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Investigation on the Formation Mechanism of Double-Layer Vertically Aligned Carbon Nanotube Arrays via Single-Step Chemical Vapour Deposition

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Nano-Micro Letters 2017年第1期9卷 137-143页

作者： Shoumo zhang Deli Peng Huanhuan Xie Quanshui Zheng yingying zhang Center for Nano and Micro Mechanics School of Aerospace EngineeringTsinghua UniversityBeijing 100084People’s Republic of China Department of Chemistry Tsinghua UniversityBeijing 100084People’s Republic of China State Key Laboratory of Tribology and Applied Mechanics Laboratory Tsinghua UniversityBeijing 100084People’s Republic of China

The mechanism for the formation of double-layer vertically aligned carbon nanotube arrays(VACNTs) through single-step CVD growth is investigated. The evolution of the structures and defect concentration of the VACNTs are tracked by scanning electron microscopy(SEM) and Raman spectroscopy. During the growth, the catalyst particles are stayed constantly on the substrate. The precipitation of the second CNT layer happens at around 30 min as proved by *** the growth of the first layer, catalyst nanoparticles are deactivated with the accumulation of amorphous carbon coatings on their surfaces, which leads to the termination of the growth of the first layer CNTs. Then, the catalyst particles are reactivated by the hydrogen in the gas flow, leading to the precipitation of the second CNT layer. The growth of the second CNT layer lifts the amorphous carbon coatings on catalyst particles and substrates. The release of mechanical energy by CNTs provides big enough energy to lift up amorphous carbon flakes on catalyst particles and substrates which finally stay at the interfaces of the two layers simulated by finite element analysis. This study sheds light on the termination mechanism of CNTs during CVD process.

关键词： Synthesis Vertically aligned carbon nanotube arrays CVD Double-layer

Fabrication of metal suspending nanostructures by nanoimprint lithography(NIL) and isotropic reactive ion etching(RIE)

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Science China(Technological Sciences) 2009年第5期52卷 1181-1186页

作者： XIE GuoYong zhang Jin zhang YongYi zhang yingying ZHU Tao LIU ZhongFan Center for Nanoscale Science and Technology(CNST) College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Nanotechnology Industrialization Base of China Tianjin 300457China

We report herein a rational approach for fabricating metal suspending nanostructures by nanoimprint lithography(NIL) and isotropic reactive ion etching(RIE).The approach comprises three principal steps:(1) mold fabrication,(2) structure replication by NIL,and(3) suspending nanostructures creation by isotropic *** this approach,suspending nanostructures with Au,Au/Ti or Ti/Au bilayers,and Au/Ti/Au sandwiched structures are *** Au nanostructures,straight suspending nanostructures can be obtained when the thickness of Au film is up to 50 nm for nano-bridge and 90 nm for nano-finger *** the thickness of Au is below 50 nm for nano-bridge and 90 nm for nano-finger,the Au suspending nanostructures bend upward as a result of the mismatch of thermal expansion between the thin Au films and Si *** leads to residual stresses in the thin Au *** Au/Ti or Ti/Au bilayers nanostructures,the cantilevers bend toward Au film,since Au has a larger thermal expansion coefficient than that of *** in the case of sandwich structures,straight suspending nanostructures are obtained,this may be due to the balance of residual stress between the thin films.

关键词： suspending nanostructure fabrication nanoimprint lithography(NIL) isotropic reactive ion etching(RIE)

The greater roles of indigenous microorganisms in removing nitrobenzene from sediment compared with the exogenous Phragmites australis and strain JS45

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Frontiers of Environmental Science & Engineering 2018年第1期12卷 125-135页

作者： Xiangqun Chi yingying zhang Daosheng Wang Feihua Wang Wei Liang State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China BGI-Qingdao Qingdao 266555 China

