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Search for "UV–vis spectroscopy" in Full Text gives 148 result(s) in Beilstein Journal of Nanotechnology.

Facile synthesis of water-soluble carbon nano-onions under alkaline conditions

  • Gaber Hashem Gaber Ahmed,
  • Rosana Badía Laíño,
  • Josefa Angela García Calzón and
  • Marta Elena Díaz García

Beilstein J. Nanotechnol. 2016, 7, 758–766, doi:10.3762/bjnano.7.67

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  • leaves (acer saccharum), under the same temperature and alkaline conditions did not produce carbon onions. XRD, FTIR, HRTEM, UVvis spectroscopy, and photoluminescence analyses were performed to characterize the as-synthesized carbon nanomaterials. Preliminary tests demonstrate a capability of the
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Published 27 May 2016

Gold nanoparticles covalently assembled onto vesicle structures as possible biosensing platform

  • M. Fátima Barroso,
  • M. Alejandra Luna,
  • Juan S. Flores Tabares,
  • Cristina Delerue-Matos,
  • N. Mariano Correa,
  • Fernando Moyano and
  • Patricia G. Molina

Beilstein J. Nanotechnol. 2016, 7, 655–663, doi:10.3762/bjnano.7.58

Graphical Abstract
  • order to covalently bind the AuNPs to the bilayer and to immobilize the vesicle on the Au electrode. This nanosystem was characterized by using UVvis spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS) and cyclic voltammetry (CV). The results show that the vesicles were
  • sensible to the conditions under which they are formed. As the irradiation time modifies the nanoparticle morphology we decided to irradiate for longer time, in this case, 13 min. Some techniques, such as UVvis spectroscopy and TEM were used to perform the morphological characterization of the AuNPs
  • measurements can be statistically significant for all the systems investigated. The algorithm used was CONTIN and the DLS experiments shown that the polydispersities of the LUVs were less than 5%. UVvis spectroscopy In order to study the formation of AuNPs, UV–vis studies were performed by using Shimadzu 2401
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Published 02 May 2016

Bacteriorhodopsin–ZnO hybrid as a potential sensing element for low-temperature detection of ethanol vapour

  • Saurav Kumar,
  • Sudeshna Bagchi,
  • Senthil Prasad,
  • Anupma Sharma,
  • Ritesh Kumar,
  • Rishemjit Kaur,
  • Jagvir Singh and
  • Amol P. Bhondekar

Beilstein J. Nanotechnol. 2016, 7, 501–510, doi:10.3762/bjnano.7.44

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  • nonhybrid structures, as is evident from Figure 2c,d. The structural and optical properties of ZnO-TF, ZnO-NR and their hybrid structures were assessed using UVvis spectroscopy, photoluminescence spectroscopy (PL), Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR). Figure 3 shows the
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Published 04 Apr 2016

Hemolysin coregulated protein 1 as a molecular gluing unit for the assembly of nanoparticle hybrid structures

  • Tuan Anh Pham,
  • Andreas Schreiber,
  • Elena V. Sturm (née Rosseeva),
  • Stefan Schiller and
  • Helmut Cölfen

Beilstein J. Nanotechnol. 2016, 7, 351–363, doi:10.3762/bjnano.7.32

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  • gluing unit for the assembly of often linear, hybrid structures of plasmonic gold (Au NP), magnetite (Fe3O4 NP), and cobalt ferrite nanoparticles (CoFe2O4 NP). Furthermore, the assembly of Au NPs into linear structures using Hcp1_cys3 is investigated by UVvis spectroscopy, TEM and cryo-TEM. One key
  • nanomaterials. Furthermore, kinetic investigation of the formation of such 1D Au NP structures and the utilization of this structure, for example, as a SERS template and catalyst are also of great interest. The formation kinetics of Au NP networks triggered by Hcp1_cys3 is investigated using UVvis spectroscopy
  • chains, resulting in three protein-based NP hybrid structures on the meso- and micro-scale. The Au NP Hcp1_cys3 assemblies show the formation of short chains in the nanometer range which grow to longer branched chains in UVvis spectroscopy and TEM/cryo-TEM kinetic investigations. Finally, a network
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Published 04 Mar 2016

Time-dependent growth of crystalline Au0-nanoparticles in cyanobacteria as self-reproducing bioreactors: 2. Anabaena cylindrica

  • Liz M. Rösken,
  • Felix Cappel,
  • Susanne Körsten,
  • Christian B. Fischer,
  • Andreas Schönleber,
  • Sander van Smaalen,
  • Stefan Geimer,
  • Christian Beresko,
  • Georg Ankerhold and
  • Stefan Wehner

