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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

Investigation and Discussion on the Beach Morphodynamic Response Under Storm Events Based on A Three-Dimensional Numerical Model

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China Ocean Engineering 2021年第1期35卷 12-25页

作者： XIE Ming-xiao LI Shan ZHANG Chi yang zhi-wen HOU zhi-qiang ZHANG Huaqing Key Laboratory of Engineering Sediment Tianjin Research Institute for Water Transport EngineeringM.O.T.Tianjin 300456China CCCC First Harbor Engineering Co.Ltd. Tianjin 300461China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China

A well-established 3D phase-averaged beach morphodynamic model was applied to investigate the morphodynamics of a typical artificial beach,and a series of discussions were made on the surfzone hydro-sedimentological processes under calm and storm *** results revealed that the nearshore wave-induced current presents a significant 3D structure under stormy waves,where the undertow and longshore currents exist simultaneously,forming a spirallike circulation system in the *** longshore sediment transport would shorten the sediment supply in the cross-shore direction,subsequently suppress the formation of sandbars,showing that a typical recovery profile under calm waves does not necessarily develop,but with a competing process of onshore drift,undertow and longshore *** transport rate during storms reaches several hundreds of times as those under calm waves,and two storm events contribute approximately 60%to the beach *** transport pattern under calm waves is mainly bed load,but as the fine sands underneath begin to expose,the contribution of suspended load becomes significant.

关键词： beach evolution phase-averaged model wave-induced current storm surge morphodynamics

基于UPLC-Q TOF MS的狭叶番泻叶伪品耳叶番泻叶的特征成分发现及掺伪鉴别研究

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药物分析杂志 2024年第4期44卷 610-619页

作者：车爽周军杨文志李晓航赵晨郑新元天津市药品检验研究院天津300070 天津中医药大学中医药研究院天津301617

目的:采用高分辨质谱及组学分析技术分析狭叶番泻叶及耳叶番泻叶化学成分差异,并建立狭叶番泻叶中掺伪耳叶番泻叶的快速检查方法。方法:采用超高效液相色谱-四极杆飞行时间串联质谱(UPLC-Q TOF MS),分别采集13批狭叶番泻叶和9批耳叶番... 详细信息

目的:采用高分辨质谱及组学分析技术分析狭叶番泻叶及耳叶番泻叶化学成分差异,并建立狭叶番泻叶中掺伪耳叶番泻叶的快速检查方法。方法:采用超高效液相色谱-四极杆飞行时间串联质谱(UPLC-Q TOF MS),分别采集13批狭叶番泻叶和9批耳叶番泻叶的正谱和负谱MSE数据。采用Agilent ZORBAX SB-C18(100 mm×2.1 mm,1.8μm)色谱柱,柱温30℃,以乙腈(A)-1%乙酸(B)为流动相,流速0.3 mL·min^(-1),进样体积1μL;采集质量范围为m/z 50~1200。运用组学分析软件QI对狭叶番泻叶和耳叶番泻叶负谱数据进行正交偏最小二乘法判别分析,筛选出7个耳叶番泻叶特征性成分,并对其中的1个主要特征性成分进行了分离鉴定。进一步以主要特征性成分为指标性成分建立了快速检查狭叶番泻叶中掺伪耳叶番泻叶的UPLC方法,并应用于27批狭叶番泻叶样品及3批自制阳性样品的测定。结果:狭叶番泻叶和耳叶番泻叶的化学成分差异显著,经鉴定耳叶番泻叶中特有成分为kaempferol 3-O-(2”-O-apiofuranosyl)rutinoside。在狭叶番泻叶中掺伪耳叶番泻叶的UPLC检查方法中,该特有成分的精密度(RSD=1.3%)、重复性(RSD=1.3%)和稳定性(RSD=0.58%)均符合要求。27批狭叶番泻叶样品中23批未检出kaempferol 3-O-(2”-O-apiofuranosyl)rutinoside;4批狭叶番泻叶样品及3批自制阳性样品中检出kaempferol 3-O-(2”-O-apiofuranosyl)rutinoside。结论:本研究应用UPLC-Q TOF MS技术结合OPLS-DA分析方法成功将狭叶番泻叶和耳叶番泻叶进行了区分,分离并鉴定出耳叶番泻叶的主要特征性成分,并建立了快速筛查狭叶番泻叶中掺伪耳叶番泻叶的UPLC方法,为狭叶番泻叶的质量控制及质量标准的完善提供了依据,为中药材掺伪鉴别研究提供了思路和方法。

