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91.
Radisic V. Sawdai D. Scott D. Deal W.R. Linh Dang Li D. Chen J. Fung A. Samoska L. Gaier T. Lai R. 《Microwave Theory and Techniques》2007,55(11):2329-2335
In this paper, a sub-millimeter-wave HBT oscillator is reported. The oscillator uses a single-emitter 0.3 m15 m InP HBT device with maximum frequency of oscillation greater than 500 GHz. The passive components of the oscillator are realized in a two metal process with benzocyclobutene used as the primary transmission line dielectric. The oscillator is implemented in a common base topology due to its inherent instability. The design includes an on-chip resonator, output matching circuitry, and injection locking port. A free-running frequency of 311.6 GHz has been measured by down-converting the signal. Additionally, injection locking has been successfully demonstrated with up to 17.8 dB of injection-locking gain. This is the first fundamental HBT oscillator operating above 300 GHz. 相似文献
92.
Detergency of Vegetable Oils and Semi‐Solid Fats Using Microemulsion Mixtures of Anionic Extended Surfactants: The HLD Concept and Cold Water Applications
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Linh D. Do Chodchanok Attaphong John F. Scamehorn David A. Sabatini 《Journal of surfactants and detergents》2015,18(3):373-382
In spite of the increasing interest in cold temperature detergency of vegetable oils and fats, very limited research has been published on this topic. Extended surfactants have recently been shown to produce very promising detergency with vegetable oils at ambient temperature. However, the excessive salinity requirement (4–14 %) for these surfactants has limited their use in practical applications. In this work, we investigated the mixture of a linear C10–18PO–2EO–NaSO4 extended surfactant and a hydrophobic twin‐tailed sodium dioctyl sulfosuccinate surfactant for cold temperature detergency of vegetable oils and semi‐solid fats. Four vegetable oils of varying melting points (from ?10 to 28 °C) were studied, these were canola, jojoba, coconut and palm kernel oils. Anionic surfactant mixtures showed synergism in detergency performance compared to single surfactant systems. At temperatures above the melting point, greater than 90 % detergency was achieved at 0.5 % NaCl. While detergency performance decreased at temperatures below the melting point, it was still superior to that of a commercial detergent (up to 80 vs. 40 %). Further, results show that the experimental microemulsion phase behaviors correlated very well with predictions from the hydrophilic–lipophilic deviation concept. 相似文献
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Young Nam Yang Thi Thuy Linh Le Ji-Hye Hwang Ismayil S. Zulfugarov Eun-Ha Kim Hyun Uk Kim Jong-Seong Jeon Dong-Hee Lee Choon-Hwan Lee 《International journal of molecular sciences》2022,23(5)
The photosystem II PsbS protein of thylakoid membranes is responsible for regulating the energy-dependent, non-photochemical quenching of excess chlorophyll excited states as a short-term mechanism for protection against high light (HL) stress. However, the role of PsbS protein in long-term HL acclimation processes remains poorly understood. Here we investigate the role of PsbS protein during long-term HL acclimation processes in wild-type (WT) and npq4-1 mutants of Arabidopsis which lack the PsbS protein. During long-term HL illumination, photosystem II photochemical efficiency initially dropped, followed by a recovery of electron transport and photochemical quenching (qL) in WT, but not in npq4-1 mutants. In addition, we observed a reduction in light-harvesting antenna size during HL treatment that ceased after HL treatment in WT, but not in npq4-1 mutants. When plants were adapted to HL, more reactive oxygen species (ROS) were accumulated in npq4-1 mutants compared to WT. Gene expression studies indicated that npq4-1 mutants failed to express genes involved in plastoquinone biosynthesis. These results suggest that the PsbS protein regulates recovery processes such as electron transport and qL during long-term HL acclimation by maintaining plastoquinone biosynthetic gene expression and enhancing ROS homeostasis. 相似文献
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以橙汁为研究对象,选取市售100%橙汁及橙汁饮料各3种,采用CTAB法、SDS-CTAB法以及改良CTAB法提取其DNA,对所提取的DNA的浓度、纯度及扩增效率进行比较;同时选取橙UDP-葡糖基转移酶蛋白基因设计柑橘属植物特异性扩增引物,通过定性PCR检测其特异性和灵敏度,并应用于果汁中柑橘属植物的检测。实验结果证明,由改良CTAB法获得的DNA模板质量较高,适用于果汁中DNA的提取。UGT基因引物可对柑橘属植物产生特异性扩增,最低检测限为10pg/μL。将该引用物用于市售橙汁的检测,其检测结果为阳性,从而证明UGT基因特异性引物可用于果汁中的柑橘属植物成分的检测及鉴伪研究。 相似文献
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Quy Vu Khanh Nam Vi Hoai Linh Dao Manh Ban Nguyen Tien Han Nguyen Dinh 《Wireless Personal Communications》2022,122(3):2791-2815
Wireless Personal Communications - In recent years, the explosive growth of multimedia applications and services has required further improvements in mobile systems to meet transfer speed... 相似文献
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A dual criterion of equivalent linearization method is suggested. The mean-square responses of Duffing, Van der Pol and Lutes-Sarkani
oscillators subjected to random excitation are considered. The obtained results are compared with the numerical calculations
of original systems and approximate solutions obtained by three different methods including the conventional linearization
technique, energy method and regulation linearization method. The results show that in those nonlinear systems the accuracy
of the mean-square response is significantly improved by the proposed criterion. 相似文献