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Photocatalytic Carboxylation of Phenyl Halides with CO_(2) by Metal-Organic Frameworks Materials

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Chinese Journal of Chemistry 2021年第2期39卷 312-316页

作者： Lina Su Yin Zhang xueying qiu Jianyu Han Zhiyong Tang CAS Key Laboratory for Nanosystem and Hierarchy Fabrication CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology Beijing100190 China School of Future Technology University of Chinese Academy of SciencesBeijing100049 China School of Materials Science and Engineering Harbin Institute of TechnologyHarbinHeilongjiang150080 China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing100049 China

In this work,important commercial pharmaceutical intermediates,phenylpropionic acid compounds,are successfully obtained by catalyzing the reaction of carbon dioxide with phenyl halides using MOF-5,a typical metal-organic framework(MOF)*** influence of temperature,pressure,catalyst type and light on the reaction is investigated,and a 90.3%selectivity towards fluorophenylpropionic acid is ***,the catalysts are effective for varied benzyl compounds containing different substituent *** catalysts are stable and remain active after three cycles.

关键词： Metal-organic frameworks Photocatalysis Carbon dioxide fixation Heterogeneous catalysis Ibruprofen

Remarkably Enhanced Hydrogen Oxidation Reaction Activity of Carbon-supported Pt by Facile Nickel Modification

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Chemical Research in Chinese Universities 2020年第1期36卷 105-109页

作者： HUANG Xuewei LONG Chang HAN Jianyu ZHANG Jing qiu xueying TANG Zhiyong College of Chemistry Zhengzhou UniversityZhengzhou 450001P.R.China CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190P.R.China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150080P.R.China Institute of Applied Chemistry Shanxi UniversityTaiyuan 030006P.R.China

Developing high activity catalysts for hydrogen oxidation reaction(HOR)under alkaline condition remains a challenge in the exchange membrane fuel cell(AEMFC).Herein,we report that the activity of carbon-supported platinum(Pt/C)towards the hydrogen oxidation reaction(HOR)in alkaline media can be remarkably enhanced by simple immersion of Pt/C in nickel chloride *** adsorption of hydrogen on the catalyst surface is weakened by modification of *** HOR activity on the Pt/C after immersion possesses an excellent mass current density of 33.4 A/gmetal,which is 18%higher than that(28.3 A/gmetal)on Pt/C.

关键词： Electrocatalyst Hydrogen oxidation Pt/C Modified nickel

Structure regulated catalytic performance of gold nanocluster-MOF nanocomposites

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Nano Research 2020年第7期13卷 1928-1932页

作者： Yanfei Zhu xueying qiu Shenlong Zhao Jun Guo Xiaofei Zhang Wenshi Zhao Yanan Shi Zhiyong Tang CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Chemical and Biomolecular Engineering The University of SydneySydneyNSW 2006Australia School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150080China

Atomically precise gold(Au)nanoclusters(NCs)as visible light photosensitizers supported on the substrate for photoredox catalysis have attracted considerable ***,eficient control of their photocatalytic activity and long-term stability is still ***,we report a coordination-assisted self-assembly strategy in combination with electrostatic interaction to sandwich Au2:(Capt)18(abbreviated as AU25,Capt=captopril)NCs between an inner core and an outer shell made of UiO-66,denoted as UiO-66@Au25@***,the sandwich-like nanocomposite displays significantly enhanced catalytic activity along with an excellent stability when used in the selective photocatalytic aerobic oxidation of sulfide to *** comparison,AU25 NCs simply located at the outer surface or insider matrix of UiO-66(short as Au2/UiO-66 and AU2s@UiO-66)show poor stability and low conversion,*** structure regulated difference in the catalytic performances of three nanocomposites is assigned to the varied distribution of active sites(Au NCs)in metal-organic frameworks(MOFs).This work offers the opportunity for application of nanoclusters in catalysis,energy conversion and even biology.

关键词： Au nanoclusters metal-organic frameworks photocatalysis singlet oxygen sulfoxidation

Optical Activity of Chiral Metal Nanoclusters

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Accounts of Materials Research 2021年第1期2卷 21-35页

作者： Yanfei Zhu Jun Guo xueying qiu Shenlong Zhao Zhiyong Tang CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China The University of Sydney School of Chemical and Biomolecular EngineeringSydneyNSW 2006Australia

