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Combining anodic alcohol oxidative coupling for C-C bond formation with cathodic ammonia production

National Science Review 2024年第5期11卷 217-226页

作者： Leitao Xu Wei Chen cairong wang Wenjie Wu Yelin Yao Zhifeng Huang Jingcheng Wu Ming Yang Yandong Wu Dianke Xie Yuqin Zou Shuangyin wang State Key Laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringAdvanced Catalytic Engineering Research Center of the Ministry of Education Hunan University

Electrocatalytic oxidation of alcohols using heterogeneous catalysts is a promising aqueous, energy-efficient and environmentally friendly approach, especially for coupling different alcohols to prolong the carbon chain via co-oxidation. Precisely regulating critical steps to tailor electrode materials and electrolyte composition is key to selectively coupling alcohols for targeted synthesis. However, selectively coupling different alcohols remains challenging due to the lack of effective catalyst and electrolyte design promoting specific pathways. Herein, we demonstrate a paired electrolysis strategy for combining anodic oxidative coupling of ethanol（EtOH） and benzyl alcohol（PhCH2OH） to synthesize cinnamaldehyde（CAL） and cathodic ammonia production. The strategies involve:（i） utilizing the salt-out effect to balance selective oxidation and coupling rates;（ii） developing platinum-loaded nickel hydroxide electrocatalysts to accelerate intermediate coupling kinetics;（iii） introducing thermodynamically favorable nitrate reduction at the cathode to improve coupling selectivity by avoiding hydrogenation of products while generating valuable ammonia instead of hydrogen. We achieved 85% coupling selectivity and 278 μmol/h NH3productive rate at 100 m A/cm2with a low energy input（～1.63 V）. The membrane-free, low energy, scalable approach with a wide substrate scope highlights promising applications of this methodology. This work advances heterogeneous electrocatalytic synthesis through rational design principles that integrate anodic oxidative coupling with cathodic nitrate reduction reactions, having synergistic effects on efficiency and selectivity.

关键词： anodic alcohol oxidative coupling C–C bond formation cinnamaldehyde cathodic ammonia production

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Electro-oxidation cross-coupling of primary and secondary alcohols by constructing intermediate-enriched micro-environment

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Science China Chemistry 2023年第8期66卷 2408-2415页

作者： Leitao Xu cairong wang Yelin Yao Wei Chen Zhonghuan Zhu Jingcheng Wu Ming Yang Yandong Wu Shuangyin wang Yuqin Zou State Key Laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangshaHunan410082China School of Chemistry and Chemical Engineering Jishou UniversityJishou416000China

Electrocatalytic dehydrogenative cross-coupling of various alcohols in aqueous electrolytes functionalizes alcohols to form structurally diverse long-carbon-chain ***,it remains challenging to achieve the high selectivity because of the high reactivity of involved carbonyl intermediates and different oxidation rates for the ***,the synthesis ofα,β-unsaturated ketones from alcohols was realized by the electro-oxidation cross-coupling in aqueous solutions by a“salting-out”strategy to engineer the micro-environment at electrocatalytic reaction *** calculations and electrochemical measurements demonstrated that concentrated local intermediates could inhibit the over-oxidation of alcohols and accelerate the coupling reaction kinetics between the *** strategy can couple primary and secondary alcohols to formα,β-unsaturated carbonyl compounds with a selectivity of 87% and be easily scaled up to gram *** study provides an attractive strategy for broadening the diversity of organic products in electrocatalysis.

