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Efficient light-driven reductive amination of furfural to furfurylamine over ruthenium-cluster catalyst

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Journal of Energy Chemistry 2023年第1期76卷 239-248,I0007页

作者： Zhen Xue Shasha Wu yujing fu Lan Luo Min Li Zhenhua Li Mingfei Shao Lirong Zheng Ming Xu Haohong Duan State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Department of Chemistry TsinghuaUniversityBeijing 10084China Institute of High Energy Physics The Chinese Academy of SciencesBeijing 100049China

Selective reductive amination of carbonyl compounds with high activity is very essential for the chemical and pharmaceutical industry,but scarcely successful paradigm was reported via efficient photocatalytic reactions.Herein,the ultrasmall Ru nanoclusters(~0.9 nm)were successfully fabricated over P25 support with positive charged Ru^(δ+)species at the interface.A new route was developed to achieve the furfural(FAL)to furfurylamine(FAM)by coupling the light-driven reductive amination and hydrogen transfer of ethanol over this type catalyst.Strikingly,the photocatalytic activity and selectivity are strongly dependent on the particle size and electronic structure of Ruthenium.The Ru^(δ+)species at the interface promote the formation of active imine intermediates;moreover,the Ru nanoclusters facilitate the separation efficiency of electrons and holes as well as accelerate the further hydrogenation of imine intermediates to product primary amines.In contrast Ru particles in larger nanometer size facilitate the formation of the furfuryl alcohol and excessive hydrogenation products.In addition,the coupling byproducts can be effectively inhibited via the construction of sub-nanocluster.This study offers a new path to produce the primary amines from biomass-derived carbonyl compounds over hybrid semiconductor/metal-clusters photocatalyst via light-driven tandem catalytic process.

关键词： furfural Reductive amination Ru nanoclusters Hydrogen transfer Photocatalysis

Co-thermal in-situ reduction of inorganic carbonates to reduce carbon-dioxide emission

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Science China Chemistry 2023年第4期66卷 1201-1210页

作者： Zhen Xue Jingyi Guo Shasha Wu Wenfu Xie yujing fu Xiaojie Zhao Kui Fan Ming Xu Hong Yan Mingfei Shao Xue Duan State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

Thermal decomposition of inorganic metal carbonates is the main path to prepare metal oxides;nonetheless,it is always accompanied by the emission of large amounts of CO_(2) as one of the gas products.This study reports a concept of co-thermal insitu reduction of inorganic carbonates by using the energy released by carbonate decomposition under pure hydrogen atmosphere,which reduces the decarboxylation temperature and significantly inhibits the CO_(2) emissions.A combination of hydrogen–deuterium exchange,isotope experiment,and density functional theory calculations demonstrates that the CO results from the selective cleavage of Ca–O bonds at the surface of CaCO_(3) via the direct hydrogenation mechanism at relatively low temperature.However,it undergoes the reverse water–gas shift reaction path at high temperature,i.e.,CO being produced by the reduction of CO_(2) released by the decomposition of carbonates.This study sheds light on the potential of green hydrogen technology for inorganic carbonate valorization toward high value-added products,which can facilitate the large-scale industrial applications.

关键词： inorganic carbonate co-thermal in-situ reduction carbon dioxide emission reduction carbon monoxide

基于可视化热重分析技术的宣纸热分解特性研究及动力学分析

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复旦学报（自然科学版） 2024年第1期63卷 95-105,I0001页

作者：陈彪付小航谭静卢郁静丁延伟中国科学技术大学科技史与科技考古系安徽合肥230026 中国科学技术大学合肥微尺度物质科学国家研究中心安徽合肥230026

为了解宣纸的劣化机理,本文利用可视化热重分析技术对宣纸在氮气与空气中的热分解过程进行了实验和分析,结果表明其过程主要阶段为发挥性成分的析出过程,宣纸样品经历快速失重、面积收缩且颜色加深,其中空气气氛可促进热分解反应并在反... 详细信息

