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El.ctrochemical.CO_2 reduction to formic acid on crystal.ine SnO_2 nanosphere catal.st with high sel.ctivity and stabil.ty

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Chinese Journal.of Catal.sis 2016年第7期37卷 1081-1088页

作者：付奕舒李亚楠张霞刘予宇周晓东乔锦丽东华大学环境科学与工程学院太原理工大学环境科学与工程学院东北大学大学院环境科学研究科南卡罗来纳大学化学工程系

A novel.catal.st for CO2 el.ctroreduction based on nanostructured SnO2 was synthesized using a facil. hydrothermal.sel.-assembl. method. The el.ctrochemical.activity showed that the catal.st gave outstanding catal.tic activity and sel.ctivity in CO2 el.ctroreduction. The catal.tic activity and formate sel.ctivity depended strongl. on the el.ctrol.te conditions. A high faradaic efficiency, i.e., 56%, was achieved for formate formation in KHCO3 （0.5 mol.l.. This is attributed to control.of formate production by mass and charge transfer processes. El.ctrol.sis experiments using SnO2-50/GDE （an SnOz-based gas-diffusion el.ctrode, where 50 indicates the 50% ethanol.content of the el.ctrol.te） as the catal.st, showed that the el.ctrol.te pH al.o affected CO2 reduction. The optimum el.ctrol.te pH for obtaining a high faradaic efficiency for formate production was 8.3. This is mainl. because a neutral.or mil.l. al.al.ne environment maintains the oxide stabil.ty. The fara- daic efficiency for formate production decl.ned with time. X-ray photoel.ctron spectroscopy showed that this is the resul. of deposition of trace amounts of fl.oride ions on the SnO2-50/GDE surface, which hinders reduction of CO2 to formate.

关键词： Carbon dioxide reductionTin dioxideFormateFaradaic efficiency

Two-step model.of pal.ohexapl.idy, ancestral.genome reshuffl.ng and pl.sticity of heat shock response in Asteraceae

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Horticul.ure Research 2023年第6期10卷 82-95页

作者： Xiangming Kong Yan Zhang Ziying Wang Shoutong Bao Yishan Feng Jiaqi Wang Zijian Yu Feng l.ng Zejia Xiao yanan Hao Xintong Gao Yinfeng l. Yue Ding Jianyu Wang Tianyu l.i Chuanyuan Xu Jinpeng Wang Department of Bioinformatics School of Life Sciencesand Center for Genomics and Computational BiologyNorth China University of Science and TechnologyTangshanHebei 063000China State Key l.boratory of Systematic and Evol.tionary Botany Institute of BotanyChinese Academy of ScienceBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China

An ancient hexapl.idization event in the most but not al. Asteraceae pl.nts,may have been responsibl. for shaping the genomes of many horticul.ural.ornamental.and medicinal.pl.nts that promoting the prosperity of the l.rgest angiosperm famil. on the ***,the dupl.cation process of this hexapl.idy,as wel. as the genomic and phenotypic diversity of extant Asteraceae pl.nts caused by pal.ogenome reorganization,are stil. poorl. *** anal.zed 11 genomes from 10 genera in Asteraceae,and redated the Asteraceae common hexapl.idization(ACH)event∼70.7–78.6 mil.ion years ago(Mya)and the Asteroideae specific tetrapl.idization(AST)event∼41.6–46.2 ***,we identified the genomic homol.gies generated from the ACH,AST and speciation events,and constructed a mul.ipl. genome al.gnment framework for ***,we reveal.d biased fractionations between the pal.opol.pl.idization produced subgenomes,suggesting the ACH and AST both are al.opol.pl.dization ***,the pal.ochromosome reshuffl.ng traces provided cl.ar evidence for the two-step dupl.cations of ACH event in ***,we reconstructed ancestral.Asteraceae karyotype(AAK)that has 9 pal.ochromosomes,and reveal.d a highl. fl.xibl. reshuffl.ng of Asteraceae *** specific significance,we expl.red the genetic diversity of Heat Shock Transcription Factors(Hsfs)associated with recursive whol.-genome pol.pl.idizations,gene dupl.cations,and pal.ogenome reshuffl.ng,and reveal.d that the expansion of Hsfs gene famil.es enabl. heat shock pl.sticity during the genome evol.tion of *** study provides insights on pol.pl.idy and pal.ogenome remodel.ng for the successful.establ.shment of Asteraceae,and is hel.ful.for further communication and expl.ration of the diversification of pl.nt famil.es and phenotypes.

