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Developing new electrode materials with a high specific capacity for excellent lithium-ion storage properties is very desirable. The MnCO3/Mn3O4 nanoparticles with uniform size (about 50 nm) and shape which are wrapped with graphene have been successfully synthesized via the one-step method for anode material of lithium-ion batteries. The as-prepared graphene-wrapped MnCO3/Mn3O4 nanocomposite exhibits remarkable electrochemical performance, including high reversible specific capacity, outstanding cycling stability, and excellent rate capability in comparison with the bare MnCO3 and MnCO3/Mn3O4 nanocomposite. This is because the synergistic effect of MnCO3 and Mn3O4 nanoparticles and graphene nanosheets act as both electron conductors and volume buffer layers. From the scanning electron microscopy (SEM) analysis, we confirmed that the morphology and structure of the composite are preserved after 200 cycles. This further confirms that graphene-wrapped MnCO3/Mn3O4 nanocomposite acts as a stable template for reversible lithium-ion intercalation/deintercalation.

Cu/Al clad sheets with a 304 stainless steel foil (SUS304) interlayer are successfully fabricated by the powder-in-tube method. The influence of SUS304 thickness on the interfacial structure, elemental diffusion, and peeling strength of the clad sheets is studied. Experimental results indicate that the initial Cu/Al interface is partially transformed into a Cu/SUS304/Al interface after introducing the SUS304 interlayer. The proportion of SUS304 fragments at the bonding interface is shown to increase with thickness of the SUS304 interlayer. Differences in deformability between SUS304 interlayer and Cu/Al matrix promote the occurrence of shear deformation at the bonding interface via the cladding process, enhancing atomic diffusion at the Cu/SUS304/Al interface. Peeling tests reveal that interfacial cracks in clad sheets with an SUS304 interlayer propagate along the Cu/SUS304 and Cu/Al interfaces. Under combined effects of interfacial transfer and large shear strain, the interfacial strength of clad sheets is apparently improved. Clad sheets with the thickest SUS304 interlayer (30 μm) exhibit highest peeling strength (30.9 N/mm), demonstrating 73.6% improvement over clad sheets without an interlayer. These findings provide novel insights into the innovative design of clad sheets possessing extraordinary interfacial strength.

Determining atomic structure of intercalated metallic layer under graphene is a hot-topic due to the potential applications in electronic engineering. In this study, Pb-intercalated graphene (PbG) is fabricated on SiC substrate and the atomic structure and electronic properties of the intercalated Pb atoms underneath graphene are investigated by scanning tunneling microscopy/spectroscopy (STM/STS). As the crystal facet of intercalated Pb atoms can be arranged in (111) (unit cell, 0.35 nm × 0.35 nm) and (110) (unit cell, 0.61 nm × 0.35 nm), mottled moire pattern (period, 2.5 nm) and striated moire pattern (period, 2.1 nm) are formed. Atomic arrangement of the intercalated Pb is sensitive to tip scanning resulting in the conversion of the two moire patterns. Nevertheless, the crystal orientation of moire patterns is always aligned with zigzag direction of graphene. As revealed by STS, PbG performs the similar electronic states to those of free-standing graphene due to the shielding effects of Pb intercalation. The crystallographic relationship between graphene and Pb atoms is also confirmed by density functional theory (DFT) calculations. The study provides crucial for understanding the structure of intercalated Pb atoms underneath a graphene layer, which may enable the development of new 2D materials capped by graphene.

In this investigation, ultrasonic-assisted soldering at 260 °C in air produced high strength and high melting point Cu connections in 60 s using Ni foam reinforced Sn composite solder. Systematically examined were the microstructure, grain morphology, and shear strength of connections made with various porosities of Ni foam composite solders. Results shown that Ni foams as strengthening phases could reinforce Sn solder effectively. The addition of Ni foam accelerated the metallurgical reaction due to great amount of liquid/solid interfaces, and refined the intermetallic compounds (IMCs) grains by ultrasonic cavitation. The joints had different IMCs by using Ni foam with different porosity. Layered (Cu,Ni)

