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基于UPLC-Q-TOF MS技术结合UNIFI软件快速筛查中药中非法添加调节性功能化合物
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作者 廖敏 王影超 +2 位作者 陈琪 姜莲 王海宁 《质谱学报》 北大核心 2025年第3期370-379,共10页
本研究采用超高效液相色谱-四极杆飞行时间质谱(UPLC-Q-TOF MS)技术结合UNIFI软件,建立了一种快速、准确检测中药中非法添加调节性功能化合物的方法。根据中药剂型的不同选择相应的样品制备方法,使用ACQUITY UPLC HSS T3色谱柱(2.1 mm&#... 本研究采用超高效液相色谱-四极杆飞行时间质谱(UPLC-Q-TOF MS)技术结合UNIFI软件,建立了一种快速、准确检测中药中非法添加调节性功能化合物的方法。根据中药剂型的不同选择相应的样品制备方法,使用ACQUITY UPLC HSS T3色谱柱(2.1 mm×100 mm,1.8μm),以乙腈-0.1%甲酸溶液为流动相进行梯度洗脱;在电喷雾离子源正离子模式下,使用MS^(E)模式采集数据。通过UNIFI软件建立靶向筛查数据库,并参考欧盟SANTE/11312/2021指南设定筛查条件,实现检测结果的自动化筛查。结果表明,本方法能够在12 min内快速筛查31种目标化合物,检出限为0.25~15.00 mg/kg(或mg/L)。在对20批次补肾壮阳类中药样品的检测中发现,7批次样品存在非法添加,其中4批次样品检出标准检测方法以外的化合物。该方法具有快速、准确、覆盖范围广且可灵活扩展的优点,可为中药中非法添加物的监管提供技术支持。 展开更多
关键词 超高效液相色谱-四极杆飞行时间质谱(UPLC-Q-TOF MS) unifi软件 中药 非法添加 调节性功能化合物 快速筛查
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基于UPLC-Q-TOF-MS/MS结合UNIFI的珠子参皂苷类化学成分分析及多指标含量测定 被引量:1
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作者 张苡嘉 杨婧潇 +4 位作者 胡新悦 黄嘉诚 王炜 刘乐平 严建业 《天然产物研究与开发》 北大核心 2025年第5期904-917,共14页
对珠子参中皂苷类成分进行定性鉴别分析,建立珠子参皂苷类多成分含量测定方法。采用超高效液相色谱-飞行时间质谱(UPLC-Q-TOF-MS/MS)技术对珠子参进行正、负离子模式扫描,使用UNIFI天然产物信息平台对珠子参所含的化学成分进行定性鉴别... 对珠子参中皂苷类成分进行定性鉴别分析,建立珠子参皂苷类多成分含量测定方法。采用超高效液相色谱-飞行时间质谱(UPLC-Q-TOF-MS/MS)技术对珠子参进行正、负离子模式扫描,使用UNIFI天然产物信息平台对珠子参所含的化学成分进行定性鉴别分析;以0.1%磷酸水-乙腈溶液为流动相进行梯度洗脱,柱温30℃,流速0.3 mL/min,进行珠子参皂苷类多成分含量测定。珠子参中共鉴定出39个化学成分,包括37个皂苷类化合物和2个皂苷母核,并总结了皂苷类化合物的裂解规律,建立了UPLC同时测定珠子参中人参皂苷Rb1、人参皂苷Ro、人参皂苷Rb3、竹节参皂苷IV、竹节参皂苷IVa、人参皂苷Rd、姜状三七皂苷R1和金盏花苷E的多指标含量测定方法,该方法中8个待测成分在检测质量浓度范围内线性关系良好,精密度、重复性、稳定性的相对标准偏差(relative standard deviation,RSD)均小于3.0%,样品中人参皂苷Rb1、人参皂苷Ro、人参皂苷Rb3、竹节参皂苷IV、竹节参皂苷IVa、人参皂苷Rd、姜状三七皂苷R1和金盏花苷E的平均加样回收率分别为102.4%、103.1%、97.97%、99.42%、102.7%、102.1%、95.23%、100.5%,RSD分别为1.0%、0.98%、0.81%、2.3%、0.81%、1.9%、0.96%、1.8%。该研究建立的方法可快速、准确地对珠子参中的皂苷类成分进行定性及定量分析。 展开更多
关键词 珠子参 UPLC-Q-TOF-MS/MS unifi 成分分析 含量测定
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Design of a Private Cloud Platform for Distributed Logging Big Data Based on a Unified Learning Model of Physics and Data 被引量:1
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作者 Cheng Xi Fu Haicheng Tursyngazy Mahabbat 《Applied Geophysics》 2025年第2期499-510,560,共13页
Well logging technology has accumulated a large amount of historical data through four generations of technological development,which forms the basis of well logging big data and digital assets.However,the value of th... Well logging technology has accumulated a large amount of historical data through four generations of technological development,which forms the basis of well logging big data and digital assets.However,the value of these data has not been well stored,managed and mined.With the development of cloud computing technology,it provides a rare development opportunity for logging big data private cloud.The traditional petrophysical evaluation and interpretation model has encountered great challenges in the face of new evaluation objects.The solution research of logging big data distributed storage,processing and learning functions integrated in logging big data private cloud has not been carried out yet.To establish a distributed logging big-data private cloud platform centered on a unifi ed learning model,which achieves the distributed storage and processing of logging big data and facilitates the learning of novel knowledge patterns via the unifi ed logging learning model integrating physical simulation and data models in a large-scale functional space,thus resolving the geo-engineering evaluation problem of geothermal fi elds.Based on the research idea of“logging big data cloud platform-unifi