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不同发育阶段苦瓜皂苷变化特征及相关性分析

南京农业大学学报 2025年第1期48卷 121-132页

作者：林淑婷钟金仙王火珠刘亚婷姜兆华赖正锋吴立东三明市农业科学研究院福建三明365500 三明市农业学校福建三明365500 福建省农业科学院亚热带农业研究所福建漳州363005

[目的]本文旨在探究苦瓜皂苷坐果期间不同发育阶段的变化特征、差异性以及相关性,为苦瓜的功能性育种、最佳采收期确定及品质调控提供科学依据。[方法]以自主选育的苦瓜‘明绿5号'为研究对象,通过香草醛法、高效液相色谱-质谱法、离子... 详细信息

[目的]本文旨在探究苦瓜皂苷坐果期间不同发育阶段的变化特征、差异性以及相关性,为苦瓜的功能性育种、最佳采收期确定及品质调控提供科学依据。[方法]以自主选育的苦瓜‘明绿5号'为研究对象,通过香草醛法、高效液相色谱-质谱法、离子发射光谱仪等测定苦瓜皂苷的组成、含量及其理化因子,并对结果进行化学计量学分析。[结果]不同发育阶段苦瓜总皂苷含量差异极显著(P<0.01),总体呈下降趋势,含量为3.14~10.64 mg·g^(-1),而单果总皂苷含量呈上升趋势,含量为9.03~77.14 mg。特征图谱标定共有峰55个,包含苦瓜皂苷的大部分信息,不同发育阶段共有峰峰面积相对标准偏差(RSD)的变幅为14.68%~193.01%,其中变幅在50%以上的共有峰比例达85.45%。聚类分析与主成分分析结果一致,均将幼果期3个批次聚成一类,膨大期聚为一类,3个成熟期聚为一类。通过偏最小二乘判别分析,苦瓜青熟期至完熟期差异较小,但与幼果期、膨大期差异显著,经质谱验证,最终确定了10个特征差异代谢物。相关性分析表明,在坐果期间,差异代谢物总体与总皂苷、果形指数、氮元素、磷元素和铜元素呈极显著正相关(P<0.01),与果实纵径、果实横径、单果重、果肉厚和含水率呈极显著负相关(P<0.01)。[结论]不同发育阶段苦瓜皂苷组成较稳定,总皂苷及其组分含量有显著性差异。转色期可作为以皂苷收获为目标的最佳采收期。苦瓜皂苷L、苦瓜皂苷K等10个单体皂苷组分是不同发育阶段的主要活性单体,其变化与总皂苷、果形指数以及氮、磷、铜元素密切相关。

关键词：苦瓜皂苷采收期高效液相色谱-质谱相关性

Effects of Rare Earth,Titanium,and Magnesium Additions on Microstructures and Properties of High-boron Medium-carbon Alloy

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Journal of Iron and Steel Research International 2016年第11期23卷 1226-1233页

作者： Xiao-li SHI Ye-hua jiang Rong ZHOU Faculty of Materials Science and Engineering Kunming University of Science and Technology

In order to improve the toughness and wear resistance of high-boron medium-carbon alloy （HBMCA）, a novel wear-resistant HBMCA comprising granular borocarbide was obtained by titanium, magnesium, and rare earth modifications. These modifications gave rise to greatly refined as-cast eutectic borocarbide structures and a less interconnected continuous borocarbide network. Heat treatment mostly produced broken and spheriodized borocarbides that tended to exist as isolated particles in modified HBMCA. The heat treated modified HBMCA exhibited enhanced hardness than pristine and impact toughness was improved significantly to 12.5 J/cm^2. In addition, it displayed 2.39 and 1.7 times greater wear resistance than high-speed steel （HSS） and high nickel-chromium alloy steel （Cr25） at high temperature （500℃）, respectively. Here, the modification mechanisms involving Re2O3, TiN, and MgO/ MgS heterogeneous nuclei were discussed.

关键词： modification eutectic borocarbide spheroidization toughness wear resistance

Running-in Test and Fractal Methodology for Worn Surface Topography Characterization

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Chinese Journal of Mechanical Engineering 2010年第5期23卷 600-605页

作者： JI Cuicui ZHU hua jiang Wei LU Binbin School of Mechanical and Electrical Engineering China University of Mining and Technology Xuzhou 221116 China School of Mechanical Engineering University of Leeds Leeds LS2 9JZ UK

