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Nanophycology is recognized as one of the most important and widely used interdisciplinary sciences by creating a connection between nanotechnology on the one hand and phycology on the other hand. Algal nanoparticle biosynthesis is a starting point in studies and research related to nanophycology. Nanophycology consists of two parts, nano and phycology, and by taking advantage of the high potential of algae such as high biological safety, easy production, fast growth, and high stability in the phycology part of this science, which is also known as algology, algae nanoparticles synthesis and make this section related to nanotechnology. In this way, algae are known as factories of biological nanomaterials and cause the production of bio-stable nanotechnology and the removal of environmental pollutants released due to nanochemistry. Nanotechnology produced by algae in the science of nanophycology, due to algae's unique physical and chemical properties compared to other biological entities such as plants, fungi, and bacteria, is used in various fields including medicine, biorefining, purification Water, etc. In this review article, the most important goals of the science of nanophycology, including the biosynthesis of algal nanoparticles and the potential of these compounds in various fields of application, have been examined and discussed. [Display omitted] • Nanophycology is the science of integrating nanotechnology in algae-based research. • Biocompatibility of nanotechnology is the most important goal of nanophycology. • Nanophycology provides a suitable solution to control environmental pollutants. • The most important approach of nanophycology is the safe synthesis of nanoparticles based on algae. [ABSTRACT FROM AUTHOR]

With the advancement of nanochemistry, artificial nanozymes with high catalytic stability, low manufacturing and storage cost, and greater design flexibility over natural enzymes, have emerged as a next-generation nanomedicine. The catalytic activity and selectivity of nanozymes can be readily controlled and optimized by the rational chemical design of nanomaterials. This review summarizes the various chemical approaches to regulate the catalytic activity and selectivity of nanozymes for biomedical applications. We focus on the in-depth correlation between the physicochemical characteristics and catalytic activities of nanozymes from several aspects, including regulating chemical composition, controlling morphology, altering the size, surface modification and self-assembly. Furthermore, the chemically designed nanozymes for various biomedical applications such as biosensing, infectious disease therapy, cancer therapy, neurodegenerative disease therapy and injury therapy, are briefly summarized. Finally, the current challenges and future perspectives of nanozymes are discussed from a chemistry point of view. As a kind of nanomaterials that performs enzyme-like properties, nanozymes perform high catalytic stability, low manufacturing and storage cost, attracting the attention of researchers from various fields. Notably, chemically designed nanozymes with robust catalytic activity, tunable specificity and multi-functionalities are promising for biomedical applications. It's crucial to define the correlation between the physicochemical characteristics and catalytic activities of nanozymes. To help readers understand this rapidly expanding field, in this review, we summarize various chemical approaches that regulate the catalytic activity and selectivity of nanozymes together with the discussion of related mechanisms, followed by the introduction of diverse biomedical applications using these chemically well-designed nanozymes. Hopefully our review will bridge the chemical design and biomedical applications of nanozymes, supporting the extensive research on high-performance nanozymes. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Novel nanoscale drug delivery biomaterials are of great importance for the diagnosis and treatment of different cancers. We have developed a new pegylated squalene (SQ-PEG) derivative with self-assembly properties. Supramolecular assembly with a lipophilic photosensitizer pyropheophorbide-a (Ppa) by nanoprecipitation gave nanoconstructs SQ-PEG:Ppa with an average size of 200 nm in diameter and a drug loading of 18% (w/w). The composite material demonstrates nanoscale optical properties by tight packing of Ppa within Sq-PEG:Ppa resulting in 99.99% fluorescence self-quenching. The biocompatibility of the nanomaterial and cell phototoxicity under light irradiation were investigated on PC3 prostate tumor cells in vitro. SQ-PEG:Ppa showed excellent phototoxic effect at low light dose of 5.0 J/cm2 as a consequence of efficient cell internalization of Ppa by the nanodelivery system. The diagnostic potential of SQ-PEG:Ppa nanoconstructs to deliver Ppa to tumors in vivo was demonstrated in chick embryo model implanted with U87MG glioblastoma micro tumors. Graphical Abstract Pegylated squalene (SQ-PEG) derivative and a lipophilic photosensitizer pyropheophorbide-a (Ppa) form supramolecular structures by self-assembly. SQ-PEG:Ppa nanoconstructs with average size of 200 nm in diameter and a drug loading of 18% (w/w). Nanoscale optical properties of Sq-PEG:Ppa result in 99.99% fluorescence self-quenching. SQ-PEG:Ppa composites promote cell internalization of Ppa which leads to excellent phototoxic effect at low light doses. SQ-PEG:Ppa efficiently deliver Ppa to U87MG glioblastoma micro tumors implanted in chick embryos in vivo demonstrating their diagnostic potential for cancer fluorescence detection. Unlabelled Image [ABSTRACT FROM AUTHOR]

