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Pt3Ag alloy wavy nanowires as highly effective electrocatalysts for ethanol oxidation reaction

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Nano Research 2020年第5期13卷 1472-1478页

作者： Xiaoyang Fu Chengzhang Wan Aixin Zhang Zipeng Zhao Huaixun Huyan Xiaoqing Pan Shuaijing Du xiangfeng Duan Yu huang Department of Chemistry and Biochemistry University of CaliforniaLos AngelesLos AngelesCalifornia 90095USA Department of Materials Science and Engineering University of CaliforniaLos AngelesLos AngelesCalifornia 90095USA Department of Chemical Engineering and Materials Science University of CaliforniaIrvineIrvineCalifornia 92697USA Irvine Materials Research Institute(IMRI) University of CaliforniaIrvineIrvineCalifornia 92697USA Department of Physics and Astronomy University of CaliforniaIrvineIrvineCalifornia 92697USA California Nanosystems Institute University of CaliforniaLos AngelesLos AngelesCalifornia 90095USA

Direct ethanol fuel cell(DEFC)has received tremendous research interests because of the more convenient storage and transportation of ethanol *** ***,the electrocatalytic ethanol oxidation reaction typically requires precious metal catalysts and is plagued with relatively high over potential and low mass *** we report the synthesis of Pt3Ag alloy wavy nanowires via a particle attachment mechanism in a facile solvothermal *** microscopy studies and elemental analyses show highly wavy nanowire structures with an average diameter of 4.6±1.0 nm and uniform Pt3Ag alloy *** studies demonstrate that the resulting alloy nanowires can function as highly effective electrocatalysts for ethanol oxidation reactions(EOR)with ultrahigh specific activity of 28.0 mA/cm^2 and mass activity of 6.1 A/mg,far exceeding that of the commercial Pt/carbon samples(1.10 A/mg).The improved electrocatalytic activity may be partly attributed to partial electron transfer from Ag to Pt in the Pt3Ag alloy,which weakens CO binding and the CO poisoning *** one-dimensional nanowire morphology also contributes to favorable charge transport properties that are critical for extracting charge from catalytic active sites to external *** chronoamperometry studies demonstrate considerably improved stability for long term operation compared with the commercial Pt/C samples,making the Pt3Ag wavy nanowires an attractive electrocatalyst for EOR.

关键词： platinum silver alloy wavy nanowires electrocatalysis ethanol oxidation reaction(EOR)

In situ development of highly concave and compositionconfined PtNi octahedra with high oxygen reduction reaction activity and durability

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Nano Research 2016年第1期9卷 149-157页

作者： Enbo Zhu Yongjia Li Chin-Yi Chiu Xiaoqing huang Mufan Li Zipeng Zhao Yuan Liu xiangfeng Duan Yu huang Department of Materials Science and Engineering University of California Los Angeles CA 90095 USA Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA California NanoSystems Institute University of California Los Angeles CA 90095 USA

Controlled syntheses of PtNi metal nanocrystals with unique structures for catalyzing oxygen reduction reactions （ORRs） have attracted great interest. Here, we report the one-step synthesis of single-crystal PtNi octahedra with in situ-developed highly concave features and self-confined composition that are optimal for ORR. Detailed studies revealed that the Pt-rich seeding, subsequent Pt/Ni co-reduction, and Pt-Ni interfusion resulted in uniform single-crystal PtNi octahedra, and that the combination of Ni facet segregation and oxygen etching of a Ni-rich surface led to the concavity and confined Ni content. The concave PtNi nanocrystals exhibited much higher ORR performance than the commercially available Pt/C catalyst in terms of both specific activity （29.1 times higher） and mass activity （12.9 times higher） at 0.9 V （vs. reversible hydrogen electrode （RHE））. The performance was also higher than that of PtNi octahedra without concavity, confirming that the higher activity was closely related to its morphology. Moreover, the concave octahedra also exhibited remarkable stability in ORR （93% mass activity remained after 10,000 cycles between 0.6 and 1.1 V vs. RHE） owing to the passivation of the unstable sites.

关键词： PtNi alloy concave oxygen reduction reaction

Synthesis of surface controlled nickel/palladium hydride nanodendrites with high performance in benzyl alcohol oxidation

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Nano Research 2019年第6期12卷 1467-1472页

作者： Zipeng Zhao Michelle M.Flores Espinosa Jihan Zhou Wang Xue xiangfeng Duan Jianwei Miao Yu huang Department of Materials Science and Engineering University of CaliforniaLos AngelesCA 90095USA Department of Physics and Astronomy University of CaliforniaLos AngelesCA 90095USA Department of Chemistry and Biochemistry University of CaliforniaLos AngelesCA 90095USA California Nanosystems Institute University of CaliforniaLos AngelesCA 90095USA

