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Search for "threshold" in Full Text gives 399 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.
A new photodetector structure based on graphene nanomeshes: an ab initio study
Beilstein J. Nanotechnol. 2020, 11, 1036–1044, doi:10.3762/bjnano.11.88
- curves of A4Z6-6 and A4Z6-24 GNMs in comparison with a graphene device. The devices made from GNMs exhibit different transport characteristics than GNR and graphene devices. They have threshold voltage and behave like a diode at positive voltages. These effects are attributed to the formation of a
Microwave photon detection by an Al Josephson junction
Beilstein J. Nanotechnol. 2020, 11, 960–965, doi:10.3762/bjnano.11.80
- value calculated from the gap, is experimentally investigated for application as a threshold detector for microwave photons. We present the preliminary results of measurements of the lifetime of the superconducting state and the probability of switching by a 9 GHz external signal. We found an
- significant improvement of the noise immunity of a device, radically decreasing the dark count rate, but it will also decrease the single-photon sensitivity of the considered threshold detector. Quantization of the switching probability tilt as a function of the signal attenuation for various bias currents
- ]. For the lower-frequency range, a new class of single-microwave-photon detectors is needed. With regard to this, a current-biased Josephson junction (JJ) is of particular interest for applications as a threshold detector since its phase dynamics is altered even by a weak probe field. Rich dynamics of
Comparison of fresh and aged lithium iron phosphate cathodes using a tailored electrochemical strain microscopy technique
Beilstein J. Nanotechnol. 2020, 11, 583–596, doi:10.3762/bjnano.11.46
- 8. Figure 7 shows the same sample location as in Figure 5, but Figure 7b and 7e now present relaxation times after a positive dc-voltage pulse and Figure 7c and 7f after the negative dc-voltage pulse. We excluded data points below a certain threshold, since a minimal ESM signal intensity is needed
High dynamic resistance elements based on a Josephson junction array
Beilstein J. Nanotechnol. 2020, 11, 417–420, doi:10.3762/bjnano.11.32
- here the finite electric current is maintained by correlated Cooper pair tunneling at a voltage bias V across the QPSJ exceeding the particular Coulomb blockade threshold, VC [14]. The tunneling happens at the Bloch oscillation rate, fB. The synchronization of this “internal” periodic process with the
Using gold nanoparticles to detect single-nucleotide polymorphisms: toward liquid biopsy
Beilstein J. Nanotechnol. 2020, 11, 263–284, doi:10.3762/bjnano.11.20
- and ligases. Another advantage of using enzymes is their capability to sustain catalytic cycles, thus amplifying the number of available oligonucleotide sequences, which after reaching a concentration threshold induce the aggregation of nanoparticles. Therefore, a relatively low concentration of
- enzymes is required (1 U/µL) to maintain cyclic reactions and amplify the concentration of the DNA strands. However, the time required to reach the concentration threshold of a given strand is relatively long (hours), slowing down the operation of an assay. An additional drawback is that enzymatic
Rational design of block copolymer self-assemblies in photodynamic therapy
Beilstein J. Nanotechnol. 2020, 11, 180–212, doi:10.3762/bjnano.11.15
- for kinetically frozen vectors, which is very often the case for polymeric self-assemblies. Thus, for polymeric self-assemblies, we cannot talk anymore of critical micelle concentration (cmc) but only of critical aggregation concentration (cac) as the threshold for which their formation is observed. A
Size effects of graphene nanoplatelets on the properties of high-density polyethylene nanocomposites: morphological, thermal, electrical, and mechanical characterization
Beilstein J. Nanotechnol. 2020, 11, 167–179, doi:10.3762/bjnano.11.14
- thermal and electrical conductivities and the lowest electrical percolation threshold were achieved with GnPs of a larger lateral size. This could have been attributed to the fact that the GnPs of larger lateral size exhibited a better dispersion in HDPE and formed conductive pathways easily observable in
