Journal of Nanomaterials The latest articles from Hindawi Publishing Corporation © 2015 , Hindawi Publishing Corporation . All rights reserved. Characterization and Bone Differentiation of Nanoporous Structure Fabricated on Ti6Al4V Alloy Mon, 30 Nov 2015 12:01:33 +0000 The optimal temperature for the alkaline treatment and subsequent heat treatment is determined to optimize the nanoporous structures formed on Ti6Al4V titanium alloy plates. Surface characterization of the alkali-heat treated samples was performed by scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. The effects of heating temperatures on albumin adhesion, rat bone marrow mesenchymal stem cells (BMMSCs) adhesion, alkaline phosphatase activity, osteocalcin production, calcium deposition, and Runx2 mRNA expression were evaluated. The nanotopography, surface chemistry, and surface roughness were unchanged even after heat treatments at 200, 400, and 600°C. Only the amorphous sodium titanate phase changed, increasing with the temperature of the heat treatments, which played a crucial role in promoting superior cell adhesion on the nanoporous surface compared with the sodium hydrogen titanate obtained by a single alkali treatment. The heat treatment at 800°C did not enhance cell attachment on the surface because the nanostructure was dramatically destroyed with the reappearance of Al and V. This study reveals that nanoporous structures with amorphous sodium titanate were fabricated on Ti6Al4V surface through an amended alkali-heat treatment process to improve BMMSCs adhesion. Yingmin Su, Satoshi Komasa, Tohru Sekino, Hiroshi Nishizaki, and Joji Okazaki Copyright © 2015 Yingmin Su et al. All rights reserved. CTAB-Assisted Hydrothermal Synthesis of WO3 Hierarchical Porous Structures and Investigation of Their Sensing Properties Mon, 30 Nov 2015 06:10:54 +0000 WO3 hierarchical porous structures were successfully synthesized via cetyltrimethylammonium bromide- (CTAB-) assisted hydrothermal method. The structure and morphology were investigated using scanning electron microscope, X-ray diffractometer, transmission electron microscopy, X-ray photoelectron spectra, Brunauer-Emmett-Teller nitrogen adsorption-desorption, and thermogravimetry and differential thermal analysis. The result demonstrated that WO3 hierarchical porous structures with an orthorhombic structure were constructed by a number of nanoparticles about 50–100 nm in diameters. The H2 gas sensing measurements showed that well-defined WO3 hierarchical porous structures with a large specific surface area exhibited the higher sensitivity compared with products without CTAB at all operating temperatures. Moreover, the reversible and fast response to H2 gas and good selectivity were obtained. The results indicated that the WO3 hierarchical porous structures are promising materials for gas sensors. Dan Meng, Guosheng Wang, Xiaoguang San, Yanbai Shen, Guodong Zhao, Yajing Zhang, and Fanli Meng Copyright © 2015 Dan Meng et al. All rights reserved. Size Effects of Pt Nanoparticle/Graphene Composite Materials on the Electrochemical Sensing of Hydrogen Peroxide Sun, 29 Nov 2015 13:06:19 +0000 The electrochemical detection of hydrogen peroxide (H2O2) has attracted much attention recently. Meanwhile, the size of nanoparticles which significantly influences electrocatalytic activity is crucial for electrocatalysts. Hence, we prepared five different size-selected Pt/graphene-modified glassy carbon (GC) electrodes to characterize H2O2 level via electrochemical measurements. During the preparation of the nanocomposites, size-selected Pt nanoparticles (NPs) with the mean diameter of 1.3, 1.7, 2.9, and 4.3 nm were assembled onto the graphene surfaces. The electrochemical measurement results are size-dependent for Pt NPs when sensing H2O2. When all cyclic voltammogram results from various electrodes are compared, the Pt-1.7 nm/G-modified GC electrode has the highest reduction current, the best detection limit, and the best sensitivity. Chia-Liang Sun, Jheng-Sin Su, Shun-Yi Lai, and Yu-Jen Lu Copyright © 2015 Chia-Liang Sun et al. All rights reserved. Bovine Serum Albumin and Chitosan Coated Silver Nanoparticles and Its Antimicrobial Activity against Oral and Nonoral Bacteria Sun, 29 Nov 2015 12:58:23 +0000 Antimicrobial agents have been developed for drug-resistance infections, which have been rapidly increasing; however, the control of involved microorganisms is still a challenge. In this work, SNP with bovine serum albumin (BSA) and chitosan (CS) coatings were prepared with an aqueous reduction method, characterized using dispersion light scattering, transmission electron microscopy, and thermal analysis. Antibacterial activity was tested on seven oral and nonoral bacteria by microdilution test and scanning electron microscopy. Six different sizes and shapes of coated SNP were prepared and used. Characterization revealed narrow size and good