A novel method was proposed for generating nanoscale surface patterns on single-crystal diamond by carbon diffusion with a microstructured titanium mold under controlled temperature and pressure. The depth, geometry, and surface integrity of the fabricated patterns were investigated by laser micro-Raman spectroscopy and white-light interferometry, and the titanium molds were analyzed by energy dispersive X-ray spectroscopy. The results showed that at specific temperatures and pressures, three-dimensional patterns with a depth of tens of nanometers and sloped/curved walls could be generated on a diamond surface after a few minutes, without causing any surface graphitization. The intensity profile and penetration depth of carbon atoms into the titanium were experimentally measured. [ABSTRACT FROM AUTHOR]

This mini-review summarizes the use of operando spectroscopy to investigate the dynamic structure of heterogeneous catalysts under working conditions. Following the background to the development of operando spectroscopy, we briefly reviewed the latest highlight on this subject. Then, two challenging but attention-grabbing techniques, that is operando techniques under the harsh conditions and the integration of operando techniques in a unit cell, were introduced. Likely, operando techniques open up new vistas to explore reaction mechanisms and help us design the next generation industrial catalysts. Current Opinion in Chemical Engineering 2016, 12 :1–7 This review comes from a themed issue on Nanotechnology Edited by Hong Yang and Hua Chun Zeng For a complete overview see the Issue and the Editorial Available online 4th February 2016 http://dx.doi.org/10.1016/j.coche.2016.01.004 2211-3398/© 2016 Elsevier Ltd. All rights reserved. [ABSTRACT FROM AUTHOR]

In this study, the effects of concentrations 0, 100, 250, 500, 750 and 1000 mg kg −1 of nanoscale zero-valent iron (nZVI) on germination, seedlings growth, physiology and toxicity mechanisms were investigated. The results showed that nZVI had no effect on germination, but inhibited the rice seedlings growth in higher concentrations (>500 mg kg −1 nZVI). The highest suppression rate of the length of roots and shoots reached 46.9% and 57.5%, respectively. The 1000mg kg −1 nZVI caused the highest suppression rates for chlorophyll and carotenoids, at 91.6% and 85.2%, respectively. In addition, the activity of antioxidant enzymes was altered by the translocation of nanoparticles and changes in active iron content. Visible symptoms of iron deficiency were observed at higher concentrations, at which the active iron content decreased 61.02% in the shoots, but the active iron content not decreased in roots. Interestingly, the total and available amounts of iron in the soil were not less than those in the control. Therefore, the plants iron deficiency was not caused by (i) deficiency of available iron in the soil and (ii) restraint of the absorption that plant takes in the available iron, while induced by (ⅲ) the transport of active iron from the root to the shoot was blocked. The cortex tissues were seriously damaged by nZVI which was transported from soil to the root, these were proved by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). This current study shows that the mechanism of iron deficiency in rice seedling was due to transport of active iron from the root to the shoot blocked, which was caused by the uptake of nZVI. [ABSTRACT FROM AUTHOR]

Selective reduction of nitrate over nanoscale zero–valent iron (nFe 0 ) modified metals (Pd and Cu) was investigated. Parameters of modified metal loading, metallic ratio (Pd:Cu), and H 2 gas supplying were investigated on the influence of nitrate reduction. Metal (Cu, Pd) deposited onto nanoiron was proven to be effective in promoting the formation of nitrogen gas and, on the other hand, suppressing the NH 4 + formation. Hydrogen gas feeding appeared to have a synergistic effect on nitrate removal and on nitrogen gas selectivity in all types of catalytic reductants. A catalyst with a loading of 10% of (Pd–Cu)–nFe 0 with a ratio of Pd:Cu of 2:1, and H 2 feeding showed the highest selective to N 2 : NH 4 + formation (51:42), compared to the others ((Cu–Pd)–nFe 0 , Cu–nFe 0 , Pd–nFe 0 and nFe 0 ). The significant improvement in initiating the formation of N 2 , on the other hand suppressing the formation of NH 4 + , was referred to an indirect electron–transferring process of nFe 0 to Cu and to Pd, consequently. In addition, kinetic evaluations on each catalyst was evaluated and used to postulate the selective reduction of nitrate phenomena. [ABSTRACT FROM AUTHOR]

In this study, the catalytic debromination of 1,2,4,5-tetrabrominated benzene (1245TBB) was performed in a solution of NaOH in alcohol (V isopropanol :V methanol = 99:1) in the presence of a nanoscale catalyst Pd/C at a temperature of 50°C. The final degradation product of 1,2,4,5-tetrabrominated benzene is benzene. The debromination efficiency of 1245TBB and its degraded intermediate products (1,2,4-tribromobenzene, 1,2,-dibromobenzene, and bromobenzene) were highly dependent on the Pd/C loading and NaOH concentration. The catalyst life was evaluated, which showed that the deactivated catalyst could be reactivated about 30% after washing with 100 mmol L -1 NaOH solution in isopropanol. The possible 1245TBB debromination mechanism and pathways are also proposed and discussed in this study. [ABSTRACT FROM AUTHOR]