The feasibility of using Phragmites australis-JS45 system in removing nitrobenzene from sediments was conducted. However, it was observed that nitrobenzene degraded rapidly and was removed completely within 20 days in native sediments, raising the possibility that indigenous microorganisms may..p.y *** roles in nitroberzene degradation. Consequently, this. study aimed to verify thispossibility and invesUgate the potential mtrobenzene degraders among indigenous microorganisms in sediments. The abundance of inoculated strain JS45 and indigenous bacteria in sediments was quantified using real-time polymerase chain reaction. Furthermore, community structure of the indigenous bacteria was analyzed through high throughput sequencing based on lllumina MiSeq platform. The results showed that indigenous bacteria in native sediments were abundant, approximately 1014 CFU/g dry weight, which is about six orders of magnitude higher than that in

关键词： Community structureIndigenous microorganismsNitrobenzenePlant-microbe associated remediationSediment

CVD growth of fingerprint-like patterned 3D graphene film for an ultrasensitive pressure sensor

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Nano Research 2018年第2期11卷 1124-1134页

作者： Kailun Xia Chunya Wang Muqiang Jian Qi Wang yingying zhang Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education Department of Chemistry and Center for Nano and Micro Mechanics (CNMM) Tsinghua University Beijing China

With the rapid development of wearable devices, flexible pressure sensors with high sensitivity and wide workable range are highly desired. In nature, there are many well-adapted structures developed through natural selection, which inspired us for the design of biomimetic materials or devices. Particularl3 human fingertip skin, where many epidermal ridges amplify external stimulations, might be a good example to imitate for highly sensitive sensors. In this work, based on unique chemical vapor depositions （CVD）-grown three-dimensional （3D） graphene films that mimic the morphology of fingertip skin, we fabricated flexible pressure sensing membranes, which simultaneously showed a high sensitivity of 110 （kPa）-1 for 0-0.2 kPa and wide workable pressure range （up to 75 kPa）. Hierarchical structured polydimethylsiloxane （PDMS） films molded from natural leaves were used as the supporting elastic films for the graphene films, which also contribute to the superior performance of the pressure sensors. The pressure sensor showed a low detection limit （0.2 Pa）, fast response （〈 30 ms）, and excellent stability for more than 10,000 loading/unloading cycles. Based on these features, we demonstrated its applications in detecting tiny objects, sound, and human physiological signals, showing its potential in wearable electronics for health monitoring and human/machine interfaces.

关键词： electronic skin flexible pressure sensor three-dimensional (3D)graphene film fingertip skin hierarchical structures

Transcriptional responses to starvation of pathogenic Vibrio harveyi strain DY1

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Journal of Oceanology and Limnology 2020年第2期38卷 579-587页

作者： LIU Xiaodan GAO Xiaojian CHEN Nan zhang yingying LI Xixi zhang Yue zhang Xiaojun College of Animal Science and Technology Yangzhou University

Vibrio harveyi is a pathogen of various aquatic organisms that has been recently associated with massive mortality episodes in the aquaculture *** outbreaks of vibriosis are closely correlated with the capacity of this bacterial species to survive long-term starvation *** study the regulation mechanism of gene expression at the transcriptional level in *** under starvation conditions,the transcriptomic response profiles were determined of the Portunus trituberculatus pathogen *** strain DY1 under normal conditions and after four weeks of starvation.A total of 4679 and 4661 genes were expressed in the non-starved and starved cells,*** significantly differentially expressed genes(DEGs)between non-starved and starved groups were identified,in which 255 genes were up-regulated and 411 genes were *** analysis and KEGG enrichment analysis were used to analyze the DEGs and revealed the involvement of these DEGs in many pathways,including ABC transporters,flagellum assembly,and fatty acid *** DEGs were randomly selected and their expression levels were confirmed by quantitative real-time PCR(qRT-PCR).This is the first comprehensive transcriptomic analysis of starvation ef fects in *** findings will facilitate future study on stress adaptation and survival mechanisms of ***.

