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Levitation of pollen particles has been demonstrated in a radio frequency (RF) plasma. Pollen particles from Japanese cypress are levitated to various heights from lower electrode, where they spontaneously form quasi ordered state. Levitating pollen particles are identified from divinylbenzene particles in real-time using the polarization imaging technique.

Promoting the Li2O2 particles formation in the electrolyte by soluble catalysts could achieve high capacities for Li–O2 cell. However, side reactions between the soluble catalysts and lithium metal anode and more importantly, the deposition of the solid Li2O2 particle on which side (lithium anode or oxygen cathode) is inevitable for the solution phase discharge process in Li–O2 batteries, leading to the obvious capacity decay. Here we design and create a partial soluble metal nitroxides frameworks (MNOFs) to promote the “marriage” between the soluble and solid catalysts to overcome the most stubborn of these challenges. Taking advantage of the partial soluble property in the electrolyte, the prepared MNOFs can be simultaneously applied as the soluble and solid catalysts. MNOFs dissolving balance between electrolyte and cathode could construct a bridge between the electrolyte and cathode, which can not only suppress the corrosion reactions on Li anode, but also target discharge products deposition on the cathode. A 1Ah Li–O2 cell with a high areal specific capacity of 40 ​mA ​h ​cm-2 was demonstrated under a relatively low overpotential (~ 0.6 ​V). By ideally bridging the soluble and solid catalyst, the reversibility is significantly improved.

Construction of the JT-60SA tokamak was completed on schedule in March 2020. Manufacture and assembly of all the main tokamak components satisfied technical requirements, including dimensional accuracy and functional performances. Development of the plasma heating systems and diagnostics have also progressed, including the demonstration of the favourable electron cyclotron range of frequency (ECRF) transmission at multiple frequencies and the achievement of long sustainment of a high-energy intense negative ion beam. Development of all the tokamak operation control systems has been completed, together with an improved plasma equilibrium control scheme suitable for superconducting tokamaks including ITER. For preparation of the tokamak operation, plasma discharge scenarios have been established using this advanced equilibrium controller. Individual commissioning of the cryogenic system and the power supply system confirmed that these systems satisfy design requirements including operational schemes contributing directly to ITER, such as active control of heat load fluctuation of the cryoplant, which is essential for dynamic operation in superconducting tokamaks. The integrated commissioning (IC) is started by vacuum pumping of the vacuum vessel and cryostat, and then moved to cool-down of the tokamak and coil excitation tests. Transition to the super-conducting state was confirmed for all the TF, EF and CS coils. The TF coil current successfully reached 25.7 kA, which is the nominal operating current of the TF coil. For this nominal toroidal field of 2.25 T, ECRF was applied and an ECRF plasma was created. The IC was, however, suspended by an incident of over current of one of the superconducting equilibrium field coil and He leakage caused by insufficient voltage holding capability at a terminal joint of the coil. The unique importance of JT-60SA for H-mode and high-β steady-state plasma research has been confirmed using advanced integrated modellings. These experiences of assembly, IC and plasma operation of JT-60SA contribute to ITER risk mitigation and efficient implementation of ITER operation.

A crystallike structure was successfully formed as a result of the levitation of a kind of bacillus microorganisms $Klebsiella ~pneumoniae$ in a radio frequency (RF) plasma. The crystallike structure was confirmed to be hexagonal from top-view photograph. Neutral gas friction cools the particles down to equilibrium positions. Field Emission Scanning Electron Microscope (FE-SEM) measurement suggests that RF plasma processes the surface of levitating microorganisms.

As a novel therapy for peritoneal dissemination, it is desired to actualize an endoscopic photothermal therapy, which is minimally invasive and is highly therapeutically effective. However, since the endoscopic tumor temperature control has not been actualized, conventional therapies could damage healthy tissues by overhearing. In this paper, we develop a thermal endoscope system that controls the tumor temperature so that the heated tumor gets necrotic. In fact, our thermal endoscope contains a thermal image sensor, a visible light endoscope and a laser fiber. Concerning the thermal image sensor, the conventional thermal endoscope has the problem that the diameter is too large, because the conventional endoscope loads a large thermal image sensor with high-resolution. Therefore, this paper uses a small thermal image sensor with low resolution, because the diameter of the thermal endoscope needs to be smaller than 15mm in order to be inserted into the trocar. However, this thermal image sensor is contaminated by much noise. Thus, we develop a tumor temperature control system using a feedback control and tumor temperature estimation based on Gaussian function, so that the noisy, small thermal image sensor can be used. As experimental results of the proposed endoscopic photothermal therapy for the hepatophyma carcinoma model of rats, it turns out that the tumor temperature by which the heated tumor gets necrotic can be kept stable. It can be said that our endoscopic photothermal therapy achieves a certain degree of therapy effect.