- percolation threshold than thicker ones. On the other hand, in terms of thermal conductivity, a remarkable amount of enhancement was observed only above a certain filler concentration. The results demonstrate that GnPs with smaller lateral size and larger thickness lead to lower enhancement of the samples
- demonstrated the same linear behavior as pure HDPE for all GnP concentrations. A similar behavior was also exhibited by the HDPE/G2 and HDPE/G3 nanocomposites below a certain concentration, called the percolation threshold, which is defined as the minimum filler concentration where the insulating material is
Internalization mechanisms of cell-penetrating peptides
Beilstein J. Nanotechnol. 2020, 11, 101–123, doi:10.3762/bjnano.11.10
- model was later proven experimentally in osteosarcoma and human smooth muscle cells [48]. According to the proposed model, when a concentration threshold is achieved on one of the membrane leaflets, the TAT peptides are attracted to the phosphate groups on the other leaflet. The peptides act
- drives the clustering of all cargo molecules to one region of the membrane, where the clathrin-coated vesicle will be formed. Oftentimes this point in CME has been referred to as “cargo checkpoint”, meaning that if a certain threshold of cargo molecules is not reached, the process of vesicle budding will
Nanosecond resistive switching in Ag/AgI/PtIr nanojunctions
Beilstein J. Nanotechnol. 2020, 11, 92–100, doi:10.3762/bjnano.11.9
- ]. Furthermore, since such rearrangements are subject to activated processes, the induced conductance changes are typically non-volatile at sub-threshold electric fields. As a consequence, networks of filamentary RRAM devices naturally lend themselves for the realization of physically unified platforms for all
- switching takes place when the magnitude of Vbias exceeds approx. 100 mV at either polarity. The minor deviation of the OFF and ON state I(V) branches from their zero-bias slopes (red and blue dashed lines, respectively) up to the switching threshold voltages is a hallmark of metallic conduction indicating
- threshold voltages, whereas the dynamical aspects of resistive switching comply to the voltage–time dilemma characteristic to various Ag-based filamentary resistive switches: A moderate linear increase in the magnitude of the driving voltage facilitates an exponential acceleration of the switching. The
Long-term stability and scale-up of noncovalently bound gold nanoparticle-siRNA suspensions
Beilstein J. Nanotechnol. 2019, 10, 2568–2578, doi:10.3762/bjnano.10.248
- in samples ×1 and ×10 was evaluated in each experimental point using the SPIP program (Image Metrology) using the digital images with a total area of 39.7 µm2 for each point. The number and diameter of all clusters were calculated using the particle and pore analysis module in advanced threshold
Mobility of charge carriers in self-assembled monolayers
Beilstein J. Nanotechnol. 2019, 10, 2449–2458, doi:10.3762/bjnano.10.235
- island with the particle analysis of the SPIP software (version 6.7.8) by setting the threshold current to 1 pA. (ii) Then – assuming a circular island shape – the island diameter d was computed from the area A using d = 2∙(A/π)1/2. (iii) Finally the center current of each island was plotted as a
Coating of upconversion nanoparticles with silica nanoshells of 5–250 nm thickness
Beilstein J. Nanotechnol. 2019, 10, 2410–2421, doi:10.3762/bjnano.10.231
- increases as the amount of TEOS increases, while core-free silica NPs appear when the TEOS content exceeds the threshold of homogeneous nucleation [36][39][47][48][49]. Typically, a maximum diameter <50 nm can be reached with this technique [23]. Microemulsion growth processes are usually slow and laborious
- formation of new micelles [23]. Ding et al. linked these considerations to the theory of LaMer [36]. According to the LaMer theory, heterogeneous nucleation occurs when the supersaturation of the growth species is below the homogeneous nucleation threshold but above the heterogeneous nucleation threshold
