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81.
    
In the present research, Fe3O4 and WS2 nanoparticles immobilized on or in KIT-6 (KIT: Korea Institute of Science and Technology) pores (KIT-6/WS2-Fe3O4) were synthesized and studied as a photocatalyst for degradation of representative chlorpyrifos as an organophosphorus pesticide. In addition, the KIT-6/WS2-Fe3O4 photocatalyst was characterized by different methods such as TEM, FESEM-EDS-Mapping, XRD, and N2 adsorption/desorption surface area, in order to understand their morphology, structural, and physical properties. The photocatalytic performance of this photocatalyst was investigated for degradation of chlorpyrifos by visible light irritation. The effects of variables such as chlorpyrifos concentration, KIT-6/WS2-Fe3O4 nanocatalyst amount, pH, and irradiation time on chlorpyrifos degradation efficiency was studied by central composite design with response surface methodology. The optimum conditions for CP degradation were obtained by 50 mg KIT-6/WS2-Fe3O4 nanocatalyst, and 7.2 ppm chlorpyrifos solution with pH = 6, at 52 min. The pseudo-first-order model with rate constants equal to 0.069 min−1 as best choice efficiency described the chlorpyrifos degradation process according to Langmuir-Hinshelwood kinetic.  相似文献   
82.
    
The purpose of this experiment was the green synthesis of silver nanoparticles from aqueous extracts of Ziziphora clinopodioides Lam (AgNPs@Ziziphora) and assessment of their cytotoxicity, antioxidant, antibacterial, antifungal, and cutaneous wound-healing effects. These nanoparticles were characterized using ultraviolet–visible spectroscopy (UV–Vis), X-ray diffraction (XRD), field emission scanning electron microscopy with energy-dispersive X-ray spectroscopy (FESEM-EDX), atomic force microscopy (AFM), and transmission electron microscopy (TEM). UV–Vis, TEM, and FESEM analyses indicated that the size of Ag nanoparticles (AgNPs) depended on Z. clinopodioides and AgNO3 concentrations. In vitro biological experiments indicated that AgNPs@Ziziphora has excellent antioxidant potential against DPPH, antifungal effects against Candida guilliermondii, Candida krusei, Candida glabrata, and Candida albicans, and antibacterial activities against Staphylococcus aureus, Bacillus subtilis, Streptococcus pneumonia, Salmonella typhimurium, Pseudomonas aeruginosa, and Escherichia coli O157:H7. Also, these nanoparticles did not exhibit cytotoxicity property against human umbilical vein endothelial cells (HUVECs). An in vivo biological test revealed that AgNPs@Ziziphora ointment significantly (p ≤ 0.01) increased the levels of wound contracture, blood vessels, hydroxyl proline, hexuronic acid, hexosamine, fibrocytes, fibroblasts, and fibrocyte/fibroblast ratio and significantly (p ≤ 0.01) decreased the wound area, and levels of total cells, neutrophils, and lymphocytes than other groups in rats. The results of UV–Vis, XRD, FESEM-EDX, AFM, and TEM confirmed that the aqueous extract of Z. clinopodioides can be used to produce silver nanoparticles with significant antioxidant, antimicrobial, and cutaneous wound-healing properties without any cytotoxicity.  相似文献   
83.
    
In this study, a green and high yielding synthesis of novel pyrazoline‐containing Schiff bases via a one‐pot pseudo five‐component condensation reaction under catalyst‐free conditions in EtOH at room temperature is described. Initially, the reaction of 1,1‐bis(methylthio)‐2‐nitroethylene (BMTNE), with NH2NH2.H2O is used for situ preparation of 1,1‐dihydrazino‐2‐nitroethylene (DHNE). Then, wide varieties of aldehydes are added to the mixture to afford the desired products good to excellent yields. This synthetic route is presented with several unique merits such as simplicity in operation and workup, readily presented starting materials, and high functional group tolerance. Additionally, the stoichiometric complex formation of these Schiff bases as ligand (L) with various metal ions [Mn(OAc)2, Cu(OAc)2 and Zn(OAc)2] in general molecular formula [ML] is examined via Job's method. Subsequently, theoretical analysis of the product is accomplished using density functional theory (DFT) calculations. According to the frontier molecular orbital (FMO) analysis, it is found that the aryl group linked to the imine bond contributes as an electron donor in the ligand–metal complex.  相似文献   
84.
    
In the present study a collagen-glycosaminoglycans scaffold, following chemical modifications, was prepared as an analog of the extracellular matrix (ECM) by a freeze drying method. Appropriate tests related to its use for wound healing (evaluation of the structure by scanning electron microscopy, swelling properties, biodegradability properties, Fourier transform infrared spectroscopy and cell culture) were done on the scaffolds. Amniotic fluid-derived stem (AFS) cell seeded scaffolds were shown to be potentially useful for wound healing.  相似文献   
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