关键词： Vibrio harveyi starvation stress transcriptome sequencing differentially expressed genes adaptation and survival mechanisms

Fairy shrimp Branchinella kugenumaensis displays sensitivity to microplastic exposure

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Journal of Oceanology and Limnology 2024年第4期42卷 1186-1199页

作者： yingying zhang Xinrui XU Wenbo SUN Yuting WANG Hui YANG College of Animal Science and Technology Yangzhou UniversityYangzhou 225009China

The increasing global concern regarding plastic pollution has prompted the research into the consequences of microplastics(MPs)on aquatic *** shrimp Branchinella kugenumaensis are freshwater planktonic organisms that have existed for 250 million *** study aimed to uncover the harmful effects of MPs,with a particular focus on their size variations(0.1,1,and 5μm),on the fairy *** focused on how MPs could significantly affect the survival and growth of fairy ***,larger MPs,especially those measuring 5μm,caused higher mortality rates and hindered the growth compared to smaller *** impact of MPs continued even subsequent to depuration in clean *** accumulation of MPs within the intestines of fairy shrimp resulted in intestinal blockages,disrupted excretory functions,and harmed intestinal epithelial *** at the histological,cellular,and molecular levels showed that exposure to MPs triggered necroptosis in intestinal cells,accompanied by alterations in pathways related to transcription,translation,digestion,energy metabolism,and neurological ***,the effects of MPs on gene expression and pathways varied based on particle size,with larger MPs having a more significant effect and causing a strong response in xenobiotic biodegradation and metabolism *** suggest that the increasing severity of MPs pollution could pose a significant threat to the survival of fairy *** study provided vital insights into the complex relationship between microplastics and aquatic organisms,and highlighted the urgent need to address the potential devastating impact of plastic pollution on freshwater ***,due to their rapid growth,strong reproductive capacity,sensitivity,and ease of cultivation,fairy shrimp hold the potential candidate to serve as a model organism for studying the effects of MPs and other pollutants on freshwater ecosystems.

关键词： microplastic freshwater ecosystem toxic effects fairy shrimp model organism

Monodentate phosphorus-coordinated palladium(Ⅱ)complexes as new catalyst for Mizoroki-Heck reaction of aryl halides with electron-deficient olefins

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Chinese Chemical Letters 2018年第3期29卷 493-496页

作者： Fang Zhao Li Xin yingying zhang Xuefeng Jia School of Chemical and Material Science Shanxi Normal University Department of Chemistry Modern College of Arts and Sciences Shanxi Normal University

Four novel palladium（（Ⅱ）） complexes coordinated by phosphorus atoms from both 3,5-disubstituted-1H- 1,2,4-diazaphospholes in monodentate fashion were developed as efficient catalyst for the Mizoroki- Heck reaction of aryl halides with electron-deficient olefins. The coupling reaction of awl halide bearig different functional groups with olefin derivatives took place and the corresponding products were isolated in good to excellent yields under optimal conditions. The procedure exhibits good functional group tolerance and wide substrate scope. This Mizoroki-Heck reaction was further achieved using Pd（OAc）2 and 3,5-di-isopropyl-1H-1,2,4-diazaphospholes as combined catalyst, which provide the convenient and alternative method in organic synthesis

关键词： Palladium(Ⅱ) complexes Monodentate phosphine ligands Mizoroki-Heck reaction Aryl halides Olefins

Early Silurian Wuchuan–Sihui–Shaoguan exhalative sedimentary pyrite belt, South China: constraints from zircon dating for K-bentonite of the giant Dajiangping deposit

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Acta Geochimica 2021年第1期40卷 1-12页

作者： yingying zhang Taiyi Luo Tian Gan Mingzhong Zhou Xinqiao Han The State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 101407China International Center for Planetary Sciences College of GeosciencesChengdu University of TechnologyChengdu 610059China School of Geographical and Environmental Sciences Guizhou Normal UniversityGuiyang 550001China 'Guangdong Guangye Yunliu Pyrite Mining Co. LTDYunfu 527300China