distribution of particles, spherical and pseudospherical shapes, and the presence of coatings on the SNP surfaces. All samples showed antimicrobial activity, although smaller sizes and CS samples had the best inhibition effects. The highest microbial resistance was shown by Gram-positive bacteria. Although coated SNP action depends on particular bacterium, BSA and CS coated SNP could be used for drug-resistance infections. León Francisco Espinosa-Cristóbal, Gabriel Alejandro Martínez-Castañón, Juan Pablo Loyola-Rodríguez, Nereyda Niño-Martínez, Facundo Ruiz, Norma Verónica Zavala-Alonso, René H. Lara, and Simón Yobanny Reyes-López Copyright © 2015 León Francisco Espinosa-Cristóbal et al. All rights reserved. The Role of Edge Dislocations on the Red Luminescence of ZnO Films Deposited by RF-Sputtering Sun, 29 Nov 2015 11:47:24 +0000 The existence of extended defects (i.e., dislocations) in inorganic semiconductors, such as GaN or ZnO, responsible for broad emission peaks in photoluminescence analysis remains unresolved. The possible assignments of these luminescence bands are still matter of discussion. In this study, two different zinc oxide samples, grown under different oxygen partial pressures and substrate temperatures, are presented. Epitaxial and structural properties were analysed by means of X-ray diffraction and transmission electron microscopy techniques. They confirm that the layers are single-phase with a good crystalline quality. Nevertheless, a different density of threading dislocations, with a higher contribution of edge dislocations, was found. Photoluminescence spectroscopy has been used to investigate the optical properties. The steady state luminescence spectra performed at 14 K evidenced the donor bound exciton recombination and deep green and red emission bands. The red band with a maximum at 1.78 eV was found to be stronger in the sample grown at lower oxygen pressure which also shows higher density of threading dislocations. From the temperature and excitation density dependence of the red band, a donor acceptor pair recombination model was proposed, where hydrogen and zinc vacancies are strong candidates for the donor and acceptor species, respectively. Rocío Félix, Marco Peres, Sergio Magalhães, Maria Rosario Correia, Armando Lourenço, Teresa Monteiro, Rafael García, and Francisco M. Morales Copyright © 2015 Rocío Félix et al. All rights reserved. Self-Lubricating Polytetrafluoroethylene/Polyimide Blends Reinforced with Zinc Oxide Nanoparticles Sun, 29 Nov 2015 11:33:46 +0000 ZnO nanoparticle reinforced polytetrafluoroethylene/polyimide (PTFE/PI) nanocomposites were prepared and their corresponding tribological and mechanical properties were studied in this work. The influences of ZnO loading, sliding load, and velocity on the tribological properties of ZnO/PTFE/PI nanocomposites were systematically investigated. Results reveal that nanocomposites reinforced with 3 wt% ZnO exhibit the optimal tribological and mechanical properties. Specifically, the wear loss decreased by 20% after incorporating 3 wt% ZnO compared to unfilled PTFE/PI. Meanwhile, the impact strength, tensile strength, and elongation-at-break of 3 wt% ZnO/PTFE/PI nanocomposite are enhanced by 85, 5, and 10% compared to pure PTFE/PI blend. Microstructure investigation reveals that ZnO nanoparticles facilitate the formation of continuous, uniform, and smooth transfer film and thus reduce the adhesive wear of PTFE/PI. Liwen Mu, Jiahua Zhu, Jingdeng Fan, Zhongxin Zhou, Yijun Shi, Xin Feng, Huaiyuan Wang, and Xiaohua Lu Copyright © 2015 Liwen Mu et al. All rights reserved. Development of Polymeric Nanoparticles of Garcinia mangostana Xanthones in Eudragit RL100/RS100 for Anti-Colon Cancer Drug Delivery Sun, 29 Nov 2015 06:03:20 +0000 Xanthones are a group of oxygenated heterocyclic compounds with anticancer properties, but poor aqueous solubility and low oral bioavailability hinder their therapeutic application. This study sought to prepare a xanthones extract (81%  α-mangostin and 16%  γ-mangostin) in polymeric nanoparticles and to investigate its intracellular delivery and cytotoxicity toward colon cancer cells. The nanoparticles were prepared in Eudragit RL100 and Eudragit RS100 by the nanoprecipitation method at drug loading and entrapment efficiency of 20% and >95%, respectively. Freeze-drying of bulk nanoparticle solutions, using glucose or sucrose as cryoprotectants, allowed the collection of nanoparticles at >95% yield. Solubility of the xanthones extract was improved from 0.1 µg/mL to 1250 µg/mL. