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Flammable gases produced by TiO_(2) nanoparticles under magnetic stirring in water

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Friction 2022年第7期10卷 1127-1133页

作者： Pengcheng LI Chongyang TANG Xiangheng XIAO Yanmin JIA wanping chen School of Physics and Technology Wuhan UniversityWuhan 430072China School of Science Xi'an University of Posts and TelecommunicationsXi'an 710054China

The friction between nanomaterials and Teflon magnetic stirring rods has recently drawn much attention for its role in dye degradation by magnetic stirring in *** the friction between TiO_(2) nanoparticles and magnetic stirring rods in water has been deliberately enhanced and *** much as 1.00 g TiO_(2) nanoparticles were dispersed in 50 mL water in 100 mL quartz glass reactor,which got gas-closed with about 50 mL air and a Teflon magnetic stirring rod in *** suspension in the reactor was magnetically stirred in *** gases of 22.00 ppm CO,2.45 ppm CH_(4),and 0.75 ppm H_(2) were surprisingly observed after 50 h of magnetic *** reference,only 1.78 ppm CO,2.17 ppm CH_(4),and 0.33 ppm H_(2) were obtained after the same time of magnetic stirring without TiO_(2) *** magnetic stirring rods were simultaneously employed to further enhance the stirring,and as much as 30.04 ppm CO,2.61 ppm CH_(4),and 8.98 ppm H_(2) were produced after 50 h of magnetic stirring.A mechanism for the catalytic role of TiO_(2) nanoparticles in producing the flammable gases is established,in which mechanical energy is absorbed through friction by TiO_(2) nanoparticles and converted into chemical energy for the reduction of CO_(2) and H_(2)*** finding clearly demonstrates a great potential for nanostructured semiconductors to utilize mechanical energy through friction for the production of flammable gases.

关键词： friction magnetic stirring catalysis CO_(2)reduction TiO_(2)

基于循证理念的护理模式结合同伴支持干预对急性心肌梗死患者自我效能感、生活质量的影响

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中国当代医药 2024年第12期31卷 158-161页

作者：谢杏芳林惠芳陈婉萍广东省广州市荔湾中心医院心血管内科广东广州510170 广东省广州市荔湾中心医院内分泌科广东广州510170

目的探讨基于循证理念的护理模式结合同伴支持干预在急性心肌梗死(AMI)患者中的应用效果。方法选取2021年1月至2022年12月广东省广州市荔湾中心医院收治的172例AMI患者作为研究对象,采用随机数字表法将其分为对照组(86例)和观察组(86例... 详细信息

目的探讨基于循证理念的护理模式结合同伴支持干预在急性心肌梗死(AMI)患者中的应用效果。方法选取2021年1月至2022年12月广东省广州市荔湾中心医院收治的172例AMI患者作为研究对象,采用随机数字表法将其分为对照组(86例)和观察组(86例)。对照组采取常规护理,观察组实施基于循证理念的护理模式结合同伴支持干预,两组均持续护理至患者出院。比较两组护理效果(心理状态、自我效能感、生活质量、护理满意度)。结果观察组护理后抑郁自评量表(SDS)、焦虑自评量表(SAS)评分低于对照组,一般自我效能感量表(GSES)评分高于对照组,差异有统计学意义(P<0.05);观察组护理后健康调查简表(SF-36)各项评分均高于对照组,差异有统计学意义(P<0.05);观察组患者护理满意度评分高于对照组,差异有统计学意义(P<0.05)。结论基于循证理念的护理模式结合同伴支持干预可缓解AMI患者不良情绪,有效提升患者自我效能感,利于生活质量的改善,从而提升患者满意度。

关键词：急性心肌梗死循证理念护理模式同伴支持干预自我效能感生活质量

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原核Argonaute的应用研究进展

华中农业大学学报 2024年第4期43卷 82-93页

作者：王飞李文强刘洋王珑瑜陈晚苹崔佳凯马立新省部共建生物催化与酶工程国家重点实验室/工业生物技术湖北省重点实验室/湖北大学生命科学学院武汉430062

原核生物Argonautes(pAgos)是参与细胞防御外来DNA入侵的可编程核酸酶。在体外,pAgos可以结合小的单链核酸(ssDNA/ssRNA)向导来识别和切割互补DNA/RNA。在体内,pAgos优先靶向多拷贝遗传元件、噬菌体和质粒,从而抑制入侵核酸的扩增和噬... 详细信息

