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Elucidation of the fragmentation pathways of a complex 3,7-O-glycosyl flavonol by CID, HCD, and PQD on an LTQ-Orbitrap Velos Pro hybrid mass spectrometer

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Chinese Journal of Natural Medicines 2015年第11期13卷 867-872页

作者： yang Wen-Zhi WU Wan-ying yang Min guo De-An Shanghai Research Center for Modernization of Traditional Chinese Medicine National Engineering Laboratory for TCM Standardization Technology Shanghai Institute of Materia Medica Chinese Academy of Sciences

The present study was designed to systematically investigate the ESI-MSn behavior of a complex 3, 7-O-glycosyl flavonol, kaempferol 3-O-α-L-[2,3-di-O-β-D-（6-E-p-coumaroyl）glucopyranosyl]-rhamnopyranosyl-7-O-α-L-rhamnopyranoside （KO） isolated from Epimedium wushanense, and to address the elimination priority among different glycosylation sites and different sugars/substituents. The direct-infusion ESI-MSn experiment of KO was performed on a hybrid LTQ-Orbitrap Velos Pro mass spectrometer in both negative and positive ion modes by three different fragmentation mechanisms （CID, HCD, and PQD）. The CID, HCD, and PQD analyses of KO exhibited remarkable discrimination in respect of the scan range, richness, and distribution of product ions through the entire spectra. KO experienced different fragmentation pathways between two ionization modes： the negative mode CID of KO eliminated the glycosyl portions （priority： 7-sugar 〉 3-substituent and terminal substituents 〉 inner sugar） and produced aglycone product ions at m/z 284.03/285.04; however, abundant sodium-adduct B32 together with subsequent ijX30 cleavages were found characteristic for the positive mode CID-MSn. The fragmentation pathways by CID for KO were proposed by analyzing the high accuracy ESI-MS＂ data. Complementary structural information of KO regarding the aglycone and glycosyl portions was obtained by analyzing the ESI-MSn data in both ionization modes. In conclusion, the LTQ-Orbitrap method facilitates highly reliable qualitative analysis of bioactive flavonoids with three alternative fragmentation modes.

关键词： Flavonol 3,7-O-glycoside LTQ-Orbitrap Fragmentation pathway

Prophenoloxidase from Pieris rapae:gene cloning,activity,and transcription in response to venom/calyx fluid from the endoparasitoid wasp Cotesia glomerata

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第2期12卷 103-115页

作者： Jia-ying ZHU Pu yang guo-xing WU Key Laboratory of Forest Disaster Warning and Control of Yunnan Province and Key Laboratory of Southwest Mountain Forest Resources Conservation and Utilization of Ministry of Education Southwest Forestry University Kunming 650224 China Research Institute of Resource Insects Chinese Academy of Forestry Kunming 650224 China College of Plant Protection Yunnan Agricultural University Kunming 650201 China

Prophenoloxidase (PPO) plays an important role in melanization, necessary for defense against intruding parasitoids. Parasitoids have evolved to inject maternal virulence factors into the host hemocoel to suppress hemolymph melanization for the successful development of their progeny. In this study, the full-length complementary DNA (cDNA) of a Pieris rapae PPO was cloned. Its cDNA contained a 2 076-base pair (bp) open reading frame (ORF) encoding 691 amino acids (aa). Two putative copper-binding sites, a proteolytic activation site, three conserved hemocyanin domains, and a thiol ester motif were found in the deduced amino acid sequence. According to both multiple alignment and phylogenetic analysis, P. rapae PPO gene cloned here is a member of the lepidopteran PPO-2 family. Injection of Cotesia glomerata venom or calyx fluid resulted in reduction of P. rapae hemolymph phenoloxidase activity, demonstrating the ability to inhibit the host's melanization. Real-time reverse transcriptase polymerase chain reaction (RT-PCR) showed that transcripts of P. rapae PPO-2 in the haemocytes from larvae had not significantly changed following venom injection, suggesting that the regulation of PPO messenger RNA (mRNA) expression by venom was not employed by C. glomerata to cause failure of melanization in parasitized host. While decreased P. rapae PPO-2 gene expression was observed in the haemocytes after calyx fluid injection, no detectable transcriptional change was induced by parasitization, indicating that transcriptional down-regulation of PPO by calyx fluid might play a minor role involved in inhibiting the host's melanization.

关键词： Prophenoloxidase Cloning Venom Calyx fluid Gene expression Parasitoid

Enhanced photocataly tic activity of TiO_2 by surface fluorination in degradation of organic cationic compound

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Journal of Environmental Sciences 2007年第1期19卷 86-89页

作者： yang Shi-ying CHEN You-yuan ZHENG Jian-guo CUI ying-jie Key Lab of Maline Environmental Science and Ecology Ministry of Education Ocean University of China Qingdao 266100 China College of Environmental Science and Engineering Ocean University of China Qingdao 266100 China

Experiments were carried out to investigate the influence of TiO2 surface fluorination on the photodegradation of a representative organic cationic compound, Methylene Blue （MB）. The eleetropositive MB shows poor adsorption on TiO2 surface; its degradation performs a HO. radical-mediated mechanism. In the F-modified system, the kinetic reaction rate enlarged more than 2.5 fold that was attributed mainly to the accumulating adsorption of MB and the increased photogenerated hole available on the F-modified TiO2 surface.