ed logging learning model-large function space-knowledge learning&discovery-application”,the theoretical foundation of unified learning model,cloud platform architecture,data storage and learning algorithm,arithmetic power allocation and platform monitoring,platform stability,data security,etc.have been carried on analysis.The designed logging big data cloud platform realizes parallel distributed storage and processing of data and learning algorithms.The feasibility of constructing a well logging big data cloud platform based on a unifi ed learning model of physics and data is analyzed in terms of the structure,ecology,management and security of the cloud platform.The case study shows that the logging big data cloud platform has obvious technical advantages over traditional logging evaluation methods in terms of knowledge discovery method,data software and results sharing,accuracy,speed and complexity. 展开更多
关键词 unified logging learning model logging big data private cloud machine learning
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超高效液相色谱-四极杆-飞行时间高分辨质谱技术结合UNIFI高通量筛查面膜类化妆品中141种非法添加成分
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作者 范晨丽 王海波 +1 位作者 蒋培 申二永 《分析科学学报》 北大核心 2025年第4期405-414,共10页
建立了一种基于超高效液相色谱-四极杆-飞行时间高分辨质谱技术,结合UNIFI软件的高通量筛查方法,用于检测面膜类化妆品中141种非法添加成分。样品经饱和氯化钠溶液溶解后,加入含0.5%甲酸的乙腈进行超声提取,采用Oasis HLB固相萃取小柱... 建立了一种基于超高效液相色谱-四极杆-飞行时间高分辨质谱技术,结合UNIFI软件的高通量筛查方法,用于检测面膜类化妆品中141种非法添加成分。样品经饱和氯化钠溶液溶解后,加入含0.5%甲酸的乙腈进行超声提取,采用Oasis HLB固相萃取小柱净化。使用BEH C18(100 mm×2.1 mm,1.7μm)色谱柱分离,并在电喷雾离子源(ESI)正负扫描模式下,采用MS^(E)模式采集化合物的质谱信息。通过化合物的母离子和二级碎片离子的精准质量数以及保留时间等参数,利用UNIFI软件构建筛查数据库。最终通过基质标曲外标法进行定量分析。141种非法添加成分响应值与浓度呈良好线性关系(R^(2)>0.99),检出限为0.15~1.35 mg/kg;定量限为0.45~4.05 mg/kg。空白基质样品(面贴式乳液剂和涂抹式膏霜剂)中加入3个水平点的平均回收率为63.0%~124.5%;日内、日间相对标准偏差(RSD)分别为1.2%~9.1%(n=6)和1.3%~13.9%(n=3)。采用该方法测定市售86批面膜类产品,检出1批氯倍他索丙酸脂和3批酮康唑,检出含量范围为0.3~561.3 mg/kg。该方法操作简便、高效准确,具有良好的专属性,可实现面膜类化妆品中141种非法添加成分的高通量筛查,为化妆品质量监管提供了可靠的技术支持。 展开更多
关键词 UPLC-Q-TOF-MS^(E) 面膜类化妆品 非法添加成分 unifi 高通量筛查
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Towards Efficient Vehicle Recognition:A Unified System for VMMR,ANPR,and Color Classification
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作者 Saad Sadiq Kashif Sultan +2 位作者 Muhammad Sheraz Teong Chee Chuah Muhammad Usman Hashmi 《Computers, Materials & Continua》 2025年第11期3945-3963,共19页
Vehicle recognition plays a vital role in intelligent transportation systems,law enforcement,access control,and security operations—domains that are becoming increasingly dynamic and complex.Despite advancements,most... Vehicle recognition plays a vital role in intelligent transportation systems,law enforcement,access control,and security operations—domains that are becoming increasingly dynamic and complex.Despite advancements,most existing solutions remain siloed,addressing individual tasks such as vehicle make and model recognition(VMMR),automatic number plate recognition(ANPR),and color classification separately.This fragmented approach limits real-world efficiency,leading to slower processing,reduced accuracy,and increased operational costs,particularly in traffic monitoring and surveillance scenarios.To address these limitations,we present a unified framework that consolidates all three recognition tasks into a single,lightweight system.The framework utilizes MobileNetV2 for efficient VMMR,YOLO(You Only Look Once)for accurate license plate detection,and histogram-based clustering in the HSV color space for precise color identification.Rather than optimizing each module in isolation,our approach emphasizes tight integration,enabling improved performance and reliability.The system also features adaptive image calibration and robust algorithmic enhancements to ensure consistent results under varying environmental conditions.Experimental evaluations demonstrate that the proposedmodel achieves a combined accuracy of 93.3%,outperforming traditional methods and offering practical scalability for deployment in real-world transportation infrastructures. 展开更多
