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Multistage microcellular waterborne polyurethane composite with optionally low-reflection behavior for ultra-efficient electromagnetic interference shielding 被引量:5
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作者 Jianming Yang Hu Wang +4 位作者 Hexin Zhang Peng Lin Hong Gao Youyi Xia Xia Liao 《Journal of Materials Science & Technology》 2025年第5期132-140,共9页
Electromagnetic interference(EMI)shielding materials with superior shielding efficiency and low-reflection properties hold promising potential for utilization across electronic components,precision instruments,and fif... Electromagnetic interference(EMI)shielding materials with superior shielding efficiency and low-reflection properties hold promising potential for utilization across electronic components,precision instruments,and fifth-generation communication equipment.In this study,multistage microcellular waterborne polyurethane(WPU)composites were constructed via gradient induction,layer-by-layer casting,and supercritical carbon dioxide foaming.The gradient-structured WPU/ironcobalt loaded reduced graphene oxide(FeCo@rGO)foam serves as an impedance-matched absorption layer,while the highly conductive WPU/silver loaded glass microspheres(Ag@GM)layer is employed as a reflection layer.Thanks to the incorporation of an asymmetric structure,as well as the introduction of gradient and porous configurations,the composite foam demonstrates excellent conductivity,outstanding EMI SE(74.9 dB),and minimal reflection characteristics(35.28%)in 8.2-12.4 GHz,implying that more than 99.99999%of electromagnetic(EM)waves were blocked and only 35.28%were reflected to the external environment.Interestingly,the reflectivity of the composite foam is reduced to 0.41%at 10.88 GHz due to the resonance for incident and reflected EM waves.Beyond that,the composite foam is characterized by low density(0.47 g/cm^(3))and great stability of EMI shielding properties.This work offers a viable approach for craft-ing lightweight,highly shielding,and minimally reflective EMI shielding composites. 展开更多
关键词 Electromagnetic interference shielding Supercritical carbon dioxide(ScCO_(2))foaming Low reflectivity Multilayered structure MICROCELLULAR
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采用UV-Vis法建立党参中总皂苷及总黄酮含量测定方法 被引量:1
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作者 杨超 薛春龙 +3 位作者 张玺雅 王雅婷 段青青 段秀俊 《广州化工》 2025年第13期56-59,70,共5页
建立党参药材中总皂苷与总黄酮的UV-Vis含量测定方法。总皂苷采用香草醛-浓硫酸显色,总黄酮采用硝酸铝显色,单因素结合正交实验优化显色条件,并通过方法学考察进行验证。得出党参总皂苷的最佳显色条件为浓硫酸加入量0.2 mL、显色温度50... 建立党参药材中总皂苷与总黄酮的UV-Vis含量测定方法。总皂苷采用香草醛-浓硫酸显色,总黄酮采用硝酸铝显色,单因素结合正交实验优化显色条件,并通过方法学考察进行验证。得出党参总皂苷的最佳显色条件为浓硫酸加入量0.2 mL、显色温度50℃,显色时间30 min;总黄酮最佳显色条件为加5%NaNO_(2)溶液2.5 mL、10%Al(NO_(3))_(3)溶液2.5 mL、10%NaOH溶液1 mL,显色温度60℃。在上述显色条件下,党参总皂苷与总黄酮的UV-Vis测定方法满足药典分析方法验证指导原则相关规定。本实验建立的UV-Vis法操作简便,显色稳定,准确度高,重复性好,可用于党参中总皂苷与总黄酮的含量测定。 展开更多
关键词 党参 总皂苷 总黄酮 uv-vis 含量测定
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The Influence of Death Reflection on Existential Well-Being: The Mediating Role of Relational Self-Esteem
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作者 Lei Yue 《心理学研究评论(中英文版)》 2025年第1期1-6,共6页
Global challenges like epidemics,wars,and climate change expose humans to life-and-death threats daily,triggering death anxiety and subsequent death reflection,which involves deliberate cognitive processing of mortali... Global challenges like epidemics,wars,and climate change expose humans to life-and-death threats daily,triggering death anxiety and subsequent death reflection,which involves deliberate cognitive processing of mortality.While some studies have shown the positive impacts of death reflection,such as on well-being,the relationship between death reflection and existential well-being,closely related to life and death,remains unexplored.This study aimed to investigate the effects of death reflection on existential well-being and the mediating role of relational self-esteem.675 university students from Sichuan and Hubei,China,completed the death reflection scale,relational self-esteem scale,and the existential well-being subscale of the spiritual