关键词： electro-oxidation of alcohols cross-coupling cation effect microenvironment

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TEE monitoring for RA-horizontal paradoxical arterial air embolism during sitting-position surgery

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Science China(Life Sciences) 2010年第12期53卷 1405-1409页

作者： YE Xin MA Ting wang TianLong GE MingFei wang cairong GAO Jing LI XiaoHui Department of Anesthesiology Beijing Xuanwu HospitalCapital Medical UniversityBeijing 100053China Department of Cardiology Beijing Xuanwu HospitalCapital Medical UniversityBeijing 100053China

A 36-year-old woman suffered meningioma in her right cerebellopontine *** embolisms often complicate sitting-position *** TEE guides the localization of central venous catheters and promptly locates air embolisms prom... 详细信息

关键词： anesthesia sitting-position surgery transesophageal echocardiography central venous catheter localization venous air embolism

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Genomic analysis of Nypa fruticans elucidates its intertidal adaptations and early palm evolution

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Journal of Integrative Plant Biology 2024年第4期66卷 824-843页

作者： Weihong Wu Xiao Feng Nan wang Shao Shao Min Liu Fa Si Linhao Chen Chuanfeng Jin Shaohua Xu Zixiao Guo cairong Zhong Suhua Shi Ziwen He State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources School of Life SciencesSun Yat-sen UniversityGuangzhou 510275China Greater Bay Area Institute of Precision Medicine School of Life SciencesFudan UniversityGuangzhou 511462China Hainan Academy of Forestry(Hainan Academy of Mangrove) Haikou 571100China

Nypa fruticans(Wurmb),a mangrove palm species with origins dating back to the Late Cretaceous period,is a unique species for investigating long-term adaptation strategies to intertidal environments and the early evolution of ***,we present a chromosome-level genome sequence and assembly for *** integrated the genomes of *** and other palm family members for a comparative genomic analysis,which confirmed that the common ancestor of all palms experienced a whole-genome duplication event around 89 million years ago,shaping the distinctive characteristics observed in this *** also inferred a low mutation rate for the *** genome,which underwent strong purifying selection and evolved slowly,thus contributing to its stability over a long evolutionary ***,ancient duplicates were preferentially retained,with critical genes having experienced positive selection,enhancing waterlogging tolerance in ***,we discovered that the pseudogenization of Early Methionine-labelled 1(EM1)and EM6 in *** underly its crypto-vivipary characteristics,reflecting its intertidal *** study provides valuable genomic insights into the evolutionary history,genome stability,and adaptive evolution of the mangrove *** results also shed light on the long-term adaptation of this species and contribute to our understanding of the evolutionary dynamics in the palm family.

关键词： crypto-vivipary genome stability long-term adaptation mangrove Nypa fruticans palm

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二尖瓣腱索断裂的超声诊断及病因病理分析

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中国超声医学杂志 2000年第6期16卷 41-43页

作者：王彩荣刘强首都医科大学宣武医院B超室

目的 :探讨二尖瓣腱索断裂的彩超特征和病因病理改变。方法 :对彩色多普勒超声心动图诊断的 14例二尖瓣腱索断裂患者的超声资料、病因及其中 6例病理进行分析。结果 :( 1)二尖瓣腱索断裂的二维超声显示前、后叶腱索断裂比例 1∶ 1,均为... 详细信息

目的 :探讨二尖瓣腱索断裂的彩超特征和病因病理改变。方法 :对彩色多普勒超声心动图诊断的 14例二尖瓣腱索断裂患者的超声资料、病因及其中 6例病理进行分析。结果 :( 1)二尖瓣腱索断裂的二维超声显示前、后叶腱索断裂比例 1∶ 1,均为二级以上腱索部分或全部断裂 ,瓣尖完全不能合拢 ,形成连枷样改变。M型表现 :左心房室扩大。 5例左室流出道增宽 ,11例可见二尖瓣前叶或后叶扑动。 CDFI依断裂的腱索瓣叶不同彩色返流的方向不同。 ( 2 )二尖瓣腱索断裂的病因多样 ,13例有心脏病基础。见于风湿性心脏病、二尖瓣脱垂、冠心病、高心病、甲亢性心脏病及心包肿瘤患者。 ( 3)二尖瓣的纤维组织增生、粘液样变性是造成二尖瓣腱索断裂的主要病理改变。结论 :二尖瓣腱索断裂多有心脏病基础 ,彩超不但可以明确心脏病的性质、腱索断裂的部位、程度 ,也可以判断返流的方向和程度 ,具有其它检查方法不可比拟的优越性