Beilstein J. Nanotechnol. 2016, 7, 312–327, doi:10.3762/bjnano.7.30

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  • electron microscope. These images reveal the spatial distribution of the nanoparticles inside the cells as it was in the moment when their biosynthesis was stopped. Laser-induced breakdown spectroscopy In recent years UVvis spectroscopy has often been used for the in situ observation of nanoparticle or
  • nanocluster development [46][47][48] of various metals, e.g., palladium, gold and silver [46]. Although UVvis spectroscopy based methods have been developed to determine the size of nanoparticles resp. nanoclusters in solution [47][48]. UVvis spectroscopy was also tested for the type of system used here in
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Published 02 Mar 2016

Single-molecule mechanics of protein-labelled DNA handles

  • Vivek S. Jadhav,
  • Dorothea Brüggemann,
  • Florian Wruck and
  • Martin Hegner

Beilstein J. Nanotechnol. 2016, 7, 138–148, doi:10.3762/bjnano.7.16

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  • kb DNA ladder (NEB & Promega). We utilized UVvis spectroscopy (Nanodrop spectrophotometer ND-1000, Fisher Scientific, Dublin, Ireland) to measure the concentration of the DHs and PDH constructs. These measurements were also indicative for the presence of protein after 90 min of incubation and the
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Published 29 Jan 2016

Impact of ultrasonic dispersion on the photocatalytic activity of titania aggregates

  • Hoai Nga Le,
  • Frank Babick,
  • Klaus Kühn,
  • Minh Tan Nguyen,
  • Michael Stintz and
  • Gianaurelio Cuniberti

Beilstein J. Nanotechnol. 2015, 6, 2423–2430, doi:10.3762/bjnano.6.250

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  • , the transmittance of the 100× diluted samples from the original 1 g/L suspensions were measured. In order to measure the amount of MB remaining in the solution for the discoloration tests, we measured the absorbance in the supernatant suspensions through 10 mm optical path length by UVvis
  • spectroscopy. The MB concentrations were calibrated from the absorbance at λ = 664 nm [19] (the calibration curve can be found in Figure S2 of Supporting Information File 1) and are plotted as a function of irradiation time. Results and Discussion Verification of the kinetic model In essence, an increase of
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Published 17 Dec 2015

Green synthesis, characterization and catalytic activity of natural bentonite-supported copper nanoparticles for the solvent-free synthesis of 1-substituted 1H-1,2,3,4-tetrazoles and reduction of 4-nitrophenol

  • Akbar Rostami-Vartooni,
  • Mohammad Alizadeh and
  • Mojtaba Bagherzadeh

Beilstein J. Nanotechnol. 2015, 6, 2300–2309, doi:10.3762/bjnano.6.236

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  • concentration of 4-NP was monitored at given intervals by using UVvis spectroscopy and the results are shown in Figure 9. The original absorption peak of 4-NP is centered at about 320 nm and shifts to 400 nm after addition of the NaBH4 solution. This is due to the formation of p-nitrophenolate ions under
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Published 03 Dec 2015

Selective porous gates made from colloidal silica nanoparticles

  • Roberto Nisticò,
  • Paola Avetta,
  • Paola Calza,
  • Debora Fabbri,
  • Giuliana Magnacca and
  • Dominique Scalarone

Beilstein J. Nanotechnol. 2015, 6, 2105–2112, doi:10.3762/bjnano.6.215

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  • range 1–2 nm, probably due to intraparticle voids generated from the elimination of poly(ethylene-oxide) moieties during the calcination step [41]. Transport testing of the functional coating UVvis spectroscopy was used to study the diffusion of two positively charged chemical probes (i.e., MB and
  • Aquamarijn Micro Filtration BV (Zutphen, Netherlands), having on top a Si3N4 membrane (5 mm × 5 mm × 0.6 mm) with macropores arranged in a hexagonal setting and diameter of 5 μm. Supporting Information Supporting Information File 144: External calibration curves performed by UVvis spectroscopy
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Published 04 Nov 2015

A facile method for the preparation of bifunctional Mn:ZnS/ZnS/Fe3O4 magnetic and fluorescent nanocrystals

  • Houcine Labiadh,
  • Tahar Ben Chaabane,
  • Romain Sibille,
  • Lavinia Balan and
  • Raphaël Schneider

