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A method is presented for synthesizing core-shell nanoparticles with a magnetic core and a porous shell suitable for drug delivery and other medical applications. The core contains multiple $\gamma$-Fe$_2$O$_3$ nanoparticles ($\sim$15~nm) enclosed in a SiO$_2$ ($\sim$100-200~nm) matrix using either methyl (denoted TMOS-$\gamma$-Fe$_2$O$_3$) or ethyl (TEOS-$\gamma$-Fe$_2$O$_3$) template groups. Low-temperature M{\"o}ssbauer spectroscopy showed that the magnetic nanoparticles have the maghemite structure, $\gamma$-Fe$_2$O$_3$, with all the vacancies in the octahedral sites. Saturation magnetization measurements revealed that the density of $\gamma$-Fe$_2$O$_3$ was greater in the TMOS-$\gamma$-Fe$_2$O$_3$ nanoparticles than TEOS-$\gamma$-Fe$_2$O$_3$ nanoparticles, presumably because of the smaller methyl group. Magnetization measurements showed that the blocking temperature is around room temperature for the TMOS-$\gamma$-Fe$_2$O$_3$ and around 250~K for the TEOS-$\gamma$-Fe$_2$O$_3$. Three dimensional topography analysis shows clearly that the magnetic nanoparticles are not only at the surface but have penetrated deep in the silica to form the core-shell structure.

A systematic investigation of magnetic nanoparticles and the formation of a core-shell structure, consisting of multiple maghemite ( γ - Fe 2 O 3 ) nanoparticles as the core and silica as the shell, has been performed using various techniques. High-resolution transmission electron microscopy clearly shows isolated maghemite nanoparticles with an average diameter of 13 nm and the formation of a core-shell structure. Low temperature Mossbauer spectroscopy reveals the presence of pure maghemite nanoparticles with all vacancies at the B-sites. Isothermal magnetization and zero-field-cooled and field-cooled measurements are used for investigating the magnetic properties of the nanoparticles. The magnetization results are in good accordance with the contents of the magnetic core and the non-magnetic shell. The multiple-core γ - Fe 2 O 3 nanoparticles show similar behavior to isolated particles of the same size.

We present a coarse-grained MARTINI model for methylene blue (MB) and investigate the interactions of MB with dioleylphosphatidylcholine (DOPC) lipid bilayers by molecular dynamics simulations. Our results show that the charge state of MB and the oxidation degree of the DOPC bilayer play critical roles on membrane properties. Oxidation of the DOPC bilayer significantly increases permeability of water and MB molecules, irrespective of the charge state of MB. The most significant changes in membrane properties are obtained for peroxidized lipid bilayers in the presence of cationic MB, with ∼11% increase in the membrane area per lipid head group and ∼7 and 44% reduction in membrane thickness and lateral diffusivity, respectively.

Phase stability is one of the crucial requirements for any material that can be used at elevated temperature applications such as thermal barrier coating (TBC). The most traditional TBC material, partially stabilized zirconia, limits the operating temperature due to its phase transformation. Conversely, the low thermal conductivity of fully stabilized zirconia (YSZ) may enable effective reduction of the surface temperature on the coated component, while avoiding deleterious phase transitions, although still being subjected to sintering and grain growth. It has been reported that addition of rare-earths as dopants to YSZ can significantly increase resistance to grain growth at high temperature. Keeping this under consideration, this work investigates the role of rare-earths (lanthanum and gadolinium) in increasing thermal stability of YSZ microspheres, the building blocks for high temperature photonics for reflective TBC. The spheres were produced by ultrasonic spray pyrolysis, and the doping led to significant improvement of stability by significant inhibition of grain growth. While the individual dopants showed significant growth and sintering inhibition up to 900 °C, co-doping with 4mol% of each (Gd and La) led to coarsening resistance up to 1000 °C for 3 h, when particles retained reasonable spherical features with nano-metric crystallite sizes. This article is protected by copyright. All rights reserved.

Thin films and nanowires were deposited across the full range of Co-Ni solution compositions via templated electrodeposition in citrate baths. Spectroscopic analysis indicated a high degree of anomalous deposition across all alloy compositions, with no significant composition differences seen between films and nanowires. Electrochemical and microstructural analyses indicated notable differences between structures deposited in low- and high-Ni environments.