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) of the freeze-dried final formulation showed the presence of cationic round nanoparticles, with particle size in the range of 32–130 nm. Scanning electron microscopy (SEM) showed the presence of nanospheres, and Fourier transform infrared (FTIR) spectroscopy indicated intermolecular interaction of xanthones with Eudragit polymers. Cellular uptake of nanoparticles was mediated via endocytosis and indicated intracellular delivery of xanthones associated with potent cytotoxicity (median inhibitory concentration  µg/mL). Presented results suggest that cationic nanoparticles of xanthones may provide a novel oral drug delivery system for chemoprevention or treatment of intestinal and colon tumors. Abdalrahim F. A. Aisha, Amin Malik Shah Abdulmajid, Zhari Ismail, Salman A. Alrokayan, and Khalid M. Abu-Salah Copyright © 2015 Abdalrahim F. A. Aisha et al. All rights reserved. Morphology Effect on Enhanced Li+-Ion Storage Performance for Ni2+/3+ and/or Co2+/3+ Doped LiMnPO4 Cathode Nanoparticles Thu, 26 Nov 2015 13:17:59 +0000 The electrochemical performance of Li(Mn, M)PO4 (M = Co2+/3+, Ni2+/3+) was investigated with regard to the particle morphology. Within a controlled chemical composition, Li(Mn0.92Co0.04Ni0.04)PO4, the resultant cathode exhibited somewhat spherical-shaped nanocrystalline particles and enhanced Li+-ion storage, which was even better than the undoped LiMnPO4, up to 16% in discharge capacity at 0.05 C. The outstanding electrochemical performance is attributed to the well-dispersed spherical-shaped particle morphology, which allows the fast Li+-ion migration during the electrochemical lithiation/delithiation process, especially at high current density. Young Jun Yun, Mihye Wu, Jin Kyu Kim, Ji Young Ju, Sun Sook Lee, Ki Woong Kim, Woon Ik Park, Ha-Kyun Jung, Kwang Ho Kim, Jin-Seong Park, and Sungho Choi Copyright © 2015 Young Jun Yun et al. All rights reserved. Synthesis of ZnO Nanowires and Their Photovoltaic Application: ZnO Nanowires/AgGaSe2 Thin Film Core-Shell Solar Cell Thu, 26 Nov 2015 11:48:38 +0000 In this investigation, hydrothermal technique was employed for the synthesis of well-aligned dense arrays of ZnO nanowires (NWs) on a wide range of substrates including silicon, soda-lime glass (SLG), indium tin oxide, and polyethylene terephthalate (PET). Results showed that ZnO NWs can be successfully grown on any substrate that can withstand the growth temperature (~90°C) and precursor solution chemicals. Results also revealed that there was a strong impact of growth time and ZnO seed layer deposition route on the orientation, density, diameter, and uniformity of the synthesized nanowires. A core-shell n-ZnO NWs/p-AgGaSe2 (AGS) thin film solar cell was fabricated as a device application of synthesized ZnO nanowires by decoration of nanowires with ~700 nm thick sputtering deposited AGS thin film layer, which demonstrated an energy conversion efficiency of 1.74% under 100 mW/cm2 of simulated solar illumination. Elif Peksu and Hakan Karaagac Copyright © 2015 Elif Peksu and Hakan Karaagac. All rights reserved. Enhancement of Visible Upconversion Emission in Y2O3:Er3+-Yb3+ by Addition of Thiourea and LiOH in the Phosphor Synthesis Thu, 26 Nov 2015 07:22:33 +0000 Spherical like Y2O3 nanostructures doped with Er3+ and Yb3+ ions have been synthesized by a facile hydrothermal method. The samples were prepared by using different precipitant agents in the synthesis process. The phosphors were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence spectroscopy. Effects of the precipitant agents on structural, morphological, and photoluminescence properties of Y2O3:Er3+-Yb3+ are studied and discussed. XRD analysis indicates that all samples, prepared with different precipitant agents, present the same cubic phase. Electron microscopy measurements show regular spherical shapes with size diameter depending on precipitant agent. Photoluminescence reveals that the samples have strong green (563 nm) and red (660 nm) emissions corresponding to 4S3/2 → 4I15/2 and 4F9/2 → 4I15/2 transitions of Er3+ ions, respectively. The nanophosphors prepared with both Thiourea and Lithium Hydroxide exhibit the stronger visible upconversion luminescence under 980 nm diode laser excitation. Eder Resendiz-L, Luis Armando Diaz-Torres, Luis Octavio Meza Espinoza, Claramaria Rodríguez-González, and Pedro Salas Copyright © 2015 Eder Resendiz-L et al. All rights reserved. Plasmon-Enhanced Sensing: Current Status and Prospects Wed, 25 Nov 2015 14:26:13 +0000 By combining different plasmonic nanostructures with conventional sensing configurations, chemical/biosensors with significantly enhanced device performance can be achieved. The fast development of plasmon-assisted devices benefits from the advance of nanofabrication technology. In this review, we first briefly show the experimental configurations for testing plasmon enhanced sensing signals and then summarize the classic nanogeometries which are extensively used in sensing applications. By design, dramatic increment of optical signals can be obtained and further applied to gas, refractive index and liquid sensing. Jiangtao Lv, Eunice Sok Ping Leong, Xiaoxiao Jiang, Shanshan Kou, Haitao Dai, Jiao Lin, Yan Jun Liu, and Guangyuan Si Copyright © 2015 Jiangtao Lv et al. All rights reserved. Application of Recycled Zero-Valent Iron Nanoparticle to the Treatment of Wastewater Containing Nitrobenzene Wed, 25 Nov 2015 06:29:16 +0000 Zero-valent iron (ZVI) was synthesized using iron oxide, a byproduct of pickling line at a steel work. ZVI with a mean particle size of 500 nm was synthesized. The reaction activity of the synthesized ZVI was much higher than commercial ZVI. When applied to the decomposition of nitrobenzene (NB), the ZVI particles underwent corrosion and passivation oxide film formation, resulting in particle size decrease. The NB decomposition rate increased with increasing ZVI dosage level and with decreasing pH. The solution pH increased monotonously with increasing reaction duration, whereas the aniline concentration showed a maximum at 50 min. Based on the GC/MS analysis, NB is presumed to be reduced into aniline via reductive intermediates such as azobenzene and azoxybenzene. When combined with a subsequent biological process, the synthesized ZVI will be able to decompose NB in wastewater effectively. Heon Lee, Byung-Hoon Kim, Young-Kwon Park, Sun-Jae Kim, and Sang-Chul Jung Copyright © 2015 Heon Lee et al. All rights reserved. Solution-Based High-Density Arrays of Dielectric Microsphere Structures for Improved Crystal Quality of III-Nitride Layers on Si Substrates Tue, 24 Nov 2015 12:41:05 +0000 The recent development of dielectric microsphere lithography has been able to open up new means of performing simple and easy patterning on the semiconductor surfaces. Here, we report uniform and high-density arrays of microspheres using a solution-based spin-coating method. The arrays of microspheres were used for etching mask to form the arrays of III-nitride microrods. By regrowing GaN layer on the microrod structures, high-quality GaN layer was achieved in terms of surface morphology as well as XRD characterization. To apply the advantages such as improved crystal quality and light extraction enhancement, light-emitting diodes (LEDs) were grown and then fabricated. The regrown LEDs with microspheres showed much improved optical output power and forward voltage characteristics in the same current injection. Therefore, we believe that this approach is quite useful for the development of high efficiency LEDs for future lighting. Ho-Jun Lee, Kye-Jin Lee, Kwang-Yong Choi, Jung-Hyun Eum, Dong-Kun Lee, Dong-Seon Lee, and Si-Young Bae Copyright © 2015 Ho-Jun Lee et al. All rights reserved. Optimization and Characterization of Artesunate-Loaded Chitosan-Decorated Poly(D,L-lactide-co-glycolide) Acid Nanoparticles Tue, 24 Nov 2015 12:16:15 +0000 The aim of this study was to optimize the formulation of artesunate-loaded chitosan- (CS-) decorated poly(D,L-lactide-co-glycolide) acid (PLGA) nanoparticles as well as evaluate their characteristics. CS-to-PLGA mass ratio, pH of CS solution, and experimental temperature were optimized using response surface methodology to understand their effects on size and zeta potential of nanoparticles. The optimized formulation showed the close agreement between predicted and experimental values (all bias below 5%). The presence of CS was confirmed by positive surface charge and Fourier transform infrared spectroscopy. A spherical-like shape of particles was observed in range of small size around 190 nm. This CS layer restricted initial burst release of drug from carriers in phosphate buffer of pH 6.8. In addition, CS-coated NPs enhanced the intracellular uptake, in vitro cytotoxicity, and apoptosis-induced nuclei behaviors compared with CS-uncoated NPs as well as free drug in MCF-7 and A549 cancer cells. Hoang Nhan Ho, Tuan Hiep Tran, Trong Bien Tran, Chul Soon Yong, and Chien Ngoc Nguyen Copyright © 2015 Hoang Nhan Ho et al. All rights reserved. Nanostructured Diamond-Like Carbon Films Grown by Off-Axis Pulsed Laser Deposition Tue, 24 Nov 2015 06:20:47 +0000 Nanostructured diamond-like carbon (DLC) films instead of the ultrasmooth film were obtained by pulsed laser ablation of pyrolytic graphite. Deposition was performed at room temperature in vacuum with substrates placed at off-axis position. The configuration utilized high density plasma plume arriving at low effective angle for the formation of nanostructured DLC. Nanostructures with maximum size of 50 nm were deposited as compared to the ultrasmooth DLC films obtained in a conventional deposition. The Raman spectra of the films confirmed that the films were diamond-like/amorphous in nature. Although grown at an angle, ion energy of >35 eV was obtained at the off-axis position. This was proposed to be responsible for subplantation growth of sp3 hybridized carbon. The condensation of energetic clusters and oblique angle deposition correspondingly gave rise to the formation of nanostructured DLC in this study. Seong Shan Yap, Chen Hon Nee, Seong Ling Yap, and Teck Yong Tou Copyright © 2015 Seong Shan Yap et