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Abstract: A new type of flower-like ZnO nanostructure was prepared on a large scale through a very simple solvothermal method. The nanoflowers are assembled by many thin and uniform hexagonal-structured ZnO nanosheets, with a thickness of around 6nm. The growth mechanism of the nanoflowers is discussed based on the reaction conditions. Room-temperature optical measurements reveal that such ZnO nanoflowers have very strong UV bandedge emission with a large Stokes shift and an asymmetrical band profile. This luminescence characteristic may be attributed to the anisotropic energy band structure of the quantum-confined ZnO nanosheets. [Copyright &y& Elsevier]

Due to its similar electrochemistry to that of the lithium (Li)-ion battery but the high abundance of sodium (Na) in the earth, Na-ion battery is expected to be a promising alternative of the former, especially in stationary energy storage applications. Although it has been well-known that the Na-ions can be co-intercalated in graphite in some ether-based electrolytes, a number of important questions related to the Na-ion intercalation remain unclear. In order to better understand the sodium intercalation in graphite, Na-ions were intercalated in highly oriented pyrolytic graphite (HOPG) by immersing the latter in a sodium-biphenyl-monoglyme (Na-BP-DME) solution. The staging behavior that often occurs during Li-ion intercalation in graphite was observed in the Na-intercalated HOPG, on the basis of X-ray diffraction (XRD) and scanning transmission electron microscopy (STEM) characterization. The chemical formula of the DME-Na co-intercalated HOPG was determined to be Na(DME) 2 C 26 by a combination of Fourier-transformed infrared (FTIR) and Raman spectroscopy, thermogravimetry and the above structural characterizing techniques. The negligible impact of co-intercalation on the structural integrity of HOPG demonstrates that HOPG can be a promising anode material of the Na-ion batteries. The lower coordination number between the Na + ions and DME and the interaction between DME and the graphite layers are believed to be responsible for the structural stability of the co-intercalated graphite. Finally the chemical stability of the ternary graphite intercalation compounds in air was evaluated. [ABSTRACT FROM AUTHOR]

• Good epitaxial growth among substrate, Cr 2 O 3 interlayer and crystalline CrO 2 film. • There is a higher oxygen concentration between the Cr 2 O 3 film and substrate. • The Cr 2 O 3 interlayer may be inevitable for generating CrO 2. Epitaxial chromium dioxide (CrO 2) film was grown on sapphire Al 2 O 3 by the chemical vapor deposition (CVD) method. The interfacial structure of the epitaxial CrO 2 was characterized by transmission electron microscopy (TEM), and the spatial distribution of the chromium valence in the film was qualitatively analyzed by electron energy loss spectroscopy (EELS). An uneven transition layer with a diffraction pattern consistent with that of Cr 2 O 3 but with an anomalously large oxygen concentration (Cr/O ≈ 0.2–0.3) was found between the CrO 2 film and the substrate. [ABSTRACT FROM AUTHOR]

In this paper, scanning transmission electron microscopy is used to study the microstructures of the defects in LaCoO 3 /SrRuO 3 multilayer films grown on the SrTiO 3 substrates, and these films have different thickness of SrRuO 3 (SRO) layers. Several types of Ruddlesden-Popper (R.P.) faults at an atomic level are found, and these chemical composition fluctuations in the growth process are induced by strain fields originating from the film-film and film-substrate lattice mismatches. Furthermore, we propose four types of structural models based on the atomic arrangements of the R.P. planar faults, which severely affect the functional properties of the films. [ABSTRACT FROM AUTHOR]

Manganese bromide has attracted enormous attention for its applications in the syntheses of organic-inorganic hybrid compounds. A complete understanding of structural and chemical stabilities of MnBr 2 is important for controlling its properties. Here, we focus on the irradiation resistance of MnBr 2 . The chief purpose of this research is reached by in situ transmission electron microscopy. It is demonstrated that the deliquescent MnBr 2 powder is prone to adsorb the vapor in air, and the hydrous MnBr 2 can be decomposed under its continuous exposure to electron beam, indicated by a transmission electron microscope via the catalysis of Cu grid at room temperature. [ABSTRACT FROM AUTHOR]

