Journal of Nanomaterials https://www.hindawi.com The latest articles from Hindawi © 2017 , Hindawi Limited . All rights reserved. Ecobiophysical Aspects on Nanosilver Biogenerated from Citrus reticulata Peels, as Potential Biopesticide for Controlling Pathogens and Wetland Plants in Aquatic Media Thu, 29 Jun 2017 00:00:00 +0000 http://www.hindawi.com/journals/jnm/2017/4214017/ In recent years, a considerable interest was paid to ecological strategies in management of plant diseases and plant growth. Metallic nanoparticles (MNPs) gained considerable interest as alternative to pesticides due to their interesting properties. Green synthesis of MNPs using plant extracts is very advantageous taking into account the fact that plants are easily available and eco-friendly and possess many phytocompounds that help in bioreduction of metal ions. In this research work, we phytosynthesized AgNPs from aqueous extract of Citrus reticulata peels, with high antioxidant, antibacterial, and antifungal potential. These “green” AgNPs were characterized by modern biophysical methods (absorption and FTIR spectroscopy, AFM, and zeta potential measurements). The nanobioimpact of Citrus-based AgNPs on four invasive wetland plants, Cattail (Typha latifolia), Flowering-rush (Butomus umbellatus), Duckweed (Lemna minor), and Water-pepper (Polygonum hydropiper), was studied by absorption spectroscopy, by monitoring the spectral signature of chlorophyll. The invasive plants exhibited different behavior under AgNP stress. Deep insights were obtained from experiments conducted on biomimetic membranes marked with chlorophyll a. Our results pointed out the potential use of Citrus-based AgNPs as alternative in controlling pathogens in aqueous media and in management of aquatic weeds growth. Marcela Elisabeta Barbinta-Patrascu, Nicoleta Badea, Camelia Ungureanu, Stefan Marian Iordache, Marioara Constantin, Violeta Purcar, Ileana Rau, and Cristian Pirvu Copyright © 2017 Marcela Elisabeta Barbinta-Patrascu et al. All rights reserved. Photoregulation of Gold Nanoparticles Stabilized in a Diacetylenic Nanocapsule Wed, 28 Jun 2017 00:00:00 +0000 http://www.hindawi.com/journals/jnm/2017/2539520/ The results of releasing a drug in a burst are unpredictable and one of the inherent drawbacks of using nanocarriers. Here, photoresponsive cationic gold nanoparticles to stabilize diacetylenic nanocapsules enabling photoregulated release of payloads are reported. The fabrication of these nanocapsules relied on an electrostatic interaction of a negatively charged diacetylenic core and a positively charged gold nanoparticle shell. Gold nanoparticles with photoresponsive ligands on their surfaces act as both hydrophobic core stabilizers and gatekeepers of the nanocapsules, while their polydiacetylene cores serve as hydrophobic drug carriers that can be tuned using UV irradiation. The morphology of nanocapsules was analyzed using TEM and dynamic light scattering. The resultant nanocapsules had a spherical shape with an average diameter of 152.9 ± 6.7 nm. Upon UV irradiation, the nanocapsules lost their integrity and an encapsulated model compound was released through diffusion. The release of a hydrophobic molecule was irradiation time dependent and thereby controllable. This light-triggered release provides an alternative strategy for controlled drug delivery. Saowalak Somjid, Apiwat Chompoosor, Somdej Kanokmedhakul, and Saowapak Teerasong Copyright © 2017 Saowalak Somjid et al. All rights reserved. Effect of Varying the Semiconducting/Metallic Tube Ratio on the Performance of Mixed Single-Walled Carbon Nanotube Network Gas Sensors Wed, 28 Jun 2017 00:00:00 +0000 http://www.hindawi.com/journals/jnm/2017/8761064/ The sensing properties of mixed networks consisting of semiconducting and metallic single-walled carbon nanotubes (SWCNTs) have been found to largely vary depending on the ratio of semiconducting to metallic tubes. Solution-deposited 99% semiconductor-enriched nanotube networks exhibited a sensitivity of 1.908%/ppm, whereas the unenriched 66% and 90% enriched samples exhibited a sensitivity of 0.027%/ppm and 0.113%/ppm, respectively. These results suggest that it is extremely important to minimize the metallic pathways to achieve high sensitivity. After an oxygen plasma treatment, the unenriched 66% sample exhibited a 526% increase in sensitivity (0.142%/ppm) compared to the untreated one, whereas the 90% device demonstrated a sensitivity of 1.521%/ppm, which corresponds to an improvement in the sensitivity of 13.5 times the pristine 90% sample. In addition, the plasma-treated sensors exhibited a much faster response time than the untreated one. The significant improvement in the performance of the highly enriched network sensors was explained by the large increase in the anchoring sites for ammonia molecules on the surface of the semiconducting single-walled CNTs and the faster charge transfer from absorbed molecules. Sung Joon Min, Jin Woong Kim, Joon Hyub Kim, Joon Hyock Choi, Chan Won Park, and Nam Ki Min Copyright © 2017 Sung Joon Min et al. All rights reserved. Sodium Hypochlorite as Fluorotic Dentin Pretreatment of Two-Step Self-Etch Adhesive with Silver Nanoparticle: Atomic Force Microscope and Adhesive Microtensile Bond Strength Evaluation Tue, 27 Jun 2017 09:04:57 +0000 http://www.hindawi.com/journals/jnm/2017/1381929/ The objective of this work was to evaluate the effect of pretreatment with commercial sodium hypochlorite, 5.25%, with a self-etch adhesive (Optibond Versa) in its original formula and with the incorporation of silver nanoparticles (NaAg) on fluorotic dentin. 