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基于UPLC-Triple-TOF-MS技术初步分析雅安产道地中药材川牛膝中生物碱成分
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作者 王悦秋 王昌 +1 位作者 梁林辉 梁大伟 《山东化工》 CAS 2024年第3期155-157,160,共4页
采用乙醇提取、成盐、二氯甲烷萃取等方法初步富集川牛膝总生物碱,确定最优提取分离工艺;通过超高液相色谱串联三重四级杆飞行时间质谱法,采用Waters XSelect CSH-C_(18)色谱柱(2.1 mm×150 mm,1.7μm),梯度洗脱,流速为0.3 mL/min,... 采用乙醇提取、成盐、二氯甲烷萃取等方法初步富集川牛膝总生物碱,确定最优提取分离工艺;通过超高液相色谱串联三重四级杆飞行时间质谱法,采用Waters XSelect CSH-C_(18)色谱柱(2.1 mm×150 mm,1.7μm),梯度洗脱,流速为0.3 mL/min,测试波长254 nm,柱温为50℃,进样量为3μL,采用电喷雾离子源正离子模式,扫描范围为m/z 100~1500,并采用全扫描模式对样品数据进行收集,根据高分辨质谱结合二级质谱所得信息对川牛膝中生物碱类化学成分进行快速鉴定,通过对比分子离子峰和碎片离子的质荷比、Scifinder和Reaxy数据库及相关文献,推测出两种生物碱成分。研究建立的生物碱类化学成分提取与分析方法,为提高雅安产道地中药材川牛膝的质量控制水平及后续阐明药效物质基础提供了实验依据。 展开更多
关键词 川牛膝 生物碱 提取方法 超高液相色谱串联三重四级杆飞行时间质谱法 定性分析
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一类特殊的完备左对称代数的导子与triple导子
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作者 吴孟珂 吴明忠 《湖州师范学院学报》 2024年第2期1-7,共7页
利用导子和triple导子的定义,通过计算线性变换在一组基下的结果,得到与Abelian李代数相容的维数小于或等于4维的完备左对称代数的导子,以及triple导子的矩阵形式.
关键词 左对称代数 Abelian李代数 相容 导子 triple导子
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改良Kite技术联合Triple-button治疗急性肩锁关节脱位
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作者 任晓伟 吴羽 +2 位作者 李艳军 罗浩 马战备 《实用骨科杂志》 2024年第8期696-700,共5页
目的探讨关节镜下采用改良Kite技术联合Triple-button治疗肩锁关节脱位的临床疗效。方法回顾性分析2019年12月至2022年5月保定市第一中心医院与北京大学第三医院采用关节镜下改良Kite技术结合Triple-button治疗急性肩锁关节脱位的33例... 目的探讨关节镜下采用改良Kite技术联合Triple-button治疗肩锁关节脱位的临床疗效。方法回顾性分析2019年12月至2022年5月保定市第一中心医院与北京大学第三医院采用关节镜下改良Kite技术结合Triple-button治疗急性肩锁关节脱位的33例患者资料。其中男21例,女12例;年龄21~58岁,平均(38.22±0.60)岁;左肩20例,右肩13例;Rockwood分型:Ⅲ型16例,Ⅴ型17例。记录患者术前、末次随访疼痛视觉模拟评分(visual analogue scale,VAS)、患侧肩关节Constant-Murley评分、肩关节前屈上举活动度(range of motion,ROM),正位X线片上测量喙突锁骨间距(coracoclavicular distance,CCD)、肩峰锁骨间距(acromioclavicular distance,ACD),记录并发症情况。结果33例患者均获得随访,随访时间6~19个月,平均(13.36±0.28)个月。患者切口均甲级愈合,无肩锁关节再脱位、锁骨和喙突骨折等并发症。VAS评分术前(7.44±0.53)分,末次随访(0.56±0.73)分,差异有统计学意义(P<0.001)。Constant-Murley评分术前(35.11±1.45)分,末次随访(90.11±2.80)分,差异有统计学意义(P<0.001)。术前肩关节前屈上举(47.22±9.39)°,末次随访(178.89±3.33)°,差异有统计学意义(P<0.001)。术前CCD为(16.73±3.73)mm,末次随访(10.61±3.24)mm,差异有统计学意义(P<0.05)。术前ACD为(12.18±3.34)mm,末次随访(6.49±2.64)mm,差异有统计学意义(P<0.001)。结论关节镜下改良Kite技术结合Triple-button治疗肩锁关节脱位安全可重复,可以获得满意的近期临床疗效,其远期疗效仍需观察。 展开更多
关键词 肩锁关节脱位 Kite技术 喙锁韧带 关节镜 triple-button
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A robust low-friction triple network hydrogel based on multiple synergistic enhancement mechanisms
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作者 Xinyue ZHANG Qin CHEN +4 位作者 Kai CHEN Cunao FENG Haiyan FENG Xiaowei LI Dekun ZHANG 《Friction》 SCIE EI CAS CSCD 2024年第12期2726-2740,共15页
Hydrogels exhibit promising applications,particularly due to their high water content and excellent biocompatibility.Despite notable progress in hydrogel technology,the concurrent enhancement of water content,mechanic... Hydrogels exhibit promising applications,particularly due to their high water content and excellent biocompatibility.Despite notable progress in hydrogel technology,the concurrent enhancement of water content,mechanical strength,and low friction poses substantial challenges to practical utilization.In this study,employing molecular and network design guided based on multiple synergistic enhancement mechanisms,we have developed a robust polyvinyl alcohol(PVA)-polyacrylic acid(PAA)-polyacrylamide(PAAm)three-network(TN)hydrogel exhibiting high water content,enhanced strength,low friction,and fatigue resistance.The hydrogel manifests a water content of 63.7%,compression strength of 6.3 MPa,compression modulus of 2.68 MPa,tensile strength reaching 7.3 MPa,and a tensile modulus of 10.27 MPa.Remarkably,even after one million cycles of dynamic loading,the hydrogel exhibits no signs of fatigue failure,with a minimal strain difference of only 1.15%.Furthermore,it boasts a low sliding coefficient of friction(COF)of 0.043 and excellent biocompatibility.This advancement extends the applications of hydrogels in emerging fields within biomedicine and soft bio-devices,including load-bearing artificial tissues,artificial blood vessels,tissue scaffolds,robust hydrogel coatings for medical devices,and joint parts of soft robots. 展开更多
