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Enhanced quality of Al_(2)O_(3)/SiC gate stack via microwave plasma annealing

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Rare Metals 2024年第10期43卷 5362-5371页

作者： Nan-Nan You Xin-yu Liu Qian Zhang Zhen Wang Jia-Yi Wang Yang Xu Xiu-Yan Li yu-zheng guo Sheng-Kai Wang High-Frequency High-Voltage Device and Integrated Circuits R&D Center Institute of Microelectronics of the Chinese Academy of SciencesBeijing 100029China School of Integrated Circuits University of Chinese Academy of SciencesBeijing 100049China School of Electrical Engineering and Automation Wuhan UniversityWuhan430072China Department of Micro/Nano Electronics School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The high-quality gate dielectric on silicon carbide(SiC)surface is critical to fabricate high-performance SiC metal-oxide-semiconductor field-effect transistors(MOSFETs).This research employs microwave plasma annealing(MPA)to obtain high-quality Al_(2)O_(3)/SiC gate *** designing MPA atmosphere and optimizing the plasma power,the SiC MOS capacitor with a Al_(2)O_(3)dielectric film shows the enhanced *** interface state density is reduced by 1 order of magnitude to 6×10^(11)cm^(-2)·eV^(-1),the breakdown electric field is increased,and the voltage shift is effectively suppressed Besides,the mechanism of MPA process is discussed in terms of the thermal effect and reactant species.X-ray photoelectron spectroscopy(XPS)results unveil oxygen plasma plays the main *** plasma power during the MPA process results in defect repairs of the firstneighbor Al-O bonding and partial removal of Al-O-H bond from the interface *** study demonstrates that MPA process is an effective option to realize highquality dielectric and interface on SiC.

关键词： Silicon carbide Al_(2)O_(3) Metal-oxide-semiconductor Microwave plasma annealing Defect repairs X-ray photoelectron spectroscopy

Synthesis of novel biscalixarene-tube containing two kinds of calix[4]arene derivative units

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Chinese Chemical Letters 2008年第1期19卷 9-11页

作者： Fa Fu Yang Li M ing Liu Chao Hui Liu Xi-ao Hua zheng yu guo College of Chemistry and Materials Fujian Normal University Fuzhou 350007 China

A novel biscalixarene with two kinds of calix[4]arene derivative units connected by four bridging chains, was facilely＇ synthesized by ＂1 ＋ 1＂ condensation mode in high yield. The element analyses, ESI-MS, ^1H NMR and ^1H-^1H COSY spectrum showed that the calix[4]arene units of compound 4 were in cone conformations and compound 4 possessed biscalixarene-tube structure. 2007 Fa Fu Yang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Biscalixarene Tube Synthesis ^1H-^1H COSY

A new pteridinedione from Whitmania pigra

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Chinese Chemical Letters 2010年第5期21卷 603-605页

作者： yun Feng zheng,Cun yu Li,guo Ping Peng,Hong Yang Li College of Pharmacy,Nanjing University of Chinese Medicine,Nanjing 210046,China [a] College of Pharmacy Nanjing University of Chinese Medicine Nanjing 210046 China

A new compound,6-methylsulfinylthieno[3,2-g]-2,4(1H,3H)-pteridinedione,was isolated from the water extract of Whitmania pigra *** structure was elucidated on the basis of NMR and ESIMS spectra.

关键词： Whitmania pigra Heterocycle 6-Methylsulfinylthieno[3,2-g]-2,4(1H,3H)-pteridinedione

Higher Order Moment Spectra Time-Frequency Analysis of the Geophysical Signal

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Wuhan University Journal of Natural Sciences 2001年第4期6卷 801-806页

作者： Liu Xiang hong, Zhao zheng yu , Xie Shu guo, Ni Bin\|bin School of Electronic Information, Wuhan University, Wuhan 430072, China Wuhan University School of Electronic Information Wuhan China (GRID:grid.49470.3e) (ISNI:***)

On the basis of an introduction of the Wigner Higher-Order spectra (WHOS) and a general class of time-frequency higher-order moment spectra, the geophysical signal was analyzed using the higher order time-frequency distributions (TFD). Simulation results obtained in this paper show that the higher-order TFD (Wigner Bispectrum, Wigner Trispectrum and Choi-Williams Trispectrum) have much better Time-Frequency Concentration than the second-order TFD, and the reduced interference higher-order TFD such as CWT can effectively reduce the cross-term in multicomponent signals and simultaneously obtain high time-frequency concentration.

关键词： non stationary Wigner high order spectra time frequency higher order moment spectra cross term attenuation

Submerged culture of chromium-enriched Termitomyces albuminosus

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菌物学报 2008年第1期27卷 118-125页

作者： HUZhong-Ce zheng Xiao-Dong CHEN Xin-Ai zheng yu-guo College of Biosystem Engineering and Food Science Zhejiang University Hangzhou 310029 China Institute of Bioengineering Zhejiang University of Technology Hangzhou 310032 China

A species of mushroom, Termitomyces albuminosus, was cultured in liquid medium for production of chromium-enriched mycelium. The influence of chromium (Ⅲ ) on mycelial growth of T. albuminosus was investigated. An optimum medium composed of 5.6g/L yeast extract, 51.6g/L hydrolyzed rice, 2g/L KH2PO4, and 20mg/L chromium(Ⅲ ) with initial pH of 4.5 was obtained by using method of central composite design (CCD). After incubation of 84h, the maximal biomass of chromium-enriched mycelia reached 24.23g DMW(dried mycelial weight)/L with 272μg/g DMW chromium content in 500mL flasks containing 100mL medium with an inoculum of 8% on a shaker of 100r/min under an optimized cultivation condition at 28℃.

