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

• factors on the simulation results, the calculations used the same parameter settings, and the specific conditions were set as follows: (1) The periodic boundary condition was adopted along the flow direction to guarantee the turbulent flow was fully developed. The no-slip boundary condition was adopted

• . Hence, a maximum DRR of 6.26% could be achieved using the optimal microgroove parameters. By using the same method, orthogonal simulated calculations were carried out under different velocities both in the pipe and in an annulus flow. Figure 13 shows the DRR of different numerical tests at flow

Synthesis of amorphous and graphitized porous nitrogen-doped carbon spheres as oxygen reduction reaction catalysts

• Maximilian Wassner,
• Markus Eckardt,
• Andreas Reyer,
• Thomas Diemant,
• Michael S. Elsaesser,
• R. Jürgen Behm and
• Nicola Hüsing

Beilstein J. Nanotechnol. 2020, 11, 1–15, doi:10.3762/bjnano.11.1

• explain the increase of the ORR activity with higher nitriding temperatures, since previous calculations indicated that the ORR activity of the nitrided carbon catalysts results from the carbon edge atoms of micropores in low-level N-doped (graphitic and pyridinic N) graphene structures [24][26]. Thus

• be correlated with the ORR activity [17][18][19][20][21], is only slightly lower for nitriding at 1000 °C compared to nitriding at 700 °C. Hence, none of these different nitrogen configurations can simply explain the trend in the ORR activity. This agrees with the results of DFT-based calculations of

• a comparable model system, which showed that the active sites are not the N-sites themselves but rather carbon atoms at edge sites of pores in N-doped graphenic layers [26]. These calculations showed that too high amounts of N-doping and thus of graphitic N-sites can impair the ORR activity, in

Plasmonic nanosensor based on multiple independently tunable Fano resonances

• Lin Cheng,
• Zelong Wang,
• Xiaodong He and
• Pengfei Cao

Beilstein J. Nanotechnol. 2019, 10, 2527–2537, doi:10.3762/bjnano.10.243

• calculations of the individual components. Funding This work was supported by the National Natural Science Foundation of China (No. 61804071), the Natural Science Foundation of Gansu Province (Nos. 1606RJZA068 and 18JR3RA297), and the Fundamental Research Funds for the Central Universities of China (lzujbky

Formation of metal/semiconductor Cu–Si composite nanostructures

• Natalya V. Yumozhapova,
• Andrey V. Nomoev,
• Vyacheslav V. Syzrantsev and
• Erzhena C. Khartaeva

Beilstein J. Nanotechnol. 2019, 10, 2497–2504, doi:10.3762/bjnano.10.240

• molecular dynamics research package [25]. A part of the calculations was performed using the resources of the Information and Computing Center of the Novosibirsk State University. Results and Discussion Modelling a free spherical cluster of a copper/silicon alloy We considered a free spherical cluster of a

• appearance of oxygen in the compound with silicon is due to its presence in copper and the oxidation of silicon in air after production. The calculations and the comparison with experiments demonstrate that it is possible to obtain composite nanoparticles with different content and distribution of components

Abrupt elastic-to-plastic transition in pentagonal nanowires under bending

• Sergei Vlassov,
• Magnus Mets,
• Boris Polyakov,
• Jianjun Bian,
• Leonid Dorogin and
• Vahur Zadin

Beilstein J. Nanotechnol. 2019, 10, 2468–2476, doi:10.3762/bjnano.10.237

• for clarity. Bending of an alumina-coated silver NW. No breaking or abrupt deformation were observed even for relatively high bending curvatures. Supporting Information Supporting Information File 306: Additional figures and a video link. Acknowledgements MD modeling and calculations were supported

Mobility of charge carriers in self-assembled monolayers

• Zhihua Fu,
• Tatjana Ladnorg,
• Hartmut Gliemann,
• Alexander Welle,
• Asif Bashir,
• Michael Rohwerder,
• Qiang Zhang,
• Björn Schüpbach,
• Andreas Terfort and
• Christof Wöll

Beilstein J. Nanotechnol. 2019, 10, 2449–2458, doi:10.3762/bjnano.10.235

• , Figure S1). Further characterization methods such as infrared reflection absorption spectroscopy (IRRAS) and attenuated transmission reflection (ATR) spectroscopy were also applied. The assignment of the molecular vibrations was aided by quantum-chemical calculations, from which the transition dipole

