Article
Materials Science, Multidisciplinary
Xiaonan Wang, Dianzhen Wang, Shuailing Ma, Xinran Dong, Kaixuan Rong, Cun You, Fei Wang, Haibo Li, Dongfei Li, Qiang Tao, Pinwen Zhu
Summary: Breaking the contradictory of hardness and toughness in B4C is still a challenge. Composite B4C with carbon nanotubes (CNTs) improves toughness, but has limitations. In this study, inner compressive stress is introduced in B4C composite with single-walled carbon nanotube bundles (B4C-SWNTb) by high pressure and high temperature. The resulting B4C-2 vol% SWNTb composites possess optimal hardness and fracture toughness, 3.3 times higher than pure B4C.
MATERIALS TODAY COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Chao Chen, Yi-Ming Zhao, Hai-Long Yu, Xin-Yu Jiao, Xian-Gang Hu, Xin Li, Peng-Xiang Hou, Chang Liu, Hui-Ming Cheng
Summary: Bolometric photodetectors based on single-wall carbon nanotubes (SWCNTs) have advantages of ul-trawide absorption spectrum, high charge carrier mobility, good processability, and high mechanical flexibility. However, their detection performance needs improvement. We fabricated a flexible infrared photodetector based on high quality SWCNT films. The device exhibited an ul-trahigh detectivity and a short response time. The photocurrent response of the detector was influenced by the structure of the SWCNT network.
Article
Chemistry, Multidisciplinary
Lili Zhang, Ziwei Xu, Tian-liang Feng, Maoshuai He, Thomas Willum Hansen, Jakob Birkedal Wagner, Chang Liu, Hui-Ming Cheng
Summary: This study uses environmental transmission electron microscopy to observe for the first time the breaking of symmetry during the growth of a single-wall carbon nanotube. It reveals the role of topological defects and the importance of the tube-catalyst interface.
Article
Engineering, Environmental
Dan Wang, Tingchao Ji, Qi Jing, Wei He, Zeyuan Fan, Dejian Wu, Xinming Qian
Summary: The study investigated the minimum ignition temperature of three typical organic dusts in various atmospheres, revealing that CO2 is most effective in reducing ignition sensitivity. The risk of dust explosions significantly increases with higher oxygen mole fraction, as demonstrated by a logarithmic reduction in MIT for the three dusts.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Optics
Dalin Sun, Jihong Pei, Lang Sun, Shaowen Chu, Xintong Xu, Shuangchen Ruan
Summary: Researchers reported a wide-band single-walled carbon nanotube (SWCNT) saturable absorber (SA) fabricated in the one-dimensional nanochannels of ZnAPO4-5 (AFI) zeolite single crystals. The synthesized SA could be used for Q-switched operation in ytterbium- and thulium-doped fiber lasers at different wavelengths. The SWCNT@AFI crystal exhibited excellent anisotropic optical properties and was suitable for short-duration pulsed fiber lasers.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Energy & Fuels
Syed Muhammad Ali Haider, Bagh Ali, Qiuwang Wang, Cunlu Zhao
Summary: This study numerically simulated the rotational flow of nanofluids containing SWCNT and SWCNT-MWCNT over a stretching sheet, finding that enhancing the rotational parameter and magnetic field can improve thermal transport efficiency. The hybrid nanofluid showed higher velocities, temperatures, and microorganism concentrations compared to the mono nanofluid.
Article
Materials Science, Multidisciplinary
Ramesh Jayaraman, Andrew G. Rinzler
Summary: The use of a dual pulsed laser vaporization (DPLV) system in the synthesis of single-wall carbon nanotubes (SWCNT) revealed that the high material purities reported in early experiments, which were originally attributed to reaction volume confinement, were in part due to an unrecognized source of silicon. The inclusion of Si in the synthesis process correlated with an enhancement in product purity, as demonstrated through spectroscopic analysis. This finding suggests that the inclusion of Si may be beneficial in other methods of SWCNT production.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2023)
Article
Chemistry, Physical
Mochen Li, Kotaro Yasui, Hisashi Sugime, Suguru Noda
Summary: This study highlights the importance of maintaining a highly reductive atmosphere during annealing to achieve active catalyst particles with a higher number density and longer lifetime. Fe particles can be partially oxidized during annealing in a mildly oxidative CO2 environment, affecting the bulk diffusion of Fe into the AlOx layer. On the other hand, Fe remains active for SWCNT growth when reduced sufficiently in H-2 without CO2.
