Online ISSN
1750-0443
Micro & Nano Letters
Volume 5, Issue 5, October 2010
Volumes & issues:
Volume 5, Issue 5
October 2010
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- Author(s): Y. Chan and J.M. Hill
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 247 –250
- DOI: 10.1049/mnl.2010.0058
- Type: Article
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In this Letter, the authors invéstigate the interaction of various atoms/ions with a graphene sheet and two parallel graphene sheets using the continuous approximation and the 6–12 Lennard-Jones potential. The authors assume that the carbon atoms are smeared across the surface of the graphene sheet so that the total interaction between the single atom/ion and the graphene sheet can be approximated by a surface integration over the graphene sheet. They determine the equilibrium position for the atom/ion on the surface of the graphene sheet and the minimum intermolecular spacing between two graphene sheets. This minimum spacing is by symmetry twice the value for the equilibrium positions for a single graphene sheet and is such that the atom/ion undergoes no net force. The same methodology together with basic statistical mechanics are also employed to investigate the diffusion of the atom/ion from a central location to the edge of the graphene sheet at different temperatures. The results presented in this Letter are consistent with a similar study adopting a molecular dynamics simulation approach. Possible applications of the present study might include the development of future drug delivery systems and future high-performance alkali battery design using nanomaterials as components. - Author(s): Y. Qiu ; L.Z. Hu ; D.Q. Yu ; H.Q. Zhang ; J.C. Sun ; B. Wang ; J.X. Ma ; L.N. Wang ; K.T. Sun ; Z.W. Zhao
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 251 –253
- DOI: 10.1049/mnl.2010.0086
- Type: Article
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A tail-like cluster composed of zinc oxide (ZnO) microwires had been synthesised by a simple chemical vapour deposition method at high temperature. Most of the microwires exhibit an interesting gear-shaped microstructure. A new model is proposed to interpret the growth mechanism of gear-shaped ZnO microwires. It is suggested that the gear-shaped ZnO microwires are formed by a coalescence of ZnO fine wires. A distinct ultraviolet emission band centred at 389.8 nm is observed in the photoluminescence spectrum. The gear-shaped microwires with high surface-to-volume ratio are expected to improve the physical, chemical and biological sensitivity of ZnO, which will be helpful for the further application of ZnO in the field of sensor devices. - Author(s): S.K. Tripathi ; N. Shukla ; N.S. Rajput ; A.K. Singh ; V.N. Kulkarni
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 254 –257
- DOI: 10.1049/mnl.2010.0071
- Type: Article
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The authors report a detailed study on the deposition because of scattered Ga ions during the focused ion beam chemical vapour deposition (FIB-CVD). The scattered ions strike the surface of the substrate nearby the base of the structure being fabricated by the primary ions, and decompose the organometallic molecules adsorbed on it, leading to the broadening of the base. Such deposition is dominant up to several micron distances from the base of the nanostructures depending on the primary ion flux. During the FIB-CVD, similar deposition occurs on the surface of nearby pre-fabricated structures, situated up to a few micrometre distances from the nanostructure being fabricated. The scattered-ion-induced deposition complicates the fabrication of complex 3D structures. The authors present the parametric dependence of the deposition because of scattered Ga ions during FIB-CVD. - Author(s): Zhuoqing Yang ; Guifu Ding ; Zhenwei Zhou ; Haogang Cai ; Xiaolin Zhao
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 258 –261
- DOI: 10.1049/mnl.2010.0067
- Type: Article
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Some regular raised strips are often introduced into microelectromechanical systems (MEMS) devices for avoiding the stiction between movable microstructures. An analytical model is proposed to evaluate the squeeze-film damping of MEMS suspension structure with anti-stiction raised strips by utilising reasonable boundary conditions. These raised strips cause a non-smooth pressure distribution between the moving and the fixed plates. The damping coefficients against distance between two plates with (and without) raised strips are also theoretically obtained by this analytical model. The two kinds of typical suspension microstructures have been fabricated by surface microelectroplating. Their vibration decay curves have been tested by laser detector. Calculated damping coefficients by amplitude envelopes are, respectively, about 0.34 and 0.05 N s/m when the moving plate reaches its initial position, which are in accordance with theoretical ones. - Author(s): S.R. Allahkaram ; M. Zoughi ; T. Rabizadeh
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 262 –265