Nanoparticles hold great promise for delivering medical cargos to cancerous tissues to enhance contrast and sensitivity of imaging agents or to increase specificity and efficacy of therapeutics. A growing body of data suggests that nanoparticle shape, in combination with surface chemistry, affects their in vivo fates, with elongated filaments showing enhanced tumor targeting and tissue penetration, while promoting immune evasion. The synthesis of high aspect ratio filamentous materials at the nanoscale remains challenging using synthetic routes; therefore we turned toward nature’s materials, developing and studying the filamentous structures formed by the plant virus potato virus X (PVX). We recently demonstrated that PVX shows enhanced tumor homing in various preclinical models. Like other nanoparticle systems, the proteinaceous platform is cleared from circulation and tissues by the mononuclear phagocyte system (MPS). To increase bioavailability we set out to develop PEGylated stealth filaments and evaluate the effects of PEG chain length and conformation on pharmacokinetics, biodistribution, as well as potential immune and inflammatory responses. We demonstrate that PEGylation effectively reduces immune recognition while increasing pharmacokinetic profiles. Stealth filaments show reduced interaction with cells of the MPS; the protein:polymer hybrids are cleared from the body tissues within hours to days indicating biodegradability and biocompatibility. Tissue compatibility is indicated with no apparent inflammatory signaling in vivo . Tailoring PEG chain length and conformation (brush vs. mushroom) allows tuning of the pharmacokinetics, yielding long-circulating stealth filaments for applications in nanomedicine. [ABSTRACT FROM AUTHOR]

The aim of the paper is to give a feasibility study on the material deposition of Nanoscale textured morphology of titanium and titanium oxide layers on titanium and glass substrates. As a recent development in nanoscale deposition, Physical Vapor Deposition (PVD) based DC magnetron sputtering has been the choice for the deposition process. The nanoscale morphology and surface roughness of the samples have been characterized using Atomic Force Microscope (AFM). The surface roughnesses obtained from AFM have been compared using surface profiler. From the results we can say that the roughness values are dependent on the surface roughness of the substrate. The glass substrate was relatively smoother than the titanium plate and hence lower layer roughness was obtained. From AFM a unique nano-pattern of a boomerang shaped titanium oxide layer on glass substrate have been obtained. The boomerang shaped nano-scale pattern was found to be smaller when the layer was deposited at higher sputtering power. This indicated that the morphology of the deposited titanium oxide layer has been influenced by the sputtering power. [ABSTRACT FROM AUTHOR]

For evaluation of oxidative degradation of industrial azo dye Rosso Zetanyl B-NG (RZ B-NG), three clay supported nanoscale zero-valent iron materials were synthesized: bentonite, kaolin and native clay-supported nanoscale zero-valent iron (B-nZVI, K-nZVI and NC-nZVI). All clays used as a support material not only dispersed and stabilized nanoscale zero valent iron (nZVI) but also improved the adsorption and degradation of dye as they consequently improved heterogeneous Fenton oxidation. Under the optimal conditions, for the used nanomaterial concentrations of 112, 168 and 224 mg/L for B-nZVI, NC-nZVI and K-nZVI, the decolourization efficiencies achieved were 92.7, 92.1 and 91.6% and appropriate TOC removals were 57.8, 57.2 and 50.7% in the same order. The best catalytic performance was exhibited when B-nZVI was used. These results correlate with the specific surface area and mesoporous structure of the synthesized materials. They contributed to Fenton reaction enhancement by generating effective reaction sites for potential adsorption and subsequent oxidative degradation of the azo dye. Based on these results, all clay supported nanomaterials have proved to be superior heterogeneous Fenton-like catalysts for removing azo dyes from wastewater. [ABSTRACT FROM AUTHOR]

This paper describes the method of assessing the composition of the intermetallic compounds in nanoscale electrolytic deposits. The formula was developed for calculating the deflection potential in the case of selective electrooxidation electronegative component of the alloy composition. The processes of electro binary electrolytic precipitation in mercury-rhodium chloride electrolyte by anodic stripping voltammetry were studied. It was established that an electrolytic precipitate contains rhodium, mercury and rhodium IC with mercury composition Hg 5 Rh. [ABSTRACT FROM AUTHOR]

The anthology of nanodimensional objects (NDO) and genetically-modifited products (GMP) from their discovery, research of properties and application before the detection of threats of their harmful and toxic influence on plants, animal and microorganisms is considered. On the basis of the review of properties is shown, that the threats connected to manufacture and application NDO and GMP can be compared with the destructive influence of the weapon of a mass defeat, such as, for example, radiating, chemical or bacteriological. However the specificity of a toxic influence of NDO and GMP (as against the already known weapon of a mass defeat) can be strictly located on the certain object (or a number of objects). NDO and GMP can get in internal organs of living organism (or in microorganisms) mainly together with food, to destroy or to change their functional features. One of the unique features of such kind of a scientific discovery is that fact, that between the opening of such innovations, their mass production and the comprehension of them as threats of a mass defeat there passes rather large period of time -- lag reaches 10-th of years that essentially complicates in time to develop effectual measures of safety. [ABSTRACT FROM AUTHOR]