关键词 VMMR ANPR unified framework deep learning
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Unified construction of prenylated and reverse-prenylated oxindoles from isoprene launched by Ni catalysis
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作者 Ying-Ying Liu Ying Li +4 位作者 Xue-Ting Li Su-Yang Xu Ding-Wei Ji Xiang-Ping Hu Qing-An Chen 《Chinese Journal of Catalysis》 2025年第3期444-454,共11页
As important natural and pharmaceutical motifs,the catalytic construction of structurally diverse 3,3-disubstituted oxindoles often requires elaborate synthetic efforts on optimizations.Herein,we developed a simple an... As important natural and pharmaceutical motifs,the catalytic construction of structurally diverse 3,3-disubstituted oxindoles often requires elaborate synthetic efforts on optimizations.Herein,we developed a simple and divergent approach for constructing reverse-prenylated and prenylated oxindoles launched by Ni catalysis with bulk chemical isoprene.Using C3-unsubstituted oxindoles as starting materials,mono reverse-prenylation was demonstrated in high chemo-and regioselectivities facilitated by the combination of Ni(0)and monodentate phosphine ligand.Using the obtained reverse-prenylated oxindoles as versatile synthon,substitutions at the pseudobenzylic position with various electrophiles created vicinal quaternary centers in a concise way.With the help of additives(PPh3 and NaH),air could be directly used as green oxidant to construct prenylated and reverse-prenylatedα-hydroxy-oxindoles divergently from the same substrates.In situ esterification of prenylatedα-hydroxy-oxindoles allowed subsequent Friedel-Crafts substitutions with diverse nucleophiles to deliver prenyl substituted dimeric or spiro-oxindoles.This protocol provides a divergent synthetic approach for the construction of highly functionalized 3,3-disubstituted oxindoles,which have been otherwise difficult to access in a unified approach. 展开更多
关键词 Nickel catalysis unified construction ISOPRENE (Reverse-)prenylation OXINDOLE
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Ground reaction curves for strain-softening rock masses with ground reinforcement based on unified strength criterion
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作者 CHEN Xuan-hao ZHANG Ding-li +1 位作者 SUN Zhen-yu CHEN Wen-bo 《Journal of Central South University》 2025年第9期3383-3404,共22页
Ground reinforcement is crucial for tunnel construction, especially in soft rock tunnels. Existing analytical models are inadequate for predicting the ground reaction curves (GRCs) for reinforced tunnels in strain-sof... Ground reinforcement is crucial for tunnel construction, especially in soft rock tunnels. Existing analytical models are inadequate for predicting the ground reaction curves (GRCs) for reinforced tunnels in strain-softening (SS) rock masses. This study proposes a novel analytical model to determine the GRCs of SS rock masses, incorporating ground reinforcement and intermediate principal stress (IPS). The SS constitutive model captures the progressive post- peak failure, while the elastic-brittle model simulates reinforced rock masses. Nine combined states are innovatively investigated to analyze plastic zone development in