A series of Na3Ba2-xB6O12F:xEu3+ (x = 0.03, 0.05, 0.08, 0.10, 0.13, 0.16, 0.17, 0.19, 0.20 and 0.22) phosphors were prepared by the high temperature solid state reaction method. The single crystal-phase Na3Ba2B6O12F of the Na3Ba2-xB6O12F:xEu3+ sample was confirmed by X-ray powder diffraction measurement. The optical properties are evaluated by photoluminescence excitation and emission spectra, CIE chromaticity coordinate and decay curve. Na3Ba2-xB6O12F:xEu3+ phosphors present the red emitting color under the excitation of near-UV light around 395 nm. Investigation of Eu3+ content dependent emission spectra indicates that x = 0.19 is the optimum doping content of Eu3+ ions in the Na3Ba2B6O12F host. Moreover, the critical distance and the concentration quenching mechanism were also investigated. The absolute luminescence quantum efficiency and the decay time of Na3Ba1.81B6O12F: 0.19Eu3+ sample were reported.

Echinochloa crus-galli L., a notorious weed in rice paddy fields, is usually kept under control by mefenacet application at the pre-emergence or early post-emergence stage. Due to continuous and repeated usage, E. crus-galli is developing resistance to mefenacet in China. Two putative resistant and one susceptible E. crus-galli populations were collected from paddy fields in Jiangsu Province to characterize their herbicide resistance. Compared with the susceptible population, the two mefenacet-resistant populations had 2.8- and 4.1-times greater pre-emergence resistance, and 10- and 6.8-times greater early post-emergence resistance to mefenacet. These mefenacet-resistant E. crus-galli populations also exhibited cross- or multiple-resistance to acetochlor, pyraclonil, imazamox, and quinclorac. However, when the glutathione S-transferase (GST) inhibitor 4-chloro-7-nitrobenzoxadiazole (NBD-Cl) was applied prior to post-emergence treatment, mefenacet resistance levels were reduced in both populations. Additionally, GST activity in vivo in one resistant population was much higher than the susceptible population after mefenacet application. The very long chain fatty acid elongases (VLCFAEs) from both mefenacet-resistant populations required much higher mefenacet concentration to inhibit their activity. The reduced sensitivity of VLCFAEs to mefenacet indicates the presence of a target-site resistance mechanism and induction of high GST activity may provide additional contribution to E. crus-galli mefenacet resistance through a non-target-site mechanism.

AA1050/AA5052 multilayer laminate sheets were fabricated by accumulative roll bonding (ARB) and cryorolling (CR). The ultimate tensile strength (UTS) of the laminate sheets produced by combining ARB and CR increased up to 18.4% compared to that by five ARB passes. Necking and fracture occurred in the hard layer after the fourth ARB pass. In contrast, the hard layer remained continuous and relatively straight during CR, which suggested that CR can delay the onset of necking and fracture. TEM results showed that CR can not only refine grain size but also significantly improve interfacial bonding quality. CR can accumulate higher dislocation density. Therefore, the laminate sheets prepared by the combination of ARB and CR obtained better mechanical properties than that by five ARB passes.

Revealing the detailed mechanism of metal intercalation on epitaxial graphene on SiC (EG/SiC) is difficult due to the complicacy and randomness of thermal decomposition of SiC substrate. In this context, the fabrication and mechanism of Pb-intercalated graphene (PbG) produced on SiC are investigated by scanning tunneling microscopy (STM) and X-ray Photoelectron Spectroscopy (XPS). It is reported that Pb intercalation prefers to happen at the interface between buffer layer and SiC substrate. Pb atoms penetrate into buffer layer through point defects on buffer layer or graphene edges during annealing, making the buffer layer transferred into an additional graphene layer. PbG regions are mainly exhibited as regular ordered moire pattern because of the mismatch between Pb atoms and graphene layer. Some irregular PbG regions with scattered moire pattern are also formed due to the insufficient intercalation of Pb atoms underneath. In addition, the intercalated Pb atoms arrange as two dimensional (2D) ultrathin structure underneath the newly formed PbG, and the thickness of PbG layer will increase by one after Pb intercalation. This study benefits to the modification of electronic properties of graphene on SiC, promoting the development of new 2D materials protected by graphene layer.