关键词 triple network water content mechanical properties tribological behavior
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Triple points and phase transitions of D-dimensional dyonic Ad S black holes with quasitopological electromagnetism in Einstein–Gauss–Bonnet gravity
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作者 牟平辉 蒋青权 +1 位作者 何柯腱 李国平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期272-287,共16页
By considering the negative cosmological constant Λ as a thermodynamic pressure, we study the thermodynamics and phase transitions of the D-dimensional dyonic Ad S black holes(BHs) with quasitopological electromagnet... By considering the negative cosmological constant Λ as a thermodynamic pressure, we study the thermodynamics and phase transitions of the D-dimensional dyonic Ad S black holes(BHs) with quasitopological electromagnetism in Einstein–Gauss–Bonnet(EGB) gravity. The results indicate that the small/large BH phase transition that is similar to the van der Waals(vdW) liquid/gas phase transition always exists for any spacetime dimensions. Interestingly, we then find that this BH system exhibits a more complex phase structure in 6-dimensional case that is missed in other dimensions.Specifically, it shows for D = 6 that we observed the small/intermediate/large BH phase transitions in a specific parameter region with the triple point naturally appeared. Moreover, when the magnetic charge turned off, we still observed the small/intermediate/large BH phase transitions and triple point only in 6-dimensional spacetime, which is consistent with the previous results. However, for the dyonic Ad S BHs with quasitopological electromagnetism in Einstein–Born–Infeld(EBI) gravity, the novel phase structure composed of two separate coexistence curves observed by Li et al. [Phys. Rev. D105 104048(2022)] disappeared in EGB gravity. This implies that this novel phase structure is closely related to gravity theories, and seems to have nothing to do with the effect of quasitopological electromagnetism. In addition, it is also true that the critical exponents calculated near the critical points possess identical values as mean field theory. Finally, we conclude that these findings shall provide some deep insights into the intriguing thermodynamic properties of the dyonic Ad S BHs with quasitopological electromagnetism in EGB gravity. 展开更多
关键词 AdS black hole phase transition triple point
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A Cross-Sectional Study on the Impact of Operation Triple Zero (OTZ) Program on Viral Load Suppression amongst Members of the Adolescent Club in 68 Nigerian Army Reference Hospital Yaba Lagos, Nigeria
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作者 Nkechinyere Harrison Ismail Lawal +7 位作者 Yakubu Adamu Kehinde Aribisala Adegbenga Olarinoye Uzoamaka Agbaim Funmilayo Owolabi Dooshima Okonkwo Laura Chittenden Nathan Okeji 《World Journal of AIDS》 2024年第2期35-44,共10页