well-being scale.Results indicated that death reflection was positively correlated with both relational self-esteem and existential well-being,and relational self-esteem was positively related to existential well-being.Mediation analysis confirmed that relational self-esteem mediated the relationship between death reflection and existential well-being.This study not only enriches the research content on the positive effects of death reflection theoretically,but also holds significant practical value in guiding individuals who have experienced death or been exposed to death-related information in their psychological reconstruction and recovery. 展开更多
关键词 Death reflection Existential Well-Being Relational Self-esteem
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Abnormal focal length increase of terajet generated in reflection mode
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作者 Yu-Jing Yang Jiang-Tao Qin +2 位作者 De-Long Zhang Sai-Dong Xue Ning Yuan 《Chinese Physics B》 2025年第9期204-209,共6页
We report an interesting and abnormal electromagnetic phenomenon with regard to a terajet(TJ)that is generated in a reflection mode,which is realized by placing a dielectric scatterer onto a metal reflection plate.We ... We report an interesting and abnormal electromagnetic phenomenon with regard to a terajet(TJ)that is generated in a reflection mode,which is realized by placing a dielectric scatterer onto a metal reflection plate.We show that the introduction of an air hollow into metal reflection plate beneath the scatterer does not induce an expected decrease but an abnormal increase of focal length of the TJ by as much as more than three times.This abnormal phenomenon takes place in case that the air hollow is shallow and there exists a critical hollow depth for a given lateral size of air hollow.Larger than the critical depth,the phenomenon no longer occurs.It is explained from viewpoints of both ray optics in terms of role of relative portion of central waves in TJ formation and electromagnetic field theory with regard to hollow-induced phase singularities. 展开更多
关键词 terajet reflection mode air hollow focal length phase singularity
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UV-Vis检测技术在水利工程混凝土减水剂吸附效能定量表征中的应用研究
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作者 田笑 《中文科技期刊数据库(引文版)工程技术》 2025年第12期114-117,共4页
为解决水利工程混凝土中减水剂吸附行为难以快速准确定量的问题,文章采用紫外可见光(UV-Vis)检测技术,构建了基于226nm特征波长的减水剂浓度测试模型,并系统地考察了不同掺合料体系下减水剂吸附率变化规律,采用了标准曲线的构建、吸附... 为解决水利工程混凝土中减水剂吸附行为难以快速准确定量的问题,文章采用紫外可见光(UV-Vis)检测技术,构建了基于226nm特征波长的减水剂浓度测试模型,并系统地考察了不同掺合料体系下减水剂吸附率变化规律,采用了标准曲线的构建、吸附等温试验和混凝土实际配比的验证三个阶段的实验流程,从而实现了从实验室数据到工程现场的完整闭环。实验数据显示,减水剂的吸附率会因掺合料的种类而有明显的变化,其中硅灰体系的吸附率是最高的,高达37.7%。本方法具有操作简单,反应灵敏及工程适应性好的优点,能够为水利工程中混凝土材料设计及外加剂的调控提供准确的技术支撑。 展开更多
关键词 水利工程 减水剂 uv-vis光谱 吸附率定量分析
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Discrete Ultra-Broadband Perfect Anomalous Reflection in Depth Gradient Metasurfaces
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作者 Siyu Gu Cong Wang +5 位作者 Ziying Gao Lei Gao Drolgar Feng Gao Shaojun Wang Yadong Xu 《Chinese Physics Letters》 2025年第9期28-33,共6页
Perfect anomalous reflections have been demonstrated in optical phase gradient metasurfaces(PGMs),but they suffer from single-frequency(narrow-band)response due to the intrinsic limitation of natural geometric periodi... Perfect anomalous reflections have been demonstrated in optical phase gradient metasurfaces(PGMs),but they suffer from single-frequency(narrow-band)response due to the intrinsic limitation of natural geometric periodicity.Here,we provide both numerical and analytical evidence that a depth gradient metasurface can achieve discrete ultra-broadband perfect anomalous reflection in the microwave range in the absence of geometric periodicity.Remarkably,by adjusting the operating frequency of the incident wave,the same effect can be steadily obtained via a physically equivalent phase periodicity in the PGM.Based on this mechanism,a perfect retroreflector with a broadband response ranging from 1 GHz to 40 GHz is realized.Our work has promising applications in communication,source tracking,and military satellites. 展开更多