Gradient-structured Zr sheets were fabricated by cyclic skin-pass cryorolling and cyclic skin-pass rolling. The mechanical properties and microstructural evolution of the gradient-structured Zr after rolling and annealing were investigated. The results indicated that the cyclic skin-pass cryorolled samples exhibited higher tensile strengths (σb = 557 MPa) and slightly lower fracture elongations (eu = 17.1%) than the cyclic skin-pass rolled samples due to high dislocation storage. After annealing at 150 °C–450 °C for 1 h, high-resolution transmission electron microscopy results showed that the ultrafine-grained layer of the cyclic skin-pass cryorolled samples exhibited better thermal stability, which was attributed to the formation of nanoscale twins and incomplete recovery of dislocations.

A novel preparation method has been proposed that using electrodeposited copper foil as raw material and then performing asymmetrical rolling and surface morphology modification to improve the corrosion resistance of the copper foil current collector in lithium-ion battery electrolyte for long-term storage. The results of electrochemical experiments show that the corrosion current density of rolled electrodeposited (RE) copper foil is only 10% of that of electrodeposited (ED) copper foil. After RE copper foil is stored in the electrolyte for 100 days, its capacity retention rate is ~91.2%, which is much higher than 75.6% of ED copper foil and 80.8% of rolled copper foil. The fraction of low-Σ CSL boundaries of RE copper foil is 33.6%, which is much higher than 2.2% for rolled copper foil and 8.7% for ED copper foil. The large fraction of low-Σ CSL boundaries and disrupted RHABN in RE copper foil is an effective structure to inhibit corrosion; Asymmetrical rolling and surface morphology modification significantly increase the compressive residual stress and surface roughness of RE copper foil, which can effectively improve the corrosion performance of copper foil. The RE copper foil with modified surface morphology provides a new idea for the next generation of high-performance lithium-ion battery current collector materials.

Chinese sprangletop (Leptochloa chinensis (L.) Nees) is a serious grass weed in rice paddies. In some areas, L. chinensis has become resistant to the herbicide cyhalofop-butyl because of its frequent and extensive use over the past five years. In this study, whole-plant dose-response assays were conducted, and a L. chinensis population (ZHYH) had a 75.8-fold resistance index to cyhalofop-butyl. Molecular analyses revealed that this resistance was attributed to a tryptophan (Trp)-2027-to-cysteine (Cys) substitution in the CT domain of the ACCase gene. To our knowledge, this is the first report revealing the mechanism underlying cyhalofop-butyl resistance in L. chinensis. Furthermore, a derived cleaved amplified polymorphic (dCAPS) assay was developed to rapidly detect the Trp-2027-Cys mutation. Of the 100 ZHYH plants analyzed, 52 were heterozygous mutants and 48 were susceptible homozygous plants. In addition, the cyhalofop-butyl-resistant L. chinensis was cross-resistant to aryloxyphenoxypropionate and phenylpyrazoline herbicides, but not to cyclohexanedione, acetolactate synthase-inhibiting, protoporphyrinogen oxidase, and urea herbicides, and had only slight resistance to the hormonal herbicide quinclorac.

In this contribution, we propose and demonstrate a scalable and reproducible process to fabricate nano-sized functional particles and integrate them in microelectromechanical systems. We use a wet-chemistry approach for nanoparticle synthesis in combination with inkjet printing as a production process for metal oxide based gas sensors. This method enables control over size and shape of the nanoparticles as well as an ordered and reproducible deposition of a monolayer of particles onto arbitrary microstructures. Here we present results obtained using copper oxide nanoparticles as well as their synthesis and material characterization. A total of 14 layers has been produced and the baseline resistivity as well as the gas sensitive response towards oxygen, humidity and nitrogen dioxide of each layer has been determined.

A study based on uniaxial tension tests were conducted in this paper to understand the hot deformation behaviors of TA32 alloy during superplastic deformation at a deformation temperature of 915 °C and an initial strain rate of 6.64×10 −3 s −1 . In the test, the maximum fracture elongation reached 1065%, exhibiting good superplastic deformation ability. Electron back-scattered diffraction (EBSD) was used to analyze and study evolution of microstructures and textures in the process of deformation with the following findings: During tensile deformation, the fraction of low-angle grain boundaries (