In globalized and highly technological XXI century it is not so obviously possible without using of nanochemistry and nanotechnology to ensure the safety of the society and the human being under terms of constantly growing level of complex threats. It is possible to claim that in the future the safety on a basis of nanosensors will be as "safety in everyone's pocket". In the present work the last achievements in the field of application of new nanosensors and development of new nanomaterials on a basis of nanodimensional objects (nanotubes, nanorods, nanowires) and spheroidal molecules (fullerenes and single-walled carbon nanotubes) for manufacturing of nanosensors are considered. [ABSTRACT FROM AUTHOR]

Summary: Progress in colloidal nanochemistry has been tremendous in the last decades. Nowadays a large variety of materials, sizes and shapes are accessible via colloid chemical methods. In the recent past research on colloidal nanocrystals has more and more focused on combining more than one functionality in one hybrid system. Fluorescent nanoparticles, magnetic nanoparticles and plasmonic nanoparticles are the three most common nanoparticles when looking at the particle functionality. Hence, in this review we summarize the most recent efforts undertaken in order to combine at least two of these properties in a hybrid system. Possible interactions in such hybrid systems are discussed together with possible synergetic effects giving rise to potential applications. [Copyright &y& Elsevier]

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Abstract: The ferroelectric phase transition for bulk and nanosized sodium nitrite was studied by the thermal noise method. It was shown that the intrinsic noise generated in the samples at frequencies above 10 MHz near the ferroelectric phase transition follows the behavior of the dielectric constant. The noise level in the loaded MCM-41 films with unidirectional pores was approximately twice as large as that for the pressed samples. [Copyright &y& Elsevier]

Abstract: Studying living bacteria at the nanoscale in their native liquid environment opens an unexplored landscape. We focus on Pseudomonas aeruginosa and demonstrate how the cell wall is biophysically affected at the nanoscale by two reference antibiotics (ticarcillin and tobramycin). The elasticity of the cells drops dramatically after treatment (from 263 ± 70 kPa to 50 ± 18 and 24 ± 4 kPa, respectively on ticarcillin- and tobramycin-treated bacteria) and major micro- and nano-morphological modifications are observed (the surface roughness of native, ticarcillin- and tobramycin-treated bacteria are respectively 2.5, 0.8, and 4.4 nm for a surface area of 40,000 nm²). Thus the nanoscale approach in liquid is valid and can be extended. From the Clinical Editor: Pseudomonas aeruginosa cell wall was demonstrated to be biophysically affected at the nanoscale by two reference antibiotics, ticarcillin, and tobramycin, with the elasticity dropping dramatically after treatment. [Copyright &y& Elsevier]

The effects of electron beam curing on the mechanical, thermal and electrochemical properties of inorganic nanoparticle based separators (IPSs) with various particle size distributions were investigated. We prepared IPSs consisting of 400 and 50 nm sized particles by varying the content of the 50 nm particles in the range from 0 to 100%. Al2O3 nanoparticles were successfully coated on a porous nonwoven matrix and then the effects of e-beam irradiation treatment as a function of the particle size were investigated. As the size of particles used for the separator was decreased, the mechanical and ionic conductivity of the IPS were greatly enhanced by the simple curing procedure using e-beam irradiation. The c-rate performance of the non-cured IPS prepared by blending the 400 and 50 nm sized Al2O3 was better than those of the IPSs based on the pure 400 and 50 nm particles. The c-rate performances were further improved by the e-beam treatment. [ABSTRACT FROM AUTHOR]

The acute toxicity of engineered nanoparticles (NPs) in aquatic environments at high concentrations has been well-established. This study demonstrates that, at a concentration generally considered to be safe in the environment, nano-TiO2 remarkably enhanced the toxicity of copper to Daphnia magna by increasing the copper bioaccumulation. Specifically, at 2mgL−1 nano-TiO2, the (LC50) of Cu2+ concentration observed to kill half the population, decreased from 111μgL−1 to 42μgL−1. Correspondingly, the level of metallothionein decreased from 135μgg−1 wet weight to 99μgg−1 wet weight at a Cu2+ level of 100μgL−1. The copper was found to be adsorbed onto the nano-TiO2, and ingested and accumulated in the animals, thereby causing toxic injury. The nano-TiO2 may compete for free copper ions with sulfhydryl groups, causing the inhibition of the detoxification by metallothioneins. [Copyright &y& Elsevier]

The article presents a study on the transport and retention of nanoparticles of fullerene in natural soils. It states that commercial production and use of fullerene nanomaterials will inevitably lead to their release into the environment. It highlights a series of one-dimensional column experiments to assess the transport and retention of nanoscale fullerene aggregates in water-saturated soils. The study suggests that the transport of fullerene aggregates in natural soils containing organic matter and clay minerals.

