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China Ocean Engineering 2022年第1期36卷 28-37页

作者： HUANG Shu-ting liu yan-jun XUE Gang XUE Yi-fan Institute of Marine Science and Technology Shandong UniversityQingdao 266237China School of Mechanical Engineering Shandong UniversityJinan 250061China

In coastal sea areas with the bimodal Ochi-Hubble wave spectrum, such as parts of the China Sea and Indian Ocean,wave energy is the superposition of wind wave and swell. Traditional heaving buoy wave energy converters developed with narrowband wave spectrums suffer from big energy loss in these areas, leading to lower power absorption efficiency and higher generating costs. In contrast, multi-freedom buoy has different resonant frequencies and maximal power capture wave frequencies in different degrees of freedom(DOFs). Therefore, this study proposed using two DOFs to capture the energy of wind wave and swell correspondingly. A heave and pitch buoy model was established by potential flow theory and validated by experimental data. Coupling effect on the motion and power absorption, power capture frequency distribution and power absorption with different linear power takeoff system damping coefficients were analyzed to reveal the hydrodynamic response and the power performance of the two DOFs. The results indicate that by using heave and pitch DOFs, the wave energy components of wind wave and swell were captured in a targeted manner. It demonstrates that the 2-DOF buoy is an effective tool to avoid the energy loss and realize the efficient power absorption in coastal sea areas with bimodal Ochi-Hubble waves.

关键词： wave energy power performance oscillating buoy multi degrees of freedom Ochi−Hubble spectrum

Experimental observations of ferroelectricity in double pyrochlore Dy2Ru2O7

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Frontiers of physics 2014年第1期9卷 82-89页

作者： Zai-Chun Xu Mei-Feng liu Lin Lin Huimei liu Zhi-Bo yan jun-Ming liu Laboratory of Solid State Microstructures Nanjing University Nanjing 210093 China

Double pyrochlore Dy2Ru207 is synthesized and its magnetism and ferroelectricity below the Ru4＋ spin ordering temperature （NI00 K） are investigated. The ferroelectric transition appears at -18 K, much higher than the Dy3＋ spin ordering point at -1.8 K and lower than the Ru4＋ spin ordering point at -100 K. The measured electric polarization at ,-2 K is as big as 145℃/m2 in the polycrystalline samples. It is argued that the ferroelectricity is possibly ascribed to the electric dipole ordering arising from the collective monopole excitations in the Dy3＋ tetrahedrons in prior to the Dy3＋ spin ordering into spin-ice like state below -1.8 K.

关键词： pyrochlore oxides multiferroics magnetically induced ferroelectricity

Cloning, expression and chitin-binding activity of two peritrophin-like protein genes in the common cutworm, Spodoptera fitura

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Insect Science 2014年第4期21卷 449-458页

作者： Wei-jun Chen Li-Xia Huang Dan Hu Li-yan liu jun Gu Li-Hua Huang Qi-Li Feng Guangdong Provincial Key Laboratory of Biotechnology for Plant Development School of Life Sciences South China Normal UniversityGuangzhou China

Insect midgut secretes a semi-permeable peritrophic membrane （PM）, which plays important roles in protecting the midgut and helping with food digestion. The lep- idopteran larvae produce type 1 PM, which is degraded when insects develop into the metamorphic stages. However, the underlying mechanism is unclear. In the present study, two peritrophin-like proteins （peritrophin-57 and 37） were identified from the midgut expression sequence tag library and transcriptome of the common cutworm, Spodoptera litura. The temporal and spatial expression patterns and responses to the induction of 20- hydroxyecdysone （20E） and starvation were examined by real-time quantitative polymerase chain reaction according to their common sequence region. The chitin-binding activity was also studied using a competitor, calcofluor. The open reading frames are 1 554 and 1 020 bp, respectively. They shared four highly conserved peritrophin-A domains and were ex- pressed only in the midgut rather than in the other tissues, including fat body, epidermis, Malpighian tube and hemolymph. Their transcriptional expression could only be detected at the larval stages rather than in eggs, prepupae, pupae and adults. The purified protein of peritrophin-37 bound to chitin in a dose-dependent manner. These results indicate that the two proteins are peritrophins, the structural components of PM. In addition, the messenger RNA levels of the two peritrophins were significantly down-regulated by 20E injection, whereas feeding/starvation had no effect on the expression. These findings suggest that the increase of20E titer may be an important factor which controls the degradation of PM during metamorphosis.

