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Linking, thinking & fixing:the story about the 2015 Chemistry Nobel Prize and the future of science

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Science Bulletin 2015年第23期60卷 2071-2076页

作者： Huan Meng Olivia J.Osborne Department of Medicine University of California Los Angeles centre for Environmental Implications of nanotechnology University of California Los Angeles

Did you know there are roughly over 10,000 DNA damages in a cell per day?Do not be too alarmed though,thanks to various vital DNA repair mechanisms we are able to continue function normally as an organism and maintain our genome integrity.It is no wonder then why this year prestigious Chemistry Nobel Prize(s)went to Drs.Thomas Lindahl,Aziz Sancar,and Paul Modrich for their

关键词：诺贝尔化学奖诺贝尔奖连接故事科学脱氧核糖核酸修复机制基因组

Advances in regenerative therapies for spinal cord injury:a biomaterials approach

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Neural Regeneration Research 2015年第5期10卷 726-742页

作者： Magdalini Tsintou Kyriakos Dalamagkas Alexander Marcus Seifalian UCL centre for nanotechnology & Regenerative Medicine Division of Surgery and Interventional ScienceUniversity College of London Royal Free London NHS Foundation Trust Hospital

Spinal cord injury results in the permanent loss of function, causing enormous personal, social and economic problems. Even though neural regeneration has been proven to be a natural mech- anism, central nervous system repair mechanisms are ineffective due to the imbalance of the inhibitory and excitatory factors implicated in neuroregeneration. Therefore, there is growing re- search interest on discovering a novel therapeutic strategy for effective spinal cord injury repair. To this direction, cell-based delivery strategies, biomolecule delivery strategies as well as scaf- fold-based therapeutic strategies have been developed with a tendency to seek for the answer to a combinatorial approach of all the above. Here we review the recent advances on regenerativel neural engineering therapies for spinal cord injury, aiming at providing an insight to the most promising repair strategies, in order to facilitate future research conduction.

关键词： tissue engineering neuroregeneration repair central nervous system biomaterial regenerative medicine nanotechnology spinal cord injury

Structural and mechanistic understanding of an active and durable graphene carbocatalyst for reduction of 4-nitrophenol at room temperature

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Nano Research 2015年第12期8卷 3992-4006页

作者： Huawen Hu John H. Xin Hong Hu Xiaowen Wang nanotechnology centre Institute of Textiles and Clothing The Hong Kong Polytechnic University Hong Kong SAR 999077 China

能代替基于金属的催化剂的活跃、持久、没有金属的 carbocatalyst 的发展具有增加科学、工艺的重要性。如此的催化剂的使用将避免例如，包含金属的催化剂引起的问题由稀罕金属资源的重金属和弄空的环境污染。此处，活跃、持久的 graphen... 详细信息

能代替基于金属的催化剂的活跃、持久、没有金属的 carbocatalyst 的发展具有增加科学、工艺的重要性。如此的催化剂的使用将避免例如，包含金属的催化剂引起的问题由稀罕金属资源的重金属和弄空的环境污染。此处，活跃、持久的 graphene carbocatalyst 在周围的温度为 4-nitrophenol 的 carbocatalytic 变换被介绍给 4-aminophenol。carbocatalyst 经由在 L 维生素酸(AA ) 和 graphene 氧化物之间的温和、以水为基的反应被准备(去) 并且没包含任何另外的反应物。在结构和催化性质优化期间，一系列 carbocatalysts 在各种各样的反应温度和 AA/GO 比率被制作。用几种描述技术，详细说明了这些 carbocatalysts 的结构的特征被识别。carbocatalysts 上的可能的活跃种类和地点也被识别例如某些包含氧的组，结合的系统，和 graphene 表边。另外，在这些之间的 synergistic 效果结果上的活跃种类和地点催化活动被加亮。而且，我们澄清了高稳定性的起源和优化 carbocatalyst 的耐久性。这里介绍的工作为加氢反应帮助高效的 carbocatalysts 的设计，并且在分子的水平增加结构、机械学的方面的理解导致高催化剂活动和耐久性。

关键词：结构特征氧化石墨活性物种对硝基苯酚耐用机理还原室温

The Effect of Variable Stator on Performance of a Highly Loaded Tandem Axial Flow Compressor Stage