关键词：狭叶番泻叶耳叶番泻叶山柰酚3-O-(2”-O-阿哌呋喃基)芸香苷超高效液相色谱-四极杆/飞行时间串联质谱正交偏最小二乘法判别分析掺伪鉴别质量评价比较研究

The CUSUM statistic of change point under NA sequences

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Applied Mathematics(A Journal of Chinese Universities) 2021年第4期36卷 512-520页

作者： LING Jin LI Xiao-qin yang wen-zhi JIAO Jian-ling School of Management Hefei University of TechnologyHefei 230009China Center for Applied Mathematics School of Mathematical SciencesAnhui UniversityHefei 230061China

In this paper,we investigate the CUSUM statistic of change point under the neg-atively associated(NA)*** establishing the consistency estimators for mean and covariance functions respectively,the limit distribution of the CUSUM statistic is proved to be a standard Brownian bridge,which extends the results obtained under the case of an indepen-dent normal sample and the moving average ***,the finite sample properties of the CUSUM statistic are given to show the efficiency of the method by simulation studies and an application on a real data analysis.

关键词： CUSUM statistic limit distribution NA sequences Brownian bridge

Some new results for demimartingales

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Applied Mathematics(A Journal of Chinese Universities) 2011年第1期26卷 14-22页

作者： WANG Xue-jun HU Shu-he yang wen-zhi SHEN Yan chool of Mathematical Science Anhui University Hefei 230039 China

Harremoes obtained some new maximal inequalities for non-negative martingales. In this paper, we get some new maximal and minimal inequalities for non-negative demimartin- gales which generalize the results of Harremoes. We also obtain an inequality for non-negative demimartingales which generalizes the result of Iksanov and Marynych. Finally we obtain a strong law of large numbers, strong growth rate and integrability of supremum for demimartin- gales which generalize and improve the result of Chow.

关键词： Maximal inequality minimal inequality demimartingale strong law of large numbers.

Profiling and identification of chemical components of Shenshao Tablet and its absorbed components in rats by comprehensive HPLC/DAD/ESI-MS^n analysis

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Chinese Journal of Natural Medicines 2018年第10期16卷 791-800页

作者： MIAO wen-Juan HU Ying JIA Li ZHANG Chun-Xia yang wen-zhi ZHANG Ping GUO De-An Department of Pharmacy Institute of Hematology and Blood Disease HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin 300020China Tianjin State Key Laboratory of Modern Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjin 300193China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China

Shenshao Tablet(SST),prepared from Paeoniae Radix Alba(PRA)and total ginsenoside of Ginseng Stems and Leaves(GSL),is a traditional Chinese medicine(TCM)preparation prescribed to treat coronary heart ***,its chemical composition and the components that can migrate into blood potentially exerting the therapeutic effects have rarely been *** developed an HPLC/DAD/ESI-MS^n approach aiming to comprehensively profile and identify both the chemical components of SST and its absorbed ingredients(and metabolites)in rat plasma and *** separation was performed on an Agilent Eclipse XDB C_(18) column using acetonitrile/0.1% formic acid as the mobile *** detection was conducted in both negative and positive ESI modes to yield more structure *** with reference compounds(t_R,MS^n),interpretation of the fragmentation pathways,and searching of in-house database,were utilized for more reliable structure elucidation.A total of 82 components,including 21monoterpene glycosides,four galloyl glucoses,two phenols from PRA,and 55 ginsenosides from GSL,were identified or tentatively characterized from the 70% ethanolic extract of *** them,seven and 24 prototype compounds could be detectable in the plasma and urine samples,respectively,after oral administration of an SST extract(4 g×kg^(–1))in *** metabolites were observed in the rat *** findings of this work first unveiled the chemical complexity of SST and its absorbed components,which would be beneficial to understanding the therapeutic basis and quality control of SST.

