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白黄小脆柄菇发酵液中的一个新的血苋烷型倍半萜（英文）

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天然产物研究与开发 2015年第7期27卷 1131-1133页

作者：李学梅尹霞李正辉冯涛刘吉开中国科学院昆明植物研究所植物化学与西部植物资源持续利用国家重点实验室昆明650201 云南农业大学.昆明650201 中国科学院大学北京100049

从白黄小脆柄菇(Psathyrellacandolleana)发酵液提取物的乙酸乙酯层中分离得到一个新的血苋烷型倍半萜(1)和一个已知的没药烷型倍半萜(2)。通过质谱、核磁等方法确定化合物1的结构为15-hydroxy-drimenol。通过文献对照核磁数据确定化合... 详细信息

从白黄小脆柄菇(Psathyrellacandolleana)发酵液提取物的乙酸乙酯层中分离得到一个新的血苋烷型倍半萜(1)和一个已知的没药烷型倍半萜(2)。通过质谱、核磁等方法确定化合物1的结构为15-hydroxy-drimenol。通过文献对照核磁数据确定化合物2为1α-hydroxy-bisabola-2,10-dien-4-one。

关键词：白黄小脆柄菇倍半萜结构鉴定

Moment Redistribution Effect of the Continuous Glass Fiber Reinforced Polymer-Concrete Composite Slabs Based on Static Loading Experiment

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Structural Durability & Health Monitoring 2025年第1期19卷 105-123页

作者： Zhao-Jun Zhang Wen-Wei Wang Jing-Shui Zhen Bo-Cheng li De-Cheng Cai Yang-Yang Du hui Huang Offshore Oil Engineering Co.Ltd. Tianjin300461China Department of Bridge Engineering School of TransportationSoutheast UniversityNanjing211189China

This study aimed to investigate the moment redistribution in continuous glass fiber reinforced polymer(GFRP)-concrete composite slabs caused by concrete cracking and steel bar yielding in the negative bending moment *** experimental bending moment redistribution test was conducted on continuous GFRP-concrete composite slabs,and a calculation method based on the conjugate beam method was *** composite slabs were formed by combining GFRP profiles with a concrete layer and supported on steel beams to create two-span continuous composite slab *** methods,epoxy resin bonding,and stud connection,were used to connect the composite slabs with the steel *** experimental findings showed that the specimen connected with epoxy resin exhibited two moments redistribution phenomena during the loading process:concrete cracking and steel bar yielding at the internal *** contrast,the composite slab connected with steel beams by studs exhibited only one-moment redistribution phenomenon throughout the loading *** the concrete at the internal support cracked,the bending moment decreased in the internal support section and increased in the midspan *** the steel bars yielded,the bending moment further decreased in the internal support section and increased in the mid-span *** GFRP profiles do not experience cracking,there was no significant decrease in the bending moment of the mid-span *** test specimens experienced compressive failure of concrete at the mid-span *** results showed good agreement between the calculated and experimental values of bending moments in the mid-span section and internal support *** proposed model can effectively predict the moment redistribution behavior of continuous GFRP-concrete composite slabs.

关键词： Moment redistribution GFRP-concrete composite slabs bending moment experimental study analysis model

Multivariate synergy for heightening ionic HOF robustness and proton conductivity

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Science China Chemistry 2025年

作者： Xiang-Tian Bai li-hui Cao Xu-Yong Chen Jia-Yu Wang Zi-Ye Zhou Shaanxi Key Laboratory of Chemical Additives for Industry College of Chemistry and Chemical EngineeringShaanxi University of Science and Technology

Multicomponent crystalline materials construct more complex and diversified structures with different combinations and modes,which expands the material structure space and application *** this work,we have successfully synthesized two twocomponent ionic hydrogen-bonded organic frameworks （iHOF-32 and iHOF-33） and a three-component iHOF （iHOF-34）.Guanidine hydrochloride which is rich in N and H and has a short chain length strengthens the hydrogen bonding network of iHOF,thereby aiding in the efficient migration of *** rigid architecture of 1,1'-diamino-4,4'-bipyridine diiodide furnishes additional scaffolding for the iHOFs and enhances its robustness under harsh ***-34 accomplishes the combination of the ultra-high proton conductivity of iHOF-32 and the robustness of iHOF-33 by the synergistic interaction among the three components of *** addition,iHOF-34 was fabricated as a composite membrane with a peak proton conductivity of 1.55×10-1S cm-1,which is 3.8 times higher than that of recast Nafion,and has extensive potential in fuel *** self-assembly strategy of multicomponent HOFs opens up new avenues for constructing diverse structures while promising new opportunities for applications in the fields of proton conduction and energy storage.

