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遮荫对‘花手鞠’绣球花色和花青素苷组成的影响

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园艺学报 2023年第7期50卷 1467-1481页

作者：杨君孔羽刘群录叶康秦俊上海辰山植物园城市园艺技术研发和推广中心上海201602 上海交通大学设计学院上海200240

以‘花手鞠’绣球(Hydrangea macrophylla‘Hanatemari’)为试材,研究全光照和50%遮荫对其不同开花时期花色和花青素苷组成的影响。采用英国皇家园艺学会比色卡和测色仪测定花色表型;利用高效液相色谱质谱联用技术(LC–MS)定性和定量分... 详细信息

以‘花手鞠’绣球(Hydrangea macrophylla‘Hanatemari’)为试材,研究全光照和50%遮荫对其不同开花时期花色和花青素苷组成的影响。采用英国皇家园艺学会比色卡和测色仪测定花色表型;利用高效液相色谱质谱联用技术(LC–MS)定性和定量分析花青素苷组分,并测定色素生物合成关键酶活性和金属离子含量等生理指标;运用多元线性回归法分析花色和生理指标间的关系。结果表明:与全光照相比,50%遮荫的萼片红度值(a^(*))更低,黄度值(b^(*))更高,在色彩上更偏粉色;从盛花期到末花期,全光照的花萼红度值(a^(*))下降88.90%;而50%遮荫仅下降65.67%,有效减缓了花萼的褪色速率。花萼中共检测到矢车菊素、天竺葵素、飞燕草素、锦葵素和矮牵牛素等5种花青素苷元形成的11种花青素苷;主要组分为飞燕草-3-o-葡萄糖苷,占总花青素苷组分的92.12%,是‘花手鞠’花萼主要的呈色物质。50%遮荫有利于花青素苷的累积,其总花青素苷含量(1286.96μg·g^(-1)FW)较全光照(944.10μg·g^(-1)FW)显著增加了36.32%;初开期苯丙氨酸解氨酶(PAL)活性和查尔酮异构酶(CHI)活性较高,现蕾期50%遮荫下PAL酶活性显著高于全光照;遮荫并未引起花萼中Al、Fe、Ca和Mg元素含量的显著变化。多元回归结果显示,飞燕草素、锦葵素和矮牵牛素的累积有利于绣球花萼呈现红色;总花青素苷含量对绣球花萼呈色起主导作用,并与总黄酮、总酚、PAL酶和CHI酶协同作用,共同影响花色的呈现。

关键词：绣球花青素苷花色遮荫

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顺丁烯二酸酐羧化淀粉的制备

应用化学 2005年第6期22卷 643-646页

作者：萧聪明叶俊华侨大学材料科学与工程学院泉州362021

研究了反应温度、反应时间、投料比和介质中水含量等因素对反应产物羧化度和取代度的影响,获得了顺丁烯二酸酐与淀粉进行酯化反应的较适宜条件为6g淀粉与6g顺丁烯二酸酐以6mL吡啶为催化剂,30℃下在7mL水和30mLN,N二甲基甲酰胺的混合介... 详细信息

研究了反应温度、反应时间、投料比和介质中水含量等因素对反应产物羧化度和取代度的影响,获得了顺丁烯二酸酐与淀粉进行酯化反应的较适宜条件为6g淀粉与6g顺丁烯二酸酐以6mL吡啶为催化剂,30℃下在7mL水和30mLN,N二甲基甲酰胺的混合介质中反应9h,制得羧化度及取代度分别为34.7%和0.868的顺丁烯二酸淀粉单羧基酯。12g淀粉与10g顺丁烯二酸酐在1.5g过硫酸钾的引发下,95℃下以30mL水为介质反应4h,也得到羧化淀粉衍生物,其羧化度及取代度分别为42.7%和1.22。FTIR分析确定了上述2种反应产物的结构,X射线衍射分析结果表明,2种淀粉衍生物的结晶度均低于纯淀粉。

关键词：淀粉顺丁烯二酸酐羧化

Revealing alkali metal ions transport mechanism in the atomic channels of Au@a-Mno_(2)

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Journal of Energy Chemistry 2023年第7期82卷 350-358,I0008页

