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芦荟大黄素对α-葡萄糖苷酶的抑制作用及机理

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食品与发酵工业 2024年第10期50卷 134-140,I0001页

作者：潘若瑶任国艳马富利彭琪越杜鹂莹河南科技大学食品与生物工程学院河南洛阳471000 河南省食品原料工程研究中心河南洛阳471000 国家实验食品加工与安全教育示范中心河南洛阳471000

抑制α-葡萄糖苷酶活性是控制机体血糖平衡的有效途径。该文通过酶活性实验、紫外光谱法、荧光光谱法、傅里叶变换红外光谱和分子对接等方法研究了芦荟大黄素(aloe-emodin,AE)对α-葡萄糖苷酶的抑制作用及机理。结果表明,AE对α-葡萄糖... 详细信息

抑制α-葡萄糖苷酶活性是控制机体血糖平衡的有效途径。该文通过酶活性实验、紫外光谱法、荧光光谱法、傅里叶变换红外光谱和分子对接等方法研究了芦荟大黄素(aloe-emodin,AE)对α-葡萄糖苷酶的抑制作用及机理。结果表明,AE对α-葡萄糖苷酶活性有显著抑制作用[IC_(50)=(0.031±0.001)mg/mL],抑制类型为混合型抑制。AE通过一个结合位点与酶结合,使酶中的荧光基团发生静态猝灭。AE改变了酶的构象,使酶的α-螺旋、β-转角含量降低,β-折叠、无规则卷曲含量增加。分子对接深入分析结果显示,AE与Thr290、Leu297、Glu296和Asn2592形成氢键,与Leu297等形成范德华力。AE通过这些分子间作用力结合到α-葡萄糖苷酶的疏水结合腔内,改变了酶的构象,使酶活性降低。

关键词：芦荟大黄素 α-葡萄糖苷酶抑制作用光谱分子对接

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碱性激发矿渣对水泥混凝土界面影响行为研究

金属矿山 2024年第7期 276-280页

作者：韩向明韩鹏举马富丽山西工程科技职业大学工程管理学院山西晋中030619 太原理工大学土木工程学院山西太原030000

针对碱激发矿渣影响水泥混凝土的力学性能和界面性能等问题,采用变掺量法,将碱激发矿渣的替代率为0%、10%、20%和30%,采用扫描电子显微镜测试分析了碱激发矿渣对水泥混凝土力学性能和微观界面特征的影响。结果表明:①碱激发矿渣水泥混... 详细信息

针对碱激发矿渣影响水泥混凝土的力学性能和界面性能等问题,采用变掺量法,将碱激发矿渣的替代率为0%、10%、20%和30%,采用扫描电子显微镜测试分析了碱激发矿渣对水泥混凝土力学性能和微观界面特征的影响。结果表明:①碱激发矿渣水泥混凝土的轴心抗压强度随着矿渣掺量增加而降低,立方体抗压强度随着矿渣掺量增加而增加;②碱激发矿渣掺量水泥混凝土试件的峰值应力越高,应力—应变曲线越陡,低掺量试件的刚度和弹性模量较低,高掺量试件的应力—应变曲线下降斜率最小,其延性和变形能力优于其他试件,碱激发矿渣可以穿透水泥混凝土的细裂缝,从而提高基体的劈裂抗拉强度;③微观结构中存在由干燥收缩引起的微裂纹和孔隙,随着碱激发矿渣掺量增加,水泥砂浆微观结构上的微裂纹和孔洞越来越少;④高掺量试件的碱激发矿渣界面较为致密,微裂纹少,在碱激发矿渣表面和孔洞上附着较多的凝胶材料,这些凝胶材料基本沿着界面分布。

关键词：碱性激发矿渣抗压强度应力—应变曲线劈裂抗拉强度 SEM 混凝土

基于BP-DEmaTEL的山西省冬小麦水足迹影响因素识别

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水资源保护 2024年第2期40卷 9-15页

作者：韩宇平马伏枥贾冬冬黄会平张庚辰苗浩东华北水利水电大学水资源学院河南郑州450045 华北水利水电大学河南省黄河流域水资源节约集约利用重点实验室河南郑州450045

针对山西省冬小麦水足迹历史演变及关键影响因素识别问题,分析了1993—2021年山西省冬小麦水足迹历史演变规律,利用BP神经网络-决策实验室(BP-DEmaTEL)模型对冬小麦水足迹演变的关键影响因素进行识别,将其分为驱动型因素及特征型因素,... 详细信息