Volume expansion during the discharging and charging processes is still a challenge for high-capacity electrode materials. The direct design of active materials with high surface area can overcome this challenge, but would inevitably decrease the volumetric energy density. Herein, a quasi-amorphous disordered microstructure of MoS2, combined with a conductive matrix, was designed to improve the cyclability and high rate performance. The hybrid electrode materials with optimized architecture have shown the buffering effect of the loosened structure and the enhanced conductivity. Moreover, this special structure has favoured pseudocapacitive charge storage behaviour, further contributing to the excellent electrochemical performance. As expected, after 3000 cycles, the reversible capacities remained as high as 322 mA h g−1 (1 A g−1) and 281.6 mA h g−1 (2 A g−1), both presenting low cyclic fading rates of 0.01% per cycle. After 1000 cycles at 6 A g−1, a capacity of 226.7 mA h g−1 was achieved. Even at an extremely high current density of 45 A g−1, it could still deliver a high capacity of 257.7 mA h g−1. We anticipate that suitable structure modulations might be applied to other electrode materials to meet the optimal electrochemical reaction and kinetic requirements.

Lattice modification by incorporating heteroatoms could effectively and precisely tune their intrinsic properties to get improved sinterability and electrochemical performance. Here, by introducing Cu2+ into the interstitial position of a ABO3-type perovskite, a 2 times higher protonic conductivity (1.9 × 10–2 S cm–1 at 700 °C) and low-temperature (1200 °C) sinterability were achieved for the BaCe0.68Zr0.1Y0.1Yb0.1Cu0.02O3−δ (BCZYYC2) electrolyte, compared to the precursor electrolyte. Meanwhile, the modified BCZYYC2 also exhibits excellent chemical stability in high-temperature and high-humidity conditions, as well as good compatibility with the components of cell. When used as the electrolyte in reversible fuel cell (FC)/electrolysis cell (EC) operational modes, the reversible solid oxide cell with the BCZYYC2 electrolyte illustrates prominent FC (0.85 W cm–2 at 700 °C) and EC (−1.96 A cm–2 at 700 °C and 1.3 V) performances with high film–electrolyte conductivity (8.7 × 10–3 S cm–1 at 700 °C). Additiona...

Development of highly efficient catalysts based on transition metal oxides (TMOs) is desirable and remains a big challenge for lithium-oxygen (Li-O2) batteries. In the present work, atomic-thick TiO2(B) nanosheets decorated with ultrafine Co3O4 nanocrystals (Co3O4-TiO2(B)) were synthesized and utilized as cathode catalyst in Li-O2 batteries by designing a hybrid and inducing oxygen vacancies. The XPS characterization results suggested that the introduction of Co3O4 nanocrystals could induce numerous oxygen vacancies in the TiO2(B) nanosheets through Co doping in the hybrid catalyst. The subsequent electrochemical experiments indicated that the Li-O2 batteries with the prepared hybrid catalysts showed high specific capacity (11000 mAhg-1), and good cycling stability (200 cycles at a limited capacity of 1000 mAhg-1) with low polarization (above 2.7 V for discharge medium voltage and below 4.0 V for charge medium voltage within 80 cycles). Furthermore, a possible working mechanism was proposed for a better understanding of the high performance of Co3O4-TiO2(B) catalysts for the Li-O2 batteries. This work also provided new insights into designing efficient catalysts through interface engineering between 2D (two-dimensional) TMOs and 0D (zero-dimensional) TMOs for Li-O2 batteries or other catalysis-related fields.

Solid polymer electrolytes (SPEs) have shown extraordinary promise for all-solid-state lithium metal batteries with high energy density and flexibility but are mainly limited by low ionic conductivity and their poor stability with lithium metal anodes. In this work, we propose a highly ordered porous electrolyte additive derived from SSZ-13 for high-rate all-solid-state lithium metal batteries. The nanoporous adsorption effect provided by the highly ordered porous nanoparticles in the poly(ethylene oxide) (PEO) electrolyte is found to significantly improve the Li+ conductivity (1.91 × 10–3 S cm–1 at 60 °C, 4.43 × 10–5 S cm–1 at 20 °C) and widen the electrochemical stability window to 4.7 V vs Li+/Li. Meanwhile, the designed PEO-based electrolyte demonstrates enhanced stability with the lithium metal anode. Through systematically increasing Li+ diffusion, widening the electrochemical stability window, and enhancing the interfacial stability of the SSZ-composite electrolyte (CPE) electrolyte, the LiFePO4/SS...

Two-dimensional (2D) layered transition-metal dichalcogenides (LTMDs) display various crystal phases with distinct symmetries, structures, and physical properties. Exploring and designing different structural phases in two dimensions could provide an avenue for switching material properties, aiming at practical applications for potential fields. Here we demonstrate a conceptually designed approach to narrow the band gap of MoSe2 and obtain a conductive red MoSe2 nanosheet. By introducing the high valence state of Mo species and constructing the Mo–O bonding on the surface of the MoSe2 nanosheets, the electronic properties can be modified and the conductivity is accordingly improved, an effect that significantly improves their lithium storage capacity and high-rate capability. We anticipate that the exploration of the conductive red MoSe2 with tunable band gap could help us unlock more potential crystal structures of LTMD-based and even other 2D materials for further applications.