Coating of upconversion nanoparticles with silica nanoshells of 5–250 nm thickness

• Cynthia Kembuan,
• Maysoon Saleh,
• Bastian Rühle,
• Ute Resch-Genger and
• Christina Graf

Beilstein J. Nanotechnol. 2019, 10, 2410–2421, doi:10.3762/bjnano.10.231

• calculations. The oleate ligands are, however, exchanged during shell growth in the inverse microemulsion [36][47]. The oleate content for particles of this size was in the range of 5–10 wt % as shown by thermogravimetric analysis [57]. The z-average values of the samples after the first and second shell

Semitransparent Sb₂S₃ thin film solar cells by ultrasonic spray pyrolysis for use in solar windows

• Jako S. Eensalu,
• Atanas Katerski,
• Erki Kärber,
• Lothar Weinhardt,
• Monika Blum,
• Clemens Heske,
• Wanli Yang,
• Ilona Oja Acik and
• Malle Krunks

Beilstein J. Nanotechnol. 2019, 10, 2396–2409, doi:10.3762/bjnano.10.230

• , is found at 151 eV and ascribed to Sb 5s-derived states by comparison with band structure and density of states calculations [50]. Lastly, transitions from the upper valence band of Sb2S3 can be found centered at around 156 eV. These transitions were identified in line with atom-decomposed density of

Deterministic placement of ultra-bright near-infrared color centers in arrays of silicon carbide micropillars

• Stefania Castelletto,
• Abdul Salam Al Atem,
• Faraz Ahmed Inam,
• Hans Jürgen von Bardeleben,
• Sophie Hameau,
• Ahmed Fahad Almutairi,
• Gérard Guillot,
• Shin-ichiro Sato,
• Alberto Boretti and
• Jean Marie Bluet

Beilstein J. Nanotechnol. 2019, 10, 2383–2395, doi:10.3762/bjnano.10.229

• micropillars We model the emission of color centers in the pillars using the finite-element method COMSOL Multiphysics radio frequency module. A VSi color center is modeled as an oscillating point dipole located along the central axis of the SiC pillar. For calculations we used the index of refraction of the

• single emitter [8]. Other non-radiative decays due to phonon sideband and thermal dephasing are neglected here. From the collection efficiency calculations, we found the collection efficiency to be substantially enhanced for dipole emission in the SiC pillar. For a dipole oriented 8° off the c-axis, the

• %. In the FE calculations, we saw successive periodic peaks in the FE enhancement factor along the length of the pillar, with a spacing between the peaks of 400–450 nm, which is about half of the dipole emission wavelength (Figure 8b, circles). The first peak appears at ca. 400 nm from the top surface

Dynamics of superparamagnetic nanoparticles in viscous liquids in rotating magnetic fields

• Nikolai A. Usov,
• Ruslan A. Rytov and
• Vasiliy A. Bautin

Beilstein J. Nanotechnol. 2019, 10, 2294–2303, doi:10.3762/bjnano.10.221

• .10.221 Abstract The dynamics of magnetic nanoparticles in a viscous liquid in a rotating magnetic field has been studied by means of numerical simulations and analytical calculations. In the magneto-dynamics approximation three different modes of motion of the unit magnetization vector and particle

• geometric and magnetic parameters of the nanoparticles, as well as the amplitudes and frequencies at which the SAR of the superparamagnetic nanoparticle assembly in RMFs will be large enough to be used in magnetic hyperthermia. In this work, detailed numerical calculations of the SAR in RMFs for a dilute

• the particle director. On the plane of parameters (f, H0) three domains for different modes of motion of the unit magnetization vector and particle director are distinguished. The boundaries between these domains, first determined numerically, are then confirmed by analytical calculations. Then, the

Liquid crystal tunable claddings for polymer integrated optical waveguides

• José M. Otón,
• Manuel Caño-García,
• Fernando Gordo,
• Eva Otón,
• Morten A. Geday and
• Xabier Quintana

Beilstein J. Nanotechnol. 2019, 10, 2163–2170, doi:10.3762/bjnano.10.209

• configuration. The outputs are shown in the inset below (the actual power distribution is about 95:5, but the picture is saturated). LC-cladding of inorganic core MMIs Confinement of radiation can also be achieved through increasing the core refractive index. Hence, calculations have been performed using an