Modeling and Analysis Multi-objective optimization of transesterifi cation in biodiesel production catalyzed by immobilized lipase Mahmoud Karimi, Arak University, Iran and Stanford University, CA, USA Bryan Jenkins and Pieter Stroeve, University of California Davis, CA, USA Received December 15, 2015; revised July 24, 2016; and accepted July 25, 2016 View online September 14, 2016 at Wiley Online Library (wileyonlinelibrary.com); DOI: 10.1002/bbb.1706; Biofuels, Bioprod. Bioref. 10:804–818 (2016) Abstract: In order to comply with criteria of green energy concepts and sustainability, a multi-objective analysis was performed for the transesterification of waste cooking oil (WCO) using immobilized lipase. Response surface methodology and artificial neural networks, followed by multiple response optimiza- tion through a desirability function approach were applied to individually and simultaneously evaluate the fatty acid methyl esters (FAME) content and the exergy effi ciency. Reaction time and concentra- tions of methanol, immobilized lipase and water were considered as the design variables in maximiz- ing FAME content and exergy effi ciency. The maximum individual desirability of FAME content was predicted to be 95.7% corresponding to a methanol to WCO molar ratio of 6.7, catalyst concentration of 45%, water content of 9% and reaction time of 25 h. However, based on the simultaneously optimi- zation of both the FAME content and the exergy effi ciency, the maximum overall desirability was found at a methanol to WCO molar ratio of 6.7, catalyst concentration of 35%, water content of 12% and reaction time of 20 h to achieve FAME content of 88.6% and exergy effi ciency of 80.1%, respectively. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd Keywords: thermodynamic analysis; enzymatic transesterifi cation; lipase immobilization; optimization; biodiesel; exergy Introduction imited energy reserves and increasing environmental pressure on greenhouse gases (GHGs) from fossil fuels has caused biodiesel (fatty acid alkyl esters) to become a topic of interest in and target of energy policy in many countries. 1,2 Biodiesel has drawn attention in the last decade as a low toxicity, biodegradable, renewable source L of fuel with generally lower exhaust emissions and reduced lifecycle GHG implications for CO, CO 2 and SO x in com- parison with petroleum fuels. Th erefore biodiesel is mostly considered an environmentally friendly alternative liquid fuel and energy product. 1,3 Biodiesel is produced by esterification of fatty acids or transesterification of triglycerides with short chain alco- hols like methanol and ethanol. Methanol is mostly used Correspondence to: Mahmoud Karimi, Department of Biosystem Engineering, Arak University, Arak, Iran 38156 – 879 or 105 Keck Science, Department of Chemistry, Stanford University, Stanford, CA. 94305, USA. E-mail: mkarimi2@stanford.edu or m-karimi@araku.ac.ir © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd

In this study the structural and magnetization properties of a CoFe2O4-based ferrofluid was investigated using x-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive x-ray spectroscopy (EDS), Mossbauer spectroscopy, and magnetic Compton scattering (MCS) measurements. The XRD diagram indicates that the nanoparticles in the ferrofluid are inverse spinel and TEM graph shows that the ferrofluid consists of spherical nanoparticles with an average diameter of 18± 1 nm, in good agreement with the size, 19.4 nm, extracted from line broadening of the XRD peaks. According to EDS measurements the composition of the nanoparticles is CoFe2O4. Mossbauer spectroscopy shows that the cation distributions are (Co0.38Fe0.62)[Co0.62Fe1.38]O4. The MCS measurement, performed at 10 K, indicates that the magnetization of the nanoparticles is similar to magnetization of maghemite and magnetite. While the magnetization of the inverse spinels are in [111] direction, interestingly, the magnetization deduced from MCS is in [100] direction. The CoFe2O4-based ferrofluid is found to be stable at ambient conditions, which is important for applications.

© 2015 Elsevier Ltd. 5-(Chloromethyl)furfural (CMF) is rapidly being established as a renewable platform chemical of great promise. The effects of mass transfer, reaction temperature, Hansen solvent parameters, solvent fraction, and initial glucose concentrations on yields of CMF, 5-(hydroxymethyl)furfural (HMF), 2-(hydroxyacetyl)furan (HAF), levulinic acid (LA), and humic matter were investigated in a two-phase system of 6M HCl and an organic solvent. The ability of the solvent to extract HMF from the aqueous phase is found to be critical to achieving high CMF yields. Effective solvents must possess at least a small degree of Hansen hydrogen bonding capacity, and a high polarity is beneficial. Yields of CMF and HAF decrease with increasing glucose concentration but the yield of HMF is largely unaffected. The maximum productivity of CMF is achieved at a glucose loading of ca. 1.5M across all solvent fractions tested.

Millions of off-grid homes in remote areas around the world have access to pico-hydro (5 kW or less) resources that are undeveloped due to prohibitive installed costs ($/kW). The Turgo turbine, a hydroelectric impulse turbine generally suited for medium to high head applications, has gained renewed attention in research due to its potential applicability to such sites. Nevertheless, published literature about the Turgo turbine is limited and indicates that current theory and experimental knowledge do not adequately explain the effects of certain design parameters, such as nozzle diameter, jet inlet angle, number of blades, and blade speed on the turbine's efficiency. In this study, these parameters are used in a three-level (3 4 ) central composite response surface experiment. A low-cost Turgo turbine is built and tested from readily available materials and a second order regression model is developed to predict its efficiency as a function of each parameter above and their interactions. The effects of blade orientation angle and jet impact location on efficiency are also investigated and experimentally found to be of relatively little significance to the turbine. The purpose of this study is to establish empirical design guidelines that enable small hydroelectric manufacturers and individuals to design low-cost efficient Turgo Turbines that can be optimized to a specific pico-hydro site. The results are also expressed in dimensionless parameters to allow for potential scaling to larger systems and manufacturers.

