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Qualitative and quantitative analysis of Brønsted and Lewis acid sites in zeolites:A combined probe-assisted 1H MAS NMR and NH3-TPD investigation

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结构化学 2024年第4期43卷 24-30页

作者： Runze Liu Yankai Bian weili dai School of Materials Science and Engineering & National Institute for Advanced Materials Nankai UniversityTianjin300350PR China

Zeolite is one of the most important heterogeneous catalysts in acid catalytic *** that the catalytic behaviors of zeolites are mostly related to their acidic characteristics,extensive attention has been attracted to the measurements of acid type,strength and concentration in *** techniques including Fourier-transform infrared(FTIR)spectroscopy,probe-assisted 1H,13C and 31P magic angle spinning nuclear magnetic resonance spectroscopy(MAS NMR)as well as temperature programmed desorption of ammonia(NH3-TPD)have been developed for determining the acid ***,a single approach is defective to characterize the acid sites ***,combining the probe-assisted(e.g.,NH3 and CD3CN)1H MAS NMR and NH3-TPD,the acid sites in different zeolites including the acid type,density and strength were *** commonly utilized NH3-TPD to determine the acid strength of zeolite samples with different topologies should be rigorously considered owing to zeolite confinement *** the desorption temperature of NH3 probe molecules,the acid type(Le.,Brønsted acid sites(BAS)and Lewis acid sites(LAS))and the corresponding density could be determined by NH3 probe-assisted 1H MAS NMR spectroscopy,while the acid strength could be investigated via CD3CN probe-assisted 1H MAS NMR spectroscopy.

关键词： ^(1)H MAS NMR NH_(3)-TPD BAS LAS Zeolites

Catalytic upgrading biomass-derived ethanol and acetic acid into C4 chemicals

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Science China Chemistry 2024年

作者： Tingting Yan Mengting Zhang Runzhi Yuan weili dai College of Science Civil Aviation University of China School of Materials Science and Engineering & National Institute for Advanced Materials Nankai University

Synthesis of value-added chemicals from biomass is an essential strategy to mitigate the global dependency on fossil resources and achieve the aim of carbon neutrality. Thereinto, ethanol and acetic acid are crucial biomass-derived platform ***, catalytic upgrading ethanol and acetic acid into C4 energy-intensive fuels and chemicals via the elongation of carbon backbone has received widespread attention. The primary focus of this review is to systematically describe the recent breakthrough in the conversion of ethanol or acetic acid to C4 chemicals including 1,3-butadiene, n-butenes, isobutene or *** attentions will be given to heterogeneous catalyst design strategies, reaction parameters on the catalytic performance along with the relevant mechanism investigations, as well as their future challenges and opportunities. The present review will provide the detailed insights into the synthesis of C4 chemicals from biomass-derived ethanol and acetic acid and shed a light on the development of highly efficient catalysts.

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专业核心课程体验对拔尖学生学习收获的影响机制研究——基于学习性投入的视角

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江苏高教 2024年第9期 73-79页

作者：戴薇郦吴立保王骥南京信息工程大学管理工程学院南京210044 南京信息工程大学高等教育研究所南京210044 南京信息工程大学教师发展与教学评估中心南京210044

专业核心课程是影响拔尖学生学习发展的关键因素,在拔尖创新人才培养的过程中发挥着重要作用。基于学习性投入的视角,对4所高校958名参与“拔尖计划2.0”的学生展开调查,构建课程体验、学习性投入与学习收获的路径模型图。文章建议在“... 详细信息

专业核心课程是影响拔尖学生学习发展的关键因素,在拔尖创新人才培养的过程中发挥着重要作用。基于学习性投入的视角,对4所高校958名参与“拔尖计划2.0”的学生展开调查,构建课程体验、学习性投入与学习收获的路径模型图。文章建议在“拔尖计划”专业核心课程建设中,打破固有课程结构局限性,构建个性化专业核心课程体系;推行“以学生为中心”的教学改革,发挥小班化教学优势,利用研讨课程促进拔尖学生高阶能力提升;充分利用人工智能等信息技术手段,为拔尖学生打造专业核心课程学习新环境。

