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Photochromic radical states in 3D covalent organic frameworks with zyg topology for enhanced photocatalysis

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National Science Review 2024年第07期 177-188页

作者： Tian-Tian Ma Guo-Zhang Huang Xiao-Han Wang yan liang Run-Han li Bin Wang su-juan yao Jia-Peng liao Shun-li li Yong yan ya-Qian Lan School of Chemistry South China Normal University Department of Chemistry Guangdong Provincial Key Laboratory of Catalytic Chemistry Southern University of Science and Technology

Covalent-organic frameworks（COFs） with photoinduced donor-acceptor（D-A） radical pairs show enhanced photocatalytic activity in principle. However, achieving long-lived charge separation in COFs proves challenging due to the rapid charge recombination. Here, we develop a novel strategy by combining[6 + 4] nodes to construct zyg-type 3D COFs, first reported in COF chemistry. This structure type exhibits a fused Olympic-rings-like shape, which provides a platform for stabilizing the photoinduced D-A radical pairs. The zyg-type COFs containing catalytically active moieties such as triphenylamine and phenothiazine（PTZ） show superior photocatalytic production rates of hydrogen peroxide（H2O2）. Significantly, the photochromic radical states of these COFs show up to 400% enhancement in photocatalytic activity compared to the parent states, achieving a remarkable H2O2synthesis rate of 3324 μmol g-1h-1, which makes the PTZ-COF one of the best crystalline porous photocatalysts in H2O2production. This work will shed light on the synthesis of efficient 3D COF photocatalysts built on topologies that can facilitate photogenerating D-A radical pairs for enhanced photocatalysis.

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拔节期渍水对软质小麦淀粉粒度分布与糊化特性的影响

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作物学报 2024年第7期50卷 1877-1884页

作者：陈娟杨婷婷闫素辉雍玉东张士雅李文阳安徽科技学院农学院安徽凤阳233100

为明确拔节期渍水对软质小麦淀粉粒度分布与糊化特性的影响。在大田条件下,于2021—2023年,选用软质小麦品种华成麦1688和荃麦725为试验材料,设对照(CK)和渍水(WL)2种处理,在小麦拔节期进行连续10 d的渍水处理,研究拔节期渍水对软质小... 详细信息

为明确拔节期渍水对软质小麦淀粉粒度分布与糊化特性的影响。在大田条件下,于2021—2023年,选用软质小麦品种华成麦1688和荃麦725为试验材料,设对照(CK)和渍水(WL)2种处理,在小麦拔节期进行连续10 d的渍水处理,研究拔节期渍水对软质小麦淀粉粒度分布及黏度参数的影响及其相互关系。结果表明,与对照相比,拔节期渍水胁迫通过降低小麦穗数、穗粒数及千粒重,从而降低小麦产量,籽粒湿面筋含量、蛋白质含量显著降低,淀粉含量显著增加。拔节期渍水胁迫抑制了小麦胚乳B淀粉的产生和生长,使小麦B型淀粉粒体积、表面积及数目百分比显著降低,其中主要影响2.8~10.0μm的淀粉粒;A型淀粉粒体积、表面积百分比显著增加,以影响其中10.0~22.0μm的淀粉粒为主,渍水胁迫对A型淀粉粒数目百分比无显著性影响。渍水胁迫后,面粉峰值黏度、低谷黏度、最终黏度、稀懈值及回升值显著增加。可见,拔节期渍水胁迫改变了小麦淀粉粒度分布,通过降低B型淀粉粒占比,增加A型淀粉粒占比,进而增加峰值黏度等黏度参数,最终影响小麦籽粒品质。

关键词：小麦淀粉粒淀粉粒度分布糊化特性渍水

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基于双斜坡法的光纤应变快速测量方法

科学技术与工程 2024年第16期24卷 6749-6756页

作者：董艳唯王浩孙昭张春晖李琳李苏雅陈永辉国网天津市电力公司电力科学研究院天津300384 华北电力大学电子与通信工程系保定071003

为了提高基于布里渊散射的光纤应变测量的实时性,将仅根据两个工作点布里渊增益计算布里渊频移的双斜坡法用于光纤应变测量。介绍双斜坡法的基本原理,基于仿真布里渊谱研究左右两侧工作点选择对布里渊频移计算准确性的影响规律,确定最... 详细信息

为了提高基于布里渊散射的光纤应变测量的实时性,将仅根据两个工作点布里渊增益计算布里渊频移的双斜坡法用于光纤应变测量。介绍双斜坡法的基本原理,基于仿真布里渊谱研究左右两侧工作点选择对布里渊频移计算准确性的影响规律,确定最佳的工作点。基于确定的最佳工作点和不同信噪比的布里渊谱,研究信噪比(signal-to-noise ratio, SNR)对双斜坡法和最小二乘拟合法准确性的影响规律。结果表明:双斜坡法的两个工作点围绕光纤沿线布里渊频移的均值对称时误差最小;随两个工作点频率之差的增加布里渊频移误差先减小后增大。相似准确性下双斜坡法的布里渊谱测量时间仅为最小二乘拟合法的约1/30,布里渊频移的计算时间仅约为后者的1/480。