关键词：二尖瓣腱索断裂超声心动图诊断

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ADSORPTION OF PHENOL IN NON-AQUEOUS SYSTEM BASED ON HYDROGEN-BONDING

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Chinese Journal of Reactive Polymers 2000年第1期9卷 17-22页

作者： XU Mancai wang cairong SHI Zuoqing XU Mingcheng ZHANG Shang LI Haitao FAN Yunge HE Binglin Department ofChemistry Hunan Normal UniversityChangsha 410081China The State Key Lab of Functional Polymeric Materials for Adsorption and Separation Institute of Polymer Chemistry Nankai UniversityTianjin 300071China

Two hydrogen-bonding adsorbents-macroporous crosslinked poly(p-nitrostyrene) and poly(p-vinylbenzyl amide)--were synthesized, and the absorption property of phenol from cyclohexane solution onto the adsorbents was studied. The differential adsorption heats for varied adsorption capacities calculated from the adsorption isotherms according to the Clapeyron-Clausius equation lay in the range of hydrogen bond energy (8-50kJ/mol). The adsorption capacity of o-nitrophenol in cyclohexane was much less than that of phenol under the same condition. The adsorption capacity of phenol from cyclohexane onto polyacrylonitile was much less than that onto poly(p-nitrostyrene) or poly(p-vinylbenzyl amide). All these results revealed that adsorption of phenol from cyclohexane by poly(p-nitrostyrene) or poly(p-vinylbenzyl amide) is based on hydrogen-bonding.

关键词： Hydrogen-bonding adsorbent. Poly(p-nitrostyrene). Poly(p-vinylbenzyl amide) Phenol. Adsorption

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一种吡啶酰胺类配体与Tb(Ⅲ)配位模式的探讨

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化学通报 2019年第2期82卷 179-182,98页

作者：王彩荣王璟琳长治学院化学系长治046011

研究了Tb(Ⅲ)对配体N,N-二(2-羧基苯基)-2,6-吡啶二甲酰胺(BCPD)的乙醇溶液的荧光滴定光谱,结果发现滴定过程中两者之间可能存在两种结合模式[(BCPD)_2Tb和(BCPD) Tb]。通过进一步研究配体BCPD的荧光发射光谱和时间扫描荧光分析Tb(Ⅲ)... 详细信息

研究了Tb(Ⅲ)对配体N,N-二(2-羧基苯基)-2,6-吡啶二甲酰胺(BCPD)的乙醇溶液的荧光滴定光谱,结果发现滴定过程中两者之间可能存在两种结合模式[(BCPD)_2Tb和(BCPD) Tb]。通过进一步研究配体BCPD的荧光发射光谱和时间扫描荧光分析Tb(Ⅲ)的特征光谱,从不同角度证明了两种不同配位模式的存在并分析了原因。研究结果进一步丰富和完善了稀土有机配合物的配位理论,对荧光材料的制备具有一定指导意义。

关键词： N,N-二(2-羧基苯基)-2 6-吡啶二甲酰胺 Tb(Ⅲ) 配位模式

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ADSORPTION OF TANNIN FROM AQUEOUS SOLUTION ONTO MACROPOROUS CROSSLINKED POLY(N-VINYL-ACETAMIDE) VIA HYDROGEN BONDING

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Chinese Journal of Reactive Polymers 2000年第1期9卷 23-28页

作者： XU Mancai wang cairong XU Mingcheng SHI Zuoqing ZHANG Shang LI Haitao SHI Rongfu FAN Yunge HE Binglin Department of Chemistry Hunan Normal UniversityChangsha 410081China The State Key Laboratory of Functional Polymeric Materials for Adsorption and Separation Institute of Polymer ChemistryNankai UniversityTianjin 300071China