240 human molars were classified according to fluorosis severity with Thylstrup-Fejerskov Index (TFI) and subdivided into three study subgroups according to the adhesive technique: () self-etch (SE) control subgroup; () NaOCl/SE subgroup; () NaOCl/SE + NaAg subgroup. The nanostructural characteristics were observed by AFM, μTBS was tested, and hybrid layer formation was observed by SEM. One-way analyses of variance (ANOVA) and Tukey-Kramer post hoc tests were used. No statistically significant differences were found in roughness values in any of the subgroups and subgroups studied. Remnants of smear layer were detected in areas devoid of resin tags in SEM images of samples bonded with subgroup 2, in contrast to subgroup 3. No statistically significant difference between any of the results was found in μTBS and a greater number of adhesive failures were observed. The results show that the pretreatment technique of 5.25% NaOCl and the incorporation of NaAg to the self-adhesive system do not produce a surface more adequate for a better adhesion. Ana-Josefina Monjarás-Ávila, Norma-Verónica Zavala-Alonso, Gabriel Alejandro Martínez-Castañón, Nuria Patiño-Marín, Daniel Silva-Herzog Flores, and Facundo Ruíz Copyright © 2017 Ana-Josefina Monjarás-Ávila et al. All rights reserved. H2Ti3O7 Nanotubes Decorated with Silver Nanoparticles for Photocatalytic Degradation of Atenolol Tue, 27 Jun 2017 08:32:17 +0000 http://www.hindawi.com/journals/jnm/2017/9610419/ The photocatalytic degradation/adsorption process of the β-blocker atenolol (ATL) under UV irradiation is described using two types of silver decorated catalysts: silver/titania and silver/titanates. The silver ions were reduced on the surface of TiO2-P25-Degussa using gallic acid. Silver/titanates were prepared by a microwave-assisted hydrothermal method using the silver/titania as the starting material to obtain the hydrogen titanate (H2Ti3O7) structure with tubular morphology. These materials were characterized by X-ray diffraction, UV-Vis spectroscopy, N2 physisorption, temperature programmed reduction, TEM, and FTIR spectroscopy. During the photocatalytic process, the ATL molecules were completely converted to amino-diol byproducts. It is the first time that these materials have been applied during the photocatalytic process in the degradation of pharmaceuticals products. The success of the silver nanoparticles (2 nm) consists of the homogeneous distribution over the surface of titanate nanotubes inhibiting the hole/electron recombination promoting the oxidation process. The Ag@H2Ti3O7 with a concentration of silver as 1.0% shows the highest adsorption/degradation of ATL than the Ag@TiO2 and the P25-Degussa. The great performance in the reuse test consists in the strong attachment of the silver nanoparticles on the titanium surface that inhibits the silver lixiviation during the photocatalytic tests. Mariana Hinojosa-Reyes, Roberto Camposeco-Solís, Facundo Ruiz, Nereyda Niño Martínez, Vicente Rodríguez González, and M. E. Compeán-Jasso Copyright © 2017 Mariana Hinojosa-Reyes et al. All rights reserved. The Virtuous CO2 Circle or the Three Cs: Capture, Cache, and Convert Wed, 21 Jun 2017 06:22:35 +0000 http://www.hindawi.com/journals/jnm/2017/6594151/ It is not the first time in human history, nor will it be the last for that matter, that a collective problem calls for a collective response. Climate change fueled by greenhouse emissions affects humankind alike. Despite the disagreement among policymakers and scientists on the severity of the issue, the truth is that the problem remains. A broad look at different technologies being used today in different fields has led to the idea of bringing them together in an attempt to offer a viable solution to reducing anthropogenic CO2. The following paper describes how the nanotechnologies, available or soon to be available, would make CO2 capture, cache, and conversion (coined the three Cs) a valid way for achieving a more sustainable energy society. Authors also set out to highlight with this work how knowledge transfer is instrumental in the development of technology and how methodical assessment of crossovers can expedite research when time plays against us. Sergio Bocchini, Carlos Castro, Matteo Cocuzza, Sergio Ferrero, Giulio Latini, Alberto Martis, Fabrizio Pirri, Luciano Scaltrito, Vera Rocca, Francesca Verga, and Dario Viberti Copyright © 2017 Sergio Bocchini et al. All rights reserved. Nanofibrillated Cellulose from Appalachian Hardwoods Logging Residues as Template for Antimicrobial Copper Mon, 19 Jun 2017 00:00:00 +0000 http://www.hindawi.com/journals/jnm/2017/2102987/ TEMPO nanofibrillated cellulose (TNFC) from two underutilized Appalachian hardwoods, Northern red oak (Quercus rubra) and yellow poplar (Liriodendron tulipifera), was prepared to determine its feasibility to be used as template for antimicrobial metallic copper particles. In addition, a comparison of the TNFC from the two species in terms of their morphological, chemical, thermal, and mechanical properties was also performed. The woody biomass was provided in the form of logging residue from Preston County, West Virginia. A traditional kraft process was used to produce the pulp followed by a five-stage bleaching. Bleached pulps were then subjected to a TEMPO oxidation process using the TEMPO/NaBr/NaClO system to facilitate the final mechanical fibrillation process and surface incorporation of metallic copper. The final TNFC diameters for red oak and yellow poplar presented similar dimensions,  nm and  nm, respectively. The TNFC films fabricated from both species exhibited no statistical differences in both Young’s modulus and the final strength