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61.
Jiwon Kim Hyeoncheol Francis Son Sungmin Hwang Gyeongtaek Gong Ja Kyong Ko Youngsoon Um Sung Ok Han Sun-Mi Lee 《International journal of molecular sciences》2022,23(9)
Yarrowia lipolytica, the non-conventional yeast capable of high lipogenesis, is a microbial chassis for producing lipid-based biofuels and chemicals from renewable resources such as lignocellulosic biomass. However, the low tolerance of Y. lipolytica against furfural, a major inhibitory furan aldehyde derived from the pretreatment processes of lignocellulosic biomass, has restricted the efficient conversion of lignocellulosic hydrolysates. In this study, the furfural tolerance of Y. lipolytica has been improved by supporting its endogenous detoxification mechanism. Specifically, the endogenous genes encoding the aldehyde dehydrogenase family proteins were overexpressed in Y. lipolytica to support the conversion of furfural to furoic acid. Among them, YALI0E15400p (FALDH2) has shown the highest conversion rate of furfural to furoic acid and resulted in two-fold increased cell growth and lipid production in the presence of 0.4 g/L of furfural. To our knowledge, this is the first report to identify the native furfural detoxification mechanism and increase furfural resistance through rational engineering in Y. lipolytica. Overall, these results will improve the potential of Y. lipolytica to produce lipids and other value-added chemicals from a carbon-neutral feedstock of lignocellulosic biomass. 相似文献
62.
Dawei Gong Huaguang Zhang Zhanshan Wang Bonan Huang 《Neural computing & applications》2013,22(2):205-210
This paper is concerned with the problem of global synchronization for a general complex networks. Based on a useful inequality and Kronecker product technique, a new criterion is obtained, which has fewer unknown variables and is a significant improvement in the performance. Synchronization criteria are derived by some new mathematical skills and Schur complement. The result is expressed by linear matrix inequalities, which can be easily computed and checked in practice. Finally, numerical examples will be used to show the effectiveness of the obtained result. 相似文献
63.
Wenyue Zhao Yanling Pei Danhua Zhang Yue Ma Shengkai Gong Huibin Xu 《Intermetallics》2011,19(3):429-432
The microstructure and tensile property changes of a γTiAl-based alloy, Ti-47Al-2Cr-2Nb-0.15B, during isothermal and cyclic high temperature exposures have been investigated. Microstructure coarsening, including the fracture, dissolution and spheroidization of α2 lamellae, is considered to be the main cause of the evident tensile property decreases of the alloy after isothermal and cyclic high temperature exposures. Dislocation emission near the broken lamellae is also an important phenomenon in the microstructure degradation during cyclic high temperature exposure, which originated from the thermal mismatch between α2 and γ phases. 相似文献
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分析了同步发电机交流励磁系统中存在的问题,提出应用斩波技术对其进行改造和优化.建立了改造后系统的数学模型,利用工程设计法设计出相应的调节器.依据发电机现场运行的机理,组建了双闭环自动控制系统,实验结果证明了该方案的可行性,为励磁改造和优化提供了一定的理论指导. 相似文献
66.
本文分析了现有数宇监控系统中的云台控制法,该方法基于派尔高协议通过串口间接控制云台:提出了基于智能监控系统的嵌入式IO直控云台结构,并结合S3C2440处理器设计了硬件结构、编写了嵌入式LinuX操作系统下的驱动程序。 相似文献
67.
对硅npn双极晶体管(C2060)室温下不同集电极偏置电流条件下γ辐照的总剂量效应进行了研究.结果表明,npn晶体管的辐照损伤程度随着辐照总剂量的增加而增加;尤其是实验中发现:在相同的辐照总剂量下随着辐照时集电极偏置电流的增加,晶体管的辐照损伤程度却在减轻.空间电荷模型的观点并不能很好地解释辐照损伤与辐照集电极偏置电流的关系.文章对空间电荷模型进行了修正,认为除氧化物俘获电荷和界面俘获电荷外,还会在外基区Si-SiO2界面附近形成电中性的电偶极子.利用修正后的理论可以很好地解释所有的实验结果. 相似文献
68.
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70.
Shu Gong Lim Wei Yap Yi Zhu Bowen Zhu Yan Wang Yunzhi Ling Yunmeng Zhao Tiance An Yuerui Lu Wenlong Cheng 《Advanced functional materials》2020,30(25)
An artificial basilar membrane (ABM) is an acoustic transducer that mimics the mechanical frequency selectivity of the real basilar membrane, which has the potential to revolutionize current cochlear implant technology. While such ABMs can be potentially realized using piezoelectric, triboelectric, and capacitive transduction methods, it remains notoriously difficult to achieve resistive ABM due to the poor frequency discrimination of resistive‐type materials. Here, a point crack technology on noncracking vertically aligned gold nanowire (V‐AuNW) films is reported, which allows for designing soft acoustic sensors with electric signals in good agreement with vibrometer output—a capability not achieved with corresponding bulk cracking system. The strategy can lead to soft microphones for music recognition comparable to the conventional microphone. Moreover, a soft resistive ABM is demonstrated by integrating eight nanowire‐based sensor strips on a soft trapezoid frame. The wearable ABM exhibits high‐frequency selectivity in the range of 319–1951 Hz and high sensitivity of 0.48–4.26 Pa?1. The simple yet efficient fabrication in conjunction with programmable crack design indicates the promise of the methodology for a wide range of applications in future wearable voice recognition devices, cochlea implants, and human–machine interfaces. 相似文献