- DOI: 10.1049/mnl.2010.0105
- Type: Article
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A possibility to increase materials' performance for different applications is to protect them by coatings. Electroless nickel deposition represents an alternative method to obtain coatings on various substrates. Advancement in electroless Ni–P deposition is the codeposition of solid particles within coatings. By this method, composite layers with very good characteristics for specific applications can be produced. Ni–9%P/nano-Al2O3 composite coatings were deposited by electroless plating method, while their morphology and properties were examined via scanning electron microscopy, energy dispersive X-ray spectroscopy and microhardness tests. Electrochemical impedance spectroscopy and polarisation method was used to analyse the corrosion resistance of the coatings. The results showed that the addition of nano-Al2O3 particles improved the corrosion resistance and mechanical properties of electroless Ni–P coatings. - Author(s): Ling-Yi Ding ; Wen-Pin Shih ; Yuh-Chung Hu ; Yi-Jie Chen ; Pei-Zen Chang
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 266 –269
- DOI: 10.1049/mnl.2010.0087
- Type: Article
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This study presents a post-CMOS electrochemical technique to improve the quality factor of standard CMOS inductors. This technique is a maskless process based on Silox Vapox III which possesses great etching selectivity between aluminium and SiO2 during electrochemical process. A porous silicon layer was generated on silicon substrate using this technique to increase the effective substrate resistance and to reduce the substrate loss. The result of the experiment showed that quality factor of a 1.5- and a 3.5-turn microinductor has been increased by 72.2 and 47%, respectively. A lumped-element model was used to analyse the effect of the presented technique. This technique provides a low-cost and effective process to modify CMOS components. - Author(s): Xunjun Yin ; Shougang Chen ; Aiguo Wu
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 270 –273
- DOI: 10.1049/mnl.2010.0117
- Type: Article
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A method of green chemistry synthesis of gold nanoparticles using lactic acid as a reducing agent is reported. The size and shape of gold nanoparticles are modulated by varying the ratio of metal salt and lactic acid in the reaction medium. The nanoparticles obtained are characterised by UV–vis, transmission electron microscopy (TEM) and X-ray diffraction (XRD). Crystalline nature of the nanoparticles in the face-centred cubic structure is confirmed by the peaks in the XRD pattern corresponding to (1 1 1), (2 0 0), (2 2 0) and (3 1 1) planes, which are bright circular spots in the selected area electron diffraction (SAED) and clear lattice fringes in the high-resolution TEM image. It is found that the size and shape of gold nanoparticles are strongly influenced by the molar ratio of HAuCl4 to lactic acid. Based on these results, a potential mechanism of this method of gold nanoparticle synthesis is also discussed. In future, more biological and medical applications of gold nanoparticles prepared by this method could be found based on their biocompatibility and solubility in aqueous solutions of lactic acid. - Author(s): S. Jacke ; J.L. Plaza ; J.P. Wilcoxon ; R.E. Palmer ; P. Beecher ; G. De Marzi ; G. Redmond ; A.J. Quinn ; Y. Chen
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 274 –277
- DOI: 10.1049/mnl.2010.0048
- Type: Article
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The authors report the fabrication and electrical characterisation of nanowires created via direct electron beam writing in films of passivated gold nanocrystals. Charge transport measurements yield room temperature resistances in the range 105–108 Ω. Variable temperature measurements yield two distinct sets of characteristics: activated conduction (high resistance) consistent with weakly coupled metal nanocrystals separated by alkyl–thiol tunnel barriers and quasi-localised behaviour (low resistance) consistent with stronger coupling between granular metallic islands in a carbonaceous matrix. The data indicate that electron beam writing is a promising method for local manipulation of inter-nanocrystal coupling in nanocrystal arrays. - Author(s): Guisheng Qi ; Youzhi Liu ; Weizhou Jiao ; Lixin Zhang
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 278 –281
- DOI: 10.1049/mnl.2010.0123
- Type: Article
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This Letter provides a template method to fabricate SiO2/β-Ni(OH)2 core/shell particles and hollow Ni(OH)2 microspheres through a hydrothermal process without any surface modifier. Hollow Ni(OH)2 microspheres with plicate surface are obtained after a SiO2 template is dissolved in the absence of NaOH. Experiments that differ in synthetic conditions are carried out to help in understanding the forming mechanism. The SiO2/β-Ni(OH)2 core/shell particles and hollow microspheres are characterised through X-ray diffraction (XRD), Fourier-transform infrared (FTIR), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The XRD and FTIR analyses indicate that the silica core is removed. SEM and TEM images confirm that Ni(OH)2 microspheres are hollow structured. - Author(s): M. van de Waterbeemd ; T. Sen ; S. Biagini ; I.J. Bruce