This paper reports the levitation of micro-organisms in the sheath of radio-frequency (RF) plasma. Based on simple force-balance calculations, the required electric field for the levitation of micro-organisms has been estimated. It is predicted that micro-organisms could levitate at the periphery of the sheath. Experimental results demonstrate the levitation of two species of bacillus micro-organisms Escherichia coli (E. coli) and Klebsiella pneumoniae in an RF plasma. The almost monodiverse Klebsiella pneumoniae levitating in the RF plasma formed an ordered state similar to a 2-D Coulomb crystal. Diverse E. coli particles demonstrate the tendency that the levitating height of micro-organisms decreases as the radius of particles increases. Levitating micro-organisms in plasmas can be referred as dusty plasmas.

Owing to its high theoretical capacity and energy density, lithium sulfur battery represents one of the most promising candidates for future energy storage. However, the dissolution of polysulfide in the electrodes results in shuttle effect and rapid fading of capacity, which impedes practical application of lithium sulfur battery. To inhibit the shuttle effect, in this work, an integrated, highly conductive metal-organic-framework-derived porous nitrogen-carbon-cobalt (N-C-Co) interlayer is designed and prepared to suppress polysulfides lost in electrolyte. Owing to the novel MOFs precursor, N-C-Co composite possesses hierarchical pores, pyridinic and pyrrolic nitrogen groups. This coating interlayer acts effectively through three aspects: as a physical blocking layer to prevent most polysulfides from dissolving out of the cathode, physical and chemical adsorption to confine free polysulfides in the electrolyte, and a second pseudo-upper current collector to enhance the utilization of sulfur. As a result, the improvement of battery performance is achieved by the well-designed interlayer. The initial discharge capacity of composite cathode with the interlayer is 1216.9 mAh g−1 at 1C and can retain capacity of 660.3 mAh g−1 after 250 cycles at the sulfur loading of 1.5 mg cm−2. At the same time, the Coulombic efficiency maintains above 99% during cycling, demonstrating an effective inhibition of the shuttle effect. Even at a high sulfur mass loading of 5.2 mg cm−2, the battery can still deliver 678.8 mAh g−1 after 50 cycles and an areal discharge capacity is of above 3.53 mAh cm−2.

Owing to the high interfacial resistance between a solid electrolyte and sodium metal anode, the development of solid-state sodium batteries is greatly limited. In this work, the introduction of the coating layer composed of micro-sized and cotton-cloth-derived disordered carbon tubes (DCTs) on the surface of the β′′-Al2O3 solid electrolyte (BASE) reduces the interfacial resistance. Better wetting of the DCT modified BASE by sodium results in uniform and rapid Na ion transport across the interface, which significantly reduces the interfacial resistance from 750 Ω cm−2 to 150 Ω cm−2 and presents stable Na stripping/plating profiles at a temperature of 58 °C. Solid-state sodium batteries with a sodium anode, DCT-BASE, and Na3V2(PO4)3 (NVP) gel composite cathode are successfully operated at 58 °C, and deliver good cycling performance and high efficiency. In addition, the self-supported DCT electrode material is proved to have reversible, stable, and rapid Na ion insertion/extraction ability in NIBs.

Nickel foam supported mesoporous FeCo 2 O 4 nanosheets (FCO-NSs-Ni) are synthesized by a simple hydrothermal method, with a subsequent annealing process at a rather low temperature. The three dimensional microstructure, crystal phase and electrochemical performance of the as-prepared FeCo 2 O 4 were investigated systematically. The results show that this material is composed of highly mesoporous nanosheet clusters with large specific surface area. The FCO-NSs-Ni as anode material for sodium ion battery maintains a discharge capacity of 422 mA h g −1 with a coulombic efficiency of 95% after 100 cycles at a current density of 50 mA g −1 . Even at higher current densities of 100 mA g −1 , it still remains a reversible capacity of 338 mA h g −1 after 300 cycles. This FCO-NSs-Ni could be considered as a promising candidate for anode material of sodium-ion batteries.

Proton-conducting reversible solid oxide cells (PC-RSOCs) have attracted much attention for their advantages of working as energy storage devices. In this study, orthorhombic-perovskite structure BaCe0.8−xZr0.2InxO3−δ (x = 0, 0.1, 0.2, 0.3, 0.4) materials have been synthesized. The effect of different indium doping contents on the stability and electrical properties has been investigated. Experimental results reveal that the BaCe0.5Zr0.2In0.3O3−δ possesses the highest proton conductivity with desirable density. Besides, the stability of BaCe0.5Zr0.2In0.3O3−δ is obviously improved in moist air (20 vol% H2O) atmosphere. Anode-supported PC-RSOC with BaCe0.5Zr0.2In0.3O3−δ membrane as an electrolyte displays a maximum power density of 151 mW·cm−2 at 700 °C in solid oxide fuel cell (SOFC) mode. Meanwhile, the PC-RSOC with BaCe0.5Zr0.2In0.3O3−δ electrolyte membrane in solid oxide electrolysis cell (SOEC) mode can also manifest high current density of −729 mA cm−2 at 700 °C with an applied voltage of 1.5 V, and maintains a stable current density of around −124 mA·cm−2 at 700 °C with an applied voltage of 1.1 V for more than 60 h. These encouraging results suggest the potential application of BaCe0.5Zr0.2In0.3O3−δ as electrolyte material for intermediate-temperature PC-RSOCs.