为了解宣纸的劣化机理,本文利用可视化热重分析技术对宣纸在氮气与空气中的热分解过程进行了实验和分析,结果表明其过程主要阶段为发挥性成分的析出过程,宣纸样品经历快速失重、面积收缩且颜色加深,其中空气气氛可促进热分解反应并在反应后期氧化前期生成的炭化物;然后以高斯分布函数对微商热重(DTG)曲线进行拟合得到三组分,并且三组分的反应区间符合生物质的热分解特性且受气氛影响;此外,本文还基于Lab色彩空间对实时观察热分解图像进行了分析,其结果相比热失重数据在反应起始和中止阶段灵敏度更高,并可对热失重数据进行补充;同时,本文以Friedman法、FWO法计算宣纸在氮气与空气中的表观活化能E,得到氮气与空气气氛中的结果分别为195.4kJ/mol、162.98kJ/mol;最后通过Malek法对宣纸样品的热分解数据进行最概然机理函数的选择,并得到氮气中的热分解活化能E为245.60kJ/mol,指前因子的自然对数lnA为37.39s^(-1);空气中活化能E在150.18~305.41kJ/mol,lnA在49.13~20.18s^(-1)。

关键词：色度分析动力学活化能反应机理函数

闫慧敏运用调理气机法分型论治儿童胸闷变异性哮喘经验

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中医杂志 2024年第10期65卷 1001-1004页

作者：符瑜静刘畅郝静李亚男闫慧敏(指导) 首都医科大学附属北京儿童医院北京西城100045 首都医科大学

总结闫慧敏教授运用调理气机法分型论治儿童胸闷变异性哮喘的临证经验。认为儿童胸闷变异性哮喘病位主要在肺,涉及肝、脾,核心病机为气机不利。临证以调理气机为基础分型进行辨治:肺气虚寒、痰饮内伏证,治宜补肺益气、温化痰饮,常用玉... 详细信息

总结闫慧敏教授运用调理气机法分型论治儿童胸闷变异性哮喘的临证经验。认为儿童胸闷变异性哮喘病位主要在肺,涉及肝、脾,核心病机为气机不利。临证以调理气机为基础分型进行辨治:肺气虚寒、痰饮内伏证,治宜补肺益气、温化痰饮,常用玉屏风散合小青龙汤加减;痰气郁结证,治宜疏肝解郁、化痰散结,常用半夏厚朴汤合金铃子散加减;气虚血瘀证,治宜补虚扶正、行气活血,常用血府逐瘀汤加减。治疗过程应把握疾病发展动态,分型论治,尤其注重气机变化。

关键词：胸闷变异性哮喘气机名医经验闫慧敏

杜仲汤对去卵巢大鼠骨质疏松症的影响及机制研究

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中药新药与临床药理 2024年第4期35卷 461-468页

作者：罗兰兰张宇静任明诗傅芸瑛陈泽彬陈明刘波江西中医药大学药学院江西南昌330004 江西省中医药管理局中药防治老年性疾病重点研究室江西南昌330004 南昌大学第一附属医院骨科医院江西南昌330006

目的探讨杜仲汤对去卵巢大鼠骨质疏松症的影响及机制。方法将42只雌性SD大鼠随机分为假手术组、模型组、阳性药组(戊酸雌二醇,0.09 mg·kg^(-1))、谷胱甘肽组(36 mg·kg^(-1))以及杜仲汤低、中、高剂量组(0.54、1.08、2.16 g·kg^(-1))... 详细信息