关键词： Shenshao Tablet Paeoniae Radix Alba Total ginsenoside of Ginseng Stems and Leaves Chemical component

Adaptive joint configuration optimization for collaborative inference in edge-cloud systems

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Science China(Information Sciences) 2024年第4期67卷 335-336页

作者： Zheming yang wen JI zhi WANG Institute of Computing Technology Chinese Academy of Sciences University of Chinese Academy of Sciences Peng Cheng Laboratory Tsinghua Shenzhen International Graduate School Tsinghua University

With the rapid development of technologies such as deep learning and the Internet of Things(IoT), the deployment and application of various IoT devices are becoming increasingly widespread, resulting in the inference tasks generated increasing dramatically [1]. Many deep neural network(DNN) models are deployed on servers for performing inference tasks.

关键词： Inference engines

Effect of BaO and MgO on structure and properties of aluminate slag with various CaO/Al_(2)0_(3)ratios

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Journal of Iron and Steel Research International 2024年第1期31卷 204-214页

作者： Yu-qi Kong Ting Wu wen-zhi Xia wen yang Hai-chuan Wang School of Metallurgical Engineering Anhui University of TechnologyMa’anshan243032AnhuiChina Key Laboratory of Metallurgical Emission Reduction and Resource Recycling(Ministry of Education) Anhui University of TechnologyMa’anshan243002AnhuiChina

To provide theoretical guidance for performance stability control of low-reactive mold fluxes,the effects of BaO and MgO on the structure and properties of aluminate slag with various CaO/Al_(2)0_(3)(C/A)ratios were investigated using the Fourier transform infrared spectrometer,Raman spectroscope,hemispherical melting point instrument,rotational viscometer and X-ray *** results indicated that with BaO and MgO addition,the structure polymerization was first weakened and then enhanced at C/A of 1.1,and the transition contents corresponded to 8 wt.%BaO and 2 wt.%MgO,respectively,while the structure polymerization decreased continuously at C/A of *** the viscosity change was well consistent with the structure evolution,the polymerization degree played a more prominent role in the slag viscosity than superheat degree when the melting temperature difference was within 40℃.The break temperature decreased initially and then increased with augment of BaO and MgO at C/A of 1.1,while it manifested a decrease trend with BaO addition,and it decreased obviously but then turned to increase with MgO increment at C/A of *** crystallization phase and crystallization ratio kept stable with BaO increment,while the crystallization ratio rose greatly with MgO promoting LiAlO_(2)precipitation at C/A of *** crystal types of all experimental slags were mainly Ca_(12)Al_(14)O_(33)and CaF_(2)at C/A of 1.3,and the precipitation of crystalline phase BaAl2O4 demonstrated a rising trend,while that of Ca_(12)Al_(14)O_(33)gradually declined with BaO augment.

关键词： Aluminate slag Structure MgO BaO Viscosity Property

Numerical Modeling of the Undertow Structure and Sandbar Migration in the Surfzone

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China Ocean Engineering 2017年第5期31卷 549-558页

作者： XIE Ming-xiao ZHANG Chi yang zhi-wen LI Shan LI Xin GUO Wei-jun ZUO Shu-hua Key Laboratory of Engineering Sediment Tianjin Research Institute for Water Transport EngineeringM.O.T. National Engineering Laboratory for Port Hydraulic Construction Technology Tianjin Research Institute for Water Transport EngineeringM.O.T. State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Key Laboratory of Coastal Engineering Hydrodynamics of CCCC Tianjin Port Engineering InstituteCCCC College of Environmental Sciences and Engineering Dalian Maritime University

A process-based 3D numerical model for surfzone hydrodynamics and beach evolution was established. Comparisons between the experimental data and model results proved that the model could effectively describe the hydrodynamics, sediment transport feature and sandbar migration process in the surfzone with satisfactory precision. A series of numerical simulations on the wave breaking and shoaling up to a barred beach were carried out based on the model system. Analyzed from the model results, the wave-induced current system in the surfzone consists of two major processes, which are the phase-averaged undertow caused by wave breaking and the net drift caused by both of the nonlinear wave motion and surface roller effect. When storm waves come to the barred beach, the strong offshore undertow along the beach suppresses the onshore net drift, making the initial sandbar migrate to the seaside. Under the condition of calm wave environment, both the undertow and net drift flow to the shoreline at the offshore side of the sandbar, and then push the initial sandbar to the shoreline. The consideration of surface roller has significant impact on the modeling results of the sandbar migration. As the roller transfer rate increases, the sandbar moves onshore especially under the storm wave condition.

关键词： process-based numerical model undertow net driit sediment wansport sandbar migration