原核生物Argonautes(pAgos)是参与细胞防御外来DNA入侵的可编程核酸酶。在体外,pAgos可以结合小的单链核酸(ssDNA/ssRNA)向导来识别和切割互补DNA/RNA。在体内,pAgos优先靶向多拷贝遗传元件、噬菌体和质粒,从而抑制入侵核酸的扩增和噬菌体感染。pAgos作为一类新兴的可编程核酸酶,比目前应用最为广泛的CRISPR-Cas系统更具灵活性,在生物技术方面展现出巨大的潜力。早期的研究聚焦于嗜热的pAgo,目前基于嗜热pAgos的主要应用包括分子诊断和体外DNA组装。为了推进基于Ago的体内生物技术,如基因编辑的应用,研究人员的焦点逐渐转移到中温生物来源的pAgos,虽然目前pAgos还未实现基因组编辑,但是随着越来越多的pAgo被发掘以及研究人员对pAgos催化机制的深入研究,有望开发基于pAgos的下一代基因编辑技术。本文总结了已知代表性pAgos和基于pAgos发展的生物技术,并简要分析了pAgos在原核生物和真核生物体内应用面临的挑战和可能的应对策略。

关键词：可编程核酸酶原核Argonaute 基因编辑分子诊断 DNA组装

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Boosting tribo-catalytic conversion of H_(2)O and CO_(2)by Co_(3)O_(4)nanoparticles through metallic coatings in reactors

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Journal of Advanced Ceramics 2023年第10期12卷 1833-1843页

作者： Xuchao Jia Hongbo Wang Hua Lei chenyue Mao Xiaodong Cui Yong Liu Yanmin Jia Wenqing Yao wanping chen School of Physics and Technology Wuhan UniversityWuhan 430072China School of Science Xi’an University of Posts and TelecommunicationsXi’an 710061China Department of Chemistry Tsinghua UniversityBeijing 100084China

In recent years,more and more metal oxides have been finding critical tribo-catalytic ***,we have explored the tribo-catalytic conversion of H_(2)O and CO_(2)using Co_(3)O_(4)nanoparticles and obtained some surprising *** an as-received 150 mL glass reactor enclosed with 10 mL of H_(2)O,0.10 g of Co_(3)O_(4)nanoparticles,1 atm of CO_(2),and a Teflon magnetic rotary disk,we observed the production of as much as 57.41μmol/L of H_(2),0.15μmol/L of CH_(4),and 0.21μmol/L of CO after 5 h of magnetic *** coatings of Cu,Ni,SUS316,Ti,Nb,Mo,and W were further introduced on reactor bottoms *** those coatings of Ni,SUS316,Ti,and Nb,the reduction of CO_(2)was dramatically enhanced,and C_(2+)products of C_(2)H_(6)and C_(2)H_(4)were *** for the Ti coating,the amounts of H_(2)and CH_(4)were increased by 2 and 26 times from those for the glass bottom,respectively,and the amounts of C_(2)H_(6)and C_(2)H_(4)were very *** Co_(3)O_(4)nanoparticles were proven chemically stable under magnetic stirring in water,and hydroxyl radicals and superoxide radicals have been detected for the Co_(3)O_(4)nanoparticles under magnetic stirring through fluorescence spectroscopy and electron paramagnetic resonance spectroscopy *** findings not only reveal outstanding capability of Co_(3)O_(4)to generate multicarbon products from H_(2)O and CO_(2)through tribo-catalysis but also highlight a promising potential of tribo-catalysis as a whole to harness mechanical energy for addressing energy shortages and environmental pollution.