A method is presented for synthesizing core–shell nanoparticles with a magnetic core and a porous shell suitable for drug delivery and other medical applications. The core contains multiple γ-Fe2O3 nanoparticles (∼15 nm) enclosed in a SiO2 (∼100–200 nm) matrix using either methyl (denoted TMOS-γ-Fe2O3) or ethyl (TEOS-γ-Fe2O3) template groups. Low-temperature Mössbauer spectroscopy showed that the magnetic nanoparticles have the maghemite structure, γ-Fe2O3, with all the vacancies in the octahedral sites. Saturation magnetization measurements revealed that the density of γ-Fe2O3 was greater in the TMOS-γ-Fe2O3 nanoparticles than TEOS-γ-Fe2O3 nanoparticles, presumably because of the smaller methyl group. Magnetization measurements showed that the blocking temperature is around room temperature for the TMOS-γ-Fe2O3 and around 250 K for the TEOS-γ-Fe2O3. Three dimensional topography analysis shows clearly that the magnetic nanoparticles are not only at the surface but have penetrated deep in the silica to form the core–shell structure.

Biological nanochannels control the movements of different ions through cell membranes depending on not only those channels' static inherent configurations, structures, inner surface's physicochemical properties but also their dynamic shape changes, which are required in various essential functions of life processes. Inspired by ion channels, many artificial nanochannel-based membranes for nanofluidics and biosensing applications have been developed to regulate ionic transport behaviors by using the functional molecular modifications at the inner surface of nanochannel to achieve a stimuli-responsive layer. Here, the concept of a dynamic nanochannel system is further developed, which is a new way to regulate ion transport in nanochannels by using the dynamic change in the curvature of channels to adjust ionic rectification in real time. The dynamic curvature nanochannel-based membrane displays the advanced features of the anomalous effect of voltage, concentration, and ionic size for applying simultaneous control over the curvature-tunable asymmetric and reversible ionic rectification switching properties. This dynamic approach can be used to build smart nanochannel-based systems, which have strong implications for flexible nanofluidics, ionic rectifiers, and power generators.

Core-shell nanoparticles comprised of Fe3O4 cores and a mesoporous silica shell with an average expanded pore size of 6.07 nm and coated with a poly(N-isopropylacrylamide) (PNIPAM) layer (CS MSNs EP PNIPAM) were prepared and characterized. The nanoparticles was loaded with (Ru(bipy)3 2+) dye or an antibacterial enzyme, lysozyme, to obtain CS MSNs EP PNIPAM Ru(bipy)3 2+ and CS MSNs EP PNIPAM Lys, respectively. The lysozyme loading was determined to be 160 mg/g of nanoparticle. It was seen that Ru(bipy)3 2+ and lysozyme release was minimal at a room temperature of 25 ºC while at physiological temperature (37 º C), abrupt release was observed. The applicability of the CS MSNs EP PNIPAM Lys was further tested with two Gram-positive bacteria samples, Bacillus cereus and Micrococcus luteus. At physiological temperature, the nanoparticles were shown to reduce bacterial growth, indicating a successful release of lysozyme from the nanoparticles. This nanoparticle system shows potential as a nanocarrier for the loading of similarly sized proteins or other species as a drug delivery platform., The authors wish to express their gratitude to the facilities at Ciudad Politecnica de la Innovacion (CPI), El Centro de Reconocimiento Molecular y Desarrollo Tecnologico (IDM), the Biotechnology Department at UPV, and the Instituto de Biologia Molecular y Celular de Plantas (IBMCP) at UPV for assistance in the materials characterization techniques and for providing the bacterial samples for antibacterial testing. Warm thanks are given to the Transatlantic Partnership for Excellence in Engineering (TEE) program, an Erasmus Mundus-Action 2 project by the European Commission, for the opportunity to undertake research at the collaborating university, UPV. The University of California Office of the President (UCOP) Lab Fees Research Program funded this research. The authors also thank the Spanish Government (Projects MAT2012-38429-C04-01 and MAT2012-38429-C04-03), the Generalitat Valenciana (Project PROMETEOII/2014/047) for support.

© 2015 The Authors. Published by Elsevier B.V. We use Molecular Dynamics and Monte Carlo simulations to examine molecular transport phenomena in nanochannels, explaining four orders of magnitude difference in wheat germ agglutinin (WGA) protein diffusion rates observed by fluorescence correlation spectroscopy (FCS) and by direct imaging of fluorescently-labeled proteins. We first use the ESPResSo Molecular Dynamics code to estimate the surface transport distance for neutral and charged proteins. We then employ a Monte Carlo model to calculate the paths of protein molecules on surfaces and in the bulk liquid transport medium. Our results show that the transport characteristics depend strongly on the degree of molecular surface coverage. Atomic force microscope characterization of surfaces exposed to WGA proteins for 1000 s show large protein aggregates consistent with the predicted coverage. These calculations and experiments provide useful insight into the details of molecular motion in confined geometries.