关键词： metamorphosis peritrophic membrane peritrophin starvation 20-hydroxyecdysone

CuO Nanoparticle Modified ZnO Nanorods with Improved Photocatalytic Activity

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Chinese Physics Letters 2013年第4期30卷 145-149页

作者： WEI Ang XIONG Li SUN Li liu yan-jun LI Wei-Wei Key Laboratory for Organic Electronics&Information Displays(KLOEID Nanjing University of Posts and TelecommunicationsNanjing 210046

Cupric oxide(CuO)nanoparticles were grown on zinc oxide(ZnO)nanorod(NR)arrays to form ZnO–CuO corn-like composites via a simple two step solution-based ***,ZnO nanorods were grown on a glass substrate by the hydrothermal ***,CuO crystals were photochemically deposited on ZnO NRs using ultraviolet(UV)light irradiation at room *** density and size of CuO nanoparticles(NPs)on ZnO NRs can be controlled by the irradiation time of UV *** structural and optical properties of ZnO–CuO nanocomposites were characterized by using various techniques such as UV-vis absorption spectroscopy,photoluminescence,scanning electron microscopy,energy dispersive x-ray spectroscopy,and x-ray ***–CuO nanocomposites show an excellent improvement in photocatalytic characteristics compared to bare ZnO NRs.

关键词： composites nanoparticles particle

Improvement on Mixograph test through water addition and parameter conversions

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Journal of Integrative Agriculture 2015年第9期14卷 1715-1722页

作者： SUN Jia-zhu yanG Wen-long liu Dong-cheng ZHAO jun-tao LUO Guang-bin LI Xin liu yan-jun GU O Jin-kao ZHANG Ai-min State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyChinese Academy of Sciences Zhaoxian Institute of Agricultural Sciences Shijiazhuang Academy of Agriculture and Forestry Sciences

To improve Mixograph testing effect, Farinograph measurements were adopted as a quality standard and changes in water absorption and parameter conversion in Mixograph test were explored. Comparative study showed that increasing water absorption to about 73% and converting original parameters to compound parameters in Mixograph tests signiifcantly increased their predictive power for lfour quality. These efforts also enabled the adoption of ifxed water addition level in Mixograph test and simpliifed the test procedure signiifcantly. With the success in parameter conversions, Mixograph test results were successful y described by Farinograph parameters, which al ow breeders to compare and exchange test results easily. Al these changes optimized the ofifcial method of Mixograph test with simpliifed procedure and enhanced reliability and made the Mixograph being the superior tool for quality assessment in wheat-breeding programs.

关键词： Mixograph water absorption compound parameter constant water addition parameter conversion

Extraction and Characterization of Antioxidant Compositions From Fermented Fruit Juice of Morinda citrifolia (Noni)

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Agricultural Sciences in China 2007年第12期6卷 1494-1501页

作者： liu Chang-hong XUE Ya-rong YE Yong-hang YUAN Feng-feng liu jun-yan SHUANG Jing-lei Laboratory of Molecular ＆ Applied Microbiology State Key Laboratory of Pharmaceutical Biotechnology Nanjing University Nanjing 210093 P.R.China School of Plant Protection Nanjing Agricultural University Nanjing 210095 P.R.China

Extraction and characterization of antioxidative compositions from the extracts of fermented Xisha Noni （Morinda citrifolia L.） juice were studied. The antioxidative constituents of 184.6 g freeze-dried extracts of naturally fermented Xisha Noni juice were isolated successfully by petroleum ether, EtOAc and n-BuOH solvents, and the antioxidative effects were measured according to scavenging activity against hydroxyl generated in Fenton reaction system and superoxide anion radicals in pyrogallol autoxidation system. The EtOAc extract exhibited most significantly higher （P 〈 0.01） antioxidative activity than mannitol or vitamin C, while the petroleum ether and n-BuOH extracts showed lower activities compared to mannitol. Three antioxidant phenolic compounds, isoscopoletin, aesculetin and 3,3＇,4＇,5,7-pentahydroxyflavone （quercetin） were isolated from the EtOAc extract by several chromatography techniques for the first time. The results suggest that several compounds, in particular, the phenolic compounds, contribute separately or synergistically to the antioxidative activity of fermented Noni fruit juice.