- , while a higher supersaturation (above the homogeneous nucleation threshold) leads to simultaneous heterogeneous and homogeneous nucleation. In general, the processes leading to homogeneous and heterogeneous nucleation and growth in such reverse microemulsion systems are complex and depend on numerous
Integration of sharp silicon nitride tips into high-speed SU8 cantilevers in a batch fabrication process
Beilstein J. Nanotechnol. 2019, 10, 2357–2363, doi:10.3762/bjnano.10.226
- results exclusively from the tip geometry, the noise suppression threshold is set at 100 pm which is superior to the measured image noise of 40 pm. Additionally, borders of the image are also excluded from the estimation to prevent edge artefacts. The inset of Figure 2a shows the result of the Gwyddion
Four self-made free surface electrospinning devices for high-throughput preparation of high-quality nanofibers
Beilstein J. Nanotechnol. 2019, 10, 2261–2274, doi:10.3762/bjnano.10.218
- maximal. The jet initiation in the OSFSE process viewed from the side by a high-speed camera is shown in Figure 4. Immediately after a voltage of 40 kV (which is above the threshold voltage) is applied to the solution surface, a deformation of the fluid is observed at the top edge of the solution
Use of data processing for rapid detection of the prostate-specific antigen biomarker using immunomagnetic sandwich-type sensors
Beilstein J. Nanotechnol. 2019, 10, 2171–2181, doi:10.3762/bjnano.10.210
- quantification with the immunosensor is lower than the threshold established for the serum level found in patients with prostate cancer (above 3.6 ng·mL−1 stage A1) [56]. The samples were diluted in PBS for reaching the linear range, providing a response within the stipulated standards for the samples. Using the
The importance of design in nanoarchitectonics: multifractality in MACE silicon nanowires
Beilstein J. Nanotechnol. 2019, 10, 2094–2102, doi:10.3762/bjnano.10.204
- and a NW length of 5 μm. For the other sample (labelled SiNW2; Figure 2b) the source substrate was As-doped with a doping density of about 1018 cm−3 and a NW length of 1.3 μm. Figure 3a and Figure 3b are the masked images obtained applying a height threshold on the AFM measurements of Figure 2. The
- threshold divides the surface into two regions: the tips of NWs (black colour) and the remainder of the sample (white colour). The NW tips appear clustered in both samples, creating a very complex architecture over the surfaces. It is noteworthy to observe that this clustering has not been purposefully
- have calculated the critical aspect ratio [31] of the NWs of samples SiNW1 and SiNW2. The critical aspect ratio is a threshold value for the stability of the bundles. NWs with aspect ratios larger than the critical one will remain attached after bending towards each other and getting in contact. Given
Review of advanced sensor devices employing nanoarchitectonics concepts
Beilstein J. Nanotechnol. 2019, 10, 2014–2030, doi:10.3762/bjnano.10.198
- sensors have a super-Nernstian sensitivity and reference-less nature. This organic charge-modulated field-effect transistor mechanism is attributed to the variation of the threshold voltage in the organic field-effect transistor induced by charge variation upon the presence of a charge (protonation, etc
- A induced the removal of the antibody from the sensor surface through competitive binding, resulting in a capacitance increase accompanied with an increase of the drain current. The switching-on signal response of this system is in the nM range of concentration threshold for bisphenol A detection
Gold-coated plant virus as computed tomography imaging contrast agent
Beilstein J. Nanotechnol. 2019, 10, 1983–1993, doi:10.3762/bjnano.10.195
- sample chamber with sterile syringes until the solution reached the tip of the nozzle. Ten 30 s videos using a camera level of 7 and a detection threshold of 5, were recorded for each sample and the software was used to estimate concentration and NP size. Measurements were recorded at ambient temperature
Processing nanoporous organic polymers in liquid amines
Beilstein J. Nanotechnol. 2019, 10, 1844–1850, doi:10.3762/bjnano.10.179
- structural variety of nanoporous polymers and amines. Properties of COP-100-Film Once COP-100-Film formed, it did not dissolve in any common organic solvents as long as the amount of EDA was within the threshold range, from 10 to 50 equiv of COP-100. The amount of nitrogen in COP-100-Film varied as the EDA