Background: In Nigeria, adolescents and young people (AYP) aged 10 - 24, comprise 22.3% of the population and with HIV prevalence of 3.5%. The AYP living with HIV enrolled at the 68 NARHY, Lagos reflects the national ... Background: In Nigeria, adolescents and young people (AYP) aged 10 - 24, comprise 22.3% of the population and with HIV prevalence of 3.5%. The AYP living with HIV enrolled at the 68 NARHY, Lagos reflects the national challenges with poor viral suppression. The OTZ program aligns with the UNAIDS 95-95-95 goals. It seeks to empower AYPLHIV to be in charge of their treatment and commit to triple zero outcomeszero missed appointments, zero missed drugs, and zero viral loads. The purpose of the study was to assess the impact of the OTZ program on viral load suppression among members of the adolescent club in 68 NARHY, Lagos. Method: A cross-sectional retrospective study to evaluate the impact of the OTZ program on the viral load of 53 AYP enrolled in the OTZ program between March 2019 to December 2019 was analyzed. The Percentage of viral load suppression before enrollment compared with 6 and 12 months after enrollment into the OTZ program. The AYP is grouped into 10 - 14, 15 - 19, and 20 - 24 years. Activities conducted were peer driven monthly meetings with the AYP during which the adolescents interacted on issues relating to improving their treatment outcomes, healthcare workers reviewed their clinical status, viral load result, provider peer counseling, and caregivers engagement to support adherence to medication and ARV refills. Results: Before OTZ, 81% aged 10 - 14 years, 75% aged 15 - 19 years, and 25% aged 20 - 24 years were virally suppressed (VL less than 1000 copies/ml). Six months after enrollment, 94% were virally suppressed95% aged 10 - 14 years, 96% aged 15 - 19 years, and 66% aged 20-24 years. Twelve months after enrollment, 96% of AYP were virally suppressed100% aged 10-14 years, 93% aged 15 - 19 years, and 100% aged 20 - 24 years. Males viral load (VL) suppression improved from 79% to 96% and 92%, while females VL suppression improved from 69% to 93% and 100% at 6 and 12 months respectively. Conclusion: The OTZ activities contributed to improved viral load suppression in the AYP of the facility. 展开更多
关键词 Impact Operation triple Zero ADOLESCENT Viral Load NIGERIA
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The Triple Helix of innovation as a double game involving domestic and foreign actors
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作者 Eustache Mêgnigbêto 《Journal of Data and Information Science》 CSCD 2024年第1期82-100,共19页
Purpose:The collaboration relationships between innovation actors at a geographic level may be considered as grouping two separate layers,the domestic and the foreign.At the level of each layer,the relationships and t... Purpose:The collaboration relationships between innovation actors at a geographic level may be considered as grouping two separate layers,the domestic and the foreign.At the level of each layer,the relationships and the actors involved constitute a Triple Helix game.The paper distinguished three levels of analysis:the global grouping together all actors,the domestic grouping together domestic actors,and the foreign related to only actors from partner countries.Design/methodology/approach:Bibliographic records data from the Web of Science for South Korea and West Africa breakdown per innovation actors and distinguishing domestic and international collaboration are analyzed with game theory.The core,the Shapley value,and the nucleolus are computed at the three levels to measure the synergy between actors.Findings:The synergy operates more in South Korea than in West Africa;the government is more present in West Africa than in South Korea;domestic actors