properties. Likely, after the TEMPO oxidation process both species exhibited similar carboxyl group content, of approximately 0.8 mmol/g, and both species demonstrated excellent capability to incorporate antimicrobial copper on their surfaces. Masoumeh Hassanzadeh, Ronald Sabo, Alan Rudie, Richard Reiner, Roland Gleisner, and Gloria S. Oporto Copyright © 2017 Masoumeh Hassanzadeh et al. All rights reserved. Magnetic-Field-Enhanced Morphology of Tin Oxide Nanomaterials for Gas Sensing Applications Sun, 18 Jun 2017 00:00:00 +0000 http://www.hindawi.com/journals/jnm/2017/4396723/ We studied the effect of an external magnetic field (up to 0.31 T) on the growth of SnO2 nanowires fabricated using the horizontal vapor phase growth (HPVG) technique. The morphology of the nanowires was characterized by using scanning electron microscopy (SEM), and the chemical composition was characterized by energy dispersive X-ray (EDX) analysis. We found that the length of nanowires was significantly enhanced by the application of EMF. The aspect ratio, as well as the density of the fabricated nanowires, increased with increasing magnetic field intensity. Although the physics behind the morphology enhancement of the nanowires under magnetic field is still being investigated, nevertheless, we demonstrated that the magnetic field could be used as a key parameter to control the morphology of tin oxide nanomaterials grown via HPVG technique. The magnetically enhanced nanowires were used in the development of a gas sensor and were found to be sensitive to hydrogen sulfide gas and the headspace gas emitted by spoiling meat. Jonathan C. Briones, Gwen Castillon, Michael P. Delmo, and Gil Nonato C. Santos Copyright © 2017 Jonathan C. Briones et al. All rights reserved. Investigating Visible-Photocatalytic Activity of MoS2/TiO2 Heterostructure Thin Films at Various MoS2 Deposition Times Thu, 15 Jun 2017 09:34:20 +0000 http://www.hindawi.com/journals/jnm/2017/3197540/ MoS2/TiO2 heterostructure thin films were fabricated by sol-gel and chemical bath deposition methods. Crystal structure, surface morphology, chemical states of all elements, and optical property of the obtained thin films were characterized by using X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and UV-Vis spectroscopy techniques, respectively. Photocatalytic activity of all thin films was evaluated by measuring decomposition rate of methylene blue solution under visible light irradiation. The results indicate that ultrathin MoS2 film on TiO2-glass substrate improves photocatalytic activity of TiO2 in the visible light due to the efficient absorption of visible photon of MoS2 few layers and the transfer of electrons from MoS2 to TiO2. All MoS2/TiO2 heterostructure thin films exhibit higher visible light photocatalytic activity than that of pure MoS2 and TiO2 counterparts. The best MoS2/TiO2 heterostructure thin film at MoS2 layer deposition time of 45 minutes can decompose about 60% MB solution after 150 minutes under visible light irradiation. The mechanism of the enhancement for visible-photocatalytic activity of MoS2/TiO2 heterostructure thin film was also discussed. Hang Nguyen Thai Phung, Van Nguyen Khanh Tran, Lam Thanh Nguyen, Loan Kieu Thi Phan, Phuong Ai Duong, and Hung Vu Tuan Le Copyright © 2017 Hang Nguyen Thai Phung et al. All rights reserved. Study of Static Magnetic Properties of Transformer Oil Based Magnetic Fluids for Various Technical Applications Using Demagnetizing Field Correction Thu, 15 Jun 2017 00:00:00 +0000 http://www.hindawi.com/journals/jnm/2017/5407679/ Static magnetization data of eight transformer oil based magnetic fluid samples, with saturation magnetization ranging in a large interval from 9 kA/m to 90 kA/m, have been subjected to the demagnetizing field correction. Using the tabulated demagnetization factors and the differential magnetic susceptibility of the samples, the values of the radial magnetometric demagnetization factor were obtained in the particular case of VSM880 magnetometer. It was found that the demagnetizing field correction keeps the saturation magnetization values unchanged, but instead the initial magnetic susceptibility of the magnetic fluid samples varies widely. The mean magnetic diameter, obtained through magnetogranulometry from the measured data, is higher than that obtained from the corrected ones and the variation rate increases with the magnetic particle volume fraction growth. Oana Maria Marinica Copyright © 2017 Oana Maria Marinica. All rights reserved. Research on the Thermal Aging Behaviors of LDPE/TiO2 Nanocomposites Wed, 14 Jun 2017 08:56:49 +0000 http://www.hindawi.com/journals/jnm/2017/5048382/ The ability of antithermal aging of LDPE/TiO2 nanocomposites was investigated through SEM, FTIR, DSC, and dielectric properties in this paper. The results of SEM images showed that the thermal aging had a significant influence on the structure of Pure-LDPE and LDPE/TiO2 samples. The measurement of FTIR showed that the content of hydroxyl and carboxyl increased with thermal aging, but the time of emerging aging characteristic peaks for the LDPE/TiO2 samples was delayed. The DSC measurement indicated that filling TiO2 nanoparticles changed the crystallization behavior of LDPE, played a role of heterogeneous nucleation during the process of recrystallization, and improved the crystallinity of LDPE/TiO2. Similarly, the aged LDPE/TiO2 samples had lower permittivity and dissipation factor compared to the aged Pure-LDPE samples. All the results had indicated the LDPE/TiO2 samples had the significant ability of antithermal aging, especially the LDPE/TiO2-0.5 samples with good dispersion of