bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis, Properties and Potential Applications of Porous Graphene: A Review
Authors: Russo Paola , Hu Anming , Compagnini Giuseppe
Published: October 2014

Since the discovery of graphene, many efforts have been done to modify the graphene structure for integrating this novel material to nanoelectronics, fuel cells, energy storage devices and in many other applications. This leads to the production of different types of graphene-based materials, which possess properties different from those of pure graphene. Porous graphene is an example of this type of materials. It can be considered as a graphene sheet with some holes/pores within the atomic plane. Due to its spongy structure, porous graphene can have potential applications as membranes for molecular sieving, energy storage components and in nanoelectronics. In this review, we present the recent progress in the synthesis of porous graphene. The properties and the potential applications of this new material are also discussed.
Ligand Exchange of Colloidal ZnO Nanocrystals from the High Temperature and Nonaqueous Approach
Authors: Luo Jun , Dai Xingliang , Bai Sai , Jin Yizheng , Ye Zhizhen , Guo Xiaojun
Published: October 2014

Colloidal zinc oxide (ZnO) nanocrystals generated from the high temperature and nonaqueous approache are attractive for use in solution-processed electrical and optoelectronic devices. However, the as-prepared colloidal ZnO nanocrystals by this approach are generally capped by ligands with long alkyl-chains, which is disadvantage for solution-processed devices due to hindering charge transport. Here we demonstrate an effective ligand exchange process for the colloidal ZnO nanocrystals from the high temperature and nonaqueous approach by using n-butylamine. The ligand exchange process was carefully characterized. The thin films based on colloidal ZnO nanocrystals with ligand exchange exhibited dramatically enhanced UV photoconductivity.
Effects of Reaction Temperature on Microstructure and Advanced Pseudocapacitor Properties of NiO Prepared via Simple Precipitation Method
Authors: Sun Qiangqiang , Bao Shujuan
Published: October 2014

Morphology-controlled synthesis and large-scale self-assembly of nanoscale building blocks into complex nanoarchitectures is still a great challenge in nanoscience. In this work, various porous NiO nanostructures are obtained by a simple ammonia precipitation method and we find that the reaction temperature has a significant impact on their microstructures. Nanoflowers and nanoflakes have been obtained at 0°C and 50°C, while, weakly self-assembly nanoflowers with nanoflakes are formed at 20°C. In order to understand the process-structure-property relationship in nanomaterial synthesis and application, the as-prepared NiO is used as supercapacitor electrode materials, and evaluated by electrochemical measurement. The experimental results indicate that the material obtained at lower temperature has higher pseudocapacitance, the specific capacitance of 944, 889 and 410 F/g are reached for the materials prepared at 0°C, 20°C and 50°C and further calcined at 300°C, respectively. While the material obtained at higher temperature has excellent rate capacity. This offers us an opportunity searching for exciting new properties of NiO, and be useful for fabricating functional nanodevices.
Substitute of Expensive Pt with Improved Electrocatalytic Performance and Higher Resistance to CO Poisoning for Methanol Oxidation: the Case of Synergistic Pt-Co3O4 Nanocomposite
Authors: Zhao Hongxiao , Zheng Zhi , Li Jing , Jia Huimin , Wong Ka-wai , Zhang Yidong , Lau Woon Ming
Published: October 2014

In this paper, Pt-Co3O4 nanocomposite was synthesized by a sol-gel process combined with electrodeposition method. Its electrocatalytic activity towards methanol oxidation was investigated at room temperature using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and current density-time curve. It is found that the resultant Pt-Co3O4 catalysts with minute amount of Pt exhibite attractive electrocatalytic activity for methanol oxidation reaction (MOR) but with a high resistance CO poisoning due to the synergistic effects from Pt and Co3O4. Together with the low manufacturing cost of Co3O4, the reported nanostructured Pt-Co3O4 catalyst is expected to be a promising electrode material for direct methanol fuel cells (DMFC).
Development of Cd-doped Co Nanoparticles Encapsulated in Graphite Shell as Novel Electrode Material for the Capacitive Deionization Technology
Authors: Barakat Nasser A. M. , Khalil Khalil Abdelrazek , El-Deen Ahmad G. , kim Hak yong
Published: October 2014

Because of the low energy requirement and the environmentally safe byproducts, the capacitive deionization water desalination technology has attracted the attention of many researchers. The important requirements for electrode materials are good electrical conductivity, high surface area, good chemical stability and high specific capacitance. In this study, metallic nanoparticles that are encapsulated in a graphite shell (Cd-doped Co/C NPs) are introduced as the new electrode material for the capacitive deionization process because they have higher specific capacitance than the pristine carbonaceous materials. Cd-doped Co/C NPs perform better than graphene and the activated carbon. The introduced nanoparticles were synthesized using a simple sol-gel technique. A typical sol-gel composed of cadmium acetate, cobalt acetate and poly(vinyl alcohol) was prepared based on the polycondensation property of the acetates. The physiochemical characterizations that were used confirmed that the drying, grinding and calcination in an Ar atmosphere of the prepared gel produced the Cd-doped Co nanoparticles, which were encapsulated in a thin graphite layer. Overall, the present study suggests a new method to effectively use the encapsulated bimetallic nanostructures in the capacitive deionization technology.
Advances in Conceptual Electronic Nanodevices based on 0D and 1D Nanomaterials
Authors: Zhang Yafei , Duan Li Franklin , Zhang Yaozhong , Wang Jian , Geng Huijuan , Zhang Qing
Published: October 2014