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 282 –285
- DOI: 10.1049/mnl.2010.0112
- Type: Article
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Work has been conducted to adapt a colourimetric assay previously used on flat surfaces for the assay of amine group density on nanoparticles silanised with 3-(aminopropyl) triethoxysilane. The new assay was rapid, easy to perform, and linear in the range of optical density (OD282 nm) values of 0.080–1.6 for particle suspension densities of between 0.5 and 7.0 mg/ml. In addition, the same materials, as well as the ones activated using 3-(aminopropyl) diethoxy methyl silane, were investigated for their elemental compositions by, combustion carbon-hydrogen-nitrogen (CHN) analysis and results from both approaches together have permitted the accurate calculation of the ratio of surface to total amine density for the materials when activated in water. This value can in turn be used as an indication of a surface amino structure (i.e. mono or multilayer). The aminosilanisation processes were further characterised by DNA-binding/elution and zeta potential measurement. This combination of approaches provides a fast, convenient and effective means of measuring surface amine densities on particles and yields information about the structure of the surface aminosilanes layers. - Author(s): S.H. Mahboobi ; A. Meghdari ; N. Jalili ; F. Amiri
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 286 –290
- DOI: 10.1049/mnl.2010.0039
- Type: Article
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One of the key factors in the assembly of nanoparticles and controlled construction of such systems is their positioning by a manipulation system. The response of clusters that are subjected to this process is of great importance. In this study, the behaviour of metallic nanoparticles during the manipulation process on an Au substrate is investigated using molecular dynamics. Two criteria are proposed for the evaluation of success in a pushing process regarding the intactness of a nanoparticle/substrate pair. The effects of cluster material, temperature and manipulation speed on the success of the process are investigated based on the simulation results. - Author(s): O.O. Adisa ; B.J. Cox ; J.M. Hill
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 291 –295
- DOI: 10.1049/mnl.2010.0075
- Type: Article
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In this study, the authors investigate methane storage, and in particular the binding and suction energies of methane in (8, 8) carbon and (10, 10) silicon nanotube bundles. Employing the Lennard–Jones potential together with the continuous approximation, they determine the interaction energy, molecular force and suction energy for a methane molecule in nanotube bundles. The authors approximate the methane molecule by assuming that the four hydrogen atoms are smeared over a spherical surface of a certain radius with the carbon atom located at the centre of the sphere. This is an important assumption in terms of simplifying the calculation, since with this model the particular orientations of the hydrogen atoms do not enter the calculation. Their results indicate that silicon nanostructures may be superior candidates for methane storage at high temperatures, particularly in the range 200–400 K. - Author(s): T. Bhuvana ; W. Boley ; B. Radha ; B.D. Dolash ; G. Chiu ; D. Bergstrom ; R. Reifenberger ; T.S. Fisher ; G.U. Kulkarni
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 296 –299
- DOI: 10.1049/mnl.2010.0109
- Type: Article
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Pd hexadecanethiolate and Pd butanethiolate precursors were patterned using inkjet printing techniques to form metallic Pd interconnects upon thermolysis. Patterns with lateral dimensions of ∼50 µm were produced. The surface morphology of the Pd interconnects was examined using scanning electron microscopy. By printing four-probe patterns, the resistance as a function of the precursor concentration was determined, allowing estimates for the resistivity of the printed interconnects. To demonstrate the utility of this fabrication approach, an electronic circuit consisting of single-wall carbon nanotubes was inkjet printed and then contacted with Pd pads. These printed patterns have also been applied as surface-enhanced Raman scattering substrates that exhibit high sensitivity. - Author(s): X. Wei ; N.H. Saad ; M.C.L. Ward
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 300 –303
- DOI: 10.1049/mnl.2010.0084
- Type: Article
