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

• (XRD), transmission electron microscopy (TEM) and laser-induced breakdown spectroscopy (LIBS) are applied to monitor the time-dependent development of gold nanoparticles for up to 40 hours. Some vegetative cells (VC) are filled with nanoparticles within minutes, while the extracellular polymeric

• observation of XRD and TEM that nanoparticle formation takes place in the first few hours after exposure to Au3+. As seen in Figure 6 the amount of gold is continuously increasing over the first two hours for Anabaena cylindrica. The time-dependent development seems to be the same for a ten times smaller

• . The time-dependent growth of nanoparticles and the distribution of their size were examined for the first time on a time scale of hours up to at least two days of incubation. TEM reveals a large variation between individual cells and most nanoparticles are found in vegetative cells and not in the

A simple and efficient quasi 3-dimensional viscoelastic model and software for simulation of tapping-mode atomic force microscopy

• Santiago D. Solares

Beilstein J. Nanotechnol. 2015, 6, 2233–2241, doi:10.3762/bjnano.6.229

• analytical models cannot reproduce stress relaxation and creep [10][11]. Within AFM, this means that when the tip and sample are held in contact at a fixed relative position, the model must exhibit a time-dependent reduction in the stress (stress relaxation). Additionally, when the tip and sample are held in

• contact at a fixed stress, the model must exhibit a time-dependent relaxation of the position of the sample directly under the tip. That is, the sample must yield, allowing the tip to gradually increase the depth of indentation. Furthermore, if the tip is quickly removed following yielding of the surface

Magnetic reversal dynamics of a quantum system on a picosecond timescale

• Nikolay V. Klenov,
• Alexey V. Kuznetsov,
• Igor I. Soloviev,
• Sergey V. Bakurskiy and
• Olga V. Tikhonova

Beilstein J. Nanotechnol. 2015, 6, 1946–1956, doi:10.3762/bjnano.6.199

• the stationary states and , respectively, and the time-dependent probability amplitudes of the eigenstates a(t) and b(t) obey the condition |a(t)|2 + |b(t)|2 = 1. We suppose (see Figure 1) that at t = tin an external magnetic field, H(t), directed along the OX axis, starts to act on the system and

• (when ωl = 0) became critical in recent years in connection with the possibility to create magnetic field pulses of picosecond duration [16]. The time-dependent field is then given by: In matrix notation the problem looks quite simple: where . In the general case, this problem cannot be analytically

• solved due to the presence of the complex exponential function. We seek the approximate solution of Equation 10 in the form of the matrix exponential representation: where the matrix exponent can be understood as a sum where the time-dependent matrix A(t) obeys the differential equation . The solution

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

• is possible that a passivating effect from the alloyed gold is responsible for these observations. Future studies on the time-dependent dissolution of such alloyed nanoparticles in biological media may help to better understand this effect. Experimental Chemicals We used silver nitrate (Roth, p.a

Tunable magnetism on the lateral mesoscale by post-processing of Co/Pt heterostructures

• Oleksandr V. Dobrovolskiy,
• Maksym Kompaniiets,
• Roland Sachser,
• Fabrizio Porrati,
• Christian Gspan,
• Harald Plank and
• Michael Huth

Beilstein J. Nanotechnol. 2015, 6, 1082–1090, doi:10.3762/bjnano.6.109

• °C, and dropped to 70–90 μΩ·cm after 10 oxygen pulses. Figure 3 depicts the time-dependent normalized conductance of the Pt layer of sample C during the purification process. The post-processed Pt layers exhibited a nano-porous structure and a reduction of height from 50 ± 1.5 nm to 11 ± 1.5 nm, as

• in this work. Throughout the text the samples are referred to by their labels A, B, C, and D, as indicated. SEM images of the samples. The 500 × 860 nm2 insets show the morphology of the post-processed Co/Pt FEBID nano-stripes in the middle of the overlap of the nano-stripes. Time-dependent

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

• different discharge products decompose at different potentials during charging. The matrix certainly includes some simplifications: side reactions might be time dependent, the voltage profile can change during cycling, overpotential increases with current density, etc. However, the matrix allows for a

Effects of swift heavy ion irradiation on structural, optical and photocatalytic properties of ZnO–CuO nanocomposites prepared by carbothermal evaporation method