关键词 phase gradient metasurfaces pgms discrete ultra broadband perfect anomalous reflection depth gradient metasurfaces optical phase gradient metasurfaces geometric periodicity adjusting operating frequency perfect anomalous reflections microwave range
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Analysis of the clinical value of anterior peritoneal reflection for the management of rectal cancer
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作者 Huaqing Zhang Guole Lin +9 位作者 Bin Wu Huizhong Qiu Junyang Lu Xiyu Sun Beizhan Niu Lai Xu Guannan Zhang Zhen Sun Kexuan Li Yi Xiao 《Gastroenterology Report》 2025年第1期251-261,共11页
Background:Tumor location affects rectal cancer management,but no consensus exists on criteria.The anterior peritoneal reflection(aPR),an anatomical landmark,shows potential for defining tumor location but requires cl... Background:Tumor location affects rectal cancer management,but no consensus exists on criteria.The anterior peritoneal reflection(aPR),an anatomical landmark,shows potential for defining tumor location but requires clinical validation.This study evaluated the utility of aPR in guiding neoadjuvant chemoradiotherapy(nCRT)decisions and predicting lateral lymph node(LLN)/distant metastasis patterns.Methods:This single-center retrospective cohort analyzed data from Peking Union Medical College Hospital(Beijing,China)between January 2016 and August 2022.Magnetic resonance imaging(MRI)-measured aPR parameters were pathologically validated.Patients were stratified by aPR-based definition and tumor height(10 cm).Kaplan-Meier survival curves,log-rank tests,and Cox regression were used for prognostic analysis.Results:Among 588 patients(439 tumors≥5 cm from the anal verge),MRI identified aPR with an accuracy of 95.4%.For tumors≥5 cm,aPR-defined middle-to-low rectal cancer showed lower 3-year disease-free survival(DFS)rate than the upper rectal cancer(P=0.010),while their 3-year overall survival(OS)rates were comparable.Conversely,10-cm-defined classification showed no DFS or OS differences(both P>0.2).Cox regression confirmed aPR-defined classification as an independent DFS predictor(HR=3.19,P=0.014),while 10-cm classification was non-predictive.nCRT with tumor regression grade(TRG)0-1 trended toward improved DFS compared with direct surgery(HR=0.56,P=0.072).The independent protective effect of nCRT with TRG 0-1 for DFS was exclusive to the aPR-defined middle-to-low rectal cancer subgroup(HR=0.45,P=0.026)and not observed in the 10-cm subgroup.aPR-defined classification was independently associated with LLNs on MRI and postoperative pulmonary metastasis.Conclusion:aPR may guide nCRT decision-making and predict LLN metastasis and postoperative distant organ metastasis. 展开更多
关键词 rectal neoplasms anterior peritoneal reflection neoadjuvant chemoradiotherapy survival analysis lateral lymph node METASTASES
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On U_(S)-admitting Reflections of T_(0) Spaces
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作者 Liqun LIN Jinbo YANG 《Journal of Mathematical Research with Applications》 2025年第6期800-812,共13页
U_(S)-admitting spaces,which were introduced by Heckmann,enjoy many nice properties similar to those of the extensively studied well-filtered spaces.In this paper,we present a direct construction of the U_(S)-admittin... U_(S)-admitting spaces,which were introduced by Heckmann,enjoy many nice properties similar to those of the extensively studied well-filtered spaces.In this paper,we present a direct construction of the U_(S)-admitting reflections by using U_(S)-admitting determined sets. 展开更多
关键词 well-filtered space reflective subcategory sober space U_(S)-admitting space
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Effect and Reflection of Ideological and Political Teaching Reform in Preliminary Landscape Design Course
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作者 JIA Dehua XIAO Guozeng +1 位作者 XIAO Wenjing WANG Wanxi 《Journal of Landscape Research》 2025年第1期81-84,共4页
