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喙尾琵琶甲化学成分的研究

中草药 2025年第4期56卷 1130-1137页

作者：张兴平周轶平缪晶茜李碧桃文政琦王扣昆明医科大学药学院暨云南省天然药物药理重点实验室云南省现代生物医药产业学院昆明医科大学第一附属医院肿瘤科

目的研究喙尾琵琶甲Blaps rhynchoptera的化学成分及其细胞毒活性。方法采用硅胶、Sephadex LH-20凝胶、MCI柱色谱，以及制备高效液相色谱等技术进行化合物的分离纯化，通过理化性质及波谱学方法鉴定结构，运用MTT法评价化合物的细胞... 详细信息

目的研究喙尾琵琶甲Blaps rhynchoptera的化学成分及其细胞毒活性。方法采用硅胶、Sephadex LH-20凝胶、MCI柱色谱，以及制备高效液相色谱等技术进行化合物的分离纯化，通过理化性质及波谱学方法鉴定结构，运用MTT法评价化合物的细胞毒活性。结果从喙尾琵琶甲虫体的95%乙醇提取物中分离得到了21个化合物，分别鉴定为（3R）-6-羟基-3-甲基-3, 8-二乙基-2-吲哚酮（1）、blapindole I（2）、blapindole K（3）、尿嘧啶（4）、胸腺嘧啶（5）、胸腺嘧啶脱氧核苷（6）、对羟基苯甲酸（7）、对羟基苯乙酸（8）、对苯二酚（9）、2-甲基对苯二酚（10）、2-乙基对苯二酚（11）、原儿茶酸（12）、羟基酪醇（13）、香草醇（14）、原儿茶醛（15）、N-乙酰基多巴胺（16）、对羟基苯丙酸甲酯（17）、苯乙酸（18）、1-H-吲哚-3-羧酸（19）、12-羟基硬脂酸（20）和乌金苷（21）。化合物1、10和11对人白血病K562细胞的半数抑制浓度（median inhibition concentration,IC50）值分别为7.95、3.23和4.13μmol/L；化合物10对人结肠癌HCT116细胞的IC50值为19.11μmol/L。结论化合物1为新的吲哚酮类化合物，命名为琵琶甲酮A。化合物4、5、8、14、17、18、20、21为首次从琵琶甲属中分离得到。9个化合物对K562细胞表现出抑制活性，其中化合物1、10和11显著强于顺铂(IC50=40.90μmol/L)。化合物10对HCT116细胞具有抑制作用，与顺铂作用相当(IC50=19.80μmol/L)。

关键词：喙尾琵琶甲吲哚酮类琵琶甲酮A 2-甲基对苯二酚 2-乙基对苯二酚细胞毒活性

Polymer Supported Synthesis of Multi-substituted Pyrimidine-4-one Derivatives via Pbf-activated Thiourea

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Chemical Research in Chinese Universities 2011年第2期27卷 221-223页

作者： LI Jl-zhen kou jing-ping MI Yu-hua College of Chemistry Jilin University Changchun 130021 P. R. China

Efficient polymer supported synthesis of multi-substituted pyrimidine-4-one derivatives was described. Target products were produced from fluorenylmethoxycarbonyl（Fmoc） protected β-amino acid loaded on hydro- xymethyl resin through deprotection, N-alkylation, guanidine formation, and cleavage of 2,2,4,6,7-pentamethyl dihy-drobenzofuran-sulfonyl（Pbf） by trifluoracetic acid（TFA） followed with cyclization. The procedure has the advantages of easy operation, mild reaction conditions, and forming multiple substituents.