© The Royal Society of Chemistry.2015. Poly(3,4-ethylenedioxythiophene)-poly(styrenesulphonate) (PEDOT:PSS) is the most used organic hole injecting or hole transporting material. The hole carrying matrix PEDOT is highly doped by the acidic dopant PSS. When coated onto a substrate, PEDOT:PSS makes a highly uniform conductive layer and a thin (

Ethanol produced from renewable biomass, such as lignocellulosic feedstock, is one of the alternative energy resources that can be environmentally friendly. However, physical and chemical barriers caused by the close association of the main components of lignocellulosic biomass, as well as starch, hinder the hydrolysis of cellulose and hemicellulose in lignocellulose as well as amylase and amylopectin in starch to fermentable sugars. One of the main goals of pretreatment for enzymatic hydrolysis is to increase the enzyme accessibility for improving digestibility of cellulose and starch. Ultrasound irradiation applied to cellulosic materials and starch-based feedstock was found to enhance the efficiency of hydrolysis and subsequently increase the sugar yield. Prior research conducted on applying ultrasonic technology for cellulose and starch pretreatment has considered a variety of effects on physical and chemical characteristics, hydrolysis efficiency and ethanol yield. This paper reviews the application of ultrasound irradiation to cellulose and starch prior to and during hydrolysis in terms of sugar and ethanol yields. It also addresses characteristics such as accessibility, crystallinity, degree of polymerization, morphological structure, swelling power, particle size and viscosity as influenced by ultrasonic treatment.

© 2017, Copyright © Taylor & Francis Group, LLC. In this study, injectable PEG-based hydrogels containing Laponite particles with mechanical and structural properties close to the natural articular cartilage are introduced. The nanocomposites are fabricated by imide ring opening reactions utilizing synthesized copolymers containing PEG blocks and nanoclay through a two-step thermal poly-(amic acid) process. Butane diamine is used as nucleophilic reagent and hydrogels with interconnected pores with sizes in the range of 100–250 µm are prepared. Improved viscoelastic properties compared with the conventional PEG hydrogels are shown. Evaluation of cell viability utilizing human mesenchymal stem cells determines cytocompatibility of the nanocomposite hydrogels.

© 2016 Elsevier B.V. High yield synthesis of yttria-stabilized zirconia (YSZ) porous microspheres can enable application in advanced thermal barrier coatings, exploiting reflective properties originated from high temperature photonics. The complexity of typical wet-chemistry processes utilized in microspheres manufacturing limits yield and can hardly deliver stable porous structures. Here, ultrasonic spray pyrolysis was utilized to produce high quantities of porous YSZ. Droplets of an aqueous precursor solution were dragged with continuous air flow into a furnace kept at temperatures varying from 700 to 1200 °C. Spherical fully cubic zirconia particles were obtained in all processing conditions, and the sizes of the spheres decreased as a function of the processing temperature, ranging from 484 to 373 nm (average diameters), while their crystallite sizes had an inverse trend, ranging from 4.9 to 25.2 nm. This was attributed to higher temperatures activating coarsening of the spheres.

© 2016 Elsevier Ltd A new methodology for the systematic study of thermoelectric generator (TEG) design and economic analysis is presented, with the objective of assessing the performance and financial feasibility of small-scale TEG installations, for 4 leading candidate thermoelectric materials. Temperature of a steam trap pipe surface were measured at the University of California Davis Pilot Brewery, and device performance was modeled using the finite-element modeling software ANSYS. The model integrated temperature-dependent material properties from leading candidate thermoelectric materials and experimental time-variant temperature data. Calculated power outputs were utilized in a net present value (NPV) framework to assess the financial feasibility and economic implications of small scale TEG installations, as well as to address the aspects of TEG research, design and implementation which have potential for rapid and substantive improvement. This model, along with case study results, provides a powerful platform for analyzing the performance of real-world systems and can be used to predict where further technological development on TEG materials and devices would be most effective. It is found that a BiSbTe based TEG generated the highest power output at the measured temperatures and consequently resulted in the highest NPV at the end of 25 years. Sensitivity analysis of the NPV revealed a strong dependence on the heat-exchanger cost, highlighting the importance of efficient heat transfer design. The zT necessary for a 7-year payback period as a function of the capital cost and hot-side temperature was also calculated for a SiGe based TEG.

© 2016 Elsevier B.V. Novel pore-expanded mesoporous silica nanoparticles (MSNs) with pore sizes of approximately 11 nm were synthesized and modified with thermoresponsive, poly(n-isopropylacrylamide) (PNIPAM) gating groups on the nanoparticle exterior surface and in addition with poly(ethylene-glycol) (PEG) within the porous interior to minimize protein adsorption. PEG traditionally has been grafted to the nanoparticle exterior to minimize non-specific binding and interactions with the biological environment, but due to the templating mechanism of MSN synthesis, both the pore interior and nanoparticle surface can be separately modified. Here, an improved control release behavior of bovine hemoglobin (BHb) was observed after PEGylating the interior porous framework, compared to the release BHb from unmodified MSNs. This can be attributed to the reduced protein denaturation on PEGylated silica that was observed using circular dichroism spectroscopy.