Curriculum ideological and political education is an important direction of higher education reform in the new era,aiming to realize the organic integration of professional knowledge imparting and ideological and poli... Curriculum ideological and political education is an important direction of higher education reform in the new era,aiming to realize the organic integration of professional knowledge imparting and ideological and political education.Taking preliminary landscape design course as an example,this paper expounded in detail the implementation of teaching reform from three aspects:the formulation of teaching objectives,the integration of teaching contents and the innovation of teaching methods.This paper systematically summarized the implementation effect of ideological and political education reform,and reflected on the excavation of ideological and political elements,integration degree,innovation of teaching methods,teachers’ideological and political ability and practical teaching.The exploration on curriculum ideological and political teaching provides useful reference and thinking for similar courses,and promotes the sustainable development of curriculum ideological and political education. 展开更多
关键词 Preliminary landscape design Curriculum ideological and political education Teaching effectiveness Teaching reflection Teaching reform
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Experimental Study on the Influence of a Partial Reflection Wall on the Power Performance of a Box-Type Wave Energy Converter
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作者 ZHANG Qi LI Xiao-zhong +3 位作者 LIN Chu-sen JIN Peng YUAN Yu-ming ZHOU Bin-zhen 《China Ocean Engineering》 2025年第4期675-686,共12页
The power generation performance of a heaving body wave energy converter(HBWEC)can be enhanced through strategic deployment in proximity to natural or artificial coastal structures.In this study,coastal structures are... The power generation performance of a heaving body wave energy converter(HBWEC)can be enhanced through strategic deployment in proximity to natural or artificial coastal structures.In this study,coastal structures are represented by a partial reflection wall,enabling the device to harness additional reflected wave energy.However,the mechanisms by which the reflection coefficient and the clearance between the wall and the device affect energy conversion performance remain inadequately understood.This study experimentally investigates these effects.The findings demonstrate that the clearance impact on HBWEC power performance near partial reflection walls aligns with standing wave variation characteristics,with optimal positioning near the second antinode of the HBWEC's heaving natural period.Enhanced reflection coefficients improve energy conversion efficiency within the wave spectrum around the device's heaving natural period.Additionally,significant water sloshing observed within the clearance may diminish power performance,as verified through computational fluid dynamics(CFD)analysis.This phenomenon results from the multiplicative relationship of leeside clearance with 0.5λ(λis the wavelength).These insights suggest that practical engineering implementation requires balanced consideration of reflection coefficient,clearance,sloshing phenomenon,and heaving restriction system,rather than individual parameter optimization. 展开更多
关键词 heaving body wave energy converter partial reflection wall power performance heaving restriction system sloshing phenomenon
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Metacognition Inspired Reflective Chain-of-Thought for Knowledge-Based VQA
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作者 Zhongfan Sun Kan Guo +1 位作者 Yongli Hu Yong Zhang 《Computers, Materials & Continua》 2026年第4期1909-1933,共25页