A novel method that taking electrodeposited copper foil as a raw material undergoes asynchronous rolling and surface morphology modification at room temperature was proposed, and the rolled electrodeposited (RE) copper foil with excellent mechanical properties and modified surface morphology was obtained to be used as the anode current collector of high-performance lithium-ion batteries. The surface roughness of RE copper foil (Ra = 1.8 μm) is significantly higher than that of the traditional electrodeposited copper foil (Ra = 0.22 μm) when the thickness is 6 μm. The hilly surface morphology of RE copper foil helps to enhance the interfacial adhesion between current collector and active material, which contributes to the reduction of charge transfer resistance and improvement of specific capacity and rate performance. The mechanical properties of RE copper foil are significantly improved after asynchronous rolling. The excellent mechanical properties of RE copper foil current collector can maintain good electrical contact integrity of electrode active material during lithiation-de-lithiation and significantly improve the cycle life. The discharge capacity of RE electrode is maintained at 329.6 mAh g−1 and exhibits 91.1% capacity retention for 200 cycles at 500 mAg−1, which is much higher than the electrodes with electrodeposited and rolled copper foils as the current collector.

The past decade has witnessed great advances in three-dimensional (3-D) medical ultrasound (US) imaging instrumentation. An increasing demand for portable 3-D US equipment is one of the main trends upcoming in the market. In this study, we developed a low cost, portable, sensorless and wireless 3-D US imaging system. A laptop US scanner with a conventional linear probe and a convex probe was used to acquire 2-D US B-scans. A client program was developed and run on the US scanner for capturing the pictures of screen during a freehand scanning without a positional sensor, and then the JPEG compression was applied to the pictures for reducing the image data size. The image data was sent to a remote workstation in real-time through Wi-Fi connection. A neural network model was used to recognize the characters (e.g. imaging depth and probe model information) displayed on the screen of the US scanner. The server on the remote workstation communicated with the US scanner, received raw image data, and finally reconstructed 3-D US images. The positions of the B-scans were obtained by estimating the spacings of B-scan image sequence, which was learned by measuring adaptive speckle decorrelation curves in mechanically collected B-scan frames. The performance of the proposed system has been demonstrated through experiments conducted on a US resolution phantom in vitro as well as human tissues in vivo.

Lithium–Zinc ferrite hollow microspheres (LiZn FHMs) doped with La and Mg were synthesized by Fe + Zn + Fe2O3 + O2 + Li2CO3 reactive system based on self-reactive quenching technology. Influence of La and Mg doping on the surface morphology, phase structure and microwave absorption properties of LiZn FHMs were investigated. The results show that the surface morphology of LiZn FHMs changes little and are still composed of unnoticeable multi-shape crystal grains, whether they are doped or not. The phases are mainly made up of Fe3O4, Fe2O3, Li0.435Zn0.195Fe2.37O4 and Li0.5Fe2.5O4 without doping. The phases remain unchangeable after Mg doping, while LaFeO3 appears in the phase components after La doping. When LiZn ferrites are without doping, their minimum reflectivity at 4 mm is −14 dB at 7.5 GHz, and the effective absorption frequency band less than −10 dB is 6.4–8.6 GHz, with the bandwidth of 2.2 GHz. Compared with that without doping, the minimum reflectivity increases after Mg doping, and the effective absorption frequency band less than −10 dB disappears. After La doping, the minimum reflectivity is −30.2 dB at 6.2 GHz, and the effective absorption frequency band is 4.7–7.7 GHz, with the bandwidth of 3 GHz. It is found from the present investigations that the microwave absorption properties are improved after La doping, and those of LiZn FHMs after Mg doping are reduced.

