Heterogeneous reactions in a HFCVD reactor: simulation using a 2D model

• Xochitl Aleyda Morán Martínez,
• José Alberto Luna López,
• Zaira Jocelyn Hernández Simón,
• Gabriel Omar Mendoza Conde,
• José Álvaro David Hernández de Luz and
• Godofredo García Salgado

Beilstein J. Nanotechnol. 2024, 15, 1627–1638, doi:10.3762/bjnano.15.128

• ), (∇u)T is the transposed velocity gradient tensor, τ is the viscous stress tensor (Pa), μ is the dynamic viscosity (Pa·s), Q includes heat sources other than viscous dissipation (W·m−3), and δij is the Kronecker delta symbol. All equations in this section were taken from [26], except Equation 5, which

Investigation on drag reduction on rotating blade surfaces with microtextures

• Qinsong Zhu,
• Chen Zhang,
• Fuhang Yu and
• Yan Xu

Beilstein J. Nanotechnol. 2024, 15, 833–853, doi:10.3762/bjnano.15.70

• boundary layer theory as shown in Figure 6. The dimensionless size calculation formula of microtextures with drag reduction performance are as follows [32]: where μ is the dynamic viscosity, v is the kinematic viscosity, u is the average flow velocity, uτ is the wall stress shear rate, τw is the wall shear

Experimental investigation of usage of POE lubricants with Al₂O₃, graphene or CNT nanoparticles in a refrigeration compressor

• Kayhan Dağıdır and
• Kemal Bilen

Beilstein J. Nanotechnol. 2023, 14, 1041–1058, doi:10.3762/bjnano.14.86

• using pure oil. Moreover, density and dynamic viscosity of the nanolubricant samples used in the experiments were also measured, and their kinematic viscosity, which is an important parameter for lubricants, was calculated. It was determined that the kinematic viscosity continuously increased with

• viscosity, ν, was defined as the ratio of the dynamic viscosity to the density according to Equation 1. The density, ρ, of the nanolubricants was measured with the FPS2800 fluid property sensor. At the same time, the dynamic viscosity, µ, of the nanolubricants was measured using the FPS 2800 fluid property

• error analysis. The kinematic viscosity is calculated by Equation 1 with the help of the data obtained by measuring the density and dynamic viscosity values. Therefore, there is a need to determine the effect of uncertainties in the measured data of the calculated kinematic viscosity value. Thus, the

Morphology-driven gas sensing by fabricated fractals: A review

• Vishal Kamathe and
• Rupali Nagar

Beilstein J. Nanotechnol. 2021, 12, 1187–1208, doi:10.3762/bjnano.12.88

• gradient or a thermal gradient. The diffusivity and dynamic viscosity affect the way in which mass is transported on the substrate. These gradients cause a circulatory flow of fluid, influence the mass transport, and eventually result in differently patterned fractal structures. The effects are

Influence of the magnetic nanoparticle coating on the magnetic relaxation time

• Mihaela Osaci and
• Matteo Cacciola

Beilstein J. Nanotechnol. 2020, 11, 1207–1216, doi:10.3762/bjnano.11.105

• coefficient of dynamic viscosity, kB is the Boltzmann constant, and T is the temperature. After obtaining the effective magnetic relaxation time value of each nanoparticle, we can calculate the average effective magnetic relaxation time. The effective magnetic relaxation time is influenced by the magnetic

• , respectively, η is the dynamic viscosity coefficient, ri is the radius of the i-th nanoparticle, βi,tr(t) and βi,rot(t) are the random Brownian force and torque, respectively, Ii is the moment of inertia of the i-th nanoparticle, is the angular speed of the i-th nanoparticle, is the resultant of the

An investigation on the drag reduction performance of bioinspired pipeline surfaces with transverse microgrooves