关键词： Guanidine Polymer supported synthesis Pyrimidine Amino acid Thiourea

Soldering of Zr-based bulk metallic glass and copper by Au-12Ge eutectic alloy

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Rare Metals 2019年第1期38卷 52-58页

作者： Jun Wang jing Cui Hong-Chao kou Heng Guan Jin-Shan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Zr-based bulk metallic glass and copper with different surface roughness were soldered using low temperature eutectic Au-12 Ge(wt%) solder on a thermomechanical simulator. The cross-sectional microstructures of the brazed joints were analyzed by scanning electron microscopy(SEM) and transmission electron microscope(TEM) in detail, and the compositional distribution along the interface was analyzed by energy-dispersive spectrometer(EDS). Results show that the surface roughness of base metals plays an important role in the quality of the brazed joint because the surface roughness can enlarge the effective contact area, which can improve the brazing surface quality between two materials. A moderate roughness of treated Zr-based metallic glass of 18 μm is shown to be the best for the soldering, while the surface roughness has a weak effect on the soldering behavior of Au-12 Ge solder on copper. After soldering, long-range diffusion of atoms occurs between the base metal and solder, and five distinct regions are formed at the joint region.

关键词： Bulk metallic glass Soldering Au-Ge eutectic alloy Interface

Bogoliubov excitations in a Bose–Hubbard model on a hyperhoneycomb lattice

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Chinese Physics B 2018年第5期27卷 108-114页

作者： wen-yan Zhou Ya-jie Wu Su-Peng kou Department of Physics Beijing Normal UniversityBeijing 100875China School of Science Xi'an Technological UniversityXi'an 710032China

We study the topological properties of Bogoliubov excitation modes in a Bose–Hubbard model of three-dimensional(3 D)hyperhoneycomb *** the non-interacting case,there exist nodal loop excitations in the Bloch *** the on-site repulsive interaction increases,the system is first driven into the superfluid phase and then into the Mott-insulator *** both phases,the excitation bands exhibit robust nodal-loop structures and bosonic surface *** a topology point of view,these nodal-loop excitation modes may be viewed as a permanent fingerprint left in the Bloch bands.

关键词： hyperhoneycomb lattice Mott-superfluid transition Bogoliubov excitations nodal-loop

Landslide Displacement Prediction Based on Time Series and PSO-BP Model in Three Georges Reservoir, China

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Journal of Earth Science 2024年第3期35卷 1079-1082页

作者： Dexiang Gao kou Li Yuncheng Cai Tao wen School of Geosciences Yangtze UniversityWuhan 430100China School of Science Yunnan Agricultural UniversityKunming 650201China

0 INTRODUCTION Landslides are one of the most frequent geological disasters in the world(wen et al.,2020;Froude and Petley,2018),which have occurred frequently and widely distributed in China for a long *** landslides are essentially a complex multidimensional nonlinear dynamic system affected by its own geological conditions and external factors(Ma et al.,2021;Wang et al.,2019),including geotechnical characteristics,hydrogeology,geomorphologic conditions,climate,and weathering(Ma et al.,2020).The interaction of these factors makes the change of landslide displacement random,fuzzy and variable(Park and Michalowski,2017),and also brings great difficulties to the landslide displacement prediction(Ma et al.,2018).

关键词： landslide Landslide weathering

Partial organic substitution weakens the negative effect of chemical fertilizer on soil micro-food webs

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Journal of Integrative Agriculture 2022年第10期21卷 3037-3050页

作者： LIU Han-wen ZHANG Xiao-ke ZHANG Gui-zong kou Xin-chang LIANG wen-ju Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China School of Geographical Science Northeast Normal UniversityChangchun 130024P.R.China

Soil biotic communities play vital roles in enhancing soil nutrient cycling and soil ***-term excessive nitrogen(N)application is disadvantageous to the stability of soil food webs and affects arable soil health and sustainable *** organic substitution is essential to improve soil health and alleviate the disadvantages of excessive chemical ***,the biological effects of various organic amendments on soil micro-food webs are poorly *** order to explore the effects of various organic amendments including stover,biochar and manure on soil micro-food webs(microbial and nematode communities),a field plot experiment with maize having five treatments viz.,100%urea(100%N),70%urea(70%N),70%urea plus stover(Stover),70%urea plus cattle manure(Manure)and 70%urea plus biochar(Biochar)was *** treatment increased the carbon(C)to N use efficiency of soil microbes,which contributed to the retention of soil C,while Biochar treatment elevated soil organic C(SOC)and soil p ***,Biochar treatment mitigated the negative effects of soil acidification on the soil micro-food web and reduced the abundance of plant ***,the biological effect of organic amendments was distinguished from chemical fertilization(100%N and 70%N)through principal co-ordinates *** relationships among soil properties,microbial and nematode biomass in the 100%N treatment were diminished in treatments where chemical fertilizer was *** bottom-up effects on soil food webs were observed in organic substitution *** conclusion,organic amendments improved soil fertility by regulating soil microbial and nematode communities in the cropland ecosystem,alleviated the negative effects of chemical fertilizer on the micro-food webs and controlled the trophic cascades among soil biota.