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Manufacturing variation in the microfabrication process inevitably alters the size of the designed structure and thereafter influences the performance of the devices to some extent. A good knowledge of this effect will help the design and optimisation of the devices. In this study, the authors propose an analytical model to investigate the effect of manufacturing variation on the individual resonator in a chain of coupled micromechanical resonators. It is also used to estimate the variation caused by the manufacturing process based on the designed values and the measured eigenfrequencies. - Author(s): Lian-Yang Bai ; Yu-Ping Zhang ; Jun Chen ; Xiao-Mao Zhou ; Lin-Feng Hu
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 304 –308
- DOI: 10.1049/mnl.2010.0115
- Type: Article
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The purpose of this study was to develop a sensitive and low-cost optical sensor for screening pymetrozine using unmodified gold nanoparticles (G NPs). The presence of pymetrozine could rapidly induce the aggregation of G NPs, thereby resulting in red to deep blue colour change. The concentration of pymetrozine was determined with a limit of detection lower than 1×10−6 M by the naked eye and was further easily monitored by a UV–vis spectrometer. The highest selectivity was achieved in comparison with other 11 pesticides and the possible underlying mechanism was investigated in detail by the simultaneous addition of glutathione and pymetrozine in G NPs solution. - Author(s): Gilgueng Hwang and H. Hashimoto
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 309 –312
- DOI: 10.1049/mnl.2010.0066
- Type: Article
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The authors report gold nanoink-based in situ scanning electron microscope (SEM) compatible nanosoldering technique to interconnect three-dimensional thin-film nanostructures and electrodes for their assembly of nanoelectromechanical systems. Helical nanobelts are placed onto as-fabricated gold electrodes using nanomanipulation inside a SEM then deposited with gold nanoink to improve the electrical conductivity and mechanical stability. Electromechanical characterisations of helical nanobelts and nanowires reveal the reduced contact resistance and mechanically strong assembly. It is promising to the application of prototype device assembly and manipulations of various nanostructures. - Author(s): Youyi Sun ; Guizhen Guo ; Binghua Yang ; Xin Zhou ; Hongyue Cui ; Yaqing Liu ; Guizhe Zhao
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 313 –316
- DOI: 10.1049/mnl.2010.0108
- Type: Article
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A facile method to prepare polyaniline (PANI)/toluene-p-sulphonic acid (TSA) microrods guided by poly(vinyl pyrrolidone) (PVP) was developed. The structure of the PANI microrods was characterised by means of scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The average length and diameter of the microrods were about 25 and 7 µm, respectively. Furthermore, the effect of PVP concentration on morphology of the PANI was further investigated in detail. It showed that the morphology transferred from spheres to rods with increase in concentration. Moreover, the electrical and microwave absorption properties of products with various morphology (spheres and rods) were compared. And the result showed that the microrods products had higher electrical and microwave absorption properties compared with spherical products. - Author(s): Yu-Cheng Hsiao and Yao-Hsuan Tseng
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 317 –320
- DOI: 10.1049/mnl.2010.0094
- Type: Article
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The palladium-containing titanium dioxide films on glass substrate were prepared in a dip-coating process using a palladium-containing TiO2 sol. Following calcinations at 300°C, the authors rated the resulting film as having a hardness of 5 H as determined by a pencil scratch hardness tester. The photocatalytic activities were evaluated by decolourisation of methyl orange and degradation of NOx, respectively. Simple analysis was carried out using X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscope (SEM) and photoluminescence spectroscopy (PL) to observe changes in the film following palladium modification. Modification of TiO2 films with palladium enhanced the photocatalytic activity for decolourisation of dye and oxidation of NO. - Author(s): S. Yoshida ; T. Ono ; M. Esashi
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 321 –323
- DOI: 10.1049/mnl.2010.0128
- Type: Article
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This Letter reports on the deposition of a conductivity-switching polyimide film as a recording medium formed by molecular layer deposition (MLD). It also reports on the electrical modification on it using a scanning probe microscope (SPM). The polyimide film is uniformly deposited on an Au surface by MLD. As the result of the electrical modification, highly conductive dots pattern with a narrow pitch of approximately 50 nm is successfully defined by applying pulsed voltages. The current ratio of the electrical modified area to unmodified area reached 300 at least. - Author(s): M. Moradi ; A.H. Fereidon ; S. Sadeghzadeh
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 324 –327
- DOI: 10.1049/mnl.2010.0099
- Type: Article