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一部利用方言疏证《墨子》的成功之作——评萧鲁阳教授《墨子元典校理与方言研究》

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平原大学学报 2005年第2期22卷 95-98页

作者：李慧玲李正辉吕友仁中原工学院河南郑州450007 河南师范大学河南新乡453007

众所周知,在墨学研究中有两个难题:一个是墨子的里籍问题,一个是一书的艰涩难懂问题.令人高兴的是,萧鲁阳教授一书,在吸收前贤时彦研究成果的基础上,把这两个难题都解决得相当出色,从而把墨学研究提高到一个新阶段,这实在是一件值得大... 详细信息

众所周知,在墨学研究中有两个难题:一个是墨子的里籍问题,一个是一书的艰涩难懂问题.令人高兴的是,萧鲁阳教授一书,在吸收前贤时彦研究成果的基础上,把这两个难题都解决得相当出色,从而把墨学研究提高到一个新阶段,这实在是一件值得大书特书的喜事.

关键词：墨子方言教授研究成果新阶段难题

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奥氏体不锈钢半圆管夹套焊接工艺要点探讨

机械设计与制造 2009年第10期 148-149页

作者：李政辉陈如流刘建勋南京工业大学机械与动力工程学院南京210009 中国化学工程第十四建设公司南京210048 辽宁省标准化研究院沈阳110000

在化工容器和设备上采用奥氏体不锈钢焊接半圆管夹套一般具有较高要求,通过实际生产中对于不同焊接工艺的应用,本文结合奥氏体不锈钢制作化工容器和设备上焊接半圆管夹套焊缝性能要求,针对不锈钢逐段冷成形焊接在凸形封头上的半管盘管... 详细信息

在化工容器和设备上采用奥氏体不锈钢焊接半圆管夹套一般具有较高要求,通过实际生产中对于不同焊接工艺的应用,本文结合奥氏体不锈钢制作化工容器和设备上焊接半圆管夹套焊缝性能要求,针对不锈钢逐段冷成形焊接在凸形封头上的半管盘管或者是整根对半剖分盘管焊接工艺要点,总结出对于此类焊缝的焊接工艺要点和焊缝检测与试验内容,同时该焊接工艺评定的做法和评价可以应用于类似焊缝。

关键词：半圆管夹套焊接工艺焊缝检测

Activatable chemiluminescence probe based on four-arm PEGconjugated-pyropheophorbide-a for in vivo autofluorescence-free imaging of peroxynitrite

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Science China Chemistry 2025年

作者： Jianmei Ke Lei Ding Ronggui lian Cheng zheng Wenjun li Aixian zheng Yupeng Sun Ming Wu Yongyi Zeng Xiaolong liu Maochun Hong Xiaolong Zhang The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province Mengchao Hepatobiliary Hospital of Fujian Medical University Ganjiang Innovation Academy Chinese Academy of Sciences School of Rare Earths University of Science and Technology of China College of Chemistry Fuzhou University State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Peroxynitrite（ONOO-） is a highly reactive nitrogen species that plays pivotal roles in cell signal transduction and physiological or pathological progresses. However, commonly used ONOO-optical imaging probes are still hampered by high background/autofluorescence（fluorescence probe）, short emission wavelength, or poor selectivity in the case of chemiluminescence. Herein,we report a facile method to prepare an activatable chemiluminescence probe（PPA-PEG） with good biocompatibility and functionality for in vivo autofluorescence-free imaging of ONOO-. The PPA-PEG consists of pyropheophorbide-a（PPA）, a typical deep red photosensitizer that acts as both the recognition and signaling element, and 4-arm poly（ethylene glycol）(4-arm PEG), which improves the biosafety and water solubility of probe. These components can self-assemble into nanoparticles（namely PPA-PEG nanoprobe） in aqueous solution. The PPA-PEG nanoprobe showed an ultra-low chemiluminescence signal before interacting with ONOO-, but exhibited good selectivity, high sensitivity and a fast response toward ONOO-. The PPAPEG was successfully applied to image cellular ONOO-changes, as well as the endogenous ONOO-changes in inflammation models and subcutaneous or orthotopic hepatocellular carcinoma（HCC） tumors models in living mice. In vitro and in vivo studies verified the good detection and imaging capabilities of PPA-PEG for peroxynitrite, demonstrating suitable tissue penetration and a high signal-to-background ratio（SBR）. Thus, our nanoprobe can serve as a valuable activatable chemiluminescence imaging tool for studying important peroxynitrite-related chemical and biological applications.