关键词： tribo-catalysis water splitting CO_(2)reduction Co_(3)O_(4)

Contrasting room-temperature hydrogen sensing capabilities of Pt-SnO2 and Pt-TiO2 composite nanoceramics

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Nano Research 2016年第11期9卷 3528-3535页

作者： Yao Xiong wanping chen Yesheng Li Ping Cui Shishang Guo Wei chen Zilong Tang Zijie Yan Zhenyu Zhang School of Physics and Technology Wuhan University Wuhan 430072 China School of Materials Science and Engineering State Key Laboratory of New Ceramics and Fine Processing Tsinghua University Beijing 100084 China International Center for Quantum Design of Functional Materials (ICQD) Hefei Laboratory for Physical Sciences at Microscale (HFNL) and Synergetic Innovation Center of Notional Quantum Information and Quantum Physics University of Science and Technology of China Hefei 230026 China Department of Chemical and Biomolecular Engineering Clarkson University Potsdam New York 13699 USA

Contrasting room-temperature hydrogen sensing behaviors have been revealed for Pt-TiO2 and Pt-SnO2 composite nanoceramics. In the case of the Pt-TiO2 nanoceramics, the ultrahigh hydrogen sensitivities are lost abruptly when the oxygen/hydrogen concentration ratio in ambient atmosphere reaches a critical value. However, in the case of the Pt-SnO2 nanoceramics, such a phenomenon does not occur, and the extraordinary room-temperature hydrogen sensing capabilities are observed in the presence of oxygen in air. Our combined experimental and theoretical investigations establish a unified mechanism for both the systems, which is rooted in hydrogen chemisorption on the surface and interstitial lattice sites of SnO2 and TiO2; the difference in stability of the chemisorbed hydrogen on SnO2 and TiO2 is considered responsible for the contrasting hydrogen sensing capabilities. The central findings are helpful in enriching our microscopic understanding of hydrogen interaction with various metal oxide semiconductors （MOSs） at room temperature in varying mixed gaseous concentrations, and they could be instrumental in developing reliable room-temperature hydrogen sensors based on bulk MOSs.

关键词： Sn02 nanoceramics sensors hydrogen room-temperature

催化性室温气体敏感金属氧化物陶瓷的研究进展与挑战

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科学通报 2023年第31期68卷 4195-4209页

作者：宋建楠陈万平武汉大学物理科学与技术学院人工微结构教育部重点实验室武汉430072 武汉大学深圳研究院深圳518057

以金属氧化物半导体厚膜作为气体敏感材料的气体传感器因结构简单、稳定可靠而具有广泛应用,但其200~400℃的工作温度也使其对于易燃易爆气体的检测具有风险,发展室温气体敏感的金属氧化物半导体材料多年来得到了人们的广泛关注.绝大多... 详细信息

以金属氧化物半导体厚膜作为气体敏感材料的气体传感器因结构简单、稳定可靠而具有广泛应用,但其200~400℃的工作温度也使其对于易燃易爆气体的检测具有风险,发展室温气体敏感的金属氧化物半导体材料多年来得到了人们的广泛关注.绝大多数研究都是通过金属氧化物半导体材料的低维纳米化以使其实现室温气体敏感,而本文介绍了一种通过引入催化剂以使金属氧化物半导体实现室温气体敏感,即催化性室温气体敏感的新策略.该策略近10年的实践取得了一系列成果,包括采用SnO_(2)纳米团聚体粉料所制备的高抗湿室温氢气敏感Pt-SnO_(2)复合陶瓷、采用5μm WO_(3)粉料制备的高抗湿室温氢气敏感Pt-WO_(3)复合陶瓷、室温CO敏感Pt-SnO_(2)和Pd-SnO_(2)复合陶瓷、室温NO_(2)敏感Pt-Au-SnO_(2)复合陶瓷.本文也分析了催化性室温气体敏感金属氧化物陶瓷走向应用所面临的主要挑战,即长时间的老化、室温下在H_(2)S中暴露等均可使其室温气体敏感性能出现严重的退化,而短暂温和的热处理(例如200℃10 min)即可使这些退化的性能得到完全恢复.催化性室温气体敏感金属氧化物陶瓷未来的主要研究方向包括进一步提高已知体系的室温气体敏感性能、探索对更多种类气体具有室温敏感性能的催化剂-金属氧化物半导体材料体系,以及优化周期性热处理制度,既使其对金属氧化物陶瓷基室温气体传感器工作的影响降到最低,又可降低室温气体敏感氧化物陶瓷传感器的成本并使其室温气敏性能长时间保持在较高的水平.