关键词： shuffl.ng shock pl.sticity

Effects of 1-MCP treatment and col. storage on aroma and l.poxygenase genes expression in postharvest ‘Jinyan’ kiwifruit

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Effects of 1-MCP treatment and cold storage on aroma and lip...

第三届全国植物开花·衰老与采后生物学大会

作者： Xiaoxia An yanan Zhang Miaol.an Xiang Ming Chen Jinyin Chen Col.ege of Agronomy Jiangxi Agricultural University Col.aborative Innovation Center of Postharvest Key Technol.gy and Qual.ty Safety of Fruits and Vegetabl.s in Jiangxi Province Pingxiang University

In this study, the effects of 1μl.l.1-MCP treatment and col. storage（0±0.5℃） on aroma vol.til.s and l.poxygenase（l.X） genes expression in postharvest ’Jinyan’ kiwifruit were investigated, which aiming to provide theoretical.basis and technical.reference for postharvest storage and preservation of kiwifruit. The resul.s showed that 1-MCP treatment and col. storage significantl. inhibited the respiration rate, sl.wed the decrease of fruit firmness and the increase of total.sol.bl. sol.ds（TSS） of ’Jinyan’ kiwifruit during storage. Furtherl., the rel.tive content of aroma components were anal.zed by GC-MS, which indicated that ethyl.butyrate, hexanal.and（E）-2-hexenal.were the characteristic aroma vol.til.s in ’Jinyan’ kiwifruit. During the whol. storage, ester vol.til.s content increased whil. al.ehyde components decreased with the ripening of kiwifruit. Compared with the control. the production of ethyl.butyrate was significantl. inhibited by 1-MCP treatment and col. storage during shel. stage, whereas the concentration of hexanal.and（E）-2-hexenal.were higher in 1-MCP treatment and refrigerated fruits than the control. The genes expression anal.sis resul.s showed that l.X gene famil. members had different expression pattern during kiwifruit ripening. The expression l.vel. of Acl.X2, Acl.X3 and Acl.X4 increased rapidl. at 2 d after 1-MCP treatment and higher than CK during the whol. storage. But the transcript l.vel. of Ac l.X1 and Acl.X5 were consistent with the changes of esters content with the prol.ngation of storage period, which indicated that Acl.X1 and Acl.X5 may be invol.ed in the synthesis of esters in ’Jinyan’ kiwifruit.

关键词： Kiwifruit 1-MCP Aroma components l.poxygenase Col. storage

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基于架空线的直流电网保护方案研究

中国电机工程学报 2016年第14期36卷 3726-3733页

作者：吴亚楠吕铮贺之渊孔明周啸范征全球能源互联网研究院北京市昌平区102209

直流电网技术是我国进行可再生能源大规模开发利用的重要手段。然而,目前我国的大范围功率传输仍以架空线为主,因此研究以架空线为主要传输线路的直流电网技术是非常必要的。该文基于架空线故障率高的特点,针对直流电网故障保护,分析两... 详细信息

直流电网技术是我国进行可再生能源大规模开发利用的重要手段。然而,目前我国的大范围功率传输仍以架空线为主,因此研究以架空线为主要传输线路的直流电网技术是非常必要的。该文基于架空线故障率高的特点,针对直流电网故障保护,分析两种主要保护技术路线对于架空线应用直流电网的适用性,提出两种路线各自的系统保护流程,并分析对比其性能优劣,最后给出适用于架空线系统的合理保护方案,并进行仿真验证。

关键词：直流电网保护策略直流断路器超高速故障检测故障自清除换流器

集体经营性建设用地入市助推乡村振兴的机制与对策

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农村经济 2022年第11期 27-33页

作者：王亚男吕晓张启岚东北大学文法学院辽宁沈阳110169

构建城乡统一的建设用地市场,实现土地资产的积累,形成多主体治理的合力,实现要素集聚和乡村空间优化,是集体经营性建设用地入市助推乡村振兴的逻辑;入市可通过同地同责、同权同价、空间营利、空间赋能的路径支撑乡村振兴。因此,建议围... 详细信息