Nanoelectronic devices are being extensively developed in these years with a large variety of potential applications. In this article, some recent developments in nanoelectronic devices, including their principles, structures and potential applications are reviewed. As nanodevices work in nanometer dimensions, they consume much less power and function much faster than conventional microelectronic devices. Nanoelectronic devices can operate in different principles so that they can be further grouped into field emission devices, molecular devices, quantum devices, etc. Nanodevices can function as sensors, diodes, transistors, photovoltaic and light emitting devices, etc. Recent advances in both theoretical simulation and fabrication technologies expedite the development process from device design to prototype demonstration. Practical applications with a great market value from nanoelectronic devices are expected in near future.
Polymer Nanoparticles Prepared by Supercritical Carbon Dioxide for in Vivo Anti-cancer Drug Delivery
Authors: Hua Maofang , Hua Xiufu
Published: October 2014

A new approach for producing polymer nanoparticles made of bovine serum albumin-poly(methyl methacrylate) conjugate by precipitating in supercritical CO2 is reported. The nanoparticles were loaded with the anti-tumor drug camptothecin. With albumin serving as a nutrient to cells, the drug-encapsulated nanoparticle shows an enhanced ability to kill cancer cells compared to that of the free drug in solution both in vitro and in vivo.
Efficiency Enhancement of Inverted Polymer Solar Cells Using Ionic Liquid-functionalized Carbon Nanoparticles-modified ZnO as Electron Selective Layer
Authors: Zhu Feng , Chen Xiaohong , Lu Zhe , Yang Jiaxiang , Huang Sumei , Sun Zhuo
Published: October 2014

ZnO thin film was fabricated on tin-doped indium oxide electrode as an electron selective layer of inverted polymer solar cells using magnetron sputtering deposition. Ionic liquid-functionalized carbon nanoparticles (ILCNs) film was further deposited onto ZnO surfaces by drop-casting ILCNs solution to improve interface properties. The power conversion efficiency (PCE) of inverted polymer solar cells (PSCs) with only ZnO layer was quickly decreased from 2.7% to 2.2% when the thickness of ZnO layer was increased from 15 nm to 60 nm. However, the average PCE of inverted PSCs with ZnO layer modified with ILCNs only decreased from 3.5% to 3.4%, which is comparable to that of traditional PSCs with poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) anode buffer layer. The results suggested that the contact barrier between ZnO layer and poly(3-hexylthiophene) and phenyl-C61-butyric acid methylester (P3HT:PCBM) blended film compared to ZnO bulk resistance can more significantly influence the performance of inverted PSCs with sputtered ZnO layer. The vanishment of negative capacitive behavior of inverted PSCs with ILCNs modified ZnO layer indicated ILCNs can greatly decrease the contact barrier of ZnO/P3HT:PCBM interface.
Effects of Magnetic Particles Entrance Arrangements on Mixing Efficiency of a Magnetic Bead Micromixer
Authors: Kamali Reza , Shekoohi Seyed Alireza , Binesh Alireza
Published: October 2014

In this study, a computer code is developed to numerically investigate a magnetic bead micromixer under different conditions. The micromixer consists of a microchannel and numerous micro magnetic particles which enter the micromixer by fluid flows and are actuated by an alternating magnetic field normal to the main flow. An important feature of micromixer which is not considered before by researchers is the particle entrance arrangement into the micromixer. This parameter could effectively affect the micromixer efficiency. There are two general micro magnetic particle entrance arrangements in magnetic bead micromixers: determined position entrance and random position entrance. In the case of determined position entrances, micro magnetic particles enter the micromixer at specific positions of entrance cross section. However, in a random position entrance, particles enter the microchannel with no order. In this study mixing efficiencies of identical magnetic bead micromixers which only differ in particle entrance arrangement are numerically investigated and compared. The results reported in this paper illustrate that the prepared computer code can be one of the most powerful and beneficial tools for the magnetic bead micromixer performance analysis. In addition, the results show that some features of the magnetic bead micromixer are strongly affected by the entrance arrangement of the particles.
Polyetheramide Templated Synthesis of Monodisperse Mn3O4 Nanoparticles with Controlled Size and Study of the Electrochemical Properties
Authors: He Lin , Zhang Geng , Dong Yuanzhu , Zhang Zhenwei , Xue Shihan , Jiang Xingmao
Published: October 2014

Monodisperse Mn3O4 nanoparticles were prepared solvothermally starting from manganese acetate by using polyether amide block copolymers (Pebax2533) as a template in isopropanol. The diameter of the nanoparticles in the range of 8.7 nm∼31.5 nm was decreased with increase of Pebax2533 concentration. The electrochemical properties and application in supercapacitor of Mn3O4 nanoparticles were further studied. The results showed that smaller nanoparticles had a larger capacitance. The higher capacitance of 217.5 F/g at a current density of 0.5 A/g was obtained on 8.7 nm Mn3O4 nanoparticles. The specific capacitance retention of 82% was maintained after 500 times of continuous charge-discharge cycles.
Electrospun MgO/Nylon 6 Hybrid Nanofibers for Protective Clothing
Authors: Dhineshbabu Nattanmai Raman , Karunakaran Gopalu , Suriyaprabha Rangaraj , Manivasakan Palanisamy , Rajendran Venkatachalam
Published: October 2014