目的探讨杜仲汤对去卵巢大鼠骨质疏松症的影响及机制。方法将42只雌性SD大鼠随机分为假手术组、模型组、阳性药组(戊酸雌二醇,0.09 mg·kg^(-1))、谷胱甘肽组(36 mg·kg^(-1))以及杜仲汤低、中、高剂量组(0.54、1.08、2.16 g·kg^(-1))。去卵巢模型大鼠复制成功后,按照设定剂量灌胃给药,灌胃体积为10 mL·kg^(-1),每日1次,连续给药200 d。采用生化试剂盒检测大鼠血清中谷胱甘肽过氧化物酶(GSH)含量;ELISA法检测大鼠血清中抗酒石酸酸性磷酸酶(TRACP)、骨保护素(OPG)含量;骨密度仪检测大鼠股骨骨密度;HE染色法观察大鼠胫骨组织病理变化;Western Blot法检测骨组织中骨形态发生蛋白2(BMP-2)、OPG、一型胶原(COL1)蛋白表达水平;RT-PCR法检测骨组织中BMP-2、Runt相关转录因子2(RUNX2)mRNA表达水平。结果与假手术组比较,模型组大鼠体质量增长值显著升高(P<0.01);血清GSH、OPG的水平显著降低(P<0.05,P<0.01),TRACP水平显著升高(P<0.01);骨密度明显降低(P<0.05);骨小梁结构不完整,出现明显断裂,小梁数稀疏且明显变薄;骨组织中BMP-2、OPG、COL1蛋白表达水平均显著下降(P<0.01),BMP-2、RUNX2mRNA表达水平明显降低(P<0.05)。与模型组比较,杜仲汤低、中、高剂量组大鼠体质量增长值均显著降低(P<0.05,P<0.01),血清GSH水平显著升高(P<0.01),骨小梁结构明显改善,骨小梁变粗,数量增加,骨组织中BMP-2、RUNX2 mRNA表达水平均显著升高(P<0.01);杜仲汤中剂量组大鼠的血清OPG水平显著升高(P<0.01);杜仲汤低剂量组大鼠的血清TRACP水平显著降低(P<0.01),骨组织中COL1蛋白表达水平明显升高(P<0.05);杜仲汤低、中剂量组大鼠的骨密度显著升高(P<0.01),骨组织中OPG蛋白表达水平明显升高(P<0.01);杜仲汤中、高剂量组大鼠骨组织中BMP-2蛋白表达水平明显升高(P<0.05)。结论杜仲汤能提高去卵巢大鼠的骨密度,保护骨小梁完整性,对去卵巢大鼠骨质疏松症有一定防治作用,其机制可能与提高血清GSH、OPG水平,降低TRACP水平,上调BMP-2、OPG、COL1蛋白以及BMP-2、RUNX2mRNA表达,从而促进骨形成有关。

关键词：骨质疏松症杜仲汤去卵巢大鼠氧化应激骨形成

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苏云金芽胞杆菌Cry毒素的研究现状

中国农学通报 2024年第5期40卷 88-96页

作者：符百文许炼郑梅霞朱育菁福建省农业科学院作物研究所(福建省种质资源中心) 福州350013

苏云金芽胞杆菌是应用最为成功的微生物杀虫剂,它产生的最大一类杀虫蛋白是Cry毒素,其田间应用是防治农业害虫和提高作物产量的重要手段。Cry毒素具有针对宿主生物速效、对非目标生物的影响低、对环境友好和可降解等优势。本研究简述了... 详细信息

苏云金芽胞杆菌是应用最为成功的微生物杀虫剂,它产生的最大一类杀虫蛋白是Cry毒素,其田间应用是防治农业害虫和提高作物产量的重要手段。Cry毒素具有针对宿主生物速效、对非目标生物的影响低、对环境友好和可降解等优势。本研究简述了Cry毒素在投入农业使用中产生的昆虫抗性问题,归纳了Cry毒素结构和功能、作用机制、蛋白结构域、昆虫抗性等研究现状,总结了表观遗传机制、受体调控、原生肠道菌群促进抗性的三大特点,分析了对抗性昆虫的应对措施,认为人工选择新型耐药昆虫以预见可能的耐药途径、Cry毒素进行定向进化和田间交互使用策略是研究重点。本文旨在为Cry毒素在农业生物防治中的成功应用提供理论依据。

关键词：生物防治 Cry毒素昆虫抗性杀虫机制突变改造

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可视化热重分析技术对宣纸热分解形态的研究

中国测试 2024年第6期50卷 62-69页

作者：谭静韩媛付小航卢郁静朱玥玮狄雨萌陈彪丁延伟中国科学技术大学科技史与科技考古系安徽合肥230026 中国科学技术大学合肥微尺度物质科学国家研究中心安徽合肥230026

为研究宣纸形态在受热过程中的实时变化特征,使用高清摄像系统原位记录宣纸样品在氮气和空气中热分解的图像序列,并结合红外光谱测试宣纸在不同温度时对应的结构状态以分析相关热解过程。结果表明,宣纸在氮气热分解中颜色逐渐变黑,直径... 详细信息