Triblock copolymers comprised of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO, or trade name Pluronic) interact with lipid bilayers to increase their permeability. Here we demonstrate a novel application of Pluronic L61 and L64 as modification agents in tailoring the release rate of a molecular indicator species from 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) bilayer-coated superparamagnetic Fe3O4/mesoporous silica core-shell nanoparticles. We show there is a direct relationship between the Pluronics' concentration and the indicator molecule release, suggesting Pluronics may be useful for the controlled release of drugs from lipid bilayer-coated carriers.

Transport of toluene or 2-methylnaphthalene through nanoporous syndiotactic polystyrene (sPS) film. The δe-sPS was used as a film for transport measurement of toluene or 2-methynaphthalene in hexane. These solutes basically transport in the non-crystalline regions of the polystyrene. The δe-sPS crystal is characterized by the nanopore in the unit cell, which is enough space for toluene to transport, but 2-methylnaphthalene is too large to transport in the pore. This results in low flux of 2-methylnaphthalene in the δe-sPS film.

Millimeter sized arrays of uniformly-distributed nanopores (180-220 nm) were created in thin (200 nm) silicon nitride membranes using interferometric lithography. Molecular transport properties of the fabricated devices were investigated experimentally and compared with those of state-of-the-art polycarbonate track etched membranes. Two similarly-sized proteins, bovine serum albumin (BSA) and bovine hemoglobin (BHb), were used as permeates in the transport experiments. Up to 40 fold higher pore fluxes were achieved with unmodified silicon nitride membranes relative to thicker commercial nanoporous membranes. Similarly, in mixed protein experiments, ∼5.0 and 1.9 fold higher BSA and BHb selectivities were obtained with fabricated thin membranes at pH 4.7 and 7.0, respectively, relative to the commercial nanoporous membranes.

© 2016 American Chemical Society. Molecular dynamics (MD) and Monte Carlo (MC) simulations were applied together for the first time to reveal the porous structure transformation mechanisms of mesoporous silica MCM-41 subjected to temperatures up to 2885 K. Silica was experimentally characterized to inform the models and enable prediction of changes in gas adsorption/separation properties. MD simulations suggest that the pore closure process is activated by a collective diffusion of matrix atoms into the porous region, accompanied by bond reformation at the surface. Degradation is kinetically limited, such that complete pore closure is postponed at high heating rates. We experimentally observe decreased gas adsorption with increasing temperature in mesoporous silica heated at fixed rates, due to pore closure and structural degradation consistent with simulation predictions. Applying the Kissinger equation, we find a strong correlation between the simulated pore collapse temperatures and the experimental values which implies an activation energy of 416 ± 17 kJ/mol for pore closure. MC simulations give the adsorption and selectivity for thermally treated MCM-41, for N2, Ar, Kr, and Xe at room temperature within the 1-10 000 kPa pressure range. Relative to pristine MCM-41, we observe that increased surface roughness due to decreasing pore size amplifies the difference of the absolute adsorption amount differently for different adsorbate molecules. In particular, we find that adsorption of strongly interacting molecules can be enhanced in the low-pressure region while adsorption of weakly interacting molecules is inhibited. This then results in higher selectivity in binary mixture adsorption in mesoporous silica.

© 2016 Elsevier Ltd and Techna Group S.r.l. Zeolites are broadly useful catalysts and molecular sieve adsorbents for purification. In this work the thermal degradations of bare and platinum-loaded ZSM-5 was studied with the goal of understanding the behavior of nanoporous solids at extreme temperatures comparable to those present in nuclear fuels. Zeolites were heated in air and nitrogen at temperatures up to 1500 °C, and then characterized for thermal stability via X-ray diffraction (XRD) and for gas adsorption by the Brunauer-Emmett-Teller (BET) method. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) were also employed. These results indicate zeolites are stable when heat-treated up to 800 °C and degrade slowly at higher temperatures. However, significant surface area degradation begins at 1025–1150 °C with an activation energy of 400 kJ/mole. At 1500 °C, gas adsorption measurements and SEM images show complete collapse of the porous structure. Critically for nuclear fuel applications, however, the zeolites still adsorb helium in significant quantities.

Cobalt fluted nanowires, novel nanostructures with a diameter of 200 nm consisting of a solid nanowire base and a thin, nanotubular flute shape, were grown in track-etched polycarbonate membranes via templated electrodeposition. The structures were characterized electrochemically via cyclic voltammetry, chronoamperometry, and charge stripping, and structurally via scanning electron microscopy, transmission electron microscopy, and focused ion beam cross-sectioning. Electrochemical and structural analysis reveals details of their deposition kinetics, structure, and morphology, and indicate possible mechanisms for their formation and control. These unique structures provide inspiration for an array of possible applications in electronics, photonics, and other fields.