Article
Nanoscience & Nanotechnology
Alexander A. Tonkikh, Valentina A. Eremina, Ekaterina A. Obraztsova, Dmitry A. Musatov, Alexander Yu Pereyaslavtsev, Esko Kauppinen, Elena D. Obraztsova
Summary: The efficient method presented allows for tuning the optical and electrophysical parameters of macroscopic objects made from SWCNTs by filling the inner channels with acceptors and donors in gaseous conditions. This tuning method enables predictable shifts in Fermi level position and optical band gap edge value, with potential applications in various fields such as electrochemical, sensor, solar cell, or thermoelectric electrode materials.
ACS APPLIED NANO MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Zhaoqing Gao, Lele Xu, Xinyu Jiao, Xin Li, Chengjian He, Hao-Zike Wang, Chunyang Sun, Peng-Xiang Hou, Chang Liu, Hui-Ming Cheng
Summary: In this study, a strong connection between carbon nanotube fibers (CNTFs) and a copper matrix was achieved by introducing a nickel layer. The connection exhibits high mechanical strength and electrical conductivity, with a resistance change rate of only about 29.8% after multiple thermal shock cycles.
Article
Materials Science, Composites
Xiaoer Wang, Tianxiang Zhu, Zhen-Yan Deng, Xinluo Zhao
Summary: Short single-wall carbon nanotubes (SWCNTs)/epoxy composites with a low weight ratio of SWCNTs (0.03% to 0.5%) were fabricated. The tensile fracture strength initially increases with increasing SWCNT content, reaches a maximum at 0.05 wt%, and then decreases. A model analysis suggests that the transition from local matrix fracture to SWCNT debonding is responsible for the decrease in tensile strength. The study partly explains the variations in fracture strength observed in CNT reinforced composites.
POLYMER COMPOSITES
(2023)
Article
Chemistry, Multidisciplinary
Kunhua Lei, Sergei M. Bachilo, R. Bruce Weisman
Summary: Time-resolved fluorescence spectroscopy was used to investigate the displacement of adsorbed SDS from SWCNT surfaces by short strands of single-stranded DNA. The displacement rate showed a strong kinetic dependence on the oligomer length and SWCNT diameter. A two-step kinetic model was proposed to explain the findings, which involved the disruption of the original SDS coating and the conformational relaxation of ssDNA on the nanotube surface.
Article
Physics, Multidisciplinary
Souleymanou Abbagari, Alphonse Houwe, Lanre Akinyemi, Serge Yamigno Doka
Summary: In this paper, the dynamics of coupled nonlinear waves and the modulated wave patterns in a single-wall carbon nanotube are investigated. The effects of the inter-atomic interaction potential on bright and dark solitons and modulation instability are demonstrated using numerical simulations.
EUROPEAN PHYSICAL JOURNAL PLUS
(2023)
Article
Chemistry, Multidisciplinary
Juhi Srivastava, Anshu Gaur
Summary: Recent studies have shown that factors such as charge transfer, structural deformation, and van der Waals forces play crucial roles in affecting the vibrational properties of hybrid carbon nanostructures based on SWNTs and SLG. As the distance between SWNTs and SLG decreases, both charge transfer and van der Waals forces increase, with the latter having a relatively higher impact and likely being the main reason for larger Raman shifts observed at smaller separations.
NANOSCALE ADVANCES
(2021)
Article
Chemistry, Multidisciplinary
Lina Tizani, Yawar Abbas, Ahmed Mahdy Yassin, Baker Mohammad, Moh'd Rezeq
Summary: An optical rectenna was presented by engineering a rectifying diode between a metal probe of an AFM and a SWCNT acting as a nano-antenna. The study demonstrated the sensitivity of CNT-based rectenna to light and its potential applications in optical communication and energy harvesting systems.
Article
Multidisciplinary Sciences
Sophia Gershman, Maria B. Harreguy, Shurik Yatom, Yevgeny Raitses, Phillip Efthimion, Gal Haspel
Summary: The study successfully combined a flexible dielectric barrier discharge (flex-DBD) design with an environmentally safe chemical reagent to achieve surface decontamination from bacterial contaminants using plasma technology, dramatically improving disinfection efficiency.