Studying and understanding of the surface topography variation are the basis for analyzing tribological problems,and characterization of worn surface is *** geometry offers a more accurate description for surface roughness that topographic surfaces are statistically self-similar and can be quantitatively evaluated by fractal *** change regularity of worn surface topography is one of the most important aspects of running-in ***,the existing research normally adopts only one friction matching pair to explore the surface topography change,which interrupts the running-in wear process and makes the experimental result lack authenticity and *** this paper,to investigate the change regularity of surface topography during the real running-in process,a series of running-in tests by changing friction pairs under the same operating conditions are conducted on UMT-II Universal Multifunction *** surface profile data are acquired by MiaoXAM2.5X-50X Ultrahigh Precision Surface 3D Profiler and analyzed using fractal dimension D,scale coefficient C and characteristic roughness Ra ＊based on root mean square（RMS） *** characterization effects of the three parameters are discussed and *** results obtained show that there exists remarkable fractal feature of surface topography during running-in process,both D and Ra ＊increase gradually,while C decreases slowly as the wear-in process goes on,and all parameters tend to be stable when the wear process steps into the normal wear *** ＊illustrates higher sensitivity for rough surface characterization compared with the other two *** addition,the running-in test carried with a set of identical surface properties is more scientific and reasonable than the traditional *** proposed research further indicates that the fractal method can quantitatively measure the rough surface,which also provides an evidence for running-in process identification and tribology d

关键词： running-in worn surface topography RMS method fractal dimension scale coefficient characteristic roughness

Polyfluorene based conjugated polymer nanoparticles for two-photon live cell imaging

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Science China Chemistry 2018年第1期61卷 88-96页

作者： Shuang Li Xiao-Fang jiang Qing-hua Xu Institute of Polymer optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and Devices South China University of Technology Guangzhou 510640 China National University of Singapore (Suzhou) Research Institute Suzhou 215123 China Department of Chemistry National University of Singapore Singapore 117543 Singapore

Two-photon excitation microscopy(2 PEM) has been known as a noninvasive and powerful bio-imaging tool for studying living cells, intact tissues and living animals because of their unique advantages such as localized excitation, deep tissue penetration as well as less photo-damage. However, the major limitations that hinder its practical applications in biological systems are low two-photon absorption cross sections of conventional fluorescence probes. Conjugated polymer nanoparticles(CPNs) consisting of highly fluorescent conjugated polymers are promising fluorescent probes for 2 PEM due to their unique advantages including large two-photon absorption cross sections, high fluorescence quantum yield, good photo-stability and biocompatibility, facile chemical synthesis, tunable optical properties as well as versatile surface modifications. This account summarizes the recent efforts of our group on development of novel polyfluorene based CPNs as 2 PEM contrast agents for live cell imaging.

关键词： conjugated polymers nanoparticles two-photon absorption fluorescence microscopy bio-imaging

The DFF-PSP Iterative Separation and Theoretical Bound for PCMA with Long Memory

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Chinese Journal of Electronics 2016年第5期25卷 880-885页

作者： CUI Penghui jiang hua CAO Kai LI Taozhu National Digital Switching Engineering Technological Research Center

This paper proposes the Decision feedbackfeedforward per-survivor processing(DFF-PSP) iterative separation algorithm and the Monte Carlo integrationbased method to compute the theoretical bound for Paired carrier multiple access(PCMA) Single channel blind separation(SCBS) which is highly complex with long memory. The truncated PSP is employed while the pre- and post- cursors are disregarded to control the *** delayed decisions feedforward and local decisions feedback filters are designed to process the pre- and postcursors. The Bit-interleaved code modulation iterative decoder(BICM-ID) is combined with the second soft decision of the truncated PSP to obtain a better *** mixture signal model is regarded as a Multiple-access channel(MAC) with memory, and the theoretical performance bound is obtained via entropy inequality, Monte Carlo integration and Fano inequality. Simulation results show that the DFF-PSP iterative separation provides the good tradeoff between complexity and performance.

关键词： Paired carrier multiple access(PCMA) Single channel blind separation(SCBS) Decision feedbackfeedforward Per-survivor processing Bit-interleaved code modulation iterative decoder(BICM-ID) Multiple-access channel(MAC) Theoretical performance bound

Investigation of Susceptibility to Intergranular Corrosion of Tin-Added Austenitic Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2015年第9期28卷 1183-1189页

作者： Min Sun Yuan-Yuan Yang Ming Luo lai-Zhu jiang Yi-Ming jiang Jin Li Department of Materials Science Fudan University Research and Development Center Baosteel Co. Ltd.

The intergranular corrosion （IGC） character of tin-added B316LX and the influence of tin addition on IGC susceptibility were investigated by DL-EPR, oxalic acid etch test and transmission electron microscopy. IGC susceptibility of B316LX is mainly caused by the precipitation of M23C6 carbide and intermetallic Laves phase. DL-EPR test is unsuitable to evaluate the IGC susceptibility of B316LX with long-time sensitization, because more carbides and inter- metallic phases are formed at grain boundaries and inside the grains, which induce more severe IGC and pits attacks. Tin addition increases the IGC susceptibility, maybe due to diffusion of tin toward grain boundaries.