Summary: One frontier approach of colloidal chemistry to nanoscale entities capable to exhibit enhanced or even unconventional physical–chemical properties as well as diversified capabilities for multitask applications envisages fabrication of breed-new hybrid nanocrystals (HNCs) with a spatially controlled distribution of their chemical composition. These are all-inorganic multicomponent nanoheterostructures in which domains of distinct materials are arranged via permanent bonding interfaces in elaborate concentric/eccentric onion-like or oligomer-type architectures. This review covers recent progress achieved in the wet-chemical development of HNCs based on functional associations of semiconductors, metals and magnetic compounds. Within the frame of seeded-growth techniques to heteroepitaxial deposition in solution media, relevant synthetic strategies are illustrated, along with systematic examination of the mechanisms by which heterostructures can be selectively accessed in nonequivalent topological configurations. The peculiar properties and technological perspectives offered by such novel generations of complex nanomaterials are also succinctly highlighted. [ABSTRACT FROM AUTHOR]

Abstract: The next generation of researchers are not only attempting to grasp their discipline and research areas, but also need to be well-versed in technology powered techniques for research and its dissemination - a shift referred to as eResearch. The iVEC summer internship program provides an intense research training program to help undergraduate students transition into postgraduate programs and innovative industry positions. Interns are supervised by leading researchers in areas including radio astronomy, nanochemistry and molecular dynamics. More than a summer research project, the program aims to give a comprehensive indoctrination into core and emerging techniques for research. This paper describes the evolution of the internship program, the goals and methods used and a reflection on the results we are observing. [ABSTRACT FROM AUTHOR]

Dyeable fine polypropylene (PP) fibre has remained a problem for decades. In this paper, blends of PP with P(St-EGDMA)/P(St-MMA-BA-MA) [poly(styrene-ethylene glycol dimethacrylate)/poly(styrene-methyl methacrylate-butyl acrylate-methyl acrylate)] core shell particles, have been used for the preparation of dyeable fine PP fibres. Dyeing experiment showed that the incorporation of the designed core shell particles markedly enhanced the dyeability of fine PP fibres with three distinct disperse dyes and the shades of these dyed fine fibres were deep and bright. Mechanical tensile tests showed that the particles had slight effect on the mechanical properties of fine PP fibres. The designed core shell particles were relatively monodispersed with nanoscale, and were stable during the melt-spinning process. Spinning possibility of the blends and crystallinity and orientation of the dyeable fine PP fibres were also investigated. The possible reasons for the increased depth of shade were proposed. [ABSTRACT FROM AUTHOR]

Abstract: To investigate the roles of intercellular gap junctions and extracellular ATP diffusion in bone cell calcium signaling propagation in bone tissue, in vitro bone cell networks were constructed by using microcontact printing and self-assembled monolayer technologies. In the network, neighboring cells were interconnected through functional gap junctions. A single cell at the center of the network was mechanically stimulated by using an AFM nanoindenter. Intracellular calcium ([Ca2+]i) responses of the bone cell network were recorded and analyzed. In the untreated groups, calcium propagation from the stimulated cell to neighboring cells was observed in 40% of the tests. No significant difference was observed in this percentage when the intercellular gap junctions were blocked. This number, however, decreased to 10% in the extracellular ATP-pathway-blocked group. When both the gap junction and ATP pathways were blocked, intercellular calcium waves were abolished. When the intracellular calcium store in ER was depleted, the indented cell can generate calcium transients, but no [Ca2+]i signal can be propagated to the neighboring cells. No [Ca2+]i response was detected in the cell network when the extracellular calcium source was removed. These findings identified the biochemical pathways involved in the calcium signaling propagation in bone cell networks. [Copyright &y& Elsevier]

Abstract: Molecular dynamics simulations were carried out to investigate the adsorption mechanisms of tripeptide Arg-Gly-Asp (RGD) on the nanotopography and perfect rutile TiO2 (110) surfaces in aqueous solution. It is shown that the amino groups (NH2 and ) and carboxyl group (COO−) of RGD are the main groups bonding to hydrophilic TiO2 surface by electrostatic and van der Waals interactions. It is also demonstrated that RGD adsorbs much more rapidly and stably on the nanotopography surface than the perfect surface. On the hydrophilic TiO2 surface, the water molecules occupy the adsorption sites to form hydration layers, which have a significant influence on RGD adsorption. On the perfect surface, since the fivefold titanium atom is surrounded by surface bridging oxygen atoms above it and has a water molecule bonding to it, the amino group NH2 is the adsorption group. However, because the pit surface exposes more adsorption sites and has higher surface energy, RGD can adsorb rapidly on the surfaces by amino groups NH2 and , and the carboxyl group COO− may edge out the adsorbed water molecules and bond to the surface titanium atom. Moreover, the surface with higher surface energy has more adsorption energy of RGD. [Copyright &y& Elsevier]