SCIENTIFIC REPORTS
(2021)
Article
Physics, Fluids & Plasmas
Jacob Simmonds, Yevgeny Raitses, Andrei Smolyakov, Oleksandr Chapurin
Summary: Recent studies have shown that modulating the anode voltage of a Hall thruster can control its breathing oscillations and improve performance, but phase alignment between discharge current and voltage affects efficiency gains, while the outward shift of the acceleration region limits thrust increase. Mechanisms underlying the relative phase between discharge current, ion current, and discharge voltage are experimentally investigated and corroborated with one-dimensional hybrid simulations.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2021)
Article
Instruments & Instrumentation
S. M. Finnegan, M. E. Koepke, V. I. Demidov
Summary: This passage discusses the testing of an electrostatic Langmuir probe for real-time measurements in magnetized plasma. By adjusting the orientation of the probe and slots, accurate real-time measurements of ion temperature and space potential can be achieved.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
Article
Physics, Applied
Jacob Simmonds, Yevgeny Raitses
Summary: In wall-less Hall thrusters, ionization and ion acceleration occur outside the thruster, reducing interactions and promising longer lifespan. These non-conventional thrusters are simpler and easier to miniaturize for low power operation, but have lower performance due to larger plume divergence.
JOURNAL OF APPLIED PHYSICS
(2021)
Review
Physics, Fluids & Plasmas
C. Yuan, I. P. Kurlyandskaya, V. Demidov, M. Gryaznevich, M. E. Koepke, Y. Raitses
Summary: The application of the magnetically insulated baffled probe (MIBP) and MIBP cluster for studying properties of low-temperature and peripheral fusion plasmas reveals oscillations of fluid observables and plasma instabilities and waves.
PLASMA PHYSICS AND CONTROLLED FUSION
(2021)
Article
Physics, Applied
J. Simmonds, Y. Raitses
Summary: A wall-less Hall thruster, without the channel walls bounding the plasma, shows promising improvements in thruster performance when a biased segmented electrode is added to narrow the plasma plume and suppress discharge current oscillations. The physical mechanisms behind these effects are still unclear, but they appear to be related to reductions in electron cross field transport and changes in breathing mode frequency.
APPLIED PHYSICS LETTERS
(2021)
Article
Physics, Applied
Lubos Brieda, Yevgeny Raitses, Edgar Choueiri, Roger Myers, Michael Keidar
Summary: This article explores the feasibility of testing Hall effect thrusters in a quasi-steady mode by pulsing the mass flow rate between nominal and low values to address testing challenges caused by high power levels. Numerical simulations indicate that sub-second durations are sufficient to achieve steady-state current and flow field distributions, allowing characterization of thruster performance and the near plume region.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Physics, Applied
N. S. Chopra, Y. Raitses, S. Yatom, J. M. Munoz Burgos
Summary: In the atmospheric pressure anodic carbon arc, the ablation of the anode plays a crucial role in producing nanomaterials. This study reveals that the ablation of the graphite anode can occur in two distinctive modes, low and high ablation rates, depending on the power deposition and the gap between the anode and cathode electrodes. The findings show the presence of a positive anode sheath and a relatively low electron temperature, which were not fully accounted for in previous models. The results suggest the existence of other physical mechanisms that contribute to the electron attracting behavior of the anode sheath in this arc.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Physics, Fluids & Plasmas
Shubo Li, Chengxun Yuan, Iya P. Kurlyandskaya, V. Demidov, M. E. Koepke, Jingfeng Yao, Zhongxiang Zhou
Summary: A single magnetically insulated baffled probe (MIBP) was used to study oscillations in a magnetized plasma. The study showed that the single MIBP can provide useful information about oscillation amplitudes, cross-coherency, and cross-phase. It also explained how to determine the maximum and minimum possible values of electron temperature fluctuations for cases with two types of oscillations.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2022)
Article
Instruments & Instrumentation
A. Apponi, M. G. Betti, M. Borghesi, N. Canci, G. Cavoto, C. Chang, W. Chung, A. G. Cocco, A. P. Colijn, N. D'Ambrosio, N. de Groot, M. Faverzani, A. Ferella, E. Ferri, L. Ficcadenti, S. Gariazzo, F. Gatti, C. Gentile, A. Giachero, Y. Hochberg, Y. Kahn, A. Kievsky, M. Lisanti, G. Mangano, L. E. Marcucci, C. Mariani, M. Messina, E. Monticone, A. Nucciotti, D. Orlandi, F. Pandolfi, S. Parlati, C. Perez de los Heros, O. Pisanti, A. D. Polosa, A. Puiu, I Rago, Y. Raitses, M. Rajteri, N. Rossi, K. Rozwadowska, A. Ruocco, C. F. Strid, A. Tan, C. G. Tully, M. Viviani, U. Zeitler, F. Zhao
Summary: The paper presents the implementation and optimization methods of the PTOLEMY transverse drift filter for precise analysis of the energy spectrum of electrons near the tritium beta-decay endpoint. Simulation results show that low-energy electrons with an initial kinetic energy of 18.6 keV can be drained to < 10 eV using a 1 T iron core (or 3 T superconducting) starting field under low field operation conditions.