create more synergy in South Korea,but foreign more in West Africa;South Korea can consume all the foreign synergy,which is not the case of West Africa.Research limitations:Research data are limited to publication records;techniques and methods used may be extended to other research outputs.Practical implications:West African governments should increase their investment in science,technology,and innovation to benefit more from the synergy their innovation actors contributed at the foreign level.However,the results of the current study may not be sufficient to prove that greater investment will yield benefits from foreign synergies.Originality/value:This paper uses game theory to assess innovation systems by computing the contribution of foreign actors to knowledge production at an area level.It proposes an indicator to this end. 展开更多
关键词 triple Helix Game theory Core Shapley value NUCLEOLUS South Korea West Africa
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Study of plasma parameters of coaxial plasma source using triple Langmuir probe and Faraday cup diagnostics
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作者 Sunil KANCHI Rohit SHUKLA Archana SHARMA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第4期94-100,共7页
Coaxial plasma guns are a type of plasma source that produces plasma which propagates radially and axially controlled by the shape of the ground electrode, which has attracted much interest in several applications. In... Coaxial plasma guns are a type of plasma source that produces plasma which propagates radially and axially controlled by the shape of the ground electrode, which has attracted much interest in several applications. In this work, a 120° opening angle of CPG nozzle is used as a plasma gun configuration that operates at the energy of 150 J. The ionization of polyethylene insulator between the electrodes of the gun produces a cloud of hydrogen and carbon plasma.The triple Langmuir probe and Faraday cup are used to measure plasma density and plasma temperature. These methods are used to measure the on-axis and off-axis plasma divergence of the coaxial plasma gun. The peak values of ion densities measured at a distance of 25 mm on-axis from the plasma gun are(1.6±0.5)×10^(19)m^(-3)and(2.8±0.6)×10^(19)m^(-3)for hydrogen and carbon plasma respectively and the peak temperature is 3.02±0.5 eV. The mean propagation velocity of plasma is calculated using the transit times of plasma at different distances from the plasma gun and is found to be 4.54±0.25 cm/μs and 1.81±0.18 cm/μs for hydrogen and carbon plasma respectively. The Debye radius is obtained from the measured experimental data that satisfies the thin sheath approximation. The shot-to-shot stability of plasma parameters facilitates the use of plasma guns in laboratory experiments. These types of plasma sources can be used in many applications like plasma opening switches, plasma devices, and as plasma sources. 展开更多
关键词 coaxial plasma source triple Langmuir probe Faraday cup plasma density plasma temperature
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Enhancing Relational Triple Extraction in Specific Domains:Semantic Enhancement and Synergy of Large Language Models and Small Pre-Trained Language Models
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作者 Jiakai Li Jianpeng Hu Geng Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第5期2481-2503,共23页