nanoparticles. A new model was proposed to illustrate the antithermal aging behaviors of LDPE/TiO2 samples, which shows that the TiO2 nanoparticles play a role of “crosslinking points” between LDPE molecular chains, increasing the density of crystal structure and reducing oxygen diffusion into materials to break molecular structure. Jun Liu, Youyuan Wang, Kun Xiao, and Zhanxi Zhang Copyright © 2017 Jun Liu et al. All rights reserved. Synthesis and Characterization of Low Loss Dielectric Ceramics Prepared from Composite of Titanate Nanosheets with Barium Ions Wed, 14 Jun 2017 00:00:00 +0000 http://www.hindawi.com/journals/jnm/2017/1351085/ We report a strategy for preparing barium titanate precursor, being the composite of titanate nanosheets (TN) with barium ions (Ba-TN), which subjected to step sintering allows obtaining TiO2 rich barium titanate ceramics of stoichiometry BaTi4O9 or Ba2Ti9O20. These compounds are important in modern electronics due to their required dielectric properties and grains’ size that can be preserved in nanometric range. The morphology studies, structural characterization, and dielectric investigations were performed simultaneously in each step of Ba-TN calcinations in order to properly characterize type of obtained ceramic, its grains’ morphology, and dielectric properties. The Ba-TN precursor can be sintered at given temperatures, so that its dielectric permittivity can be tuned between 25 and 42 with controlled temperature coefficients that change from negative 32 ppm/°C for Ba-TN sintered at 900°C up to positive 37 ppm/°C after calcination at 1300°C. XRD analysis and Raman investigations performed for the Ba-TN in the temperature range of °C showed that below 1100°C we obtained as a main phase BaTi4O9, whereas the higher calcinations temperature transformed Ba-TN into Ba2Ti9O20. Taking into account trend of device miniaturization and nanoscopic size requirements, temperatures of 900°C and 1100°C seem to be an optimal condition for Ba-TN precursor calcinations that guarantee the satisfactory value of dielectric permittivity ( and 32) and ceramic grains with a mean size of ~180 nm and ~550 nm, respectively. Aleksandra Wypych-Puszkarz, Izabela Bobowska, Angelika Wrzesinska, Agnieszka Opasinska, Waldemar Maniukiewicz, Piotr Wojciechowski, and Jacek Ulanski Copyright © 2017 Aleksandra Wypych-Puszkarz et al. All rights reserved. Mechanisms of Cellular Effects Directly Induced by Magnetic Nanoparticles under Magnetic Fields Tue, 13 Jun 2017 09:34:25 +0000 http://www.hindawi.com/journals/jnm/2017/1564634/ The interaction of magnetic nanoparticles (MNPs) with various magnetic fields could directly induce cellular effects. Many scattered investigations have got involved in these cellular effects, analyzed their relative mechanisms, and extended their biomedical uses in magnetic hyperthermia and cell regulation. This review reports these cellular effects and their important applications in biomedical area. More importantly, we highlight the underlying mechanisms behind these direct cellular effects in the review from the thermal energy and mechanical force. Recently, some physical analyses showed that the mechanisms of heat and mechanical force in cellular effects are controversial. Although the physical principle plays an important role in these cellular effects, some chemical reactions such as free radical reaction also existed in the interaction of MNPs with magnetic fields, which provides the possible explanation for the current controversy. It is anticipated that the review here could provide readers with a deeper understanding of mechanisms of how MNPs contribute to the direct cellular effects and thus their biomedical applications under various magnetic fields. Linjie Chen, Changyou Chen, Pingping Wang, and Tao Song Copyright © 2017 Linjie Chen et al. All rights reserved. Incorporation of Boron Atoms on Graphene Grown by Chemical Vapor Deposition Using Triisopropyl Borate as a Single Precursor Tue, 13 Jun 2017 07:16:59 +0000 http://www.hindawi.com/journals/jnm/2017/9298637/ We synthesized single-layer graphene from a liquid precursor (triisopropyl borate) using a chemical vapor deposition. Optical microscopy, scanning electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy measurements were used for the characterization of the samples. We investigated the effects of the processing temperature and time, as well as the vapor pressure of the precursor. The core-level XPS spectra revealed the presence of boron atoms incorporated into substitutional sites. This result, corroborated by the observed upshift of both G and 2D bands in the Raman spectra, suggests the p-doping of single-layer graphene for the samples prepared at 1000°C and pressures in the range of 75 to 25 mTorr of the precursor vapor. Our results show that, in optimum conditions for single-layer graphene growth, that is, 1000°C and 75 mTorr for 5 minutes, we obtained samples presenting the coexistence of pristine graphene with regions of boron-doped graphene. E. C. Romani, D. G. Larrude, M. E. H. Maia da Costa, G. Mariotto, and F. L. Freire Jr. Copyright © 2017 E. C. Romani et al. All rights reserved. Thermal Transport and Rectification Properties of Bamboo-Like SiC Polytypes Nanowires Mon, 12 Jun 2017 00:00:00 +0000 http://www.hindawi.com/journals/jnm/2017/5038978/ Bamboo-like SiC nanowires (NWs) have specific geometric shapes, which have the potential to suppress thermal conductivity by phonon boundary scattering. In this work, phonon transport behaviors in the 3C-SiC, 4H-SiC, and 6H-SiC crystal lattices are studied by the Monte Carlo (MC) method, including impurity scattering, boundary scattering, and