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Synthesis of nano‐particles using various greener approaches such as the use of plant extract, microbes, etc. is gaining a lot of popularity in the scientific community due to their advantages of being a cheaper protocol, reduction in the use of less hazardous chemicals, more environmentally benign method and good yield. It has been previously reported by many research groups that plant material provides reducing, capping as well as stabilizing agents and brings down biological and environmental risks in the green synthesis of nano‐particles. So it was thought worthwhile to synthesize copper oxide nano‐particles (CuO NPs) using some locally available medicinal plants. Rivina humilis L. plants which are available in our region of Vidarbha in Maharashtra State, India are considered to be the herbal plant for the treatment of respiratory‐related disorders mainly for asthma and cold by local tribal peoples. It has been found that it contains a variety of phytochemicals which can be employed for the synthesis of nanomaterials. With this aim it was thought worthwhile to present an efficient and greener approach for the synthesis of copper oxide nano‐particles using Rivina humilis L. (RH) whole plant extract. For characterization of bio‐synthesized CuO NPs, various spectral and analytical techniques such as UV‐Vis spectroscopy, FT‐IR, XRD, SEM, TEM, and EDS were employed. The newly synthesized CuO NPs were also tested for their potential biological activities against six different bacterial stains namely E. coli, P. aeruginosa, S. aureus, P. vulgaris, B. subtilis, and S. typhi using the well diffusion method. The antioxidant efficacy of the synthesized CuO NPs was undertaken through 1,1‐Diphenyl‐2‐picrylhydrazyl (DPPH) free radical scavenging activity. Their results have been presented and discussed in the present work. [ABSTRACT FROM AUTHOR]

Functional nanoparticles (NPs) have gained significant attention as promising applications in various fields, including sensor, smart coating, drug delivery, and more. Here, a novel mechanism assisted by machine‐learning workflow is proposed to accurately predict phase diagram of NPs, which elegantly achieves tunability of shapes and internal structures of NPs using self‐assembly of block‐copolymers (BCP). Unlike most of previous studies, onion‐like and mesoporous NPs in neutral environment and hamburger‐like NPs in selective environment are obtained. Such novel phenomena are obtained only by tailoring the topology of a miktoarm star BCP chain architecture without the need for any further treatment. Moreover, it is demonstrated that the BCP chain architecture can be used as a new strategy for tuning the lamellar asymmetry of NPs. It is shown that the asymmetry between A and B lamellae in striped ellipsoidal and onion‐like particles increases as the volume fraction of the A‐block increases, beyond the level reached by linear BCPs. In addition, an extended region of onion‐like structure is found in the phase diagram of A‐selective environment, as well as the emergence of an inverse onion‐like structure in the B‐selective one. The findings provide a valuable insight into the design and fabrication of nanoscale materials with customized properties, opening up new possibilities for advanced applications in sensing, materials science, and beyond. [ABSTRACT FROM AUTHOR]

Highlights Carbon nanotube (CNT) film is favored in structural health monitoring of advanced composite materials, primarily due to its commendable mechanical properties and piezoresistive properties. Nonetheless, floating catalytic chemical vapor deposition (FCCVD) is an attractive method for fabrication of CNT films, and the electrical response to strain of FCCVD‐prepared CNT films is impeded by high aspect ratio and lamellar packing structure. For this purpose, FCCVD CNT films were modified by HCl dissolving Fe impurities, nano‐SiO2 particles doping and freeze‐drying in combination to increase the spacing between CNTs and its networks as well as their strain sensitivities. It showed that the gauge factor (GF) according to the variation of resistance (ΔR/R0) of the co‐modified film (CNT‐HCl‐SiO2 film) was up to 15.6 for the tensile strain at the bottom surface of unidirectional carbon fiber reinforced plastic (CFRP) laminates during the process of bending tests. The bending cycle experiment of the CFRP showed relatively stable changes of ΔR/R0 with the strains for CNT‐HCl‐SiO2 film, while that of the pristine CNT film (CNT‐HCl‐0 film) displayed unstable non‐monotonic changes and that of HCl purified CNT film (CNT‐HCl‐10 film) revealed a gradual declining tendency. Moreover, the ΔR/R0 of CNT‐HCl‐SiO2 film exhibited excellent sensitivity to the strains of multiple bistable‐deformations of cross‐ply CFRP laminates. Strain gauge analysis indicated that a 51% increase of ΔR/R0 of CNT‐HCl‐SiO2 film at the 90° layer surface corresponded to the average strain of 434 με, meanwhile a 37% increase of ΔR/R0 of the CNT film at the 0° layer surface corresponded to the strain of averagely −173.9 με, and both exhibited super high GFs of 1175 and 2108, respectively. Based on this high sensitivity, CNT‐HCl‐SiO2 film also had the ability to predict the release of residual stress during the demoulding process of CFRP. Even SiO2 dispersion in CNT film, increased the pristine film thickness by 10 times GF of CNT‐HCl‐SiO2 film increased by 68% than CNT‐HCl‐0 film and by 164% than CNT‐HCl‐10 film SiO2 doping significantly improved the stability of the CNT film's ΔR/R0 with temperature and strain CNT‐HCl‐SiO2 film has the ability to monitor the deformation and residual stress of CFRP [ABSTRACT FROM AUTHOR]

Handling of agricultural residues is a major concern today, since they pose a serious threat to the environment. Pyrolysis is one among the different techniques explored across the globe towards the effective conversion of these crop residues into various useful products. In this work, the degradation behaviour of corn husk loaded with tin oxide nanoparticles and raw corn husk are characterized separately by employing thermogravimetric analyzer (TGA). From the thermograms obtained, the energy required for facilitating the degradation process with the aid of the catalyst is found to be 98.48 kJ/mol. Further, the corn husk loaded with prepared tin oxide nanoparticles (0.1 g& 0.2 g) is subjected to pyrolytic degradation at different temperature ranges from 400 °C to 550 °C and compared with thermal pyrolysis. The biochar retained from the pyrolysis process is investigated for its efficacy as an energy storage material after coating them over graphite sheet. Electrochemical analysis reveals the fabricated SnO2/biochar nanocomposite have excellent energy storage characteristics (205 F/g at a scan rate of 10 mV/s) which was attributed to the presence of facile architecture with porous surface area. The outcomes of the present study open fresh gateways for the innovative electrodes in energy domain. [ABSTRACT FROM AUTHOR]