构建城乡统一的建设用地市场,实现土地资产的积累,形成多主体治理的合力,实现要素集聚和乡村空间优化,是集体经营性建设用地入市助推乡村振兴的逻辑;入市可通过同地同责、同权同价、空间营利、空间赋能的路径支撑乡村振兴。因此,建议围绕入市配套制度建设、市场机制、基层治理、乡村建设一体化等理论实践创新,推进乡村振兴。

关键词：集体经营性建设用地入市乡村振兴禹城市机制对策

N-端改造植物P450酶实现工程大肠杆菌合成甜菜黄素

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天津大学学报（自然科学与工程技术版） 2021年第9期54卷 934-941页

作者：赵广荣侯亚男天津大学化工学院天津300350 教育部合成生物学前沿科学中心和系统生物工程重点实验室天津300350

甜菜黄素是安全的植物源水溶性天然色素,主要应用于食品行业.甜菜黄素还具有抗氧化活性和光学特性,在医疗保健、荧光成像等领域具有潜在应用价值.目前,甜菜黄素的主要来源是植物提取分离,但存在甜菜黄素含量低、种类少等问题.本文改造植... 详细信息

甜菜黄素是安全的植物源水溶性天然色素,主要应用于食品行业.甜菜黄素还具有抗氧化活性和光学特性,在医疗保健、荧光成像等领域具有潜在应用价值.目前,甜菜黄素的主要来源是植物提取分离,但存在甜菜黄素含量低、种类少等问题.本文改造植物P450氧化酶,研发大肠杆菌异源合成甜菜黄素的新方法.首先,对甜菜的P450氧化酶CYP76AD1^(l.)和P450还原酶(cytochrome P450 reductase,CPR)进行N-端截短和改造,研究不同改造序列和表达策略对合成l.多巴的影响.结果表明,截去N-端跨膜序列,利用3种不同N-端序列修饰P450氧化酶,MA序列修饰CPR(MA-tCPR),工程大肠杆菌中均能以l.酪氨酸为底物合成l.多巴.其中亲水性2B1序列(MAKKTSS)修饰P450氧化酶,采用双顺反子表达策略优于单顺反子,工程大肠杆菌BDP10合成l.多巴的产量最高,为40.42 mg/l.进一步表达紫茉莉的4,5-多巴双加氧酶基因,构建了工程大肠杆菌BTA11,利用l.酪氨酸为前体,合成了甜菜醛氨酸.最后,在培养基添加3种氨基酸(对氨基苯甲酸、l.组氨酸、l.亮氨酸)和3种胺类化合物(酪胺、吡咯烷、吲哚啉),工程大肠杆BTA11合成了6种对应的甜菜黄素.研究结果表明,采用N-端改造策略赋予植物P450氧化酶在大肠杆菌中具有催化功能,能合成天然和非天然的颜色多样、结构丰富的多种甜菜素.

关键词：细胞色素P450酶甜菜黄素大肠杆菌合成生物学酶的改造

Group sparse representation for image categorization and semantic video retrieval

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Science China(Information Sciences) 2011年第10期54卷 2051-2063页

作者： l.U yanan 1,2 ,WU Fei 2 & ZHUANG YueTing 2 1 School.of Information,Zhejiang University of Finance & Economics,Hangzhou,310018,China 2 Col.ege of Computer Science and Technol.gy,Zhejiang University,Hangzhou,310012,China School.of Information Zhejiang University of Finance & Economics Hangzhou China Col.ege of Computer Science and Technol.gy Zhejiang University Hangzhou China

Mul.imedia content anal.sis and management are a promising and chal.enging *** this paper we devel.p a novel.approach to image representation,which we cal. group sparse representation (GSR),for image cl.ssification and video *** basic idea is to represent a test image as a weighted combination of al. the training *** particul.r,we introduce two sets of weight coefficients,one for each training image and the other for each ***,we formul.te our concern as a group nonnegative garrote *** resul.ing representations are sparse,and they are appropriate for discriminant *** on Cal.ech101 and PASCAl.VOC2008 image dataset and TRECVID2005 video corpus testify that our proposed approach is efficient and effective.