•  7 shows the results obtained under the same conditions as in the previous calculations, except that the core height has been reduced to 0.3 µm. The refractive index of the LC cladding has been varied from 1.50 to nearly 2.10; in the Figure, the region of interest from neff = 2.04 to neff = 2.06 has

Synthesis of highly active ETS-10-based titanosilicate for heterogeneously catalyzed transesterification of triglycerides

• Muhammad A. Zaheer,
• David Poppitz,
• Khavar Feyzullayeva,
• Marianne Wenzel,
• Jörg Matysik,
• Radomir Ljupkovic,
• Aleksandra Zarubica,
• Alexander A. Karavaev,
• Andreas Pöppl,
• Roger Gläser and
• Muslim Dvoyashkin

Beilstein J. Nanotechnol. 2019, 10, 2039–2061, doi:10.3762/bjnano.10.200

Improvement of the thermoelectric properties of a MoO₃ monolayer through oxygen vacancies

• Wenwen Zheng,
• Wei Cao,
• Ziyu Wang,
• Huixiong Deng,
• Jing Shi and
• Rui Xiong

Beilstein J. Nanotechnol. 2019, 10, 2031–2038, doi:10.3762/bjnano.10.199

• calculations; molybdenum trioxides; MoO3 monolayer; oxygen vacancies; thermoelectric properties; Introduction Thermoelectric materials that can directly convert temperature gradients to voltage gradients and vice versa provide a valid strategy to mitigate the global energy crisis. Owing to the unique ability

• -principles calculations. The calculations of the electrical properties of the MoO3 monolayer are performed using density functional theory (DFT) as implemented in the Vienna ab initio simulation package (VASP) code [18][19]. We utilize the generalized gradient approximation (GGA) of the Perdew–Burke

• donors and destroy the crystal symmetry, thereby enlarging the carrier concentration. Conclusion In summary, we have presented a comprehensive study of the thermoelectric properties of the MoO3 monolayer by first-principles calculations and Boltzmann transport theory. Our results indicate that the MoO3

Review of advanced sensor devices employing nanoarchitectonics concepts

• Katsuhiko Ariga,
• Tatsuyuki Makita,
• Masato Ito,
• Taizo Mori,
• Shun Watanabe and
• Jun Takeya

Beilstein J. Nanotechnol. 2019, 10, 2014–2030, doi:10.3762/bjnano.10.198

• interfacial types and nanoarchitectonics of interfacial structures. The above-mentioned specific features at the interfacial media were also proved by theoretical calculations based on quantum chemistry [152][153][154]. Even without direct contact, the low dielectric nature in nonpolar media located close to

First principles modeling of pure black phosphorus devices under pressure

• Ximing Rong,
• Zhizhou Yu,
• Zewen Wu,
• Junjun Li,
• Bin Wang and
• Yin Wang

Beilstein J. Nanotechnol. 2019, 10, 1943–1951, doi:10.3762/bjnano.10.190

• first principles calculations. The zigzag BP devices and the armchair BP devices exhibit different conductance–pressure relationships. For the zigzag BP devices conductance is robust against stress when the out-of-plane pressure ratio is less than 15%, and then increases rapidly until the conductive

• orthorhombic semiconductor to a simple cubic metal with increasing pressure by performing in situ ADXRD and Raman spectroscopy with the assistance of a DAC apparatus. They also carried out first principles calculations to interpret the metallic behavior of BP under pressure. Pablo et al. investigated the

• accumulated isotropically in strain-reduced regions, instead of occurring in the regions with a high tensile strain like in MoS2. Deniz et al. investigated the strain-related optical properties of monolayer BP using first principles calculations [7]. They found that the optical response of BP is sensitive to

Charge-transfer interactions between fullerenes and a mesoporous tetrathiafulvalene-based metal–organic framework

• Manuel Souto,
• Joaquín Calbo,
• Samuel Mañas-Valero,
• Aron Walsh and
• Guillermo Mínguez Espallargas

Beilstein J. Nanotechnol. 2019, 10, 1883–1893, doi:10.3762/bjnano.10.183

• electron-donor TTF ligand is studied in detail by means of different spectroscopic techniques and density functional theory (DFT) calculations. Importantly, gas sorption measurements demonstrate that sorption capacity is maintained after encapsulation of fullerenes, whereas the electrical conductivity is