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This Letter deals with modelling of nanorod manipulation using an atomic force microscope (AFM). Widespread application of nanorods and a lack of real-time imaging in nanotechnology make process modeling necessary. This model considers three basic nano forces: van der Waals, friction and adhesive contact force for a quantitative analysis of effective parameters. A dynamic analysis of nanorod pushing considering depression on an elastic substrate, indention between tip–nanorod and deflection along a straight path is presented. Incorporating a beam on the elastic substrate assumption, a complete model for nanorod manipulation is introduced. The model is verified using available (theoretical and experimental) results. A polystyrene nanorod is simulated and critical force and time, maximum deflection and safety factor are obtained. Aspect ratio and dimension effects are the most significant contributions of this work. Also, it is determined that the dynamic modes of micro- and nanorods are different. Despite rolling being a dominant mode in microrod manipulation, sliding is observed in nanorod pushing as the dominant dynamic mode. Results show that an increase in length causes considerable deflection and decrease in the safety factor. - Author(s): S. Kanthamani ; N. Srujana Vahini ; S. Raju ; V. Abhaikumar
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 328 –332
- DOI: 10.1049/mnl.2010.0073
- Type: Article
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Quasi-static numerical analysis of carbon nanotube (CNT) interconnects using meshless method is presented. Reproducing kernel particle method (RKPM) approach – a meshless technique is more efficient as compared with other regular discretisation approaches because of its adaptive nature. Numerical results for characteristic impedances (Zo) of CNT interconnects obtained using quasi-static capacitance are presented. Validation is done by comparing the obtained results with Luttinger liquid theory model and good agreement is obtained. The radio frequency performance of the CNT interconnects is completed using Agilent ADS with the quasi-static parameters obtained through RKPM. The simulation results in a return loss of −5.25 dB for a single CNT and −10.64 dB for CNT bundles accounting a power loss of 8.67% making it suitable for gigahertz applications. CNT bundles are the preferred candidates as interconnects to reduce the power loss in the circuit. - Author(s): F. Perdigones ; A. Luque ; J.M. Quero
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 333 –335
- DOI: 10.1049/mnl.2010.0106
- Type: Article
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A fabrication process to integrate polydimethylsiloxane (PDMS) in SU-8 structures is reported as an inexpensive alternative to reversible bonding. The integration lies in fabricating clamped PDMS membranes inside SU-8 structures. These PDMS-SU-8 structures include the advantages of both materials when necessary, that is, the flexibility of the PDMS in membranes and the rigidity of the SU-8 in rigid parts. The validity of the fabrication process is demonstrated by showing the behaviour of sample structures. The mechanical unions in these samples are tested for tightness and resistance to pressure, withstanding up to 1000 mbar. The process is especially suitable for microfluidic applications. - Author(s): Jianwei Zhao ; Lirong Qin ; Yong Zhang ; Yonghao Hao ; Qing Guo ; Lide Zhang
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 336 –339
- DOI: 10.1049/mnl.2010.0126
- Type: Article
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Cubic-phase ZnO nanowires with jagged surfaces were successfully synthesised through the Au-assisted chemical vapour deposition method. The nanowire has a fourfold symmetric shape with the diameter of tens of nanometres modulated along its axis. Especially, the interface between the catalyst droplet and the nanowire grows in epitaxial relationship. Thus, the authors believe that the property of Au particle may determine the crystalline structure and growth direction of the ZnO nanowires. The optical property of the products was also examined using photoluminescence spectroscopy. - Author(s): K.N. Shinde and S.J. Dhoble
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 340 –342
- DOI: 10.1049/mnl.2010.0129
- Type: Article
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One-step wet chemical synthesis of an Eu2+-activated Li2Sr2Al2PO4F9 nanophosphor is described. Formation of the compound was confirmed by X-ray diffraction and characterised by photoluminescence and transmission electron microscopy (TEM) technique. TEM observation showed an average diameter of about 50 nm for the particles with a spherical-like morphology. The prepared powders exhibited intense blue emission at the 430 nm owing to Eu2+ ion by Hg-free excitation at 355 nm, that is, solid-state lighting excitation. Hence, the availability of such a nanophosphor will significantly help in the development of blue-emitting solid-state lighting applications. - Author(s): Zhaoguang Pang ; Xinping Zhang ; Hongmei Liu