Beilstein J. Nanotechnol. 2015, 6, 1743–1751, doi:10.3762/bjnano.6.178

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  • heterostructures were characterized by X-ray diffraction (XRD), dynamic light scattering (DLS), transmission electron microscopy (TEM), UVvis spectroscopy and photoluminescence (PL) spectroscopy. The PL spectra of Mn:ZnS/ZnS/Fe3O4 quantum dots (QDs) showed marked visible emission around 584 nm related to the 4T1
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Published 17 Aug 2015

Synthesis, characterization and in vitro biocompatibility study of Au/TMC/Fe3O4 nanocomposites as a promising, nontoxic system for biomedical applications

  • Hanieh Shirazi,
  • Maryam Daneshpour,
  • Soheila Kashanian and
  • Kobra Omidfar

Beilstein J. Nanotechnol. 2015, 6, 1677–1689, doi:10.3762/bjnano.6.170

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  • ) TMC, (c) chitosan/Fe3O4, (d) TMC/Fe3O4, (e) Au/chitosan/Fe3O4, and (f) Au/TMC/Fe3O4. UVvis spectroscopy of Au nanoparticles as a function of (a) Au nanoparticle concentration and (b) reaction time. TEM images of (a) Au/TMC/Fe3O4 and (c) Au/chitosan/Fe3O4 with respective particle size distributions (b
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Published 03 Aug 2015

Synthesis, characterization and in vitro effects of 7 nm alloyed silver–gold nanoparticles

  • Simon Ristig,
  • Svitlana Chernousova,
  • Wolfgang Meyer-Zaika and
  • Matthias Epple

Beilstein J. Nanotechnol. 2015, 6, 1212–1220, doi:10.3762/bjnano.6.124

Graphical Abstract
  • important factor for subsequent in vitro experiments) was carried out by multiple ultracentrifugation steps. Characterization by transmission electron microscopy (TEM), differential centrifugal sedimentation (DCS), dynamic light scattering (DLS), UVvis spectroscopy and atomic absorption spectroscopy (AAS
  • scattering was monitored at a fixed angle of 173° in backward scattering mode. The primary data were derived from the correlation function of the scattered intensity as a number-weighed size distribution. UVvis spectroscopy was performed with a Varian Cary 300 instrument. Suprasil® cuvettes with a sample
  • /Au nanoparticles and pure Ag and Au nanoparticles. Overview of the absorption maxima in UVvis spectroscopy of PVP-functionalized Ag/Au nanoparticles as function of the experimentally determined silver molar content (Table 2). The viability of HeLa cells after incubation with alloyed nanoparticles
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Published 27 May 2015

From lithium to sodium: cell chemistry of room temperature sodium–air and sodium–sulfur batteries

  • Philipp Adelhelm,
  • Pascal Hartmann,
  • Conrad L. Bender,
  • Martin Busche,
  • Christine Eufinger and
  • Juergen Janek

Beilstein J. Nanotechnol. 2015, 6, 1016–1055, doi:10.3762/bjnano.6.105

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Published 23 Apr 2015

Morphology control of zinc oxide films via polysaccharide-mediated, low temperature, chemical bath deposition

  • Florian Waltz,
  • Hans-Christoph Schwarz,
  • Andreas M. Schneider,
  • Stefanie Eiden and
  • Peter Behrens

Beilstein J. Nanotechnol. 2015, 6, 799–808, doi:10.3762/bjnano.6.83

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  • CBD steps, HYA was added at different time intervals in order to optimize the quality of the resulting films. The properties of the films were studied by means of field emitting scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), UVvis spectroscopy and electrical conductivity measurements
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Published 24 Mar 2015

Tm-doped TiO2 and Tm2Ti2O7 pyrochlore nanoparticles: enhancing the photocatalytic activity of rutile with a pyrochlore phase

  • Desiré M. De los Santos,
  • Javier Navas,
  • Teresa Aguilar,
  • Antonio Sánchez-Coronilla,
  • Concha Fernández-Lorenzo,
  • Rodrigo Alcántara,
  • Jose Carlos Piñero,
  • Ginesa Blanco and
  • Joaquín Martín-Calleja