Epoxy film adhesives are typically used in different industries. However, these adhesives suffer from brittleness, low flexibility, and thermal stability problems. In this research, phenolic resin (Novolac) and poly (butyl acrylate‐block‐styrene) were used in the formulation of epoxy film adhesive (Diglycidyl ether bisphenol A) to increase thermal stability and adhesion strength and as the toughening agent, respectively. Alumina nanoparticles were also employed to enhance the mechanical properties. The influence of block copolymer and alumina nano particles was also assessed on the mechanical and thermal properties of epoxy‐based film adhesives. The investigation of the mechanical properties of dumbbell‐shaped samples and adhesion strength of the Al‐Al bonded joints were evaluated by tensile, lap shear, and T‐peel tests. The thermal stability of the optimal samples was assessed by thermogravimetry analysis (TGA). SEM analysis was also utilized to study the toughening mechanism. Tensile test of the dumbbell‐shaped samples indicated that the incorporation of 2.5 phr block copolymer and 2 phr alumina nanoparticles enhanced the toughness to 250%. The shear and peel strengths of this sample also exhibited 51% and 76% increase, respectively, showing a remarkable synergistic effect. On the other hand, TGA results revealed that the incorporation of block copolymer improved the thermal stability of the adhesive matrix. The copresence of these two materials also showed a considerable synergistic effect on the thermal stability. The SEM results were also in line with the results of mechanical tests as the crack deviation, crack pinning, and debonding were the most important mechanisms of toughening. Highlights: A new platform was developed for designing epoxy films adhesives with high mechanical, adhesion, and thermal properties.The hybrid of butyl acrylate block styrene copolymer, phenolic resin, and alumina nanoparticles showed synergistic effects on the lap shear and T‐peel strength.The greatest improvement in toughness was related to the epoxy adhesive containing 2.5 phr block copolymer and 2 phr alumina nanoparticles.Analysis of the fracture surface showed that by using hybrid of nanoparticles and block copolymers in the epoxy film adhesive formulation, the cohesive failure occurred.The use of hybrid additives in film adhesive formulations enlightened manufacture of adhesives for future studies on adhesive formulations. [ABSTRACT FROM AUTHOR]

Highlights Due to its exceptional mechanical and crashworthiness properties, lightweight nanocomposites have recently been used more and more in aviation, defense, nautical, and automotive applications. Nanocomposite cylinders could be effectively employed in this respect as energy‐absorbing components for decreasing the impact energy during vehicle crashes. The current work examined the crashworthiness response of nano‐alumina (Al2O3) filled glass fiber reinforced epoxy (GFRE) composite tubes using quasi‐static lateral compressive loads. Crushing profiles and crush force–deformation curves of all representative samples were recorded and discussed. The total absorbed energy (AE) and specific absorbed energy (SEA) for tested specimens were assessed. Furthermore, a multi‐attribute decision making (MADM) technique known as complex proportional assessment (COPRAS) was used to compute the optimum nano‐Al2O3 wt%. Based on the experimental results, the addition of 1, 2, and 3 wt% of nano‐Al2O3 enhanced AE by 7.69%, 18.14%, and 51.21% and SEA by 3.43%, 13.98%, and 39.84%, respectively. While deteriorations of 6.59% and 17.41% in AE and SEA, respectively, were recorded with the addition of 4 wt% of nano‐Al2O3. Overall findings showed that (GFRE) composite tubes with 3 wt% of nano‐Al2O3 have a special potential to absorb energy. The designed tubes, that is, GFRE tubes filled with 0, 1, 2, 3, and 4 wt% of nano‐alumina (Al2O3) were created using wet‐wrapping by hand lay‐up technique. The fabricated tubes were subjected to lateral compression loads to investigate their crashworthiness behavior. The crashing load and absorbed energy versus displacement responses for the laterally loaded tubes were exposed. The histories of deformation were also examined. Complex proportional assessment (COPRAS) was used to find the optimum nano‐Al2O3 wt%. [ABSTRACT FROM AUTHOR]

Carbon‐phenolic ablators are very efficient heat shields for atmospheric reentry vehicles: they are able to protect a capsule from hyper thermal environments characterized by intense heat fluxes (>1 MW/m2) and very high temperature (also exceeding 300°C). Ablative materials can be modified by the addition of nano‐fillers in order to improve their performance: small amounts of nano‐fillers (in the order of 2–5 wt%) are able to enhance the matrix material properties, guarantying a weight saving too. In this work, three different kinds of ceramic nano‐particles (ZrO2, SiC, and MgO) were tested as fillers for a phenolic resin and for a carbon‐phenolic ablator: the variation in the mechanical properties and ablative performances were verified through mechanical tests and oxyacetylene flame exposure. The influence of the nano‐particles in the composite materials properties and the phenomena connected to their presence in the ablative material were deeply investigated with scanning electron microscope, EDS, XRD, and FTIR analysis. [ABSTRACT FROM AUTHOR]

BACKGROUND Pine oil contains a high percentage of polyunsaturated fatty acids, which make it prone to oxidation. Luteolin (LUT) micro‐nano particles with antioxidant properties can be used as stabilizers to form an edible oil‐in‐water Pickering emulsion to improve the oxidative stability of pine nut oil. RESULTS: Under optimal preparation conditions, the LUT micro‐nano particles and pine nut oil account for about 0.44 and 90.9 g·kg−1 of the total mass of the emulsion, respectively. The LUT particles in the suspension have a mean particle size of about 479 nm, present a sheet‐like structure with a cut surface of 30–50 nm, and can reduce the surface tension of deionized water. In the optimized Pickering emulsion, the emulsion droplets are approximately spherical and have a mean diameter of about 125.6 nm and uniform distribution. The optimized Pickering emulsion droplets can remain stable for up to 2 h in an environment where the pH levels are 7–8.5, ultraviolet B radiation (UVB) irradiation, of less than 5.0 g·kg−1, and at a temperature of 80 °C. The stability of the emulsion in simulated digestive fluid changed minimally. In the first 7 days of the accelerated oxidation experiment, LUT micro‐nano particles not only successfully protected the integrity of emulsion droplets but also fully inhibited the peroxidation of pine oil. CONCLUSION: The strong antioxidant properties of LUT micro‐nano particles, and the dense protective layer they formed, stabilized the Pickering emulsion successfully. The particles also improved the oxidation stability of pine nut oil. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Chemical bath method is adopted for growth of lead sulfide nano particles in methanolic solution of Pb(No3)2. Sulfur exchange is achieved by the controlled reaction of Na2S. The optical absorption studies have been done for obtained colloidal solution. The prepared particles are characterized by UV/Visible absorption spectra in the range 700–250 nm and the corresponding energy band gaps have been calculated assuming the effective masses of the electrons and holes in the nano particles to be same as that of bulk. The particle size has been determined by using the Wang Mahler and Brus L.E. Theoretical approaches. It is found that without using any capping agent the band gap of the compound gradually increases as the size of the particle decreases. [ABSTRACT FROM AUTHOR]

Uniformly distributed rectangular nanoparticles with some triangular particles of gadolinium selenide (Gd0.75Se) are prepared by the chemical precipitation method. It crystallizes in a cubic structure. It shows paramagnetic behavior along with interesting weak ferromagnetism at room temperature. In the present study, the cyclic voltammogram of electrolyte of Gd0.75Se shows pseudocapacitive behavior with a wider potential window of 3.75 V. The wider potential window electrolyte enhances applications in the super capacitor field for energy storage. The specific capacitance is 21 F g−1, and the energy density is 146 Wh kg−1. The observed high power density is 4.2 kW kg−1. The energy gap is 1.55 eV. A study of photoluminescence confirms the presence of native point defects. [ABSTRACT FROM AUTHOR]