• Weili Liu,
• Hongjian Ni,
• Peng Wang and
• Yi Zhou

Beilstein J. Nanotechnol. 2020, 11, 24–40, doi:10.3762/bjnano.11.3

• τ is the shear stress (Pa), μ is the dynamic viscosity of the fluid (Pa∙s); and du/dy is the velocity gradient (1/s). According to Equation 1, changing the turbulent boundary layer state in the vicinity of the wall for a decreased velocity gradient is an essential and appropriate measure to reduce

• for the wall (as shown in Figure 2). The desired velocity was achieved by adopting a steady mass flow boundary condition. (2) Incompressible water was used as continuous phase medium. The density was 998.2 kg/m3 and the dynamic viscosity was 0.001003 Pa∙s. (3) The pressure-velocity coupling scheme was

• - large eddy simulation; SST - shear stress transfer. Nomenclature τ - shear stress, Pa; y - normal distance from wall, m; μ - dynamic viscosity of fluid, Pa·s; v - kinematic viscosity, m2/s; du/dy - velocity gradient, 1/s; η - drag reduction rate, %; - Reynolds stress; Fs - average drag of a smooth

Design of a nanostructured mucoadhesive system containing curcumin for buccal application: from physicochemical to biological aspects

• Sabrina Barbosa de Souza Ferreira,
• Gustavo Braga,
• Évelin Lemos Oliveira,
• Jéssica Bassi da Silva,
• Hélen Cássia Rosseto,
• Lidiane Vizioli de Castro Hoshino,
• Mauro Luciano Baesso,
• Wilker Caetano,
• Craig Murdoch,
• Helen Elizabeth Colley and
• Marcos Luciano Bruschi

Beilstein J. Nanotechnol. 2019, 10, 2304–2328, doi:10.3762/bjnano.10.222

• in the dynamic viscosity and loss tangent were observed with increasing frequency (Figure 6C and 6D). The exception is for the loss tangent of the CUR systems evaluated at 25 °C, which remain constant at the majority of the frequencies. Moreover, the increase in temperature led to the increase of G

• with and without CUR was investigated as well. The systems displayed lower G’ values at low temperatures; however, high G” values were observed as the temperature was increased. Even with the incorporation of CUR, the dynamic viscosity increased significantly due to the increase in temperature and

Effects of surface charge and boundary slip on time-periodic pressure-driven flow and electrokinetic energy conversion in a nanotube

• Mandula Buren,
• Yongjun Jian,
• Yingchun Zhao,
• Long Chang and
• Quansheng Liu

Beilstein J. Nanotechnol. 2019, 10, 1628–1635, doi:10.3762/bjnano.10.158

• , and t is the time. From the continuity equation, we find ∂u/∂z = 0 and so u depends on the variables r and t. Therefore, the momentum balance equations for the incompressible viscous Newtonian liquid becomes where ρ is the mass density, μ is the dynamic viscosity, Es is the streaming electric field

Effect of electrospinning process variables on the size of polymer fibers and bead-on-string structures established with a 2³ factorial design

• Paulina Korycka,
• Adam Mirek,
• Katarzyna Kramek-Romanowska,
• Marcin Grzeczkowicz and
• Dorota Lewińska

Beilstein J. Nanotechnol. 2018, 9, 2466–2478, doi:10.3762/bjnano.9.231

• diameter of uniform and heterogeneous fibers (with and without bead-on-string structures) and the size of beads obtained during the electrospinning process. A 23 factorial design was performed to determine the influence of the following factors: electrical voltage, flow rate and dynamic viscosity of the

• fibers obtained during the electrospinning process. The literature analysis indicates that there are three process parameters with the most impact on the structure of fibrous mats: polymer solution dynamic viscosity (μ), electrical voltage (U) and solution flow rate (Q). The aim of the present study was

• procedures The dynamic viscosity of solutions was measured with a RheolabQC rotation viscometer at a predetermined temperature (25 °C). A scanning electron microscope (SEM, Hitachi TM-1000) was used to analyze the structure of the obtained electrospun mats. The samples of electrospun mats were sprayed with a

