Photocatalytic performance of Ag₂S under irradiation with visible and near-infrared light and its mechanism of degradation

Ag2S has only rarely been investigated as a photocatalyst on its own, although it has been widely used as an important component of composite photocatalysts.</p

PMMA-Grafted Calcium Sulfate Whiskers for Applications as Fillers in PVC

Calcium sulfate whiskers (CSWs) were hydroxylated with a sodium hydroxide (NaOH) solution and isolated for subsequent treatment with an ethanolic 3-(methacryloxy)propyltrimethoxysilane (KH570) solution to introduce C=C double bonds on the CSWs’ surfaces. Then, CSW-g-PMMA was prepared by grafting polymethyl methacrylate (PMMA) onto the surface of modified CSW using in situ dispersion polymerization. The CSW-g-PMMA was used as a filler and melt-blended with polyvinyl chloride (PVC) to prepare PVC-based composites. The surface chemical structure, PMMA grafting rate, and hydrophobic properties of CSW-g-PMMA were analyzed using X-ray diffraction, diffuse reflectance Fourier-transform infrared spectroscopy, thermogravimetric analysis, and water contact angle measurements, respectively. The effects of the CSW-g-PMMA filler on the mechanical properties of the CSW-PMMA/PVC composites were also investigated. The results showed that NaOH treatment significantly increased the number of hydroxyl groups on the surface of the CSWs, which facilitated the introduction of KH570. PMMA was successfully grafted onto the KH570 with a grafting rate of 14.48% onto the surface of the CSWs. The CSW-g-PMMA had good interfacial compatibility and adhesion properties with the PVC matrix. The tensile, flexural, and impact strengths of the CSW-g-PMMA/PVC composite reached 39.28 MPa, 45.69 MPa, and 7.05 kJ/m2, respectively, which were 38.55%, 30.99%, and 20.10% higher than those of the CSW/PVC composite and 54.52%, 40.80%, and 32.52% higher than those of pure PVC, respectively. This work provides a new method for surface modification of inorganic fillers, resource utilization, and high value-added application of CSWs from phosphogypsum

Research on Protective Mechanism of Antioxidant Sodium Tanshinone&#8545;A Sulfonate on Erectile Function in Hyperlipidemia Rats

Objective: Sodium tanshinone &#8545;A sulfonate (STS) is recognized to be beneficial to oxidative stress (OS). However, it is unclear whether it protects erectile function by antioxidative stress and maintains the contractile phenotype of cavernosal smooth muscle cells (CCSMCs) in hyperlipidemia-induced erectile dysfunction (ED) rats. Therefore, this research aimed to assess the protective effect and the mechanism of STS on cavernous smooth muscle cells in hyperlipidemia-related ED. Methods: This study assessed erectile function using the intracavernous pressure (ICP)/mean arterial pressure (MAP) ratio. The phenotypic and oxidative-related markers were determined using western blot and immunohistochemistry assays. Sprague-Dawley rats were grouped as a normal control (NC) and four hyperlipidemia groups, including hyperlipidemia rats (HR), hyperlipidemia with saline (HR+NS), hyperlipidemia with 300 mg/kg N-acetylcysteine (HR+NAC), and hyperlipidemia rats with 10 mg/kg sodium tanshinone &#8545;A sulfonate (HR+STS). After 4 months, all rats were sacrificed for serum biochemistry, OS markers, and penile histologic examinations after ICP and MAP tests. Results: The ICP/MAP ratio was significantly higher in HR+STS and HR+NAC groups than in HR and HR+NS groups (p &lt; 0.05). Compared to the other hyperlipidemia rats, STS treatment markedly increased the expression of phenotypic proteins alpha-smooth muscle actin (&alpha;-SMA), smooth muscle myosin heavy chain (SMMHC), calponin, and Myocardin and decreased the osteopontin (OPN) expression in the penis (p &lt; 0.05). Furthermore, we demonstrated that STS increased SOD and GSH expression while reducing MDA expression in serum and corpus cavernosum tissues compared with the HR group. Conclusions: STS treatment protected the erectile function by reducing the OS and maintaining the contractile phenotype in the CCSMCs of the hyperlipidemia-induced ED rats

Silver Oxide as Superb and Stable Photocatalyst under Visible and Near-Infrared Light Irradiation and Its Photocatalytic Mechanism

Photocatalytic processes are an environmentally friendly technology for treatment of persistent organic pollutants. However, the majority of current photocatalysts cannot utilize sunlight sufficiently to realize fast decomposition of organic pollutants. In this research, a silver oxide nanoparticle aggregation with superb photocatalytic performance under artificial light source and sunlight was prepared and characterized. The results showed that methyl orange (MO) was decomposed completely in 120 s under irradiation of artificial visible light, artificial ultraviolet light, and sunlight, and in 40 min under near-infrared (NIR) light. The superb photocatalytic performance of as-prepared silver oxide remained almost constant after reuse or exposure under sunlight. It was confirmed that the co-working effect of photogenerated hole and ozone anion radicals did play an important role in the process of MO photodegradation with the existence of Ag₂O. The narrow band gap of Ag₂O, less than 1.3 eV, resulted in the photocatalytic performance of Ag₂O under NIR light. Furthermore, the high surface area and numerous crystal boundaries provided by the aggregation of Ag₂O nanoparticles efficiently increased the escape probability of photogenerated electrons and the contact probability of photogenerated holes with outside materials, assuring superb photocatalytic activity and excellent stability of as-prepared Ag₂O samples