• fullerenes has been carried out by different spectroscopic techniques and theoretical calculations. Gas sorption measurements demonstrate that permanent porosity is retained, whereas electrical measurements show that conductivity is enhanced after C60 encapsulation. Results and Discussion Synthesis and

• intermolecular CT excitation between the C60 and TTF ligands, as supported by theoretical calculations (see below). The experimental optical bandgap calculated from the onset is near 1.4 eV (885 nm), which is in agreement with the calculated electrochemical bandgap (1.43 eV) since the redox potential of TTF

Long-term entrapment and temperature-controlled-release of SF₆ gas in metal–organic frameworks (MOFs)

• Hana Bunzen,
• Andreas Kalytta-Mewes,
• Leo van Wüllen and
• Dirk Volkmer

Beilstein J. Nanotechnol. 2019, 10, 1851–1859, doi:10.3762/bjnano.10.180

• simulations Theoretical calculations were performed in order to determine the activation energy parameters from atomistic simulation data. Briefly, the approach previously described for scanning the minimum energy path of xenon atoms crossing the small pore in MFU-4 [13] was adapted and further refined in

• the displayed path. To obtain a rough estimate for the energy changes along the path, molecular mechanics calculations were performed, employing the universal force field (UFF) [35] parameters as included in the GULP code [36]. In order to prevent an origin shift of the framework during transition

• interaction energy, thus leading to a strong geometric distortion of the small pores of MFU-4. The energy minima are located at c/47 (marked by “min”) and c/152; According to force field calculations, another (local) energy minimum is found in the middle of the pore (c/100, “centre”), which is surprising in

Prestress-loading effect on the current–voltage characteristics of a piezoelectric p–n junction together with the corresponding mechanical tuning laws

• Wanli Yang,
• Shuaiqi Fan,
• Yuxing Liang and
• Yuantai Hu

Beilstein J. Nanotechnol. 2019, 10, 1833–1843, doi:10.3762/bjnano.10.178

• F/m. The relative carrier concentrations in our calculations are taken as pp0 = nn0 = 1 × 1021 m−3 and np0 = pn0 = 1 × 1011 (m−3), unless otherwise stated. The doping concentrations can be expressed as NA = ND = 1 × 1021 m−3. The lengths involved are taken as Ll = Lr = L = 10ll, unless otherwise

Growth dynamics and light scattering of gold nanoparticles in situ synthesized at high concentration in thin polymer films

• Corentin Guyot,
• Philippe Vandestrick,
• Ingrid Marenne,
• Olivier Deparis and
• Michel Voué

Beilstein J. Nanotechnol. 2019, 10, 1768–1777, doi:10.3762/bjnano.10.172

• neglectable. Theoretical calculations were made using the Maxwell–Garnett effective medium approximation (MG-EMA) for spherical nanoparticles (Figure S3, Supporting Information File Supporting Information File 1). They showed that, at the operating wavelength of the ellipsometer and at the doping levels

Remarkable electronic and optical anisotropy of layered 1T’-WTe₂ 2D materials

• Qiankun Zhang,
• Rongjie Zhang,
• Jiancui Chen,
• Wanfu Shen,
• Chunhua An,
• Xiaodong Hu,
• Mingli Dong,
• Jing Liu and
• Lianqing Zhu

Beilstein J. Nanotechnol. 2019, 10, 1745–1753, doi:10.3762/bjnano.10.170

• magnetoresistance (MR) behavior, which was attributed to its perfect electron–hole compensation. Theoretical calculations and experiments have indicated that WTe2 has a complicated electronic structure with more than two bands presenting at the Fermi level [17]. Meanwhile, it was believed to a wonderful candidate

• . Interestingly, although all of the TMDCs have the same formula, the atomic structure of 1T’-phase WTe2 is totally different from the other TMDCs. 1T’-WTe2 exhibits a distorted structure relative to the 1T’ phase. Both Raman [23][24] and first-principles [25][26] calculations have been used to indicate that

Tuning the performance of vanadium redox flow batteries by modifying the structural defects of the carbon felt electrode

• Ditty Dixon,
• Deepu Joseph Babu,
• Aiswarya Bhaskar,
• Hans-Michael Bruns,
• Joerg J. Schneider,
• Frieder Scheiba and
• Helmut Ehrenberg