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 343 –346
- DOI: 10.1049/mnl.2010.0113
- Type: Article
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Solution-processible fabrication of plasmonic nanostructures onto the sidewall of fibres without length limitation is demonstrated, which can be directly used in simple liquid-level sensors based on fibre-coupled particle plasmon resonance. This sensor device actually consists of a bare fibre coated with randomly distributed gold nano-island structures on the sidewall, which is defined as the ‘plasmonic fibre’ in this context. In the fabrication process, colloidal gold nanoparticles are first coated on the sidewall of a bare fibre before being annealed at a temperature of 500°C. Particle plasmon resonance of the gold nano-island structures shows sensitive response to the change of the level of the liquid surrounding the fibre owing to the change in the environmental refractive index. The fibre does not only deliver the incident and signal light, but also mediates the interaction between the light and the gold nanostructures. This flexible sensor device based on the simple fabrication techniques enables a pure optical approach for the remote monitoring of the levels of special liquids with a sub-centimetre resolution, which may include flammable, toxic and non-transparent liquids that are not suitable to be detected using conventional techniques. - Author(s): Wen-Ming Zhang ; Guang Meng ; Zhi-Ke Peng
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 347 –350
- DOI: 10.1049/mnl.2010.0141
- Type: Article
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The surface of a microbearing in a microelectromechanical system (MEMS) or microfluidic device is described by a random roughness model characterised by fractal geometry. A modified Reynolds equation with velocity slip on the rough wall is used to describe the ultra-thin lubrication of the microbearing at a wide range of Knudsen number covering the slip and transition regimes. The effects of Knudsen number, bearing geometry parameters and roughness parameters on the flow behaviours, including pressure distribution, load carrying capacity, streamwise location of the load carrying capacity and shear stress, are all investigated and discussed. The results show that surface roughness influences not only pressure distribution and load carrying capacity but also shear stress distribution of the rarefied gas flow in microbearings. The flow over surfaces with higher relative roughness induces pressure fluctuation. It indicates that the effect of random surface roughness is of great significance in the analysis and design of gas-lubricated microbearings and should be comprehensively taken into account for MEMS and microfluidic devices. - Author(s): Lixin Zhang ; Tao Fan ; Hongfang Jiu ; Yixin Sun ; Xingwei Han ; Huan Cheng ; Zhenghao Li ; Guode Liu ; Qinglin Su
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 351 –354
- DOI: 10.1049/mnl.2010.0142
- Type: Article
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A facile approach for the fabrication of hollow carbon/anatase titania (C/TiO2) is demonstrated. The employed protocol involves the coating of silica template beads with layers of carbon. Furthermore, anatase titania is coated on SiO2/C through a sol–gel approach, followed by hydrothermal treatment at 180°C for 12 h, and hollow C/TiO2 is obtained by removal of silica using hydrofluoric acid (HF). The products are characterised by Fourier transform infrared, X-ray powder diffraction, transmission electron microscopy and scanning electron microscopy. The results show that the hollow carbon is supported on anatase titania with a diameter of 500 nm, and the wall thickness is about 70 nm. - Author(s): C. Riggio ; V. Raffa ; A. Cuschieri
- Source: Micro & Nano Letters, Volume 5, Issue 5, p. 355 –360
- DOI: 10.1049/mnl.2010.0089
- Type: Article
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Nanoparticles are increasingly being recognised for their potential utility in biomedicine. Here, the authors present a low-temperature, solvo-thermal method to synthesise zinc oxide (ZnO) nanorods using ZnO nanoparticles as precursors, with the addition of low-density polyethylenimine (PEI). This surfactant, which is in regular use in biology, has a double advantage: (i) it catalyses the synthesis owing to the amino groups on its polymeric chain and (ii) it wraps around ZnO nanorods as the crystal grows. The synthesis is followed by scanning electron microscopy, energy-dispersive spectroscopy and spectrophotometric analysis. The length of nanorods was dependent on the reaction time: around 300 nm, 1 µm and 5 µm, respectively, for 3, 6 and 12 h of reaction time. Toxicology studies showed that cellular response is both dose and size-dependent. Sub-1 µm ZnO nanorods were found to be internalised by cells and strongly affect cell viability with a process mediated by reactive oxygen species (ROS) production. The internalisation rate of bigger nanostructures is significantly lower, resulting in a moderate cytotoxicity with no detectable ROS production.
