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A new energetic metal-organic framework, [Ag2 (HOBTT)]n, was prepared by solvothermal method using 4, 5-bis (1-hydroxy-tetrazol)-1,2,3-triazole (H3OBTT) as ligand and Ag( I ) as metal center. The structure was characterized by single crystal X-ray diffraction (SXRD), powder X-ray diffraction (PXRD), infrared spectroscopy (IR) and elemental analysis (EA) . The thermal stability was studied by differential scanning calorimeter (DSC) and thermogravimetric (TG) analyzer. The non-isothermal kinetic parameters of thermal decomposition were calculated by Kissinger's method. The mechanical sensitivities of [Ag2 (HOBTT)]n were investigated by impact sensitivity meter and friction sensitivity meter. The GGA-PBE functional was used to calculate the detonation heat, and the detonation velocity and detonation pressure were obtained by Kamlet-Jacobs equation. The results show that [Ag2 (HOBTT)]n is a three-dimensional solvent-free framework, belonging to the orthorhombic crystal system and Fddd space group with crystal density of 3. 309 g/cm3 . The initial thermal decomposition temperature of [Ag2 (HOBTT)]n is 586. 6K, corresponding thermal decomposition kinetic parameters Ea = 255. 18kJ/mol and ln(/\/s-1 ) = 43. 30. Its impact sensitivity is greater than 40J, friction sensitivity is 108N, detonation velocity and detonation pressure are 9.73km/s and 56.38GPa, respectively, showing that [Ag2 (HOBTT)]n is a kind of promising energetic material with good thermal stability,moderate mechanical sensitivity,and excellent detonation performance. [ABSTRACT FROM AUTHOR]

Tn this study, Tn-doped MoO3 nanobelts were synthesized using a hydrothermal method to investigate the effects of Tn doping concentration on their physical phase, morphology, and room-temperature hydrogen sensing properties. The results revealed that the Tn-doped products were orthorhombic MoOs nanobelts with an average length of approximately 5/im and a diameter of about 200 nm. As the Tn-doping concentration increased from 2 to 6 at %, the room-temperature hyd rogen sensing properties of the nanobelts were gradually enhanced. However, the properties deteriorated when the Tn-doping concentration was further increased to 1 Oat%. The MoO3 nanobelts with a doping concentration of 6at % exhibited the best room-temperature hydrogen sensing performance, with a response of approximately 1.84 to 3000 ppm H2 and a response time of about 42 s. Moreover, the Tn-doped MoO3 nanobelts showed good repeatability to hydrogen and exhibited excellent selectivity and stability. [ABSTRACT FROM AUTHOR]

Photodynamic antimicrobial therapy (PDAT) is a new method for the treatment of microbial infections. However, there have been few reports on the photodynamic antimicrobial activity of corrole, which has a significant advantage in the treatment of photodynamic antitumor activity. In this study, mono-hydroxyl corrole named 10-(4-hydroxyphenyl)-5,15-bis (pentafluorophenyl) corrole (P-OH) was synthesized. What' s more, its crystal structure and photodynamic antibacterial activity were also explored. The results indicate that mono-hydroxyl corrole belongs to orthorhombic crystal system and shows good photodynamic antibacterial activity. When the concentration of the drug is more than 2MIC, the bacteriostatic effect is showed. Whereas, the concentration of drug less than 2MIC shows antibacterial effect. The minimum bactericidal concentration and minimum inhibitory concentration of the drug are lower than porphyrin, it is a good photodynamic antibacterial photosensitizer. [ABSTRACT FROM AUTHOR]

All-inorganic metal halides have shown significant applications in solid-state optoelectronics because of their flexible structures and impressive fluorescence emissions. In this study, a heterovalent cation substitution strategy was used to partially replace the divalent cadmium ions in CsCdCl3 with trivalent antimony ions to promote the production of self-trapped excitons, resulting in a bright broadband green photoluminescence of CsCdCl3∶ Sb3+ with a central wavelength of 530 nm. Mechanism researches results show that the adjacent SbCl6 octahedra in CsCdCl3∶ Sb3+ are isolated, forming a low-dimensional electronic configuration that promotes Sb3+ localization and achieves efficient photoluminescence with a quantum efficiency of up to 95. 5% . Furthermore, although both CsCdCl3 and RbCdCl3 belong to ACdCl3 ( A is an alkali metal family), they have distinctly different crystal structures. RbCdCl3 crystallizes in the orthorhombic crystal system with space group of Pnma; while CsCdCl3 crystallizes in the hexagonal phase crystal system with space group of P63/ mmc. The structural symmetry of CsCdCl3 is higher than that of RbCdCl3, indicating that its crystal structure is less distorted away from the cubic phase than that of RbCdCl3, resulting in a smaller Stokes shift and corresponding blue shift of the emission spectrum in CsCdCl3∶ Sb3+ than in RbCdCl3∶ Sb3+. This work not only provides a method for designing new photoluminescence materials by heterovalent cation substitution but also paves an avenue for modulating the luminescent properties of metal halides through crystal structure symmetry. [ABSTRACT FROM AUTHOR]

Py-FeO2, Py-FeOOH and ε-FeOOH are important components of mantle and core-mantle boundary. Their physical evolution characteristics at high temperature and high pressure are important for understanding the composition, structure and dynamic process of mantle. The crystal structures and elastic properties of Py-FeO2 and Py-FeOOH at 0-350 GPa and ε-FeOOH at 0-170 GPa were calculated by first principles in this study. The Py-FeO2 and Py-FeOOH belong to the cubic crystal system, their lattice constants decrease gradually with increasing pressure. The ε-FeOOH belongs to orthorhombic crystal system, and its lattice constants decrease with increasing pressure, however, a and b axes bump up at 33 GPa, while c axis swoop at 33 GPa. The cell densities of Py-FeO2, Py-FeOOH and ε-FeOOH increase with pressure, and the relative cell density among these three phases is Py-FeO2 > Py-FeOOH > ε-FeOOH. The bulk moduli of Py-FeO2, Py-FeOOH and ε-FeOOH increase linearly with pressure, and the shear moduli of Py-FeO2 and Py-FeOOH increase linearly with pressure, but the shear modulus of ε-FeOOH mutates at 33 GPa. Py-FeO2 has the highest bulk modulus, and Py-FeOOH and ε-FeOOH have almost the same bulk modulus at high pressures. In addition, Py-FeO2 has the largest shear modulus, and ε-FeOOH has the smallest shear modulus. The compression wave velocities of Py-FeO2, Py-FeOOH and ε-FeOOH decrease gradually with the increasing pressure, while the shear wave velocities of Py-FeO2 increase gradually with the increasing pressure. The shear wave velocity of Py-FeOOH decreases with the increasing depth in the range of 0-2 000 km, and the variation is small in the range of 2 000-6 000 km (5.8 km/s < vs < 6.0 km/s). The shear wave velocities of ε-FeOOH mutate at 33 GPa (about 900 km depth). The wave velocity of ε-FeOOH is the lowest, while that of Py-FeO2 is the highest. Based on comprehensive theoretical calculations, it is found that Py-FeO2 and Py-FeOOH have the high density and low wave velocity characteristics, which are consistent with the properties of the mantle ultra-low velocity zone (ULVZs). Py-FeO2 and Py-FeOOH may enrich and sink to the core-mantle boundary after formation, becoming the source of the ULVZs. The hydrogen bond symmetry of ε-FeOOH under 33 GPa may affect the crystal structure of ε-FeOOH, the atomic interactions of ε-FeOOH, and then the elastic properties and seismic wave velocity of ε-FeOOH. [ABSTRACT FROM AUTHOR]