Benzaldehyde byproduct is an imperative intermediate in the production of fine chemicals and *** selectivity to benzaldehyde is therefore critical in alcohol oxidation reactions at the industrial ***,we report a simple but innovative method for the synthesis of palladium hydride and nickel palladium hydride nanodendrites with controllable morphology,high stability,and excellent catalytic *** synthesized dendrites can maintain the palladium hydride phase even after their use in the chosen catalytic ***,the high surface area morphology and unique interaction between nickel-rich surface and palladium hydride (β-phase) of these nanodendrites are translated in an enhanced catalytic activity for benzyl alcohol oxidation *** Ni/PdH0.43 nanodendrites demonstrated a high selectivity towards benzaldehyde of about 92.0% with a conversion rate of 95.4%,showing higher catalytic selectivity than their PdH0.43 counterparts and commercial Pd/*** present study opens the door for further exploration of metal/metal-hydride nanostructures as next-generation catalytic materials.

关键词： benzyl alcohol selectivity benzaldehyde palladium hydride oxidation nanodendrites

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产妇产后综合护理干预的效果分析

临床医学工程 2018年第11期25卷 1543-1544页

作者：杨美燕刘秀芳黄祥凤钟燕珍郑丽玲陈年芳广东省龙川县妇幼保健院广东河源517300

目的探讨对产妇进行产后综合护理干预的临床效果。方法选择我院2016年1月至2017年12月收治的126例产妇,随机分为观察组和对照组各63例。对照组产后给予常规护理干预,观察组产后给予综合护理干预,比较两组产妇护理干预前后的SAS评分和SD... 详细信息

目的探讨对产妇进行产后综合护理干预的临床效果。方法选择我院2016年1月至2017年12月收治的126例产妇,随机分为观察组和对照组各63例。对照组产后给予常规护理干预,观察组产后给予综合护理干预,比较两组产妇护理干预前后的SAS评分和SDS评分,产后2 h、 24 h出血情况及护理满意度。结果护理干预前,两组产妇的SAS评分、 SDS评分比较差异均无统计学意义(P>0.05);护理干预后,观察组的SAS评分、 SDS评分均明显低于对照组(P <0.05)。观察组产后2 h、 24h出血量均显著少于对照组(P <0.05)。观察组的护理满意度为96.83%,显著高于对照组80.95%(P <0.05)。结论综合护理干预可明显改善产妇产后的不良情绪,减少其产后出血量,护理满意度较高,值得临床推广。

关键词：综合护理干预产后护理满意度

High risk factors for pulmonary fungous infection in intensive care units of neurosurgery

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Frontiers of Medicine 2007年第3期1卷 299-303页

作者： ZHU Wenyu TAN Liping CHEN xiangfeng huang Qiang LAN Qing Department of Neurosurgery Second Affiliated Hospital of Soochow UniversitySuzhou 215004China

By analyzing the high risk factors for pulmonary fungous infection in intensive care units of neurosurgery,the strategy of early diagnosis and treatment was *** to the domestic diagnostic standard on pulmonary fungous infection,clinical data on 58 patients with the infection in our department were *** hundred and seventeen strains of fungi were separated from the 58 *** was the most frequent type,accounting for 92.3%of the *** such as the severity of primary diseases,long-time coma,long-term use of broad-spectrum antibiotic,abuse of glucocorticoid,the open airway,and some invasive intubations,may be regarded as high risk factors for pulmonary fungous *** showed good clinical effects on the treatment of fungous *** eliminate these high risk factors,early diagnosis and the use of prophylactic antifungal agents can help reduce the incidence of pulmonary fungous infection.

关键词： intensive care units lung diseases,fungal infection neurosurgery

SIZ1-Mediated SUMOylation of ROS1 Enhances Its Stability and Positively Regulates Active DNA Demethylation in Arabidopsis

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Molecular Plant 2020年第12期13卷 1816-1824页

作者： xiangfeng Kong Yechun Hong Yi-Feng Hsu Huan huang Xue Liu Zhe Song Jian-Kang Zhu Shanghai Center for Plant Stress Biology and Center for Excellence in Molecular Plant Sciences Chinese Academy of SciencesShanghai 200032People's Republic of China University of Chinese Academy of Sciences BeijingPeople's Republic of China Department of Horticulture and Landscape Architecture Purdue UniversityWest LafayetteIN 47907USA

The 5-methylcytosine DNA glycosylase/lyase REPRESSOR OF SILENCING 1(ROS1)-mediated active DNA demethylation is critical for shaping the genomic DNA methylation landscape in *** and how the stability of ROS1 may be regulated by post-translational modifications is *** a methylation-sensitive PCR(CHOP-PCR)-based forward genetic screen forArabidopsis DNA hyper-methyl-ation mutants,we identified the SUMO E3 ligase SIZ1 as a critical regulator of active DNA *** of SIZ1 leads to hyper-methylation at approximately 1000 genomic ***1 physically in-teracts with ROS1 and mediates the SUMOylation of *** SUMOylation of ROS1 is reduced in siz1 mutant *** with that in wild-type plants,the protein level of ROS1 is significantly decreased,whereas there is an increased level of ROS1 transcripts in siz1 mutant *** results suggest that SIZ1-mediated SUMOylation of ROS1 promotes its stability and positively regulates active DNA demethylation.