al. All rights reserved. MOCVD Growth and Fabrication of High Power MUTC Photodiodes Using InGaAs-InP System Mon, 23 Nov 2015 12:37:33 +0000 We report charge-compensated modified uni-traveling-carrier photodiodes (MUTC-PDs) with high photocurrent and fast response, grown using liquid group-V precursor, in an AIXTRON MOCVD system. The liquid group-V precursors involve less toxicity with better decomposition characteristics. Device fabrication is completed with standard processing techniques with BCB passivation. DC and RF measurements are carried out using a single mode fiber at 1.55 μm. For a 24-μm-diameter device (with diode ideality factor of 1.34), the dark current is 32.5 nA and the 3-dB bandwidth is ≫20 GHz at a reverse bias of 5 V, which are comparable to the theoretical values. High photocurrent of over 150.0 mA from larger diameter (>60 μm) devices is obtained. The maximum DC responsivity at 1.55 μm wavelength is 0.51 A/W, without antireflection coating. These photodiodes play a key role in the progress of the future THz communication systems. Nandan Singh, Charles Kin Fai Ho, Guo Xin Tina, Manoj Kumar Chandra Mohan, Kenneth Eng Kian Lee, Hong Wang, and Huy Quoc Lam Copyright © 2015 Nandan Singh et al. All rights reserved. Surface Epitope Coverage Affects Binding Characteristics of Bisphenol-A Functionalized Nanoparticles in a Competitive Inhibition Assay Mon, 23 Nov 2015 09:29:52 +0000 The biomolecule interface is a key element in immunosensor fabrication, which can greatly influence the sensor performance. This paper explores the effects of surface epitope coverage of small molecule functionalized nanoparticle on the apparent affinity (avidity) of antibody in a competitive inhibition assay using bisphenol-A (BPA) as a model target. An unconventional two-antibody competitive inhibition ELISA (ci-ELISA) using thiolated BPA modified gold nanoparticles (cysBPAv-AuNP) as a competing reagent was devised for this study. It was shown that the antibody complexation with cysBPAv-AuNPs required a minimum number of surface epitopes on the nanoparticle to form a sufficiently strong interaction and reliable detection. The binding of cysBPAv-AuNP to anti-BPA antibodies, for limited antibody binding sites, was enhanced by a greater number of epitope-modified nanoparticles (cysBPAv-AuNP) as well as with higher epitope coverage. Increasing the molar concentration of epitope present in an assay enhanced the binding between anti-BPA antibodies and cysBPAv-AuNP. This implies that, to increase the limit of detection of a competitive inhibition assay, a reduced molar concentration of epitope should be applied. This could be achieved by either lowering the epitope coverage on each cysBPAv-AuNP or the assay molar concentration of cysBPAv-AuNP or both of these factors. Yang Lu, Joshua Richard Peterson, Erwann Luais, John Justin Gooding, and Nanju Alice Lee Copyright © 2015 Yang Lu et al. All rights reserved. VP6-SUMO Self-Assembly as Nanocarriers for Gastrointestinal Delivery Sun, 22 Nov 2015 07:56:59 +0000 High proteolytic degradation and poor absorption through epithelial barriers are major challenges to successful oral delivery of therapeutics. Nanoparticle platforms can enhance drug stability and extend the residence time in gastrointestinal (GI) tract. However, drug delivery systems are often inactivated in acidic environment of stomach or suffer poor absorption from intestinal cells due to the mucus layer. To overcome these issues we developed a drug delivery system constituted by a protein construct made by a Rotavirus capsid protein (VP6) and the small ubiquitin-like modifier SUMO. This chimeric construct allows specificity towards intestinal cells, the Rotavirus natural target, combined by an enhanced stability given by the eukaryotic protein transporter SUMO. Furthermore SUMO can act as a molecular switch that facilitates import/export of its ligand to the nucleus, the hypersensitive subcellular site target of many cell killing therapies. In this paper we show that SUMO-VP6 constructs self-assembly into stable nanocarriers. SUMO-VP6 nanocarriers display ideal features for drug delivery: a small size and high monodispersity, a high stability in different pH conditions and a high uptake in the nuclear and cytoplasmic compartment of intestinal cells. These features make SUMO-VP6 nanocarriers a promising novel system for oral delivery of poorly soluble drugs. V. Palmieri, F. Bugli, M. Papi, G. Ciasca, G. Maulucci, S. Galgano, A. Arcovito, M. Sanguinetti, and M. De Spirito Copyright © 2015 V. Palmieri et al. All rights reserved. Controlling Surface-Induced Nanocomposites by Lipoplexes for Enhanced Gene Transfer Sun, 22 Nov 2015 07:15:19 +0000 Surface-induced biomineralization represents a flexible approach to immobilizing DNA onto biomaterial surfaces for surface-mediated DNA delivery. Immobilized naked DNA is uniformly embedded in thin films of nanocomposites, which