Enzymatically promoted release of organic molecules linked to magnetic nanoparticles

• Chiara Lambruschini,
• Silvia Villa,
• Luca Banfi,
• Fabio Canepa,
• Fabio Morana,
• Annalisa Relini,
• Paola Riani,
• Renata Riva and
• Fulvio Silvetti

Beilstein J. Nanotechnol. 2018, 9, 986–999, doi:10.3762/bjnano.9.92

• Nano ZS90 instrument (Malvern Instruments, UK ). The measurements parameters were as follows: scattering angle of 90°, measurement temperature of 20 °C, ethanol as dispersant (20 °C dynamic viscosity 1.23 mPa·s, refractive index 1.3617). DLS studies were carried out in general purpose mode (normal

Perfusion double-channel micropipette probes for oxygen flux mapping with single-cell resolution

• Yang Gao,
• Bin Li,
• Riju Singhal,
• Adam Fontecchio,
• Ben Pelleg,
• Zulfiya Orynbayeva,
• Yury Gogotsi and
• Gary Friedman

Beilstein J. Nanotechnol. 2018, 9, 850–860, doi:10.3762/bjnano.9.79

• is the pressure, is the unit vector, μ is the dynamic viscosity, and is the volume force field. Another study solved the convection diffusion equations (Equation 4 and Equation 5) for concentration distribution [45][46]: Where D is the diffusion coefficient, c is the species mass concentration, is

Graphene composites with dental and biomedical applicability

• Sharali Malik,
• Felicite M. Ruddock,
• Adam H. Dowling,
• Kevin Byrne,
• Wolfgang Schmitt,
• Ivan Khalakhan,
• Yoshihiro Nemoto,
• Hongxuan Guo,
• Lok Kumar Shrestha,
• Katsuhiko Ariga and
• Jonathan P. Hill

Beilstein J. Nanotechnol. 2018, 9, 801–808, doi:10.3762/bjnano.9.73

• in the fracture surface of the polymer matrix. The mean dynamic viscosity, compressive fracture strength and compressive modulus and associated standard deviations for the control group and the groups prepared with poly(acrylic acid) solutions containing graphene are shown in Table 2. There was a

• progressive significant increase in the dynamic viscosity of the poly(acrylic acid) solutions as the concentration of graphene added to the poly(acrylic acid) solutions was increased. This increase in viscosity with increasing nano-carbon concentration is consistent with that found by other researchers [17

• ][18]. Further increases in the amount of graphene added to the poly(acrylic acid) solutions – 2.0 mg, 5.0 mg and 10.0 mg all resulted in significant increases in dynamic viscosity compared with the control group as illustrated in Table 2. There was no significant trend in the compressive fracture

Optimal fractal tree-like microchannel networks with slip for laminar-flow-modified Murray’s law

• Dalei Jing,
• Shiyu Song,
• Yunlu Pan and
• Xiaoming Wang

Beilstein J. Nanotechnol. 2018, 9, 482–489, doi:10.3762/bjnano.9.46

• fluid flow in any single microchannel with boundary slip at the kth level can be expressed as follows [26] where RHk is the hydraulic resistance of fluid flow in any single microchannel at the kth level, and μ is the dynamic viscosity of the fluid flow. For the pressure-driven flow in a fractal tree

The nanofluidic confinement apparatus: studying confinement-dependent nanoparticle behavior and diffusion

• Stefan Fringes,
• Felix Holzner and
• Armin W. Knoll

Beilstein J. Nanotechnol. 2018, 9, 301–310, doi:10.3762/bjnano.9.30

• where kB is Boltzmann’s constant, T is the absolute temperature, and η is the dynamic viscosity of the continuous medium. The hydrodynamically hindered diffusion parallel to a single interface is conveniently given by a correction factor f||1: Solutions are given in terms of the dimensionless particle

Hyperthermic intracavitary nanoaerosol therapy (HINAT) as an improved approach for pressurised intraperitoneal aerosol chemotherapy (PIPAC): Technical description, experimental validation and first proof of concept