A corrosion-resistant electrocatalyst support was prepared by overcoating high surface-area diamond powder (3-6 nm diameter, 250 m/g) with a thin layer of boron-doped ultrananocrystalline diamond (B-UNCD) by microwave plasma-assisted chemical vapor deposition. This core-shell approach produces electrically conducting (0.4-0.5 S/cm) and high surface-area (150-170 m2/g) diamond powder (B-UNCD-D). Accelerated degradation testing was performed by thermogravimetric analysis (TGA) to assess the oxidation resistance (i.e., corrosion resistance) of powder in the absence and presence of nanoscale Pt. The oxidation onset temperature for B-UNCD-D powder decreased with the Pt loading from 0 to 30 wt % (Pt/C). However, compared with the bare powder, the rate of carbon consumption was significantly greater for Pt-(XC-72) as compared to the platinized diamond powder. For example, the temperature of the maximum carbon consumption rate, Td, occurred at 426°C for Pt-(XC-72) (20% Pt/C), which was 295°C lower than the Td for bare XC-72. In contrast, Td for Pt-(B-UNCD-D, 20% Pt/C) was 558°C; a temperature that was only 62°C lower than that for bare diamond. Isothermal oxidation at 300°C for S h produced negligible weight loss for Pt-UNCD-D (20% Pt/C) while a 75% weight loss was observed for Pt-(XC-72) (20% Pt/C). The results clearly demonstrate that platinized diamond is more resistant to gas phase 6xidation than is platinized Vulcan at elevated temperatures. [ABSTRACT FROM AUTHOR]

Chemical mechanical polishing (CMP) can lead to nanoscale damage in films and surface features due to normal and lateral deformations of the surface. Defects arise due to the synergistic effects of chemical and mechanical mechanisms. This occurrence increases with severity as feature sizes are on the same order as abrasive polishing particles and materials decrease in stiffness, as with advanced low-k dielectrics. Here, relationships describing the response of normal and lateral surface deformations have been developed experimentally and from contact modeling. This is achieved by atomic force microscopy nanoscratching with diamond tips in a KOH environment to simulate CMP processing conditions. The deformations are related to the applied normal load, friction coefficient, film properties, and line densities. The deformations are observed to have critical loads of 1 and 5 μN associated with normal and lateral deformations, respectively, which are on the same order as actual CMP particle pressure estimates. [ABSTRACT FROM AUTHOR]

Results from process simulations of the stress memorization technique (SMT) for nanoscale n-channel metal-oxide-semiconductor field effect transistors (n MOSFETs) are presented. The spatial distribution of stress components within the device was computed for (i) different germanium doses in the preamorphization implant step, (ii) different peak anneal temperatures in spike annealing, and (iii) different tensile stresses of the capping layer. The effect of the dielectric spacer is considered. During the spike anneal, stress is enhanced in the dielectric spacer due to the viscoelastic relaxation of the capping layer. The stress induced in the channel by the spacer and polysilicon after capping layer etch is nonuniform with maxima near the edges of the gate. Supplementary micro-Raman measurements of SMT test structures and electrical measurements of fabricated SMT devices are consistent with the simulation results. [ABSTRACT FROM AUTHOR]

The electrochemical performances of nanoscale LiFePO4 and Li4Ti5O12 materials are described in this paper. The nanomaterials were synthesized by pyrolysis of an aerosol precursor. Both compositions required moderate heat-treatment to become electrochemically active. LiFePO4 nanoparticles were coated with a uniform, 2-4 nm thick carbon coating using an organic precursor in the heat-treatment step and showed a high tap density of 1.24 g/cm³ despite the 50-100 nm particle size and 2.9 wt % carbon content. Li4Ti5O12 nanoparticles were between 50 and 200 nm and showed a tap density of 0.8 g/cm³. The nanomaterials were tested both in half-cell configurations against Li metal and in LiFePO4/Li4Ti5O12 full cells. Nano-LiFePO4 showed a high discharge rate capability with values of 150 and 138 mAh/g at C/25 and 5C, respectively, after constant C/25 charges. Nano-Li4Ti5O12 also showed a high charge capability with values of 148 and 138 mAh/g at C/25 and 5C, respectively, after constant C/25 discharges; the discharge (lithiation) capability was comparatively slower. LiFePO4/Li4Ti5O12 full cells deliver charge/discharge capacity values of 150 and 122 mAh/g at C/5 and SC, respectively. [ABSTRACT FROM AUTHOR]

The article focuses on a study that describes the NANOLAB model for teaching nanoscale science and education (NSE) concepts across departmental boundaries, including how it was developed and some of its successes. It cites the features of NANOLAB, an upper-division undergraduate laboratory hub. It mentions the initial cost needed to develop the NANOLAB. It details the benefits of the NANOLAB to chemical engineering students.

