We demonstrate the application of the combined experimental-computational approach for studying the anionic impurities in hydroxyapatite (HAp). Influence of the carbonation level (x) on the concentration of the NO3(2-) radicals in the HAp nanocrystals of Ca10-xNax(PO4)6-x(CO3)x(OH)2 with x in the range 0 < x < 2 and average sizes of 30 nm is investigated by different analytical methods including electron paramagnetic resonance (EPR). Stable NO3(2-) radicals are formed under X-ray irradiation of nano-HAp samples from NO3(-) ions incorporated in trace amounts during the wet synthesis process. Density functional theory (DFT) based calculations show energetic preference for the PO4 group substitution by NO3(-) ions. Comparison of the calculated and experimental spectroscopic parameters (g and hyperfine tensors) reveals that EPR detects the NO3(2-) radicals located in the positions of the PO4 group only. It is shown that with the increase in x, the carbonate ions substitute the NO3(2-)/NO3(-) ions. DFT calculations confirm that carbonate incorporation in HAp structure is energetically more favorable than the formation of the nitrate defect.
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Plant Signal Behav
December 2024
Department of Microbiology, Faculty of Sciences, Marwadi University Research Center, Marwadi University, Rajkot, India.
BMC Genom Data
February 2024
Anhui Engineering Research Center for Eco-agriculture of Traditional Chinese Medicine, College of Biological and Pharmaceutical Engineering, West Anhui University, 237012, Luan, China.
Objectives: Pb stress has a negative impact on plant growth by interfering with photosynthesis and releasing reactive oxygen species, causing major risks such as heavy metal ion accumulation in the soil matrix. A proteomics experiment was conducted to determine whether protein levels of Dendrobium huoshanense changed in response to Pb stress seven to fifteen days after being sprayed with a 200 mg/L Pb (NO) solution. The proteomic data we gathered provides a model for investigations into the mechanisms underlying Dendrobium plant resistance to heavy metal stress.
View Article and Find Full Text PDFInorg Chem
April 2023
College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao, Shandong 266100, China.
Metal-organic frameworks (MOFs) have exhibited appreciable potential as catalytic agents in the field of material science. The research of new MOFs with dual functions in electrocatalysis and photocatalysis under ultraviolet (UV) irradiation is extremely pivotal for renewable energy applications. Hence, we synthesized a series of three-dimensional MOFs, namely, [Cd(bimb)(HITA)] (-), {[Cd(bimb)](NO)} (-), and [Cd(bimb)(ONO)] (-) (bimb = 1,4-bis(imidazol-1-ylmethyl)benzene; HITA = 5-hydroxyisophthalic acid), with applicability in the oxygen evolution reaction process and Fenton-like photocatalysis.
View Article and Find Full Text PDFDalton Trans
November 2022
Department of General and Inorganic Chemistry, Faculty of Chemistry, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece.
Two novel halogenated (Br- and F-) quinazoline derivatives, namely [()-4-(2-((6-bromopyridin-2-yl)methylene)hydrazinyl)quinazoline] (L1) and [()-4-(2-((3-fluoropyridin-2-yl)methylene)hydrazinyl) quinazoline] (L2), were synthesized and characterized. Their interaction with a series of metal(II) ions (= Mn(II), Ni(II), Cu(II), Zn(II) and Cd(II)) resulted in the formation of six mononuclear complexes characterized by spectroscopic techniques and single-crystal X-ray crystallography. The complexes bear the formulae [Ni(L)](NO) (1), [Zn(L)](NO)(PF) (2), [Cd(L)(HO)(CHOH)(NO)](NO) (3), [Cu(L)Cl] (4), [Ni(L)](NO) (5) and [Mn(L)(CHOH)(Cl)] (6).
View Article and Find Full Text PDFChemosphere
July 2022
School of Environmental Engineering, Wuhan Textile University, Wuhan, 430073, PR China; Engineering Research Center Clean Production of Textile Dyeing and Printing, Ministry of Education, Wuhan, 430073, PR China. Electronic address:
To enhance the efficiency of photogenerated electron transport in the photo-Fenton reaction, we report a Fe-doped UiO-66 containing Fe-O-Zr bonds for the photo-Fenton reaction system. The modulation changes the energy bandgap from 3.89 eV to 2.
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