The Wuchuan-Sihui-Shaoguan(WSS)exhalative sedimentary pyrite belt in the southwestern part of the Qinzhou-Hangzhou(Qin-Hang)belt is the most important sulfur industry base in ***,a wide range of metallogenetic ages spanning from Ediacaran to Devonian has been reported in the *** age range does not support the idea that the typical character of"coeval mineralization"in an exhalative sedimentary mineralization belt in China and ***,the precise determination of mineralization ages of representative deposits is necessary to provide guides for exploration and metallogenetic *** Dajiangping pyrite deposit is a typical example of this kind of deposits and is also the largest deposit with a proven reserve of 210 *** deposit was thought to have formed in Ediacaran or *** this study,2-3 layers of 10-25 cm thick 2M1-type microcrystalline muscovite slate abruptly embedded in the No.Ⅳmassive orebody of the deposit has been identified to be low-grade metamorphic K-bentonite.A Concordia zircon LA-ICP-MS U-Pb age of 432.5±1.3 Ma(mean standard weighted deviation of concordance and equivalence=1.2;N=11)has been yielded for the low-grade metamorphic *** age is distinctly different from the Rb-Sr isochron age of630.1±7.3 Ma for siliceous rock at the top of the No.Ⅲbanded orebody and the Re-Os isochron age of 389±62 Ma for pyrites from a laminated ***,it is close to the intercept age(429 Ma)of the youngest detrital zircons from sandstone interlayers of the No.Ⅲbanded *** Concordia age is also coincident with those of the Late Caledonian(400-460 Ma)magmatism-metamorphism events which are widely distributed in Cathaysia ***,it agrees well with that of the Early Silurian extensional volcanism(434-444 Ma)which have been revealed in the Dabaoshan,Siqian-Hekou,and Nanjing volcanic basins in northern Guangdong Province and southern Jiangxi ***,the dating result in this study conf

关键词： Wuchuan–Sihui–Shaoguan exhalative sedimentary pyrite belt Dajiangping pyrite deposit Lowgrade metamorphic K-bentonite Zircon U–Pb dating

Sweat-Driven Silk-yarn Switches Enabled by Highly Aligned Gaps for Air-conditioning Textiles

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Advanced Fiber Materials 2019年第3期1卷 197-204页

作者： Zhe Yin Songlin Shi Xiaoping Liang Mingchao zhang Quanshui Zheng yingying zhang Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China Center for Nano and Micro Mechanics Tsinghua UniversityBeijing 100084China Department of Engineering Mechanics School of Aerospace EngineeringTsinghua UniversityBeijing 100084China

Smart textiles are attracting great ***,air-conditioning textiles are highly desired for their merits in energy conservation and personal temperature/humidity ***,air-conditioning textiles can be fabricated by two *** uses infrared-radiation-adaptive materials,and the other uses moisture-responsive actuators that can regulate temperature and humidity ***,the fabrication of a silk-yarn switch comprising electrospun highly aligned nanofibers is reported and its application in air-conditioning textiles is *** yarn rotates in contact with liquid,and can be recovered by *** different responses and wetting behaviors of the switch to H_(2)O and C_(2)H_(6)O is *** is argued that alignment and surface hydrophilicity of nanofibers play important roles in this *** elaborate,actuating trait is mainly controlled by reduction of the surface free energy of aligned silk nanofibers,during the wetting *** proof of concept,the application of the sweat-driven silk-yarn switch in regulating the temperature/humidity of the human body is demonstrated in this *** the large production,versatile processibility,and good biocompatibility,silk actuator may have practical applications in designing smart switches(or valves)for intelligent textiles,artificial muscles,and other application scenarios.

关键词： Silk fibroin Aligned gaps Yarn actuator Surface free energy Dynamic regulation