[Degradation of Ciprofloxacin by CuNiFe LDHs/BiO2-x Heterojunction-activated Peroxymonosulfate Under Visible Light Irradiation].

Herein, a CuNiFe LDHs/BiO2-x composite photocatalyst was successfully synthesized using a hydrothermal method and applied to activate peroxymonosulfate to degrade ciprofloxacin under visible light irradiation. Owing to the synergistic effect of photocatalysis and PMS activation, a high removal efficiency of CIP up to 88.3% was achieved. The prepared photocatalysts were characterized using XRD, FT-IR, SEM, XPS, UV-Vis DRS, and other methods. The optimal loading amount of CuNiFe LDHs was determined, and the effects of PMS dosage, initial pH value, and inorganic anions (Cl-, CO32-, and NO3-) on the degradation were investigated. Electron paramagnetic resonance and free radical trapping experiments demonstrated that·OH and h+ were the main active species for degrading CIP, and the possible degradation mechanism of the system was proposed.

Structure, phase evolution, and microwave dielectric properties of (Ag0.5Bi0.5)(Mo0.5W0.5)O4 ceramic with ultralow sintering temperature.

In the present work, the microwave dielectric ceramic (Ag0.5Bi0.5)(Mo0.5W0.5)O4 was prepared by using the solid-state reaction method. (Ag0.5Bi0.5)(Mo0.5W0.5)O4 was found to crystallize in the scheelite structure, in which Ag(+) and Bi(3+) occupy the A site randomly with 8-coordination while Mo(6+) and W(6+) occupy the B site with 4-coordination, at a sintering temperature above 500 °C, with lattice parameters a = b = 5.29469(2) Å and c = 11.62114(0) Å, space group I4(1)/a (No. 88), and acceptable Rp = 9.38, Rwp = 11.2, and Rexp = 5.86. High-performance microwave dielectric properties, with permittivity ∼26.3, Qf value ∼10,000 GHz, and temperature coefficient ∼+20 ppm/°C, were obtained in the sample sintered at 580 °C. Its chemical compatibility with aluminum at its sintering temperature was revealed and confirmed by both X-ray and energy dispersive spectrometer analysis. This ceramic could be a good candidate for ultralow-temperature cofired ceramics.

Influence of Ce substitution for Bi in BiVO4 and the impact on the phase evolution and microwave dielectric properties.

In the present work, the (Bi1-xCex)VO4 (x ≤ 0.6) ceramics were prepared via a solid-state reaction method and all the ceramic samples could be densified below 900 °C. From the X-ray diffraction analysis, it is found that a monoclinic scheelite solid solution can be formed in the range x ≤ 0.10. In the range 0.20 ≤ x ≤ 0.60, a composite region with both monoclinic scheelite and tetragonal zircon solid solutions was formed and the content of the zircon phase increased with the calcined or sintering temperature. The refined lattice parameters of (Bi0.9Ce0.1)VO4 are a = 5.1801(0) Å, b = 5.0992(1) Å, c = 11.6997(8) Å, and γ = 90.346(0)° with the space group I112/b(15). The VO4 tetrahedron contracts with the substitution of Ce for Bi at the A site, and this helps to keep the specific tetrahedron chain stable in the monoclinic structure. The microwave dielectric permittivity was found to decrease linearly from 68 to about 26.6; meanwhile, the quality factor (Qf) value increased from 8000 GHz to around 23900 GHz as the x value increased from 0 to 0.60. The best microwave dielectric properties were obtained in a (Bi0.75Ce0.25)VO4 ceramic with a permittivity of ∼47.9, a Qf value of ∼18000 GHz, and a near-zero temperature coefficient of ∼+15 ppm/°C at a resonant frequency of around 7.6 GHz at room temperature. Infrared spectral analysis supported that the dielectric contribution for this system at microwave region could be attributed to the absorptions of structural phonon oscillations. This work presents a novel method to modify the temperature coefficient of BiVO4-type materials. This system of microwave dielectric ceramic might be an interesting candidate for microwave dielectric resonator and low-temperature cofired ceramic technology applications.

Diaqua-bis(5-carb-oxy-1H-pyrazole-3-carboxyl-ato-κN,O)cobalt(II) dihydrate.

In the title complex, [Co(C(5)H(3)N(2)O(4))(2)(H(2)O)(2)]·2H(2)O, the Co(II) ion lies on an inversion center and is coordinated in a distorted octa-hedral environment. In the crystal structure, complex and water mol-ecules are linked into a three-dimensional network by O-H⋯O and N-H⋯O hydrogen bonds.

Diaqua-bis(pyrazine-2-carboxyl-ato-κN,O)manganese(II) dihydrate.

In the title compound, [Mn(C(5)H(3)N(2)O(2))(2)(H(2)O)(2)]·2H(2)O, the Mn(II) atom, lying on an inversion centre, has a distorted octa-hedral environment and the molecules are linked by O-H⋯O and N-H⋯O hydrogen bonds to form a three-dimensional supra-molecular structure.