The combination of structure designs at the microscopic and macroscopic level can efficiently enable electrode materials with greatly enhanced lithium and sodium storage. In this paper, the construction of Ni2P/NiS0.66 heterostructures and their assembly into a superstructure at the nanoscale were successfully achieved by a facile and effective strategy. In the obtained superstructure, the Ni2P/NiS0.66 heterostructures are homogeneously coated with ultrathin carbon layers (HT-NPS@C) and, at the same time, assembled into a yolk–shell nanosphere. Upon evaluation as the anode materials for Li-ion batteries, the HT-NPS@C delivers a high reversible capacity of 430 mA h g–1 after 200 cycles at 200 mA g–1 and ultrastable cyclability with negligible capacity loss over 500 cycles. Furthermore, the coin-type full cell with the LiNi1/3Co1/3Mn1/3O2 (LNCMO) cathode and HT-NPS@C anode deliver a high specific capacity of 323.5 mA h g–1 after 50 cycles at 0.3 A g–1. Apart from an excellent performance as promising anode ...

High temperature sodium batteries with inorganic electrolytes are attracting increasing attention due to their high thermal stability, reliability, long-cycle life and safety. Despite the intensive investigation of Na-NiCl 2 batteries during last decades, designing a stable conducting network in the cathode is still challenging but desirable. In this work, a new cathode structure composed of Ni nanowires with an effective electron conducting network is proposed for planar sodium–nickel chloride batteries. During the first stage of charge, Ni nanowires reacted with Cl ion to form NiCl 2 on the surface and the excessive Ni nanowires inside can serve as conducting framework to facilitate the fast electron transport. As expected, the metal nanowires show a high specific capacity of 130 mA h g −1 (∼14 mAh cm −2 ) at 0.05 C after 100 cycles. Meanwhile, the batteries show stable cycling performance at 0.05 C with a high cut-off energy density of 360 W h kg −1 , much higher than the traditional tubular sodium-nickel chloride batteries (∼100 Wh kg −1 ). Scanning electron microscope (SEM) images of the cathode after long cycling reveal the ultra-slow growth of Ni particles, confirming the excellent stability of the prepared nanowires cathode.

The efficient reversible formation of discharge products for Li-O 2 batteries is still challenging. Meanwhile, the question of the nature of the discharge products and their decomposition mechanism are still remain. Implanting oxygen vacancies on the metal oxides can create negative-charge surface to provide strong adsorption of active oxygen and at the same time, the exposed metal sites can serve as an efficient substrate for decomposed reaction of discharge products. In this work, we apply the graphene-like MoO 3 ultrathin nanosheets as a matrix. By controlling the reduction time, the MoO 3 nanosheets with different concentration of oxygen vacancy are obtained. Experimental results reveal that the MoO 3 nanosheets with the high-concentration oxygen vacancies can significantly decrease the overpotential and get enhanced electrochemical response, namely, a low overpotential of ~0.5 V can be delivered with ultra-stable cycles (over 60 cycles). Moreover, the Li-O 2 batteries demonstrate an interesting four-step discharge and charge process. X-ray photoelectron spectroscopy, X-ray diffraction, transmission electron microscopy and electron energy-loss spectroscopy analyses are carried out for the four typical states of the cathode to reveal the reaction mechanism for the unique electrochemical behavior.

The direct lattice strain, either distortion, compressive, or tensile, can efficiently alter the intrinsic electrocatalytic property of the catalysts. In this work, we report a novel and effective strategy to distort the lattice structure by constructing a metastable MoSSe solid solution and thus, tune its catalytic activity for the Li–O2 batteries. The lattice distortion structure with inequivalent interplanar spacing between the same crystals plane were directly observed in individual MoSSe nanosheets with transmission electron microscopy and aberration-corrected transmission electron microscopy. In addition, in situ transmission electron microscopy analysis revealed the fast Li+ diffusion across the whole metastable structure. As expected, when evaluated as oxygen electrode for deep-cycle Li–O2 batteries, the metastable MoSSe solid solution deliver a high specific capacity of ∼730 mA h g–1 with stable discharge–charge overpotentials (0.17/0.49 V) over 30 cycles.

