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Search for "thermal" in Full Text gives 1215 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.
Humidity-dependent electrical performance of CuO nanowire networks studied by electrochemical impedance spectroscopy
Beilstein J. Nanotechnol. 2023, 14, 683–691, doi:10.3762/bjnano.14.54
- electrode interconnects for nanoelectronics. Specifically, they can be used to transduce electric signals in nanoelectromechanical system (NEMS) switches [5], which concerns the development of nanoelectronics capable to operate in harsh environments [17]. Additionally, the excellent thermal stability of CuO
- nanowires are synthesized by thermal oxidation [9] and aligned between metallic microelectrodes by DEP [26]. Electrical properties of the nanowire-based system at various RH values are assessed by EIS [27][28]. To attempt a systematic study on the suitability of the CuO nanowire networks for different
- nanowires synthesized by thermal annealing of copper are a p-type semiconductor material [9][12][14]; its majority charge carriers are positive holes (h+) related to the presence of Cu vacancies or impurities. Under dry conditions, possible ionosorption of oxygen species from air on the nanowire surface
Metal-organic framework-based nanomaterials as opto-electrochemical sensors for the detection of antibiotics and hormones: A review
Beilstein J. Nanotechnol. 2023, 14, 631–673, doi:10.3762/bjnano.14.52
- of their exceptionally high thermal and electrical conductivities, effective catalytic properties, high chemical stability, rapid rate of electron transfer, adequate surface area, and favourable piezoelectric, electronic and gravimetric properties, metal and metal oxide materials with sizes less than
- extremely low densities (0.1–1 g·cm−3), the highest specific surface areas (165–7800 m2·g−1) currently known, tunable surface properties, good mechanical and thermal stability, intriguing and controllable morphologies, and uniform yet tunable pores that are created by the self-assembly of metal ions or
Titania nanoparticles for photocatalytic degradation of ethanol under simulated solar light
Beilstein J. Nanotechnol. 2023, 14, 616–630, doi:10.3762/bjnano.14.51
- with high purity, which did not require thermal treatment after synthesis (ca. 1 atom % of impurities). These nanoparticles show an increased anatase phase content (77.33–87.42%) and crystallite sizes of 23–45 nm. The TEM images showed that in both series small crystallites form spheroidal
- AM 1.5 solar light (1000 W/m2) was provided by a Peccell L01 solar simulator. For each test, 200 µL gas samples were taken from the photoreactor every 30 min and analyzed with two gas chromatographs equipped with either a flame ionization detector (FID, Agilent 7890A) or a thermal conductivity
Thermal transport in kinked nanowires through simulation
Beilstein J. Nanotechnol. 2023, 14, 586–602, doi:10.3762/bjnano.14.49
- Alexander N. Robillard Graham W. Gibson Ralf Meyer Bharti School of Engineering and Computer Science, Laurentian University, Sudbury P3E 2C6, Canada 10.3762/bjnano.14.49 Abstract The thermal conductance of nanowires is an oft-explored quantity, but its dependence on the nanowire shape is not
- completely understood. The behaviour of the conductance is examined as kinks of varying angular intensity are included into nanowires. The effects on thermal transport are evaluated through molecular dynamics simulations, phonon Monte Carlo simulations and classical solutions of the Fourier equation. A
- Fourier model. Keywords: ballistic transport; kinked nanowire; molecular dynamics; phonon Monte Carlo; thermal transport; Introduction The thermal conductivity of semiconductor nanostructures is of great interest because of potential applications in a wide variety of fields, such as thermal control
Carbon nanotube-cellulose ink for rapid solvent identification
Beilstein J. Nanotechnol. 2023, 14, 535–543, doi:10.3762/bjnano.14.44
- has resurfaced recently as a smart material because of its excellent thermal-mechanical properties, biocompatibility, biodegradability, and flexibility [22][23][30][31]. Composites based on carbon nanotubes or graphene and cellulose have been reported for, among other things, humidity and vapor
- , our results demonstrate that the dielectric constant plays an essential role in the sensing mechanism with a clear correlation with the maximum gain of the sensor. Also, the width of the curves seems to be strongly influenced by the thermal properties of the liquids. As shown in Figure 4c, the vapor
- pressure of the solvents controls the time the liquid will stay within the sensor before it evaporates. This makes it a key factor regarding the swelling process of the CPC matrix and the electron tunneling process. To investigate this hypothesis, we designed an experiment to mimic the thermal effects
On the use of Raman spectroscopy to characterize mass-produced graphene nanoplatelets
Beilstein J. Nanotechnol. 2023, 14, 509–521, doi:10.3762/bjnano.14.42
- materials [5], offering an array of products with a wide range of properties such as improved mechanical strength and higher thermal conductivity. To accelerate the further development and adoption of GR2Ms, it is critical to develop reliable and standardized methods to characterize the materials being