关键词：布里渊散射分布式光纤传感双斜坡法快速应变测量

多学科协作团队干预早期肠内营养对危重症患者肺部感染的效果

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中华医院感染学杂志 2024年第3期34卷 465-468页

作者：苏婧李亚男南锐伶许娟王小艳张正馨兰州大学第二医院急救中心甘肃兰州730000 兰州大学第二医院急危重症三病区甘肃兰州730000 兰州大学第二医院神内ICU 甘肃兰州730000 兰州大学第二医院普外ICU 甘肃兰州730000 兰州大学第二医院急危重症二病区甘肃兰州730000

目的探究多学科协作团队(MDT)干预早期肠内营养对危重症患者肺部感染率的效果.方法选择2021年1月-2022年8月兰州大学第二医院急诊科收治的98例ICU重症患者为研究对象,随机分为研究组与对照组,各49例,对照组给予常规的肠外营养支持,研究... 详细信息

目的探究多学科协作团队(MDT)干预早期肠内营养对危重症患者肺部感染率的效果.方法选择2021年1月-2022年8月兰州大学第二医院急诊科收治的98例ICU重症患者为研究对象,随机分为研究组与对照组,各49例,对照组给予常规的肠外营养支持,研究组予以MDT营养管理模式.对比干预前、干预10天后,两组患者营养指标、免疫功能指标及住院期间肺部感染率、早期康复指标及胃肠道并发症情况.结果对照组肺部感染感染率为18.37%(9/49)高于研究组(P=0.008);10天营养支持后,研究组前清蛋白(PA)较干预前升高(P<0.05),且总蛋白(TP)、血红蛋白(Hb)、PA及清蛋白(ALB)水平均高于对照组(P<0.05);研究组免疫球蛋白A(IgA)、IgG、IgM高于干预前及对照组(P<0.05),对照组IgA、IgM高于治疗前(P<0.05);研究组的呼吸机待机时间、首次经口进食时间、拔出胃管时间及拔出尿管时间均短于对照组(P<0.05);两组患者胃肠道并发症发生率差异无统计学意义.结论MDT协作团队实施的早期肠内营养干预可改善免疫功能及营养状态,降低危重症患者肺部感染率,减少并发症发生率.

关键词：多学科团队协作早期肠内营养危重症患者肺部感染干预

liquid crystal character controlled by complementary discotic molecules mixtures： Columnar stacking type and mesophase temperature range

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Chinese Chemical Letters 2016年第3期27卷 475-480页

作者： yan li Ming-Guang li ya-Jun su Jian-Gang liu yan-chun Han Shi-Jun Zheng li-Xiang Wang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China University of the Chinese Academy of Sciences Beijing 100049 China School of Materials Science and Engineering Zhengzhou University Zhengzhou 450052 China

In this work, the mesophase properties were tuned via mixing two discotic molecules with structural complementarity. Compared with the liquid crystalline hexakis（n-hexyloxy）triphenylene（H6TP）materials（columnar hexagonal phase from 53 ℃ to 91 ℃）, mesophase types as well as phase transition temperatures varied with the introduction of crystalline hexaazatriphenylene derivative（PBH）molecules. The introduction of less than 33% amount of PBH disrupted the columnar hexagonal phase formed by H6 TP remarkably, followed by the decreased clearing temperatures of liquid crystals. As the PBH amount was further increased, the destroyed columnar hexagonal phase was turned into the columnar rectangular phase, in which H6 TP and PBH molecules together formed the columnar mesophase. The formation of new mesophase contributed to the enlarged mesophase temperature（from44 ℃ to 144 ℃）. We speculated that the alkyl chains interaction induced by the PBH component competed with the strong p–p stacking between H6 TP molecules, thus altering the liquid crystalline properties including mesophase types and phase transition temperatures.

关键词： Alkyl chains packing Mesophase type liquid crystals Phase transitions Mixture

PREPARATION OF SOLUBLE suBSTITUTED POLyaCETYLENE OPTICAL liMITING MATERIAL

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Chinese Journal of Polymer Science 2006年第3期24卷 221-227页

作者： Shou-chun Yin 徐洪耀 Gang li Xin-yan su ya-chen Gao Yin-lin Song Ben-zhong Tang Department of Chemistry ＆ the Key Laboratory of Environment-friendly Polymer Materials of Anhui Province Anhui University Hefei 230039 China Department of Physics Harbin Institute of Technology Harbin 150001 China Department of Chemistry Hong Kong University of Science and Technology Kowloon Hong Kong China

Two novel polyacetylenes bearing nonlinear optical chromophoric group poly（3-（4-[4-（n-butyloxy） phenylazophenyl]carbonyl）oxy-1-propyne）（poly（1a）） and poly（3-（4-[4-（n-heptyloxy）phenylazophenyl]carbonyl）-oxy-l- propyne）（poly（lb）） were synthesized with [Rh（nbd）Cl]2-EtaN as catalysts. These polyacetylenes are soluble by using an alkyl spacer and an alkyloxyl group as a substituent. They were characterized by FTIR, NMR, GPC and UV-Vis and their optical limiting and nonlinear optical properties were investigated using 8 ns pulse at 532 nm wavenumber. The results show that these soluble functional polyacetylenes possess optical limiting properties and large nonlinear optical properties and poly（1b） possesses better optical limiting and nonlinear optical properties than poly（ 1 a）.