A novel electrolyte materials of introducing detonation nanodiamond (DNDs) into samarium doped ceria (SDC) is reported here. 1%wt. DNDs doping SDC (named SDC/ND) can enlarge the electrotyle grain size and change the valence of partial ceria. DNDs provide the widen channel to accelerate the mobility of oxygen ions in electrolyte. Larger grain size means that oxygen ions move easier in electrolyte, it can also reduce the alternating current (AC) impedance spectra of internal grains. The lower valence of partial Ce provides more oxygen vacancies to enhance mobility rate of oxygen ions. Hence all of them enhance the transportation of oxygen ions in SDC/ND electrolyte and the OCV. Ultimately the power density of SOFC can reach 762 mw cm −2 at 800 °C (twice higher than pure SDC, which is 319 mw cm −2 at 800 °C), and it remains high power density in the intermediate temperature (600–800 °C). It is relatively high for the electrolyte supported (300 μm) cells. [ABSTRACT FROM AUTHOR]

Three new modulated structures induced by controllable electron beam irradiation (EBI) were obtained from SrCrO 3 single crystal. The crystal and electronic structures were investigated using aberration-corrected scanning transmission electron microscopy, electron energy loss spectroscopy (EELS) and ab initio calculations. The EELS results revealed that EBI induced ordered oxygen vacancies and generated modulated structures SrCrO 2.5 (I 4 /mmm), SrCrO 2.8 (C 2/ m) and SrCrO 2.67 (C 2 /m) from pristine SrCrO 3 (Pmm). The corresponding structural models were proposed and modified by ab initio calculations. Additionally, the electronic structures of the optimized modulated structures were further investigated. [Display omitted] • SrCrO 3 containing Cr4+ ions possesses anomalous electronic states and physical properties. • By using the aberration-corrected scanning transmission electron microscopy, we found that the electron beam irradiation induces three kinds of modulated structure. • Our work shows the plentiful properties of the material and deepens our understanding on this material. [ABSTRACT FROM AUTHOR]

With the assistance of in situ heating techniques in the transmission electron microscope, the morphology change of the Pt nanowires which were deposited by focus ion beam has been monitored under different temperatures. With a drastic shape expansion, a significant bending has been observed abruptly above 250 °C. The energy dispersive X-ray spectroscopy mapping indicated the asymmetrical distribution of carbon (C), platinum (Pt) and gallium (Ga) within the Pt nanowires while the diffraction analysis revealed the crystalline formation of Ga-Pt alloys during the heating process. The in-situ exploration discovered that besides the recrystallization of Pt nanoparticles, the asymmetrical volume expansion from the Ga-Pt alloys formation should be another factor which induces the shape variation of the heated Pt nanowires. [ABSTRACT FROM AUTHOR]

The commercialization of Sn-based anodes for lithium ion batteries is still hindered due to the inherent volume change leading to a rapid capacity fading during the electrochemical cycle. Inspired by echeveria , a plant that stores sufficient water in its hierarchical leaves to survive in a drought, we report a breakthrough by designing the hierarchical and nanoporous SnO 2 electrode encapsulated with ultrathin carbon layer (∼2 nm). As evidently captured by in situ transmission electron microscopy, the conformal carbon coating on the surface of anode may provide an elastic cover that suppresses the cracks due to severe volume change, and increases both electrical and ionic conductivity, allowing the cells to exhibit excellent lithium storage performance with more than 800 cycles even with relatively high-rate of current densities. [ABSTRACT FROM AUTHOR]

The orthorhombic (3/2, 2/1) approximant with a = 3.06 nm, b = 1.23 nm, c = 2.24 nm, and the coexisting (2/1, 3/2) approximant of decagonal quasicrystals with a = 1.90 nm, c = 3.64 nm, and β ≅ 90° are found in Al–Cr–Fe–Si alloys by aberration-corrected transmission electron microscope. The structural relationships of these two approximants are analyzed and discussed based on the high-angle annular dark-field scanning transmission electron microscopy images at atomic resolution. We find that both of their structural tiling along the [010] direction can be described by one shield-like tile, with the superiority over the previous HBS tiling model due to the clarity. Combining the shield-like tile and HBS tiling model, the domains of approximants are clearly demonstrated. [ABSTRACT FROM AUTHOR]

Adipose tissue inflammation increases with obesity, but adipocyte vs. immune cell contributions are unclear. In the present study, transcriptome analyses were performed on highly-purified subcutaneous adipocytes from lean and obese women, and differentially expressed genes/pathways were determined in both adipocyte and stromal vascular fraction (SVF) samples. Adipocyte but not SVF expression of NOD-like receptor pathway genes, including NLRP3 and PYCARD , which regulate caspase-1-mediated IL-1β secretion, correlated with adiposity phenotypes and adipocyte class II major histocompatibility complex (MHCII) gene expression, but only MHCII remained after adjusting for age and body mass index. IFNγ stimulated adipocyte MHCII, NLRP3 and caspase-1 expression, while adipocyte MHCII-mediated CD4 + T cell activation, an important factor in adipose inflammation, induced IFNγ-dependent adipocyte IL-1β secretion. These results uncover a dialogue regulated by interactions among T cell IFNγ and adipocyte MHCII and NLRP3 inflammasome activity that appears to initiate and escalate adipose tissue inflammation during obesity. [ABSTRACT FROM AUTHOR]