The aim and objective of this review is to intensively summarize composite film materials that can achieve thermal radiation insulation without affecting visible light transmittance, in order to reduce the heat loss in greenhouses and thus save energy. Eight kinds of composite films, which could be used for radiation insulation, were finally determined and intensively reviewed by searching the key words including insulation film, insulation agent, and infrared insulation. These materials can be divided into two categories: silica/poly and zinc oxide/poly composites. The radiation thermal insulation property and light transmission property of these materials were experimentally tested by spectrometry. The key finding of this article includes that phonon resonance and Anderson localization could be used to block thermal infrared radiation by generalizing material properties. The conclusion of this review is that those materials have at least a 10% increase in infrared thermal radiation blocking, but only a small decrease in visible light transmittance. [ABSTRACT FROM AUTHOR]

Summary: The purpose of this study was to expound on the correlation between foaming properties and physicochemical characteristics of rice bran protein (RBP) samples. RBP nano‐particles (RBPNs) were prepared by acidic–thermal treatment under different RBP solution concentrations and treated times at 90 °C, and then the foaming properties were measured at pH 7.0 and pH 2.0. Compared to RBP, the foaming properties of RBPNs were increased at pH 7.0, and RBPNs could have better foam capacity but have no obvious changes in foam stability at pH 2.0. The results of Pearson correlation showed that the foaming properties were closely correlated with ζ potential, contact angle, and surface hydrophobicity for RBP and RBPNs, and a strong correlation between foaming capacity and surface hydrophobicity was shown for RBPNs. Additionally, the result of TEM images confirmed that RBPNs were inclined to form associated aggregates which may affect the physicochemical characteristics of RBPNs. [ABSTRACT FROM AUTHOR]

Nano‐SiO2 (NS), due to its prominent nucleation and pozzolanic effects, holds the promise to effectively enhance the tensile and compressive properties of high‐strength strain‐hardening cementitious composite (HS‐SHCC) at both early age (1d, 3d) and normal curing age (28d). The influence of nano‐SiO2 (NS) on the hydration, microstructure and mechanical properties of HS‐SHCC with different dosages (i.e., 0%, 1%, 2%, and 3% by mass of cement) were explored in this research. The nucleation effect of NS particles accelerated the hydration process, and the pozzolanic reaction tended to improve the hydration degree of matrix at the micro‐scale. The addition of NS particles decreased the porosity and refined the pore structure of the matrix. Single‐fiber pullout tests (meso‐scale) showed a remarkable improvement of interfacial bond stress with the incorporation of NS particles and consequently on the macro‐scale mechanical strengths enhancement of HS‐SHCC. The linkage between meso‐ and macro‐scale properties was established based on the micro‐mechanical model. The combination of filler effect, acceleration effect and pozzolanic reaction of NS particles enhanced the microstructures and mechanical properties of HS‐SHCC. The increase in compressive and tensile strength of NS‐modified HS‐SHCC could reach to 45% (1d) and 30% (1d), respectively, compared to those values of the reference specimen without NS addition. This research provided an effective way to enhance the tensile performance of HS‐SHCC, especially for the early‐age tensile property. [ABSTRACT FROM AUTHOR]

The aim of this work was to analyze the effects of long‐term exposure to titanium dioxide (TiO2) micro‐ (MPs) and nanoparticles (NPs) (six and 12 months) on the biochemical and histopathological response of target organs using a murine model. Male Wistar rats were intraperitoneally injected with a suspension of TiO2 NPs (5 nm; TiO2‐NP5 group) or MPs (45 μm; TiO2‐NP5 group); the control group was injected with saline solution. Six and 12 months post‐injection, titanium (Ti) concentration in plasma and target organs was determined spectrometrically (ICP‐MS). Blood smears and organ tissue samples were evaluated by light microscopy. Liver and kidney function was evaluated using serum biochemical parameters. Oxidative metabolism was assessed 6 months post‐injection (determination of superoxide anion by nitroblue tetrazolium (NBT) test, superoxide dismutase (SOD) and catalase (CAT), lipid peroxidation, and paraoxonase 1). Titanium (Ti) concentration in target organs and plasma was significantly higher in the TiO2‐exposed groups than in the control group. Histological evaluation showed the presence of titanium‐based particles in the target organs, which displayed no structural alterations, and in blood monocytes. Oxidative metabolism analysis showed that TiO2 NPs were more reactive over time than MPs (p <.05) and mobilization of antioxidant enzymes and membrane damage varied among the studied organs. Clearance of TiO2 micro and nanoparticles differed among the target organs, and lung clearance was more rapid than clearance from the lungs and kidneys (p <.05). Conversely, Ti concentration in plasma increased with time (p <.05). In conclusion, neither serum biochemical parameters nor oxidative metabolism markers appear to be useful as biomarkers of tissue damage in response to TiO2 micro‐ and nanoparticle deposits at chronic time points. [ABSTRACT FROM AUTHOR]

ABSTRACT: Chitosan (CS) and polyurethane‐chitosan (PU‐CS) nano‐particles (NPs) were prepared for the core formation by complex coacervation method whereas alginate (ALG) and PU‐ALG were crosslinked by ionic gelation method to form the protective shell‐layer over the core. Effects of PU incorporation either within the core or shell or both were investigated by different in vitro and in vivo parameters. Fourier transform infrared (FTIR) spectroscopy of different compositions of nano‐particles showed distinct characteristic peaks for CS, PU, and ALG, indicating their presence in variable ratios. Significance of polyurethane‐incorporated systems towards insulin encapsulation efficiency, swelling parameters, insulin release, and in vivo pharmacological effect were also studied. Particle sizes, zeta potential, morphological analysis, mucoadhesion study, and in vivo acute toxicity studies of these core–shell nano‐particles were also performed. Bioavailability of insulin ranged from 9.04% to 11.6% for polyurethane‐incorporated chitosan‐alginate core–shell nano‐particle formulations which was significantly higher than the insulin bioavailability of basic CS/ALG core–shell nano‐particle system. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46365. [ABSTRACT FROM AUTHOR]

