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A novel series of tetraaza macrocyclic complexes of biological importance was synthesized by “in situ” template reaction between triethylenetetramine and dibenzoylmethane in the presence of trivalent Fe and Cr metal salts in 1:1:1 molar ratio. These complexes are represented by molecular formula [M(C${}_{21}$H${}_{26}$N${}_4)$X]X₂; $M=\mathrm{\text{Fe}}$(III) and Cr(III); $X={\mathrm{\text{Cl}}}^{-}$, NO${}_3^{-}$, −OAc; C${}_{21}$H${}_{26}$N${}_4=\mathrm{\text{macrocyclic}}$ ligand. The reported complexes were characterized by using various physicochemical and spectroscopic techniques including elemental analyses, molar conductance, thermo-gravimetric analysis, FTIR, UV–Visible and mass spectral studies. The results obtained from analytical techniques and spectroscopic techniques together suggested the complexes have a square pyramidal geometry. Various computational studies were performed including molecular docking and modeling. Further, macrocyclic complexes were also screened for their “in vitro” antimicrobial activity against selected bacterial and fungal strains. The antioxidant activity of these complexes was also evaluated. Some of the complexes were found to possess remarkable antimicrobial activity and antioxidant activity. However, complex [Fe(C${}_{21}$H${}_{26}$N${}_4)$(NO${}_3)$](NO${}_3{)}_2$ was found to be most potent against selected bacterial and fungal strains. On the other hand, complex [Cr(C${}_{21}$H${}_{26}$N${}_4)$(NO${}_3)$](NO${}_3{)}_2$ was found to show best antioxidant activity with lowest value of IC${}_{50}$.

The Circular Electron Positron Collider (CEPC) was proposed by the Chinese particle physics scientists as a future Higgs factory and $W/Z$ factory. It will produced more than $10^{12}$$Z$ bosons by operating at a center-of-mass energy around 91.2 GeV in two years. In this study, the measurement of the relative decay widths of $Z$ bosons decaying to $b$ quarks $(R_b)$, $c$ quarks $(R_c)$ and light quarks $(R_{uds})$ in hadronic $Z$ decays are studied on CEPC Monte Carlo (MC) samples. By using a template method, $R_b$, $R_c$ and $R_{uds}$ can be fitted from reconstructed data as the fractions of MC templates with different flavors. The distribution of a sensitive variable, $b$-tagging probability, is used as the template, because of its high performance in discriminating different flavors. Based on the expected statistics of $10^{12}$$Z$ bosons at CEPC, the statistical uncertainty is estimated to be approximately $10^{-6}$ by using the template method, which means that the measurement will no longer be limited by the statistics. Systematic errors arise directly from the difference in the $b$-tagging probability distribution between real data and template MC samples. By considering the bias of input variables used for $b$-tagging probability computing, the quantitative effect for each kind of input variable is investigated by using an ensemble test procedure.

Photocatalytic technology is currently the most promising technology for environmental pollution control. The preparation of photocatalysts with excellent properties is the core of the development of photocatalytic technology. TiO₂ can form a heterojunction with g-C₃N₄, which can effectively inhibit the recombination of photogenerated electron–hole pairs, improve the mobility of photogenerated carriers, and thus improve the photocatalytic performance. In this study, NaCl was used as a template, and the loose and porous g-C₃N₄/TiO₂ heterojunction composite photocatalysts were prepared by the template method. Compared to the pure g-C₃N₄ prepared by the conventional thermal polycondensation method and TiO₂, the g-C₃N₄/TiO₂ heterojunction composite photocatalysts prepared in this study exhibited a greatly increased specific surface area, an improved light absorption performance, a significantly suppressed recombination of photogenerated electrons and holes. Furthermore, the g-C₃N₄/TiO₂ heterojunction composite photocatalysts exhibited excellent photocatalytic performance.

Visible luminescent hybrid titania macroporous materials doped with Eu(DBM)₃⋅H₂O complex (Eu(DBM)₃⋅H₂O/TiO₂-M, M = macroporous, DBM = dibenzoylmethanate) were synthesized with poly(methyl methacrylate) nanospheres (PMMAs) as templates. The obtained Eu(DBM)₃⋅H₂O/TiO₂-M exhibit close-packed spherical porous structure and characteristic red emission of the Eu³⁺ ion. Moreover, diffuse reflectance (DR) and photoluminescence (PL) spectra suggest that the Eu(DBM)₃⋅H₂O complex were successfully doped into the macroporous titania matrix. The FT-IR, luminescent lifetimes, N₂ adsorption-desorption isotherm, and emission quantum efficiency were further investigated.

A series of porous metal oxides nanowires (Fe₂O₃, Co₃O₄, NiO and CuO) have been successfully synthesized, where commercial carbon nanofibers were used as the template. The obtained samples were systematically characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), UV–Vis diffuse reflectance (UV–Vis DR) spectra and transmission electron microscope (TEM). According to the photodegradation data, the porous metal oxides nanowires exhibit significantly photocatalytic activity for degrading tetracycline (TC). Furthermore, the porous Fe₂O₃ nanowires show the best photocatalytic performance among all the samples.

Hydrogen generation from the catalytic hydrolysis of sodium borohydride has many advantages, and therefore, significant research has been undertaken on the development of highly efficient catalysts for this purpose. In our present work, Co₃O₄ nanowires were successfully synthesized as catalyst precursor by employing SBA-15 as a hard template. For material characterization, high-resolution transmission electron microscopy (HRTEM), powder X-ray diffraction (XRD), fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and N₂ adsorption isotherms were employed, respectively. To measure the catalyst activity, typical water-displacement method was carried out. Using a reaction solution comprising 10wt.% NaBH₄ and 2wt.% NaOH, the hydrogen generation rate (HGR) was observed to be as high as 7.74L min${}^{-1}$ g${}^{-1}$ at 25${}^{\circ }$C in the presence of Co₃O₄ nanowires, which is significantly higher than that of CoB nanoparticles and commercial Co₃O₄ powder. Apparent activation energy was calculated to be 50.9kJ mol${}^{-1}$. After recycling the Co₃O₄ nanowires six times, HGR was decreased to be 72.6% of the initial level.