关键词： antioxidant activity Morinda citrifolia L. fermented fruit juice

Preparation of tricalcium silicate and investigation of hydrated cement

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Journal of Central South University 2020年第11期27卷 3227-3238页

作者： TAN yan-ni CHEN Wen-juan liu Yong liu yan-jun State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Tricalcium silicate cement(TSC)has been widely used in dental materials because of its self-setting behavior,good bioactivity,biocompatibility,osteoinductivity,and antibacterial *** silicate(C3S)powder was prepared by Pechini technique with a calcining temperature of 1300℃ for 3 *** influence of liquid/powder(L/P)rate on the setting time and the mechanical property of TSC was *** methods including XRD,FTIR,SEM-EDS,TEM,and ICP-AES were utilized to study the properties of C3S powder and its hydrated *** bioactivity and biocompatibility of the cement were investigated by soaking test and cell culture,*** results show that the L/P rate plays an important role in the setting time and the compressive strength of *** surface of TSC was covered by hydroxyapatite deposition during the immersion experiment and the cells attachment on the surface of TSC was well,which indicated that TSC has good bioactivity and *** addition,TSC has excellent antibacterial properties against Staphylococcus *** conclusion,TSC is a promising candidate for root canal filling materials.

关键词： tricalcium silicate powder chemical synthesis inorganic compounds microstructure

考虑空间协同效应的排桩斜撑支护体系分段拆撑法研究

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岩土力学 2010年第9期31卷 2854-2860页

作者：刘俊岩刘燕王海平济南大学土木建筑学院济南250022 济南市市政工程设计研究院有限责任公司济南250002

与水平内支撑比较,排桩斜撑支护体系用于深大基坑开挖时具有诸多优越性。但关于斜撑拆除的研究相对滞后,使该支撑形式的利用受到一定的限制。内支撑的拆除多采用"先撑后拆"方案,文中从排桩斜撑支护体系的协同变形理论出发,提出了分区分... 详细信息

与水平内支撑比较,排桩斜撑支护体系用于深大基坑开挖时具有诸多优越性。但关于斜撑拆除的研究相对滞后,使该支撑形式的利用受到一定的限制。内支撑的拆除多采用"先撑后拆"方案,文中从排桩斜撑支护体系的协同变形理论出发,提出了分区分段"先拆后撑"的思路;利用最小势能解,推导了该类支护体系在分段拆撑过程中,拆撑区段长度的计算方法;并结合具体工程实例,对该计算理论和结果加以验证。通过研究,冠梁弯矩、排桩弯矩和位移是决定分段长度的主要因素,并提出了该类支护体系的全过程优化设计的概念,可为今后该类支护体系的拆撑设计和施工提供依据和借鉴。

关键词：基坑斜撑换撑空间协同效应

Dalestones A and B, two anti-inflammatory cyclopentenones from Daldinia eschscholzii with an edited strong promoter for the global regulator LaeA-like gene

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Chinese Journal of Natural Medicines 2019年第5期17卷 387-393页

作者： ZHOU Zhen-Zhen ZHU Hong-Jie yanG Cheng-Long liu yan-jun JIANG Nan XIAO Yong-Sheng SHI Li-Yun JIAO Rui-Hua GE Hui-Ming TAN Ren-Xiang State Key Laboratory of Pharmaceutical Biotechnology Institute of Functional Biomolecules Nanjing University State Key Laboratory Cultivation Base for TCM Quality and Efficacy Nanjing University of Chinese Medicine School of Pharmacy Nanjing Medical University

Replacement of the native promoter of the global regulator Lae A-like gene of Daldinia eschscholzii by a strong gpdA promoter led to the generation of two novel cyclopentenone metabolites, named dalestones A and B, whose structures were assigned by a combination of spectroscopic analysis, modified Mosher's reaction, and electronic circular dichroism(ECD). Dalestones A and B inhibit the gene expression of TNF-α and IL-6 in LPS-induced RAW264.7 macrophages.

关键词： Daldinia eschscholzii Global regulator Cyclopentenone

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多变量系统的耦合梯度辨识算法与性能分析

控制与决策 2016年第8期31卷 1487-1492页

作者：刘艳君丁锋江南大学轻工过程先进控制教育部重点实验室江苏无锡214122 江南大学物联网工程学院江苏无锡214122

针对多变量系统维数大、参数多、一般的辨识算法计算量大的问题,基于耦合辨识概念,推导多变量系统的耦合随机梯度算法,利用鞅收敛定理分析算法的收敛性能.算法的主要思想是将系统模型分解为多个单输出子系统,在子系统的递推辨识过程中,... 详细信息

针对多变量系统维数大、参数多、一般的辨识算法计算量大的问题,基于耦合辨识概念,推导多变量系统的耦合随机梯度算法,利用鞅收敛定理分析算法的收敛性能.算法的主要思想是将系统模型分解为多个单输出子系统,在子系统的递推辨识过程中,将每个子系统的参数估计值耦合起来.所提出算法与最小二乘算法和耦合最小二乘算法相比,具有较少的计算量,收敛速度可以通过引入遗忘因子得到改善.性能分析表明了所提出算法收敛,仿真实例验证了算法的有效性.

关键词：多变量系统参数估计随机梯度性能分析耦合辨识概念