Umklapp scattering. Phonon relaxation times for Umklapp (U) scattering for the above three SiC polytypes are calculated from the respective phonon spectra, which have not been reported in the literature. Diffuse boundary scattering and thermal rectification with different aspect ratios are also studied at different temperatures. It is found that the thermal conductivities of the bamboo-like SiC polytypes can be lowered by two orders of magnitude compared with the bulk values by contributions from boundary scattering. Compared with bamboo-like 4H-SiC and 6H-SiC NWs, 3C-SiC has the largest U scattering relaxation rate and boundary scattering rate, which leads to its lowest thermal conductivities. The thermal conductivity in the positive direction is larger than that in the negative direction because of its lower boundary scattering relaxation rate. Zan Wang Copyright © 2017 Zan Wang. All rights reserved. Luminomagnetic Silica-Coated Heterodimers of Core/Shell FePt/Fe3O4 and CdSe Quantum Dots as Potential Biomedical Sensor Sun, 11 Jun 2017 00:00:00 +0000 http://www.hindawi.com/journals/jnm/2017/2160278/ We report the synthesis of a new multifunctional nanomaterial based on silica-coated FePt/Fe3O4-CdSe heteronanostructures, combining luminescent and magnetic properties in a promising bifunctional sensor for biomedical applications. Spherical Fe3O4-coated FePt (FePt/Fe3O4) superparamagnetic nanoparticles (10.8 ± 1.5 nm) with high saturation magnetization and controlled size and shape were obtained using thermal decomposition coupled with seed-mediated growth method. Luminescent property was added to the nanomaterial by using the FePt/Fe3O4 magnetic core as seed and growing the CdSe quantum dots (2.7 ± 0.6 nm) onto its surface in a heterodimer-like structure using the hot-injection approach. The FePt/Fe3O4-CdSe luminomagnetic heteronanostructures were coated with silica shell using the reverse-micelle microemulsion route to avoid solvent-quenching effects. After silica coating, the water-dispersible heteronanostructures showed a diameter of 25.3 ± 2 nm, high colloidal stability, magnetic saturation of around 11 emu g−1, and photoluminescence in the blue-green region, as expected for potential bifunctional platform in biomedical applications. The saturation magnetization of heteronanostructures can be increased to 28 emu g−1 by annealing at 550°C due to the presence of the FePt phase. Caio Guilherme Secco de Souza, João Batista Souza Jr., Watson Beck Jr., and Laudemir Carlos Varanda Copyright © 2017 Caio Guilherme Secco de Souza et al. All rights reserved. Role of pH in the Aqueous Phase Reactivity of Zerovalent Iron Nanoparticles with Acid Orange 7, a Model Molecule of Azo Dyes Sun, 11 Jun 2017 00:00:00 +0000 http://www.hindawi.com/journals/jnm/2017/2749575/ The effect of both pH and surface oxidation of nanoparticles is studied on the interaction between a commercial slurry of Nanoscale Zerovalent Iron (NZVI) and the azo dye Acid Orange 7 (AO7). NZVI is a reducing agent used for the degradation of several pollutants, including azo dyes: during pollutant degradation, it undergoes progressive oxidation and dissolution. Though it is generally acknowledged that NZVI consists of core-shell nanoparticles, where the core of metallic iron is covered by shell, it still remains a poorly defined system. In this work, the solid fraction recovered by filtration and drying was characterized by means of XRD diffraction with Rietveld refinement, N2 isotherms at 77 K, FE-SEM and TEM observation, EDX analysis, and IR spectroscopy. Powders were obtained from both the parent slurry and the same slurry pretreated with HCl in order to remove shell, finally reactivating the nanoparticles. The aforementioned physicochemical characterization allowed figuring out some correlations between the properties of the studied nanomaterial and the processes occurring when it is in contact with AO7 in aqueous phase. The type of interaction occurring within the NZVI/AO7 system (adsorption and type of redox reactions) strongly depends not only on the pH of the starting solution, but also on the surface oxidation of the nanoparticles. F. S. Freyria, S. Esposito, M. Armandi, F. Deorsola, E. Garrone, and B. Bonelli Copyright © 2017 F. S. Freyria et al. All rights reserved. Development of Stabilized Magnetite Nanoparticles for Medical Applications Sun, 11 Jun 2017 00:00:00 +0000 http://www.hindawi.com/journals/jnm/2017/6514659/ We report a facile method to synthesize magnetite nanoparticles with mesoporous structure by coprecipitation method using different stabilizing agents like salicylic acid, glutamic acid, and trichloroacetic acid. The stabilizing agents were used to prevent the aggregation of the magnetite nanocrystals and to obtain stable nanostructures even in the biological environment. The structure and morphology of magnetic nanocrystals were determined using X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, Brunauer-Emmett-Teller (BET) analysis, infrared (IR) spectra, scanning and transmission electron microscopy (SEM and TEM), high-resolution transmission electron microscopy (HRTEM), and selected area electron diffraction (SAED). The results reveal important differences between these magnetic nanoparticles (MNPs), which are mainly attributed to the stabilizing agents. The smallest nanoparticles were obtained in the presence of trichloroacetate ions. The mechanism of formation of these suprastructures is strongly correlated with the end functional groups of the stabilizing agent. Thus, the obtained nanoparticles are potential candidates for contrast agents as well as targeted carrier for specific