CONSPECTUS:The emerging chirality in nanomaterials represents one of the most dynamic areas in modern *** many novel chiral nanomaterials have been reported,the origin of their chirality and related optical activity have been not unveiled *** to the fast development of noble metal cluster chemistry,the structures of many chiral nanoclusters(CNCs)have been precisely determined and their chirality origin has been decoded as four different levels including chiral ligand,helix staple motif,asymmetry metal kernel,and chiral arrangement of organic ***,the strong optical activity associated with the electron transitions of the noble metal core is popularly reported among CNCs protected by chiral ligands,following the so-called“outside-in”chirality transfer theory,namely,from organic ligand to metal ***,inherent chiral structures are discerned inside CNCs consisting of achiral ligands,such as the helix staples found in Au38(SR)24 and Au102(SR)44(SR=thiolate)and the chiral metal kernel existing in Au20(PP3)4Cl4(PP3=tris(2-(diphenylphosphino)ethyl)phosphine).These chiral nanostructures induce distinct optical activity and even present reversed chirality transformation in the case of Au38(SR)24(i.e.,from chiral core structure to organic ligand).In the past decade,our group has carried out extensive research work on preparation,enantioseparation,optical activity,and application of chiral inorganic *** representatives,enantiopure right-handed and left-handed Au20(PP3)4Cl4 clusters of intrinsic kernel chirality were acquired through an innovative supramolecular self-assembly method and their circular dichroism(CD)feature involving only the metal core was systematically studied;Au3[R/S-Tol-BINAP]3Cl(R/S-Tol-BINAP:R/S-2,2′-bis(di-p-tolylphosphino)-1,1′-binaphthyl)clusters with the smallest metal-atom number among the reported CNCs were designed and synthesized by using the privileged chiral Tol-BINAP ligand,wh

关键词： chiral circular kernel

Facile synthesis of ultrathin metal-organic framework nanosheets for Lewis acid catalysis

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Nano Research 2019年第2期12卷 437-440页

作者： Xiaofei Zhang Lin Chang Zhongjie Yang Yanan Shi Chang Long Jianyu Han Binhao Zhang xueying qiu Guodong Li Zhiyong Tang School of Materials Science and Engineering Harbin Institute of Technology Harbin 150080 China CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology Beijing 100190 China

Ultrathin metalorganic framework (MOF) nanosheets are attracting great interest in catalysis due to their unique and intriguing two-dime nsional (2D) features. Although many progresses have been achieved, it is still highly desirable to develop novel strategies for controllable synthesis of the well-defined ultrathin MOF nanosheets. Herein we report a polyvinylpyrrolidone (PVP)-assisted route to synthesize the ultrathin Ni-MOF nanosheets characteristic of 1.5 nm in thickness, in which PVP is reacted with 2-aminoterephthalic acid (H2BDC-NH2) via formation of C=N bon d, followed by coord inatio n with Ni2+ io ns to form the ultrathi n MOF n anosheets. Impressively, when used in the Kno eve nagel condensation reactions of propane dinitrile with different aldehydes, ultrathin Ni-MOF nanosheets display the significantly enhanced catalytic activity and good stability in respect with the bulk Ni-MOF, mainly owing to the exposed active sites as well as facile mass transfer and diffusion of substrates and products.

关键词： ultrathin nanosheet metal-organic framework Lewis acid site Knoevenagel condensation

Single site catalyst with enzyme-mimic micro-environment for electroreduction of CO_(2)

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Nano Research 2022年第3期15卷 1817-1823页

作者： Chang Long Kaiwei Wan xueying qiu Xiaofei Zhang Jianyu Han Pengfei An Zhongjie Yang Xiang Li Jun Guo Xinghua Shi Hui Wang Zhiyong Tang Shaoqin Liu School of Materials Science and Engineering MOE Key Laboratory of Micro-systems and Micro-structures ManufacturingHarbin Institute of TechnologyHarbin150080China CAS key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing100190China University of Chinese Academy of Sciences Beijing100049China Institute of High Energy Physics CAS Beijing100049China

Single site catalysts provide a unique platform for mimicking natural enzyme due to their tunable interaction between metal center and coordinated ***,most works have focused on preparing structural and functional models of nature enzyme,with less reports also taking the local chemical environment,i.e.,functional/catalytic residues around the active site which is an essential feature of enzymes,into ***,we report a Co-centered porphyrinic polymer containing the enzyme-mimic micro-environment,where the linker triazole over CoN4 site enables formation of hydrogen bond with the*COOH intermediate,thus promoting the electrocatalytic reduction of CO_(2).As-prepared catalyst achieves the CO_(2)-to-CO conversion of 5,788 h^(−1) turnover frequency value and near unit(~96%)faradaic efficiency at−0.61 V versus reversible hydrogen *** strategy will bring new dimension of designing highly active single-site catalysts.