Magnesia (MgO) nanoparticles were produced from magnesite ore (MgCO3) using ball mill. The crystalline size, morphology and specific SSA were characterized by X-ray diffraction analysis, transmission electron microscopy and Brunauer-Emmett-Teller method, respectively. MgO nanoparticle-incorporated nylon 6 solutions were electrospun to produce nanofiber mats. Surface morphology and internal structure of the prepared hybrid nanofiber mats were examined by scanning electron microscopy and high-resolution transmission electron microscopy, respectively. The fire retardancy and antibacterial activity (Staphylococcus aureus and Escherichia coli) of coated fabrics made from MgO/nylon 6 hybrid nanofiber are better than those from nylon 6 nanofiber.
RuRh Bimetallic Nanoparticles Stabilized by 15-membered Macrocycles-terminated Poly(propylene imine) Dendrimer: Preparation and Catalytic Hydrogenation of Nitrile—Butadiene Rubber
Authors: Wang Yang , Peng Xiaohong
Published: October 2014

A new fourth-generation poly(propylene imine) dendrimer (G4-M) containing 32 triolefinic 15-membered macrocycles on the surfaces has been synthesized. The bimetallic RuRh-dendrimer-stabilized nanoparticles (DSNs) were first prepared within G4-M by a co-complexation route. The new G4-M dendrimer has been characterized by 1H nuclear magnetic resonance, infrared radiation, and elemental analysis. The dendrimer-stabilized bimetallic ions and reduction courses were analyzed by UV-vis spectroscopy. High-resolution transmission electron microscopy and energy dispersive spectrometer were used to characterize the bimetallic nanoparticle size, size distribution, and particle morphology. The RuRh bimetallic DSNs showed high catalytic activity for the hydrogenation of nitrile-butadiene rubber.
Role of Contact and Contact Modification on Photo-response in a Charge Transfer Complex Single Nanowire Device
Authors: Basori Rabaya , Raychaudhuri A. K.
Published: October 2014

We investigated the feasibility of obtaining large photoresponse in metal-semiconductor-metal (MSM)type single nanowire device where one contact can be blocking type. We showed that suitable modification of the blocking contact by deposition of a capping metal using focused electron beam (FEB) can lead to considerable enhancement of the photoresponse. The work was done in a single Cu:TCNQ nanowire device fabricated by direct growth of nanowires (NW) from pre-patterned Cu electrode which makes the contact ohmic with the other contact made from Au. Analysis of the data shows that the large photoresponse of the devices arises predominantly due to reduction of the barriers at the Au/NW blocking contact on illumination. This is caused by the diffusion of the photo generated carriers from the nanowires to the contact region. When the barrier height is further reduced by treating the contact with FEB deposited Pt, this results in a large enhancement in the device photoresponse.
Position-resolved Surface Characterization and Nanofabrication Using an Optical Microscope Combined with a Nanopipette/Quartz Tuning Fork Atomic Force Microscope
Authors: An Sangmin , Sung Baekman , Noh Haneol , Stambaugh Corey , Kwon Soyoung , Lee Kunyoung , Kim Bongsu , Kim Qhwan , Jhe Wonho
Published: October 2014

In this work, we introduce position-resolved surface characterization and nanofabrication using an optical microscope (OM) combined with a nanopipette-based quartz tuning fork atomic force microscope (nanopipette/QTF-AFM) system. This system is used to accurately determine substrate position and nanoscale phenomena under ambient conditions. Solutions consisting of 5 nm Au nanoparticles, nanowires, and polydimethylsiloxane (PDMS) are deposited onto the substrate through the nano/microaperture of a pulled pipette. Nano/microscale patterning is performed using a nanopipette/QTF-AFM, while position is resolved by monitoring the substrate with a custom OM. With this tool, one can perform surface characterization (force spectroscopy/microscopy) using the quartz tuning fork (QTF) sensor. Nanofabrication is achieved by accurately positioning target materials on the surface, and on-demand delivery and patterning of various solutions for molecular architecture.
Highly Efficient Adsorption of Copper Ions by a PVP-Reduced Graphene Oxide Based On a New Adsorptions Mechanism
Authors: Zhang Yongji , Chi Huijuan , Zhang Wenhui , Sun Youyi , Liang Qing , Gu Yu , Jing Riya
Published: October 2014

Polyvinylpyrrolidone-reduced graphene oxide was prepared by modified hummers method and was used as adsorbent for removing Cu ions from wastewater. The effects of contact time and ions concentration on adsorption capacity were examined. The maximum adsorption capacity of 1689 mg/g was observed at an initial pH value of 3.5 after agitating for 10 min. It was demonstrated that polyvinylpyrrolidone-reduced graphene oxide had a huge adsorption capacity for Cu ions, which was 10 times higher than maximal value reported in previous works. The adsorption mechanism was also discussed by density functional theory. It demonstrates that Cu ions are attracted to surface of reduced graphene oxide by C atoms in reduced graphene oxide modified by polyvinylpyrrolidone through physisorption processes, which may be responsible for the higher adsorption capacity. Our results suggest that polyvinylpyrrolidone-reduced graphene oxide is an effective adsorbent for removing Cu ions in wastewater. It also provides a new way to improve the adsorption capacity of reduced graphene oxide for dealing with the heavy metal ion in wastewater.
Recent Progress on the Fabrication of Ultrafine Polyamide-6 Based Nanofibers Via Electrospinning: A Topical Review
Authors: Nirmala R. , Navamathavan R. , Park Soo-Jin , Kim Hak Yong
Published: October 2014