diseases, especially cancer. Ioana Lavinia Ardelean, Luric Bogdan Niculae Stoencea, Denisa Ficai, Anton Ficai, Roxana Trusca, Bogdan Stefan Vasile, Gheorghe Nechifor, and Ecaterina Andronescu Copyright © 2017 Ioana Lavinia Ardelean et al. All rights reserved. Grain Size Dependence of Elastic Moduli in Nanocrystalline Tungsten Wed, 07 Jun 2017 08:12:23 +0000 http://www.hindawi.com/journals/jnm/2017/3620910/ Using atomistic calculations with a Finnis-Sinclair type potential and molecular statics and dynamics methods, we performed a series of deformation tests on nanocrystallised tungsten samples presenting various microstructures; we calculated the elastic constants of polycrystalline tungsten for average grain diameters ranging from 2.7 to 6.7 nm. The results show that both Young’s and the shear moduli decrease by over 60% as the average grain diameter decreases below 3 nm. This diminution appears to be highly correlated to the grain boundary volume fraction. The results are compared to conclusions from other authors. P. Valat-Villain, J. Durinck, and P. O. Renault Copyright © 2017 P. Valat-Villain et al. All rights reserved. Gas Sensing Properties of NiSb2O6 Micro- and Nanoparticles in Propane and Carbon Monoxide Atmospheres Wed, 07 Jun 2017 00:00:00 +0000 http://www.hindawi.com/journals/jnm/2017/8792567/ Micro- and nanoparticles of NiSb2O6 were synthesized by the microwave-assisted colloidal method. Nickel nitrate, antimony chloride, ethylenediamine, and ethyl alcohol were used. The oxide was obtained at 600°C and was analyzed by X-ray diffraction (XRD) and Raman spectroscopy, showing a trirutile-type structure with cell parameters = 4.641 Å, = 9.223 Å, and a space group P42/mnm (136). Average crystal size was estimated at ~31.19 nm, according to the XRD-peaks. The microstructure was scrutinized by scanning electron microscopy (SEM), observing microrods measuring ~3.32 μm long and ~2.71 μm wide, and microspheres with an average diameter of ~8 μm; the size of the particles shaping the microspheres was measured in the range of ~0.22 to 1.8 μm. Transmission electron microscopy (TEM) revealed that nanoparticles were obtained with sizes in the range of 2 to 20 nm (~10.7 nm on average). Pellets made of oxide’s powders were tested in propane (C3H8) and carbon monoxide (CO) atmospheres at different concentrations and temperatures. The response of the material increased significantly as the temperature and the concentration of the test gases rose. These results show that NiSb2O6 may be a good candidate for gas sensing applications. Verónica-M. Rodríguez-Betancourtt, Héctor Guillén Bonilla, Martín Flores Martínez, Alex Guillén Bonilla, J. P. Moran Lazaro, José Trinidad Guillen Bonilla, M. A. González, and María de la Luz Olvera Amador Copyright © 2017 Verónica-M. Rodríguez-Betancourtt et al. All rights reserved. Silver Nanoparticles Obtained by Semicontinuous Chemical Reduction Using Carboxymethyl Cellulose as a Stabilizing Agent and Its Antibacterial Capacity Tue, 06 Jun 2017 08:05:48 +0000 http://www.hindawi.com/journals/jnm/2017/1390180/ Preparation of silver nanoparticles was carried out by semicontinuous reduction of Ag+ ions at low temperatures. Silver nitrate was used as the Ag0 precursor, the carboxymethyl cellulose (CMC) as stabilizer and primary reducing agent, and sodium borohydride as reducing agent. Weight ratios of 1 : 1 and 1 : 2 of AgNO3 : CMC were used for carrying out the reactions. Silver nanoparticles were characterized by UV-VIS spectroscopy, transmission electronic microscopy (TEM), and X-ray diffraction (XRD). The formation of silver nanoparticles was confirmed by XRD spectroscopy and by the presence of an absorption peak around 400 nm in the UV-visible spectrum. Unimodal size distributions of spheroidal nanoparticles were observed by TEM. Greater productivities than those reported by other authors were obtained with the advantage of using a lower temperature and minor reaction times. By using a higher CMC/AgNO3 weight ratio or a higher concentration of AgNO3, AgNPs with larger average size were produced. Antibacterial activity of AgNPs against S. aureus and E. coli was determined by the agar disk diffusion method. The higher the AgNPs concentration, the larger the inhibition zone. The minimum inhibitory concentration (MIC) of AgNPs against S. aureus and E. coli was 5 μg/disk. M. A. Pedroza-Toscano, S. López-Cuenca, M. Rabelero-Velasco, E. D. Moreno-Medrano, A. P. Mendizabal-Ruiz, and R. Salazar-Peña Copyright © 2017 M. A. Pedroza-Toscano et al. All rights reserved. Preparation and Characterization of Emamectin Benzoate Solid Nanodispersion Tue, 06 Jun 2017 00:00:00 +0000 http://www.hindawi.com/journals/jnm/2017/6560780/ The solid nanodispersion of 15% emamectin benzoate was prepared by the method of solidifying nanoemulsion. The mean particle size and polydispersity index of the solid nanodispersions were  nm and , respectively. The high zeta potential value of  mV and stable crystalline state of the nanoparticles suggested the excellent physical and chemical stabilities. The contact angle and retention compared with microemulsions and water dispersible granules on rice, cabbage, and cucumber leaves indicated its improved wettability and adhesion properties. The bioassay compared with microemulsions and water dispersible granules against diamondback moths and green peach aphids provided an evidence of its enhanced biological activity. This formulation composition could avoid organic solvents and obviously reduce surfactants. It is perspective in raising bioavailability and reducing residual pollution of pesticides and further improving agricultural production and