Knowledge-based VisualQuestion Answering(VQA)requires the integration of visual information with external knowledge reasoning.Existing approaches typically retrieve information from external corpora and rely on pretra... Knowledge-based VisualQuestion Answering(VQA)requires the integration of visual information with external knowledge reasoning.Existing approaches typically retrieve information from external corpora and rely on pretrained language models for reasoning.However,their performance is often hindered by the limited capabilities of retrievers and the constrained size of knowledge bases.Moreover,relying on image captions to bridge the modal gap between visual and language modalities can lead to the omission of critical visual details.To address these limitations,we propose the Reflective Chain-of-Thought(ReCoT)method,a simple yet effective framework inspired by metacognition theory.ReCoT effectively activates the reasoning capabilities ofMultimodal Large LanguageModels(MLLMs),providing essential visual and knowledge cues required to solve complex visual questions.It simulates a metacognitive reasoning process that encompasses monitoring,reflection,and correction.Specifically,in the initial generation stage,an MLLM produces a preliminary answer that serves as the model’s initial cognitive output.During the reflective reasoning stage,this answer is critically examined to generate a reflective rationale that integrates key visual evidence and relevant knowledge.In the final refinement stage,a smaller language model leverages this rationale to revise the initial prediction,resulting in amore accurate final answer.By harnessing the strengths ofMLLMs in visual and knowledge grounding,ReCoT enables smaller language models to reason effectively without dependence on image captions or external knowledge bases.Experimental results demonstrate that ReCoT achieves substantial performance improvements,outperforming state-of-the-art methods by 2.26%on OK-VQA and 5.8%on A-OKVQA. 展开更多
关键词 Knowledge-based VQA METACOGNITION reflective chain-of-thought answer refinement
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A conceptual analysis of reflective supervision for creating a positive intensive care practice environment
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作者 Mpho Grace Chipu 《International Journal of Nursing Sciences》 2026年第1期88-95,共8页
Objectives This study aimed to explore and clarify the concept of reflective supervision as a professional self-care strategy to create a positive Intensive Care Unit(ICU)practice environment.Methods Walker and Avant... Objectives This study aimed to explore and clarify the concept of reflective supervision as a professional self-care strategy to create a positive Intensive Care Unit(ICU)practice environment.Methods Walker and Avant’s eight-step concept analysis approach was utilized to identify and define the attributes,antecedents,and consequences of reflective supervision in the ICU.An extensive literature search was conducted across various databases,including Google Scholar,CINAHL,PubMed.Articles published from 2005 to 2025 were identified.We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)2020 statement to indicate the included articles and extract related data based on relevance.Results Forty articles were included in the analysis.The identified attributes included the supervisor-supervisee relationship,effective communication,teamwork,collaborations,reflection,competencies,feedback,continuous support,and autonomous choice.The identified antecedents included participation,supportive supervision,flexibility,open-door policy,training,and motivation.Consequences impacting the success of reflective supervision were identified as promotion of resiliency,autonomy,work-life balance,self-awareness,increased self-esteem,professional development,critical thinking,increased job satisfaction,and enhanced commitment.Conclusions Reflective supervision is a complex professional self-care strategy that enhances ICU practice,by promoting nurses’well-being,self-awareness,therapeutic skills,and professional development. 展开更多
关键词 Concept analysis Intensive Care Unit NURSING Positive environment reflective supervision
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Quantifying the impact of dust retention on maize canopy spectral reflectance and vegetation indices in dust belt regions:A case study in southern Xinjiang,China
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作者 MA Baodong GAO Shuxian +2 位作者 KANG Ting CHE Defu SHU Yang 《Journal of Arid Land》 2026年第1期101-130,共30页