关键词： microbial community nematode community soil micro-food webs organic substitution chemical fertilizer soil health

原子吸收光谱法测定矿石中Au的分析技术及最优化模型研究

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光谱学与光谱分析 2025年第2期45卷 426-433页

作者：王鹏门倩妮甘黎明白金峰王啸井斌强寇少磊刘慧蓝何涛刘玖芬中国地质调查局西安矿产资源调查中心陕西西安710100 中国地质调查局金矿勘查技术创新中心陕西西安710100 中国地质调查局自然资源综合调查指挥中心北京100055 中国地质科学院地球物理地球化学勘查研究所河北廊坊065000 中国矿业报社北京100037 中国地质大学(北京) 北京100083

矿石中Au通常以颗粒金或者晶格金的形式存在,在不同类型的金矿石中赋存状态不同,其特殊的延展性引起的颗粒效应对于Au样品的分析技术带来挑战,并且其制备流程要素繁多且不易控制,直接影响Au分析的准确性和稳定性。以矿石中金元素为研究... 详细信息

矿石中Au通常以颗粒金或者晶格金的形式存在,在不同类型的金矿石中赋存状态不同,其特殊的延展性引起的颗粒效应对于Au样品的分析技术带来挑战,并且其制备流程要素繁多且不易控制,直接影响Au分析的准确性和稳定性。以矿石中金元素为研究对象,建立泡塑吸附-原子吸收光谱法测定矿石中Au的分析方法,针对样品测试流程中的关键要素进行定性判断和定量计算,提出基于灰色关联度-响应曲面法的最优化模型。讨论样品分析技术中焙烧、消解、富集和解脱等重要环节,确定焙烧方式、消解酸度、富集时间和硫脲浓度为优化要素,设计正交试验并进行相关性分析,计算灰色关联系数并进行极差确定,定性判断各优化要素的显著性。中心组合设计结合响应曲面法原理制作显著水平表,建立二次多项式回归方程的预测模型并进行显著性分析,绘制三维响应曲面图和二维等高线图对实验数据进行拟合分析,确定最优化模型参数焙烧方式、消解酸度、富集时间和硫脲浓度分别为阶梯式分段焙烧、10.58%、40.00 min、11.65 g·L^(-1)。实验结果表明,在最优化模型条件下对金矿石国家一级标准物质进行制备测试,其方法检出限为0.021,测定下限为0.077,加标回收率为91.6%~104.5%,其正确度和精密度均符合GB/T 20899.2—2019质量控制要求;同时对陕西西秦岭地区和甘肃梅川地区外检样品进行方法验证比对,其相对偏差不超过10%且评价结果均为优秀,表明该检测优化模型方法在实际样品中的应用依然准确可靠,具备正确性和科学性。该研究对于地质矿产实验室快速、准确、简便分析Au元素提出新方法,为检验检测领域中优化多目标参数组合的课题提供了新的思路,同时为新一轮战略找矿行动的准确测试贡献力量。

关键词：金原子吸收光谱法灰色关联度响应曲面法中心组合设计质量控制

Research on expansion joint for high-speed railway long-span bridges in China

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Railway Sciences 2025年第1期4卷 52-81页