关键词： photocatalysis mechanism adsorption surface fluorination photogenerated hole Methylene Blue(MB)

Primary Mg_(2)Si phase and Mg_(2)Si/α-Mg interface modified by Sn and Sb elements in a Mg-5Sn-2Si-1.5Al-1Zn-0.8Sb alloy

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Journal of Magnesium and Alloys 2022年第11期10卷 3234-3249页

作者： Wenpeng yang ying Wang Hongbao Cui Guangxin Fan Xuefeng guo School of Materials Science and Engineering Henan Polytechnic UniversityJiaozuoHenan 454000PR China Henan International Joint Research Laboratory for High-Performance Light Metallic Materials and Numerical Simulations Henan Polytechnic UniversityJiaozuoHenan 454000PR China

The microstructure of primary Mg_(2)Si and the interface of Mg_(2)Si/α-Mg modified by Sn and Sb elements in an as-cast Mg-5Sn-2Si-1.5Al-1Zn-0.8Sb(wt.%) alloy were *** the primary Mg_(2)Si phase not only the Si atoms but also the Mg atoms could be substituted by Sn and Sb atoms,resulting in the slightly reduced lattice constant a of 0.627 *** OR of Mg_(2)Si phase and α-Mg in the form of[001]Mg_(2)Si‖[01■1]α,(220)Mg_(2)Si‖(0■12)αwas *** primary Mg_(2)Si phase and α-Mg matrix two transitional nano-particle layers were *** the rim region of primary Mg_(2)Si particle,Mg_(2)Sn precipitates sizing from 5 nm to 50 nm were *** to the boundary of primary Mg_(2)Si particle,luxuriant columnar crystals of primary Mg_(2)Sn phase with width of about 25 nm and length of about100 nm were distributed on the α-Mg *** lattice constant of the Mg_(2)Sn precipitate in primary Mg_(2)Si particle was about 0.756 *** ORs between Mg_(2)Sn and Mg_(2)Si were found,in which the Mg_(2)Sn precipitates had strong bonding interfaces with Mg_(2)Si *** new minor ORs between Mg_(2)Sn phase and α-Mg were *** lattice constant of primary Mg_(2)Sn phase was enlarged to 0.813 nm owing to the solution of Sn and Sb *** Mg_(2)Sn had edge-to-edge interfaces with α-***,the primary Mg_(2)Si particle and α-Mg were united and the interfacial adhesion was improved by the two nano-particles layers of Mg_(2)Sn phase.

关键词： Mg_(2)Si Mg_(2)Sn Modification Interface HRTEM

Hotspots of Photocatalytic Materials in 2020 Based on Big Data

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Chinese Journal of Structural Chemistry 2021年第10期40卷 1317-1327页

作者： CHEN Bao-guo ying Qiu-yang SHEN Jin-Ni Institute of Science and Technology and Social Research Fuzhou UniversityFuzhou 350100China International College Krirk UniversityBangkok 10220Thailand State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China School of Chemistry Fuzhou UniversityFuzhou 350100China

Based on Cite Space software,big data bibliometrics analysis was carried out on the keywords of papers of photocatalytic materials published in *** the hotspots and directions can help young scholars to understand the latest *** the Web of Sciences,4147 related papers were searched with"photocatalytic materials"as the main *** analysis showed that the hotspots were g-C_(3)N_(4),Mxene and metal-organic frameworks (MOF) and titanium dioxide (TiO_(2)).

关键词： Cite Space visual analysis photocatalytic materials big data analysis

同方期刊数据库

Vortex analysis of water flow through gates by different vortex identification methods

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Journal of Hydrodynamics 2023年第1期35卷 112-124页

作者： Chun-ying Shen Rui-guo yang Shan Qing Shi-hua He Faculty of Electrical Power Engineering Kunming University of Science and TechnologyKunming650500China

The pre-gate suction vortex,gate-bottom-edge transverse vortex,gate-slot vertical vortex,and downstream-of-gate return vortex are important factors affecting the flow instability of flat gates,which may lead to fatigue failure in severe *** study used the volume of fluid(VOF)model and large eddy simulation(LES)method to accurately capture the transient turbulence characteristics of flow under different water flow conditions and reveal the flow field and vortex *** Q—criterion,Omega(Ω)method,and latest third-generation Liutex vortex identification method were used to analyze and compare the pre-gate suction vortex,gate-slot vertical vortex,and downstream-of-gate return vortex,focusing on the ability of each vortex identification method to capture the flow field information and vortex *** results reveal that theΩmethod and Liutex method are less dependent on the threshold value,and the Liutex method captures a wide range of pre-gate *** flow conditions cause changes in the vortex structure of over-gate *** the relative opening of the gate is smaller,the intensity of the vortices in the flow field around the gate is greater,the return vortices downstream of the gate are more disordered,and the vortex changes are more violent,which in turn affects the efficient and stable operation of the gate.