Electrospinning is a highly versatile technique to prepare continuous fibers with diameters of the order of nanometers. The remarkable high aspect ratio and high porosity bring electrospun nanofibers highly attractive to various nanotechnological applications such as filtration membranes, protective clothing, drug delivery, tissue-engineering, biosensors, catalysis, fuel cells and so on. In this review, we collectively summarized the recent progress in developments of the electrospun ultrafine polyamide-6 based nanofibers preparation, characterization and their applications. Information of this polyamide-6 and composites together with their processing conditions for electrospinning of ultrafine nanofibers has been summarized in this review. The recent developments made during last few years on these materials are addressed in this review. We are anticipating that this review certainly drive the researchers for developing more intensive investigation for exploring in many technological areas.
Singular Sheet Etching of Graphene with Oxygen Plasma
Authors: Al-Mumen Haider , Rao Fubo , Li Wen , Dong Lixin
Published: October 2014

This paper reports a simple and controllable post-synthesis method for engineering the number of graphene layers based on oxygen plasma etching. Singular sheet etching (SSE) of graphene was achieved with the optimum process duration of 38 seconds. As a demonstration of this SSE process, monolayer graphene films were produced from bilayer graphenes. Experimental investigations verified that the oxygen plasma etching removes a single layer graphene sheet in an anisotropic fashion rather than anisotropic mode. In addition, etching via the oxygen plasma at the ground electrodes introduced fewer defects to the bottom graphene layer compared with the conventional oxygen reactive ion etching using the powered electrodes. Such defects can further be reduced with an effective annealing treatment in an argon environment at 900–1000°C. These results demonstrate that our developed SSE method has enabled a microelectronics manufacturing compatible way for single sheet precision subtraction of graphene layers and a potential technique for producing large size graphenes with high yield from multilayer graphite materials.
A Bionic Fish Cilia Median-Low Frequency Three-Dimensional Piezoresistive MEMS Vector Hydrophone
Authors: Hang Guo-jun , Li Zhen , Wu Shu-juan , Xue Chen-yang , Yang Shi-e , Zhang Wen-dong
Published: October 2014

A bionic fish cilia median-low frequency three-dimensional MEMS vector hydrophone is reported in this paper. The piezoresistive reasonable position was obtained through finite element analysis by ANSYS and the structure was formed by MEMS processes including lithography, ion implantation, PECVD and etching, etc. The standing wave barrel results show that the lowest sensitivity of the hydrophone is −200 dB and reach up to −160 dB (in which the voltage amplification factor is 300). It has a good frequency response characteristics in 25 Hz ∼ 1500 Hz band. Directivity tests displayed that the hydrophone has a good “8”-shaped directivity, in which the resolution is not less than 30 dB, and asymmetry of the maximum axial sensitivity value is less than 1.2 dB.
Electrochemical Aptasensor Based on Prussian Blue-Chitosan-Glutaraldehyde for the Sensitive Determination of Tetracycline
Authors: Shen Guanghui , Guo Yemin , Sun Xia , Wang Xiangyou
Published: October 2014

In this paper, a novel and sensitive electrochemical aptasensor for detecting tetracycline (TET) with prussian blue (PB) as the label-free signal was fabricated. A PB-chitosan-glutaraldehyde (PB-CS-GA) system acting as the signal indicator was developed to improve the sensitivity of the electrochemical aptasensor. Firstly, the PB-CS-GA was fixed onto the glass carbon electrode surface. Then, colloidal gold nanoparticles (AuNPs) were droped onto the electrode to immobilize the anti-TET aptamer for preparation of the aptasensor. The stepwise assembly process of the aptasensor was characterized by cyclic voltammetry (C-V) and scanning electron microscope (SEM). The target TET captured onto the electrode induced the current response of the electrode due to the non-conducting biomoleculars. Under the optimum operating conditions, the response of differential pulse voltammetry (DPV) was used for detecting the concentration of TET. The proposed aptasensor showed a high sensitivity and a wide linear range of 10−9 ∼ 10−5 M and 10−5 ∼ 10−2 M with the correlation coefficients of 0.994 and 0.992, respectively. The detection limit was 3.2×10−10 M (RSD 4.12%). Due to its rapidity, sensitivity and low cost, the proposed aptasensor could be used as a pre-scanning method in TET determination for the analysis of livestock products.
Temperature-dependent of Nonlinear Optical Conductance of Graphene-based Systems in High-intensity Terahertz Field
Authors: Lv Jing , Yuan Rui-yang , Yan Hui
Published: October 2014

For multi-photon processed with the linear dispersion in the high-intensity terahertz (THz) field, we have systematically investigated the temperature-dependent nonlinear optical response of graphene-based systems, including single layer graphene, graphene superlattice and gapped graphene. In the intrinsic single layer graphene system, it demonstrates that, at low temperature, nonlinear optical conductivities of the thirdand fifth-order are respectively five and ten orders of magnitude larger than the universal conductivity with high-intensity and low frequency THz wave.In the graphene superlattice and gapped graphene systems, the optical responses enhanced because of the anisotropic massless and massive Dirac fermions.
A Cationic [60] Fullerene Derivative Reduces Invasion and Migration of HT-29 CRC Cells in Vitro at Dose Free of Significant Effects on Cell Survival
Authors: Lucafò Marianna , Pelillo Chiara , Carini Marco , Da Ros Tatiana , Prato Maurizio , Sava Gianni
Published: October 2014