关键词： single-site catalyst CO_(2)electroreduction enzyme-mimic

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饮用水水源地安全评价指标的分析

中国水利 2009年第21期 25-28页

作者：曹小欢邱雪莹黄茁水利部长江水利委员会长江科学院武汉430010 武汉大学资源与环境科学学院武汉430072

水源地是生产、生活用水的初始环节,水源地水质和安全保障直接关系到用水安全和经济社会的可持续发展。通过比较国内外水质指标,分析水源地水质的潜在威胁因素,结合水质指标的发展趋势,引入了饮用水水源地安全风险指标,提出了构建饮用... 详细信息

水源地是生产、生活用水的初始环节,水源地水质和安全保障直接关系到用水安全和经济社会的可持续发展。通过比较国内外水质指标,分析水源地水质的潜在威胁因素,结合水质指标的发展趋势,引入了饮用水水源地安全风险指标,提出了构建饮用水水源地安全评价指标体系的新思路。

关键词：水源地评价指标风险评价水安全

流域综合管理改革的观点分异研究——以长江流域为例

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人民长江 2012年第11期43卷 99-102页

作者：邱雪莹杨小柳徐健北京大学城市与环境学院北京100871

流域管理面临种种挑战,而流域综合管理成为了当前研究的热点。为了辨识长江流域综合管理改革中可能出现的问题,以水利部、省主管部门、长江水利委员会3个行政层面为研究对象,着眼改革的内容、策略、方向和方案,采用社会学的调查法,收集... 详细信息

流域管理面临种种挑战,而流域综合管理成为了当前研究的热点。为了辨识长江流域综合管理改革中可能出现的问题,以水利部、省主管部门、长江水利委员会3个行政层面为研究对象,着眼改革的内容、策略、方向和方案,采用社会学的调查法,收集3个层面的原始信息,以认知率、满意率、认可率等指标衡量和分析层面间的差异。结果表明:在大多数涉及改革的问题上,行政层面间存在明显的观点分异。该研究方法可丰富改革的决策依据,值得深入探讨。

关键词：流域综合管理研究方法管理改革长江流域

基于铁死亡相关蛋白探讨化瘀祛痰方对高脂合并肝癌小鼠的影响及机制

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中华中医药学刊 2021年第9期39卷 137-141,I0027页

作者：裘雪莹贾连群宋囡王群辽宁中医药大学研究生学院辽宁沈阳110847 辽宁中医药大学中医脏象理论及应用教育部重点实验室辽宁沈阳110847

目的探讨化瘀祛痰方防治肝癌的可能有效机制。方法将Balb/c小鼠随机分为空白组、肝癌组、模型组、化瘀祛痰方低剂量组、化瘀祛痰方中剂量组和化瘀祛痰方高剂量组,每组8只。空白组和肝癌组予普通饲料喂养,其余各组予高脂饲料喂养;除空白... 详细信息

目的探讨化瘀祛痰方防治肝癌的可能有效机制。方法将Balb/c小鼠随机分为空白组、肝癌组、模型组、化瘀祛痰方低剂量组、化瘀祛痰方中剂量组和化瘀祛痰方高剂量组,每组8只。空白组和肝癌组予普通饲料喂养,其余各组予高脂饲料喂养;除空白组以外其余各组采用H22肝癌细胞原位注射的方法建立肝癌模型。于第12周开始,化瘀祛痰方低、中、高剂量组分别给予化瘀祛痰方7.6、15.2、30.4 g/kg灌胃,空白组、肝癌组及模型组给予相应体积的生理盐水灌胃。各组灌胃4周后,检测血清甘油三酯(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、肝细胞活性氧簇(ROS)、还原性谷胱甘肽(GSH)水平,肝脏铁死亡相关因子p53、谷胱甘肽过氧化物酶4(GPX4)、胱氨酸/谷氨酸反向转运体(xCT)蛋白及mRNA表达;观察肝脏组织形态学改变。结果与空白组相比,模型组小鼠血清TC、TG、 LDL-C含量显著升高,HDL-C含量显著降低(P<0.01);肝癌组和模型组小鼠肝脏组织内ROS水平显著增高,GSH水平显著下降(P<0.01),肝脏组织p53蛋白及mRNA的表达增高,GPX4、xCT蛋白和mRNA水平显著降低(P<0.05或P<0.01);HE染色显示肝细胞肿胀明显且胞浆内含有大量脂肪空泡蓄积,且模型组的病理作用效果比肝癌组更显著(P<0.05或P<0.01)。与模型组比,化瘀祛痰低、中、高剂量组小鼠血清TC、TG和LDL-C水平显著降低,HDL-C含量显著升高;肝脏组织内ROS水平显著下降,GSH水平显著升高(P<0.01);p53蛋白及mRNA的表达降低,GPX4、xCT蛋白和mRNA水平显著升高(P<0.05或P<0.01);肝细胞形态恢复或者部分恢复,胞浆内脂滴含量明显减少。结论化瘀祛痰方可能通过调控p53/xCT/GPX4通路影响肝细胞铁死亡,减轻肝脏脂质过氧化损伤,从而防治肝癌。

关键词：铁死亡原发性肝癌高脂化瘀祛痰方脂质过氧化