关键词： Vortex features vortex identification methods Liutex Ωmethod Q-criterion large eddy simulation(LES)

Robust cubature Kalman filter method for the nonlinear alignment of SINS

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Defence Technology（防务技术） 2021年第2期17卷 593-598页

作者： Shi-luo guo ying-jie Sun Li-min Chang yang Li Department of Instrument Electric Aviation University Air ForceChangchunPeople’s Republic of China

Nonlinear initial alignment is a significant research topic for strapdown inertial navigation system(SINS).Cubature Kalman filter(CKF)is a popular tool for nonlinear initial *** CKF assumes that the statics of the observation noise are pre-given before the filtering ***,any unpredicted outliers in observation noise will decrease the stability of the *** view of this problem,improved CKF method with robustness is *** fading factors are introduced to rescale the observation noise *** the update stage of the filter can be autonomously tuned,and if there are outliers exist in the observations,the update should be less *** the Gaussian assumption of KF,the Mahalanobis distance of the innovation vector is supposed to be Chi-square *** a judging index based on Chi-square test is designed to detect the noise outliers,determining whether the fading tune are *** proposed method is applied in the nonlinear alignment of SINS,and vehicle experiment proves the effective of the proposed method.

关键词： SINS Nonlinear alignment Cubature Kalman filter Robust Multiple fading factors Hypothesis test

Role of the reduction site in the fluorinated or sulfated TiO_2 photocatalytic process

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Journal of Environmental Sciences 2007年第10期19卷 1239-1244页

作者： yang Shi-ying HU Hong CHEN You-yuan ZHENG Jian-guo CUI ying-jie Key Lab of Marine Environmental Science and Ecology Ministry of Education Ocean University of China Qingdao 266100 China College of Environmental Science and Engineering Ocean University of China Qingdao 266100 China

In this article, the effects of ZiO2 surface fluorination and sulfation, on the active oxygen species formed at the reduction site in the photocatalytic process, namely O2^＊- and H2O2, were investigated from a new perspective. The superoxide radical, （O2^＊-）, was determined by colorimetry of nitroblue tetrazolium, a prominent O2^＊- scavenger. Hydrogen peroxide （H2O2） was estimated by using the iodide-starch method. In the naked TiO2 photocatalysis, O2^＊-, though less reactive, was a very important intermediate. When the TiO2 surface was fluorinated, more O2^＊- and H2O2 were produced, which indicated that the surface modification could greatly reduce the recombination of photogenerated electrons and holes, thus enhancing the photocatalytic rate. In the sulfated system, photocatalysis proceeded with a more complicated mechanism. These results added support to the view of fluoride-induced enhancement and sulfide＇s nonappreciable inhibition effect.

关键词： TiO2 photocatalysis superoxide radicals surface modification initial mechanism

联合多源卫星测高数据获取青藏高原湖泊水位变化

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大地测量与地球动力学 2025年第1期45卷 22-28,35页

作者：宋昊天文汉江郭英刘焕玲杨熙骆新伟中核勘察设计研究有限公司郑州市450003 中国测绘科学研究院北京市100036 北京房山人卫激光国家野外科学观测研究站北京市100036 测绘科学与地球空间信息技术自然资源部重点实验室北京市100036 山东科技大学测绘与空间信息学院青岛市266590 自然资源部第二大地测量队哈尔滨市150086

利用ICESat、Cryosat-2、ICESat-2三颗测高卫星数据提取2003-2022年青藏高原湖泊水位变化序列,并以青海湖为例对比分析Cryosat-2 LRM三种重跟踪算法(Ocean-CFI、UCL Land-ice、OCOG),结果表明,OCOG算法最优。利用青海湖、纳木错、美玛... 详细信息

利用ICESat、Cryosat-2、ICESat-2三颗测高卫星数据提取2003-2022年青藏高原湖泊水位变化序列,并以青海湖为例对比分析Cryosat-2 LRM三种重跟踪算法(Ocean-CFI、UCL Land-ice、OCOG),结果表明,OCOG算法最优。利用青海湖、纳木错、美玛错、鲁玛江冬错的水文站数据,对通过卫星测高数据提取的湖泊水位变化时间序列精度进行评价,结果发现,本文提取的湖泊水位变化值精度较高,青海湖水位变化时间序列与下社站实测结果差异的均方根仅为0.092 m,纳木错湖水位变化时间序列与实测结果的相关系数达0.989。相同时段内不同测量技术的精度分析表明,Cryosat-2 SARIn测量模式的精度略高于ICESat-2。提取青藏高原106个湖泊2003-2022年水位序列,并分析其变化趋势,结果表明,106个湖泊中19个湖泊水位呈下降趋势,83个湖泊水位呈上升趋势。

关键词：多源遥感数据卫星测高青藏高原湖泊水位变化