Nanomaterials with unique characteristics exhibit favorable therapeutic and diagnostic properties, implying their enormous potential as biomedical candidates. C60 has been used in gene- and drug-delivery, as imaging agents, and as photosensitizers in cancer therapy. In this study, the influences of a cationic functionalized fullerene on cellular behavior of human colorectal cancer cell line (HT-29) were investigated. Results indicated that HT-29 treated with the studied compound showed a lower sensitivity but a significant impairment in migration and invasion by interfering with the activities of matrix metalloproteinases (MMP-2 and 9). The presence of fullerene also altered the capacity of adhesion-related proteins to perform their activity, thereby inducing dramatically adverse effects on the cell physiological functions such as cell adhesion. Thus, our study suggests that this compound is a new potential anti-metastatic effector and a therapeutic component for malignant colorectal cancer.
A Novel Photothermal Nanocrystals of Cu7S4 Hollow Structure for Efficient Ablation of Cancer Cells
Authors: Song Guosheng , Han Linbo , Zou Weiwei , Xiao Zhiyin , Huang XiaoJuan , Qin Zongyi , Zou Rujia , Hu Junqing
Published: October 2014

Cu2-xS nanocrystals (NCs), characterized by low cost, low toxicity, high stability and high photothermal conversion efficiency, provide promising platforms as photothermal agents. Herein, a novel two-step synthesis has been developed for Cu7S4 nanocrystals with hollow structure using the as-prepared copper nanoparticles as starting a solid precursor followed by hot-injection of sulfide source.The Cu7S4 NCs exhibit intense absorption band at Near-infrared (NIR) wavelengths due to localized surface plasmon resonance (LSPR) mode, which can effectively convert 980 nm-laser energy into heat.Moreover, the localized high temperature created by Cu7S4 NCs under NIR irradiation could result in efficient photothermal ablation (PTA) of cancer cells in vivo, demonstrating a novel and promising photothermal nanomaterials.
Fabrication, Characterization and Thermophysical Property Evaluation of SiC Nanofluids for Heat Transfer Applications
Authors: Nikkam Nader , Saleemi Mohsin , Haghighi Ehsan B. , Ghanbarpour Morteza , Khodabandeh Rahmatollah , Muhammed Mamoun , Palm Björn , Toprak Muhammet S.
Published: October 2014

Nanofluids (NFs) are nanotechnology-based colloidal suspensions fabricated by suspending nanoparticles (NPs) in a base liquid. These fluids have shown potential to improve the heat transfer properties of conventional heat transfer fluids. In this study we report in detail on fabrication, characterization and thermo-physical property evaluation of SiC NFs, prepared using SiC NPs with different crystal structures, for heat transfer applications. For this purpose, a series of SiC NFs containing SiC NPs with different crystal structure (α-SiC and β-SiC) were fabricated in a water (W)/ethylene glycol (EG) mixture (50/50 wt% ratio). Physicochemical properties of NPs/NFs were characterized by using various techniques, such as powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fouriertransform infrared spectroscopy (FTIR), dynamic light scattering (DLS) and Zeta potential analysis. Thermo-physical properties including thermal conductivity (TC) and viscosity for NFs containing SiC particles (α- and β- phase) weremeasured. The results show among all suspensions NFs fabricated with α-SiC particles have more favorable thermo-physical properties compared to the NFs fabricated with β-SiC.The observed difference is attributed to combination of several factors, including crystal structure (β- vs. α-), sample purity, and residual chemicals exhibited on SiCNFs. A TC enhancement of ∼20% while 14% increased viscosity were obtained for NFs containing 9 wt% of particular type of α-SiC NPs indicating promising capability of this kind of NFs for further heat transfer characteristics investigation.
Hydrogel Microneedle Arrays for Transdermal Drug Delivery
Authors: Hong Xiaoyun , Wu Zaozhan , Chen Lizhu , Wu Fei , Wei Liangming , Yuan Weien
Published: October 2014

Stratum corneum is the main obstacle for drugs to pass through the skin. Microneedles are composed of arrays of micro-projections formed with different materials, generally ranging from 25–2000 μm in height. Microneedles straightly pierce the skin with its short needle arrays to overcome this barrier. Microneedles can be divided into several categories, for instance, solid microneedles, coated microneedles, and hollow microneedles and so on. However, all these types have their weak points related to corresponding mechanisms. In recent years, pioneering scientists have been working on these issues and some possible solutions have been investigated. This article will focus on the microneedle arrays consisting of hydrogels. Hydrogels are commonly used in drug delivery field. Hydrogel microneedles can be further divided into dissolving and degradable microneedles and phase transition microneedles. The former leaves drug with matrix in the skin. The latter has the feature that drugs in the matrix are delivered while the remaining ingredients can be easily removed from the skin after usage. For drugs which are required to be used every day, the phase transition microneedles are more acceptable. This article is written in order to summarize the advantages of these designs and summarize issues to be solved which may hinder the development of this technology.
Pt-Containing Ag2S-Noble Metal Nanocomposites as Highly Active Electrocatalysts for the Oxidation of Formic Acid
Authors: Liu Hui , Feng Yan , Cao Hongbin , Yang Jun
Published: October 2014

Nanocomposites with synergistic effect are of great interest for their enhanced properties in a given application. Herein, we reported the high catalytic activity of Pt-containing Ag2S-noble metal nanocomposites in formic acid oxidation, which is a key reaction in direct formic acid fuel cell. The electrochemical measurements including voltammograms and chronoamperograms are used to characterize the catalytic property of Pt-containing nanocomposites for the oxidation of formic acid. In view of the limited literatures on using nanocomposites consisting of semiconductor and noble metals for catalyzing the reactions of polymer electrolyte membrane-based fuel cells, this study provides a helpful exploration for expanding the application of semiconductor-noble metal nanocomposites.
Torsional Characteristics of SingleWalled Carbon Nanotube with Water Interactions by Using Molecular Dynamics Simulation
Authors: Vijayaraghavan V. , Wong C. H.
Published: October 2014

