FT-IR, XPS, and DFT Study of Adsorption Mechanism of Sodium Acetohydroxamate onto Goethite or Hematite

The adsorption of sodium acetohydroxamate on the goethite or hematite surface was investi- gated by Fourier transform infrared spectroscopy （FT-IR）, X-ray photoemission spectroscopy and periodic plane-wave density functional theory （DFT） calculations. The core-level shifts and charge transfers of the adsorbed surface iron sites calculated by DFT with periodic in- terfacial structures were confronted to the X-ray photoemission experiments. FT-IR results reveal that the interracial structure of sodium acetohydroxamate adsorbed on the goethite or hematite surface may be assigned to a five-membered ring complex. In agreement with the adsorption energies determined by the DFT calculations, a five-membered ring complex is formed via bonding of one surface iron atom of goethite （101） or （100） to both oxygen atoms of hydroxamate group, and these two oxygen atoms of the hydroxamate group correspond- ingly attach to two neighboring iron atoms of the goethite surface. But a five-membered ring complex between two oxygen atoms of the hydroxamate group and one surface iron atom of hematite （001） is formed without any extra attachments. The calculated core-level shifts of Fe2p for the interracial structures are correspondingly in good agreement with the experimental observed one, which confirmed the reliability of the calculated results.

γ-Ray radiolysis of acetohydroxamic acid in HNO_3 and its radiolytic product

Acetohydroxamic acid(AHA) is a novel saltfree reagent used for the separation of Pu and Np from U in the advanced Purex process. This paper reports the c-ray damage of AHA in HNO_3 and its radiolytic product. For 0.2 mol L^(-1) AHA in 0.2–2.0 mol L^(-1) HNO_3 irradiated at a dose of 5–25 kGy, the radiolytic rate of AHA is6.63–77.5%, and it increases with the HNO_3 concentration and absorbed dose. The main radiolytic gases are N_2O and H_2, with volume fractions of(0.500–16.2) 9 10^(-2) and(1.30–11.8) 9 10^(-3), respectively, and they increase with the absorbed dose; the H_2 volume fraction decreases with increasing HNO_3 concentration. The main liquid radiolytic products are CH_3 COOH and HNO_2, and their concentrations are(3.40–19.7) 9 10^(-2) and(0.200–4.80) 9 10^(-3)-mol L^(-1), respectively, which increase with the HNO_3 concentration. Since a significant concentration of HNO_2 is present in the irradiated AHA-HNO_3 solution, a holding reductant must be used to destroy HNO_2 and stabilize Pu(Ⅲ) and Np(Ⅴ) when AHA is applied for the separation of Pu and Np from U.

Pathological effects of vanillic acid on urinary tract in rats with infectious calculi

Objective:The pathological changes of urinary tract were observed after the treatment of infectious stone by vanillic acid.Methods:40 male Wistar rats were randomly divided into blank control group,infectious stone group,vanillic acid group and acetohydroxamic acid group.Blank control group:4 male Wistar rats were fed without special treatment.Infectious Stone Group:12 male Wistar rats were implanted with 4 mm bacteria bearing foreign body in the front of the polyurethane vein indwelling needle infected with Proteus mirabilis into the bladder to induce the formation of infection stone.In the vanillic acid group,after the model were establishmented,12 male Wistar rats were treated with vanillic acid at 50mg/kg?d for 3 weeks.Acetohydroxamic acid group:after the model were establishmented,12 male Wistar rats were treated with acetohydroxamic acid at 12.5mg/kg?d for 3 weeks.The rats were killed 21 days later.The kidney,ureter and bladder were fixed in 10%paraformaldehyde solution for 24 hours.The specimens were embedded in paraffin,and the pathological analysis was carried out after HE and immunohistochemical staining.Results:In addition to the blank control group,the other three groups of rats had calculus formation in the bladder.No obvious pathological changes were found in the kidney,ureter and bladder in the blank control group,and inflammatory reactions were found in the other three groups:severe urinary tract inflammation was found in the infectious stone group,followed by acetylhydroxamic acid group.In the vanillic acid group,the pathological changes of urinary tract were the lightest,with a small amount of inflammatory cell infiltration and mucosal hyperplasia,but no serious pathological changes such as mucosal loss.The expression of Tamm-Horsfall Protein(THP)in the ascending branch of loop of Henle and the proximal part of distal tubule in vanillic acid group was not significant compared with that in the infectious stone group and acetohydroxamic acid group.Conclusion:Proteus mirabilis and its infective stones can lead to the damage of urinary epithelium.Vanillic acid can reduce the inflammatory lesions of urinary tissue.