关键词： Polyacetylene Optical limiting Nonlinear optics Azobenzene.

An Abietane Diterpene and a Sterol from Fungus Phellinus igniarius

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Chinese Chemical Letters 2006年第4期17卷 481-484页

作者： Ying WANG su juan WANG Shun yan MO Shuai li Yong chun yanG Jian Gong SHI Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union MedicalCollege （Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine Ministry of Education） Beijing 100050 Key Laboratory for Atmospheric Chemistry Centre for Atmosphcre Watch and Services Chinese Academy of Meteorological Sciences CMA Beijing 100081

A new abietane diterpene 12-hydroxy-7-oxo-5, 8, 11, 13-tetraene-18, 6-abietanolide, together with a new natural sterol stigmasta-7, 22-diene-3β, 5α 6α-triol have been isolated from the fruiting body of the fungus P... 详细信息

关键词： Phellinus igniarius Polyporaceae fungus diterpene sterol.

粉末压片-波长色散X射线荧光光谱法测定炼钢尾渣中化学成分

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中国检验检测 2024年第2期32卷 62-66页

作者：王莉敏孙娟于春波闫丽苏红梅北京首钢股份有限公司北京064400

本文介绍了一种X射线荧光粉末压片法分析炼钢尾渣中TFe、SiO_(2)、CaO、MgO化学成分的方法,该方法具有操作简单、分析速度快、节省人力、减少化学试剂使用和废液排放、降低分析成本等优点。通过对化学湿法、X射线荧光玻璃熔片分析法与X... 详细信息

本文介绍了一种X射线荧光粉末压片法分析炼钢尾渣中TFe、SiO_(2)、CaO、MgO化学成分的方法,该方法具有操作简单、分析速度快、节省人力、减少化学试剂使用和废液排放、降低分析成本等优点。通过对化学湿法、X射线荧光玻璃熔片分析法与X射线荧光粉末压片分析法数据进行统计分析,最终确定了X射线荧光粉末压片分析法替代化学湿法及X射线荧光玻璃熔片分析法分析炼钢尾渣中TFe、SiO_(2)、CaO、MgO化学成分,该方法满足生产对准确性和及时性的要求。

关键词：粉末压片炼钢尾渣 X射线荧光光谱法

Erectile dysfunction is associated with subclinical carotid vascular disease in young men lacking widely-known risk factors

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Asian Journal of Andrology 2018年第4期20卷 400-404页

作者： Feng-juan yao ya-Dong Zhang Zi Wan Wei li Hong lin chun-Hua Deng yan Zhang Department of Ultrasound First Affiliated Hospital Sun Yat-sen University Guangzhou 510080 China Department of Urology First Affiliated Hospital Sun Yat-sen University Guangzhou 510080 China Division of Cardiovascular Rehabilitation Hear Center Key Laboratory on Assisted Circulation Ministry of Health First Affiliated Hospital Sun Yat-sen University Guangzhou 510080 China

This study aimed to gain insight into the underlying pathogenesis of erectile dysfunction in young men under the age of 40 years without widely-known risk factors. Compared with normal controls, patients with erectile dysfunction had increased carotid intima- media thickness, fasting levels of blood glucose and insulin, and homeostatic model assessment index, as well as lower flow-mediated vasodilation and testosterone levels （P 〈 0.05）, though all of these values were within their respective normal range. Multivariate logistic regression analysis identified carotid intima-media thickness, flow-mediated vasodilation, insulin level, and homeostatic model assessment index as significant predictors of erectile dysfunction. Young men with flow-mediated vasodilation 〈10.65% were 11.645 times more likely to have erectile dysfunction, young men with carotid intima-media thickness 〉0.623 mm had a 4.16-fold, and young men with homeostatic model assessment index 〉1.614 had a 5.993-fold greater risk of having erectile dysfunction. In conclusions, in young men with normal results from general clinical screening, an increased carotid intima-media thickness and homeostatic model assessment index and reduced flow-mediated vasodilation were associated with a higher incidence of erectile dysfunction. Erectile dysfunction may appear before the detection of traditional cardiovascular risk factors and may be the earliest clinical sign of subclinical cardiovascular disease.

关键词： endothelial dysfunction erectile dysfunction intima-media thickness risk factors