作者： Jingzhao Chen Yo.g Su Ho.gjun ye Yushu Tang Jito.g Yan Zhiying gao Dingding Zhu Jingming Yao Xuedo.g Zhang Tingting Yang Baiyu guo Hui Li Qiushi Dai Yali Liang jun Ma Bo Wang Haiming Sun Qiunan Liu Jing Wang Co.gco.g Du Liqiang Zhang Yo.gfu Tang Jianyu Huang Clean Nano Energy Center State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdao 066004HebeiChina School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105HunanChina Hebei Key Laboratory of Applied Chemistry College of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao 066004HebeiChina

Understanding alkali metal ions’(e.g.,Li^(+)/Na^(+)/K^(+))transport mechanism is challenging but critical to improving the performance of alkali metal *** using a-Mno_(2)nanowires as cathodes,the transport kinetics of Li^(+)/Na^(+)/K^(+)in the 2×2 channels of a-Mno_(2)with a growth direction of[001]is *** show that ion radius plays a decisive role in determining the ion transport and *** of the ion radii,Li^(+)/Na^(+)/K^(+)can all go thro.gh the 2×2 channels of a-Mno_(2),generating large stress and causing channel merging or ***,smaller ions such as Li^(+)and Na^(+)cannot only transport alo.g the[001]direction but also migrate alo.g thedirection to the nanowire surface;for large ion such as K^(+),diffusion alo.g thedirection is *** different ion transport behavior has grand consequences in the electrochemistry of metal oxygen batteries(MoBs).For Li-o_(2)battery,Li^(+)transports uniformly to the nanowire surface,forming a uniform layer of oxide;Na^(+)also transports to the nanowire surface but may be clo.ged locally due to its larger radius,therefore sporadic pearl-like oxides form on the nanowire surface;K^(+)cannot transport to the nanowire surface due to its large radius,instead,it breaks the nanowire locally,causing local deposition of potassium *** study provides atomic scale understanding of the alkali metal ion transport mechanism which may be harnessed to improve the performance of MoBs.

关键词： Ion transport In-situ TEM STEM Metal oxygen batteries Metal ion batteries

纤维素醋酸丁酸酯/碳纳米管混合基质膜的气体分离性能

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高分子学报 2015年第12期25卷 1396-1401页

作者：丰晔张金明张军中国科学院化学研究所中国科学院工程塑料重点实验室北京分子科学国家实验室北京100190 中国科学院大学北京100049

通过溶液复合-溶液成膜的方法,制备了一系列纤维素醋酸丁酸酯（CAB）/多壁碳纳米管（MWCNTs）的新型混合基质膜.表征了CAB/MWCNTs膜材料的形貌、结构与力学性能.结果表明,MWCNTs与CAB界面未见明显缺陷存在,混合基质膜材料具有良好的力... 详细信息

通过溶液复合-溶液成膜的方法,制备了一系列纤维素醋酸丁酸酯（CAB）/多壁碳纳米管（MWCNTs）的新型混合基质膜.表征了CAB/MWCNTs膜材料的形貌、结构与力学性能.结果表明,MWCNTs与CAB界面未见明显缺陷存在,混合基质膜材料具有良好的力学性能.进一步考察了不同MWCNTs含量（2 wt%~30wt%）对CAB/MWCNTs混合基质膜材料的气体分离性能的影响.发现,随着混合基质膜中MWCNTs含量的增加,其对几种测试气体（o2、N2、CH4、Co和Co2）的渗透系数均明显提高,尤其是常见气体对中的＂快气＂——o2和Co2的渗透系数提高显著：当MWCNTs含量为30 wt%时,所制备的混合基质膜对o2和Co2渗透系数分别达到40.24和180.20 Barrer,比纯CAB膜分别提高了约300%和260%;同时,混合基质膜对多种气体对均表现出优异的分离效果.

关键词：纤维素醋酸丁酸酯多壁碳纳米管气体分离混合基质膜

Structural diversification of phenylspirodrimane lactams by employing a biosynthetic intermediate

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Chinese Chemical Letters 2023年第12期34卷 141-145页

作者： Jimei Liu Zhenfei Wang jun Wu Yaotian Han Fei ye Tiantai Zhang Haibo Yu Zhengshun Wen jungui Dai State Key Laboratory of Bioactive Substance and Function of Natural Medicines CAMS Key Laboratory of Enzyme and Biocatalysis of Natural DrugsNHC Key Laboratory of Biosynthesis of Natural Productsand Beijing Key Laboratory of Non-Clinical Drug Metabolism and PK/PD StudyInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Zhejiang Provincial Engineering Technology Research Center of Marine Biomedical Products School of Food Science and PharmaceuticsZhejiang Ocean UniversityZhoushan316022China