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Journal of Thermal Science 2016年第3期25卷 223-230页

作者： Hamzeh Eshraghi Masoud Boroomand Abolghasem M.Tousi Mohammad Toude Fallah Ali Mohammadi Department of Aerospace Engineering and centre of excellence on computational aerospace engineering Amirkabir University of Technology nanotechnology Research and Application Center Sabanci University

Increasing the aerodynamic load on compressor blades helps to obtain a higher pressure ratio in lower rotational speeds.Considering the high aerodynamic load effects and structural concerns in the design process,it is possible to obtain higher pressure ratios compared to conventional compressors.However,it must be noted that imposing higher aerodynamic loads results in higher loss coefficients and deteriorates the overall performance.To avoid the loss increase,the boundary layer quality must be studied carefully over the blade suction surface.Employment of advanced shaped airfoils(like CDAs),slotted blades or other boundary layer control methods has helped the designers to use higher aerodynamic loads on compressor blades.Tandem cascade is a passive boundary layer control method,which is based on using the flow momentum to control the boundary layer on the suction surface and also to avoid the probable separation caused by higher aerodynamic loads.In fact,the front pressure side flow momentum helps to compensate the positive pressure gradient over the aft blade's suction side.Also,in comparison to the single blade stators,tandem variable stators have more degrees of freedom,and this issue increases the possibility of finding enhanced conditions in the compressor off-design performance.In the current study,a 3D design procedure for an axial flow tandem compressor stage has been applied to design a highly loaded stage.Following,this design is numerically investigated using a CFD code and the stage characteristic map is reported.Also,the effect of various stator stagger angles on the compressor performance and especially on the compressor surge margin has been discussed.To validate the CFD method,another known compressor stage is presented and its performance is numerically investigated and the results are compared with available experimental results.

关键词：级性能高负荷轴流压气机串联轴流式压缩机压气机叶片边界层控制空气动力载荷

Electromagnetic chirality-induced negative refraction with the same amplitude and anti-phase of the two chirality coefficients

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Chinese Physics B 2011年第6期20卷 447-452页

作者：赵顺才刘正东郑军黎根 School of Materials Science and Engineering Nanchang University Engineering Research centre for nanotechnology Nanchang University Institute of Modern Physics Nanchang University

This paper suggests a scheme of electromagnetic chirality-induced negative refraction utilizing magneto-lectric cross coupling in a four-level atomic system. The negative refraction can be achieved with the two chirality coefficients having the same amplitude but the opposite phase, without requiring the simultaneous presence of an electric-dipole and a magnetic-dipole transition near the same transition frequency.

关键词： electromagnetic chirality negative refraction same amplitude and anti-phase chirality coefficients

Cerium(Ⅳ)oxide nanocomposites:Catalytic properties and industrial application

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Journal of Rare Earths 2021年第2期39卷 129-139页

作者： Samira Bagheri Ibrahim Khalil Nurhidayatullaili Muhd Julkapli nanotechnology and Catalysis Research centre(NANOCAT) Institute for Advanced StudiesLevel 3Block AUniversity of Malaya50603 Kuala LumpurMalaysia

This review article provides a new insight on the application of cerium oxide(CeO_(2))-metal oxide nanocomposites as catalyst with enhanced reducibility and improved oxygen(O_(2))storage capacity,especially in the varying chemical reaction processes including combustion,oxidation,epoxidation and redox.The CeO_(2)-metal oxide interaction plays an important role in controlling particle size,O_(2) availability and coke resistance properties of the catalyst.Strong metal oxide-CeO_(2) interaction also assists in generating small and highly dispersed particles,resists sintering of catalyst particles during the catalysis process,and consequently improves the O_(2) availability of the catalyst.Indeed,CeO_(2) not only provides an active support to heterogeneous catalyst,but also creates a new active site at the metal-support interface to produce stronger nanoparticle bonding through the surface O_(2) vacancy.This consequently produces a heterogeneous catalytic system with promising reaction rate and catalytic stability in many industrial applications such as CO_(2) hydrogenation,CO oxidatio n,biodiesel productio n,gas reduction,photocatalytic and methane steam reforming.