Specific absorption rate of randomly oriented magnetic nanoparticles in a static magnetic field
Beilstein J. Nanotechnol. 2023, 14, 485–493, doi:10.3762/bjnano.14.39
- magnetic field, denoted by the symbol h. It is assumed that at the initial moment of time, the unit magnetization vector of the particle is given by αx = 1. Irregular perturbations of the components of the unit magnetization vector occur due to thermal fluctuations of the particle magnetic moment at T
- ] that optimized assemblies of magnetic nanoparticles are promising for the use in magnetic hyperthermia. However, it is necessary to strictly control the spatial distribution of magnetic nanoparticles in the tumor in order to exclude undesirable thermal effects on healthy tissues surrounding the tumor
- [30]. The combination of MH and MPI techniques seems promising, as it will allow one to localize the heat release in the tumor-affected organ more accurately and to minimize the thermal effect on healthy tissues, which may also contain a certain amount of magnetic nanoparticles. Obviously, to
A mid-infrared focusing grating coupler with a single circular arc element based on germanium on silicon
Beilstein J. Nanotechnol. 2023, 14, 478–484, doi:10.3762/bjnano.14.38
- (GOSI) [7], germanium on insulating substrate (GOI) [8][9], and germanium on silicon nitride substrate (GOSN) [10]. Among them, Ge-on-Si platforms have been widely applied in on-chip sensors, nonlinear optics, free space communication, and thermal imaging [1][6] because portable, cost-effective, and
Conjugated photothermal materials and structure design for solar steam generation
Beilstein J. Nanotechnol. 2023, 14, 454–466, doi:10.3762/bjnano.14.36
- absorbers based on (1) various molecular designs of small molecules and polymers, (2) absorber structures from a thermal management perspective, and (3) applications to desalination, sterilization, wastewater treatment, and power generation. As we focus on the SSG application in this review, the other
- of the steam generation from heat. The generated thermal energy must be used for water evaporation and heat loss to the environment needs to be avoided. Sunlight absorption The wavelength range and intensity of the solar spectrum are important factors for harnessing solar energy. As this review
- from 300 to 2500 nm and reflectance, transmission, and radiative relaxation must not be significant in order to maximize the energy absorbed from the sun and convert it into thermal energy (Figure 2b). Photothermal conversion efficiency Solar energy can be converted into various forms of energy such as
Molecular nanoarchitectonics: unification of nanotechnology and molecular/materials science
Beilstein J. Nanotechnol. 2023, 14, 434–453, doi:10.3762/bjnano.14.35
- non-negligible effect. For example, thermal fluctuations, stochastic distributions, and quantum effects affect nanoscale phenomena. Therefore, when building materials from nanoscale units, these uncertainties are included to harmonize the various effects [55][56]. Recent publications advocating
- both metallic and semiconducting properties. These networks have been applied to thermoelectric materials and have been found to exhibit low interplane thermal conductivity, which is not typical of carbon materials, while maintaining the interplane electrical conductivity. Müllen, Fuchs, Chi, and co
Plasmonic nanotechnology for photothermal applications – an evaluation
Beilstein J. Nanotechnol. 2023, 14, 380–419, doi:10.3762/bjnano.14.33
- tunability of optothermal properties and enhanced stability, these nanostructures show a wide range of applications in optical sensors, steam generation, water desalination, thermal energy storage, and biomedical applications such as photothermal (PT) therapy. The PT effect, that is, the conversion of
- nanocomposites. A detailed investigation of the essential, but often ignored, concept of thermal, chemical, and aggregation stability of nanoparticles is another part of this review. The challenges that remain, as well as prospective directions and chemistries, regarding nanomaterials for PT conversion are
- cause little damage to adjacent healthy tissues due to extremely localized heating [3]. Generally, the reduction of material dimensions to the nanoscale, such as in graphene, carbon nanotubes (CNT) and polymers, leads to an enhancement of the PT effect due to factors such as improved thermal
Polymer nanoparticles from low-energy nanoemulsions for biomedical applications
Beilstein J. Nanotechnol. 2023, 14, 339–350, doi:10.3762/bjnano.14.29
- component addition or on the thermal history. Nanoemulsions are not to be confused with microemulsions, which are equilibrium systems with thermodynamic stability [4]. Because of their very small drop size, the main mechanism for nanoemulsion destabilization is commonly attributed to Ostwald ripening
Bismuth-based nanostructured photocatalysts for the remediation of antibiotics and organic dyes
Beilstein J. Nanotechnol. 2023, 14, 291–321, doi:10.3762/bjnano.14.26