The torsional characteristics of single walled carbon nanotube (SWCNT) with water interactions are studied in this work using molecular dynamics simulation method. The torsional properties of carbon nanotubes (CNTs) in a hydrodynamic environment such as water are critical for its key role in determining the lifetime and stability of CNT based nano-fluidic devices. The effect of chirality, defects and the density of water encapsulation is studied by subjecting the SWCNT to torsion. The findings show that the torsional strength of SWCNT decreases due to interaction of water molecules and presence of defects in the SWCNT. Additionally, for the case of water molecules encapsulated inside SWCNT, the torsional response depends on the density of packing of water molecules. Our findings and conclusions obtained from this paper is expected to further compliment the potential applications of CNTs as promising candidates for applications in nano-biological and nano-fluidic devices.
Unique Characteristics of Vertical Carbon Nanotube Field-effect Transistors on Silicon
Authors: Li Jingqi , Yue Weisheng , Guo Zaibing , Yang Yang , Wang Xianbin , Syed Ahad A. , Zhang Yafei
Published: October 2014

A vertical carbon nanotube field-effect transistor (CNTFET) based on silicon (Si) substrate has been proposed and simulated using a semi-classical theory. A single-walled carbon nanotube (SWNT) and an n-type Si nanowire in series construct the channel of the transistor. The CNTFET presents ambipolar characteristics at positive drain voltage (Vd) and n-type characteristics at negative Vd. The current is significantly influenced by the doping level of n-Si and the SWNT band gap. The n-branch current of the ambipolar characteristics increases with increasing doping level of the n-Si while the p-branch current decreases. The SWNT band gap has the same influence on the p-branch current at a positive Vd and n-type characteristics at negative Vd. The lower the SWNT band gap, the higher the current. However, it has no impact on the n-branch current in the ambipolar characteristics. Thick oxide is found to significantly degrade the current and the subthreshold slope of the CNTFETs.
White Organic Light Emitting Devices Based on Multiple Emissive Nanolayers
Authors: Madhava Rao M. V. , Kuin Su Yan , Huang T. S. , Chen Yi-Chun
Published: October 2014

In this paper, a white organic light-emitting device (WOLEDs) with multiple-emissive-layer structure has been fabricated. The device has a simple structure of indium tin oxide (ITO)/NPB (20 nm)//DPVBi(20 nm)/CDBP:xIr(btp)2acac(10 nm)/Alq3 (25 nm)/BCP (5 nm)/CsF (1 nm)/Al (150 nm) (x= 0.15, 2.5 and 3.0 wt%), where NPB and BCP are used as the hole-injecting layer, electron transporting and hole blocking layer, respectively. White light emission was realized in an OLED with 2.5% Ir(btp)2acac doping concentration. The device exhibits peak efficiency of 1.93 cd/A at 9 V and maximum brightness of 7005 cd/m2 at 14 V. The Commission International de I’Eclairage (CIE)(1931) coordinates of white emission are well within the white zone, which moves from (0.35,0.33) to (0.26,0.30) when the applied voltage is varied from 5 V to 14 V.
Enhanced Photoelectrochemical Properties of Cu2O-loaded Short TiO2 Nanotube Array Electrode Prepared by Sonoelectrochemical Deposition
Authors: Liu Yanbiao , Zhou Haibin , Li Jinhua , Chen Hongchong , Li Di , Zhou Baoxue , Cai Weimin
Published: October 2014

Copper and titanium remain relatively plentiful in earth crust. Therefore, using them in solar energy conversion technologies are of significant interest. In this work, cuprous oxide (Cu2O-modified short TiO2 nanotube array electrode was prepared based on the following two design ideas: first, the short titania nanotubes obtained from sonoelectrochemical anodization possess excellent charge separation and transportation properties as well as desirable mechanical stability; second, the sonoelectrochemical deposition technique favours the improvement in the combination between Cu2O and TiO2 nanotubes, and favours the dispersion of Cu2O particles. UV-Vis absorption and photo- electronchemical measurements proved that the Cu2O coating extended the visible spectrum absorption and the solar spectrum-induced photocurrent response. Under AM1.5 irradiation, the photocurrent density of the composite electrode (i.e. sonoelectrochemical deposition for 5 min) was more than 4.75 times as high as the pure nanotube electrode. Comparing the photoactivity of the Cu2O/TiO2 electrode obtained using sonoelectrochemical deposition with others that synthesized using plain electrochemical deposition, the photocurrent density of the former electrode was ∼2.2 times higher than that of the latter when biased at 1.0 V (vs. Ag/AgCl). The reproducible photocurrent response under intermittent illumination demonstrated the excellent stability of the composite electrode. Such kind of composite electrode material will have many potential applications in solar cell and other fields.
Poly(Glycidyl Methacrylates)-grafted Zinc Oxide Nanowire by Surface-initiated Atom Transfer Radical Polymerization
Authors: Zhang Bao , Hu Nantao , Wang Yanfang , Wang Zi , Wang Ying , Kong Eric S. , Zhang Yafei
Published: October 2014