Phenylspirodrimanes are a kind of meroterpenoids with structural diversity and complexity,exhibiting a wide of biological properties,especially for the lactam derivatives consisting a y-lactam moiety and N-linked side *** compounds were derived from multi-step combination of enzymatic and non-enzymatic conversions of intermediates in their biosynthetic ***(2)with an o-phthalaldehyde unit was supposed as the high-reactivity intermediate of phenylspirodrimane lactams via nonenzymatic reaction with *** the present work,an effective and non-enzymatic diversification strategy was developed for the structural diversification of phenylspirodrimane lactams including monomers and dimers from 2 by feeding structurally various mono-and diamines in the fungus Stachybotrys chartarum *** total,24 phenylspirodrimane lactams(1,3-25)including 18 new compounds were *** them,stachybocin A(1),a bioactive phenylspirodrimane lactam dimer,was produced with the yield of 18.7 mg/g of cell dry *** structures of these compounds were elucidated by extensive spectroscopic data,single-crystal X-ray diffraction(Cu Kα),and calculated electronic circular dichroism(ECD)*** revealed that compounds 1,17,and 24 displayed significant inhibitory effect on the inactivated state of hNav 1.2 channels with IC_(50) values of 0.22,2.08,and 0.53μmol/L,*** addition,1 showed potent protein tyrosine phosphatase 1B(PTP1B)inhibitory N-methyl-b-aspartate(NMDA)receptor antagonistic,and anti-inflammatory activities.

关键词： Phenylspirodrimane lactams Stachbotrydial Nonenzymatic reaction hNav 1.2channels inhibitoryactivity Stachybotrys chartarum

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低聚季铵盐对聚驱采出水包油乳状液破乳机理

湖南大学学报（自然科学版） 2016年第6期43卷 117-123页

作者：吴亚陈世军陈刚徐家业西安石油大学化学化工学院陕西西安710065 陕西师范大学化学化工学院陕西西安710062

针对聚驱采出的高含水原油乳状液稳定性强、油水分离困难,采用瓶试法筛选出一类对含聚乳状液油水分离性能极好的破乳剂低聚季铵盐I,当I加量浓度为25mg/L时,55℃破乳进行到60min时,脱水率达96.5%,与常规的聚醚或多胺类破乳剂相比,乳状液... 详细信息

针对聚驱采出的高含水原油乳状液稳定性强、油水分离困难,采用瓶试法筛选出一类对含聚乳状液油水分离性能极好的破乳剂低聚季铵盐I,当I加量浓度为25mg/L时,55℃破乳进行到60min时,脱水率达96.5%,与常规的聚醚或多胺类破乳剂相比,乳状液脱出水色透明澄清,油水界面齐.通过光学显微镜、动态分析仪、接触角测量从微观和宏观分析研究了低聚季铵盐I对乳状液的作用机理.研究表明,相比常规的聚醚或多胺破乳剂,低聚季铵盐I对聚驱采出水包油乳状液油滴聚结速度更快;自由水层在油滴聚结分离区占主导作用的是不稳定机制,低聚季铵盐I使乳状液中油滴发生向上的迁移运动而非絮凝沉降,有利于脱出游离水的分离和水质的提高;接触角测量表明低聚铵盐I使乳状液处理的岩石表面转向水湿状态,对乳化膜的强润湿改变性能导致液膜破裂,油水分离.

关键词：低聚季铵盐水包油乳状液光学显微镜稳定性分析润湿性

genome-wide Association Analyses Reveal the genetic Basis of Stigma Exsertion in Rice

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Molecular Plant 2017年第4期10卷 634-644页

作者： Hao Zhou Pingbo Li WeiboXie Saddam Hussain Yibo Li Duo Xia Hu Zhao Shengyuan Sun junxiao Chen Ho.g ye jun Hou Da Zhao.guanjun gao Qinglu Zhang go.gwei Wang Xingming Lian Jinghua Xiao Sibin Yu Xianghua Li Yuqing He National Key Laboratory of Crop genetic Improvement and National Centre of Plant gene Research (Wuhan) Huazhong Agricultural University Wuhan 430070China