In the process of constructing domain-specific knowledge graphs,the task of relational triple extraction plays a critical role in transforming unstructured text into structured information.Existing relational triple e... In the process of constructing domain-specific knowledge graphs,the task of relational triple extraction plays a critical role in transforming unstructured text into structured information.Existing relational triple extraction models facemultiple challenges when processing domain-specific data,including insufficient utilization of semantic interaction information between entities and relations,difficulties in handling challenging samples,and the scarcity of domain-specific datasets.To address these issues,our study introduces three innovative components:Relation semantic enhancement,data augmentation,and a voting strategy,all designed to significantly improve the model’s performance in tackling domain-specific relational triple extraction tasks.We first propose an innovative attention interaction module.This method significantly enhances the semantic interaction capabilities between entities and relations by integrating semantic information fromrelation labels.Second,we propose a voting strategy that effectively combines the strengths of large languagemodels(LLMs)and fine-tuned small pre-trained language models(SLMs)to reevaluate challenging samples,thereby improving the model’s adaptability in specific domains.Additionally,we explore the use of LLMs for data augmentation,aiming to generate domain-specific datasets to alleviate the scarcity of domain data.Experiments conducted on three domain-specific datasets demonstrate that our model outperforms existing comparative models in several aspects,with F1 scores exceeding the State of the Art models by 2%,1.6%,and 0.6%,respectively,validating the effectiveness and generalizability of our approach. 展开更多
关键词 Relational triple extraction semantic interaction large language models data augmentation specific domains
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Upper and Lower Bounds of the α-Universal Triple I Method for Unified Interval Implications
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作者 Yiming Tang Jianwei Gao Yifan Huang 《Computers, Materials & Continua》 SCIE EI 2024年第4期1063-1088,共26页
Theα-universal triple I(α-UTI)method is a recognized scheme in the field of fuzzy reasoning,whichwas proposed by our research group previously.The robustness of fuzzy reasoning determines the quality of reasoning al... Theα-universal triple I(α-UTI)method is a recognized scheme in the field of fuzzy reasoning,whichwas proposed by our research group previously.The robustness of fuzzy reasoning determines the quality of reasoning algorithms to a large extent,which is quantified by calculating the disparity between the output of fuzzy reasoning with interference and the output without interference.Therefore,in this study,the interval robustness(embodied as the interval stability)of theα-UTI method is explored in the interval-valued fuzzy environment.To begin with,the stability of theα-UTI method is explored for the case of an individual rule,and the upper and lower bounds of its results are estimated,using four kinds of unified interval implications(including the R-interval implication,the S-interval implication,the QL-interval implication and the interval t-norm implication).Through analysis,it is found that theα-UTI method exhibits good interval stability for an individual rule.Moreover,the stability of theα-UTI method is revealed in the case of multiple rules,and the upper and lower bounds of its outcomes are estimated.The results show that theα-UTI method is stable for multiple rules when four kinds of unified interval implications are used,respectively.Lastly,theα-UTI reasoning chain method is presented,which contains a chain structure with multiple layers.The corresponding solutions and their interval perturbations are investigated.It is found that theα-UTI reasoning chain method is stable in the case of chain reasoning.Two application examples in affective computing are given to verify the stability of theα-UTImethod.In summary,through theoretical proof and example verification,it is found that theα-UTImethod has good interval robustness with four kinds of unified interval implications aiming at the situations of an individual rule,multi-rule and reasoning chain. 展开更多