environmental safety. Dongsheng Yang, Bo Cui, Chunxin Wang, Xiang Zhao, Zhanghua Zeng, Yan Wang, Changjiao Sun, Guoqiang Liu, and Haixin Cui Copyright © 2017 Dongsheng Yang et al. All rights reserved. Electrochemical Biosensors Based on Nanostructured Carbon Black: A Review Mon, 05 Jun 2017 07:45:56 +0000 http://www.hindawi.com/journals/jnm/2017/4571614/ Carbon black (CB) is a nanostructured material widely used in several industrial processes. This nanomaterial features a set of remarkable properties including high surface area, high thermal and electrical conductivity, and very low cost. Several studies have explored the applicability of CB in electrochemical fields. Recent data showed that modified electrodes based on CB present fast charge transfer and high electroactive surface area, comparable to carbon nanotubes and graphene. These characteristics make CB a promising candidate for the design of electrochemical sensors and biosensors. In this review, we highlight recent advances in the use of CB as a template for biosensing. As will be seen, we discuss the main biosensing strategies adopted for enzymatic catalysis for several target analytes, such as glucose, hydrogen peroxide, and environmental contaminants. Recent applications of CB on DNA-based biosensors are also described. Finally, future challenges and trends of CB use in bioanalytical chemistry are discussed. Tiago Almeida Silva, Fernando Cruz Moraes, Bruno Campos Janegitz, and Orlando Fatibello-Filho Copyright © 2017 Tiago Almeida Silva et al. All rights reserved. Design and Characterization of Endostatin-Loaded Nanoparticles for In Vitro Antiangiogenesis in Squamous Cell Carcinoma Sun, 04 Jun 2017 08:27:03 +0000 http://www.hindawi.com/journals/jnm/2017/2539065/ The aim of this study is to effectively enhance antitumor activities of endostatin by preparing polymeric nanocarriers. NMR and FT-IR spectra confirmed the successful grafting of the CHT-g-PEI and CHT-g-PEI-PEG-NH2 conjugates. SEM micrographs confirmed the shape of endostatin-loaded nanoparticles to be spherical while both TEM and zeta size results showed nanoparticle’s average size to be 100.6 nm having a positively charged surface with zeta potential of 7.95 mV. The concentrations of CHT and TPP as well as the changing pH conditions account for the increased swelling pattern of endostatin-loaded nanoparticles and influenced endostatin release in vitro. PEI increased the overall amine protonation while PEG aggravated endostatin encapsulation and release. Nanoparticles swell and release endostatin at acidic tumor pH of 6.8 compared to physiological pH of 7.4. The native CHT-g-PEI-PEG-NH2 conjugate showed high cytocompatibility above 80% cell viability across tested formulations. Endostatin-loaded nanoparticles showed a significant reduction in cell viability across tested formulations, with 5.32% cell death at 125 μg/mL and 13.36% at 250 μg/mL following 24 hours’ incubation period. Interestingly, more than a fourfold (61.68%) increment in cytotoxicity was observed at nanoparticle concentration of 1000 μg/mL. It was concluded that CHT-g-PEI-PEG-NH2 is an effective cargo for endostatin delivery with antiangiogenic effect in squamous cell carcinoma. Samson A. Adeyemi, Yahya E. Choonara, Pradeep Kumar, Lisa C. du Toit, and Viness Pillay Copyright © 2017 Samson A. Adeyemi et al. All rights reserved. Formation and Characterization of Copper Nanocube-Decorated Reduced Graphene Oxide Film Sun, 04 Jun 2017 06:58:24 +0000 http://www.hindawi.com/journals/jnm/2017/5702838/ In this study, we present a new approach for the formation and deposition of Cu nanocube-decorated reduced graphene oxide (rGO-CuNCs) nanosheet on indium tin oxide (ITO) electrode using very simple method. Cubic Cu nanocrystals have been successfully fabricated on rGO by a chemical reduction method at low temperature. The morphologies of the synthesized materials were characterized by ultraviolet-visible (UV-vis) spectroscopy, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and atomic force microscopy (AFM). The as-formed CuNCs were found to be homogeneously and uniformly decorated on rGO nanosheets. We demonstrated that the individual rGO sheets can be readily reduced and decorated with CuNCs under a mild condition using L-ascorbic acid (L-AA). Such novel ITO/rGO-CuNCs represent promising platform for future device fabrication and electrocatalytic applications. M. Z. H. Khan, M. A. Rahman, P. Yasmin, F. K. Tareq, N. Yuta, T. Komeda, and R. A. Jahan Copyright © 2017 M. Z. H. Khan et al. All rights reserved. Nanofeatured Titanium Surfaces for Dental Implantology: Biological Effects, Biocompatibility, and Safety Sun, 04 Jun 2017 00:00:00 +0000 http://www.hindawi.com/journals/jnm/2017/6092895/ Nanotechnology enables the control and modification of the chemical and topographical characteristics of materials of size less than 100 nm, down to 10 nm. The goal of this review is to discuss the role of titanium substrates as nanoscale surface modification tools for improving various aspects of implantology, including osseointegration and antibacterial properties. Techniques that can impart nanoscale topographical features to endosseous implants are described. Since the advent of nanotechnology, cellular specific functions, such as adhesion, proliferation, and differentiation, have been better understood. By applying these technologies, it is possible to direct cellular responses and improve osseointegration. Conversely, modulating surface features by nanotechnology could have the effect of decreased bacterial colonization. Ruggero Rodriguez y Baena, Silvana Rizzo, Luigi Manzo, and Saturnino Marco Lupi Copyright © 2017 Ruggero Rodriguez y Baena et al. All rights reserved. Formulation and Characterization of Hydroquinone Nanostructured Lipid Carriers by Homogenization Emulsification Method Thu, 01 Jun 2017 00:00:00 +0000 http://www.hindawi.com/journals/jnm/2017/3282693/ Nanostructured lipid carrier (NLC) was prepared by homogenization emulsification method and improved with modified surfactants. The properties of nanoparticles were investigated using the NLC system for hydroquinone (HQ) as a model drug and by increasing the light stability of hydroquinone. The optimized condition of NLC in stirring was 1200 rpm, the homogenized speed was 8000 rpm, solid oil to liquid oil ratio was 3 : 7, and lecithin to surfactant ratio was 3 : 1. The particle size was  nm and the encapsulation efficiency was %. The zeta-potential of HQ-NLC was better than −30 mV. In the thermogravimetric analysis (TGA) studies, adding of PLANTACARE 2000 UP for HQ-NLC has better heat resisting property than the HQ-NLC only. The addition of PLANTACARE 2000 UP to NLC shows better permeability (125.10%) than that of Blank. In the stability studies, the HQ-NLC after UVA/UVB irradiation has better inhibition rate (34.25%) than that of the Blank. In the present study, NLC system has successfully improved the light stability and the skin permeability of active compound. Therefore, the NLC might be a potential delivery vehicle for transdermal products in the future. Pey-Shiuan Wu, Chih-Hung Lin, Yi-Ching Kuo, and Chih-Chien Lin Copyright © 2017 Pey-Shiuan Wu et al. All rights reserved. Modification of Functional Properties of Whey Protein Isolate Nanocomposite Films and Coatings with Nanoclays Wed, 31 May 2017 11:30:08 +0000 http://www.hindawi.com/journals/jnm/2017/6039192/ Whey protein based films have received considerable attention to be used for environment friendly packaging applications. However, such biopolymers are prevented for use in commercial packaging due to their limited mechanical and barrier performance. The addition of nanofillers is a common method to overcome those drawbacks of biopolymers. Whey protein isolate (WPI) based nanocomposite cast films and coatings were produced using montmorillonite and vermiculite clay as nanofiller in different concentrations. Uniform distribution of filler within the polymeric matrix was confirmed by scanning electron microscopy. Mechanical properties such as tensile strength as well as Young’s modulus were increased after increasing the filler content, while elongation at break values decreased. All samples showed weak barrier potential against water vapor. Nanoclay incorporation, however, reduced water vapor transmission rates by approximately 50%. The oxygen barrier performance was improved for all nanocomposites. Results also indicated proportionality with the filler ratio according to applied models. The highest barrier improvement factors (BIF) were greater than five for the cast films and even greater than sixteen for the coatings. Developed WPI-based composites depicted nanoenhanced material properties representing a promising alternative to fossil-based packaging films. Kerstin Müller, Marius Jesdinszki, and Markus Schmid Copyright © 2017 Kerstin Müller et al. All rights reserved. Effect of Microstructural Changes during Annealing on Thermoelectromotive Force and Resistivity of Electrodeposited Ni85.8Fe10.6W1.4Cu2.2 Alloy Wed, 31 May 2017 11:14:18 +0000 http://www.hindawi.com/journals/jnm/2017/8230615/ Ni85.8Fe10.6W1.4Cu2.2 alloy powder containing nanocrystals of an FCC-structured solid solution of iron, tungsten, and copper in nickel embedded in an amorphous matrix was electrodeposited from an ammonia citrate solution. The alloy exhibits thermal stability in the temperature range between 25°C and 150°C. Over the range 150−360°C, the alloy undergoes intense structural relaxation which considerably increases the electron density of states and, hence, its electrical conductivity. Less intense structural relaxation takes place at temperatures between 360°C and 420°C. In the temperature range of 420°C to 460°C, relatively more intense changes in the electron density of states at the Fermi level occur, as induced by the structural relaxation resulting from the stabilization of larger less mobile tungsten atoms and copper atoms. The large decrease in electrical resistivity and the high increase in the electron density of states at the Fermi level in the temperature range 460−520°C are due to amorphous matrix crystallization and FCC-phase crystal grain growth. M. Spasojević, A. Maričić, Z. Vuković, S. Đukić, L. Ribić-Zelenović, and M. Spasojević Copyright © 2017 M. Spasojević et al. All rights reserved. Facile Hydrothermal Synthesis of SnO2 Nanospheres as Photocatalysts Wed, 31 May 2017 11:12:04 +0000 http://www.hindawi.com/journals/jnm/2017/6976203/ Large amounts of SnO2 nanospheres are successfully synthesized through a simple and effective hydrothermal method. The as-synthesized products consist of numerous small SnO2 nanocrystals with an average diameter of 40 nm. The as-prepared SnO2 nanospheres are further used as the photocatalysts for photodegrading several organic dyes (methylene blue, methyl orange, Congo red, and rhodamine B) under UV light irradiation. The photocatalytic results show that the as-synthesized SnO2 nanospheres possess high photocatalytic activities. Compared with the degradation rates of other dyes, that of methylene blue reaches 98.5% by 30 min irradiation. It reveals that the as-prepared product might be potential candidate in wastewater purification. Wenquan Hu and Xiaoguang Yuan Copyright © 2017 Wenquan Hu and Xiaoguang Yuan. All rights reserved.