A transition metal oxide, NbMoO 4 , is synthesized by using a solid-state reaction method, then the morphology of the sample is characterized by the scanning electron microscopy. The X-ray diffraction refinement and transmission electron microscopy results show that the sample has a TiO 2 rutile-type structure with space group P 4 2 / mnm , which is the high-temperature phase of NbO 2 and MoO 2. Our transport result indicates that the resistivity is as low as 0.02 Ω·cm in the temperature range from 2 to 300 K, indicating the metallicity of NbMoO 4. Furthermore, the calculated density of states and experimental specific heat data from 2 to 20 K also confirm the metallic behavior. Our magnetization experiments indicate that the NbMoO 4 exhibits paramagnetism. The valence states of Nb4+ and Mo4+ in NbMoO 4 are revealed by the X-ray absorption spectroscopy. • We have successfully synthesized rutile-structure NbMoO 4 at room temperature, which is the high-temperature structure of NbO 2 and MoO 2. • Magnetic and transport properties of NbMoO 4 are firstly reported. • NbMoO 4 is determined as a paramagnetic metal by experiments and theoretical calculations. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports that the high pressure in situ angle dispersive x-ray diffraction and Raman scattering studies on CoPt and NiPt hollow nanospheres are performed by means of a diamond anvil cell for generating external pressure at room temperature. The crystal structures of both the CoPt and NiP hollow nanospheres keep stable up to about 41GPa. Moreover, it shows that the hollow nanospheres possess higher bulk moduli than their bulk counterparts by using the first-principles density functional theory. [Copyright &y& Elsevier]

Abstract: A simple and effective ball-milling combined calcination method has been developed to prepare MoS2/CdS photocatalysts for visible-light-driven water splitting into H2 for the first time. The photocataysts exhibit very high photocatalytic activities. A H2 evolution rate up to 1315μmolh−1 has been achieved based on 0.9mol% MoS2/CdS (PT) photocatalyst (PT is the abbreviation of pretreatment), which is much higher than 488μmolh−1 for the 0.2wt% Pt/CdS (PT) photocatalyst. In the meantime, this photocatalyst exhibits good anti-photocorrosion property. The ball-milling procedure makes the starting material, (NH4)2MoS4, disperse uniformly on the surface of CdS nanoparticles. Further calcination treatment leads to complete decomposition of (NH4)2MoS4 to afford MoS2/CdS photocatalysts with intimate contacts between the two components. The pretreatment of CdS also has important positive effect on photocatalytic activity. Similar reactions by attempting different kinds of commercial CdS products have been carried out, indicating this preparation method is universal. [Copyright &y& Elsevier]

Abstract: Aim of the study: The purpose of this study was to evaluate the efficacy and safety of a topical Chinese herbal medicine (CHM) compound Tangzu Yuyang Ointment (TYO) for treatment of chronic diabetic foot ulcers. Materials and methods: This multi-center, prospective, randomized, controlled and add-on clinical trial was conducted at seven centers in the China mainland. Fifty-seven patients with chronic diabetic foot ulcers of Wagner''s ulcer grade 1–3 were enrolled in this study. Patients who were randomly assigned to the control group (n =28) received standard wound therapy (SWT), whereas those randomized to the treatment group (n =28) received SWT plus topical TYO. Only 48 patients who finished 24 weeks of observations were entered for data analysis. Results: The TYO and SWT groups were comparable for baseline characteristics. Ulcer improvement was 79.2% in the TYO group and 41.7% in the SWT group (P =0.017) at 12 weeks, and 91.7% vs. 62.5% (P =0.036) at 24 weeks. The number of ulcers that were completely healed at 4, 12 and 24 weeks was similar in both groups, as were the numbers of adverse events. Healing time was 96±56 days (n =19) in the TYO group and 75±53 days (n =14) in the SWT group (P =0.271). Conclusion: TYO plus SWT is more effective than SWT in the management of chronic diabetic foot ulcers and has few side-effects. [Copyright &y& Elsevier]