Stigma exsertion, a key determinant of the rice mating system, greatly contributes to the application of heterosis in rice. Altho.gh a few quantitative trait loci associated with stigma exsertion have been fine map- ped or cloned, the underlying genetic architecture remains unclear. We performed a genome-wide associ- ation study on stigma exsertion and related floral traits using 6.5 million SNPs characterized in 533 diverse accessions of oryza sativa. We identified 23 genomic loci that are significantly associated with stigma exsertion and related traits, three of which are co-localized with three major grain size genes gS3, gW5, and gW2. Further analyses indicated that these three genes affected the stigma exsertion by controlling the size and shape of the spikelet and stigma. Combinations of gS3 and gW5 largely defined the levels of stigma exsertion and related traits. Selections of these two.genes resulted in specific distributions of floral traits amo.g subpopulations of o. sativa. The low stigma exsertion combination gw5gS3 existed in half of the cultivated rice varieties; therefore, introducing the gW5gs3 combination into male sterile lines is of high potential for improving the seed production of hybrid rice.

关键词： stigma exsertion gWAS hybrid seed production floral traits grain shape rice

铁基合金基底热喷涂热障涂层的界面化合物演化

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材料热处理学报 2015年第10期36卷 181-186页

作者：韩玉君叶福兴李晓泉南京工程学院材料工程学院江苏南京211167 江苏省先进结构材料与应用技术重点实验室江苏南京211167 天津大学材料科学与工程学院天津市现代连接技术重点实验室天津300072

分别用超音速氧燃料工艺和大气等离子工艺在球墨铸铁QT-500上制备热障涂层的粘结层与陶瓷层。通过X射线衍射仪、扫描电子显微镜和Cr3+荧光光谱表征热障涂层随着高温氧化服役进行界面化合物演变规律。研究表明,热障涂层的粘结层/陶瓷层... 详细信息

分别用超音速氧燃料工艺和大气等离子工艺在球墨铸铁QT-500上制备热障涂层的粘结层与陶瓷层。通过X射线衍射仪、扫描电子显微镜和Cr3+荧光光谱表征热障涂层随着高温氧化服役进行界面化合物演变规律。研究表明,热障涂层的粘结层/陶瓷层界面上层(CS层)由(Co,Ni)(Co,Al)2o4和Co3o4组成,其下层为Al2o3;用面积法分析了CS层和Al2o3层厚度的变化规律;粘结层/基底合金界面的热生长氧化物为层状和块状交替分布的形貌,其成分主要为Al2o3。1050℃+15 h高温氧化后,粘结层/陶瓷层界面残余压应力随θ-Al2o3→α-Al2o3相转变完全达最低值,然后其残余压应力略有升高,这与大量生长的Co3o4和尖晶石类氧化物有关。

关键词：超音速氧燃料工艺热障涂层 Cr3+荧光光谱 CS层高温氧化

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正二十面体金刚石的形成及其计算机模拟

新型炭材料 2009年第2期24卷 102-108页

作者：余志明魏秋平叶浚 A. Flodrstrom 中南大学材料科学与工程学院湖南长沙410083 粉末冶金国家重点实验室湖南长沙410083 Royal Institute of Technology Vahallavagen 79SE-10044StockholmSweden

采用热丝化学气相沉积(HFCVD)法,以甲烷和氢气为反应气体,在Yg13(WC1-3%Co)硬质合金基体上制备了金刚石膜。膜中存在大量五重对称结构的正二十面体金刚石晶粒(IDC)。当尺寸较小时晶粒为较完整的正二十面体形状,尺寸达微米级后晶粒为带有... 详细信息

采用热丝化学气相沉积(HFCVD)法,以甲烷和氢气为反应气体,在Yg13(WC1-3%Co)硬质合金基体上制备了金刚石膜。膜中存在大量五重对称结构的正二十面体金刚石晶粒(IDC)。当尺寸较小时晶粒为较完整的正二十面体形状,尺寸达微米级后晶粒为带有"沟槽"或"凹坑"的变种正二十面体形状。研究了IDC的形成机制,并进行了计算机模拟。结果表明:对于四面体立方结构来说,IDC的{111}孪晶面与正常{111}孪晶面相比存在2.87o的差异,孪晶面两侧原子几何位置失配,使其成为畸变孪晶面,这种畸变孪晶面导致IDC晶粒存在"凹坑"和"沟槽";IDC的晶核是正十二面体烷(C20H20)。

关键词：化学气相沉积金刚石正二十面体晶粒十二面体烷计算机模拟