The lithium-sulfur battery is one of the most prospective chemistries in secondary energy storage field due to its high energy density and high theoretical capacity. However, the dissolution of polysulfides in liquid electrolytes causes the shuttle effect, and the rapid decay of lithium sulfur battery has greatly hindered its practical application. Herein, combination of sulfonated reduced graphene oxide (SRGO) interlayer on the separator is adopted to suppress the shuttle effect. We speculate that this SRGO layer plays two roles: physically blocking the migration of polysulfide as ion selective layer and anchoring lithium polysulfide by the electronegative sulfonic group. Lewis acid-base theory and density functional theory (DFT) calculations indicate that sulfonic groups have a strong tendency to interact with lithium ions in the lithium polysulfide. Hence, the synergic effect involved by the sulfonic group contributes to the enhancement of the battery performance. Furthermore, the uniformly distributed sulfonic groups working as active sites which could induce the uniform distribution of sulfur, alleviating the excessive growth of sulfur and enhancing the utilization of active sulfur. With this interlayer, the prototype battery exhibits a high reversible discharge capacity of more than 1300 mAh g

Silicon has been extensively studied as an anode material in lithium-ion batteries due to its extremely high theoretical specific capacity of 3578 mAh/g (assuming Li15Si4 as intermediate product). However, silicon undergoes huge volume variations during repeated discharge and charge, leading to poor electrode mechanical integrity, continual electrolyte decomposition and fast capacity decay. Developing high strength binders in silicon anodes have been considered as an efficient pathway to alleviate various capacity decay pathways. Currently, lithiated poly acrylic acid (LiPAA) is mostly used as the binder for silicon electrodes due to its strong binding capability and (electro)chemical compatibility with Si and electrolyte. However, cracks at the electrode level can still be observed for the cycled electrodes, which suggests that a stronger binder is required to mitigate volume expansion of Si electrode and hold the particles together. Herein we study the polyimide (PI) materials as the binders for Si anode in an attempt to achieve stable cycling performance. With PI binder, the silicon electrode exhibits a higher tensile strength than that of conventional PAA binder. The strong adhesion of the PI binder suppresses the structural collapse of the Si negative electrode during lithiation/delithiation, enabling high capacity retention and stable cycle life. However, the PI crosslinking process requires high temperature and inert atmosphere, which is a challenge for its practical application. In this work, we explore various PI crosslinking conditions and their effects on electrochemical performance. This work offers us an alternative binder material with high tensile strength for the Si electrode. Acknowledgement We gratefully acknowledge the support from the U.S. Department of Energy's Vehicle Technologies Office. This work is conducted under the Cell Analysis, Modeling, and Prototyping (CAMP) Facility at Argonne National Laboratory. Argonne National Laboratory is operated for DOE office of Science by UChicago Argonne, LLC, under contract number DE-AC02-06CH11357.

This research aimed to clarify the physical effects of plasma on microorganisms levitated in radio-frequency (RF) plasma and to develop a technology for classifying and confining microorganisms by controlling their behavior when levitated. In the experiment, multiple types of microorganisms were injected into the RF plasma one by one, and their behavior was analyzed. An external electric field was applied to the plasma. The experimental results revealed that the behavior of the levitated microorganisms differs depending on the species and the magnitude of RF discharge power.

The electrochemical performance of rechargeable lithium–oxygen (Li–O2) batteries relies on the catalysts used in the cathode to a great extent. Herein, a series of CuxCo3−xO4 nanorods with different Cu2+ concentrations was prepared by a convenient hydrothermal method. The corresponding structures and electrochemistries were further characterized in order to reveal the composition effect of catalyst on catalytic activity. Experimental characterization and theoretical calculations indicate that more Cu2+ occupying Co2+ positions and dispersing on the catalyst surface has an enhanced catalytic activity in terms of higher capacity, lower overpotential and better reversibility. This implies that suitable charge transfer from Li2O2 to the catalyst plays an important role in improving the electrochemical performance of Li–O2 batteries. The present study is helpful for designing a highly active catalyst by tuning the composition of the catalyst surface.

The development of high capacity lithium–sulfur (Li–S) batteries is hampered by both the shuttle effect of polysulfides and low sulfur areal loading problems. To inhibit the shuttle effect, a polysulfide adsorptive polymer polyethylenimine (PEI) is covalently bonded with reduced graphene oxide (rGO) in a one-step hydrothermal reaction. Meanwhile, multi-walled carbon nanotubes (MWCNTs) are simultaneously interweaved with rGO. The resultant PEI–rGO–MWCNT aerogel (PEI–GC) provides ample chemisorption domains of amine groups and abundant electrical contact sites. Density functional theory (DFT) calculations prove a binding energy of 2.43 eV between PEI and polysulfide. The PEI–GC cell achieved a high capacity of 933 mA h g−1 for the 500th cycle at 1C, stable rate performance up to 10C, and low self-discharge rate. The covalent bond between PEI and rGO experiences no degradation during the 500 cycles. Moreover, PEI–GC achieved excellent cycling performance at a high sulfur loading of up to 18 mg cm−2.