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车用燃料电池发动机引射器优化设计

哈尔滨理工大学学报 2020年第4期25卷 19-26页

作者：贠海涛胡帅李正辉魏永琪青岛理工大学机械与汽车工程学院山东青岛266520

针对引射器在车用燃料电池发动机中的应用问题,通过对40 kw级质子交换膜燃料电池(PEMFC)阳极压降实验数据的拟合,得到了阳极压降与电流的关系表达式,利用计算流体力学(CFD)方法建立了阳极氢气循环系统三维引射器数值模型,并用实验数据... 详细信息

针对引射器在车用燃料电池发动机中的应用问题,通过对40 kw级质子交换膜燃料电池(PEMFC)阳极压降实验数据的拟合,得到了阳极压降与电流的关系表达式,利用计算流体力学(CFD)方法建立了阳极氢气循环系统三维引射器数值模型,并用实验数据对模型进行了验证,最后将拟合得到的阳极压降表达式应用于模型的仿真优化中,衡量了引射器在中低负载和高负载工况下的性能表现,确定了喷嘴喉部直径、混合室直径、混合室长度以及喷嘴出口相对混合室入口距离的最优值。仿真结果表明:与恒定压降模型相比,建立的引射器模型可以更准确的评估引射器在整个工况下的工作性能,同时在所研究的运行工况下,优化后的引射器可以维持氢气回流比在1.2以上。

关键词：质子交换膜燃料电池阳极压降引射器仿真优化

Laser-Induced Fluorescence Bronchoscopy for Detection and Localization of Early Lung Cancer

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Chinese Journal of Lasers 2001年第4期 70-76页

作者： XIE Shusen 1,2 li Buhong 1,2 li hui 1 zheng Wei 1,3 LU Zukang 2 1) Biomedical Optical Lab, Institute of Laser, Fujian Teachers University, Fuzhou 35007, China 2) National Research Center of Optical Instrument Engineering, Zh

Experimenatal results on the development of a Laser Induced Fluorescence Bronchoscopy(liFB) for the detection and localization of early lung cancer are reported in this paper. The system utilizes fluorescence of photosensitizer drug to provide real time video imaging for the examined lung tissue. Color filters are used to differentiate signal from background and a computer image processing technique is also applied to subtract the background. Moreover, a pseudocolor contrast enhancement method was developed to enhance the fluorescence image displayed on the vidio monitor. Suspicious areas are identified by pseudocolor image to guide biopsy, and several clinical trials show that sensitivity and contrast capability of the system should permit the detection and localization of early lung cancer.

关键词： laser induced fluorescence early lung cancer detection and localization computer image processing

国内外豆类期货价格传导实证研究——基于分布滞后回归模型

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怀化学院学报 2014年第9期33卷 55-59页

作者：李正辉李磊何融湖南大学金融与统计学院湖南长沙410079

用分布滞后回归模型分别研究大豆、豆粕和豆油在国内期货市场和芝加哥期货市场间的传导。从豆类各品种在大连期货交易所和芝加哥期货市场之间的传导特点可以看出,豆类期货价格在国内外的传导具有非对称性。总体来说我国豆类期货价格对... 详细信息

用分布滞后回归模型分别研究大豆、豆粕和豆油在国内期货市场和芝加哥期货市场间的传导。从豆类各品种在大连期货交易所和芝加哥期货市场之间的传导特点可以看出,豆类期货价格在国内外的传导具有非对称性。总体来说我国豆类期货价格对芝加哥期货市场的影响力要大于芝加哥期货市场对我国期货市场的影响力,特别显著的是我国大连大豆和豆粕期货都是芝加哥大豆和豆粕期货的格兰杰原因,而反之不成立。虽然大连豆油期货和芝加哥豆油期货价格间的传导互为因果,但是从分布滞后模型的回归结果可以看出,我国大连豆油期货对芝加哥豆油期货价格的影响力要大于芝加哥豆油期货对大连豆油期货的影响力。

关键词：农产品期货分布滞后回归传导机制