limits the internalization of DNA to some cell types, such as neuronal cells. In this study, DNA molecules were initially complexed with liposomes to form lipoplexes. Subsequently, these lipoplexes were immobilized onto a cell culture compatible surface through surface-induced biomineralization. Under all the conditions we examined, lipoplexes were efficiently immobilized onto the surface and formed lipoplex-nanocomposites. We have shown that the size of liposomes and the composition of mineralizing solutions have significant effects on the morphology and topology of nanocomposites and thus the organization and the intracellular levels of DNA. The transgene expression mediated by lipoplex-nanocomposites was greatly enhanced in neuronal cells compared to the immobilized naked DNA. Bingbing Sun and Hong Shen Copyright © 2015 Bingbing Sun and Hong Shen. All rights reserved. Direct Interband Light Absorption in Conical Quantum Dot Sun, 22 Nov 2015 06:50:19 +0000 In the framework of the adiabatic approximation, the energy states of electron as well as the direct light absorption are investigated in conical quantum dot. Analytical expressions for particle energy spectrum are obtained. The dependence of the absorption edge on geometrical parameters of conical quantum dot is obtained. Selection rules are revealed for transitions between levels with different quantum numbers. In particular, it is shown that for the radial quantum number transitions are allowed between the levels with the same quantum numbers, and any transitions between different levels are allowed for the principal quantum number. D. B. Hayrapetyan, A. V. Chalyan, E. M. Kazaryan, and H. A. Sarkisyan Copyright © 2015 D. B. Hayrapetyan et al. All rights reserved. Morphology Effect on the Kinetic Parameters and Surface Thermodynamic Properties of Ag3PO4 Micro-/Nanocrystals Thu, 19 Nov 2015 11:48:42 +0000 Considerable effort has been exerted using theoretical calculations to determine solid surface energies. Nanomaterials with high surface energy depending on morphology and size exhibit enhanced reactivity. Thus, investigating the effects of morphology, size, and nanostructure on the surface energies and kinetics of nanomaterials is important. This study determined the surface energies of silver phosphate (Ag3PO4) micro-/nanocrystals and their kinetic parameters when reacting with HNO3 by using microcalorimetry. This study also discussed rationally combined thermochemical cycle, transition state theory, basic theory of chemical thermodynamics with thermokinetic principle, morphology dependence of reaction kinetics, and surface thermodynamic properties. Results show that the molar surface enthalpy, molar surface entropy, molar surface Gibbs free energy, and molar surface energy of cubic Ag3PO4 micro-/nanocrystals are larger than those of rhombic dodecahedral Ag3PO4 micro-/nanocrystals. Compared with rhombic dodecahedral Ag3PO4, cubic Ag3PO4 with high surface energy exhibits higher reaction rate and lower activation energy, activation Gibbs free energy, activation enthalpy, and activation entropy. These results indicate that cubic Ag3PO4 micro-/nanocrystals can overcome small energy barrier faster than rhombic dodecahedral Ag3PO4 micro-/nanocrystals and thus require lower activation energy. Zai-Yin Huang, Xing-Xing Li, Zuo-Jiao Liu, Liang-Ming He, and Xue-Cai Tan Copyright © 2015 Zai-Yin Huang et al. All rights reserved. Effect of Au Precursor and Support on the Catalytic Activity of the Nano-Au-Catalysts for Propane Complete Oxidation Wed, 18 Nov 2015 09:56:43 +0000 Catalytic activity of nano-Au-catalyst(s) for the complete propane oxidation was investigated. The results showed that the nature of both Au precursor and support strongly influences catalytic activity of the Au-catalyst(s) for the propane oxidation. Oxidation state, size, and dispersion of Au nanoparticles in the Au-catalysts, surface area, crystallinity, phase structure, and redox property of the support are the key aspects for the complete propane oxidation. Among the studied Au-catalysts, the -Ce catalyst is found to be the most active catalyst. Arshid M. Ali, Muhammad A. Daous, Ahmed Arafat, Abdulraheem A. AlZahrani, Yahia Alhamed, Abudula Tuerdimaimaiti, and Lachezar A. Petrov Copyright © 2015 Arshid M. Ali et al. All rights reserved. Size Control of Alloyed Cu-In-Zn-S Nanoflowers Wed, 18 Nov 2015 09:33:42 +0000 Uniform, alloyed Cu-In-Zn-S nanoflowers with sizes of  nm and  nm composed of aggregated 4.1 nm and 5.6 nm primary crystallites, respectively, were obtained in a one-pot, heat-up reaction between copper, indium, and zinc acetate with tert-dodecanethiol in the presence of trioctylphosphine oxide. Larger aggregates were obtained by diluting tert-dodecanethiol with oleylamine, which lowered the reactivity of the indium and zinc precursors and led to the formation of copper rich particles. The thermal decomposition of