The behavior of catalytic particles depends on their chemical structure and morphology. To reveal this information, the characterization with atom probe tomography has huge potential. Despite progresses and papers proposing various approaches towards the incorporation of particles inside atom probe tips, no single approach has been broadly applicable to date. In this paper, we introduce a workflow that allowed us to prepare atom probe specimens from Ga particles in suspension in the size range of 50 nm up to 2 μm. By combining dielectrophoresis and electrodeposition in a suitable way, we achieve a near‐tip shape geometry, without a time‐consuming FIB lift‐out. This workflow is a simple and quick method to prepare atom probe tips and allows for a high preparation throughput. Also, not using a lift‐out allowed us to use a cryo‐stage, avoiding melting of the Ga particles, while ensuring a mechanical stable atom probe tip. The specimen prepared by this workflow enable a stable measurement and low fracture rates. Research Highlights: Enabling cryo‐preparation of (nano)particles for the atom probe.Characterization of surface and bulk elemental distribution of GaPt model SCALMS. [ABSTRACT FROM AUTHOR]

Although our understanding of lung cancer has significantly improved in the past decade, it is still a disease with a high incidence and mortality rate. The key reason is that the efficacy of the therapeutic drugs is limited, mainly due to insufficient doses of drugs delivered to the lungs. To achieve precise lung cancer diagnosis and treatment, nano‐particles (NPs) pulmonary delivery techniques have attracted much attention and facilitate the exploration of the potential of those in inhalable NPs targeting tumor lesions. Since the therapeutic research focusing on pulmonary delivery NPs has rapidly developed and evolved substantially, this review will mainly discuss the current developments of pulmonary delivery NPs for precision lung cancer diagnosis and therapy. This article is categorized under:Therapeutic Approaches and Drug Discovery > Nanomedicine for Respiratory DiseaseTherapeutic Approaches and Drug Discovery > Emerging TechnologiesDiagnostic Tools > In Vivo Nanodiagnostics and Imaging [ABSTRACT FROM AUTHOR]

Boehmite nano‐particles with a high degree of surface hydroxyl groups were covalently functionalized by 3‐(trimethoxysilyl)‐propylamine to support H3[PMo12O40], H3[PW12O40], H4[SiMo12O40] and H4[SiW12O40] Keggin‐type heteropolyacids. After characterization of these catalysts by FT‐IR, powder X‐ray diffraction, TG/differential thermal analysis, CHN, inductively coupled plasma and transmission electron microscopy techniques, they were applied to the epoxidation of cis‐cycloocten. The progress of the reactions was investigated by gas–liquid chromatography, and the catalytic procedures were optimized for the parameters involved, such as the solvent and oxidant. The results showed that 25 mg of supported H3[PMo12O40] catalyst in 1 ml C2H4Cl2 with 0.5 mmol cyclooctene and 1 mmol tert‐butylhydroperoxide at reflux temperature gave 98% yield over 15 min. Recycling experiments revealed that these nanocatalysts could be repeatedly applied up to five times for a nearly complete epoxidation of cis‐cycloocten. The optimized experimental conditions were also used successfully for the epoxidation of some other alkenes, such as cyclohexene, styrene and α‐methyl styrene. [ABSTRACT FROM AUTHOR]

The present work aims to improve both the thermal and dielectric properties at power frequency of millable high temperature vulcanized silicone rubber (HTV SR) so that it can be used as housing material for transformer bushings or as a substitute to ceramic and glass insulators. For this purpose, nano sized titanium dioxide (TiO2) particles have been incorporated into HTV SR. Samples of HTV SR, filled with different percentages by weight of nano TiO2 fillers have been synthesized along with one HTV SR sample without filler loading referred here as blank HTV SR sample in the subsequent sections. Morphological characterizations of these nano filler impregnated samples are carried out. Thermal, electrical and mechanical characterizations are performed and the results are compared with those obtained for blank HTV SR samples. Results showed that at lower filler concentrations, dielectric properties and thermal stability of HTV SR/TiO2 nanocomposites have improved to a considerable extent while retaining the mechanical properties. [ABSTRACT FROM AUTHOR]

Novel and stable magnetic mesoporous silica micro‐nano catalyst immobilized with palladium complex of N‐heterocyclic carbene were readily synthesized with a well‐designed process, which exhibited extremely high catalytic activity in Suzuki‐Miyaura cross‐coupling reactions in ethanol. The double‐template micelle system was used to prepare the mesoporous silica coating layer, which has the characteristics of a large specific surface area and adjustable pore size. Remarkably, the catalyst could be recycled 14 times without significant decrease in activity. It reflects the effectiveness of our strategy of combining the activity of N‐heterocyclic carbene (NHC) with specificity of the mesoporous silica to improve the catalyst catalytic activity and load stability. [ABSTRACT FROM AUTHOR]

Copper immobilized on silk fibroin was successfully prepared and fully characterized using powder X‐ray diffraction, scanning electron microscopy–energy‐dispersive X‐ray spectroscopy, Fourier transform‐infrared, CHN elemental analysis, and inductively coupled plasma‐atomic emission spectroscopy. Catalytic activity of this catalyst was examined in the azide‐alkyne cycloaddition reaction with internal and terminal alkynes at room temperature under mild conditions. The reusability of the heterogeneous supported Cu catalyst was examined four times without significant loss of catalytic activity. [ABSTRACT FROM AUTHOR]

Use of nano-materials as lubricant additives is gaining tremendous importance due to their capabilities in enhancing the tribo-performance. The nano-particles of various elements and compounds are efficiently blended in mineral base oils enhancing their physico-chemical as well as tribological properties. However, in recent times due to the environmental concerns, focus is being shifted toward bio based lubricants. Bio lubricants are obtained from plant oil by various chemical modification techniques. They are environment friendly, biodegradable and have better lubricating properties than the mineral oil based counterparts. The major challenge however for these lubricants is the selection of appropriate additives. The commercial additives developed for mineral base oils are generally toxic and not suitable for the Biolubricants. In this context, the present paper attempts to investigate the efficacy of Cu nano-particles as additive for Biolubricants. The non-edible karanja oil has been chemically modified to karanja ester and used as biolubricant. The functionalized Cu nano-particles have been blended in various concentrations in biolubricant and the tribological performance investigated using four ball tribo-tester. In order to ascertain the efficacy of Cu nano-particles as additives, the tribo-performance of Cu nano-particle blended biolubricant has been compared with that of Zinc dialkyl dithio phosphate (ZDDP) blended biolubricant in equal concentrations. ZDDP is a conventional commercially available multi-purpose additive that enhances the tribo-performance of lubricating oils. The comparative study of experimental results showed that ZDDP helps in enhancing the anti-wear performance of bio-lubricant while the Cu nano-particles aided in enhancement of anti-friction behavior of biolubricant. [ABSTRACT FROM AUTHOR]

A novel amphiphilic photoreactive block copolymer was synthesized by electrochemically mediated atom transfer radical polymerization (eATRP) of glycidyl methacrylate (GMA), N-vinyl carbazole (VK) with polyethylene glycol-based initiator (PEG-Br). And then the double bond and the boric acid group were introduced through the epoxy group. Fluorescent molecularly imprinted nanoparticles (nano-FMIPs) were prepared using self-assembly imprinting technology with PEG-b-P(GMA-co-VK) as a functional monomer and sialic acid (SA) as a template molecule. The nano-FMIPs prepared by this method have the advantages of uniform size and small particle size, which greatly improves their recognition performance. It is found that the SA template can significantly quench the fluorescence intensity of nano-FMIPs linearly within a concentration range of 4 x 10-4-4 x 10-6 mol L-1, which is well described by Stern-Volmer equation. The nano-FMIPs can selectively and sensitively detect down to 2.9 µM of SA concentration. This study provides a new and general strategy for the preparation of nano-MIPs with high selective recognition ability in aqueous media, which has good application prospects in biomedicine. [ABSTRACT FROM AUTHOR]