关键词：富铬蚁巢伞鸡菌液体培养培养基

Two Methods to Solve the Ionospheric Electron Concentration Horizontal Gradient at Chongqing

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Wuhan University Journal of Natural Sciences 2000年第3期5卷 320-322页

作者： Chong Yan-wen, Huang Tian-xi, Zhao zheng-yu, Xie Shu-guo, Yao Yong-gang College of Electronic Information, Wuhan University, Wuhan 430072, China Wuhan University College of Electronic Information Wuhan China (GRID:grid.49470.3e) (ISNI:***)

The electron concentration horizontal gradient vector of the ionosphere and its south-north and east-west components over Chongqing station are analyzed and calculated, using the first approximation, time correlation and space correlation and another approach introduced. And then, the validity of the two methods is analyzed and compared.

关键词： horizontal gradient of ionospheric electron concentration horizontal gradient vector space correlation time correlation

2,2-二甲基环丙腈水合酶产生菌的氮离子注入选育及突变株产酶条件研究

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高校化学工程学报 2007年第6期21卷 971-976页

作者：吴玉峰郑裕国沈寅初浙江工业大学生物工程研究所杭州310032

离子注入技术被广泛应用于微生物的品种改良。利用N+离子注入法对本实验室筛选并保藏的产2,2-二甲基环丙腈水合酶菌种Pseudomonas ***0509进行选育,以提高2,2-二甲基环丙甲酰胺的产量,为进一步的手性拆分提供更多的原料。结果表明,氮离... 详细信息

离子注入技术被广泛应用于微生物的品种改良。利用N+离子注入法对本实验室筛选并保藏的产2,2-二甲基环丙腈水合酶菌种Pseudomonas ***0509进行选育,以提高2,2-二甲基环丙甲酰胺的产量,为进一步的手性拆分提供更多的原料。结果表明,氮离子注入诱变Pseudomonas ***0509的存活率曲线符合离子注入诱变的"马鞍型"特征曲线。通过离子注入获得的突变株的腈水合酶活性有显著提高,其中突变株F60-4的酶活达30.1 U·mL-1,约为原始菌株的9倍。对突变株F60-4进行产酶条件的优化考察,获得了培养条件。F60-4菌株产酶的最佳碳源是葡萄糖(2g·L-1),最佳氮源是酵母粉(10g·L-1),最适初始pH值为6.5,最适发酵温度为20℃,最佳诱导剂为1.0g·L-1的己内酰胺。与原始菌株Pseudomonas ***0509相比,突变株F60-4对有机氮源的利用率更高。最佳诱导剂由己内酰胺代替了原来的2,2-二甲基环丙甲腈,使实验操作简便。突变株F60-4的发酵周期为36h,比原始菌株缩短了12h。

关键词：氮离子注入腈水合酶 2,2-二甲基环丙甲腈 2.2-二甲基环丙甲酰胺

阳离子交换树脂SAC 001×7对阿卡波糖的吸附性能研究

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高校化学工程学报 2012年第3期26卷 493-498页

作者：王亚军董方智于蕾郑裕国浙江工业大学生物工程研究所浙江杭州310014

研究了水相中阳离子交换树脂SAC001×7对阿卡波糖的吸附平衡、吸附热力学及吸附动力学,探讨了运用SAC001×7从发酵液中分离阿卡波糖的可行性。吸附平衡实验表明,SAC001×7吸附阿卡波糖的最大平衡吸附容量在研究范围内随温度升高而增大,... 详细信息

研究了水相中阳离子交换树脂SAC001×7对阿卡波糖的吸附平衡、吸附热力学及吸附动力学,探讨了运用SAC001×7从发酵液中分离阿卡波糖的可行性。吸附平衡实验表明,SAC001×7吸附阿卡波糖的最大平衡吸附容量在研究范围内随温度升高而增大,在313 K时达到951.5 mg g 1,且吸附等温线符合Langmuir模型。计算了阿卡波糖吸附热力学函数,ΔG0,ΔH>0,表明SAC001×7吸附阿卡波糖是一个吸热过程,升高温度促进吸附。吸附动力学实验表明,90%以上的阿卡波糖吸附发生在前40 min以内,120 min达到吸附平衡,阿卡波糖交换速率受颗粒内扩散限制。在考察浓度范围内,内扩散速率常数随阿卡波糖初始浓度增大而增大,受温度的影响较小。

关键词：阿卡波糖吸附热力学动力学

非均相磺化反应体系制备(1→3)-β-D-葡聚糖硫酸酯

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化学工程 2006年第4期34卷 47-50页

作者：王亚军姚善泾郑裕国浙江工业大学生物工程研究所浙江杭州310014 浙江工业大学绿色化学合成技术国家重点实验室培育基地浙江杭州310032 浙江大学化学工程与生物工程学系

考察硫酸和正丙醇组成的非均相磺化反应体系制备(1→3)β--D-葡聚糖硫酸酯的可行性,利用元素分析、红外光谱、1H NMR、扫描电镜等技术对产物进行结构表征。结果表明,制备得到的(1→3β)--D-葡聚糖硫酸酯完全溶于水,质量收率约37.4%,经... 详细信息

考察硫酸和正丙醇组成的非均相磺化反应体系制备(1→3)β--D-葡聚糖硫酸酯的可行性,利用元素分析、红外光谱、1H NMR、扫描电镜等技术对产物进行结构表征。结果表明,制备得到的(1→3β)--D-葡聚糖硫酸酯完全溶于水,质量收率约37.4%,经验式为(C6H10O5)25.9SO3.7H2O,红外谱图在1 240 cm-1、810 cm-1存在特征吸收带,1H NMR分析也支持产物为(1→3)-β-D-葡聚糖硫酸酯。

关键词： (1→3)-β-D-葡聚糖硫酸酯非均相反应磺化硫酸正丙醇