Sand dust belts span approximately one-fifth of the global land surface.In these regions,dust tends to settle on vegetation surfaces,altering the observed reflectance and affecting remote sensing detections.To enhance... Sand dust belts span approximately one-fifth of the global land surface.In these regions,dust tends to settle on vegetation surfaces,altering the observed reflectance and affecting remote sensing detections.To enhance the accuracy of maize growth monitoring in dust-affected regions,this study aims to quantify the effect of sand dust retention on maize during the tasseling stage in the Kashgar Prefecture,Xinjiang Uygur Autonomous Region,China,by analyzing changes in canopy reflectance and vegetation indices.First,field sampling was conducted to measure the key canopy structure parameters and dust retention levels of maize,and laboratory spectral measurements were performed on leaf spectral properties under gradient dust retention.The measured data were then used to drive the LargE-Scale remote sensing data and image Simulation framework(LESS)model for simulating realistic maize canopy spectra across different dust levels,with validation against Sentinel-2 imagery.Second,on the basis of the simulated and satellite-derived spectra,the dust resistance of 36 common vegetation indices was systematically evaluated,and new robust dust-resistant indices were developed.The results showed that compared with dust-free maize,the canopy reflectance of dust-retained maize followed an increase–decrease–increase pattern,with critical turning points at 735 and 1325 nm.The maximum reflectance difference of–0.11755(change rate:29.002%)occurred within the 735–1325 nm range at 24 g/m^(2)dust retention,and the minimum reflectance difference of 0.04285(change rate:148.950%)was observed in the 350–735 nm range under the same dust retention level.Among the 36 vegetation indices,only the global environment monitoring index(GEMI)and the ratio of transformed chlorophyll absorption in reflectance index to optimized soil-adjusted vegetation index(TCARI/OSAVI)exhibited dust resistance,with GEMI being effective below 6 g/m^(2)and TCARI/OSAVI remaining stable across all levels(average ratio:0.970).The newly developed indices in this study,(RE3–RE2)/(NIR–RE2),(RE3–RE2)/(RE4–RE2),and(NIR–RE2)/(RE4–RE2),retained values within the predefined dust-resistant range over the full dust retention levels of 0–24 g/m^(2),thus showing a more stable dust resistance compared with the commonly used 36 vegetation indices.Specially,(RE3–RE2)/(RE4–RE2)performed the most robustly in Sentinel-2 imagery,that is,58.020%of pixels were within the dust-resistant range,and an average ratio of 0.937 was obtained for the original-spectra index.This study provides a scientific basis for crop monitoring and management in dust-affected regions. 展开更多
关键词 sand dust retention canopy spectral reflectance LargE-Scale remote sensing data and image Simulation framework(LESS)model dust-resistant vegetation indices tasseling-stage maize Sentinel-2 imagery
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红花龙胆不同药用部位UV-Vis和UPLC指纹图谱研究及资源评价 被引量:16
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作者 沈涛 张霁 +2 位作者 赵艳丽 左智天 王元忠 《中草药》 CAS CSCD 北大核心 2016年第2期309-317,共9页
目的建立红花龙胆Gentiana rhodantha不同药用部位UV-Vis和UPLC指纹图谱,结合多变量分析研究红花龙胆根、茎、叶和花中化学成分的整体分布与质量分数变化。方法 Shim-pack XR-ODS III液相色谱柱(150 mm×2.0 mm,2.2μm)。流动相为... 目的建立红花龙胆Gentiana rhodantha不同药用部位UV-Vis和UPLC指纹图谱,结合多变量分析研究红花龙胆根、茎、叶和花中化学成分的整体分布与质量分数变化。方法 Shim-pack XR-ODS III液相色谱柱(150 mm×2.0 mm,2.2μm)。流动相为0.1%甲酸水溶液和乙腈,梯度洗脱,柱温40℃;检测波长242 nm,进样量0.3μL;体积流量为1.00 mL/min。电喷雾离子源(ESI)正/负离子模式,多反应监测(MRM)模式,喷雾电压3.5 k V,脱溶剂管温度250℃,鞘气和干燥气体积流量分别为3.0 L/min和15.0 L/min,碰撞气体积流量0.15 mL/min;UV-Vis指纹图谱测定,检测波长200-500 nm,狭缝1.0 nm,采样间隔0.5 nm;采用偏最小二乘判别分析(PLS-DA),变量投影重要性准则(VIP)和系统聚类(CA)对不同产地药材进行分类研究。结果 UPLC和UV-Vis方法学考察显示,精密度、稳定性、重复性试验RSD均小于2.00%;马钱苷酸、芒果苷和当药苷加样回收率在97.89%-102.71%,RSD在1.09%-2.88%;11点平滑+一阶导数预处理为最佳光谱预处理方法,PLS-DA模型R2cal=0.9315,RMSEE=0.302,R2val=0.901,RMSEP=0.341,根、茎、叶和花UV-Vis光谱呈现指纹特性;UPLC指纹图谱相似度分析显示植株化学成分分别在叶部和花部较接近,根部和茎部较相似。不同产地红花龙胆根部UPLC指纹图相似性系数变化范围大,药材质量不稳定。马钱苷酸、芒果苷在叶片和花中量较高[(1.46±0.42)、(51.59±15.45)mg/g];当药苷在根中量较高[(4.41±3.24)mg/g]。叶片总体呈现较高的化学成分量,马钱苷酸、芒果苷和当药苷量对不同药用部位的区分均有较大贡献。聚类分析显示,不同产地红花龙胆植株化学成分呈现一定地理特征,高海拔地区的药材和低海拔地区的药材成分整体差别较大,聚为不同类群。结论 UPLC和UV-Vis指纹图谱相结合可反映红花龙胆根、茎、叶和花中化学成分的整体分布与质量分数变化,研究结果为野生红花龙胆资源的质量评价提供方法和理论依据。 展开更多