关键词：拔尖创新人才课程体验学习性投入

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成像装置外设收音设备产业及专利技术分析

河南科技 2024年第7期51卷 133-136页

作者：戴维理国家知识产权局专利局专利审查协作四川中心四川成都610213

【目的】应用场景需求的不断提高,使得人们对成像设备的收音效果提出了更高的要求,有必要对成像装置外设收音设备进行相关探究。【方法】通过不同收音方式外设设备对应的市场主体及相关申请人两条线,对相关产业的专利布局进行分析,对相... 详细信息

【目的】应用场景需求的不断提高,使得人们对成像设备的收音效果提出了更高的要求,有必要对成像装置外设收音设备进行相关探究。【方法】通过不同收音方式外设设备对应的市场主体及相关申请人两条线,对相关产业的专利布局进行分析,对相关产业中的重点主题进行专利技术演进分析。【结果】相关领域的重要申请主体和产业主体均以国外企业为主。【结论】外国成像装置生产商在相关产业中存在明显先发优势。

关键词：成像设备收音产业分析专利分析

恶性肿瘤患者经外周静脉穿刺的中心静脉导管相关性血栓的影响因素及预防措施研究进展

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中国肿瘤临床与康复 2024年第2期31卷 106-113页

作者：田江雪戴维莉张淑香国家癌症中心、国家肿瘤临床医学研究中心、中国医学科学院北京协和医学院肿瘤医院内科北京100021

恶性肿瘤患者留置经外周静脉穿刺的中心静脉导管(PICC)治疗时,常常面临着PICC相关性血栓的风险。文章旨在总结和分析现有文献,探讨恶性肿瘤患者PICC相关性血栓的高危因素及预防措施,为医务人员提供参考和指导,以期降低恶性肿瘤患者发生P... 详细信息

恶性肿瘤患者留置经外周静脉穿刺的中心静脉导管(PICC)治疗时,常常面临着PICC相关性血栓的风险。文章旨在总结和分析现有文献,探讨恶性肿瘤患者PICC相关性血栓的高危因素及预防措施,为医务人员提供参考和指导,以期降低恶性肿瘤患者发生PICC相关性血栓的风险,减少相关并发症并保障治疗顺利完成。

关键词：恶性肿瘤经外周静脉穿刺的中心静脉导管导管相关性血栓影响因素预防措施

Catalytic Hydration of Aromatic Alkynes to Ketones over H-MFI Zeolites

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Chemical Research in Chinese Universities 2022年第1期38卷 173-180页

作者： ZHANG Yunzhe dai weili WU Guangjun GUAN Naijia LI Landong School of Materials Science and Engineering Nankai UniversityTianjin 300350P.R.China

The hydration of alkyne represents the most straightforward and simplest route toward the synthesis of ketone. Herein, Brønsted acidic zeolites are explored as potential catalysts for the liquid-phase phenylacetylene hydration. The topology structure and Si/Al ratio are disclosed to be key factors controlling the catalytic activity of zeolites. Typically, H-MFI zeolite with a Si/Al molar ratio of 13 exhibits the highest catalytic activity, with turnover frequency of 6.0 h-1 at 363 K. Besides, H-MFI zeolite shows good catalytic stability and recyclability in the reaction of phenylacetylene hydration, and the substrate scope can be simply extended to other soluble aromatic alkynes. The reaction mechanism of phenylacetylene hydration is investigated by means of kinetic and spectroscopic analyses. The Markovnikov electrophilic addition of phenylacetylene by hydrated protons is established as the rate-determining step, followed by deprotonation and enol isomerization to derive acetophenone product.