Sodium carboxymethyl cellulose-styrene butadiene rubber (CMC-SBR), sodium alginate (SA) and LA132 are utilized as the polymer binders for the cathodes of Li-S batteries to study their dispersion mechanism on the cathode materials and the consequent influence on the performance of Li-S batteries. Zeta potential tests, differential scanning calorimetry analysis and calculations of the rotational barriers of the links of the polymer chains by General Atomic and Molecular Electronic Structure System (GAMESS) reveal that higher charge densities and better chain flexibility of the binders promise the dispersion of the downsized cathode materials. LA132 is found to have optimal characteristic for dispersing and stabilizing the cathode materials in aqueous environment. The cycling performance and SEM images of the cathodes demonstrate that cathodes with higher dispersion degree achieve higher discharge capacities. The electrochemical impedance spectroscopy (EIS) results further support that better dispersed cathodes have lower impedance resulting from their well established conducting frameworks.

Natural period of architectural structure have been longer to be high-rise in recent years. Tuned Mass Damper (TMD) is applied for the structural response reduction in such a long period structure. In general since there are a lot of design cases using a guide rail for linear motion guide of the mass in TMD, the friction coefficient in assembled TMD becomes almost from 3/1000 to 5/1000. The friction coefficient leads an important problem in view point of performance design for long period structures because of that the friction force becomes a large compared with starting inertia force. In this study, new type TMD with air pressure floating technique has been examined to reduce a friction force for starting inertia force, and to set 0.01 m/s2 in starting acceleration as a performance target. This paper shows the evaluation results for fundamental performance from static loading test and shaking table test.

Sodium–oxygen batteries are an attractive alternative for electrical energy storage applications because of their high-energy density and low cost. As a common challenge for all air-based battery systems, Na–O2 batteries also suffer from inefficient reversible formation of discharge products and poor cycling performance. Here, we report the design and synthesis of a binder-free air electrode composed of three-dimensional (3D) nitrogen-doped graphene aerogels (N-GAs). In this design, nitrogen-doped graphene aerogels grow directly on the Ni foam (3D N-GA@Ni) with a well-preserved interconnected 3D architecture. The Na–O2 cell with the 3D N-GA electrode is capable of large capacity (10 905 mA h gcarbon−1 at a current density of 100 mA gcarbon−1), long cycle life (over 100 cycles at 100 mA g−1 with a specific capacity limit of 500 mA h gcarbon−1) and high rate performance (over 50 cycles at 300 mA gcarbon−1). These properties are mainly attributed to the active N-group, which controls the uniform deposition of discharge products at the nanoscale and provides active sites for decreasing overpotential. This encouraging performance also offers a brand new approach to improve the electrochemical performance of Na–O2 batteries and other metal–air batteries.

Developing highly active and cost-effective catalysts for Li–O2 batteries with high capacity, long cycle life and good rate performance is still challenging. In this work, a simple and efficient strategy is developed for the synthesis of MnOx spheres with a core–multishell structure. The spheres are assembled by ultrafine manganese oxide nanocrystals containing mixed-valent MnII, MnIII, and MnIV species. The Li–O2 batteries with MnOx sphere electrodes can deliver high discharge capacity, long-life cycling and excellent rate performance, namely, a specific capacity as large as 9709 mA h gcarbon−1 is delivered at 100 mA gcarbon−1 and maintained over 320 cycles at a limited capacity of 1000 mA h gcarbon−1. Even at a high capacity (2000 mA h gcarbon−1) with a high current density of 200 mA gcarbon−1, the batteries can still endure more than 120 cycles. During the long cycling, the batteries show ultra-stable electrochemical performance with a high discharge potential (2.8–2.9 V) and low charge voltage (3.7–3.8 V). High-resolution transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy analyses for cycled mixed-valent MnOx electrodes are used to reveal the electrochemical mechanism.

Macroscopic two-dimensional (2D) images of flowing weakly magnetized lithium (Li+) ion beams are systematically presented. When the beam density approaches the Brillouin density limit, the 2D shape of the flowing Li+ ion beam deforms gradually. Also, the images clearly show not only the m = 1 shift mode but also higher modes of the flowing Li+ ion beams. These observed modes are analyzed by using a Fourier transform method.

We have conducted an experiment in which pure lithium-ion and electron plasmas are mixed by simultaneously confining the plasmas in a nested-penning trap to experimentally explore a two-fluid plasma state. Preliminary data show that the Li+ ion plasma, after plasma mixing, is divided into small circle- and crescent-shaped parts over time. Conversely, the e− plasma after plasma mixing shifts or expands radially.

Graphene nanosheets loaded with highly dispersed platinum nanoparticles (Pt@GNSs) are prepared by a simple and effective hydrothermal method. The Pt@GNS as an air cathode material exhibits a very high initial discharge capacity of 7574 mA h−1 g−1 at a current density of 0.1 mA cm−2 and delivers a stable cycling performance. The electrocatalytic characteristics of Pt on the Na–O2 cell have been investigated for the first time.