关键词： Interface Composition Synergistic effect Active species Physiochemical Rare earths

Electrochemical Generation of Cubic Shaped Nano Zn_2SnO_4 Photocatalysts

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Nano-Micro Letters 2013年第2期5卷 101-110页

作者： Chandrappa K.Govindappa Venkatesha T.Venkatarangaiah Sharifah B.Abd Hamid nanotechnology & Catalysis (NANOCAT) research centre IPS Building University of Malaya Department of Chemistry Jnana Sahyadri Kuvempu University

In this contribution, an efficient and simple two-step hybrid electrochemical-thermal route was developed for the synthesis of cubic shaped Zn_2SnO_4 (ZTO) nanoparticles using aqueous sodium bicarbonate(NaHCO_3) and sodium stannate(Na_2SnO_3) electrolyte. The sacrificial Zn was used as anode and cathode in an undivided cell under galvanostatic mode at room temperature. The bath concentration and current density were respectively varied from 30 to 120 mmol and 0.05 to 1.5 A/dm^2. The electrochemically generated precursor was calcined for an hour at different range of temperature from 60 to 600. The crystallite sizes in the range of 24-53 nm were calculated based on Debye-Scherrer equation. Scanning electron microscope and transmission electron microscopy results reveal that all the particles have cubic morphology with diameter of40-50 nm. The as-prepared ZTO samples showed higher catalytic activity towards the degradation of methylene blue(MB) dye, and 90% degradation was found for the sample calcined at 600, which is greater than that of commercial TiO_2-P25 photocatalysts. The photodegradation efficiency of ZTO samples was found to be a function of exposure time and the dye solution p H value. These results indicate that the ZTO nanoparticles may be employed to remove dyes from wastewater.

关键词： Electrochemistry Zn2SnO4 Photocatalyst Cubic Nanoparticle

Effect of Media on the Electric Field of a Rhombic Nanostructure Array

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Chinese Physics Letters 2010年第6期27卷 217-220页

作者： ZHU Shao-Li ZHOU Wei Precision Engineering and nanotechnology centre School of Mechanical and Aerospace Engineering Nanyang Technological University 50 Nanyang Avenue Singapore 639798

Electric field distribution is an important parameter for nanostructure arrays in nanobiosensing appfications. It can influence the sensitivity and the resolution of nanobiosensors. We focus on the effect of media on the electric field distribution of a rhombic silver nanostructure array. The finite-difference time-domain algorithm- based numerical calculation method is used to monitor the electric field distribution of the silver nanostructures when the refractive index of the medium around the nanostructure array is changed. The calculated results show that tuning the refractive index of the medium around silver can have a considerable influence on the electric field distribution in the reflection and transmission directions. This effect can be used to increase the extinction efficiency and to improve the resolution of the spectra for nanobiosensing.

关键词： Electric field Fields Electricity Economic distribution Optical properties Uses Computers Silver

Recent progress of tungsten-and molybdenum-based semiconductor materials for solar-hydrogen production

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Tungsten 2019年第1期1卷 19-45页

作者： Songcan Wang Lianzhou Wang Nanomaterials centre School of Chemical Engineering and Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandBrisbaneQLD 4072Australia

Semiconductor-based solar water splitting is regarded as one of the most promising technologies for clean hydrogen produc-tion.The rational design of semiconductor materials is critically important to achieve high solar-to-hydrogen(STH)con-version efficiencies towards practical applications.A rich family of tungsten-and molybdenum-based materials have been developed as both photocatalysts and cocatalysts for solar-hydrogen production in the past years,providing more opportunities to achieve high solar-to-hydrogen(STH)efficiencies.In this review article,we comprehensively review the recent progress of tungsten-and molybdenum-based materials for solar-hydrogen production.In particular,the strengths and drawbacks of each material system are critically discussed,followed by an overview of the emerging strategies to improve their performances.Finally,the key challenges and possible research directions of tungsten-and molybdenum-based materials are presented,which would provide useful information for the design of efficient semiconductor materials for solar-hydrogen production.

关键词： Semiconductor Tungsten Molybdenum Photocatalyst Solar energy conversion Water splitting Hydrogen production