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transfer using alumina particles compared to the conventional fluid. Das et al. [ 13 ] experimentally studied the effect of adding alumina nanoparticles based water nanofluid on the behavior of the pool-boiling curve and heat transfer coefficient from

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are microemulsions, nanoemulsion, self-emulsifying drug delivery system, solid–lipid nanoparticles (SLN), vesicular system, such as transfersomes, liposomes, etc. LBDDS presents an opportunity for formulation scientists to overcome several challenges

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Synthesis of silver nanoparticles (NPs) in an impinging jet reactor (IJR) was investigated due to its unique properties of efficient mixing and lack of channel walls which avoid fouling. Silver NPs were formed at room temperature by reducing silver nitrate with sodium borohydride in the presence of sodium hydroxide. Two types of ligand were used to stabilize the NPs, trisodium citrate, and polyvinyl alcohol (PVA). Weber number, the ratio between inertial forces and surface tension forces, is used to characterize flow in impinging jets. Flow regimes were investigated forWeber numbers in the range of 13–176. A liquid sheet/chain regime was identified at lowerWeber numbers (<90), and an unstable rim structure was identified at higherWeber numbers (>90). Mixing time was found to be in the range 1–7ms, using theVillermaux—Dushman reaction system and interaction by exchange with the mean mixing (IEM) model. Fastest mixing occurred at Weber number ca. 90. Using trisodium citrate as a ligand, NP size decreased from 7.9 ± 5.8 nm to 3.4 ± 1.4 nm when flow rate was increased from 32 mL/min to 72 mL/min using 0.5 mm jets, and from 6.4 ± 3.4 nm to 5.1 ± 4.6 nm when flow rate was increased from 20 mL/min to 32 mL/min using 0.25 mm jets. Using PVA as a ligand, NP size decreased from 5.4 ± 1.6 nm to 4.2 ± 1.1 nm using 0.5 mm jets and stayed relatively constant between 4.3 ± 1 nm and 4.7 ± 1.3 nm using 0.25 mm jets. In general, the size of the NPs decreased when mixing was faster.

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lunar samples from Apollo 11, 12 and 16 missions were personally examined. The thickness of the adsorbed liquid layers (adsorption capacity) and adsorbate–adsorbente interactions (desorption energy) on the lunar nanoparticles can be assessed by means of

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This paper presents a new route to the synthesis of uniform and size-controlled inorganic/organic composite microparticles by means of microreaction technology. Au-nanoparticles in the range of 3 to 14 nm are synthesized by reduction of tetrachloroauric acid, while ZnO-nanoparticles (200–2000 nm) are synthesized in a continuous-flow two-step process using microtube arrangements for microsegmented flow. Both inorganic nanoparticles have a well-controlled size and narrow size distribution. Upon surface modification, the nanoparticles are then mixed on one hand with an acrylate-based monomer and, on the other hand, with an aqueous solution of acrylamide. Both solutions were then emulsified into uniform core-shell droplets by means of a capillary-based microfluidic device. Droplet's shell was hardened through UV-induced polymerization, whereas the core led to a hydrogel upon thermal-induced polymerization. Core-shell polymer microparticles (200–300 µm) with inorganic nanoparticles selectively incorporated into the core and the shell are thus obtained as proven by extensive morphological characterizations using electronic and optical microscopies.

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High-performance thin-layer chromatography (HPTLC) method for the quantification of eugenol from nanostructured drug delivery systems was successfully developed and validated. The mobile phase consisted of n-hexane:acetone (7:3, v/v), and the densitometric scanning was performed in the absorbance mode at 280 nm. The method was valid with respect to linearity and range, accuracy, precision, specificity, detection limit (DL), and quantitation limit (QL). The linearity of the method was established by a correlation coefficient value of 0.9930 ± 0.0013. The precision was tested by checking intra-day (repeatability) and inter-day (intermediate precision) variations. The method was established to be precise by low relative standard deviation (RSD) values for different concentration of eugenol. The results of the recovery studies of eugenol from preanalyzed samples demonstrated the accuracy of the method. The specificity of the developed method for the analysis of eugenol in the nanoemulsion gel and nanoparticles samples was confirmed by comparing the spectra obtained in standard and sample analysis. The DL and QL were determined to be 31.41 and 95.17 ng band−1, respectively, for the HPTLC method. The forced degradation studies revealed on eugenol established the effectiveness of the developed and validated method. The developed and validated HPTLC method was found to be a stability-indicating one, as indicated by the results of forced degradation studies, for its use during the accelerated stability studies of the nanoemulsion gels and nanoparticles of eugenol.

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The real-time monitoring of the adsorption kinetic of antibody onto polyethylene terephthalate (PET) modified with gold nanoparticles (NPs) is performed into a dielectric flow microchannel. The principle is based on the microelectrode–dielectric interface excitation by a modulated voltage excitation through the dielectric layer with high frequency range. The set-up configuration using a homemade current-to-voltage converter has been developed for fast monitoring of biomolecule adsorption without direct electrical contact of microelectrodes with the microchannel flow. The change in the interfacial admittance, related to the output voltage measured through the microchip, during antibody incubation, gives information on the kinetics involved while antibodies are adsorbed at the interface. An example of adsorption on PET modified with gold NPS was taken. Experimental data were fit with the Langmuir equation and a good correlation was obtained with this latter, where the equilibrium constant, K, was found as 1.55 × 108 M−1 with a limit of detection for antibody concentration without depletion equal to 8.25 nM.

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Orvosi Hetilap
Authors: Tamara Horváth, András Papp, Mónika Kiricsi, Nóra Igaz, Vivien Trenka, Gábor Kozma, László Tiszlavicz, Zsolt Rázga, and Tünde Vezér

References 1 Buzea C, Pacheco II, Robbie K. Nanomaterials and nanoparticles: sources and toxicity. Biointerphases 2007; 2: MR17–MR71. 2 Keller AA

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about nanotechnology: Risks, benefits and trust . Journal of Nanoparticle Research 6 ( 4 ): 395 . [Serial on the Internet, cited December 26, 2015]; Available from: Publisher Provided Full Text Searching File. [7

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Nanopages
Authors: Elena Burakova, Alexandr Melezhyk, Alyona Gerasimova, Evgeny Galunin, Nariman Memetov, and Alexey Tkachev

) Electromagnetic interference shielding efficiency of polyaniline composites filled with graphene decorated with metallic nanoparticles . Compos Sci Technol 80 80 – 86 . [7] Cong

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