关键词： SIZ1 SUMOylatoin ROS1 active DNA demethylation Arabidopsis

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间作苜蓿对毛白杨纸浆林生长和地力的影响

南京林业大学学报（自然科学版） 2013年第4期37卷 39-44页

作者：黄祥丰向地奎贾黎明高园园席本野王烨北京林业大学省部共建森林培育与保护教育部重点实验室北京100083 重庆市万州区林木种子站重庆404000

在宽窄行(2 m×1.5 m+8 m)栽植模式下,分析了间作紫花苜蓿(M1)对三倍体毛白杨纸浆林生长和地力的影响。结果表明:间作紫花苜蓿4 a后,纸浆林林木平均胸径、树高、单株材积与林分蓄积总生长量较间作棉花、小麦宽窄行栽植模式(M2)增长了6.... 详细信息

在宽窄行(2 m×1.5 m+8 m)栽植模式下,分析了间作紫花苜蓿(M1)对三倍体毛白杨纸浆林生长和地力的影响。结果表明:间作紫花苜蓿4 a后,纸浆林林木平均胸径、树高、单株材积与林分蓄积总生长量较间作棉花、小麦宽窄行栽植模式(M2)增长了6.04%、2.53%、13.33%与12.07%,较传统纸浆林栽植模式(M3)增长了28.18%、26.47%、70.00%与10.27%;M1、M2、M3处理下,0～60 cm各土层有机质、全氮、碱解氮含量与间作前相比都有不同程度的提高,而3种模式之间比较,M1、M2土壤有机质、全氮、碱解氮、速效钾含量高于M3;在比较经济效益后发现,M1模式4 a的总净收入最高,达到78 043.56元/hm2,较M2、M3分别提高了3.97%和38.73%。因此,可以在相似立地条件地区大规模推广间作紫花苜蓿的经营模式。

关键词：三倍体毛白杨纸浆林间作紫花苜蓿地力

新工科背景下工科专业课程中讨论课教学模式探索

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成都师范学院学报 2021年第7期37卷 45-51页

作者：王巧英黄翔峰王志伟徐竟成刘佳郑雄孙婧彭开铭同济大学环境科学与工程学院上海200092

新工科背景下,传统课堂教学模式已经难以满足社会对工科教育及工程技术人才培养的新要求。培养具有工程实践和创新能力的高素质复合型新工科人才,亟待推动工科教育改革和创新。讨论课作为改变单向知识灌输为主的讲授式教学模式,已经推... 详细信息

新工科背景下,传统课堂教学模式已经难以满足社会对工科教育及工程技术人才培养的新要求。培养具有工程实践和创新能力的高素质复合型新工科人才,亟待推动工科教育改革和创新。讨论课作为改变单向知识灌输为主的讲授式教学模式,已经推广应用于高校教学改革中。针对现行讨论课在开展过程中仍存在的诸多问题,按照新工科背景下人才培养需求,探讨了工科专业课程改革中讨论课的教学模式特征,阐述了讨论课的议题选择原则、教师角色定位、实施模式,以及评价体系建立、实施等关键环节的优化策略。以工业废水污染与防治课程教学为例,探索讨论课教学模式的实施过程,以期为国内工科专业讨论课教学模式的改革提供参考。

关键词：高校教学新工科讨论课成果导向教育

Chemical vapor deposition growth of monolayer MoSe2 nanosheets

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Nano Research 2014年第4期7卷 511-517页

作者： Jonathan C. Shaw Hailong Zhou Yu Chen Nathan O. Weiss Yuan Liu Yu huang xiangfeng Duan Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA Department of Materials Science and Engineering University of California Los Angeles CA 90095 USA California NanoSystems Institute University of California Los Angeles CA 90095 USA

The synthesis of two-dimensional （2D） layered materials with controllable thickness is of considerable interest for diverse applications. Here we report the first chemical vapor deposition growth of single- and few-layer MoSe2 nanosheets. By using Se and MoO3 as the chemical vapor supply, we demonstrate that highly crystalline MoSe2 can be directly grown on the 300 nm SiO2/Si substrates to form optically distinguishable single- and multi-layer nanosheets, typically in triangular shaped domains with edge lengths around 30 btm, which can merge into continuous thin films upon further growth. Micro-Raman spectroscopy and imaging was used to probe the thickness-dependent vibrational properties. Photoluminescence spectroscopy demonstrates that MoSe2 monolayers exhibit strong near band edge emission at 1.55 eV, while bilayers or multi-layers exhibit much weaker emission, indicating of the transition to a direct band gap semiconductor as the thickness is reduced to a monolayer.

关键词： chemical vapor deposition molybdenum diselenide two-dimensional materials transition metaldichalcogenide layered materials semiconductor