Beilstein J. Nanotechnol. 2015, 6, 605–616, doi:10.3762/bjnano.6.62

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  • spectroscopy and UVvis spectroscopy. For the samples annealed at 773 and 973 K, anatase phase TiO2 was obtained, predominantly internally doped with Tm3+. ICP–AES showed that a doping concentration of up to 5.8 atom % was obtained without reducing the crystallinity of the samples. The presence of Tm3+ was
  • confirmed by X-ray photoelectron spectroscopy and UVvis spectroscopy: the incorporation of Tm3+ was confirmed by the generation of new absorption bands that could be assigned to Tm3+ transitions. Furthermore, when the samples were annealed at 1173 K, a pyrochlore phase (Tm2Ti2O7) mixed with TiO2 was
  • study the optical properties of the samples and to determine the band gap energy, UVvis spectroscopy in diffuse reflectance (DR–UV–vis) mode was used. The custom-built system was composed of: (i) an integrating sphere (Spectra Tech), (ii) a spectrometer (USB2000+, Ocean Optics), and (iii) a xenon lamp
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Published 02 Mar 2015

Novel ZnO:Ag nanocomposites induce significant oxidative stress in human fibroblast malignant melanoma (Ht144) cells

  • Syeda Arooj,
  • Samina Nazir,
  • Akhtar Nadhman,
  • Nafees Ahmad,
  • Bakhtiar Muhammad,
  • Ishaq Ahmad,
  • Kehkashan Mazhar and
  • Rashda Abbasi

Beilstein J. Nanotechnol. 2015, 6, 570–582, doi:10.3762/bjnano.6.59

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  • performing assays, we dialyzed our ZnO:Ag nanocomposite suspensions with Spectra Por 6 (mw cutoff 25000) Spectrum® dialysis membrane for 4 h against deionized water. Characterization of nanocomposite The nanocomposites were characterized by SEM, XRD, Rutherford back scattering, UVvis spectroscopy and DRS
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Published 26 Feb 2015

Silica micro/nanospheres for theranostics: from bimodal MRI and fluorescent imaging probes to cancer therapy

  • Shanka Walia and
  • Amitabha Acharya

Beilstein J. Nanotechnol. 2015, 6, 546–558, doi:10.3762/bjnano.6.57

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  • was then amine-functionalized through APS treatment for bioconjugation with FITC-IgG by using glutaraldehyde as linker. The characterization of the prepared NPs was carried out through XRD, UVvis spectroscopy and PL emission spectra, VSM, TEM and SEM. The fluorescence spectra of mercaptosuccinic-acid
  • vis spectroscopy. The decrease in the absorbance band at 400 nm suggested the successful photogeneration of singlet oxygen. The biocompatibility of these nanocomposites was studied by incubating these nanocomposites with human hepatocyte cells (QSG-7701) for 24 h. The results indicated that even after
  • 2.5 nm. When the hybrid nanocomposite material was excited at 488 nm, it exhibited only one emission peak at 520 nm corresponding to fluorescein. The effectiveness of these nanocomposites to generate singlet oxygen (1O2) upon light irradiation was studied using 1,3-diphenylisobenzofuran (DPBF) by UV
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Published 24 Feb 2015

Raman spectroscopy as a tool to investigate the structure and electronic properties of carbon-atom wires

  • Alberto Milani,
  • Matteo Tommasini,
  • Valeria Russo,
  • Andrea Li Bassi,
  • Andrea Lucotti,
  • Franco Cataldo and
  • Carlo S. Casari

Beilstein J. Nanotechnol. 2015, 6, 480–491, doi:10.3762/bjnano.6.49

Graphical Abstract
  • described in detail in [64]. When the discharge is operated in methanol it is possible to obtain polyynes with an even number of carbon atoms (6 ≤ C ≤ 16) terminated by one hydrogen atom on each side. The size distribution obtained from HPLC complemented with UVvis spectroscopy is reported in Figure 4
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Published 17 Feb 2015

Release behaviour and toxicity evaluation of levodopa from carboxylated single-walled carbon nanotubes

  • Julia M. Tan,
  • Jhi Biau Foo,
  • Sharida Fakurazi and
  • Mohd Zobir Hussein

Beilstein J. Nanotechnol. 2015, 6, 243–253, doi:10.3762/bjnano.6.23

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  • materials characterization methods including Fourier transform infrared spectroscopy, Raman spectroscopy, elemental analysis, UVvis spectroscopy and scanning electron microscopy. The results showed that SWCNT–COOH were able to form supramolecular complexes with LD via a π–π stacking interaction and
  • ≈38.2% as determined by UVvis spectroscopy. Fourier transform infrared spectra indicated that the LD was successfully conjugated to SWCNT–COOH, and this was further supported by both the CHNS elemental analysis and Raman spectroscopy study. The drug release study shows that the release of LD from SWCNT
  • allowed to cool to room temperature for another 30 min. This ensured that the LD was fully dissolved in deionized water. After that, the solution was scanned in range of 200–600 nm to determine the maximum absorption wavelength, λmax, of LD (as referenced to a blank reagent) by UVvis spectroscopy. The
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Published 22 Jan 2015