针对山西省冬小麦水足迹历史演变及关键影响因素识别问题,分析了1993—2021年山西省冬小麦水足迹历史演变规律,利用BP神经网络-决策实验室(BP-DEmaTEL)模型对冬小麦水足迹演变的关键影响因素进行识别,将其分为驱动型因素及特征型因素,并揭示了影响因素之间的作用机制。结果表明:1993—2021年山西省冬小麦水足迹及单位水足迹均呈下降趋势;2021年山西省冬小麦总水足迹为27亿m^(3)(蓝水占比57%),单位水足迹为1 122 m^(3)/t,与前期高点相比分别下降38%(较1994年)和21%(较1993年);气温、相对湿度和灌溉面积为冬小麦水足迹演变的关键驱动型因素,化肥施用量和农业机械总动力为关键特征型因素。

关键词： BP神经网络-决策实验室模型水足迹冬小麦山西省

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西双版纳户外运动进校园SWOT分析

体育科学进展 2024年第2期12卷 277-282页

作者：马富莉杨亚坤李茂维云南大学体育学院云南昆明

本文以西双版纳户外运动进校园为研究内容,运用SWOT分析法分析了其优势(Strengths)、劣势(Weaknesses)、机会(Opportunities)、威胁(Threats),旨在对西双版纳户外运动进校园进行综合性分析,并提出相关建议。研究表明,西双版纳户外运动... 详细信息

本文以西双版纳户外运动进校园为研究内容,运用SWOT分析法分析了其优势(Strengths)、劣势(Weaknesses)、机会(Opportunities)、威胁(Threats),旨在对西双版纳户外运动进校园进行综合性分析,并提出相关建议。研究表明,西双版纳户外运动进校园的价值分别有:利于户外运动的推广和普及、丰富学校教育内容、培养学生综合能力、促进健康发展。户外运动进校园的优势在于;得天独厚的自然资源、多元民族文化优势、蓬勃发展的旅游业。其劣势在于:教育资源和专业指导不足、户外运动开展设施不足。其机会在于:国家政策与政府支持。其威胁在于:安全风险问题、学生与家长对户外运动认知不足、环境保护与可持续发展问题。

关键词：学校体育户外运动 SWOT分析西双版纳

On the measurements of individual particle properties via compression and crushing

维普期刊数据库博看期刊评论

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第2期13卷 377-389页

作者： Chunlong Liu Fengyin Liu Jinliang Song fuli ma Dongfang Wang Guoping Zhang Institute of Geotechnical Engineering Xi’an University of TechnologyXi’an710048China Department of Civil and Environmental Engineering University of Massachusetts AmherstAmherstMA01003USA State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China College of Architecture and Civil Engineering Taiyuan University of TechnologyTaiyuan030024China

An experimental study is presented to measure the elastic,yielding,and crushing properties of individual particles under compression using substrates made of aluminum alloy,stainless steel,and *** selected,highly spherical individual Ottawa sand particles of 0.75e1.1 mm in nominal diameter were compressed between two smooth substrates,and the loadedeformation curves were analyzed by Hertz elastic contact theory to derive their reduced modulus and Young’s modulus as well as yielding and crushing strengths,which vary significantly with the type of substrate *** analysis of the yielding and plastic deformation at the particle-substrate contact shows that the yield strength or hardness of the substrate materials dominates the local contact behavior and hence affects the measured apparent yielding and crushing *** two softer substrates(aluminum alloy and stainless steel)actually lead to underestimated apparent shear yield strengths of quartz particles by 60.4%and 54.2%,respectively,which are actually the yielding of substrates,while the true particle yielding occurs in the sapphire-particle ***,the two softer substrates cause much overestimated crushing strengths of the quartz particles by 50.4%and 36.4%,*** of inappropriate substrate materials and inappropriate interpretation of the particle-substrate contact can lead to significant errors in the measured yielding and crushing *** is recommended that single particle compression testing uses substrates with yield strength greater than that of the tested particles and result interpretation also considers the elastic and yielding behaviors of the substrates.