关键词 Fuzzy reasoning the CRI method the triple I method fuzzy implication interval robustness
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A novel triple periodic minimal surface-like plate lattice and its data-driven optimization method for superior mechanical properties
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作者 Yanda WANG Yanping LIAN +2 位作者 Zhidong WANG Chunpeng WANG Daining FANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第2期217-238,共22页
Lattice structures can be designed to achieve unique mechanical properties and have attracted increasing attention for applications in high-end industrial equipment,along with the advances in additive manufacturing(AM... Lattice structures can be designed to achieve unique mechanical properties and have attracted increasing attention for applications in high-end industrial equipment,along with the advances in additive manufacturing(AM)technologies.In this work,a novel design of plate lattice structures described by a parametric model is proposed to enrich the design space of plate lattice structures with high connectivity suitable for AM processes.The parametric model takes the basic unit of the triple periodic minimal surface(TPMS)lattice as a skeleton and adopts a set of generation parameters to determine the plate lattice structure with different topologies,which takes the advantages of both plate lattices for superior specific mechanical properties and TPMS lattices for high connectivity,and therefore is referred to as a TPMS-like plate lattice(TLPL).Furthermore,a data-driven shape optimization method is proposed to optimize the TLPL structure for maximum mechanical properties with or without the isotropic constraints.In this method,the genetic algorithm for the optimization is utilized for global search capability,and an artificial neural network(ANN)model for individual fitness estimation is integrated for high efficiency.A set of optimized TLPLs at different relative densities are experimentally validated by the selective laser melting(SLM)fabricated samples.It is confirmed that the optimized TLPLs could achieve elastic isotropy and have superior stiffness over other isotropic lattice structures. 展开更多
关键词 lattice structure triple periodic minimal surface(TPMS) plate lattice structural optimization machine learning
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Hilbert C~*-模和JB~*-Triples
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作者 许天周 高英敏 《青海师范大学学报(自然科学版)》 1993年第4期22-28,共7页
研究了HilbertC*-模和JB*-tripes的关系,我们证明了:(1)C*-代数上的每个Hilbert模等距同构于算子JB*-triple;(2)交换JB*-triple必定是某一C*-代数上HilbertC*-模。
关键词 JB*-triple HILBERT C*-模 C*-代数 算子JB*-triple
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JB~*—triples的交换性与JB~*—triple幂零元
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作者 许天周 柳絮 《青海师范大学学报(自然科学版)》 1993年第2期20-24,共5页
本文部分地证明了文[1]提出的猜想是正确的,说明 Kaplansky 定理在 JB~*-triple 意义下成立,它是有关结果的推广。
关键词 JB-triple 交换性 JB-triple 幂零元
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交换JB-triples
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作者 许天周 《青海师范大学学报(自然科学版)》 1991年第1期13-18,共6页