• Sini Kuriakose,
• D. K. Avasthi and
• Satyabrata Mohapatra

Beilstein J. Nanotechnol. 2015, 6, 928–937, doi:10.3762/bjnano.6.96

• estimating the band gap energies. Raman spectra from pristine and irradiated ZnO–CuO nanocomposite samples. Growth mechanism of ZnO nanorods and nanosheets in the nanocomposites. (a–e) UV–visible absorption spectra showing the sun-light-driven time-dependent photocatalytic degradation of MB dye through

• pristine and irradiated ZnO–CuO nanocomposite samples as photocatalysts. (f) Kinetics of the photocatalytic degradation of MB shown through time dependent variation of C/C0. (g) Repetitive tests using 3 × 1013 ions/cm2 irradiated sample for two runs of photocatalytic degradation studies on MB dye. (a–d) UV

• -visible absorption spectra showing sun light driven time dependent photocatalytic degradation of MO dye using the pristine and irradiated ZnO-CuO nanocomposite samples as photocatalysts. (e) Kinetics of photocatalytic degradation of MO dye shown through time dependent variation of C/C0. (f) Repetitive

Electron-stimulated purification of platinum nanostructures grown via focused electron beam induced deposition

• Brett B. Lewis,
• Michael G. Stanford,
• Jason D. Fowlkes,
• Kevin Lester,
• Harald Plank and
• Philip D. Rack

Beilstein J. Nanotechnol. 2015, 6, 907–918, doi:10.3762/bjnano.6.94

• -deposition electron exposure treatment in a localized oxygen ambient at room temperature. Time-dependent studies demonstrate that the process occurs from the top–down. Electron beam energy and current studies demonstrate that the process is controlled by a confluence of the electron energy loss and oxygen

Protein corona – from molecular adsorption to physiological complexity

• Lennart Treuel,
• Dominic Docter,
• Michael Maskos and
• Roland H. Stauber

Beilstein J. Nanotechnol. 2015, 6, 857–873, doi:10.3762/bjnano.6.88

• compositional changes has been shaped by Vroman in 1962 [164] who described the time-dependent composition of a protein layer. This description is commonly referred to as “Vroman effect” and it suggests that the bound protein layer is dominated by highly abundant proteins at short exposure times which are later

• all consisting of HSA with just minor chemical modifications as described above. Internalization of HSAam-coated NPs by the cells was completely suppressed within the sensitivity limits of their experiment. In addition the time-dependent NP uptake by HeLa cells was investigated, using spinning disk

Production, detection, storage and release of spin currents

• Michele Cini

Beilstein J. Nanotechnol. 2015, 6, 736–743, doi:10.3762/bjnano.6.75

• the connection is not symmetric. Moreover, properly connected rings can be used to pump currents in the wires giving raise to a number of interesting new phenomena. At half filling using a time-dependent magnetic field in the plane of the ring one can pump a pure spin current, excited by the the spin

• driven by a time-dependent magnetic field. Geometry and dynamics of spin current generation In this Section, I recall the Hamiltonian Hprod, the same as in [12], which, in the half filling case, describes the magnetic production of the spin current based on a quantum pumping effect in the absence of an

• on spin and is: with the Bohr magneton μB = 5.79375 · 10−5 eV/T. The time-dependent field lies in the plane of the ring and has no flux through it. However, it couples to the electron spins in the ring, where the magnetic spin-flip combined with the spin–orbit interaction excites the spin current

Entropy effects in the collective dynamic behavior of alkyl monolayers tethered to Si(111)

• Christian Godet

Beilstein J. Nanotechnol. 2015, 6, 583–594, doi:10.3762/bjnano.6.60

• ] and measurements can be performed in a well-defined metal/OML/semiconductor planar configuration, which is relevant for molecular electronics devices. Admittance spectroscopy provides insights in the modulation of localized charge density and dipole reorientation in a system submitted to a time

• -dependent electric field. Dissipation (energy loss) mechanisms can be described by using equivalent representations of the complex admittance, including the dielectric permittivity ε* and electrical modulus M*. Dipole reorientation requires an activation of the system with energy barriers related either to

Dynamic force microscopy simulator (dForce): A tool for planning and understanding tapping and bimodal AFM experiments

• Horacio V. Guzman,
• Pablo D. Garcia and
• Ricardo Garcia

Beilstein J. Nanotechnol. 2015, 6, 369–379, doi:10.3762/bjnano.6.36

• the time-dependent, vertical displacement of the differential beam’s element placed at the x position. To numerically solve the above equation, we replace it by a system of point-mass equations, one for each relevant mode, n = 1, 2, etc. as described by [16][44][45] with m = 0.25·mc and 1 + cos (κn