Purpose: The present study was conducted to evaluate the amount of bone height gain, density values, and implant stability after maxillary sinus floor elevation using graftless tenting technique or the use of Hydroxyapatite Nanoparticles bone substitute for augmentation with simultaneous implant placement. Materials and Methods: A total of 20 sinuses with a residual alveolar bone height ranging from 4‐6 mm were divided into two groups and underwent sinus augmentation using nano hydroxyapatite bone substitute material and the graftless tenting technique with simultaneous implant placement. Computed tomography CT scans and ISQ measurements were conducted to evaluate bone quality, quantity, and implant stability. Results: Radiographic analysis revealed that the mean bone height gain of the nano group was (7.0 ± 0.8 mm) compared to (5.0 ± 1.5 mm) in the tent group, which was statistically significant (P =.002) being higher in the nano group. The mean bone density value of the nano group was (548 ± 25 HU) compared to (420 ± 23 HU) in the tent group, which was statistically significant (P <.001) being higher in the nano group. The mean ISQ value after 6 months in the nano group was (78 ± 5) compared to (77 ± 5) in the tent group, which was statistically nonsignificant (P =.901). Conclusion: Nano hydroxyapatite bone graft offered superior results in terms of the bone height gain and the relative bone density as compared to graftless tenting technique. However, both techniques showed accepted results regarding implant stability. [ABSTRACT FROM AUTHOR]

Purpose: Silicone elastomers are generally used for maxillofacial extraoral prostheses. The purpose of this in vitro study was to evaluate the cytotoxicity of different kinds of nanoparticles added to two types of maxillofacial elastomers., Materials and Methods: A-2000 and A-2006 silicone elastomers were used. The silicone specimens were divided into eight groups according to the presence of additional nanoparticles (n = 18). The following represents the groups in the study: Group A: A-2000 silicone (control group); Group B: A-2006 silicone (control group); Group C: A-2000 silicone and the addition of titanium dioxide (TiO 2 ); Group D: A-2006 silicone and the addition of TiO 2 ; Group E: A-2000 silicone and the addition of fumed silica; Group F: A-2006 silicone and the addition of fumed silica; Group G: A-2000 silicone and the addition of silaned silica; Group H: A-2006 silicone and the addition of silaned silica. A paired sample t-test was used to analyze the cytotoxicity of each group after 24, 48, and 72 hours., Results: Based on the results of the 24-hour analysis, the biocompatibility values of the (A-2006) fumed silica group were higher than those of the control groups. There was no statistically significant difference in A-2006 and A-2000 groups. The cytotoxicity values of the control groups and TiO 2 (A-2000 silicone) elastomer groups increased at all test times; however, the cytotoxicity values of the TiO 2 (A-2006), fumed silica (A-2006), silaned silica (A-2006), fumed silica (A-2000), and silaned silica (A-2000) groups increased significantly only from 24 to 48 hours., Conclusion: Nanoparticles of TiO 2 , fumed silica, and silaned silica added to a commercial silicone-based elastomer used for fabrication of maxillofacial prostheses are nontoxic., (© 2016 by the American College of Prosthodontists.)

In this study, citrate-stabilised iron oxide nano-particles (∼16 nm) have been immobilised on commercial silica monolithic centrifugal spin columns (MonoSpin) for the extraction of phosphorylated compounds. Two alternative strategies were adopted involving either direct electrostatic attachment to an aminated MonoSpin (single-layer method) in the first instance, or the use of a layer-by-layer method with poly(diallyldimethylammonium) chloride. Field-emission scanning electron spectroscopy and energy-dispersive X-ray spectroscopy was used for confirming notably higher coverage of nano-particles using the layer-by-layer method (2.49 ± 0.53 wt%) compared with the single-layer method (0.43 ± 0.30 wt%). The modified monolith was used for the selective separation/extraction of adenosine monophosphate, adenosine diphosphate and adenosine triphosphate with elution using a phosphate buffer. A reversed-phase liquid chromatographic assay was used for confirming that adenosine, as a non-phosphorylated control was not retained on the modified MonoSpin devices, whereas recovery of 80% for adenosine monophosphate, 86% for adenosine diphosphate and 82% for adenosine triphosphate was achieved. [ABSTRACT FROM AUTHOR]

Rheological properties of lubricants determine their flow behavior. Rheological parameters like viscosity index (VI), dynamic viscosity, shear stress and strain rate are influenced by dispersing Cu nanoparticles in them. This not only enhances the rheological properties of the lubricants, influences the contact fatigue behavior of steel also due to improved adhesive properties. Synthesis of new materials and additives is a technological marvel of Modern Tribo Chemistry that helps enhance the physicochemical and rheological properties of the lubricants and also enhances the contact fatigue behavior of materials. In order to study the effect of Cu nanoparticles on the rheological properties of lubricants two commercially available blended lubricants were selected as base oils with synthetic engine oils of SAE grades 5W40. They were dispersed with 0.2% of nano-Cu by weight. Physicochemical properties of oils were determined using standard ASTM and IS procedures. The experimental investigations were performed on four-ball sliding contact geometry to assess the anti-friction and anti-wear behavior. Rheological parameters were evaluated using rheometerPhysica MCR 301 from Anton-Paar Austria. Contact fatigue tests were also conducted on four ball fatigue tester using standard ASTM procedure. A significant reduction in friction and wear to the order of less than 13% has been observed for the 0.2 wt% of Cu nano-particles showing enhanced tribological performance of the base oils. Cu nanofluids form boundary films on the metal surfaces which help enhance the tribo performance by reducing friction and wear as confirmed by The SEM and EDX analysis. Also the surface topography of the worn out of used test specimens revealed smooth sliding wear against the severe wear by the base oils. Rheological data reveal that tested Cu nano-fluids behaved as non- Newtonian at low shear rates at all temperatures and at higher shear rates behaved as Newtonian fluids. On plotting the Weibull curves and survival probability curves it was observed that the nano lubricants showed much improved rolling contact fatigue life with an enhancement of L10 life from 16 to 61% and L90 life from 18 to 118%. Characteristic life also showed an improvement upto 117.6%. Moreover survival probability of rolling contacts also showed an improvement in the presence of nano-Cu particles. [ABSTRACT FROM AUTHOR]