本文系统地讨论了交换JB*-■riples的一些问题,最后给出一个猜想。
关键词 JB^*-triples Gelfand表示 理想
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图形化本体模型到N-TRIPLES文本转化方法研究
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作者 唐淳 万佳 +1 位作者 唐胜群 屈振新 《计算机应用与软件》 CSCD 2010年第12期167-169,共3页
分析了图形化本体编辑器VOEDITROR中的OWL构造子分类方法,提出了将图形化本体模型转化为N-TRIPLES格式文本的算法,解决了可视化本体建模工具与Oracle11g之间的整合问题。目前这套算法已经应用于以VOEDTIOR、VOQUERY和Ora-cle11g为核心... 分析了图形化本体编辑器VOEDITROR中的OWL构造子分类方法,提出了将图形化本体模型转化为N-TRIPLES格式文本的算法,解决了可视化本体建模工具与Oracle11g之间的整合问题。目前这套算法已经应用于以VOEDTIOR、VOQUERY和Ora-cle11g为核心的基于语义Web技术的网上资源整合平台中。 展开更多
关键词 本体 本体模型 VOEDITOR N-triples Oracle11g
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基于UFLC-Triple TOF-MS/MS的活心丸全成分分析 被引量:4
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作者 郑苏楠 刘玉铃 +1 位作者 吴灏 王永刚 《中南药学》 CAS 2023年第4期924-932,共9页
目的应用超快速高效液相色谱串联三重四极杆飞行时间质谱(UFLC-Triple TOF-MS/MS)对中药活心丸的化学成分进行分析。方法以Waters HSS T3(2.1 mm×100 mm,1.8μm)为色谱柱,乙腈-0.1%甲酸为流动相,梯度洗脱,流速0.3 mL·min^(-1)... 目的应用超快速高效液相色谱串联三重四极杆飞行时间质谱(UFLC-Triple TOF-MS/MS)对中药活心丸的化学成分进行分析。方法以Waters HSS T3(2.1 mm×100 mm,1.8μm)为色谱柱,乙腈-0.1%甲酸为流动相,梯度洗脱,流速0.3 mL·min^(-1),采用配有ESI电喷雾源的高分辨三重四极杆飞行时间质谱,分别在正、负离子模式下进样检测。结果通过准确分子量及碎片离子分析、对照品比对、相关文献查阅,共确证和指认出96个化学成分,其中三萜类化合物25个、皂苷类化合物12个、胆汁酸类化合物11个、黄酮类化合物11个、生物碱类化合物10个、蟾毒内酯类化合物12个、有机酸类化合物7个、氨基酸类化合物4个、核苷类化合物1个、甾酮类化合物1个、其他类化合物2个,并解释了代表性成分的裂解规律。结论本研究阐明了活心丸的化学物质基础,为评价其质量及后续药理机制研究提供了科学依据。 展开更多
关键词 中成药 活心丸 化学成分 UFLC-triple TOF-MS/MS
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A novel triple responsive smart fluid for tight oil fracturing-oil expulsion integration 被引量:2
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作者 Ming-Wei Gao Ming-Shan Zhang +5 位作者 Heng-Yi Du Ming-Wei Zhao Cai-Li Dai Qing You Shun Liu Zhe-Hui Jin 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期982-992,共11页
The traditional multi-process to enhance tight oil recovery based on fracturing and huff-n-puff has obvious deficiencies,such as low recovery efficiency,rapid production decline,high cost,and complexity,etc.Therefore,... The traditional multi-process to enhance tight oil recovery based on fracturing and huff-n-puff has obvious deficiencies,such as low recovery efficiency,rapid production decline,high cost,and complexity,etc.Therefore,a new technology,the so-called fracturing-oil expulsion integration,which does not need flowback after fracturing while making full use of the fracturing energy and gel breaking fluids,are needed to enable efficient exploitation of tight oil.A novel triple-responsive smart fluid based on“pseudo-Gemini”zwitterionic viscoelastic surfactant(VES)consisting of N-erucylamidopropyl-N,N-dimethyl-3-ammonio-2-hydroxy-1-propane-sulfonate(EHSB),N,N,N′,N′-tetramethyl-1,3-propanediamine(TMEDA)and sodium p-toluenesulfonate(NaPts),is developed.Then,the rheology of smart fluid is systematically studied at varying conditions(CO_(2),temperature and pressure).Moreover,the mechanism of triple-response is discussed in detail.Finally,a series of fracturing and spontaneous imbibition performances are systematically investigated.The smart fluid shows excellent CO_(2)-,thermal-,and pressure-triple responsive behavior.It can meet the technical requirement of tight oil fracturing construction at 140°C in the presence of 3.5 MPa CO_(2).The gel breaking fluid shows excellent spontaneous imbibition oil expulsion(∼40%),salt resistance(1.2×104 mg/L Na+),temperature resistance(140°C)and aging stability(30 days). 展开更多
关键词 Fracturing-oil expulsion integration Tight oil triple responsive smart fluid "Pseudo-gemini"zwitterionic surfactant Fracturing fluid Spontaneous imbibition