• Daniel Göhler,
• Stephan Große,
• Alexander Bellendorf,
• Thomas Albert Falkenstein,
• Mehdi Ouaissi,
• Jürgen Zieren,
• Michael Stintz and
• Urs Giger-Pabst

Beilstein J. Nanotechnol. 2017, 8, 2729–2740, doi:10.3762/bjnano.8.272

• temperature due to decreasing dynamic viscosity, density and surface tension of the liquid. To increase the droplet flux as well as the in-tissue drug penetration homogenously over the whole peritoneum, the HINAT-LAU aerosol is also unipolar-charged before entering the capnoperitoneum. For this purpose, an

Numerical investigation of the tribological performance of micro-dimple textured surfaces under hydrodynamic lubrication

• Kangmei Li,
• Dalei Jing,
• Jun Hu,
• Xiaohong Ding and
• Zhenqiang Yao

Beilstein J. Nanotechnol. 2017, 8, 2324–2338, doi:10.3762/bjnano.8.232

• number of independent variables, the dimensionless variables are defined as follows: where u, v and w are the velocities of the fluid along the x, y, and z axes, respectively; η is the dynamic viscosity; p is pressure; v0 is the characteristic velocity of the lubricant and p0 is the characteristic

Imidazolium-based ionic liquids used as additives in the nanolubrication of silicon surfaces

• Patrícia M. Amorim,
• Ana M. Ferraria,
• Rogério Colaço,
• Luís C. Branco and
• Benilde Saramago

Beilstein J. Nanotechnol. 2017, 8, 1961–1971, doi:10.3762/bjnano.8.197

• its mixtures with the ILs was measured with a viscometer DV-II+Pro (Brookfield) at 25 °C. All measurements were done in triplicate. The temperature uncertainty was ±0.02 °C, while the precision of the dynamic viscosity measurements was ±0.5%. The contact angle measurements on Si substrates were done

The effect of the electrical double layer on hydrodynamic lubrication: a non-monotonic trend with increasing zeta potential

• Dalei Jing,
• Yunlu Pan and
• Xiaoming Wang

Beilstein J. Nanotechnol. 2017, 8, 1515–1522, doi:10.3762/bjnano.8.152

• h under the combined actions of the EDL, the driving pressure and the lower sliding wall with a velocity of V, the velocity field ν and the relevant volume flow rate of the lubricant Q can be derived as, where μ is lubricant’s dynamic viscosity, dp/dx is pressure gradient, V is the sliding velocity

Electroviscous effect on fluid drag in a microchannel with large zeta potential

• Dalei Jing and
• Bharat Bhushan

Beilstein J. Nanotechnol. 2015, 6, 2207–2216, doi:10.3762/bjnano.6.226

• it is the original bulk electrical conductivity of the electrolyte. The flow field in the microchannel The governing equation of the electroviscous effect is given by the following modified Navier–Stokes equation, where μ is the dynamic viscosity of the electrolyte, v is the velocity of the fluid

An adapted Coffey model for studying susceptibility losses in interacting magnetic nanoparticles

• Mihaela Osaci and
• Matteo Cacciola

Beilstein J. Nanotechnol. 2015, 6, 2173–2182, doi:10.3762/bjnano.6.223

• is usually described by [2]: where Vih is the hydrodynamic volume and η is the coefficient of dynamic viscosity. Generally, the two processes are studied separately [2]. The relaxation process dominating the magnetic behaviour of the colloidal suspension is determined by the nanoparticle properties

• orientation of the anisotropy axis or anisotropy axis parallel with external magnetic field. We used an aqueous basic solution with a dynamic viscosity of 8.9·10−4 Pa·s, at the temperature T = 293 K. We applied a sinusoidal external magnetic field with an amplitude equal to 15 kA/m, at a frequency f = 300 kHz