tert-dodecanethiol stabilizing the primary crystallites induced their agglomeration, while the presence of trioctylphosphine oxide on the surface of the nanoflowers provided them with colloidal stability and prevented them from further aggregation. Björn Kempken, Alexandra Erdt, Jürgen Parisi, and Joanna Kolny-Olesiak Copyright © 2015 Björn Kempken et al. All rights reserved. Supramolecular Encapsulation of Vitamin B6 by Macrocyclic Nanocontainer Cucurbit[7]uril Wed, 18 Nov 2015 07:45:00 +0000 A pharmaceutically and biologically relevant molecule, pyridoxine hydrochloride (vitamin B6), was encapsulated inside the cavity of a molecular container, cucurbit[]uril (CB[]), in aqueous solution. The CB[] based “nanocapsule” of vitamin B6 has been investigated for the first time, via 1H NMR and UV-visible spectroscopic titrations (including Job’s plot) and ab initio molecular modeling. The results have demonstrated that vitamin B6 forms stable host-guest complexes within CB[] in 1 : 1 stoichiometry, with a binding affinity of  M−1. Such a nanocapsule could potentially find application in vitamin B6 formulation for the purpose of enhancing the stability, absorption, and delivery of this important vitamin. Wanying Li, Shengke Li, Ian W. Wyman, Donal H. Macartney, Qingwen Zhang, Ying Zheng, and Ruibing Wang Copyright © 2015 Wanying Li et al. All rights reserved. Surge-Resistant Nanocomposite Enameled Wire Using Silica Nanoparticles with Binary Chemical Compositions on the Surface Wed, 18 Nov 2015 06:26:23 +0000 We developed polyesterimide (PEI) nanocomposite enameled wires using surface-modified silica nanoparticles with binary chemical compositions on the surface. The modification was done using silanes assisted by ultrasound, which facilitated high density modification. Two different trimethoxysilanes were chosen for the modification on the basis of resemblance of chemical compositions on the silica surface to PEI varnish. The surface-modified silica was well dispersed in PEI varnish, which was confirmed by optical observation and viscosity measurement. The glass transition temperature of the silica-PEI nanocomposite increased with the silica content. The silica-dispersed PEI varnish was then used for enameled wire fabrication. The silica-PEI nanocomposite enameled wire exhibited a much longer lifetime compared to that of neat PEI enameled wire in partial discharge conditions. Jeseung Yoo, Yongbeom Kim, Suyong Kwon, Joohyun Lee, and Young-Soo Seo Copyright © 2015 Jeseung Yoo et al. All rights reserved. In Vitro Hemocompatibility and Cytotoxicity Evaluation of Halloysite Nanotubes for Biomedical Application Tue, 17 Nov 2015 14:14:03 +0000 Halloysite nanotubes (HNTs), due to their unique structures and properties, may play an important role in biomedical applications. In vitro test is usually conducted as a preliminary screening evaluation of the hemocompatibility and cytotoxicity of HNTs for its short term consuming, convenience, and less expense. In this work, HNTs were processed with anticoagulated rabbit blood to detect its blood compatibility. The result of hemolysis test shows that the hemolysis ratios are below 0.5%, indicating nonhemolysis of HNTs. Plasma recalcification time suggests that HNTs are dose-dependently contributing to blood coagulation in platelet poor plasma (PPP). The effect of platelet activation caused by HNTs was also examined by scanning electron microscopy (SEM). Meanwhile, HNTs were labeled with fluorescein isothiocyanate (FITC) to observe its intracellular distribution in A549 cells under confocal microscopy. CCK-8 test and TUNEL test of HNTs at different concentration levels were performed in vitro, respectively. Therefore, the potential usage of HNTs in medicine may be very meaningful in oral dosing, dermal application, dental uses, or medical implants. Hao-Yang Liu, Lei Du, Yan-Teng Zhao, and Wei-Qun Tian Copyright © 2015 Hao-Yang Liu et al. All rights reserved. Graphene Nanoplatelets in Epoxy System: Dispersion, Reaggregation, and Mechanical Properties of Nanocomposites Tue, 17 Nov 2015 12:54:58 +0000 The use of graphene nanocomposites in advanced applications has attracted much attention in recent years. However, in order to substitute traditional epoxy reinforcements with graphene, there are still some issues like dispersion, homogenization, and reaggregation. In this paper, graphene bundles dispersed in two-component epoxy system by bath sonication, dispersion state, and reaggregation behavior of graphene in this system have been studied. Light transmittance in ultraviolet-visible spectroscopy has been used to quantify the reaggregation by a series of controlled experiments. After 18 mins sonication of 0.005 wt% graphene dispersion at 20°C, the light transmittance decreased from 68.92% to 54.88% in liquid epoxy and decreased from 72.80% to 46.42% in hardener; while increasing the temperature from 20°C to 60°C, the light transmittance