Mechanical properties of MDCK II cells exposed to gold nanorods

  • Anna Pietuch,
  • Bastian Rouven Brückner,
  • David Schneider,
  • Marco Tarantola,
  • Christina Rosman,
  • Carsten Sönnichsen and
  • Andreas Janshoff

Beilstein J. Nanotechnol. 2015, 6, 223–231, doi:10.3762/bjnano.6.21

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  • of gold nanorods were obtained from UVvis spectroscopy using their optical extinction value at 400 nm and a molar extinction coefficient of 1.1 × 109 Lmol−1cm−1 assuming the aforementioned particle size found by TEM. In order to replace the CTAB, functionalized polyethylene glycol thiols (X-PEG-SH
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Published 20 Jan 2015

Increasing throughput of AFM-based single cell adhesion measurements through multisubstrate surfaces

  • Miao Yu,
  • Nico Strohmeyer,
  • Jinghe Wang,
  • Daniel J. Müller and
  • Jonne Helenius

Beilstein J. Nanotechnol. 2015, 6, 157–166, doi:10.3762/bjnano.6.15

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  • replaced after characterizing 4 cells on each coating. If a cell showed morphological changes during the experiments, it was discarded. Adhesion forces were extracted from force–distance curves using JPK data processing software. Fluorescence microscopy and UVvis spectroscopy Fluorescence microscopy was
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Published 14 Jan 2015

Synthesis of boron nitride nanotubes and their applications

  • Saban Kalay,
  • Zehra Yilmaz,
  • Ozlem Sen,
  • Melis Emanet,
  • Emine Kazanc and
  • Mustafa Çulha

Beilstein J. Nanotechnol. 2015, 6, 84–102, doi:10.3762/bjnano.6.9

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  • normal MRC-5 fibroblast lung cells were investigated [76]. The hemolytic activity of the pure BNNTs was investigated by UVvis spectroscopy and the results showed no significant hemolysis of cells that were exposed to the BNNTs. The metabolic activity of the BNNT-exposed cells using an MTT assay was
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Published 08 Jan 2015

Synthesis and characterization of fluorescence-labelled silica core-shell and noble metal-decorated ceria nanoparticles

  • Rudolf Herrmann,
  • Markus Rennhak and
  • Armin Reller

Beilstein J. Nanotechnol. 2014, 5, 2413–2423, doi:10.3762/bjnano.5.251

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  • the amount of dye molecules at the surface is sufficiently high to be detectable by UVvis spectroscopy, one can in principle use absorption for photometric determination. The problem with this approach is the strong light scattering by the NP which overlays the absorption. We therefore developed a
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Published 16 Dec 2014

Inorganic Janus particles for biomedical applications

  • Isabel Schick,
  • Steffen Lorenz,
  • Dominik Gehrig,
  • Stefan Tenzer,
  • Wiebke Storck,
  • Karl Fischer,
  • Dennis Strand,
  • Frédéric Laquai and
  • Wolfgang Tremel

Beilstein J. Nanotechnol. 2014, 5, 2346–2362, doi:10.3762/bjnano.5.244

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  • oxide domains of the heterodimer nanoparticles were adjusted by a precise control of the precursor ratio, the number of seed particles, and the heating profile. Optical characteristics of Au@MOx Janus particles Figure 10 shows the dependence of the absorption maximum measured by UVvis spectroscopy from
  • size dependency of absorption maximum of Au@MnO nanoparticles determined by UVvis spectroscopy in comparison to pristine Au nanoparticles. UV–vis spectra of Au (solid), Au@MnO (dashed), and Au@Fe3O4 (dotted) nanoparticles normalized to the absorption at 800 nm. Schematic representation of the
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Published 05 Dec 2014

Influence of stabilising agents and pH on the size of SnO2 nanoparticles

  • Olga Rac,
  • Patrycja Suchorska-Woźniak,
  • Marta Fiedot and
  • Helena Teterycz

Beilstein J. Nanotechnol. 2014, 5, 2192–2201, doi:10.3762/bjnano.5.228

Graphical Abstract
  • concentration was changed, while the amount of other components was held constant. Characterisation of SnO2 nanoparticles UVvis spectroscopy: Spectroscopic studies were performed using an Evolution 201 UV–vis spectrophotometer from Thermo Scientific. The studies were performed at 23 °C in quartz cuvettes
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Published 20 Nov 2014
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