ABSTRACT
Metal oxides can activate peroxymonosulfate (PMS) for the catalytic degradation of organic dyes. However, achieving high catalytic efficiency, structural stability, ease of recovery, and recyclability remains challenging for both research and practical applications. To address these requirements, a bimetallic oxide, CuMnO2, was synthesized using a simple hydrothermal approach and was encapsulated to create hydrogel beads, CS-Ca@PEI/CuMnO2. Subsequently, CS-Ca@PEI/CuMnO2 was used to activate PMS and establish a solid-liquid heterogeneous oxidation system (CS-Ca@PEI/CuMnO2/PMS) for the degradation of Congo red (CR). The effects of various parameters such as different systems, catalyst dosages, initial pH values, PMS concentrations, temperatures, and anion types on the catalytic degradation properties of CS-Ca@PEI/CuMnO2 for CR were systematically evaluated. The results indicated that CS-Ca@PEI/CuMnO2 has exceptional degradation capacity, achieving 91.0% degradation of CR at pH 7. After three degradation cycles, the catalyst maintained an 86.9% degradation efficiency compared to its original performance, highlighting its robust structural stability. The presence of reactive radicals, specifically 1O2 and â¢O2-, were confirmed through quenching experiments, X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance spectroscopy (EPR). Liquid chromatography-tandem mass spectrometry (LC-MS) revealed ten proposed intermediates in the catalytic degradation process. Due to its exceptional catalytic performance, structural durability, recyclability, and ease of retrieval, the catalyst shows great potential for effectively removing organic pollutants from industrial wastewater.
ABSTRACT
BACKGROUND: 60 Co-γ irradiation can simulate the effects of aging and enhance the flavor of distilled spirits. The present study aimed to investigate the effects of 0, 2, 4, 6, 8 and 10 kGy 60 Co-γ irradiation doses on the key aroma components in newly produced navel orange distilled spirits and thus determine the mechanism of their aging distilled spirits. RESULTS: The identification of aroma compounds demonstrated that ethyl hexanoate, d-limonene, ethyl octanoate, 3-methyl-1-butanol and linalool are the key aroma compounds in navel orange distilled spirits, which were increased except for linalool with irradiation doses of 2-6 kGy. Irradiation treatment simulated the effects of the aging of navel orange distilled spirits by promoting the content of total acids, total esters and aldehydes. Irradiation doses of 2-6 kGy increased the aroma intensity of navel orange distilled spirits, reaching an optimum at 6 kGy. However, irradiation doses as high as 8 and 10 kGy decreased the content of esters in navel orange distilled spirits, which led to a deterioration of the spirit flavor. CONCLUSION: Low doses of 60 Co-γ irradiation can simulate the effects of the aging by increasing the content of key aromatic compounds in navel orange distilled spirits. © 2023 Society of Chemical Industry.
Subject(s)
Citrus sinensis , Citrus sinensis/chemistry , Acyclic Monoterpenes , Odorants , EstersABSTRACT
BACKGROUND/AIMS: Endogenous parathyroid hormone (PTH) plays an important role in fracture healing. This study investigated whether endogenous PTH regulates fracture healing by bone morphogenetic protein (BMP) and/or the transforming growth factor-ß (TGF-ß) signaling pathway. METHODS: Eight-week-old wild-type (WT) and PTH-knockout (PTH KO) male mice were selected, and models of open right-femoral fracture were constructed. Fracture healing and callus characteristics of mice in the two groups were compared by X-ray, micro-computed tomography, histological, and immunohistochemical examinations. Bone marrow mesenchymal stem cells (BMMSCs) of 8-week-old WT and PTHKO male mice were obtained and induced into osteoblasts and chondrocytes. RESULTS: We found that expression levels of Runt-related transcription factor (RUNX2), bone morphogenetic protein-receptor-type â ¡ (BMPR2), phosphorylated Smad 1/5/8, and phosphorylated cyclic adenosine monophosphate-responsive element binding protein (CREB) in the callus of PTHKO mice were significantly decreased, whereas no significant difference in expression of SOX9, TGF-ßR2,or pSMAD2/3 was observed between PTHKO and WT mice. Additionally, the activity of osteoblast alkaline phosphatase was low at 7 days post-induction, and was upregulated by addition of PTH or dibutyryl cyclic adenosine monophosphate (dbcAMP) to the cell culture. Furthermore, H89 (protein kinase A inhibitor)eliminated the simulating effects of PTH and dbcAMP, and a low concentration of cyclic adenosine monophosphate (cAMP) was observed in PTHKO mouse BMMSCs. CONCLUSION: These results suggested that endogenous PTH enhanced BMPR2 expression by a cAMP/PKA/CREB pathway in osteoblasts, and increased RUNX2 expression through transduction of the BMP/pSMAD1/5/8 signaling pathway.