Therapeutic options for Epstein-Barr virus (EBV)-associated post-transplantation lymphoproliferative diseases (PTLD) are currently limited, accompanying with some off-target toxicities. We previously demonstrated that early recovery of Vδ2+ T cells inversely correlated to EBV reactivation after allogeneic hematopoietic cell transplantation. Studies in vitro and in the mouse models showed the cytotoxic activity of Vδ2+ T cells on EBV-transformed lymphoproliferative cells, but the efficacy was moderate. Bisphosphonate, such as pamidronate (PAM), have been reported as a sensitizer to trigger tumor cells for Vδ2+ T cells recognition. Valproic acid (VPA) has attracted attentions due to its adjuvant anti-tumor effect with chemotherapy or immunotherapy. Whether PAM and VPA facilitate the immunogenicity of EBV-infected cells towards Vδ2+ T cells cytotoxicity remains unknown. Herein, we demonstrated that lower dosage of VPA and/or PAM did not induce apoptosis of EBV-transformed B lymphoblastoid cell lines (EBV-LCLs) or Vδ2+ T cells. Notably, pre-treatment with PAM significantly increased the cell death of EBV-LCLs after co-culture with Vδ2+ T cells at different ratios. Combining treatment with VPA reinforced the sensitizing effect of PAM. This efficacy was through inducing the accumulation of mevalonate pathway intermediates and dependent on the γδ T cell receptor of Vδ2+ T cells. Similar sensitizing effects of PAM and PAM plus VPA were also demonstrated on the primary PTLD cells. These results highlight the roles of PAM and VPA in the enhancement of immune surveillance and expand the fields of these two drugs in the treatment of different types of malignancies.

As two typical silicon source carrier, the features of diatomite and Santa Barbara Amorphous-15 (SBA-15) supported Mn-based sorbents for moderate-temperature flue gas desulfurization are investigated in this paper. The framework structure, high mechanical strength and large density of diatomite make great contributions to the high desulfurization efficiency (96%) of diatomite supported Mn-based sorbents (MxDy). Nevertheless, the excessive Mn doping (50 wt%) exhibits the decline in desulfurization efficiency, resulting from the self-seeding nucleation and the bareness of micro-pores. Compared to M4D6, the dispersion of active component on the surface of SBA-15 is much more uniform and the sulfur capacity of SBA-15 supported Mn-based sorbent (M4S6) is sharply increased from 186 mg/g to 494 mg/g. On the other hand, the small density of SBA-15 and formation of some bare micro-regions of Mn2O3 in M4S6 lead to the weak contact between SO2 molecule and the active component on the surface of sorbent, as well as the decrease of desulfurization efficiency of M4S6 (88%). Further, the desulfurization mechanism of M4D6 and M4S6 is explored through analyzing the chemical reaction, external mass transfer and internal diffusion. The modular Mn/diatomite-SBA sorbents are developed by combining the advantages of M4D6 and M4S6. When the weight ratio of M4D6 and M4S6 reaches 3:2, the SO2 removal efficiency of modular sorbent and sulfur capacity can reach 96% and 366 mg/g, respectively.

It is a challenge to achieve fast altitude control for hypersonic flight due to the inherently insufficient sensitivity of air density to the near-space altitudes. A dominant open-loop feedforward term and a minor altitude error correction term are combined together to obtain the elevation angle command in this paper. A cascade control strategy is used to calculate the elevation command while ensuring the attitude stability. Moreover, an extended state observer is employed to achieve precise and robust attitude control simultaneously, and a stability margin tester is used to tune the controller explicitly. Extensive simulations are conducted to validate the effectiveness, robustness and measurement noise sensitivity of the proposed method.

Experimental and numerical analyses were performed to predict the deformation parameters of functional powder/solid composite clad rods. There has been a lack of theoretical equations for quantitative analyses of parameters during the deformation of structural powder/solid composite clad rods such as a core filled tube (COFT). In this study, a slab method was adopted to analyze the COFT drawing process, and static equilibrium equations were developed and solved to determine the drawing force, wall thickness and core density. The prediction results of the new equations were compared with experimental results, revealing good agreement between them. Both the equations and the experiments showed the existence of an ultimate relative density of the core material during the COFT drawing process. The influences of the process parameters on the compaction factor and ultimate relative density of the core material were determined using the new equations.

Ta–Si–N/Ag nanocomposite thin films were prepared by reactive magnetron co-sputtering of Ta, Si and Ag targets in the plasma of N 2 and Ar. It was found that Ag nano-grains were uniformly distributed in the amorphous matrix due to the incorporation of Si. The sizes of Ag grains and the separation between them could be well controlled by changing the Si component, which can be adopted to improve the electronic properties of the composite resistive films. A near-zero temperature coefficient of resistance (TCR) of +39.7 ppm/K was obtained in the thin films with a Si component of 5.88 at.% as a result of the balance of quantum tunneling effect and phonon scattering effect. This is consolidated by the changes in the measured carrier density and Hall mobility at different temperatures. Particularly, the near-zero TCR could be maintained at an extremely low temperature from 105 K to 225 K. The results are of great significance for the exploitation of high-performance resistive thin films.