natural and reinforced regions. Each region is analyzed separately, and coupled through boundary conditions at interface. Comparison with three types of existing models indicates that these models overestimate reinforcement effects. The deformation prediction errors of single geological material models may exceed 75%. Furthermore, neglecting softening and residual zones in natural regions could lead to errors over 50%. Considering the IPS can effectively utilize the rock strength to reduce tunnel deformation by at least 30%, thereby saving on reinforcement and support costs. The computational results show a satisfactory agreement with the monitoring data from a model test and two tunnel projects. The proposed model may offer valuable insights into the design and construction of reinforced tunnel engineering. 展开更多
关键词 ground reinforcement STRAIN-SOFTENING unified strength criterion tunnel responses analytical model
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Stress gradient analytic solution and reasonable support prestress of roadway surrounding rock based on unified strength criterion:A case study
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作者 JING Suo-lin WEN Zhi-jie +2 位作者 ZUO Yu-jun LI Qiu-ju HAO Peng 《Journal of Central South University》 2025年第2期449-468,共20页
The stress gradient of surrounding rock and reasonable prestress of support are the keys to ensuring the stability of roadways.The elastic-plastic analytical solution for surrounding rock was derived based on unified ... The stress gradient of surrounding rock and reasonable prestress of support are the keys to ensuring the stability of roadways.The elastic-plastic analytical solution for surrounding rock was derived based on unified strength theory.A model for solving the stress gradient of the surrounding rock with the intermediate principal stress parameter b was established.The correctness and applicability of the solution for the stress gradient in the roadway surrounding rock was verified via multiple methods.Furthermore,the laws of stress,displacement,and the plastic zone of the surrounding rock with different b values and prestresses were revealed.As b increases,the stress gradient in the plastic zone increases,and the displacement and plastic zone radius decrease.As the prestress increases,the peak stress shifts toward the sidewalls,and the stress and stress gradient increments decrease.In addition,the displacement increment and plastic zone increment were proposed to characterize the support effect.The balance point of the plastic zone area appears before that of the displacement zone.The relationship between the stress gradient compensation coefficient and the prestress is obtained.This study provides a research method and idea for determining the reasonable prestress of support in roadways. 展开更多
关键词 PRESTRESS support compensation surrounding rock damage stress gradient analytic solution unified strength theory
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Modeling the significance of unified theory of acceptance and use of technology in predicting the intention and usage of eCNY
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作者 Yue Ma Abdullah Al Mamun +1 位作者 Mohammad Masukujjaman Roslan Ja’afar 《Financial Innovation》 2025年第1期504-535,共32页