Nanoscale patterns are created on silicon (100) surfaces via cathodic electrografting of alkyls. Self-assembled polystyrene microspheres on silicon surfaces can serve as dielectric masks. Cathodic potentials are applied to masked substrates in liquid hexynoic acid or phenylacetylene leading to the formation of nanoscale islands with monolayers of covalently bound functional groups on silicon. Silicon surfaces functionalized with islands of hexynoic acid are demonstrated using a biotin reaction. Cyclic voltammetry, scanning electron microscopy, and atomic force microscopy are used to characterize the patterned surfaces. The method provides a facile and high throughput process for spatially defining the local reactions on silicon with nanometer-scale resolution. [ABSTRACT FROM AUTHOR]

This paper presents a BSIM-based method for source/drain series resistance and mobility extraction in nanoscale strained-silicon metal oxide semiconductor field effect transistors (MOSFETs) with halo implants. This method is more accurate than the conventional channel-resistance and shift and ratio method because it considers the gate-length dependence of mobility caused by local uniaxial stress and laterally nonuniform channel doping. We have verified this method using samples with different stressor/ doping conditions and good agreement with experimental data has been obtained. The accuracy of the Berkeley Short-channel IGFET model (BSIM) Rsd extraction method is also proven by simulated current-voltage characteristics with different external resistant values. Significant mobility degradation in the short-channel regime has been observed for various uniaxial stressors. This method may serve as a suitable process monitor tool for ultrashallow junction and strained process development. [ABSTRACT FROM AUTHOR]

A comparative analysis of the influence of two different ferromagnetic nanoadditives on the rheological properties of polyacrylonitrile spinning solutions in DMF, as well as on the porous structure and tensile strength properties of nanocomposite fibres obtained from these solutions, was carried out. A ferromagnetic commercial product of the company Sigma-Aldrich and a product manufactured at the AGH University of Science and Technology, Krakow, Poland were used in this study. The influence of the amount of both types of nanoadditives inserted into the fibre matrix on their structure and tensile strength properties was determined. The uniformity of distribution of the nanoadditive on the fibre surface was estimated on the basis of SEM + EDS investigations. [ABSTRACT FROM AUTHOR]

Ce[sup3+]-doped nanocrystalline terbium aluminum garnet (Tb[sub3]Al[sub5]O[sub12]:Ce[sup3+], TAG:Ce[sup3+]) phosphors were successfully synthesized in low temperature by nitrate-citrate gel combustion method using microwave irradiation as a heating source. The pure TAG phase was obtained after calcining at 800°C for 6 h. The prepared nanocrystalline phosphors showed a broad peak at 551 nm, and the maximum doping concentration of Ce[sup3+] for the highest emission intensity was 0.8 mol % at 551 nm. The temperature dependence on photoluminescence properties of the prepared TAG:Ce[sup3+] phosphors was investigated from 25 to 275°C, and the activation energies (ΔE) for thermal quenching was determined by Arrhenius fitting. The experimental results clearly indicate that prepared nanocryatalline TAG:Ce[sup3+] has great potentials for a down-conversion yellow phosphor in white light emitting diodes. [ABSTRACT FROM AUTHOR]

We studied nanoscale interdigitated array electrodes (nano-IDAEs) to create a detector platform for highly sensitive biosensing devices. We successfully fabricated a gold nano-IDAE with 1000 pairs of electrodes (width and gap both 250 nm) and a 1 mm band length. We also fabricated a series of IDAEs whose widths and gaps ranged from 250 nm to 2 μm, and performed cyclic voltammetry with the IDAEs using 100 μm of ferrocenylmethyl trimethyl ammonium bromide solution to evaluate their characteristics. As the width and gap (line and space) of the IDAEs decreased, the difference between the experimental and theoretical limiting currents became larger, and when the line and space were 250 nm, the limiting currents were 20% higher than the theoretical value. We also employed the nano-IDAEs for measuring adrenaline. We demonstrated that the collection efficiency of 0% obtained when using a 2 μm IDAE could be improved to more than 60% when using a 250 nm IDAE. [ABSTRACT FROM AUTHOR]

Nanoscaled and nanoporous (La0.5Sr0.5)CoO3-δ (LSC) thin film cathodes (film thickness ranging from 200 to 300 nm, grain and pore size in the range of 50 nm) were electrochemically characterized to determine their potential for intermediate and low-temperature solid oxide fuel cells (SOFCs). Chemically homogeneous, large area (25 cm²), and nanoporous LSC thin films were derived from metallorganic precursors (metallorganic deposition) and deposited on yttria-doped zirconia [(YSZ) "design I"] and gadolinia-doped ceria [(GCO) "design 2"]. The area-specific polarization resistance (ASRpol) of both designs was evaluated on symmetrical cells with special emphasis on constancy, depending on temperature (500-850°C) and time by means of electrochemical impedance spectroscopy. For both designs, we report the capability of low polarization resistances, e.g., at 600°C, 146 mΩ cm² (LSC/YSZ), respectively, 130 mΩ cm² (LSC/OCO). Oxygen reduction reaction was facilitated by a substantial inner surface area of the porous thin-film cathode, as suggested by the application of Adler's model. Nanoporous LSC thin-film cathodes from this study were compared to alternative design concepts for high-performance porous cathodes and with dense (La0.52Sr0.48)(Co0.18Fe0.82)O3-δ thin-film cathodes. Furthermore, the aim of our study was (i) to find a temperature regime with a perspective for chemical durability of an LSC/YSZ interface. We could prove that at a temperature of 500°C and for 100 h, polarization resistance of the LSC/YSZ interface remains constant, and at unreported low values, which reopens LSC/YSZ for micro-SOFC application; (ii) to estimate the structural durability of nanoscaled and nanoporous LSC thin-film cathodes. We have been able to demonstrate stable and unreported low polarization resistance for LSC/GCO in the temperature range between 500 and 700°C, which is of technical interest for auxiliary-power-unit application. [ABSTRACT FROM AUTHOR]