Al + Fe2O3 + BaO2 and NaNO3 as the reactive system and the foaming agent, respectively, are used to prepare barium ferrite hollow microspheres (BFHMs) by self-reactive quenching technology based on flame spraying technology, self-propagating high-temperature synthesis (SHS) technology and quick chilling technology. Effects of NaNO3 on the particle size, morphology, phase structure and microwave absorption properties of BFHMs are investigated through SEM, XRD, particle size analyzer, high-speed camera and vector network analyzer. The results show that, after adding 10 wt.% NaNO3, the average particle size of BFHMs decreases initially from 28 μm to 6 μm, as well as the particle distribution gets narrower. Micro-nano lamellar crystals appear on the surface of BFHMs, with the dimension ranging from 500 nm to 2 μm. BaFe2O4 and Fe3O4, which have spinel structures, can be seen in XRD, and they are beneficial for microwave absorption properties. The real part (ɛ′), imaginary part (ɛ″) of permittivity, and the imaginary part of permeability (μ″) increases in 0.5–18 GHz. The real part (μ′) of permeability increases in 0.5–10.3 GHz, while decreases in 10.3–18 GHz. The microwave absorption properties are improved greatly, and the minimum reflectivity decreases from −3.1 dB to −9.8 dB. The reasons for improvement of microwave absorption properties after adding NaNO3 foaming agent may be the decreasing of the particle size of BFHMs, the appearance of ferrites (BaFe2O4 and Fe3O4) with spinel structure and special micro-nano tabular crystals. Magnetoplumbite-type barium ferrites (BaFe12O19) hollow microspheres are obtained after heat-treatment and the microwave absorption properties are further improved.

Micro-arc oxidation films are fabricated on the surface of AZ31B magnesium alloy in the Na 2 SiO 3 electrolyte. The mechanical performance of magnesium alloy bonding with the adhesive is examined by single lap-shear test, and the morphology and composition of the oxidation film are characterized by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). The data indicate that the increase of Na 2 SiO 3 solution concentration results in the decrease of bonding strength of magnesium alloy joints, while the porosity has no directly relation with the variation of the lap-shear strength. The results also show that Na 2 SiO 3 participates into the film formation and the fabricated film is mainly composed of MgO and Mg 2 SiO 4 . In particular, with the increase of Na 2 SiO 3 solution concentration, the content of MgO decreased while that of Mg 2 SiO 4 increased. Moreover, MgO could initiate the formation of the hydroxyl group, which potentially enhances surface wettability and hydrogen bonding with the adhesive. This rationale is strongly supported by the results of Fourier Transform infrared spectra (FTIR), X-ray photoelectron spectroscopy (XPS) and contact angle measuring.

Objective: The purpose of this 13-study (seven double-blind/placebo-controlled, six open-label) meta-analysis is to determine the effectiveness and tolerability of long-term atomoxetine treatment among young children with attention-deficit/hyperactivity disorder (ADHD). Method: Data were pooled from 6- and 7-year-olds ( N = 272) who met DSM-IV criteria for ADHD, received atomoxetine treatment, and were enrolled in clinical trials of ≥2 years. Of these, 97 subjects reached the 24-month time point, providing data for long-term trend analysis of safety and effectiveness. Results: Effectiveness for most subjects was maintained over long-term treatment, as demonstrated by total scores and total T scores on the Attention-Deficit/Hyperactivity Disorder Rating Scale-IV-Parent Version, investigator administered and scored. During the 2-year period, 25.7% discontinued because of lack of effectiveness, but adverse events were clinically minor and transient, and only 4.0% of children discontinued because of an adverse event. Notable effects on growth were seen during early phases of the study, with attenuation occurring by the 2-year time point. Statistically significant increases in pulse and blood pressure and decreases in cardiac PR interval were seen, but no changes were deemed both statistically significant and clinically meaningful among any vital signs, electrocardiographic measures, or laboratory tests. Conclusion: Long-term atomoxetine treatment appears generally well tolerated and effective in the treatment of young children with ADHD.