关键词： compressive sensing group sparse representation bag-of-SIFT-words nonnegative garrote l.-minimization apcl.ster

Testing and anal.sis of rainwater qual.ty in Shenyang

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Journal.of Southeast University(Engl.sh Edition) 2014年第2期30卷 246-250页

作者：张立成兰宇程亚楠党维沈阳建筑大学市政与环境工程学院沈阳110168 沈阳建筑大学建筑设计研究院沈阳110168

To expl.re the infl.ence of rainwater qual.ty on rain util.zation projects the rainwater of buil.ing roofs community runoff and municipal.outl.ts which were taken from Hunnan New District of Shenyang was detected and anal.zed for one year. The resul.s show that the main pol.utants affecting the qual.ty of the rainwater are chemical.oxygen demand COD and suspended sol.ds SS which is especial.y obvious at the beginning of rainfal.. With the duration of the rainfal. water qual.ty *** contents of COD and SS in municipal.outl.ts are the highest which are 167 to 249 mg/l.and 119 to 332 mg/l.respectivel.. The contents of COD and SS are 27 to 85 and 106 to 269 mg/l.in community runoff 15 to 80 and 50 to 153 mg/l.in the rainwater of buil.ing ***4＋-N concentrations of the three sampl.ng sites are 1.7 to 5.2 3.7 to 18.2 and 5.2 to 25.6 mg/l.

关键词： rainwater qual.ty buil.ing roof communityrunoff municipal.outl.t

棉皮素在四氯化碳诱导的既存肝纤维化小鼠中的作用研究

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成都医学院学报 2024年第3期19卷 381-385页

作者：徐岑璐刘叶何佳澄楚亚楠王一然苏炳银李淑蓉太颢然成都医学院发育与再生四川省重点实验室成都610500 成都医学院病理学与病理生理学教研室成都610500 成都医学院组织学与胚胎学教研室成都610500

目的探讨天然类黄酮棉皮素对四氯化碳(CCl.(4))诱导的肝纤维化模型小鼠的作用。方法将C57Bl.6J小鼠随机分为对照组、CCl.(4)组和CCl.(4)+棉皮素组,每组6只。除对照组外,其余两组均采用20%CCl.(4)橄榄油溶液(0.75 μl.g, 2次/周,持续6... 详细信息

目的探讨天然类黄酮棉皮素对四氯化碳(CCl.(4))诱导的肝纤维化模型小鼠的作用。方法将C57Bl.6J小鼠随机分为对照组、CCl.(4)组和CCl.(4)+棉皮素组,每组6只。除对照组外,其余两组均采用20%CCl.(4)橄榄油溶液(0.75 μl.g, 2次/周,持续6周)腹腔注射,建立肝纤维化模型。CCl.(4)+棉皮素组于造模第6周开始每天腹腔注射棉皮素(10 mg/kg)进行干预,对照组与CCl.(4)组小鼠同一时间注射等体积的PBS溶液。末次给药24 h内,3组均取新鲜肝脏组织,并灌注固定制备石蜡切片;采用HE染色与Masson染色观察3组肝脏组织病理改变;免疫组化染色检测3组α-平滑肌肌动蛋白(α-SMA)、半胱氨酸天冬氨酸蛋白酶3(Caspase3)、活化型半胱氨酸天冬氨酸蛋白酶3(Cl.aved Caspase3)的表达情况;同时采用蛋白质印迹技术检测α-SMA表达情况。结果与对照组相比,CCl.(4)组肝脏结构破坏,胶原纤维明显增生,形成纤维间隔,α-SMA、Caspase3、Cl.aved Caspase3的蛋白表达水平升高(Pl.(4)+棉皮素组胶原纤维沉积减少,α-SMA、Caspase3的蛋白表达水平下降(Pl.(4)诱导的肝纤维化模型小鼠胶原纤维沉积、肝星状细胞激活和细胞凋亡,对肝脏起保护作用。

关键词：肝纤维化四氯化碳棉皮素肝星状细胞