关键词：气体传感器金属氧化物室温陶瓷催化剂

Effects of Ba and Ti co-doping on BiFeO3 multiferroic ceramics optimized through two-step doping

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Journal of Advanced Ceramics 2016年第3期5卷 204-209页

作者： Sheng ZHU Yanhong GU Yao XIONG Xi ZHOU Yong LIU Yu WANG wanping chen Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education School of Physics and Technology Wuhan University Wuhan Hubei 430072 China School of Physics and Electronic Information Luoyang Normal College Luoyang Henan 471022 China School of Materials Science and Engineering Nanchang University Nanchang Jiangxi 330031 China

Ceramics of Bi0.9Ba0.1Fe0.925Ti x O3 (x = 0.0625, 0.08125, 0.0875, and 0.11) were prepared according to two doping strategies: one is called single-step doping in which Ba and Ti were doped together in calcination, while the other one is called two-step doping in which Ba and Ti were doped in calcination and sintering, respectively. Compared with samples prepared with single-step doping, those prepared with two-step doping have obviously different XRD patterns and small grains, and are dramatically improved in dielectric loss, resistivity, and remnant magnetization. A low dielectric loss of 0.05 at 103 Hz, a high resistivity of 4×1012 Ω·cm, and a large remnant magnetization of 1.5 emu/g, have been obtained simultaneously for Bi0.9Ba0.1Fe0.925Ti0.11O3 prepared with two-step doping. The contrast between these two doping strategies clearly reveals the importance of establishing a proper doping strategy when two or more elements are co-doped to BiFeO3.

关键词： BiFeO 3 doping multiferroic nonstoichiometric

Great Diversity in Stability of Perovskite-Type Oxides Studied by Electrochemical Hydrogen Charging

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Wuhan University Journal of Natural Sciences 2011年第3期16卷 255-259页

作者： PEI Yuchong chen wanping Key Laboratory of Artificial Micro- and Nanostructures of Ministry of Education School of Physics and Technology Wuhan University Wuhan 430072 Hubei China

Single crystals of 0.91Pb（Zn1/3Nb2/3）O3-0.09PbTiO3, SrTiO3 and BaTiO3, and ceramic pellets of CaCu3Ti4Oi2 and BiFeO3 have been studied and compared through electrochemical hydrogen charging, in which the oxides were coated with silver electrodes to electrolyze water as the cathode. Great diversity has been observed in the stability of the oxides： 0.91Pb（Zn1/3Nb2/3）O3- 0,09PbTiO3 was quickly decomposed; hydrogen could enter the lattice of the other four oxides, but their properties were influenced at extremely different speeds. Such a great diversity in stability against hydrogen among perovskite-type oxides highlights the importance of reliability study over functional oxides materials.

关键词： perovskite oxide stability hydrogen

Gas sensing capabilities of TiO_(2) porous nanoceramics prepared through premature sintering

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Journal of Advanced Ceramics 2015年第2期4卷 152-157页

作者： Yao XIONG Zilong TANG Yu WANG Yongming HU Haoshuang GU Yuanzhi LI Helen Lai Wah CHAN wanping chen Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education and School of Physics and Technology Wuhan UniversityWuhan 430072China School of Materials Science and Engineering State Key Laboratory of New Ceramics and Fine ProcessingTsinghua UniversityBeijing 100084China Department of Applied Physics and Materials Research Centre The Hong Kong Polytechnic UniversityHong KongChina Faculty of Physics and Electronic Technology Hubei UniversityWuhan 430062China State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China

Pure and noble metal(Pt,Pd,and Au)doped TiO_(2)nanoceramics have been prepared from TiO_(2)nanoparticles through traditional pressing and *** those samples sintered at 550℃,a typical premature sintering occurred,which led to the formation of a highly porous microstructure with a Brunauer-Emmett-Teller(BET)specific surface area of 23 m^(2)/*** room temperature,only Pt-doped samples showed obvious response to hydrogen,with sensitivities as high as~500 for 1000 ppm H_(2)in N_(2);at 300℃,all samples showed obvious responses to CO,while the responses of noble metal doped samples were much higher than that of the undoped *** mechanism for the observed sensing capabilities has been discussed,in which the catalytic effect of Pt for hydrogen is believed responsible for the room-temperature hydrogen sensing capabilities,and the absence of glass frit as commonly used in commercial thick-film metal oxide gas sensors is related to the high *** is proposed that much attention should be paid to metal oxide porous nanoceramics in developing gas sensors with high sensitivities and low working temperatures.

关键词： TiO_(2) porous nanoceramics premature sintering sensors hydrogen CO