Poly(glycidyl methacrylates) (PGMA) was grafted from zinc oxide (ZnO) nanowires via surface-initiated atom transfer radical polymerization (SI-ATRP) technique. Firstly, the ZnO nanowires were synthesized by the one-pot hydrothermal technique. Subsequently, the ZnO was functionalized with 3-aminopropyl triethoxysilane, which was converted to macroinitiator by the esterification of them with 2-bromopropionyl bromide. PGMA grafted ZnO nanowires (PGMA-ZnO) were then synthesized in an ATRP of the GMA with CuCl/2, 2`-bipyridine as the catalyst system. Kinetics studies revealed an approximate linear increase in weight of polymer with reaction time, indicating that the polymerization process owned some “living” character. The structure and composition of PGMA-ZnO were characterized with scanning electron microscope (SEM), energy-dispersive X-ray (EDX) spectrometer, fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA).
Fabrication of Y-junction Metal Nanowires by AAO Template-assisted AC Electrodeposition
Authors: Duan Huanan , Xia Zhenhai , Liang Jianyu
Published: October 2014

In this communication, we report a synthetic approach to fabricate Y-junction Co nanowires and Y-junction Cu nanowires by AC electrodeposition using a hierarchically designed anodized aluminum oxide template. Morphology study showe that diameters of the stems and branches of the Y-junction nanowires were about 40 nm and 20 nm respectively. Structural analysis indicates that Co nanowires had a mixture of face-center-cubic and hexagonal-close-packed structures, whereas Cu nanowires had a face-center-cubic structure with a <110> texture. The Y-junction Co nanowires exhibited a longitudinal coercivity of 1300 Oe and remnant magnetization of 56%, which was affected by the growth direction and microstructure. The present method can be extended to other metallic systems and thus provides a simple and efficient way to fabricate Y-junction metal nanowires.
Very-High Color Rendering Index Hybrid White Organic Light-Emitting Diodes with Double Emitting Nanolayers
Authors: Liu Baiquan , Xu Miao , Wang Lei , Tao Hong , Su Yueju , Gao Dongyu , Lan Linfeng , Zou Jianhua , Peng Junbiao
Published: October 2014

A very-high color rendering index white organic light-emitting diode (WOLED) based on a simple structure was successfully fabricated. The optimized device exhibits a maximum total efficiency of 13.1 and 5.4 lm/W at 1,000 cd/m2. A peak color rendering index of 90 and a relatively stable color during a wide range of luminance were obtained. In addition, it was demonstrated that the 4,4′,4″-tri(9-carbazoyl) triphenylamine host influenced strongly the performance of this WOLED. These results may be beneficial to the design of both material and device architecture for high-performance WOLED.
Cuprous Chloride Nanocubes Grown on Copper Foil for Pseudocapacitor Electrodes
Authors: Yin Bosi , Zhang Siwen , Zheng Xin , Qu Fengyu , Wu Xiang
Published: October 2014

In this paper, for the first time, we report the synthesis of nanoscale cuprous chloride (CuCl) cubic structure by a facile hydrothermal route. A possible mechanism for the growth of those nanostructures is proposed based on the experimental results. It is discovered that the existence of HCl could affect the surface of CuCl nanocubes. This unique cube-like nanostructure with rough surface significantly enhances the electroactive surface areas of CuCl, leading to a high special capacitance of 376 mF cm−2 at the current density of 1.0 mA cm−2. There is still a good reversibility with cycling efficiency of 88.8 % after 2,000 cycles, demonstrating its excellent long-term cycling stability and might be the promising candidates as the excellent electrode material.
Si-Based Anode Materials for Li-Ion Batteries: A Mini Review
Authors: Ma Delong , Cao Zhanyi , Hu Anming
Published: October 2014

Si has been considered as one of the most attractive anode materials for Li-ion batteries (LIBs) because of its high gravimetric and volumetric capacity. Importantly, it is also abundant, cheap, and environmentally benign. In this review, we summarized the recent progress in developments of Si anode materials. First, the electrochemical reaction and failure are outlined, and then, we summarized various methods for improving the battery performance, including those of nanostructuring, alloying, forming hierarchic structures, and using suitable binders. We hope that this review can be of benefit to more intensive investigation of Si-based anode materials.
Interorganizational Networks: Fundamental to the Accreditation Canada Program
Authors: Mitchell Jonathan I. , Nicklin Wendy , MacDonald Bernadette
Published: October 2014

Within the Canadian healthcare system, the term population-accountable health network defines the use of collective resources to optimize the health of a population through integrated interventions. The leadership of these networks has also been identified as a critical factor, highlighting the need for creative management of resources in determining effective, balanced sets of interventions. In this article, using specific principles embedded in the Accreditation Canada program, the benefits of a network approach are highlighted, including knowledge sharing, improving the consistency of practice through standards, and a broader systems-and-population view of healthcare delivery across the continuum of care. The implications for Canadian health leaders to leverage the benefits of interorganizational networks are discussed.
What Healthcare Leaders Can Learn from Research on Dark Networks
Authors: Milward H. Brinton
Published: October 2014

For 12 years, a research program has been conducted on “dark networks,” which are both illegal and covert. One of the major findings is that the structure of the network is conditioned by an existential dilemma—the need to act or exist. The more you do of one, the less you can do of the other. This article examines the findings of that research and applies it to the dilemmas of organizing healthcare networks.
Comparison of Automated Versus Traditional Nerve Conduction Study Methods for Median Nerve Testing in a General Worker Population
Authors: Dale Ann Marie , Agboola Folasade , Yun Amber , Zeringue Angelique , Al‐Lozi Muhammed T. , Evanoff Bradley
Published: October 2014

Objective

To investigate the validity of automated nerve conduction studies compared to traditional electrodiagnostic studies (EDS) for testing median nerve abnormalities in a working population.