• Paulo [51] combines the relationship between the stress and strain given by the Kelvin–Voigt model and the sample deformation given by Hertz contact mechanics as where η is the viscosity coefficient. Standard linear solid viscoelastic model (SLS) The SLS model is considered to represent the time

• -dependent behavior of a viscoelastic material without residual strains [52]. The model characterizes a viscoelastic material as an elastic element, which is coupled in series with a system that includes another elastic element and a viscous response. The equivalent mechanical system is a spring in series

Comparative evaluation of the impact on endothelial cells induced by different nanoparticle structures and functionalization

• Lisa Landgraf,
• Ines Müller,
• Peter Ernst,
• Miriam Schäfer,
• Christina Rosman,
• Isabel Schick,
• Oskar Köhler,
• Hartmut Oehring,
• Vladimir V. Breus,
• Thomas Basché,
• Carsten Sönnichsen,
• Wolfgang Tremel and
• Ingrid Hilger

Beilstein J. Nanotechnol. 2015, 6, 300–312, doi:10.3762/bjnano.6.28

• MnO and Fe3O4, again, those with an elongated shape (Au@MnO and Au@Fe3O4, Figure 1b and Figure 1c) led to a stronger reduction of ATP levels than the spherical ones in a time-dependent manner. In general, the MnO-based nanoparticles and nanoparticles with NH2-functionalization had a stronger impact on

Overview about the localization of nanoparticles in tissue and cellular context by different imaging techniques

• Anja Ostrowski,
• Daniel Nordmeyer,
• Alexander Boreham,
• Cornelia Holzhausen,
• Lars Mundhenk,
• Christina Graf,
• Martina C. Meinke,
• Annika Vogt,
• Sabrina Hadam,
• Jürgen Lademann,
• Eckart Rühl,
• Ulrike Alexiev and
• Achim D. Gruber

Beilstein J. Nanotechnol. 2015, 6, 263–280, doi:10.3762/bjnano.6.25

• surface functionalization and binding of other molecules of interest may remain completely similar to that of unlabeled particles [79][83][84]. Another disadvantage when using fluorescent dyes is their time-dependent photobleaching, which results in a more or less rapid fading of the fluorescent yield [85

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

• with the free drug (LD) in a dose- and time-dependent manner at concentrations of 0 μg mL−1 (control) to 50 μg mL−1. The LD compound demonstrates a sustained decrease in cell viability with increasing concentration at each time point. This observation is comparable with the results published by

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

• migration, proliferation and tissue formation [19][20]. Mechanical behavior of living cells can be monitored spatially resolved in a concentration and time dependent manner using scanning probe techniques. It is possible to investigate local cellular elastic properties under physiological conditions using

Kelvin probe force microscopy in liquid using electrochemical force microscopy

• Liam Collins,
• Stephen Jesse,
• Jason I. Kilpatrick,
• Alexander Tselev,
• M. Baris Okatan,
• Sergei V. Kalinin and
• Brian J. Rodriguez

Beilstein J. Nanotechnol. 2015, 6, 201–214, doi:10.3762/bjnano.6.19

• electrostatic measurements in both ionically-active and -inactive liquids. EcFM is employed to detect the bias- and time-dependent electrostatic and electrochemical forces between probe and sample under ambient, non-polar (ionically-inactive decane) and polar (ionically-active isopropanol, milli-Q water and

• aqueous NaCl) environments. The measurement of bias- and time-dependent ion dynamics allows different electrokinetic phenomena to be separated and a set of environmental and measurement timescale requirements for determining CPD under conditions comparable with KPFM to be delineated. Finally, the

• electrostatic response, or more generally when the force experienced by the system is governed purely by the time-independent Maxwell stress tensor directly related to the charge density between probe and sample [58]. The data can be presented as an EcFM spectra representing the bias- and time-dependent for a

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

• mouse kidney fibroblast showed very low adhesion to collagen I and laminin 332, but high adhesion to fibronectin. This indicates that cell lines express different patterns of CAMs. Besides the cell line-dependent adhesion forces, contact time-dependent strengthening also differed between cell lines

Functionalization of α-synuclein fibrils

• Simona Povilonienė,
• Vida Časaitė,
• Virginijus Bukauskas,
• Arūnas Šetkus,
• Juozas Staniulis and
• Rolandas Meškys