© 2016 Elsevier B.V. A variety of nanostructured materials are produced through template-based synthesis methods, including zero-dimensional, one-dimensional, and two-dimensional structures. These span different forms such as nanoparticles, nanowires, nanotubes, nanoflakes, and nanosheets. Many physical characteristics of these materials such as the shape and size can be finely controlled through template selection and as a result, their properties as well. Reviewed here are several examples of these nanomaterials, with emphasis specifically on the templates and synthesis routes used to produce the final nanostructures. In the first section, the templates have been discussed while in the second section, their corresponding synthesis methods have been briefly reviewed, and lastly in the third section, applications of the materials themselves are highlighted. Some examples of the templates frequently encountered are organic structure directing agents, surfactants, polymers, carbon frameworks, colloidal sol–gels, inorganic frameworks, and nanoporous membranes. Synthesis methods that adopt these templates include emulsion-based routes and template-filling approaches, such as self-assembly, electrodeposition, electroless deposition, vapor deposition, and other methods including layer-by-layer and lithography. Template-based synthesized nanomaterials are frequently encountered in select fields such as solar energy, thermoelectric materials, catalysis, biomedical applications, and magnetowetting of surfaces.

© 2016 Elsevier B.V. All rights reserved. As organic electronics improve, there is increased research interest on the longevity and stability of both the device and individual material components. Most of these studies focus on post deposition degradation and aging of the film. In this article, we examine the stability of polyelectrolyte dispersions before film coating. We observe substantial differences in the solution properties of the transparent conducting polymer, S-P3MEET, when comparing fresh versus aged dispersions and relate these solution differences to film properties. The aged dispersion contains large agglomerates and exhibits a typical shear-thinning rheological behavior, which results in non-uniformity of the spin-coated films. Near edge X-ray absorption fine structure measurements were used to differentiate the changes in bonding and oxidation states and show that aged S-P3MEET is more highly self-doped than fresh S-P3MEET. We also show that addition of acid, salt or heat to fresh S-P3MEET can accelerate the degradation/aging process but are subjected to different mechanisms. Conductivity measurements of S-P3MEET films illustrate that there is a tradeoff between increased work function and decreased conductivity upon perfluorinated ionomer (PFI) loading. The formation of nanostructure in solution is also correlated to film morphology variations obtained from atomic force microscopy. We expect that dispersion aging is a process that commonly exists in most solution-dispersed polyelectrolyte materials and that the methodologies presented in this paper might be beneficial to future degradation/stability studies.

© 2016 Elsevier B.V. All rights reserved. Solution-processed organic electronic devices often consist of layers of polar and non-polar polymers. In addition, either of these layers could be doped with small molecular dopants. It is extremely important for device stability to understand the diffusion behavior of these molecular dopants under the thermal stress and whether the dopants have preference for the polar or the non-polar polymer layers. In this work, a widely used molecular dopant 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ) was chosen to investigate dopant site preference upon thermal annealing between the polar thiophene poly(thiophene-3-[2-(2-methoxy-ethoxy)ethoxy]-2,5-diyl) (S-P3MEET) and non-polar thiophene poly(3-hexylthiophene) (P3HT). F4TCNQ is able to p-type dope both P3HT and S-P3MEET. Further doping studies of S-P3MEET using near edge X-ray absorption fine structure spectroscopy, conductivity measurements and atomic force microscopy show that the F4TCNQ additive competes for doping sites with the covalently attached dopants on the S-P3MEET. Calorimetry measurements reveal that the F4TCNQ interacts strongly with the side-chains of the S-P3MEET, increasing the melting temperature of the side-chains by 30 °C with 5 wt% dopant loading. Next, the thermal stability of doping in the polar/non-polar (S-P3MEET/P3HT) bilayer architectures was investigated. Steady-state absorbance and fluorescence results show that F4TCNQ binds much more strongly in S-P3MEET than P3HT and very little F4TCNQ is found in the P3HT layer after annealing. In combination with reflectometry measurements, we show that F4TCNQ remains in the SP3MEET layer with annealing to 210 °C even though the sublimation temperature for neat F4TCNQ is about 80 °C. In contrast, F4TCNQ slowly diffuses out of P3HT at room temperature. We attribute this difference in binding the F4TCNQ anion to the ability of the ethyl-oxy side-chains of the S-P3MEET to orient around the charged dopant molecule and thereby to stabilize its position. This study suggests that polar side-chains could be engineered to increase the thermal stability of molecular dopant position.

BackgroundPhenol is one of the most versatile and important organic compound. It is also a growing concern as water pollutants due to its high persistence and toxicity. Removal of Phenol from wastewaters was investigated using a novel nanoparticle adsorption and nanofiltration technique named as Nanoparticle Assisted Nano Filtration (NANF).MethodsThe nanoparticle used for NANF study were silver nanoparticles and synthesized to three distinct average particle sizes of 10nm, 40nm and 70nm. The effect of nanoparticle size, their concentrations and their tri and diparticle combinations upon phenol removal were studied.ResultsTotal surface areas (TSA) for various particle size and concentrations have been calculated and the highest was 4710 × 10(12)nm(2)for 10nm particles and 180ppm concentration while the lowest was for 2461 × 10(11) for 70nm and 60ppm concentrations. Tri and diparticle studies showed more phenol removal % than that of their individual particles, particularly for using small particles on large membranepore size and large particles at low concentrations. These results have also been confirmed with COD and toxicity removal studies.ConclusionsThe combination of nanoparticles adsorption and nanofiltration results in high phenol removal and mineralization, leading to theconclusion that NANF has very high potential for treating toxic chemical wastewaters.