The article focuses on discrete nanoscale transport (DNT) which refers to the movements and interactions of the nanoscale entities within a cell organelle. Nanoscale pertains to the nano-morphological features of the discrete entities that are transported and their relevant interactions. The transport is influenced by thermal motility and their interactions with cellular structures, molecular entities and other nanoscale. Furthermore, the basic nanoscale transport processes are discussed as well as the factors that disrupt DNT.

Classical theories of the strength of solids, such as fracture mechanics or those based on the maximum stress, assume a continuum. Even if such a continuum hypothesis can be shown to work at the nanoscale for elastic calculations, it has to be revised for computing the strength of nanostructures or nanostructured materials. Accordingly, quantized strength theories have recently been developed and validated by atomistic and quantum-mechanical calculations or nanotensile tests. As an example, the implications for the predicted strength, today erroneously formulated, of a carbon-nanotube-based space elevator megacable are discussed. In particular, the first ab initio statistical prediction for megacable strength is derived here. Our findings suggest that a megacable would have a strength lower than ≈45 GPa. [Copyright &y& Elsevier]

Extremely high aspect ratios, molecularly smooth hydrophobic graphitic walls, and nanoscale inner diameters of carbon nanotubes give rise to the unique phenomenon of ultra-efficient transport of water and gas through these ultra-narrow molecular pipes. Water and gas molecules move through nanotube pores orders of magnitude faster than through other pores of comparable size. The proposed water transport mechanism has a distinct similarity to the transport mechanisms of biological ion channels. Molecular dynamics simulations and experimental measurements of water transport underscore the importance of nanotube structure in enabling ultra-efficient transport through the pore. [Copyright &y& Elsevier]

Hydrothermal activation was used to modify the lithium-insertion properties of graphitized carbon nanotubes. The resulting solids showed a net improvement in their performance as anodes for advanced lithium-ion batteries. The mechanism of the electrochemical reaction with lithium of the modified carbon nanotubes was studied by X-ray diffraction and a combined use of two powerful resonance spectroscopies: solid-state nuclear magnetic resonance and electron paramagnetic resonance. Lithium was first intercalated in the activated multiwalled nanotubes between graphene layers, forming n-stages. Interlayer expansion and misfit between curved layers caused fracture and exfoliation of the nanotubes with an irreversible loss of staging phenomena. The resulting solids displayed an improved capacity retention on successive cycles. The line shape of electron paramagnetic resonance and Knight shifts in nuclear magnetic resonance reveal the electronic changes induced by lithium incorporation-removal in activated nanotubes. These results suppose a new strategy to improve the electrochemical performance of graphitized carbon nanotubes. [ABSTRACT FROM AUTHOR]

Abstract: In this study we show the influence of surface roughness on gecko adhesion on both the nano- and macroscales. We present experimental data for the force necessary to pull off single spatulae from hard rough substrates and also detail observations on living geckos clinging to various surfaces. Both experiments consistently show that the effective adhesion shows a minimum for a root mean square roughness ranging from 100 to 300nm. [Copyright &y& Elsevier]

In the context of the search for fundamental size effects regarding electrical conduction, we analyze the transition from semi-infinite or isolated to overlapped depletion layers in appreciably dense nanocrystalline SrTiO3 ceramics occurring if the grain size becomes smaller than ∼ 100 nm. At these small grain sizes, the bulk impedance signal that is seen clearly for microcrystalline samples disappears, leaving only one impedance response, which can be attributed to the space-charge zones. Space-charge potentials and Mott—Schottky lengths are calculated and shown to be consistent with the assumption of the mesoscopic condition. In accordance with the increased homogeneity of the mesoscopic situation in an 80 nm sample, and unlike for microcrystalline samples, the impedance response is characterized by almost an ideal capacitance that no longer originates from space-charge polarization. These conclusions are corroborated by detailed numerical calculations using linear irreversible thermodynamics. [ABSTRACT FROM AUTHOR]

Nanoparticles and nanoengineered materials are no longer the sole province of laboratory investigation. An increasing number of products based on nanotechnologies are now finding their way into the marketplace. The growing commercialization of products exploiting novel properties observed at the nanoscale is being accompanied by calls for regulation. [Copyright &y& Elsevier]

Nanotechnology is seen as a transformative technology, which has the potential to stimulate scientific innovation while greatly benefiting society. However, the enthusiasm with which the scientific and technical communities are embracing the technology is being tempered by concerns over possible downsides, including risks to human health. “Are these concerns valid?” is a question being asked by many, but frequently from differing perspectives. Given the increasingly complex interface between nanotechnology and society, relevant answers will be built on solid science and framed within a societal context. [Copyright &y& Elsevier]