Magnesium alloys have received considerable attention because of their lightweight and recyclability. AM-type and AZ-type Mg-Al alloys have been used for industrial products widely, particularly for AM-type alloys because of the better toughness and impact absorption properties than AZ-type alloys. However, there is little report about the effect of casting method on age-hardening behavior and microstructure of AM-type alloys. The purpose of this study is to investigate the difference of the age-hardening behavior and microstructures of three AM-type alloys cast with steel, copper and sand molds using hardness test and scanning electron microscopy (SEM) observation. Furthermore, the effect of Al content is also investigated in this study using three alloys of AM30 (3%Al), AM60 (6%Al) and AM90 (9%Al).

AM60 magnesium alloy castings gave the solution treatment at 688K for 86.4ks. After that, aging treatment was carried out at three temperatures of 473, 498 and 523K. The age hardening curve obtained, hardness of all the specimens in the condition of peak aging was increased by decreasing the aging temperature. In the condition of long aging time, a cellular precipitation grows up from grain boundary to crystal grain. Fine cellular precipitation and intergranular precipitation obviously occurs at the lower aging temperature.

The purposes of this study were to evaluate the effects of different degrees of water contamination on the shear bond strength of orthodontic brackets bonded to dental enamel with a moisture-insensitive primer (MIP) adhesive system and to compare the modes of bracket/adhesive failure. A total of 68 human premolars were divided into four groups by primers and enamel surface conditions (desiccated, blot dry, and overwet). In group I, the hydrophobic Transbond XT primer adhesive system was used under desiccated conditions for bonding the brackets; in group II, the hydrophilic Transbond MIP adhesive system was used under desiccated conditions; in group III, the hydrophilic Transbond MIP adhesive system was used under blot dry conditions; and in group IV, the hydrophilic Transbond MIP adhesive system was used under overwet conditions. Shear bond strength was measured with a universal testing machine, and the mode of bracket/adhesive failure was determined according to the adhesive remnant index. The mean shear bond strengths were not significantly different among groups I, II, and III, and were higher than the clinically required range of 6 to 8 MPa. The mean shear bond strength achieved in group IV was significantly lower than that achieved in groups I, II, and III, and also lower than the clinically required values. Bond failure occurred at the enamel-adhesive interface more frequently in group IV than in groups I and III. To achieve clinically sufficient bond strengths with the hydrophilic MIP adhesive system, excess water should be blotted from the water-contaminated enamel surface.

Constructing three-dimensional (3D) architecture with oriented configurations by two-dimensional nanobuilding blocks is highly challenging but desirable for practical applications. The well-oriented open structure can facilitate storage and efficient transport of ion, electron, and mass for high-performance energy technologies. Using MoS2 as an example, we present a facile and effective hydrothermal method to synthesize 3D radially oriented MoS2 nanospheres. The nanosheets in the MoS2 nanospheres are found to have less than five layers with an expanded (002) plane, which facilitates storage and efficient transport of ion, electron, and mass. When evaluated as anode materials for rechargeable Li-ion batteries, the MoS2 nanospheres show an outstanding performance; namely, a specific capacity as large as 1009.2 mA h g(-1) is delivered at 500 mA g(-1) even after 500 deep charge/discharge cycles. Apart from promising the lithium-ion battery anode, this 3D radially oriented MoS2 nanospheres also show high activity and stability for the hydrogen evolution reaction.

Diamond surface reforming was performed using silane coupling reagents. Oxidation reaction with inorganic acid was utilized as the pretreatment of the diamond substrate. After the silane coupling reaction process, new peaks assigned to the silane coupling reagent appeared in the IR spectra. Moreover, the diamond surface property changed from hydrophilic to hydrophobic with the treatment of n-octyltrimethoxysilane. From the results of this study, it was confirmed that silane coupling reagents are effective for diamond surface reforming.

Diamond surface reforming was carried out using various silane coupling reagents (n-octyltrimethoxysilane, 3-aminopropyltrimethoxysilane, or 3-mercaptopropyltrimethoxysilane). In order to introduce the O-H group, which reacts with the methoxy group in the silane coupling reagents, on the diamond surface, hydrogenated diamond surfaces were treated with mineral acids (H2SO4, H2SO4+HNO3, or aqua regia). The diamond powders treated with H2SO4 or H2SO4+HNO3 were utilized as the diamond substrate for the reaction with the silane coupling reagents. After the treatment with the silane coupling reagents, peaks assigned to the chemical bonds in the silane coupling reagents appeared in the IR spectrum of the diamond powders. Moreover, these peaks remained even after washing 3 times with organic solvents. The oxidized diamond surface was changed from hydrophilic to hydrophobic upon treatment with n-octyltrimethoxysilane. From the results of this study, it was confirmed that the silane coupling reagent is effective for the surface reforming of diamond treated with mineral acid.