Design

Agreement study and sensitivity investigation from 2 devices.

Setting

Field research testing laboratory.

Participants

Active workers from several industries participating in a longitudinal study of carpal tunnel syndrome.

Methods

Sixty‐two subjects received bilateral median and ulnar nerve conduction testing across the wrist with a traditional device and the NC‐stat automated device. We compared the intermethod agreement of analogous measurements.

Main outcome measurement

Nerve conduction study parameters.

Results

Median motor and sensory latency comparisons showed excellent agreement (intraclass correlation coefficients 0.85 and 0.80, respectively). Areas under the receiver operating characteristic curves were 0.97 and 0.96, respectively, using the optimal thresholds of 4.4‐millisecond median motor latency (sensitivity 100%, specificity 86%) and 3.9‐millisecond median sensory latency (sensitivity 100%, specificity 87%). Ulnar nerve testing results were less favorable.

Conclusion

The automated NC‐stat device showed excellent agreement with traditional EDS for detecting median nerve conduction abnormalities in a general population of workers, suggesting that this automated nerve conduction device can be used to ascertain research case definitions of carpal tunnel syndrome in population health studies. Further study is needed to determine optimal thresholds for defining median conduction abnormalities in populations that are not seeking clinical care.
Effects of Cardiopulmonary Resuscitation at High Altitudes on the Physical Condition of Untrained and Unacclimatized Rescuers
Authors: Narahara Hajime , Kimura Masafumi , Suto Takashi , Saito Hiroyuki , Tobe Masaru , Aso Chizu , Nishihara Fumio , Saito Shigeru
Published: October 2014

Objective

The authors experienced a case of prolonged cardiopulmonary resuscitation (CPR) on Mount Fuji (3776 m) that demanded strenuous work by the rescuers. The objective of this study was to provide information regarding the physiologic effects on the rescuers of performing CPR at moderate altitude.

Methods

The effects of CPR at 2700 m and 3700 m above sea level on the physical condition of the rescuers were studied in 8 male volunteers.

Results

Cardiopulmonary resuscitation for 5 minutes at 3700 m significantly reduced arterial blood oxygen saturation and increased rate-pressure products ( P < .05). Scores on the Borg scale, a subjective score of fatigue, after CPR action at 2700 m ( P < .05) and 3700 m ( P < .01) were higher than the scores at sea level.

Conclusions

Prolonged CPR at high altitude exerts a significant physical effect upon the condition of rescuers. A role for mechanical devices should be considered wherever possible.
The Epidemiology of Mountain Bike Park Injuries at the Whistler Bike Park, British Columbia (BC), Canada
Authors: Ashwell Zachary , McKay Mary Pat , Brubacher Jeffery R. , Gareau Annie
Published: October 2014

Objective

To describe the epidemiology of injuries sustained during the 2009 season at Whistler Mountain Bike Park.

Methods

A retrospective chart review was performed of injured bike park cyclists presenting to the Whistler Health Clinic between May 16 and October 12, 2009.

Results

Of 898 cases, 86% were male (median age, 26 years), 68.7% were Canadian, 19.4% required transport by the Whistler Bike Patrol, and 8.4% arrived by emergency medical services. Identification of 1759 specific injury diagnoses was made, including 420 fractures in 382 patients (42.5%). Upper extremity fractures predominated (75.4%), 11.2% had a traumatic brain injury, and 8.5% were transferred to a higher level of care: 7 by helicopter, 62 by ground, and 5 by personal vehicle. Two patients refused transfer.

Conclusions

Mountain bikers incurred many injuries with significant morbidity while riding in the Whistler Mountain Bike Park in 2009. Although exposure information is unavailable, these findings demonstrate serious risks associated with this sport and highlight the need for continued research into appropriate safety equipment and risk avoidance measures.
Comparing the Dynamics of Party Leadership Survival in Britain and Australia: Brown, Rudd and Gillard
Authors: Bennister Mark , Heppell Tim
Published: October 2014

This article examines the interaction between the respective party structures of the Australian Labor Party and the British Labour Party as a means of assessing the strategic options facing aspiring challengers for the party leadership. Noting the relative neglect within the scholarly literature of forced exits that occur and attempted forced exits that do not occur, this article takes as its case study the successful forced exits of Kevin Rudd and Julia Gillard, and the failure to remove Gordon Brown. In doing so the article challenges the prevailing assumption that the likely success of leadership evictions are solely determined by the leadership procedures that parties adopt. Noting the significance of circumstances and party cultures, the article advances two scenarios through which eviction attempts can be understood: first, forced exits triggered through the activation of formal procedures (Rudd and Gillard); second, attempts to force an exit by informal pressures beyond the formal procedures which are overcome by the incumbent (Brown).
SOME PROPERTIES OF SEMI-ABELIAN -GROUPS
Authors: BENMOUSSA MOHAMMED T. , GUERBOUSSA YASSINE
Published: October 2014

We prove a cohomological property for a class of finite $p$-groups introduced earlier by Xu, which we call semi-abelian $p$-groups. This result implies that a semi-abelian $p$-group has noninner automorphisms of order $p$, which settles a long-standing problem for this class. We answer also, independetly, an old question posed by Xu about the power structure of semi-abelian $p$-groups.