关键词： Elasticity Hertz contact Particle crushing Strength Yielding Weibull distribution

Effects of Coal Metakaolin on the Mechanical Properties and Microstructure of High-belite Sulphoaluminate Cement

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Journal of Wuhan University of Technology(materials Science) 2023年第2期38卷 342-352页

作者： WANG Xingyi HAN Pengju NIU Shiwei HE Bin ma fuli GUO Tiantian XU Jinchuan College of Civil Engineering Taiyuan University of TechnologyTaiyuan030024China Yellow River Engineering Consulting Co. LtdZhengzhou450003China

The effects of coal metakaolin on the mechanical properties of high-belite sulphoaluminate cement under compressive loading were *** composition and microstructure of hydration products at different hydration times were analyzed by X-ray diffraction and scanning electronic *** hydration process of blended cement was studied via electrochemical impedance *** particular,replacing a part of cement with CMK(10%,20%,and 30%)was found to promote the hydration process,to refine the pore size,and to improve the compressive strength of the *** best compressive strength of the cement was achieved at a CMK content of 30%after 28 days hydration,being improved by 20.13 MPa,or1.44 times relative to that of undoped ***,the compressive strength is shown to correlate with the impedance parameter R_(CCP),which allows the latter to be used for nondestructive assessment of the compressive strength of blended cement materials.

关键词： coal metakaolin compressive strength microstructure electrochemical impedance spectroscopy impedance parameter

EFFICIENT RATE-COMPATIBLE PUNCTURING SCHEME FOR LOW-DENSITY PARITY-CHECK CODES

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EFFICIENT RATE-COMPATIBLE PUNCTURING SCHEME FOR LOW-DENSITY ...

The 2011 International Conference on Mechanical Engineering and Technology

作者： fuli ma Lijun Zhang School of Electronic and Information Engineering Beijing Jiaotong University

An efficient rate-compatible（RC） puncturing scheme for LDPC codes is proposed, which tries to distribute the punctured bits as evenly as possible while maximizing the number of 1-SR nodes in Tanner graph. The puncturing scheme can produce RC LDPC with rates ranging from the mother code rate through even 1. Simulation results show that the new puncturing method is superior to random puncturing and the method in [2].

关键词： LDPC codes rate-compatible punctured

来源： cnki会议评论

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中国当代新诗史上的“灰娃现象”

南方文坛 2021年第5期 102-109页

作者：马富丽首都师范大学中国诗歌研究中心

诗人灰娃拥有传奇般的人生经历和特殊的诗歌写作经验,有学者认为她及其诗歌创作已成为一个令人无法忽视的诗坛现象——"灰娃现象"。诗歌评论家吴思敬较早提出"灰娃是当代诗歌创作中一个独特的现象"①,学者李兆忠则最早使用"灰娃现象"这... 详细信息

诗人灰娃拥有传奇般的人生经历和特殊的诗歌写作经验,有学者认为她及其诗歌创作已成为一个令人无法忽视的诗坛现象——"灰娃现象"。诗歌评论家吴思敬较早提出"灰娃是当代诗歌创作中一个独特的现象"①,学者李兆忠则最早使用"灰娃现象"这一概括称谓,他认为:"灰娃的创作留给人们许多启示,她构成一个极为独特的艺术现象——‘灰娃现象’,是与‘何其芳现象’‘郭沫若现象’完全不同的、值得珍视的现象。"

关键词：当代新诗当代诗歌吴思敬何其芳现象诗歌写作诗歌创作郭沫若现象人生经历

Internal Polarization Field Induced Hydroxyl Spillover Effect for Industrial Water Splitting Electrolyzers

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Nano-Micro Letters 2024年第2期16卷 438-449页

作者： Jingyi Xie fuli Wang Yanan Zhou Yiwen Dong Yongming Chai Bin Dong State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580People’s Republic of China

The formation of multiple oxygen intermediates supporting efficient oxygen evolution reaction(OER)are affinitive with hydroxyl ***,ability of the catalyst to capture hydroxyl and maintain the continuous supply at active sits remains a tremendous ***,an affordable Ni2P/FeP2 heterostructure is presented to form the internal polarization field(IPF),arising hydroxyl spillover(HOSo)during *** by IPF,the oriented HOSo from FeP2 to Ni2P can activate the Ni site with a new hydroxyl transmission channel and build the optimized reaction path of oxygen intermediates for lower adsorption energy,boosting the OER activity(242 mV *** at 100 ma cm-2)for least 100 *** interestingly,for the anion exchange membrane water electrolyzer(AEMWE)with low concentration electrolyte,the advantage of HOSo effect is significantly amplified,delivering 1 A cm^(-2)at a low cell voltage of 1.88 V with excellent stability for over 50 h.

关键词： Hydroxyl spillover effect Internal polarization field Heterostructure Oxygen reduction reaction Anion exchange membrane water electrolysis