Beilstein J. Nanotechnol. 2019, 10, 1698–1706, doi:10.3762/bjnano.10.165

• . More recently, Xu et al. showed, using first-principle calculations, that N-doping (especially the pyridinic and pyrrolic forms) enhances the water adsorption or hydrophilicity of the graphite electrode [24]. Thus, it may be concluded that the pyridinic and pyrrolic nitrogen formed during the N2-plasma

Giant magnetoresistance ratio in a current-perpendicular-to-plane spin valve based on an inverse Heusler alloy Ti₂NiAl

• Yu Feng,
• Zhou Cui,
• Bo Wu,
• Jianwei Li,
• Hongkuan Yuan and
• Hong Chen

Beilstein J. Nanotechnol. 2019, 10, 1658–1665, doi:10.3762/bjnano.10.161

• Heusler alloys in spintronics devices. By performing first principles calculations combined with the nonequilibrium Green’s function, it is revealed that spin magnetic moments of interfacial atoms suffer a decrease, and the electronic structure shows that the TiNiB-terminated structure possesses the

• % [9]. Several CPP-SVs have employed conventional Heusler alloys such as Co2Fe0.4Mn0.6Si [10] and Co2MnSi [11], also reaching a high MR ratio. On the other hand, a state-of-the-art theoretical approach that combines first principles calculations with the Keldysh nonequilibrium Green’s function theory

• largest MR value and can be regarded as a promising candidate for furture spintronics devices. Conclusion By employing first principles calculations combined with the nonequilibrium Green’s function, we studied the interfacial magnetic properties, interfacial electronic structure and spin transport

Subsurface imaging of flexible circuits via contact resonance atomic force microscopy

• Wenting Wang,
• Chengfu Ma,
• Yuhang Chen,
• Lei Zheng,
• Huarong Liu and
• Jiaru Chu

Beilstein J. Nanotechnol. 2019, 10, 1636–1647, doi:10.3762/bjnano.10.159

• calculations provide a guide to optimizing parameter settings for the nondestructive diagnosis of flexible circuits. Defect detection of the embedded circuit pattern was also carried out, which indicates the capability of imaging tiny subsurface structures smaller than 100 nm by using CR-AFM. Keywords: atomic

• into account for a blunt conical tip [34][35]. In our calculations, a half-cone angle of 15° was determined for the adopted probes, which was in accordance with the manufacturer’s specifications. The tip apex radius was averaged to be approximately 50 nm according to scanning electron microscopy

• % in this radius range even when a large normal force of 1000 nN is applied for the typical sample with a cover layer thickness of 50 nm. Therefore, we can safely assume the tip radius of 50 nm without significant errors. Similar calculations also demonstrated that the approximation of a sharp conical

Kelvin probe force microscopy work function characterization of transition metal oxide crystals under ongoing reduction and oxidation

• Dominik Wrana,
• Karol Cieślik,
• Wojciech Belza,
• Christian Rodenbücher,
• Krzysztof Szot and
• Franciszek Krok

Beilstein J. Nanotechnol. 2019, 10, 1596–1607, doi:10.3762/bjnano.10.155

• abundant adsorbates, also mimicking the typical operating temperatures of metal oxide gas sensors [51]. Numerical calculations suggest that H2O and CO2 species present in air saturate almost all free adsorption sites on TiO2-terminated SrTiO3(100) [52]. The low Redhead desorption temperature of H2O (CO2

Graphynes: an alternative lightweight solution for shock protection

• Kang Xia,
• Haifei Zhan,
• Aimin Ji,
• Jianli Shao,
• Yuantong Gu and
• Zhiyong Li

Beilstein J. Nanotechnol. 2019, 10, 1588–1595, doi:10.3762/bjnano.10.154

• reported for GYs using reactive force field (ReaxFF) potential calculations [15]. These results indicate excellent mechanical properties of GYs compared with conventional engineering materials [18][19][20][21]. Therefore, considering their low density, it is of great interest to investigate the application

• graphene. x- and y-axis are the lattice direction shown in Figure 1. For graphene and α-GY, x- and y-axis are the zigzag and armchair lattice directions, respectively. The values in brackets are from theoretical calculations based on the reported Young’s modulus from literature [2][32]. Supporting