关键词： Stainless steel Tin SEM TEM Intergranular corrosion

Syntheses, Structures and Magnetic Properties of Two Co(II) Coordination Polymers with 2,5-Pyridine Dicarboxylic Acid

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Chinese Journal of Structural Chemistry 2004年第11期23卷 1230-1237页

作者： XUYing YUANDa-Qiang LINZhen-Zhong WUBen-lai LUOJun-hua HONGMao-Chun StateKeyLaboratoryofStructuralChemistry FujianInstituteofResearchontheStructureofMatterTheChineseAcademyofSciencesFuzhouFujian350002China

The hydro(solvo)thermal reactions of cobalt powder or its chloride with 2,5- pyridine dicarboxylic acid (H2PYDC) yielded two new complexes: [Co(II)2(PYDC)2(H2O)2- (H2O)4]n 1 and {Co(II)[NH2(CH3)2]2(PYDC)2}n 2. It is observed that the reactive solvents result in different connectivity modes of ligand and diverse dimensional extension of crystal structures. The correlation between structure and magnetic property will be discussed in this paper. Crystal data for 1: space group P1, a = 7.0419(17), b = 8.937(2), c = 9.6182(19) ?, α = 91.532(4), β = 99.869(10), γ = 107.889(11)o, V = 565.5(2) ?3, Z = 1, Dc = 1.845 g/cm3, μ = 1.56 mm-1, F(000) = 322 , R = 0.0505 and wR = 0.1580; and those for 2: space group C2/c, a = 14.9075(6), b = 8.2523(3), c = 16.9643(2) ?, β = 100.982(2)o, V = 2048.75(11) ?3, Z = 4, Dc = 1.560 g/cm3, μ = 0.892 mm-1, F(000) = 996, R = 0.0443 and wR = 0.1134.

关键词： hydrothermal solvothermal cobalt magnetic 2 5-pyridine dicarboxylic acid

Cognate Mafic Enclaves Formed by Cumulated Mush Convection in a Granitic Magma Chamber:Evidence from Mineral Chemistry of the Triassic Zhashui Pluton,Qinling Orogen

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Acta Geologica Sinica(English Edition) 2024年第6期98卷 1479-1488页

作者： ZHANG Hongbing ZHOU Xuchen lai Shaocong ZHANG hua QIN jiangfeng State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China

Mafic enclaves in granites are generally considered to represent coeval mafic melts that derived from metasomatized mantle,which can provide valuable information about crust-mantle *** the genetic links between the mafic enclaves and their host monzogranite from the Triassic Zhashui Pluton,Qinling orogenic *** enclaves(220±4.6 Ma)and the monzogranite(220±2.8 Ma)display identical zircon U-Pb ages,and they also share similar trace element and zircon Lu-Hf isotopes,indicating a cognate *** monzogranite displays zirconεHf(t)values of−0.99 to+1.98,while the mafic enclaves show similar values of−0.45 to+3.26;however,differences in mineral chemistry reveal different crystallization *** amphibole from the mafic enclaves has higher temperature and pressure(757℃;2.65 kbar)compared to those of the host monzogranite(733℃;1.96 kbar),suggesting that mafic minerals in the enclaves crystallized at an early ***,apatite in the mafic enclaves displays slightly higher volatile contents(0.72 wt%)than those of the monzogranite(0.66 wt%),indicating a volatile-rich *** results suggest that the mafic enclaves represent early hydrous mafic cumulates in the granitic chamber,and subsequent magma convection would have led to the formation of the mafic enclaves.

关键词： mafic enclaves granitic chamber mafic cumulate convection Qinling or

Morphology and Compatibility of Compatibilized Polyethersulfone and Polycarbonate Blends

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Chemical Research in Chinese Universities 2005年第5期21卷 611-614页

作者： SUN Xiao-bo jiang Dong WU Wei-chun jiang Zhen-hua Research Center for Super Engineering Plastics of Ministry of Education College of Chemistry Jilin University Changchun 130021 P. R. China

A PES-PC （polyethersulfone-polycarbonate） multi block random copolymer was synthesized with two oligomers, polyethersulfone and polycarbonate. The effects of the copolymer, as a compatibilizer, on the morphology and compatibility of the PES-PC blends were investigated. It was found that the addition of this copolymer to the PES-PC blends could improve their compatibility.

关键词： Polyethersulfone Polycarbonate Blend Compatibilizer