为研究宣纸形态在受热过程中的实时变化特征,使用高清摄像系统原位记录宣纸样品在氮气和空气中热分解的图像序列,并结合红外光谱测试宣纸在不同温度时对应的结构状态以分析相关热解过程。结果表明,宣纸在氮气热分解中颜色逐渐变黑,直径尺寸随着温度增加而减小,这与宣纸纤维逐渐降解炭化有关;在空气热分解中,宣纸颜色出现先黑后白的现象,是由炭化物在空气中氧化分解引起。亮度变化率(ΔL)和收缩率(Δd)可量化宣纸形态在热分解过程中的变化程度,其亮度约在150℃后逐渐降低,在氮气热分解中最终下降62.2%,尺寸收缩25.0%;在空气热分解中,宣纸的亮度下降63.2%后开始回升最终高于初始亮度,其尺寸收缩了50%。宣纸的颜色变化与内部纤维的热分解程度密切相关,将ΔL与热解转化率(α)进行回归分析,两者存在指数量化关系。基于所得指数模型,可根据宣纸的ΔL计算α值,进一步无损评估宣纸老化后其内部纤维组分的降解情况,为珍贵纸张的老化研究提供参考。

关键词：宣纸热分解形态可视化量化分析老化评估

Morphological characteristics of Neoseiulus setarius Ma,Meng&Fan,sp.nov.(Acari:Phytoseiidae)from China

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Zoological Systematics 2023年第2期48卷 169-176页

作者： Min Ma Yu Liu yujing Li Xiaotong fu Qinghai Fan Ruixia Meng College of Plant Protection Shanxi Agriculture UniversityTaiguChina College of Horticulture and Plant Protection Inner Mongolia Agriculture UniversityHohhot 010018China Plant Health&Environment Laboratory Ministry for Primary IndustriesAuckland 1072New Zealand

The genus Neoseiulus Hughes,1948 is one of the largest genera in Phytoseiidae and contains more than 364 valid species in the world.In this paper,a new species N.setarius Ma,Meng&Fan,sp.***.is described based on both adult female and male specimens collected from Setaria viridis(L.)Beauv.(Gramineae),in Inner Mongolia of China.The adult females of the new species are characterized by having a fully reticulated dorsal shield,barbed Z5,bellshaped spermathecal calyx with a short basal stalk.furthermore,seta R1 is off dorsal idiosomal shield in adult males.

关键词： Mesostigmata taxonomy paraki species subgroup predatory mite

Arabidopsis SYP121 acts as an ROP2 effector in the regulation of root hair tip growth

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Molecular Plant 2022年第6期15卷 1008-1023页

作者： Xiankui Cui Shuwei Wang Yaohui Huang Xuening Ding Zirong Wang Lidan Zheng yujing Bi Fanghui Ge Lei Zhu Ming Yuan Shaul Yalovsky Ying fu State Key Laboratory of Plant Physiology and Biochemistry College of Biological SciencesChina Agricultural UniversityBeijing 100193China Joint Laboratory for International Cooperation in Crop Molecular Breeding Ministry of EducationChina Agricultural UniversityBeijing 100193China Department of Plant Sciences Tel Aviv UniversityTel Aviv 69978Israel

Tip growth is an extreme form of polarized cell expansion that occurs in all eukaryotic kingdoms to generate highly elongated tubular cells with specialized functions, including fungal hyphae, animal neurons, plant pollen tubes, and root hairs (RHs). RHs are tubular structures that protrude from the root epidermis to facilitate water and nutrient uptake, microbial interactions, and plant anchorage. RH tip growth requires polarized vesicle targeting and active exocytosis at apical growth sites. However, how apical exocytosis is spatially and temporally controlled during tip growth remains elusive. Here, we report that the Qa-Soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) SYP121 acts as an effector of Rho of Plants 2 (ROP2), mediating the regulation of RH tip growth. We show that active ROP2 promotes SYP121 targeting to the apical plasma membrane. Moreover, ROP2 directly interacts with SYP121 and promotes the interaction between SYP121 and the R-SNARE VAMP722 to form a SNARE complex, probably by facilitating the release of the Sec1/Munc18 protein SEC11, which suppresses the function of SYP121. Thus, the ROP2-SYP121 pathway facilitates exocytic trafficking during RH tip growth. Our study uncovers a direct link between an ROP GTPase and vesicular trafficking and a new mechanism for the control of apical exocytosis, whereby ROP GTPase signaling spatially regulates SNARE complex assembly and the polar distribution of a Q-SNARE.

关键词： ROP GTPase SYP121 SNARE protein exocytosis root hair tip growth