JOURNAL OF INSTRUMENTATION
(2022)
Article
Physics, Applied
O. Chapurin, A. I. Smolyakov, G. Hagelaar, J. -p. Boeuf, Y. Raitses
Summary: Low-frequency axial oscillations in the range of 5-50 kHz are commonly observed in Hall thrusters. The exact mechanisms of these instabilities are not yet clear. Researchers have developed a one-dimensional time-dependent full nonlinear low-frequency model to study the physics of these oscillations. The model is compared to a hybrid model with kinetic ions and neutrals. It is found that both models exhibit two main regimes: one with pure low-frequency behavior and the other with coexisting low-frequency and high-frequency (100-200 kHz) oscillations. The effect of injecting neutrals with finite temperature is also studied, showing a significant suppression effect on the oscillation amplitude.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Physics, Fluids & Plasmas
M. Tyushev, M. Papahn Zadeh, V. Sharma, M. Sengupta, Y. Raitses, J. -p. Boeuf, A. Smolyakov
Summary: In this study, azimuthal structures in cylindrical Penning discharge are investigated using a 2D3V radial-azimuthal PIC/MCC model with the axial magnetic field. The discharge is self-consistently supported by ionization due to the axial injection of electrons. Two different regimes with different types of observed azimuthal structures are identified in the steady-state discharge, and the transition between the regimes is controlled by the mechanism of the energy input to the discharge. The presence of large (m = 1) spoke and small-scale spiral structures is attributed to Simon-Hoh and lower hybrid instabilities driven by the electric field, density gradient, and collisions.
PHYSICS OF PLASMAS
(2023)
Article
Astronomy & Astrophysics
A. Apponi, M. G. Betti, M. Borghesi, A. Boyarsky, N. Canci, G. Cavoto, C. Chang, V Cheianov, Y. Cheipesh, W. Chung, A. G. Cocco, A. P. Colijn, N. D'Ambrosio, N. de Groot, A. Esposito, M. Faverzani, A. Ferella, E. Ferri, L. Ficcadenti, T. Frederico, S. Gariazzo, F. Gatti, C. Gentile, A. Giachero, Y. Hochberg, Y. Kahn, M. Lisanti, G. Mangano, L. E. Marcucci, C. Mariani, M. Marques, G. Menichetti, M. Messina, O. Mikulenko, E. Monticone, A. Nucciotti, D. Orlandi, F. Pandolfi, S. Parlati, C. Pepe, C. Perez de los Heros, O. Pisanti, M. Polini, A. D. Polosa, A. Puiu, I Rago, Y. Raitses, M. Rajteri, N. Rossi, K. Rozwadowska, I Rucandio, A. Ruocco, C. F. Strid, A. Tan, L. K. Teles, V Tozzini, C. G. Tully, M. Viviani, U. Zeitler, F. Zhao
Summary: We discuss the consequences of quantum uncertainty on the spectrum of electrons emitted by the beta-processes of a tritium atom bound to a graphene sheet. We propose possible avenues to mitigate the effect of quantum uncertainty.
Article
Engineering, Aerospace
Jacob Simmonds, Yevgeny Raitses
Summary: This study revisits the conventional definitions of plasma thruster performance parameters to account for time variations, finding that modulating ion energy can maximize thrust but also introduce inefficiencies. It is shown that thrust can potentially change over 20% due to sinusoidal oscillations, highlighting the importance of understanding and controlling unstable plasma behavior in thruster design.
JOURNAL OF PROPULSION AND POWER
(2021)
