly achieved by rising the temperature in the trap till the particulate self-ignites. However, this method implies energy losses and thermal shocks in the trap. Alternatively, catalysts and additives have been recently considered for reducing the ignition temperature of particulate, but these techniques suffer from poisoning and undesirable byproducts. The present experimental study shows that the ignition temperature of particulate from seed-derived oils (SO) and from blends of SO with diesel fuel oil (DO) can be lower than that of particulate from neat DO. If substantiated by more extensive studies, such finding could have noteworthy implications on the future of fuels and traps. 相似文献
3.
利用热天平测试了CO、H2还原饱和脱硫剂微孔内Fe2(SO4)3的起始反应温度及还原速率,用X射线衍射法分析了反应中间产物及最终产物.实验结果表明,脱硫剂还原法再生的反应温度较传统热分解法低约200℃,CO作再生脱硫剂的还原气体优于H2,CO还原脱硫剂内Fe2(SO4)3的反应级数为0.87,活化能为142.9kJ/mol. 相似文献
4.
On the use of graphical method to determine the targets of single-contaminant regeneration recycling water systems 总被引:2,自引:0,他引:2
Water system integration with regeneration recycling can reduce freshwater consumption and wastewater discharge to the maximum extent. In this paper, by analyzing the limiting composite curve of a single-contaminant water system, a method is proposed to construct the optimal water supply line for regeneration recycling. Accordingly the targets for regeneration recycling water systems are obtained. The targets in sequence are the minimum freshwater consumption (the minimum wastewater discharge), the minimum regenerated water flowrate, and the optimal regeneration concentration. The post-regeneration concentration is taken to be fixed in the sequential targeting procedure. The interactions of these targets are analyzed, and formulas for calculating these targets are proposed. The results show that for a single-contaminant regeneration recycling water system, the minimum freshwater consumption is determined by the shape of the limiting composite curve below the post-regeneration concentration. The optimal regeneration concentration is defined as the minimum regeneration concentration at the minimum freshwater consumption and the corresponding minimum regenerated water flowrate. The minimum regenerated water flowrate and the optimal regeneration concentration are both related to the geometrical features of the limiting composite curve of the water-using system and to the post-regeneration concentration. The optimal regeneration concentration has no direct relationship with the pinch concentration. 相似文献
5.
The thermal regeneration of activated carbons loaded with p-nitrophenol (PNP) and other aromatic compounds was studied using a thermal balance. After pyrolysis of the adsorbates in nitrogen at 700°C, the residues were gasified with oxygen at 415 to 500°C or with steam at 840 to 920°C. Residues from PNP were several times more reactive to oxygen than the base carbons and also showed greater chemisorption of oxygen. For steam gasification, only small differences between spent and fresh carbons were found. 相似文献
6.
7.
An efficient strategy to approximate the failure probability function in structural reliability problems is proposed. The failure probability function (FPF) is defined as the failure probability of the structure expressed as a function of the design parameters, which in this study are considered to be distribution parameters of random variables representing uncertain model quantities. The task of determining the FPF is commonly numerically demanding since repeated reliability analyses are required. The proposed strategy is based on the concept of augmented reliability analysis, which only requires a single run of a simulation-based reliability method. This paper introduces a new sample regeneration algorithm that allows to generate the required failure samples of design parameters without any additional evaluation of the structural response. In this way, efficiency is further improved while ensuring high accuracy in the estimation of the FPF. To illustrate the efficiency and effectiveness of the method, case studies involving a turbine disk and an aircraft inner flap are included in this study. 相似文献
8.
Farhad Shir Catherine Mavriplis Lawrence H. Bennett Edward Della Torre 《International Journal of Refrigeration》2005,28(4):1082
Results of a room temperature magnetic refrigeration test bed and an analysis using a computational model are presented. A detailed demonstration of the four sequential processes in the transient magnetocaloric regeneration process of a magnetic material is presented. The temperature profile during the transient approach to steady state operation was measured in detail. A 5 °C evolution of the difference of temperature between the hot end and the cold end of the magnetocaloric bed due to regeneration is reported. A model is developed for the heat transfer and fluid mechanics of the four sequential processes in each cycle of thermal wave propagation in the regenerative bed combined with the magnetocaloric effect. The basic equations that can be used in simulation of magnetic refrigeration systems are derived and the design parameters are discussed. 相似文献
9.
10.
数据挖掘是应用一系列技术从大型数据库或数据仓库中提取人们感兴趣的信息和知识,已在零售业得到了广泛的应用,却在流程过程中使用较少。针对某石化企业的连续重整过程,利用决策树归纳法,建立反应器温度波动模型,对实时数据进行预测,对于引起反应器温度波动较大的操作提出建议性的决策树规则,从而达到改善控制效果和提高装置运行平稳性的目的。 相似文献