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Based on first-principles calculations using density functional theory, this paper systematically studies the effects of uniaxial tension-compression deformation on the stability and electrical and thermal properties of monolayer graphene and AA stacked bilayer graphene. The study shows that the original symmetry of graphene is broken by the tensile and compression deformations, catalyzing the interlayer coupling of bilayer graphene. Its electronic energy band, phonon dispersion, and other physical properties have changed. The transition from metalloid to semiconductor has completed since the deformation weakens the stability of the graphene system to varying degrees and opens the band gap of monolayer graphene. The band gap becomes larger with the increase of tensile and compressive deformation, in which way it can be adjusted. Influenced by the tiny tensile deformation, metalloid properties are exhibited by a small band gap of intrinsic AA-stacked bilayer graphene, and then the band gap becomes larger as the deformation increases. A band gap appears in the system phonon dispersion curves when the compression deformation increases to -15%. The phonon mode softens and shows virtual frequency. The value of virtual frequency increases with the increase of compression deformation. At the very moment, the vibration mode is discontinuous, and the system is unstable.

The thermal performance of high-energy hydrazine nitrate complexes [Zn(N2H4)2(NO3)2]n, [Cd(N2H4)2(NO3)2]n, [Co(N2H4)3](NO3)2 and [Ni(N2H4)3](NO3)2 (signed as ZnHN, CdHN, CoHN and NiHN) was researched systematically. The thermal behavior, kinetics, thermal safety and storage life of them were investigated by the DSC, TG and dynamic pressure measuring thermal analysis method. The thermal decomposition of CdHN and ZnHN with NO3 − as ligand is more complicated than CoHN and NiHN with NO3 − as counterion indicating that similar structures have some influence on the thermal properties, but there is no necessary relationship. DSC curves and TG mass-loss stages of CdHN and ZnHN are similar but their thermal decomposition mechanism is quite different.

Uniform α-Fe2O3/amorphous TiO2 core-shell nanocomposites were prepared via a hydrolysis method and α-Fe2O3/anatase TiO2 core-shell nanocomposites were obtained via a post-calcination process. The structure and morphology of the products were characterized by powder X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and scanning electron microscopy. Amorphous TiO2 nanoparticles with diameters of ten to several tens nanometer were formed on the surface of α-Fe2O3 nanoparticles and the coverage density of the secondary TiO2 nanoparticles in the composite can be controlled by varying the concentration of Ti(BuO)4 in the ethanol solution. The visible-light photocatalytic properties of different products towards Rhodamine B(RhB) were investigated. The results show that the α-Fe2O3/amorphous TiO2 exhibits a good photocatalytic property owing to the extension of the light response range to visible light and the efficient separation of photogenerated electrons and holes between α-Fe2O3 and amorphous TiO2.

ZnTa2O6 ceramics with various amount of Al2O3 additive were synthesized by a conventional mixed-oxide route. The grain growth of ZnTa2O6 ceramics was accelerated with Al2O3 additive. However, excessive addition (>1.0 wt%) of Al2O3 leaded to abnormal grain growth. With Al2O3 addition, the Al2O3 additive did not solubilized into ZnTa2O6 structure but resulted in forming the second phase. The Al2O3 addition resulted in the lower sintering temperature of ZnTa2O6 ceramics and improved microwave dielectric properties. The dielectric constant (er) of the samples did not change much and ranged from 32.41 to 34.33 with different amount of Al2O3 addition. The optimized quality factor (Q × f) was higher than 70,000 GHz as a result of the denser ceramics. The temperature coefficient of resonant frequency (τ f ) of the doped ZnTa2O6 ceramics could be optimized to near-zero.

Three one-dimensional metal–nitroxide complexes [Cu(NIT4Py)2(1,4-chdc)] n (1), {[Cu(IM4Py)2(1,4-chdc)(H2O)]·H2O} n (2) and {[Zn(IM4Py)2(1,4-chdc)(H2O)2]·H2O} n (3) (NIT4Py = 2-(4′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, IM4Py = 2-(4′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl and 1,4-chdc = 1,4-cyclohexanedicarboxylate anion) have been synthesized and characterized structurally as well as magnetically. All three complexes crystallize in neutral one-dimensional chains in which the nitroxide–metal–nitroxide units are linked by linear 1,4-cyclohexanedicarboxylate anions. The 1,4-chdc ligands only present the e,e-trans-configuration in these complexes, although there are both cis- and trans-isomers in the free ligand. Magnetic measurements show that complexes 1 and 2 both exhibit weak antiferromagnetic interactions between the copper atoms and nitroxide radicals.

Three new complexes, {[Cu3(2,3-pyma)2(sip)2(H2O)5]·5H2O} n , {[Zn(H-2,3-pyma)(sip)(H2O)]·H2O} n , and {[Cd(H-2,3-pyma)(sip)(H2O)]·H2O} n (2,3-pyma = (2-pyridylmethyl,3-pyridylmethyl)amine and H3sip = 5-sulfoisophthalic acid) were synthesized and structurally characterized by single-crystal X-ray diffraction. The Cu(II) complex crystallizes in neutral two-dimensional layers in which the Cu(II) centers are bridged by both the flexible 2,3-pyma and the rigid sip ligands. The Zn(II) and Cd(II) complexes contain neutral one-dimensional chains linked by the rigid sip anions, whereas the flexible H-2,3-pyma ions only act as terminal ligands. The Cu(II) complex shows weak antiferromagnetic interactions, while the Zn(II) and Cd(II) complexes exhibit fluorescent emissions in the solid state.

Three new complexes, {[Mn(Hbpma)2(pm)(H2O)2]·8H2O}n, {[Co(Hbpma)2(pm)(H2O)2]·8H2O}n and {[Zn(Hbpma)2(pm)(H2O)2]·8H2O}n (bpma = N,N′-bis(3-pyridylmethyl)amine and H4pm = pyromellitic acid) were synthesized and structurally characterized by single-crystal X-ray diffraction. All three complexes are isomorphous consisting of one-dimensional coordination polymers bridged by rigid pm ligands, while the flexible dipyridyl bpma only acts as a terminal ligand. The bpma ligand adopts the trans–trans conformation in all three complexes. The magnetic properties of the Mn(II) and Co(II) complexes show the occurrence of antiferromagnetic interactions between adjacent metal atoms. The Zn(II) complex exhibits fluorescent emission in the solid state at room temperature.

In this paper COX’s superpotential is extended to double complex form firstly, then how to get hyperbolic complex superpotential from the known ordinary complex superpotential is discussed, finally, new solutions of stationary axisymmetric gravitational fields are shown with a few specific cases.

Experimental results of an azo dye (reactive brilliant red X-3B, RBR X-3B) decolorization and degradation in a white rot fungal biofilm reactor were introduced and discussed. The fungal biofilm reactor is highly potential for dye decolorization and degradation with the highest decoloring rate of 95% within 96 hours reaction time at initial pH 4. 5 under high nitrogen level (HN) (24 mmol/L ammonium tartrate) condition. Experimental conditions, such as nutrient nitrogen levels in reaction mixture and initial pH, significantly affected dye decolorization and degradation. Effluents from this biofilm reactor can be well treated to meet the discharging requirements by use of chemical flocculation. RBR X-3B was first absorbed onto fungal biomass and then degraded gradually. The SH-13 fungus monopolized the biofilm throughout the experiments, though the reactor was exposed to open air for 4 months.