Growth dynamics and light scattering of gold nanoparticles in situ synthesized at high concentration in thin polymer films
Beilstein J. Nanotechnol. 2019, 10, 1768–1777, doi:10.3762/bjnano.10.172
- threshold method, nanoparticles can be isolated from the polymer matrix image and their shape/size characteristics can be determined (Figure 6). Similar morphological characteristics were also usually observed at a larger scale by optical microscopy and SEM [24]. Recently, the shape of the AuNPs was shown
- ). (A) PVA matrix with embedded in situ synthesized AuNPs (image size: 5 μm × 5 μm). (B) Details of the previous image (image size: 1 μm × 1 μm)). (C) Undoped PVA matrix (image size: 5 μm × 5 μm). Perimeter–area relationship of the AuNPs. Symbols: experimental data determined by using a height-threshold
Precise local control of liquid crystal pretilt on polymer layers by focused ion beam nanopatterning
Beilstein J. Nanotechnol. 2019, 10, 1691–1697, doi:10.3762/bjnano.10.164
- techniques such as patterning with nanogrooves [13][14][15] and nanoslits [16], ion-beam irradiation of specific inorganic [17] and polymer [18] substrates, subjecting of photo-controlled aligning polymers to near-threshold doses of ultraviolet radiation [19], formation of surface microdomains from
Nanoporous smartPearls for dermal application – Identification of optimal silica types and a scalable production process as prerequisites for marketed products
Beilstein J. Nanotechnol. 2019, 10, 1666–1678, doi:10.3762/bjnano.10.162
- rutin solution is used and evaporation continues, rutin continues to precipitate on the surface of completely loaded particles. When rutin deposits as a thin layer on the surface, the rutin stays amorphous; when the layer thickness increases above a critical threshold, crystallization occurs which can
Graphynes: an alternative lightweight solution for shock protection
Beilstein J. Nanotechnol. 2019, 10, 1588–1595, doi:10.3762/bjnano.10.154
- impact velocity values ranging from 1 to 6 km/s. It is found that to perforate the examined α-GY nanosheet, the velocity of the projectile should be larger than a threshold value of ca. 1.6 km/s. For impact velocity values lower than this threshold value, the projectile will be bounced back by the
- nanosheet. Similarly, the threshold velocity for β-GY, γ-GY and 6612-GY are 1.8 km/s, 1.8 km/s, and 1.6 km/s, respectively. Higher impact velocities will induce more severe local deformation, and there will be no time for the stress to develop a well distributed pattern as observed scenarios with in lower
Rapid thermal annealing for high-quality ITO thin films deposited by radio-frequency magnetron sputtering
Beilstein J. Nanotechnol. 2019, 10, 1511–1522, doi:10.3762/bjnano.10.149
- , the ITO films were subjected to RTA in air. This process was performed in an open resistive furnace (MILA 5000) in order to improve the structural and optical properties of the films. Thus, the samples were subjected to 575 °C at a heating rate of 20 °C/s and maintained at the thermal threshold for 10
Magnetic segregation effect in liquid crystals doped with carbon nanotubes
Beilstein J. Nanotechnol. 2019, 10, 1464–1474, doi:10.3762/bjnano.10.145
- the initial homogeneous planar texture of the liquid crystal–carbon nanotubes mixture is disturbed in a threshold manner (Fréedericksz transition). The orientational and concentration distributions of the suspension are studied for different values of the magnetic field strength and segregation
- anisotropy of the diamagnetic susceptibility, this leads to a decrease in the critical fields of magnetic [27][28] and electric [14][16][26][29][30] Fréedericksz transition (a threshold process of changing the orientational structure inside an NLC layer under the action of external fields [31]). Experiments
- , angular, and homeotropic phases [39]: The field hc in Equation 15 corresponds to the Fréedericksz transition field from the initial uniform planar phase to the nonuniform angular one. Equation 16 defines two threshold fields hr±, where hr+ corresponds to the transition from the angular phase to the
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