Shape sensitivity measures the impact of small perturbations of geometric features of a problem on certain quantities of interest. The shape sensitivity of PDE (partial differential equation) constrained output functionals is derived with the help of shape gradients. In electromagnetic scattering problems, the standard procedure of the Lagrangian approach cannot be applied because of solution of the state problem is complex valued. We derive a closed-form formula of the shape gradient of a generic output functional constrained by Maxwell's equations. We employ cubic B-splines to model local deformations of the geometry and derive sensitivity probings over the surface of the scatterer. We also define a sensitivity representative function over the surface of the scatterer on the basis of local sensitivity measurements. Several numerical experiments are conducted to investigate the shape sensitivity of different output functionals for different geometric settings. [ABSTRACT FROM AUTHOR]

Abstract: Energy release rate and fracture toughness of amorphous aluminum nanoparticles reinforced soda‐lime silica glass (SLSG) were measured by performing fracture simulations of a single‐notched specimen via molecular dynamics simulations. The simulation procedure was first applied to conventional oxide glasses and the accuracy was verified with comparing to experimental data. According to the fracture simulations on three models of SLSG/‐Al2O3 composite, it was found that the crack propagation in the composites is prevented through following remarkable phenomena; one is that a‐Al2O3 nanoparticles increase fracture surface area by disturbing crack propagation. The other is that the deformation of a‐Al2O3 nanoparticle dissipates energy through cracking. Moreover, one of the models shows us that the crack cannot propagate if the initial notch is generated inside a‐Al2O3 nanoparticle. Such strengthening is partly due to the fact that the strength of the interface between nanoparticle and SLSG matrix is comparable to that of SLSG matrix, implying that their interface does not reduce crack resistance of the oxide glass. [ABSTRACT FROM AUTHOR]

Abstract: Gene therapy depends on the perfect DNA delivery to the nuclear subdomain, where DNA should be orchestrated in a lipid based programmed packaging, like multi‐functional envelope type of nano device (MEND) and tetra lamellar multi‐functional envelope type of nano device (T‐MEND) published elsewhere. In both the packaging system, DNA has to make a complex (core) with a cationic polymer. It is important how about the effect of such a DNA/condenser core inside the programmed‐packaging reflects the transgene expression. Here we compared transgene expression of a firefly luciferase gene from both the protaplex (protamine‐DNA) and rotaplex (polyrotaxane‐DNA), packaged in MENDs. Dendritic cells were transfected with these nanoparticles and transgene expression, cell viability as well as antigen presentations were measured. Transgene expression from the MEND of protaplex was significantly higher in JAWs‐II cell (dendritic cell line) and bone marrow dendritic cell. Cell viability and antigen presentations from the protaplex were also prompt and better than that of polyplex, when T‐MEND package systems containing protaplex and rotaplex, were compared. Confocal microscopic studies of fluorescently labeled plasmid DNA reflected the evidence of ease decondensation of DNA from the protaplex than that of a rotaplex. Our results suggest that a natural DNA condenser (protamine in protaplex) prefers transgene expression better to those of synthetic polycationic condenser (polyrotaxane in rotaplex). [ABSTRACT FROM AUTHOR]

Nano Fe3O4 particles were obtained in microvawe oven using closed system. Oxovanadium(IV) complexes of Fe3O4@SiO2@(aminomethylphosphine) type ligands were synthesized and characterized using SEM, EDX, TEM, UV‐Visible, XRD, FT‐IR and TG/DTA techniques. Catalytic properties of the synthesized pincer type oxovanadium(IV)‐aminomethylphosphine complexes supported on magnetic nano structure were investigated in the synthesis of 2‐methyl‐1, 4‐naphthoquinone (Vitamin K3, menadione, 2MNQ) from 2‐methyl naphthalene (2MN) in hydrogen peroxide, acetic acid and sulfuric acid. Magnetic‐nano particle supported oxovanadium(IV)‐aminomethylphosphine type complexes were very efficient catalysts with the 51.36‐55.20 % selectivities in conversions of 89.78‐95.01 %. Besides, the hetergeneous complexes were very active in five cycling tests on avarage evaluated in the reusability. [ABSTRACT FROM AUTHOR]

Transmission electron microscopy (TEM), optic microscopy (OM), and small-angle- X-ray-scattering(SAXS)are combined to comprehensively characterize the effect of endogenous nano-particles obtained by a new method, on microstructure and mechanical properties of the ferritic steel. Morphology of nano-particles, the change of microstructure, and the performance of steel are systematically studied. Results indicate that the endogenous nano-particles are titanium oxide which not only has a positive effect on refining the structure of ferrite steel, but also can significantly improve its strength without much losing its plasticity. Tensile tests reveal that tensile strength and yield strength of the investigated steel are increased from the original 392 and 247 MPa to 524 and 430 MPa, respectively. However, the value of the elongation-to-failure is only decreased by 3%, reached to 25% ultimately. [ABSTRACT FROM AUTHOR]

Abstract: Cu−Co based catalysts for ethanol synthesis (ES) directly from syngas requires that copper and cobalt should be in alloy state or in close contact with each other, the chemical state of the bimetallic Cu−Co should be tailored by more than one additives and the group composed of Cu−Co and the additives should be loaded on a support with high surface area. In this work, a strategy for design and preparing such kind of complex catalysts was proposed, by means of loading nano crystallites of La1‐xYxCo1‐yCuyO3 with perovskite phase on SiO2 and then reducing La1‐xYxCo1‐yCuyO3/SiO2. In a nano crystallite of La1‐xYxCo1‐yCuyO3, the ions of copper and cobalt are uniformly mixed at the atomic level and confined in the nano space, favoring the interaction between the reduced products of Cu, Co, La2O3 and Y2O3. Thus, prepared catalyst showed very good catalytic performance for ES. This preparation strategy should be extendable. [ABSTRACT FROM AUTHOR]

The utility of green silver nanoparticles (AgNPs) in veterinary medicine is steadily increasing as they have many therapeutic applications against pathogens and arthropods of livestock. In this study, green AgNPs using neem (N-AgNPs), 2,3- dehydrosalanol (2,3-DHS-AgNPs) and quercetin dihydrate (QDH-AgNPs) were synthesised and characterised. Synthesised compounds were characterised by UV-Vis spectroscopy and the peak absorbance was recorded at 370 nm for neem extract. For N-AgNPs, 2,3-DHS-AgNPs and QDH-AgNPs, the maximum absorbance peaks were at 430, 230 and 220 nm, respectively. The FTIR analysis confirmed the synthesis of green AgNPs. The XRD pattern of N-AgNPs showed the peaks corresponding to whole spectra of 2 θ values ranging from 10-80. The relatively higher intensity of (111, 222) planes in face centred cubic crystalline structure supports the formation of synthesised AgNPs. In DLS analysis, the hydrodynamic diameter of neem leaf extract was found to be 259.8 nm, followed by 5.3, 6.7 and 261.8 nm for 2,3-DHS-AgNPs, N-AgNPs and QDH-AgNPs, respectively. Based on the transmission electron microscopy and scanning electron microscopy image analyses, confirmed the formation of N-AgNPs, 2,3-DHS-AgNPs and QDH-AgNPs. These eco-friendly phyto-AgNPs may be of use as an effective alternative to chemical control methods against the arthropods of livestock. [ABSTRACT FROM AUTHOR]