The introduction of the digital renminbi(eCNY)by the People’s Bank of China serves as a means for the central bank to effectively comprehend macroeconomic dynamics and enhance payment infrastructure within the domest... The introduction of the digital renminbi(eCNY)by the People’s Bank of China serves as a means for the central bank to effectively comprehend macroeconomic dynamics and enhance payment infrastructure within the domestic market.Among the pioneering digital currencies,the eCNY is at the forefront of technological research and development,pilot implementation,and the establishment of a robust system.Thus,employing the unified theory of acceptance and use of technology,this study aims to explore the factors shaping the adoption of the eCNY and to determine the mediating effects of intention toward the eCNY and the moderating role of age and gender among various relationships.A cross-sectional survey methodology was deployed to collect data from pilot communities situated within the Yangtze River Delta,Pearl River Delta,and Beijing–Tianjin–Hebei regions.The empirical analysis comprised 809 valid online questionnaires,and the examination was conducted through structural equation modeling employing the partial least squares technique,ultimately subjecting the conceptual model to a comprehensive assessment.The results for intention to use the eCNY indicate that performance expectancy,effort expectancy,social influence,and perceived government policy have significant effects.Facilitating conditions and intentions toward the eCNY positively influenced its actual use.According to the findings of this study,age and sex did not moderate the effect of each hypothesis on the intention to use in the research model.This study breaks new ground by investigating the adoption of the eCNY,a novel form of currency,highlighting its multifaceted nature and providing empirical evidence for a comprehensive model encompassing psychological,social,and contextual factors.This study employs social surveys to identify obstacles in the process of promoting the widespread adoption of the eCNY and offers suggestions to the central bank and government to increase user enthusiasm and decrease user perceptions of risk,thereby promoting its widespread adoption. 展开更多
关键词 Digital currency eCNY Intention and actual usage unified theory of acceptance Use of technology
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Two imaginarity monotones induced by unified(α,β)-relative entropy
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作者 Chuanfa Wu Zhaoqi Wu 《Communications in Theoretical Physics》 2025年第9期24-34,共11页
Complex numbers play a pivotal role in both mathematics and physics,particularly in quantum mechanics,and are extensively utilized to depict the behavior of microscopic particles.Recognizing the significance of comple... Complex numbers play a pivotal role in both mathematics and physics,particularly in quantum mechanics,and are extensively utilized to depict the behavior of microscopic particles.Recognizing the significance of complex numbers,a framework of imaginarity resource theory has recently been established.In this work,we propose two types of imaginarity monotones induced by the unified(α,β)-relative entropy and investigate their properties.Moreover,we give explicit examples to illustrate our results. 展开更多
关键词 quantum resource theory imaginarity monotone unified(α β)-relative entropy
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Associated network family of the unified piecewise linear chaotic family and their relevance
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作者 Haoying Niu Jie Liu 《Chinese Physics B》 2025年第4期323-333,共11页