in liquid epoxy decreased from 65.96% to 53.21% after 6 mins sonication. With the incorporation of 0.3 wt% graphene, the tensile strength of nanocomposites increased from 57.2 MPa to 64.4 MPa and the storage modulus increased from 1.66 GPa to 2.16 GPa. The results showed that the dispersion state depends on the function of sonication time and temperature, and graphene has a significant reinforcement effect on epoxy. Jiacheng Wei, Rasheed Atif, Thuc Vo, and Fawad Inam Copyright © 2015 Jiacheng Wei et al. All rights reserved. Interface Dependent Plasmon Induced Enhancement in Dye-Sensitized Solar Cells Using Gold Nanoparticles Tue, 17 Nov 2015 12:34:37 +0000 We report a study on plasmon-induced photoelectrochemistry from gold nanoparticles incorporated in dye-sensitized solar cells, assembled in two different configurations: TiO2//Dye and TiO2/Dye/. Although the presence of the plasmonic material resulted in enhanced photocurrent and energy conversion efficiency, a decrease of fill factor was observed. Electrical modeling of the solar cells was performed and revealed a simultaneous decrease of parallel resistance and increase of series resistance, related to the presence of gold nanoparticles. The enhancement in photocurrent was related to a combination of strong plasmon-induced electric fields and light scattering, which overcome the loss in electrical properties. In addition, the overall increase in efficiency was found dependent on the interface where the plasmonic material is placed. The highest efficiency obtained from TiO2//Dye was attributed to a larger density of photoexcited electrons allowed to be transferred towards conduction band of TiO2. Matheus Costa de Oliveira, André Luis Silveira Fraga, Anderson Thesing, Rocelito Lopes de Andrade, Jacqueline Ferreira Leite Santos, and Marcos José Leite Santos Copyright © 2015 Matheus Costa de Oliveira et al. All rights reserved. Layer-by-Layer Self-Assembled Ferrite Multilayer Nanofilms for Microwave Absorption Tue, 17 Nov 2015 08:23:55 +0000 We demonstrate a simple method for fabricating multilayer thin films containing ferrite (Co0.5Zn0.5Fe2O4) nanoparticles, using layer-by-layer (LbL) self-assembly. These films have microwave absorbing properties for possible radar absorbing and stealth applications. To demonstrate incorporation of inorganic ferrite nanoparticles into an electrostatic-interaction-based LbL self-assembly, we fabricated two types of films: (1) a blended three-component LbL film consisting of a sequential poly(acrylic acid)/oleic acid-ferrite blend layer and a poly(allylamine hydrochloride) layer and (2) a tetralayer LbL film consisting of sequential poly(diallyldimethylammonium chloride), poly(sodium-4-sulfonate), bPEI-ferrite, and poly(sodium-4-sulfonate) layers. We compared surface morphologies, thicknesses, and packing density of the two types of ferrite multilayer film. Ferrite nanoparticles (Co0.5Zn0.5Fe2O4) were prepared via a coprecipitation method from an aqueous precursor solution. The structure and composition of the ferrite nanoparticles were characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, transmission electron microscopy, and scanning electron microscopy. X-ray diffraction patterns of ferrite nanoparticles indicated a cubic spinel structure, and energy dispersive X-ray spectroscopy revealed their composition. Thickness growth and surface morphology were measured using a profilometer, atomic force microscope, and scanning electron microscope. Jiwoong Heo, Daheui Choi, and Jinkee Hong Copyright © 2015 Jiwoong Heo et al. All rights reserved. Preparation of Cefquinome Nanoparticles by Using the Supercritical Antisolvent Process Mon, 16 Nov 2015 16:53:21 +0000 The supercritical antisolvent process was used successfully to prepare nanoparticles of cefquinome. These particles were observed by scanning electron microscope (SEM) and their average diameter was measured by laser particle size analyzer. In the experiments, dimethyl sulfoxide (DMSO) was selected as solvent to dissolve cefquinome sulfate. It was confirmed by orthogonal experiments that the concentration of solution was the primary factor in this process followed by feeding speed of solution, precipitation pressure, and precipitation temperature. Moreover, the optimal conditions of preparing nanoparticles of cefquinome by supercritical antisolvent process were that solution concentration was 100 mg/mL, solution flow speed was 1.5 mL/min, operating pressure was 13 Mpa, and operating temperature was 33°C. Confirmatory experiment was conducted under this condition. It was found that the appearance of particles was flakes and the average diameter of particles was 0.71 microns. Finally, influence law of individual factor on particle size was investigated by univariate analysis. Xiao Kefeng, Wang Weiqiang, Hu Dedong, Hao Zhihui, Qu Yanpeng, and Liu Yan Copyright © 2015 Xiao Kefeng et al. All rights reserved.