- is a small (6-coordinate, such as Ti, W, Mo, or Fe) cation. It is another visible-light-driven n-type bismuth-based semiconductor and has received a lot of attention because of its distinctive layered structure, eco-friendliness, high photochemical and thermal stability, and benign visible-light
- layer of the structure more quickly than those in a 3-D structure. It is important to note that an effective photocatalyst should have the following properties: (a) strong absorption both of UV and visible light (i.e., a suitable bandgap value, usually less than 3.0 eV); (b) thermal, chemical, and
- account are the quantity and type of dopant. The photocatalytic performance may be impacted if the amount of dopant is greater than the optimum value because it may act as a recombination site for photoinduced charge carriers. Additionally, doping has some drawbacks such as thermal instability and carrier
Recent progress in cancer cell membrane-based nanoparticles for biomedical applications
Beilstein J. Nanotechnol. 2023, 14, 262–279, doi:10.3762/bjnano.14.24
- ]. The precisely targeted thermal killing of tumor tissue can help to improve the efficiency of energy utilization and reduce power and time during ablation, which will minimize damage to normal tissue around the tumor [95]. Photothermal therapy (PTT) can generate thermal energy by using near-infrared
- oxidation, improve biocompatibility, enhance colloidal stability, and enhance targeting), enabling the ablation of tumor tissues by thermal energy [79]. MDA-MB-231 cell membrane-coated NPs loaded with superparamagnetic iron oxide nanoparticles (SPIONs) and PTX were designed for the combination treatment of
- [111]. After absorbing energy, the ultrasound sensitizer exerts antitumor efficacy through various pathways, such as ROS generation, mechanical effects, thermal effects, and immune system-oriented efficacy [111][112]. Based on the diverse functions of SDT, Luo et al. synthesized porphyrin-based metal
Spin dynamics in superconductor/ferromagnetic insulator hybrid structures with precessing magnetization
Beilstein J. Nanotechnol. 2023, 14, 233–239, doi:10.3762/bjnano.14.22
- spin current takes the following form [29]: where K is the Keldysh component. Using the normalization condition, Keldysh Green’s function can be written through the distribution function : . In thermal equilibrium, the distribution matrix reduces to a function tanh(βℏω/2), β = 1/kT, which corresponds
- induced magnetization [35]. However, more precise results presented in Figure 3 show that the induced magnetization at the interface depends nonmonotonically on the precession frequency. Moreover, a maximum becomes obvious with increasing temperature, even if we do not take into account the thermal
Cyclodextrins as eminent constituents in nanoarchitectonics for drug delivery systems
Beilstein J. Nanotechnol. 2023, 14, 218–232, doi:10.3762/bjnano.14.21
- smaller band overlap of the trans/cis isomers, and thus the photoisomerization proceeds almost completely in both directions. Moreover, thermal relaxation of the cis isomer is negligible [52]. Like azobenzenes, only the trans isomer forms inclusion complexes with CyDs. In Figure 3b, carboxymethyl
- nanoarchitectures to promote photothermal therapy In photothermal therapy, light energy is converted to thermal energy, which ultimately kills malignant cells [86]. In general, tumors are less resistant to heat than normal tissues. Advantageously, even light of long wavelengths is directly employable. Furthermore
Concentration-dependent photothermal conversion efficiency of gold nanoparticles under near-infrared laser and broadband irradiation
Beilstein J. Nanotechnol. 2023, 14, 205–217, doi:10.3762/bjnano.14.20
- temperature decay profile of the suspension after the light source is turned off. At thermal equilibrium, the temporal change in the temperature becomes almost zero. Hence, the photothermal conversion efficiency can be described as: By using Equation 6 and Equation 7, the temperature rise of a GNP suspension
- concentrations. Under NIR laser irradiation, the photothermal conversion efficiency increases with an increase in optical power. The reported maximum temperature increase of 16 °C corresponds to about 53 °C with respect to the physiological temperature of 37 °C, which is sufficient for thermal threatment of
A novel approach to pulsed laser deposition of platinum catalyst on carbon particles for use in polymer electrolyte membrane fuel cells
Beilstein J. Nanotechnol. 2023, 14, 190–204, doi:10.3762/bjnano.14.19
- (absolute) pressure in an argon atmosphere. After thermal ignition, a mixture of magnesium and calcium formate powders (mixed with a 6:1 molar ratio) reacted vigorously in a self-propagating high-temperature regime, giving rise to MgO/CaO and carbon as the main solid-state products. After the reaction, a
High–low Kelvin probe force spectroscopy for measuring the interface state density
Beilstein J. Nanotechnol. 2023, 14, 175–189, doi:10.3762/bjnano.14.18
- electron and hole densities of the bulk state. Analogously, the emission rates per unit volume for electrons and holes ( and ) are given by In thermal equilibrium, the amount of capture and the amount of emission for a carrier coincide as follows: The net generation/recombination rate RSRH is given by the