关键词 红花龙胆 UPLC指纹图谱 uv-vis指纹图谱 多变量分析 资源评价
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羽流UV-VIS辐射在液体火箭发动机故障诊断中的应用技术研究 被引量:12
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作者 赵永学 张育林 +1 位作者 李麦亮 周进 《宇航学报》 EI CAS CSCD 北大核心 2002年第1期34-39,共6页
为发展基于羽流 UV - VIS辐射光谱的液体火箭发动机故障诊断技术 ,以光谱采集系统为测量手段 ,对三组元模型发动机排气羽流及用以模拟煤油 -氧发动机燃烧的气氧 -煤油火焰的近紫外与可见光谱辐射进行了实验研究 ,利用辐射传递模型对实... 为发展基于羽流 UV - VIS辐射光谱的液体火箭发动机故障诊断技术 ,以光谱采集系统为测量手段 ,对三组元模型发动机排气羽流及用以模拟煤油 -氧发动机燃烧的气氧 -煤油火焰的近紫外与可见光谱辐射进行了实验研究 ,利用辐射传递模型对实验结果进行了理论计算 ,利用演化算法对实验结果进行了反算。 展开更多
关键词 液体火箭发动机 故障诊断 羽流 辐射光谱检测 uv-vis
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Fracture identification based on remote detection acoustic reflection logging 被引量:10
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作者 张宫 李宁 +2 位作者 郭宏伟 武宏亮 罗超 《Applied Geophysics》 SCIE CSCD 2015年第4期473-481,626,共10页
Fracture identification is important for the evaluation of carbonate reservoirs. However, conventional logging equipment has small depth of investigation and cannot detect rock fractures more than three meters away fr... Fracture identification is important for the evaluation of carbonate reservoirs. However, conventional logging equipment has small depth of investigation and cannot detect rock fractures more than three meters away from the borehole. Remote acoustic logging uses phase-controlled array-transmitting and long sound probes that increase the depth of investigation. The interpretation of logging data with respect to fractures is typically guided by practical experience rather than theory and is often ambiguous. We use remote acoustic reflection logging data and high-order finite-difference approximations in the forward modeling and prestack reverse-time migration to image fractures. First, we perform forward modeling of the fracture responses as a function of the fracture-borehole wall distance, aperture, and dip angle. Second, we extract the energy intensity within the imaging area to determine whether the fracture can be identified as the formation velocity is varied. Finally, we evaluate the effect of the fracture-borehole distance, fracture aperture, and dip angle on fracture identification. 展开更多
关键词 remote detection acoustic wave reverse-time migration finite difference wave iequation reflection wave imaging i
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Reflection coefficients of P-SV waves in weak anisotropic media 被引量:4
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作者 刘前坤 韩立国 +1 位作者 王恩利 单刚义 《Applied Geophysics》 SCIE CSCD 2008年第1期18-23,共6页
We introduce the Thomsen anisotropic parameters into the approximate linear reflection coefficient equation for P-SV wave in weakly anisotropic HTI media. From this we get a new, more effective, and practical reflecti... We introduce the Thomsen anisotropic parameters into the approximate linear reflection coefficient equation for P-SV wave in weakly anisotropic HTI media. From this we get a new, more effective, and practical reflection coefficient equation. We performed forward modeling to AVO attributes, obtaining excellent results. The combined AVO attribute analysis of PP and PS reflection data can greatly reduce ambiguity, obtain better petrophysical parameters, and improve parameter accuracy. 展开更多
关键词 Weak anisotropy P-SV wave reflection coefficient.
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樟脑磺酸掺杂聚苯胺在不同有机溶剂中的UV-Vis光谱 被引量:5
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作者 於黄中 黄河 +2 位作者 熊予莹 刘少琼 任兵 《光谱实验室》 CAS CSCD 2002年第3期290-292,共3页
由于不同的有机溶剂与樟脑磺酸掺杂的聚苯胺 (PANI.HCSA)有不同的作用 ,故 PANI.HCSA在不同的有机溶剂中有不同的紫外 -可见光谱。本文研究了 PANI.HCSA在有机溶剂间甲酚 (m- cresol)、二甲基亚砜 (DMSO)、N,N-二甲酰胺 (DMF)、N-甲基 -... 由于不同的有机溶剂与樟脑磺酸掺杂的聚苯胺 (PANI.HCSA)有不同的作用 ,故 PANI.HCSA在不同的有机溶剂中有不同的紫外 -可见光谱。本文研究了 PANI.HCSA在有机溶剂间甲酚 (m- cresol)、二甲基亚砜 (DMSO)、N,N-二甲酰胺 (DMF)、N-甲基 - 2 -吡咯烷酮 (NMP)中的 UV- Vis光谱的不同及其变化 。 展开更多
关键词 樟脑磺酸 掺杂 聚苯胺 有机溶剂 uv-vis光谱 导电聚合物
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