Islet cell transplantation is a promising option for the restoration of normal glucose homeostasis in patients with type 1 diabetes. Because graft volume is a crucial issue in islet transplantations for patients with diabetes, we evaluated a new method for increasing functional tissue yield in xenogeneic grafts of encapsulated islets. Islets were labeled with three different superparamagnetic iron oxide nano particles ( SPIONs; dextran-coated SPION, siloxane-coated SPION, and heparin-coated SPION). Magnetic separation was performed to separate encapsulated islets from the empty capsules, and cell viability and function were tested. Islets labeled with 1000 μg Fe/ml dextran-coated SPIONs experienced a 69.9% reduction in graft volume, with a 33.2% loss of islet-containing capsules. Islets labeled with 100 μg Fe/ml heparin-coated SPIONs showed a 46.4% reduction in graft volume, with a 4.5% loss of capsules containing islets. No purification could be achieved using siloxane-coated SPIONs due to its toxicity to the primary islets. SPION labeling of islets is useful for transplant purification during islet separation as well as in vivo imaging after transplantation. Furthermore, purification of encapsulated islets can also reduce the volume of the encapsulated islets without impairing their function by removing empty capsules. [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the effects of nanoparticles on plasticizers volatility, solvent extraction stability and exudation stability of polyvinyl chloride (PVC). It notes various ways by which PVC plasticizers can be released from PVC including extraction from PVC to a liquid and migration from PVC to a solid or semi-solid. Results of the study showed that migration of plasticizers can be reduced by nanoparticles.

ABSTRACT In the present paper, hierarchically structured ultrafiltration polysulfone (PSf) membrane was prepared to explore the effect of addition and subsequent removal of SiO2 nano-particles on the membrane morphology, hydrophilicity, and separation properties. The PSf based membranes namely PSf, PSf/SiO2 and PSf/WSiO2 (i.e. SiO2 nano-particles was acid-washed and removed from PSf/SiO2), were synthesized and characterized by different characterization methods. Pure water flux through the membranes was determined using a filtration unit operating at a continuous dead-end flow mode. The modification enhanced the morphology, hydrophobicity, porosity and transport properties of the modified membranes, although the molecular weight cut-off (MWCO) of the membranes was not changed considerably. In comparison, PSf/WSiO2 membrane exhibited excellent pure water flux (about 4.5 times the flux of PSf, and 17 times the flux of PSf/SiO2), although antifouling property of PSf/SiO2 in separation of bovine serum albumin (BSA) was better than that of PSf and PSf/WSiO2 membranes. The results suggested that the addition/removal of sacrificial solid fillers within/from a membrane matrix may provide a promising strategy to enhance PSf membrane transport property. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43556. [ABSTRACT FROM AUTHOR]

Many studies focus on nanoparticles as lubricity additives but overlook the fact that wear produces nanosized debris during the field use. In order to simulate the fine metal contaminants, which are the most widespread in various field applications, prefabricated Fe, Cu and Zn nanoparticles were used. Their 0.01-1% suspensions in vegetable and mineral oils with or without ZDDP and ashless AW package were tested on four-ball AW under 150-N load. Tribological effects of nanoparticles were not significant in formulations without AW additives. However, nanoFe addition produced notable lubricity improvement in already excellently performing rapeseed formulation with ZDDP, while such addition reduced performance of the ashless AW pack. Results show that metal nanoparticles can play both positive and negative roles on additive effectiveness and nanosized contaminants can significantly affect the lubricant performance. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Aluminum‐silicon alloys have been widely used in automotive industries. To know mechanical properties of such materials is essential for engineers to have a superior design for components. Therefore, in this article, the sensitivity analysis of mechanical and fracture features in the aluminum alloy has been performed to find the effect of the loading rate and nano‐particles. For this objective, tensile tests were performed on casting standard specimens. Then, obtained experimental data were analyzed by the Minitab software, using the factorial method. In addition, the interaction between the effect of the loading rate and the addition of nano‐particles, on mechanical properties and ductile/brittle behaviors, was also investigated. Obtained results indicated that the yield stress, the elastic modulus and the elongation were sensitive to the interaction of both factors (the multiply of the nano‐particle addition and the loading rate). Besides, the fracture surface illustrated that by increasing the loading rate and the addition of nano‐particles, the brittleness of the material increased. [ABSTRACT FROM AUTHOR]

In the current research work, zinc oxide nano particles are synthesized by simple precipitation method and studied its antibacterial activity. The antibacterial activity can be successfully enhanced for some kind of bacterium after the addition of eucalyptus leaves extract. The structural, morphological, and elemental properties of synthesized material and the effect of eucalyptus leaves extract on these properties are studied by using X‐ray diffraction (XRD), Field Emission Scanning electron Microscopy (FESEM), and elemental analysis (EDAX). Enhanced crystalline size and porosity is observed after the addition of eucalyptus leaves extract while synthesizing zinc oxide (ZnO). In addition, eucalyptus leaves extract assists to avoid agglomeration of ZnO nano particles. Role of eucalyptus leaves extract in the antibacterial activity of synthesized ZnO nano particles are studied against gram positive bacterium (Bacillus) and gram negative bacterium (Escherichia coli). It reveals that after addition of eucalyptus leaves extract, antibacterial activity against gram positive bacteria (Bacillus) is enhanced. However, it does not show any antibacterial activity on a gram negative bacterium (E. coli). The eucalyptus leaves extract may be responsible for the resistance against E. coli. [ABSTRACT FROM AUTHOR]

As a new product of high‐value utilization of lignin, lignin micro/nano particles (LMNPs) have attracted the attention of researchers due to their non‐toxicity, corrosion‐resistance, UV resistance, and other excellent characteristics and potential application value. This article outlined the main preparation methods of LMNPs at the current stage, summarized and compared them from three perspectives of preparation technology, final product state and product composition. Subsequently, based on the different focuses of the properties of LMNPs, their application research progress as fillers, UV blockers, drug delivery carriers, among others, were introduced. Then a concise analysis of the technical and economic assessment and life cycle assessment of LMNPs in the process of industrialization was made. Finally, the main problems at present and the future development directions were analyzed and prospected to provide references for the deep processing of forest resources and the development of bio‐based nanomaterials. [ABSTRACT FROM AUTHOR]