关键词： Phenylacetylene Catalytic hydration Zeolite Brønsted acid site H-MFI

Multifunctional heteroatom zeolites:construction and applications

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Frontiers of Chemical Science and Engineering 2021年第6期15卷 1462-1486页

作者： Qifeng Lei Chang Wang weili dai Guangjun Wu Naijia Guan Landong Li School of Materials Science and Engineering&National Institute for Advanced Materials Nankai UniversityTianjin300350China Key Laboratory of Advanced Energy Materials Chemistry of the Ministry of Education Nankai UniversityTianjin300071China

Multifunctional heteroatom zeolites have drawn broad attentions due to the possible synergistic effects in the catalytic *** achievements have been made on the synthesis,characterization and catalytic applications of multifunctional heteroatom zeolite,while a review on this important topic is still ***,current research status of multifunctional heteroatom zeolites is briefly summarized,aiming to boost further ***,the synthesis strategies toward heteroatom zeolites are introduced,including the direct synthesis and postsynthesis routes;then,the spectroscopic techniques to identify the existing states of heteroatom sites and the corresponding physiochemical properties are shown and compared;finally,the catalytic applications of multifunctional heteroatom zeolites in various chemical reactions,especially in one-step tandem reactions,are discussed.

关键词： zeolite multifunctional active sites heteroatom characterization catalysis

Cationic organobismuth complex as an effective catalyst for conversion of CO_(2) into cyclic carbonates

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Frontiers of Environmental Science & Engineering 2009年第1期3卷 32-37页

作者： Xiaowen ZHANG weili dai Shuangfeng YIN Shenglian LUO Chak-Tong AU College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082China Department of Chemistry Hong Kong Baptist UniversityKowloon TongHong KongChina

In order to achieve high-efficiency conversion of CO_(2) into valuable chemicals,and to exploit new applications of organobismuth compounds,cationic organobismuth complex with 5,6,7,12-tetrahydrodibenz[c,f][1,5]azabismocine framework was examined for the first time for the coupling of CO_(2) into cyclic carbonates,using terminal epoxides as substrates and tetrabutylammonium halide as co-catalyst in a solvent-free environment under mild *** is shown that the catalyst exhibited high activity and selectivity for the coupling reaction of CO_(2) with a wide range of terminal *** selectivity of propylene carbonates could reach 100%,and the maximum turnover frequency was up to 10740 h^(-1) at 120℃ and 3 MPa CO_(2) pressure when tetrabutylammonium iodide was used as ***,the catalyst is environment friendly,resistant to air and water,and can be readily reused and recycled without any loss of activity,demonstrating a potential in industrial application.

关键词： cationic organobismuth complex terminal epoxide carbon dioxide coupling cyclic carbonate

Solvothermal Synthesis and Photocatalytic Performance of Bi_2S_3 Hierarchical Nanostructure

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Journal of Wuhan University of Technology(Materials Science) 2017年第3期32卷 562-567页

作者：伍水生 WANG Jun JIA Qingming dai weili WANG Yaming College of Chemistry and Chemical Engineering Hunan Institute of Engineering Faculty of Chemical Engineering Kunming University of Science and Technology Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resource Recycle Nanchang Hangkong University

The synthesis of Bi2S3 hierarchical nanostructure was reported by a solvothermal reaction using ethylene disulfhydrate as the sulfur source and chelating reagent. The as-synthesized samples were characterized by X-ray diffraction（XRD）, Raman, X-ray photoelectron spectroscopy（XPS）, scanning electron microscopy（SEM） and photoluminescence（PL）. The XRD, Raman, and XPS data confirmed that the as-synthesized sample belongs to orthorhombic phase Bi2S3. The SEM observations displayed that Bi2S3 hierarchical nanostructure assembled from nanorods. A 410 nm ultraviolet photoluminescence（PL） emission of as-synthesized Bi2S3 was observed when the sample was excited with wavelength of 320-330 nm. The Bi2S3 hierarchical nanostructure also shows a significant enhancement of photocatalytic capability toward degrading methyl orange（MO） under UV light, the photodegradation of MO reaches 95% within 180 min.

关键词： nanostructures chemical synthesis luminescence catalytic properties