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A Top-down Method of Extraction Entity Relationship Triples and Obtaining Annotated Data
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作者 Zhiqiang Hu Zheng Ma +6 位作者 Jun Shi Zhipeng Li Xun Shao Yangzhao Yang Yong Liao Zhenyuan Gao Jie Zhang 《Journal of Quantum Computing》 2022年第1期13-22,共10页
The extraction of entity relationship triples is very important to build a knowledge graph(KG),meanwhile,various entity relationship extraction algorithms are mostly based on data-driven,especially for the current pop... The extraction of entity relationship triples is very important to build a knowledge graph(KG),meanwhile,various entity relationship extraction algorithms are mostly based on data-driven,especially for the current popular deep learning algorithms.Therefore,obtaining a large number of accurate triples is the key to build a good KG as well as train a good entity relationship extraction algorithm.Because of business requirements,this KG’s application field is determined and the experts’opinions also must be satisfied.Considering these factors we adopt the top-down method which refers to determining the data schema firstly,then filling the specific data according to the schema.The design of data schema is the top-level design of KG,and determining the data schema according to the characteristics of KG is equivalent to determining the scope of data’s collection and the mode of data’s organization.This method is generally suitable for the construction of domain KG.This article proposes a fast and efficient method to extract the topdown type KG’s triples in social media with the help of structured data in the information box on the right side of the related encyclopedia webpage.At the same time,based on the obtained triples,a data labeling method is proposed to obtain sufficiently high-quality training data,using in various Natural Language Processing(NLP)information extraction algorithms’training. 展开更多
关键词 Entity relationship triples knowledge graph TOP-DOWN social media data labeling
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基于Triple-Collocation多源地表温度数据融合方法研究
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作者 周露 宋承运 +1 位作者 王艳丽 孙时雨 《无线电工程》 北大核心 2023年第11期2500-2506,共7页
为充分利用多源地表温度数据,提高区域尺度下地表温度精度,改善地表温度遥感产品的适用性。以淮河流域为研究区,Triple-Collocation(TC)方法为基础,采用最小二乘法,由中分辨率光谱成像仪(MODIS)地表温度与风云三号可见光红外扫描辐射计(... 为充分利用多源地表温度数据,提高区域尺度下地表温度精度,改善地表温度遥感产品的适用性。以淮河流域为研究区,Triple-Collocation(TC)方法为基础,采用最小二乘法,由中分辨率光谱成像仪(MODIS)地表温度与风云三号可见光红外扫描辐射计(FY-3C/VIRR)地表温度遥感产品,结合地面观测站实测数据,研究多源数据融合方法。将淮河流域39个气象站点分为融合站点与验证站点,由融合站点采用反距离插值(IDW)算法得到区域连续地表温度数据,与FY-3C/VIRR地表温度数据、MODIS地表温度数据,融合得到淮河流域地表温度。与地面验证站点对比分析表明,融合后的地表温度,其R^(2)、RMSE和MAE分别为0.98、1.10 K、0.88 K,优于MODIS地表温度的0.92、2.59 K、2.18 K和FY-3C地表温度产品的0.84、6.68 K、5.35 K,精度得到了显著的提高。淮河流域不同月份的温度变化季节性规律明显,且变化主要出现在中部及东部地区,最高温度变化值都达到了20 K以上。 展开更多
关键词 淮河流域 地表温度 数据融合 triple-Collocation
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基于UPLC-Triple-TOF/MS核桃油酚类物质的鉴定与区分
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作者 夏朝盛 侯荣荣 +3 位作者 陆元超 聂小华 余宁翔 孟祥河 《中国粮油学报》 CSCD 北大核心 2023年第7期161-166,共6页
针对机械压榨法(MP)、溶剂萃取法(SE)、水酶法(AEE)等制备的核桃油,本研究测定核桃油的总酚含量(TP)并分析鉴定其酚类化合物;通过酚类物质差异对3种萃取方法的核桃油进行分类、鉴定。研究发现,3种萃取方法制得核桃油TP具有显著差异;SE... 针对机械压榨法(MP)、溶剂萃取法(SE)、水酶法(AEE)等制备的核桃油,本研究测定核桃油的总酚含量(TP)并分析鉴定其酚类化合物;通过酚类物质差异对3种萃取方法的核桃油进行分类、鉴定。研究发现,3种萃取方法制得核桃油TP具有显著差异;SE核桃油TP最高(15.75 mg/kg),AEE核桃油TP次之(11.05 mg/kg),MP核桃油TP最低(9.20 mg/kg);基于HPLC和UPLC-Triple-TOF/MS分析,核桃油共鉴定出15种酚类化合物,且不同核桃油酚类物质类别、丰度与含量差异显著;其中,MP核桃油的酚类化合物种类最丰富。基于代表性酚类化合物的含量及酚类物质类别的相对含量开展主成分分析,能成功区分不同萃取方法的核桃油。 展开更多
关键词 核桃油 酚类化合物 高效液相色谱(HPLC) 超高效液相色谱-三重四级杆飞行时间/质谱联用仪(UPLC-triple-TOF/MS) 主成分分析
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