Beilstein J. Nanotechnol. 2015, 6, 124–133, doi:10.3762/bjnano.6.12

• attachment of gold nanoparticles to fibrils formed by α-SynC141 (Figure 3). The assembly process was found to be time dependent. After 24 hours of incubation, neutravidin-conjugated nanoparticles were found evenly scattered among the biotinylated fibrils. A number of fibrils involved in the nanoladder

Manganese oxide phases and morphologies: A study on calcination temperature and atmospheric dependence

• Matthias Augustin,
• Daniela Fenske,
• Ingo Bardenhagen,
• Anne Westphal,
• Martin Knipper,
• Thorsten Plaggenborg,
• Joanna Kolny-Olesiak and
• Jürgen Parisi

Beilstein J. Nanotechnol. 2015, 6, 47–59, doi:10.3762/bjnano.6.6

• different nanostructured MnOx species via one calcination process. This is advantageous for the investigation of the properties of the manganese oxides, as it rules out any synthesis-caused effects. The temperature- as well as the time-dependent phase transformation processes occurring during the oxidation

• at ν = 50 mV/s. Supporting Information The supporting information features the powder XRD pattern of Mn(II) glycolate particles after 1 h of synthesis at 170 °C in addition to in situ XRD patterns of the time-dependent oxidation of Mn3O4 to Mn5O8 at 400 °C in O2. Supporting Information File 14

Mammalian cell growth on gold nanoparticle-decorated substrates is influenced by the nanoparticle coating

• Christina Rosman,
• Sebastien Pierrat,
• Marco Tarantola,
• David Schneider,
• Eva Sunnick,
• Andreas Janshoff and
• Carsten Sönnichsen

Beilstein J. Nanotechnol. 2014, 5, 2479–2488, doi:10.3762/bjnano.5.257

• regime from 10−0.5 to 10−1.5 Hz, as described by Giaever et al. [29], which corresponds to slopes ranging from −2.1 to −3 s−1 for fully motile epithelial cells exhibiting 100% micromotion and 0 to −1 for bare electrodes as well as fixed cells immersed in buffer. The time-dependent slopes were recorded

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

• selective excitation of the focal volume [93][94]. Nevertheless, it remains challenging to extend the technique to time-dependent measurements for clinically relevant volumes, reaching beyond small animals used as testing systems at the moment [95][96][97][98]. Surface modification of Janus particles The

Modeling viscoelasticity through spring–dashpot models in intermittent-contact atomic force microscopy

• Enrique A. López-Guerra and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2014, 5, 2149–2163, doi:10.3762/bjnano.5.224

• characterization with AFM. Results and Discussion Model descriptions Linear Maxwell model The Linear Maxwell model is one of the simplest spring–dashpot sets. It consists of a spring arranged in series with a dashpot (Figure 1a). This model is known for successfully describing stress relaxation (time-dependent

• drop in stress under a constant strain) and for failing to describe creep (time-dependent strain relaxation under a constant stress). The latter precludes the existence of a mechanism for surface recovery upon deformation. As a consequence, the sample continuously yields to lower positions when

• capture both stress relaxation and creep compliance, which are basic time-dependent properties exhibited by viscoelastic surfaces. It is comprised by a Linear Maxwell arm arranged in parallel with a spring (Figure 3a) and has been recently used in the context of multifrequency and spectral inversion AFM

Dissipation signals due to lateral tip oscillations in FM-AFM

• Michael Klocke and
• Dietrich E. Wolf

Beilstein J. Nanotechnol. 2014, 5, 2048–2057, doi:10.3762/bjnano.5.213

• solvable. As a first step, the x-dependence of the z-component of the force is neglected by approximating Fz(x, z) ≈ Fz(x0, z). Then the solution z(t) of Equation 1 is independent of Equation 2. This leads to an effectively time-dependent lateral force Fx(x, z(t)) for Equation 2. As the interaction between

Imaging the intracellular degradation of biodegradable polymer nanoparticles

• Anne-Kathrin Barthel,
• Martin Dass,
• Melanie Dröge,
• Jens-Michael Cramer,
• Daniela Baumann,
• Markus Urban,
• Katharina Landfester,
• Volker Mailänder and
• Ingo Lieberwirth

Beilstein J. Nanotechnol. 2014, 5, 1905–1917, doi:10.3762/bjnano.5.201

• distribution of PLLA nanoparticle diameters as determined from 164 individual particles after HPF processing and TEM examination. Time-dependent UV–vis adsorption measurement monitoring the formation of the FeCl(H2O)52+ complex upon addition of HCl to pristine magnetite particles and magnetite-decorated PLLA