A strongly hydrophilic hydrogen-bonding adsorbent-macroporous crosslinked poly(N- vinyl-acetamide). which contain both hydrogen bond acceptor and donator, was synthesized. Adsorption mechanism and dynamic adsorption of tannin from aqueous solution onto the adsorbent were investigated. Most of the differential adsorption heats for various adsorption capacities calculated from the adsorption isotherms according to Clapeyron-Clausius equation lay in the range of hydrogen bond energy (8-50kJ/mol). Adsorption properties of the adsorbent were studied in detail. These results revealed a hydrogen bonding mechanism of the adsorption of tannin from aqueous solution onto the adsorbent. The result of the dynamic adsorption of tanning with the initial concentration under 600 mg/L showed that the adsorption rate of tannin exceeded 90% when the flow rate was 3BV/h and the effluent volume reached 100 BV. Therefore, the developed hydrogen-bonding adsorbent--macroporous crosslinked poly(N-vinyl-acetamide)—is an excellent adsorbent to remove tannin from extract of natural products. and has great value in application.

关键词： Hydrogen-bonding adsorbent. Poly(N-vinyl-acetamide) Tannin Adsorption

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掺杂钆、钇的吡啶二酰胺铕配合物的发光性能

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化学通报 2015年第8期78卷 764-767页

作者：王彩荣王璟琳白洋长治学院化学系长治046011

以N,N'-二(2-羧基苯基)-2,6-吡啶二甲酰胺(BCPD)为配体,按不同摩尔比掺杂Ln3+(Ln=Gd,Y)的Eu混合物为中心体,合成掺杂钆、钇的稀土铕配合物EuxLn1-x-BCPD,并对配合物进行了光谱分析。红外分析结果表明,掺杂钆、钇后的配合物结构与未掺杂... 详细信息

以N,N'-二(2-羧基苯基)-2,6-吡啶二甲酰胺(BCPD)为配体,按不同摩尔比掺杂Ln3+(Ln=Gd,Y)的Eu混合物为中心体,合成掺杂钆、钇的稀土铕配合物EuxLn1-x-BCPD,并对配合物进行了光谱分析。红外分析结果表明,掺杂钆、钇后的配合物结构与未掺杂的BCPD-Eu配合物的配位结构基本保持一致;荧光分析结果表明,两种掺杂离子对铕配合物的特征荧光均存在"共发光效应",但钆的共荧光作用要强于钇;随着掺杂离子的加入,体系中R值均大于1,且当掺杂稀土离子与铕离子的比例接近1∶1时,所得掺杂配合物的荧光强度最大。实验结果为进一步开发成本低且发光性能良好的稀土发光材料提供了依据。

关键词： N,N'-二(2-羧基苯基)-2,6-吡啶二甲酰胺铕配合物掺杂荧光光谱

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多绳摩擦式提升机钢丝绳换绳工艺优化

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煤矿机械 2019年第5期40卷 98-100页

作者：王彩绒徐志强山西晋城无烟煤矿业集团有限责任公司山西晋城048006

针对矿井多绳摩擦式提升机传统换绳工艺过程中存在的工艺复杂、繁琐,高空作业,作业时间长等问题,借助YHC型换绳车和现场测量,确定采用独特工艺的2.2.2换绳法。即收旧绳的同时放新绳,新、旧首绳同步在井口自动对换,并对换绳工艺流程优化... 详细信息

针对矿井多绳摩擦式提升机传统换绳工艺过程中存在的工艺复杂、繁琐,高空作业,作业时间长等问题,借助YHC型换绳车和现场测量,确定采用独特工艺的2.2.2换绳法。即收旧绳的同时放新绳,新、旧首绳同步在井口自动对换,并对换绳工艺流程优化,缩短了换绳时间,提高了安全系数,减少了人员和材料的投入。实践证明,优化后的多绳摩擦式提升机钢丝绳换绳工艺,能有效降低安全生产成本和高空作业危险系数,具有广阔的应用前景。

关键词：多绳摩擦式提升机高空作业换绳车工艺流程

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