Modelling interaction of atoms and ions with graphene
Synthesis of gear-shaped ZnO microwires by chemical vapour deposition
Comprehensive analysis of the deposition caused by scattered Ga ions during focused ion-beam-induced deposition
Analytical model of squeeze film damping for microelectromechanical systems structures with anti-stiction raised strips
Studying the influence of nano-Al2O3 particles on morphology and corrosion improvement of Ni–9%P electroless coatings
CMOS compatible electrochemical process for improving quality factor of spiral microinductors
Green chemistry synthesis of gold nanoparticles using lactic acid as a reducing agent
Charge transport in nanocrystal wires created by direct electron beam writing
Template synthesis of β-Ni(OH)2 hollow microspheres through a hydrothermal process
Surface functionalisation of magnetic nanoparticles: quantification of surface to bulk amine density
Molecular dynamics study of ‘success evaluation’ for metallic nanoparticles manipulation on gold substrate
Encapsulation of methane in nanotube bundles
Inkjet printing of palladium alkanethiolates for facile fabrication of metal interconnects and surface-enhanced Raman scattering substrates
Analysis of manufacturing variation in a coupled microresonators array based on its designed values and measured eigenfrequencies
Rapid, sensitive and selective detection of pymetrozine using gold nanoparticles as colourimetric probes
Electromechanical property characterisation of three-dimensional helical nanobelts by in situ gold nanoink soldering
Synthesis of polyaniline microrods with high microwave absorption behaviours
Preparation of Pd-containing TiO2 film and its photocatalytic properties
Deposition of conductivity-switching polyimide film by molecular layer deposition and electrical modification using scanning probe microscope
Aspect ratio and dimension effects on nanorod manipulation by atomic force microscope
Quasi-static modelling of carbon nanotube interconnects for gigahertz applications
Integration of polydimethylsiloxane membranes in SU-8 structures
Catalytic growth of cubic phase ZnO nanowires with jagged surface
One-step synthesis of new blue-emitting Li2Sr2Al2PO4F9:Eu2+ nanophosphor
‘Plasmonic fibres’ and applications in liquid-level sensors
Random surface roughness effect on slider microbearing lubrication
Fabrication and characterisation of hollow carbon/anatase titania
Synthesis, characterisation and dispersion of zinc oxide nanorods for biomedical applications
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Most cited content for this Journal
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Vibration of piezoelectric nanofilm-based electromechanical sensors via higher-order non-local strain gradient theory
- Author(s): Mohammad Reza Farajpour ; Abbas Rastgoo ; Ali Farajpour ; Moslem Mohammadi
- Type: Article
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Approach for ambipolar behaviour suppression in tunnel FET by workfunction engineering
- Author(s): Kaushal Nigam ; Pravin kondekar ; Dheeraj Sharma
- Type: Article
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Spray coating of polymer electret with polystyrene nanoparticles for electrostatic energy harvesting
- Author(s): Yixin Xu ; Anxin Luo ; Ai Zhang ; Yulong Zhang ; Bin Tang ; Kai Wang ; Fei Wang
- Type: Article
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Two-dimensional functionalised methacrylated graphene oxide nanosheets as simple and inexpensive electrodes for biosensing applications
- Author(s): Seyed Morteza Naghib
- Type: Article
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UV-activated room temperature single-sheet ZnO gas sensor
- Author(s): Fanli Meng ; Hanxiong Zheng ; Yufeng Sun ; Minqiang Li ; Jinhuai Liu
- Type: Article