Duality analysis of time series and complex networks has been a frontier topic during the last several decades.According to some recent approaches in this direction,the intrinsic dynamics of typical nonlinear systems ... Duality analysis of time series and complex networks has been a frontier topic during the last several decades.According to some recent approaches in this direction,the intrinsic dynamics of typical nonlinear systems can be better characterized by considering the related nonlinear time series from the perspective of networks science.In this paper,the associated network family of the unified piecewise-linear(PWL)chaotic family,which can bridge the gap of the PWL chaotic Lorenz system and the PWL chaotic Chen system,was firstly constructed and analyzed.We constructed the associated network family via the original and the modified frequency-degree mapping strategy,as well as the classical visibility graph and horizontal visibility graph strategy,after removing the transient states.Typical related network characteristics,including the network fractal dimension,of the associated network family,are computed with changes of single key parameter a.These characteristic vectors of the network are also compared with the largest Lyapunov exponent(LLE)vector of the related original dynamical system.It can be found that,some network characteristics are highly correlated with LLE vector of the original nonlinear system,i.e.,there is an internal consistency between the largest Lyapunov exponents,some typical associated network characteristics,and the related network fractal dimension index.Numerical results show that the modified frequency-degree mapping strategy can demonstrate highest correlation,which means it can behave better to capture the intrinsic characteristics of the unified PWL chaotic family. 展开更多
关键词 nonlinear time series unified PWL chaotic family Lyapunov exponents complex network
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UPLC-Q-TOF MS^E技术结合UNIFI数据库筛查方法快速分析巴戟天化学成分 被引量:21
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作者 王美玲 张清清 +8 位作者 付爽 刘月红 梁钏镭 陈娜 丁永胜 王海丽 瞿晓梅 赵保胜 高晓燕 《质谱学报》 EI CAS CSCD 北大核心 2017年第1期75-82,共8页
采用UPLC-Q-TOF MS^E技术结合UNIFI数据库筛查方法对巴戟天中的化学成分进行了快速鉴定。对于已知化合物,利用其名称、分子式、结构式等信息补充完善UNIFI数据库,进行数据筛查,依据其精确分子质量、特征离子、中性丢失、MS/MS裂解规律... 采用UPLC-Q-TOF MS^E技术结合UNIFI数据库筛查方法对巴戟天中的化学成分进行了快速鉴定。对于已知化合物,利用其名称、分子式、结构式等信息补充完善UNIFI数据库,进行数据筛查,依据其精确分子质量、特征离子、中性丢失、MS/MS裂解规律、色谱保留行为等信息,结合对照品信息和文献报道等对其进行验证;对于未知成分,根据其精确分子质量、质谱裂解碎片、色谱保留行为以及已知同类化合物的特征碎片,对其进行结构表征。本实验共鉴定出110个化合物,包括8个寡糖类、12个环烯醚萜类、58个蒽醌类化合物和32个其他类化合物;推断出8个未知化合物,包括1个有机酸、2个苷类化合物、5个环烯醚萜类成分,其中4个是潜在的新化合物,另外4个为巴戟天中首次发现的化合物。该方法可对巴戟天药材中的化学成分进行快速、全面的分析,为巴戟天药材的质量控制和药效物质基础研究奠定基础。 展开更多
关键词 UPLC-Q-TOF MSE unifi数据库 巴戟天 快速鉴定 表征
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UPLC-Q-TOF-MS^E技术结合UNIFI数据库快速定性分析黄牡丹化学成分 被引量:24
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作者 李金花 曾锐 +1 位作者 瞿燕 黄林芳 《中草药》 CAS CSCD 北大核心 2017年第8期1529-1536,共8页
目的应用超高效液相色谱仪联用四级杆串联飞行时间质谱仪(UPLC-Q-TOF-MSE)结合UNIFI天然产物信息平台对黄牡丹Paeonia delavayi var.lutea的化学成分进行快速定性分析。方法应用时间依赖型MSE方式采集样品质谱数据,结合自动检出及人工... 目的应用超高效液相色谱仪联用四级杆串联飞行时间质谱仪(UPLC-Q-TOF-MSE)结合UNIFI天然产物信息平台对黄牡丹Paeonia delavayi var.lutea的化学成分进行快速定性分析。方法应用时间依赖型MSE方式采集样品质谱数据,结合自动检出及人工核对方法分析黄牡丹化学成分。结果通过UNIFI数据库自动检出、在线及离线数据库的检索和相关文献的人工核对,鉴定了57个化合物,包括单萜苷、酚酸、鞣酸、丹皮酚和三萜等类化合物。结论本方法可以快速全面地定性分析黄牡丹根的化学成分,为黄牡丹的质量控制和药效物质基础的阐明提供参考。 展开更多
关键词 黄牡丹 高效液相色谱仪联用四级杆串联飞行时间质谱仪 unifi 单萜苷 酚酸 鞣酸 丹皮酚
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UPLC-Q-TOF-MS^E技术结合UNIFI软件分析黄地安消胶囊化学成分 被引量:18
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作者 高家荣 朱梦情 +3 位作者 汪小莉 吴欢 单莉 王云 《中国中药杂志》 CAS CSCD 北大核心 2020年第10期2395-2405,共11页
