Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticle...Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticles were chlorinated by NaClO solution to get AgCl@SiO_(2)/CTS‑based chloramine nano‑hybrid materials,denoted as AgCl@SiO_(2)/CTS‑Cl.A transmission electron microscope was used to observe the morphology of the as‑prepared samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.At the same time,an X‑ray diffractometer and an infrared spectroscope were utilized to characterize their crystal and chemical structures.Besides,ζpotentials were measured to elucidate the surface modification of AgCl nanoparticles by—NH_(2),the antibacterial mechanism of AgCl@SiO_(2)/CTS‑Cl was investigated by scanning electron microscopy,and Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were used as the to‑be‑tested strains to evaluate the antimicrobial activity of samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.Findings demonstrate that sample AgCl@SiO_(2)/CTS exhibits a chain‑like structure ascribed to the interaction between—NH_(2),and each AgCl@SiO_(2)/CTS hybrid nanoparticle contains several AgCl cores.In the meantime,sample AgCl@SiO_(2)/CTS‑Cl exhibits excellent antibacterial activity against E.coli and S.aureus,which is attributed to the synergistic antibacterial effect of Ag^(+)and Cl^(-).Sample AgCl@SiO_(2)/CTS‑Cl with a dosage of 640.00μg·mL^(-1) could completely kill the two kinds of tested bacteria in 12 h of incubation;it retains a high antibacterial efficiency even after 10 cycles of antibacterial tests.展开更多
为了明确多因素耦合作用下低钙高强水泥混凝土的性能退化机理,本文通过设置不同侵蚀因素(冻融-溶蚀、冻融-Cl^(-)侵蚀、溶蚀-Cl^(-)侵蚀、冻融-溶蚀-Cl^(-)侵蚀),结合外观变化、质量变化、超声波速率、Cl^(-)含量、物相组成测试等,研究...为了明确多因素耦合作用下低钙高强水泥混凝土的性能退化机理,本文通过设置不同侵蚀因素(冻融-溶蚀、冻融-Cl^(-)侵蚀、溶蚀-Cl^(-)侵蚀、冻融-溶蚀-Cl^(-)侵蚀),结合外观变化、质量变化、超声波速率、Cl^(-)含量、物相组成测试等,研究了低钙原料高强熟料水泥(Low-calcium raw material and high-strength clinker cement,LCHS)混凝土的损伤演化规律。结果表明:在冻融-溶蚀-Cl^(-)侵蚀耦合作用下,LCHS混凝土历经早期质量提升、中期Ca^(2+)溶蚀与盐结晶的动态平衡以及后期损害快速发展的过程,溶蚀-Cl^(-)侵蚀作用在早期和中期会降低LCHS混凝土的损伤;冻融-Cl^(-)侵蚀和冻融-溶蚀对LCHS混凝土的损伤基本高于冻融-溶蚀-Cl^(-)侵蚀;LCHS混凝土的耐久性能优于普通硅酸盐水泥混凝土。研究结果可以为寒冷地区、地下水或除冰盐环境下低钙高强水泥混凝土结构的设计、耐久性能评估及寿命预测提供参考。展开更多
文摘Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticles were chlorinated by NaClO solution to get AgCl@SiO_(2)/CTS‑based chloramine nano‑hybrid materials,denoted as AgCl@SiO_(2)/CTS‑Cl.A transmission electron microscope was used to observe the morphology of the as‑prepared samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.At the same time,an X‑ray diffractometer and an infrared spectroscope were utilized to characterize their crystal and chemical structures.Besides,ζpotentials were measured to elucidate the surface modification of AgCl nanoparticles by—NH_(2),the antibacterial mechanism of AgCl@SiO_(2)/CTS‑Cl was investigated by scanning electron microscopy,and Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were used as the to‑be‑tested strains to evaluate the antimicrobial activity of samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.Findings demonstrate that sample AgCl@SiO_(2)/CTS exhibits a chain‑like structure ascribed to the interaction between—NH_(2),and each AgCl@SiO_(2)/CTS hybrid nanoparticle contains several AgCl cores.In the meantime,sample AgCl@SiO_(2)/CTS‑Cl exhibits excellent antibacterial activity against E.coli and S.aureus,which is attributed to the synergistic antibacterial effect of Ag^(+)and Cl^(-).Sample AgCl@SiO_(2)/CTS‑Cl with a dosage of 640.00μg·mL^(-1) could completely kill the two kinds of tested bacteria in 12 h of incubation;it retains a high antibacterial efficiency even after 10 cycles of antibacterial tests.
文摘为了明确多因素耦合作用下低钙高强水泥混凝土的性能退化机理,本文通过设置不同侵蚀因素(冻融-溶蚀、冻融-Cl^(-)侵蚀、溶蚀-Cl^(-)侵蚀、冻融-溶蚀-Cl^(-)侵蚀),结合外观变化、质量变化、超声波速率、Cl^(-)含量、物相组成测试等,研究了低钙原料高强熟料水泥(Low-calcium raw material and high-strength clinker cement,LCHS)混凝土的损伤演化规律。结果表明:在冻融-溶蚀-Cl^(-)侵蚀耦合作用下,LCHS混凝土历经早期质量提升、中期Ca^(2+)溶蚀与盐结晶的动态平衡以及后期损害快速发展的过程,溶蚀-Cl^(-)侵蚀作用在早期和中期会降低LCHS混凝土的损伤;冻融-Cl^(-)侵蚀和冻融-溶蚀对LCHS混凝土的损伤基本高于冻融-溶蚀-Cl^(-)侵蚀;LCHS混凝土的耐久性能优于普通硅酸盐水泥混凝土。研究结果可以为寒冷地区、地下水或除冰盐环境下低钙高强水泥混凝土结构的设计、耐久性能评估及寿命预测提供参考。