- τp in n-type semiconductors and the electron (minority carrier) lifetime τn in p-type semiconductors as follows: where σn and σp are the capture cross sections for electrons and holes, respectively, vth is the thermal velocity, and Nit is the concentration of interface states. These equations
- indicate that the carrier lifetimes τp and τn are reciprocals of the capture rates per single carrier determined by the capture cross sections σn and σp, thermal velocity vth, and concentration of interface states Nit, which depend on semiconductor type, temperature, carrier density, and interface state
Formation of nanoflowers: Au and Ni silicide cores surrounded by SiOx branches
Beilstein J. Nanotechnol. 2023, 14, 133–140, doi:10.3762/bjnano.14.14
- always deposited after the Ni layer to prevent the oxidation of the Ni layer. The bilayer thicknesses of different systems were 15 nm Au/5 nm Ni, 10 nm Au/10 nm Ni and 5 nm Au/15 nm Ni, and the thickness of each layer was controlled by a quartz balance during the deposition. Thermal annealing was carried
- out in a rapid thermal processing (RTP, Jipelec Jetstar 100) furnace. First, the chamber was evacuated and purged with Ar three times at room temperature, then a flow of forming gas of Ar + H2 (volume ratio 30:1) was kept till the end of the experiment. The temperature was ramped up to 300 °C in 20 s
Intermodal coupling spectroscopy of mechanical modes in microcantilevers
Beilstein J. Nanotechnol. 2023, 14, 123–132, doi:10.3762/bjnano.14.13
- , these improvements have yet to find a practical way to AFM. As a solution, we investigate here a mechanism in which individual mechanical eigenmodes of a microcantilever couple to one another, mimicking optomechanical techniques to reduce thermal noise. We have a look at the most commonly used modes in
- , which would activate intermodal coupling between two or more eigenmodes. With this geometric nonlinearity, we can circumvent the use of tip–sample forces and apply techniques from optomechanics. Sideband cooling will reduce thermal noise of the fundamental mode. Parametric amplification relies on
- and mode splitting. Applying the sum, referred to as blue sideband pump, will cause either mode squeezing or parametric amplification [22], provided that the amplitude is optimally chosen. We will focus on the red sideband, as sideband cooling is useful for reducing thermal noise in standard AFM and
Characterisation of a micrometer-scale active plasmonic element by means of complementary computational and experimental methods
Beilstein J. Nanotechnol. 2023, 14, 110–122, doi:10.3762/bjnano.14.12
- optical and thermal data are used to inform detailed finite element method simulations for verification and to predict system responses allowing for enhanced design choices to maximise modulation depth and localisation. Keywords: active plasmonics; atomic force microscope; scanning Joule expansion
- applications in the development of new imaging technologies using this localised field to go beyond the diffraction limit of light. Because the temperature is geometry-dependent in the constriction, it is necessary to map the thermal distribution in the vicinity of the element. The experimental complementary
- method therefore investigates the thermal response of this active plasmonic element at a high spatial resolution. Knowledge of the distribution leads to predictions on how the near field will be locally affected, which is key for understanding the behaviour of the active plasmonic element. The heating
Antimicrobial and mechanical properties of functionalized textile by nanoarchitectured photoinduced Ag@polymer coating
Beilstein J. Nanotechnol. 2023, 14, 95–109, doi:10.3762/bjnano.14.11
- difficult to implement and tend to cause NP self-aggregation. In situ methods are therefore generally preferred and typically require the polymer film surface to be treated with a metal precursor solution (layer-by-layer [37][38], sol–gel [39]) before undergoing thermal [40] or chemical reduction reactions
Gap-directed chemical lift-off lithographic nanoarchitectonics for arbitrary sub-micrometer patterning
Beilstein J. Nanotechnol. 2023, 14, 34–44, doi:10.3762/bjnano.14.4
- ) was obtained from the ELGA PURELAB classic system (Taipei, Taiwan). CLL operation processes and bioactive substrates preparation In a manner similar to a previous study [26], silicon substrates with 100 nm thick Au and 5 nm Cr adhesive layers were prepared by thermal evaporation. To prepare a SAM
The influence of structure and local structural defects on the magnetic properties of cobalt nanofilms
Beilstein J. Nanotechnol. 2023, 14, 23–33, doi:10.3762/bjnano.14.3
- materials [7][8], in which heat storage and accumulation occur due to phase transformations. The functioning of such storage media is based on energy fluctuations in the process of crystallization or melting of the media. In contrast to traditional media, thermal storage does not require sealing of the
- . The normal and spin temperatures were maintained at the initial value of 5 K. The coordinates of the atoms changed insignificantly, which is associated with small thermal fluctuations and their linear velocities. As for the spin rearrangement, at the initial times, corresponding to the interval of 0–5
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