为了明确黄地安消胶囊的主要化学成分,该研究采用超高效液相色谱串联四极杆飞行时间质谱联用技术(UPLC-Q-TOF-MS^E)结合WatersUNIFI软件对黄地安消胶囊的化学成分进行快速定性分析。通过UPLC-Q-TOF-MS^E技术采集黄地安消胶囊的质谱数据... 为了明确黄地安消胶囊的主要化学成分,该研究采用超高效液相色谱串联四极杆飞行时间质谱联用技术(UPLC-Q-TOF-MS^E)结合WatersUNIFI软件对黄地安消胶囊的化学成分进行快速定性分析。通过UPLC-Q-TOF-MS^E技术采集黄地安消胶囊的质谱数据,根据UNIFI软件匹配的结果,结合对照品的保留时间、特征碎片和文献数据进行比对,共鉴定和推测出100个化合物,25个归属于葛根、22个归属于黄连、6个归属于麦冬、14个归属于枇杷叶、22个归属于生地黄、15个归属于三七,其中有3个化合物为共有成分。所测得的成分包含黄酮类成分、生物碱类成分、皂苷类成分、有机酸类成分等。该研究系统地分析了黄地安消胶囊的化学成分,为阐明黄地安消胶囊的药效物质基础提供了依据。 展开更多
关键词 黄地安消胶囊 UPLC-Q-TOF-MS^E unifi 化学成分
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Unified Solution Method of Rectangular Plate Elastic Bending 被引量:9
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作者 许琪楼 姬同庚 +2 位作者 姜锐 唐国明 姬鸿恩 《Journal of Southeast University(English Edition)》 EI CAS 2002年第3期241-248,共8页
The bending of rectangular plate is divided into the generalized statically determinate bending and the generalized statically indeterminate bending based on the analysis of the completeness of calculating condition a... The bending of rectangular plate is divided into the generalized statically determinate bending and the generalized statically indeterminate bending based on the analysis of the completeness of calculating condition at the corner point. The former can be solved directly by the equilibrium differential equation and the boundary conditions of four edges of the plate. The latter can be solved by using the superposition principle. Making use of the recommended method, the bending of the plate with all kinds of... 展开更多
关键词 bending of elastic thin plate rectangular plate unified solution method
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UPLC-Q-TOF-MS^E技术结合UNIFI数据库快速定性分析补气通络颗粒的化学成分 被引量:11
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作者 黄壮壮 刘峰 +3 位作者 孙宇宏 丁腾 程薇薇 苏英英 《西北药学杂志》 CAS 2019年第4期477-483,共7页
目的应用超高效液相色谱联用四级杆飞行时间质谱仪(UPLC-Q-TOF-MS^E)结合UNIFI数据平台对补气通络颗粒的化学成分进行快速定性分析。方法应用时间依赖型MSE法采集样品质谱数据,结合自动检出及人工核对方法分析补气通络颗粒的化学成分。... 目的应用超高效液相色谱联用四级杆飞行时间质谱仪(UPLC-Q-TOF-MS^E)结合UNIFI数据平台对补气通络颗粒的化学成分进行快速定性分析。方法应用时间依赖型MSE法采集样品质谱数据,结合自动检出及人工核对方法分析补气通络颗粒的化学成分。结果通过UNIFI数据库自动检测结果、搜索在线和离线数据库以及人工核对相关文献,鉴定黄酮类、皂苷类、萜类、酯类、氨基酸和酚酸类共72种化合物。其中,7种来自红芪,14种来自三七,24种来自泽泻,9种来自当归,2种来自川芎,6种来自蝉蜕,6种来自郁金,4种来自桂枝。结论本方法可快速定性分析补气通络颗粒的多种化学成分,为补气通络颗粒的质量控制、药效物质基础解析、作用机制阐明和组分配伍中药的开发提供参考。 展开更多
关键词 补气通络颗粒 UPLC-Q-TOF-MS^E unifi数据库
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UPLC-Q-TOF-MS^(E)技术结合UNIFI筛查平台分析加味逍遥丸化学成分 被引量:5
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作者 孙健 刘子维 +9 位作者 刘莹 张美玉 李孟莹 张海鸣 聂颖兰 权建野 闫寒 彭娟 栗俞程 杨书彬 《中国药物警戒》 2023年第2期181-190,共10页
目的运用高效液相色谱-四极杆-飞行时间串联质谱法(UPLC-Q-TOF-MS^(E))对加味逍遥丸的化学成分进行分析与鉴定,为复方质量控制及药效物质基础研究提供理论依据。方法采用ACQUITY UPLC BEH C_(18)柱(2.1 mm×100 mm,1.7μm,Waters),... 目的运用高效液相色谱-四极杆-飞行时间串联质谱法(UPLC-Q-TOF-MS^(E))对加味逍遥丸的化学成分进行分析与鉴定,为复方质量控制及药效物质基础研究提供理论依据。方法采用ACQUITY UPLC BEH C_(18)柱(2.1 mm×100 mm,1.7μm,Waters),以0.1%甲酸水-乙腈为流动相,梯度洗脱,进样量5μL,流速0.3 mL·min^(-1),柱温40℃。采用电喷雾离子源,在正、负2种模式下进行复方质谱检测与分析,并且使用UNIFI平台对MS^(E)模式下采集的质谱数据,结合化合物准分子离子、质谱裂解途径及标准品进行结构确认。结果通过分析目标化合物的分子离子峰和二级质谱特征碎片离子,并且结合标准品裂解规律以及相关文献资料,共鉴定了其中78个化学成分,包括3个倍半萜类成分、4个苯丙素类成分、13个单萜类成分、7个酚类成分、5个环烯醚萜类成分、10个黄酮类成分、23个三萜类成分及13个其他类成分。结论运用UPLC-Q-TOF-MS^(E)技术可快速分析鉴定复方加味逍遥丸的主要化合物类型,可为复方质量控制及药效物质基础研究提供理论依据。 展开更多
关键词 加味逍遥丸 高效液相色谱-四级杆-飞行时间串联质谱法(UPLC-Q-TOF-MS^(E)) 化学成分 unifi平台
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Micro-macro Unified Analysis of Flow Behavior of Particle-reinforced Metal Matrix Composites 被引量:2
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作者 张鹏 李付国 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2010年第2期252-259,共8页