In the past few years, people have put forward higher and higher requirements for the performance of liquid crystal displays, such as higher refresh rate and picture continuity which requires liquid crystal displays having lower threshold voltage and shorter response time. In order to study the electro‐optical properties of liquid crystal display, the experiments was designed to dope SiO2 nano‐particles into the SD1 solution and to observe the impact on the threshold voltage, the electrical response time and the rewriting time of the optically driving liquid crystal display (ODLCD). The experiment results show that doping SiO2 nano‐particles in the liquid crystals can reduce the threshold voltage, the electrical response time and the rewriting time of ODLCD. [ABSTRACT FROM AUTHOR]

In this research study, a comprehensive effort has been made to functionalize silicon carbide particles using the acidic oxidation with nitric acid to obtain homogeneous stabilized distribution of activated SiC particles within a polymer matrix, and develop functionalized silicon carbide (f‐SiC) particle reinforced polyvinyl alcohol (PVA) based cross‐linked composite. After fabrication of functionalized silicon carbide (f‐SiC) particle reinforced polyvinyl alcohol based cross‐linked composite with varying f‐SiC weight percentages of PVA (0%, 1%, 2%, 3%, and 4%) were placed to various investigations. Processed samples are initially examined based by the physical tests (water absorption tests), followed by mechanical test (tensile test) and then micro‐structural tests (scanning electron microscopy). Lastly, thermal tests were also concluded which involved the dynamic mechanical, differential thermal and thermo gravimetric analysis. The cross‐linked polyvinyl alcohol‐based composite with 2 weight % of f‐SiC content is observed to be the superlative of all the compositions under this research study that was confirmed by the mechanical and micro‐structural tests. This composite material shows high storage modulus with visco‐elastic behavior, therefore, the material can be utilized to diminish the transmission of noise, as a shock absorber and vibration isolator. [ABSTRACT FROM AUTHOR]

High-purity nanoparticles ZnS has been successfully synthesized using a simple coupling reaction process of biological reduction and chemical precipitation mediated with EDTA referred to as the CRBRCP-EDTA process. This research investigated the optimum conditions of the transformation of SO(4) (2-) into S(2-) by SRB, and the production of ZnS in the CRBRCP-EDTA process. The results showed that the molar ratio of Zn(2+) to EDTA = 1:1 was crucial for SRB growth and ZnS synthesis. At the ratio(n) (Zn2+)/n) (EDTA) = 1:1, lower Zn(2+) concentration enhanced both the growth of SRB and the reduction of SO(4) (2-), leading to higher ZnS production. Although increase in Na(2)SO(4) concentration resulted in decrease in both SRB growth and SO(4) (2-) reduction, it improved the S(2-) and ZnS production. Under the optimum conditions (0.05 mol L(-1) ZnCl(2), 0.05 mol L(-1) EDTA, and 0.1 mol L(-1) Na(2)SO(4)), the synthesized ZnS was characterized by X-ray diffraction (XRD), X-ray energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The analysis showed that the obtained ZnS were high-purity and well-distributed solid spheres with diameters of about 15 nm for primary particles and around 400 nm for secondary particles. When polyacrylamide (PAM) was incorporated in the CRBRCP-EDTA process, the secondary particle's diameters were reduced to less than 100 nm. The photoluminescence (PL) spectra of produced ZnS centered at 396 nm, the spectrum with PAM added showed the gradual increase in absorption and stronger intensity in PL property. The present simple, low-cost, and safe method may be extended to prepare other metal-sulfide nanocomposites.

3D biomaterial printing requires an ink to have suitable printability characteristics, as well as creating a final construct of controllable swelling and stiffness. To tune such properties, the impact of adding different levels of chloride salts (NaCl and CaCl2) and hydroxyapatite nano‐particles (nHA) to a highly concentrated and photo‐crosslinkable methacrylated gelatin (GelMA) is investigated. By adding up to 100 mm CaCl2 or 1.11 m NaCl, the GelMA viscosity decreases from that of control GelMA (no salt). Interestingly, a 25G needle and strong photo‐polymerization kinetics are able to overcome the low viscosity of the 50CaG ink during printing. Adding further CaCl2 increases GelMA viscosity, while decreasing both the swelling and dynamic modulus of the UV‐cured construct observed in water. As all UV‐cured constructs have a dynamic modulus greater than 1 MPa, this novel system is able to match the dynamic modulus of articular cartilage—a feat not previously reported for a GelMA‐based system. Lastly, nHA inclusion improves ink printability, as well as decreases swelling and increases dynamic modulus of the final construct. Overall, this study leads to the successful development of a new advanced functional ink which will be beneficial in the 3D printing of biomaterials toward tissue engineering applications. [ABSTRACT FROM AUTHOR]

This review describes the formation of a protein corona (or its absence) on different classes of nanoparticles, its basic principles, and its consequences for nanomedicine. For this purpose, it describes general concepts to control (guide/minimize) the interaction between artificial nanoparticles and plasma proteins to reduce protein corona formation. Thereafter, methods for the qualitative or quantitative determination of protein corona formation are presented, as well as the properties of nanoparticle surfaces, which are relevant for protein corona prevention (or formation). Thereby especially the role of grafting density of hydrophilic polymers on the surface of the nanoparticle is discussed to prevent the formation of a protein corona. In this context also the potential of detergents (surfactants) for a temporary modification as well as grafting‐to and grafting‐from approaches for a permanent modification of the surface are discussed. The review concludes by highlighting several promising avenues. This includes (i) the use of nanoparticles without protein corona for active targeting, (ii) the use of synthetic nanoparticles without protein corona formation to address the immune system, (iii) the recollection of nanoparticles with a defined protein corona after in vivo application to sample the blood proteome and (iv) further concepts to reduce protein corona formation. [ABSTRACT FROM AUTHOR]

MCM-41 micro- and nanoparticles are prepared and functionalized with silane coupling agents. These pristine and silane-decorated mesoporous MCM-41s are further used in the synthesis of MCM-41/ethylene nanocomposites by in situ polymerization, utilizing either supported or non-supported catalytic systems. The catalytic behavior of those systems is discussed, taking into consideration the effects of the particle size, surface characteristics, and functionalization. The results have shown that the initial surface state of MCM-41 is of paramount importance to achieve high catalytic activity if a polymerization catalyst is to be supported. Functionalization changes the surface chemistry, thus, a positive or negative effect may be observed, depending on the previous features of the surface. The particle size of MCM-41 and its functionalization affect its final dispersion within the polymeric matrix, this distribution is evaluated by SEM, TEM, and microhardness measurements. [ABSTRACT FROM AUTHOR]

The present study describes the detection and localization of silica particles with diameters between 2 µm and 150 nm within the cytoplasm of mammalian cells by means of ToF-SIMS 3D analysis. The particles were selected as model objects for non-luminescent, unlabeled particles that are hard to localize by other experimental approaches. ToF-SIMS analysis proved the uptake of the particles into the cell body, provided images of their distribution around the cell nucleus and indications that the cell membranes are undulated by the µm-sized particles beneath the membrane. Two ion sources (Cs+ and O2+) were applied for sputtering the organic material and expose deeper sections of the cells. The resulting images are presented and compared. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]