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21.
22.
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
23.
蒋熙 《中国服装(北京)》2005,(23):b0010-b0025
1995年4月下旬,中国服装设计师协会主办了首届中国“十佳”服装设计师评选活动。在符合条件的上万名设计师当中选拔出15名候选人,进而评选出十位最佳设计师,被赋予“十佳”称号。首届获得十佳称号的设计师为张肇达、刘洋、王新元、吴海燕、马可、于泽正、崔游、陈红、刘丽丽和罗亚平等十人。 相似文献
24.
针对碳酸盐岩气藏部分气井生产效能低的状况,决定在长庆气田下古生界尝试开展加砂压裂重复改造试验,以期提高低产、低效气井的产量,延长气田稳产期。通过潜心研究、精细设计及现场质检监控,优选了4口老井进行加砂压裂重复改造现场试验。从试验结果来看,虽然只有1口井取得明显的改造效果,但4口井加砂压裂施工都是成功的,说明对碳酸盐岩气藏实施加砂压裂是可以实现的,但在选井思路和压裂工艺方面还有待探索和研究。 相似文献
25.
Average consensus in networks of dynamic agents with switching topologies and multiple time-varying delays 总被引:5,自引:0,他引:5
In this paper, we discuss average consensus problem in undirected networks of dynamic agents with fixed and switching topologies as well as multiple time-varying communication delays. By employing a linear matrix inequality method, we prove that all the nodes in the network achieve average consensus asymptotically for appropriate communication delays if the network topology is connected. Particularly, several feasible linear matrix inequalities are established to determine the maximal allowable upper bound of time-varying communication delays. Numerical examples are given to demonstrate the effectiveness and the sharpness of the theoretical results. 相似文献
26.
Wei Li Zhang Wei Pan Bin Luo Xi Hua Zou Meng Yao Wang 《Photonics Technology Letters, IEEE》2008,20(9):712-714
A theoretical construction of one-to-many (OTM) and many-to-one (MTO) chaos synchronization communications using semiconductor lasers is presented. One center laser provides strong injections (strong link) to other side lasers, and the side lasers also provide weak injections (weak link) to the center one. Simulation results show that the side lasers synchronize with the center laser through injection-locking. In addition, messages transmitted via the strong links or the weak links experience strong chaos pass filtering, enabling us to realize OTM and MTO communications. 相似文献
28.
29.
An innovative method for modelling biological processes under anaerobic conditions is presented and discussed. The method is based on titrimetric and off-gas measurements. Titrimetric data is recorded as the addition rate of hydroxyl ions or protons that is required to maintain pH in a bioreactor at a constant level. An off-gas analysis arrangement measures, among other things, the transfer rate of carbon dioxide. The integration of these signals results in a continuous signal which is solely related to the biological reactions. When coupled with a mathematical model of the biological reactions, the signal allows a detailed characterisation of these reactions, which would otherwise be difficult to achieve. Two applications of the method to the enhanced biological phosphorus removal processes are presented and discussed to demonstrate the principle and effectiveness of the method. 相似文献
30.
A systematic approach for synthesising gyrator-C active transformers using MOS transistors is presented. The topology of gyrator-C active inductors and their characteristics are briefly reviewed first. This is followed by the development of ideal gyrator-C active transformers, where only the capacitor loads of the transconductors synthesising active transformers are considered. The self and mutual inductances of both the primary and secondary windings of active transformers are investigated in detailed. Non-ideal gyrator-C active transformers are developed with the consideration of both the resistance and capacitance loads of transconductors. The intrinsic relation between the self and mutual inductances is derived. The configuration of gyrator-C active transformers with multiple primary and secondary windings is also developed. The proposed active transformers offer large and tunable self and mutual inductances with virtually no silicon area requirement. Several practical implementations of the proposed active transformers have been realised in TSMC-0.18 mum 1.8 V CMOS technology and analysed using SpectreRF with BSIM3v3 device models. Simulation results on voltage transfer characteristics, self and mutual inductances, quality factors, stability, the effect of process variations, and noise are presented. The application of the proposed active transformers is exemplified using a 1.6 GHz active transformer quadrature oscillator. 相似文献