This article presents a micro-macro unified model for predicting the deformation of metal matrix composites (MMCs). A macro-scale model is developed to obtain the proper boundary conditions for the micro-scale model... This article presents a micro-macro unified model for predicting the deformation of metal matrix composites (MMCs). A macro-scale model is developed to obtain the proper boundary conditions for the micro-scale model, which is used to assess the microstructural deformation of materials. The usage of the submodel technique in the analysis makes it possible to shed light on the stress and strain field at the microlevel. This is helpful to investigate the linkage between the microscopic and the macroscopic flow behavior of the composites. An iterative procedure is also proposed to find out the optimum parameters. The results show that the convergence can be attained after three iterations in computation. In order to demonstrate the reliability of mi- cro-macro unified model, results based on the continuum composite model are also investigated using the stress-strain relation of composite obtained from the iterations. By comparing the proposed unified model to the continuum composite model, it is clear that the former exhibits large plastic deformation in the case of little macroscopic deformation, and the stresses and strains obtained from the submodel are higher than those from the macroscopic deformation. 展开更多
关键词 metal matrix composites micro-macro unified model submodel flow behavior MICROSTRUCTURE
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Analysis of plane strain bending of a strain hardening curved beam based on unified yield criterion 被引量:1
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作者 傅军 庞苗 +2 位作者 宋广远 张永强 杨博 《Journal of Southeast University(English Edition)》 EI CAS 2016年第3期339-345,共7页
The analysis of plane strain elastic-plastic bending of a linear strain hardening curved beam with a narrow rectangular cross section subjected to couples at its end is conducted based on a unified yield criterion. Th... The analysis of plane strain elastic-plastic bending of a linear strain hardening curved beam with a narrow rectangular cross section subjected to couples at its end is conducted based on a unified yield criterion. The solutions for the mechanical properties of plane strain bending are derived, which are adapted for various kinds of non-strength differential materials and can be degenerated to those based on the Tresca, von Mises, and twin-shear yield criteria. The dependences of the two critical bending moments, the radii of the interfaces between the elastic and plastic regions and the radial displacements of the points at the symmetrical plane on different yield criteria and Poisson’s ratios are discussed. The results show that the influences of different yield criteria and Poisson’s ratio on the two critical bending moments, the radii of the interfaces between the elastic and plastic regions and the radial displacements of the points at the symmetrical plane of the curved beam are significant. Once the value of bis obtained by experiments, the yield criterion and the corresponding solution for the materials of interest are then determined. 展开更多
关键词 curved beam plane strain strain hardening elastic-plastic bending unified yield criterion
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基于OPC Unified Architecture的服务器研究 被引量:8
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作者 孙发 刘枫 《仪器仪表标准化与计量》 2006年第5期14-17,共4页
首先介绍现有OPC规范以及其存在的不足,然后介绍OPC基金会即将推出的OPCUnifiedArchitecture规范,并重点研究OPCUnifiedArchitecture服务器的实现机制及方法,通过与现有OPC规范的比较,揭示OPCUA在平台无关性、可互操作性、可靠性等方面... 首先介绍现有OPC规范以及其存在的不足,然后介绍OPC基金会即将推出的OPCUnifiedArchitecture规范,并重点研究OPCUnifiedArchitecture服务器的实现机制及方法,通过与现有OPC规范的比较,揭示OPCUA在平台无关性、可互操作性、可靠性等方面的显著优势。 展开更多
关键词 OPC OPC unifiED ARCHITECTURE 可互操作
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