Abstract: Nanosintering behaviour of MgAl2O4 ultra-fine powder was investigated under high pressure. We found that the nanosintering mechanism under high pressure was quite different from that under ambient pressure. To shed light on the mechanism, the residual stress, grain size, and boundary situation were investigated using HRTEM and XRD, respectively. Our results show high pressure can restrain grain growth and initiate plastic deformation to eliminate pores and/or additional phases existing in triple junctions of the grains. However, the conventional sintering process is controlled by grain growth to avoid imperfections between grain boundaries when preparing transparent ceramics. [Copyright &y& Elsevier]

Abstract: Activated carbon was treated at 5GPa up to 1600°C, and the structural evolution in the graphitization process was investigated. The graphitization temperature is equal to 1200°C at 5GPa, reflected by X-ray diffraction (XRD) patterns. Honeycomb-like structures in micron scale come into being in the high-pressure sintering temperature range of 1000−1100°C and slice-like structures appear after graphitization. The existence of D and D’ lines in the Raman spectra for the graphitized-activated carbon indicates that there are still some disordered structures. The continuous occurrence of variable-range hopping, the approximately linear ρ–T relationship, and semimetal conduction mechanism accords with the graphitization process. [Copyright &y& Elsevier]

• SCO-LSMO bilayer films are fabricated by PLD technique. • SCO has been defined to be Ima 2 structure. • Domains and stack-fault structures are detected in SCO layer. • A peculiar nanocrystalline embeds in the SCO-LSMO interface. SrCoO 3-δ (0 < δ < 0.5) film has shown great potential in applications for interface engineering of spintronic devices due to its multiformity of crystal structures and magnetic properties. In this work, we have studied the microstructures of SrCoO 3-δ in SrCoO 2.5 -La 0.67 Sr 0.33 MnO 3 (SCO-LSMO) double-layered films by using scanning transmission electron microscopy. Our fabricated SCO film is determined to have a structure with the Ima 2 space group (No. 46). Perpendicular domain and stack-fault structures are observed to coexist in the SCO layer. In the joint of domains, oxygen content remains a constant for octahedra layers but a slight rise for tetrahedra layers. Continuous changes of oxygen content are also detected in the same level layer in the stack-fault region near the domain boundary. Besides, a peculiar nanocrystalline is observed at the interface of SCO-LSMO. The electron energy-loss spectroscopy results show that the Co ions in nanocrystalline have a lower valence, indicating a chemical compositon of SrCoO 2.5-δ (0 < δ < 0.5). [ABSTRACT FROM AUTHOR]

Compared with 3 d -electron transition metal oxides (TMOs), 5 d -electron TMOs, particularly iridates, have strong competition between spin-orbit coupling and on-site Coulomb repulsion due to their comparable energies. By using aberration-corrected transmission electron microscopy, we have studied at an atomic scale the Sr 3 Ir 2 O 7 sample with a bilayered perovskite structure, which is synthesized under high pressure and high temperature. In addition, we have also investigated its magnetic and electrical properties. Our results show that the Sr 3 Ir 2 O 7 possesses two kinds of structures: a tetragonal structure (I 4 /mmm) and an orthorhombic structure (Ccce) with complex magnetic and electrical properties. We observed that there are often 90° domain structures along the b axis of the orthorhombic structure of Sr 3 Ir 2 O 7 , which might be associated with the essence of antiferromagnetic 90° domains. • Two structures, I 4/ mmm and Ccce , are found to coexist in high pressure synthesized Sr 3 Ir 2 O 7. • Sr 3 Ir 2 O 7 shows anomalous magnetic and electrical properties. • Domain structure in orthorhombic Sr 3 Ir 2 O 7 may induce the 90° antiferromagnetic domains. [ABSTRACT FROM AUTHOR]

In conventional crystals, the 180° domain is generally reflected by the inversed arrangement of the orientation of unit cells in nearby domains. Herein, we report a special 180° domain related to the inverse arrangement of structural blocks in structurally complex phases in an Al 60 Cr 20 Fe 10 Si 10 alloy. The structural features were investigated in detail by high-angle annular dark-field scanning transmission electron microscopy with atomic resolution. Furthermore, the corresponding projected structural models of the domain boundaries were proposed. Finally, the structure and the formation mechanism of the 180° domain are compared and discussed with an antiphase domain in the same alloy system. • We found a novel 180° domain caused by inversed structural blocks. • Atomically resolved structures of the 180° domain are revealed. • Projected structural models of the domain boundaries are proposed. • Formation mechanisms of the 180° domain are discussed. [ABSTRACT FROM AUTHOR]