Concentrating solar panels (CSP) improve the process of solar drying Roma tomatoes. This paper presents a performance comparison between two mixed-mode solar dryers. The dryers were identically constructed, however one of the dryers utilized mobile and easily adjustable flat concentrating solar panels to maximize incident solar energy on the dryer. Temperatures inside the dryer that utilized the concentrating solar panels were approx. 10 °C higher than those in the normal dryer during the majority of a sunny day testing period. This increase in temperature led to shorter Roma tomato drying times in the dryer with CSP. The concentrating solar panels showed a considerable increase in drying rate on sunny days, with a 27% decrease in total drying time as compared to the normal dryer to reach the target dimensionless moisture content of 0.2. A less significant increase in drying capacity was achieved when the dryer was tested in simulated cloudy conditions. The faster drying rate achieved in the dryer utilizing solar concentrators, under both sunny and simulated cloudy conditions, demonstrates the ability to dry produce to an acceptable moisture content in a reasonable time, with the objective of reducing postharvest loss and preventing spoilage.

Because of their unique properties which are strongly dependent on the physicochemical properties of metal nanomaterials, noble metal nanostructures, particularly silver, have attracted much attention in the fields of electronics, chemistry, physics, biology, and medicine. Regarding biology and medical applications, silver nanoparticles (NPs) are recognized as a promising candidate to fight against resistant pathogens because of their significant antimicrobial activities. However, there are two major ignored issues with these NPs. First, the effect of various types of bacteria on antibacterial efficacy of silver NPs is ignored; second, there is no information on the pattern and compositions of both soft- and hard-corona proteins at the surface of NPs, which can define cellular responses to the NPs. In this article, the bacterial effect on the antibacterial capability of silver NPs with various geometries (i.e., sphere, wire, cube, and triangle) was probed; in this case, three different types of bacteria including Escherichia coli (E. coli), Bacillus subtilis, and Staphylococcus aureus were employed. The results showed that the type of bacteria can have quite a significant role in the definition of antibacterial efficacy of NPs, which has significant implications in the high yield design of NPs for antibacterial applications and will require serious consideration in the future. In addition, both soft- and hard-corona proteins were analyzed, and the effects of protein coated NPs on normal cells were evaluated. According to the results, the composition and thickness of protein coronas were strongly dependent on the physicochemical properties of silver NPs. We have found that the composition and thickness of the protein corona can evolve quite significantly as one passes from particle concentrations and shapes appropriate to in vitro cell studies to those present in in vivo studies, which has important implications for in vitro-in vivo extrapolations and will require more consideration in the future.

The electrochemical behavior of the Co–Sb system on Au substrate during cyclic voltammetry and potentiostatic deposition was investigated. Electrochemical behavior of Co and Sb was studied and compared to the Co–Sb system. At a negative potential (−0.9 V vs. Ag/AgCl) the electrochemical behavior of this binary system was similar to that of individual Co and Sb combined. For more negative vertex potentials (e.g., −1.2 V vs. Ag/AgCl), results from cyclic voltammetry have shown the presence of a new compound different from Co and Sb which could only be detected at slow sweep rate. The deposition performed at constant potentials between −1.0 and −1.2 V have resulted in films that were made of CoSb3 and Sb as indicated by XRD. Surface film studied by SEM and EDS has shown morphological and compositional non-uniformities caused by hydrogen evolution.

Crystallographic texture is one of the most sensitive parameters for controlling the microstructure of electrodeposited layers. In this work, we study the crystallographic texture of electrodeposited nickel–silicon carbide coatings. The nickel coatings containing SiC nanoparticles and microparticles were electrodeposited from an additive-free sulfate bath containing nickel ions and SiC particles. The effect of current density on the codeposited Ni/SiC was studied. The coatings were analyzed with scanning electron microscopy and X-ray diffraction. Pole figure studies were done to characterize the evolved crystallographic texture. The X-ray scans followed by Rietveld analysis using the Rietquan program were used for the determination of texture, lattice parameter, and grain size of the matrix. The Ni/SiC nano-electrocomposites, prepared at 7 A/dm2, exhibited improved properties in comparison to pure nickel electrodeposits. The properties of the composite coatings are associated with structural modifications...

For the last decade, researchers have attempted to construct photovoltaic (PV) devices using a mixture of inorganic nanoparticles and conjugated polymers. The goal is to construct layers that use the best properties of each material e.g., flexibility from the polymer and high charge mobility from the nanoparticles or blue absorbance from the polymer complementing red absorbance from the nanoparticles. This critical review discusses the main obstacles to efficient hybrid organic/inorganic PV device design in terms of contributions to the external and internal quantum efficiencies. We discuss in particular the role that ligands on the nanoparticles play for mutual solubility and electronic processes at the nanoscale. After a decade of work to control the separation distance between unlike domains and the connectivity between like domains at the nanoscale, hybrid PV device layers are gaining in efficiency, but the goal of using the best properties of two mixed materials is still elusive.