Aquatic versus terrestrial attachment: Water makes a difference

• Petra Ditsche and
• Adam P. Summers

Beilstein J. Nanotechnol. 2014, 5, 2424–2439, doi:10.3762/bjnano.5.252

• have a significant effect on the types of forces acting to dislodge attached organisms. The first is density; water is around 1000 times denser than air, which means that both inertia and buoyancy are very different in these two fluids (Table 2). Second, air has just around 1.8% of the (dynamic

• ) viscosity of water, which affects the scale of forces between the fluid and the organism. Thirdly, water is a polar liquid while air is a largely inert gas. This difference has profound effects on physicochemical interactions in the dry and in the wet environment. Gravity Gravity is usually the most

The study of surface wetting, nanobubbles and boundary slip with an applied voltage: A review

• Yunlu Pan,
• Bharat Bhushan and
• Xuezeng Zhao

Beilstein J. Nanotechnol. 2014, 5, 1042–1065, doi:10.3762/bjnano.5.117

• dynamic viscosity of the liquid, V and R are the velocity and radius of the sphere, respectively, D is the separation distance, and k is the stiffness of the cantilever. The deflection of the cantilever can be obtained by the AFM. For slip length measurement, the driving velocity was 77 μm/s. Then the

• elementary charge. The net charge density ρe can be expressed by using a Boltzmann distribution as [90]: For a pressure-driven flow, when considering the electrical force exerted on the flow by the EDL, the flow can be described by a modified Navier–Stokes equation as [91]: where μ is the dynamic viscosity

Effect of spherical Au nanoparticles on nanofriction and wear reduction in dry and liquid environments

• Dave Maharaj and
• Bharat Bhushan

Beilstein J. Nanotechnol. 2012, 3, 759–772, doi:10.3762/bjnano.3.85

• be reduced with liquids of low viscosities [25]. Liquids such as glycerol and dodecane have been shown to reduce friction and wear. Glycerol has a dynamic viscosity (934 mPa·s) that is significantly higher than water (0.89 mPa·s) and studies were performed on the macroscale by using pin-on-disk

Dynamics of capillary infiltration of liquids into a highly aligned multi-walled carbon nanotube film

• Sławomir Boncel,
• Krzysztof Z. Walczak and
• Krzysztof K. K. Koziol

Beilstein J. Nanotechnol. 2011, 2, 311–317, doi:10.3762/bjnano.2.36

• liquid in a rate that can be linearly correlated to dynamic viscosity of the liquid (η). The experimental results follow the classical theory of capillarity for a steady process (Lucas–Washburn law), where the nanoscale capillary force, here supported by gravity, is compensated by viscous drag. This most

• general theory of capillarity can be applied in a prediction of both wettability of HACNT films and the dynamics of capillary rise in the intertube space in various technological applications. Keywords: capillary action; dynamic viscosity; highly aligned carbon nanotubes; superhydrophobicity; wettability

• meniscus of a given liquid, defines eventuality of infiltration. The second parameter, dynamic viscosity of the liquid, corresponds to the rate of infiltration or, in other words, dynamics of the capillary rise in the intertube space. As a model of HACNT film we used a CVD-grown array of a specified

Infrared receptors in pyrophilous (“fire loving”) insects as model for new un-cooled infrared sensors

• David Klocke,
• Anke Schmitz,
• Helmut Soltner,
• Herbert Bousack and
• Helmut Schmitz

Beilstein J. Nanotechnol. 2011, 2, 186–197, doi:10.3762/bjnano.2.22

• design of such a compensation leak. For the design of a compensation leak a formula will be derived. For a liquid as fluid a mass balance between the two volumes of the cavity and of the reservoir yields a system of two partial differential equations. with the following abbreviations: where η: dynamic

• viscosity, L: Length of canal, RL: Radius of canal. For the solution of the differential equations in Equation 9, a Hagen–Poiseuille flow in the canal is assumed [34][35]. where (dVL/dt): volumetric flow rate in the canal, PC(t), PR(t): time dependent pressures in the cavity and the reservoir. The solution