As the finalization of a hydrogen experiment towards the deuterium phase, the exploration of the best performance of hydrogen plasma was intensively performed in the large helical device. High ion and electron temperatures, Ti and Te, of more than 6 keV were simultaneously achieved by superimposing high-power electron cyclotron resonance heating onneutral beam injection (NBI) heated plasma. Although flattening of the ion temperature profile in the core region was observed during the discharges, one could avoid degradation by increasing the electron density. Another key parameter to present plasma performance is an averaged beta value $\left\langle \beta \right\rangle $ . The high $\left\langle \beta \right\rangle $ regime around 4% was extended to an order of magnitude lower than the earlier collisional regime. Impurity behaviour in hydrogen discharges with NBI heating was also classified with a wide range of edge plasma parameters. The existence of a no impurity accumulation regime, where the high performance plasma is maintained with high power heating >10 MW, was identified. Wide parameter scan experiments suggest that the toroidal rotation and the turbulence are the candidates for expelling impurities from the core region.

Nitrogen ions were impinged during the molecular beam epitaxial growth of GaAs at 550°C, varying its acceleration energy in the range from 100 eV to 10 keV. No photoluminescence (PL) emissions were observed in as-grown condition when ion acceleration energy becomes higher than 500 eV. After high-temperature annealing at 750°C, structural defects were removed and incorporated nitrogen atoms became optically active. PL emissions that relate to isoelectronic impurity and dilute GaAsN alloys were observed with an ion acceleration energy of 10 keV.

β-FeSi 2 has attracted increasing attention as a promising material for optoelectronic and thermoelectronic devices due to a high optical absorption coefficient (α) of about 10 5 cm −1 near 1.0 eV and its chemical stability at higher temperatures. For the future practical use of this material in devices, the control of each electrical conductivity type and the improvement of the material quality are highly required. Although unintentionally doped β-FeSi 2 layers formed on n-type Si(1 0 0) by the conventional electron-beam deposition (EBD) have typically shown n-type conductivity, the p-type β-FeSi 2 layers were formed by the introduction of Mn impurity using ion-implantation at room temperature (RT) and subsequent annealing procedures. In this study, we aimed to make p-type β-FeSi 2 by implantation of 55 Mn + ions into EBD-grown n-type β-FeSi 2 layers/n-Si, where 55 Mn + ions were implanted at two different temperatures ( T sub ) of RT and 250°C using an energy and a dose of 300 keV and 2.68 × 10 15 cm −2 , respectively. Their optical and electrical properties, which ought to be affected by implantation and annealing temperatures ( T a2 ), were investigated by Raman scattering, optical transmittance, reflectance and van der Pauw measurements. The results showed that the 55 Mn + doping with T sub =RT and higher thermal annealing at T a2 =900°C produced p-type layers of good quality with maximum hole mobility of 454.5 cm 2 /Vs at about 65 K.

Nitrogen (N) ions were impinged during the epitaxial growth of GaAs using combined ion beam and molecular beam epitaxy (CIBMBE) method. Low-temperature photoluminescence measurements showed that incorporated nitrogen ([N] 18 cm −3 ) is optically active with a substrate temperature of 550°C and a N + ion acceleration energy of 100 eV. For higher [N] of ∼2×10 18 cm −3 , N-related emissions can be found after high temperature (650–850°C) annealing. We discuss the annealing effects and also the novel emissions found after annealing at high temperature (750°C) with a [N] of ∼1×10 19 cm −3 .

The standard gas mixture used for RPCs contains /spl sim/60% Ar, /spl sim/40% isoC/sub 4/H/sub 10/ and several percent of CF/sub 3/Br (Haron1301) as quenching agent. CF/sub 3/Br is known to destroy the atmospheric ozone layer. For this reason its use is discouraged, and prohibited by law in the near future. C/sub 2/F/sub 6/ (FC116) and C/sub 2/H/sub 2/F/sub 4/ (HFC134A) seem to be an ideal candidate from an environment point of view since its ozone depletion potential is very low. We present the results of a test performance on RPC (glass) operating with non-ozone depletion freon gas and butane-silver.

Longitudinal and transverse wave velocities, five kinds of elastic parameters (Young’s, shear and bulk moduli, Lame parameter, Poisson’s ratio), Debye temperature, and dilational and shear internal frictions for fused quartz were simultaneously measured over the temperature range from 73 to 400 K, using the ultrasonic pulse wave with frequency of 7.7 MHz. Large increase in Young’s and bulk moduli and small increase in shear modulus and Lame parameter suggest enhancement of rigidity for KI mode on heating. This would be explained by quasi-crystallization which is associated with a lateral motion of oxygen atoms and the resulting relief of macroscopic strains. The 99 and 137 K peaks and 360 K one in shear friction are probably related to dielectric loss peaks arising from Al3+–Na+ and Al3+–K+ substitutional–interstitial paired defects and to β1/β2-tridymite phase transition, respectively.