© 2015 American Chemical Society. The diffusion of molecules through and between organic layers is a seriousstability concern in organic electronic devices. In this work, the temperature-dependent diffusion of molecular dopants through small molecule hole transport layers is observed. Specifically we investigate bilayerstacks of small molecules used for hole transport (MeO-TPD) and p-type dopants (F4TCNQ and C60F36) used in hole injection layers for organic light emitting diodes and hole collection electrodes for organic photovoltaics. With the use of absorbance spectroscopy, photoluminescence spectroscopy, neutron reflectometry, and near-edge X-ray absorption finestructure spectroscopy, we are able to obtain a comprehensive picture of the diffusion of fluorinated small molecules through MeO-TPD layers. F4TCNQ spontaneously diffuses into the MeO-TPD material even at room temperature, while C60F36, a much bulkier molecule, is shown to have a substantially higher morphologicalstability. Thisstudy highlights that the differences in size/geometry and thermal properties of small molecular dopants can have a significant impact on their diffusion in organic device architectures.

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Skutterudite compounds form a new class of potential candidates for thermoelectric applications. Cobalt triantimonide (CoSb3) shows good thermoelectric properties at medium and high temperatures. Doping this system with substitution elements, for either Co or Sb or both, may result in an increase of the thermoelectric figure of merit (ZT). This work focused on the electrochemical doping and characterization of films and nanowires of Co-Sb system in citrate solutions using gold-coated PCTE templates. The electrodeposition was performed on gold surface that was pre-treated electrochemically to ensure reproducible results. The electrochemical treatment acted as an annealing process for the surface, which resulted in an increase in Au(111) as demonstrated by XRD. Detailed electrochemical studies including deposition-stripping experiments was performed in order to develop a better understanding of the co-deposition kinetics and a better control over the composition of doped Co-Sb system. Scanning electron microscopy (SEM/EDS) helped study the morphology and the composition of the doped and undoped Co-Sb system. Co-deposition of Co-Sb showed that the amount of Co is higher in nanowires than in film or mushroom caps due to the slow Sb deposition rate dictated by slow Sb(III) complex diffusion. Doped nanowires have been also obtained. Both Ni and Te electrochemical doping of the Co-Sb system affected the composition of the deposit but there was no effect on nanowire morphology.

This work focuses on innovation in CSP technologies over the last decade. A multitude of advancements has been developed during this period, as the topic of concentrated solar power is becoming more mainstream. Improvements have been made in reflector and collector design and materials, heat absorption and transport, power production and thermal storage. Many applications that can be integrated with CSP regimes to conserve (and sometimes produce) electricity have been suggested and implemented, keeping in mind the environmental benefits granted by limited fossil fuel usage.

In biomass-to-fuel conversion, the biomass needs to be pretreated so that the cellulose in the plant fibers is exposed for conversion of the lignocellulosic biomass to fuels and chemicals. In this study, we report on the design and fabrication of a pulsed electric field (PEF) system for pretreatment of wood chip and switchgrass samples. Wood chip samples were given 1000 and 2000 pulses of 1 kV/cm, and 1000, 2000, and 5000 pulses of 10 kV/cm with a pulse width of 100 μs and frequency of 3 Hz. Switchgrass samples were given 1000, 2000, and 5000 pulses of 2.5, 5, 8, and 10 kV/cm with a pulse width of 100 μs and frequency of 3 Hz. The uptake of a colored dye neutral red C15H17ClN4 (MW ∼ 289) in untreated and PEF treated samples was studied to quantify the effect of PEF treatment on diffusion in plant tissues. Wood chip samples treated at 1 kV/cm showed a dye uptake similar to that of untreated wood chip samples. The switchgrass samples were resistant to change in the structure at low field strengths up to 5 k...

We report a magnetic technique for altering the apparent contact angle of aqueous droplets deposited on a nanostructured surface. Polymeric tubes with embedded superparamagnetic magnetite (Fe(3)O(4)) nanoparticles were prepared via layer-by-layer deposition in the 800 nm diameter pores of polycarbonate track-etched (PCTE) membranes. Etching away the original membrane yields a superparamagnetic film composed of mostly vertical tubes attached to a rigid substrate. We demonstrate that the apparent contact angle of pure water droplets deposited on the nanostructured film is highly sensitive to the ante situm strength of an applied magnetic field, decreasing linearly from 117 ± 1.3° at no applied field to 105 ± 0.4° at an applied field of approximately 500 G. Importantly, this decrease in contact angle did not require an inordinately strong magnetic field: a 15° decrease in contact angle was observed even with a standard alnico bar magnet. We interpret the observed contact angle behavior in terms of magnetically induced conformation changes in the film nanostructure, and we discuss the implications for reversibly switching substrates from hydrophilic to hydrophobic via externally tunable magnetic fields.

Solar energy can provide an abundant source of renewable energy (electrical and thermal). However, because of its unsteady nature, the storage of solar energy will become critical when a significan...