作者： Hui Guo Jinzhou Jiang Suoting Hu Chun Yang Qiqi Xiang kou Luo Xinxin Zhao Bing Li Ziquan Yan Liubin Niu Jianye Zhao China Academy of Railway Sciences Corporation Limited Railway Engineering Research InstituteBeijingChina and State Key Laboratory for Track System of High-speed RailwayChina Academy of Railway Sciences Corporation LimitedBeijingChina China Academy of Railway Sciences Corporation Limited Railway Engineering Research InstituteBeijingChina CMCU Engineering Co. Ltd.China National Machinery Industry CorporationChongqingChina First Design Department China Railway Group LtdMajor Bridge Reconnaissance and Design InstituteWuhanChina State Key Laboratory for Track System of High-speed Railway China Academy of Railway Sciences Corporation LimitedBeijingChina and China Academy of Railway Sciences Corporation LimitedRailway Engineering Research InstituteBeijingChina Ma'anshan Yangtze River Bridge Headquarters Ning'an Railway Co.Ltd.China Railway Shanghai GroupMa'anshanChina China Academy of Railway Sciences Corporation Limited Infrastructure Inspection Research InstituteBeijingChina'

Purpose–The bridge expansion joint(BEJ)is a key device for accommodating spatial displacement at the beam end,and for providing vertical support for running trains passing over the gap between the main bridge and the approach *** long-span railway bridges,it must also be coordinated with rail expansion joint(REJ),which is necessary to accommodate the expansion and contraction of,and reducing longitudinal stress in,the *** main aim of this study is to present analysis of recent developments in the research and application of BEJs in high-speed railway(HSR)long-span bridges in China,and to propose a performance-based integral design method for BEJs used with REJs,from both theoretical and engineering ***/methodology/approach–The study first presents a summary on the application and maintenance of BEJs in HSR long-span bridges in China representing an overview of their state of *** of a survey of typical BEJ faults were analyzed,and field testing was conducted on a railway cable-stayed bridge in order to obtain information on the major mechanical characteristics of its BEJ under train *** on the above,a performance-based integral design method for BEJs with maximum expansion range 1600 mm(±800 mm),was proposed,covering all stages from overall conceptual design to consideration of detailed structural design *** performance of the novel BEJ design thus derived was then verified via theoretical analysis under different scenarios,full-scale model testing,and field testing and ***–Two major types of BEJs,deck-type and through-type,are used in HSR long-span bridges in *** BEJ faults were found to mainly include skewness of steel sleepers at the bridge gap,abnormally large longitudinal frictional resistance,and flexural deformation of the scissor *** faults influence BEJ functioning,and thus adversely affect track quality and train running performance at the beam *** to th

关键词： High-speed railway(HSR) Long-span bridge Bridge expansion joint(BEJ) Integral design Rail expansion joint(REJ) Overall stiffness Longitudinal frictional resistance

基于多粒度融合和跨尺度感知的跨模态行人重识别

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通信学报 2025年第1期46卷 108-123页

作者：程德强姬广凯张皓翔江鹤寇旗旗中国矿业大学信息与控制工程学院江苏徐州221116 中国矿业大学计算机科学与技术学院江苏徐州221116

提出一种基于多粒度融合和跨尺度感知的跨模态行人重识别网络,该网络能够有效提取行人图像特征并减少图像间的模态差异。首先,提出多尺度特征融合注意力机制并设计一种多粒度非局部融合框架,有效融合不同模态和不同尺度的图像特征;其次... 详细信息

提出一种基于多粒度融合和跨尺度感知的跨模态行人重识别网络,该网络能够有效提取行人图像特征并减少图像间的模态差异。首先,提出多尺度特征融合注意力机制并设计一种多粒度非局部融合框架,有效融合不同模态和不同尺度的图像特征;其次,提出一种跨尺度特征信息感知策略,该策略可有效降低因视角变化、行人背景变化等产生的无关噪声对行人判别的影响;最后,针对行人图像特征信息不足,设计并行空洞卷积残差模块,获取更为丰富的行人特征信息。将所提方法在2个标准公共数据集与当前先进的跨模态行人重识别方法比较。实验结果表明,所提方法在SYSU-MM01数据集的全搜索模式下的R-1和平均精度(mAP)分别达到75.9%和73.3%,在RegDB数据集的可见光到红外的搜索(VIS to IR)模式下的Rank-1和mAP分别达到93.7%和89.3%,优于所对比的方法,充分证实了所提方法的有效性。

关键词：行人重识别跨模态特征融合跨尺度信息