开展陕甘宁红色旅游流网络结构特征研究,可以指导目的地旅游网络结构优化,推动红色旅游高质量发展。运用地理信息技术系统(geographic information system,GIS)技术、社会网络分析等方法,对陕甘宁红色旅游流整体网络特征、网络节点特征...开展陕甘宁红色旅游流网络结构特征研究,可以指导目的地旅游网络结构优化,推动红色旅游高质量发展。运用地理信息技术系统(geographic information system,GIS)技术、社会网络分析等方法,对陕甘宁红色旅游流整体网络特征、网络节点特征进行系统研究。结果表明,陕甘宁红色旅游流网络结构松散,密度低,呈现典型的“核心-边缘”特征;红色旅游流网络凝聚特征显著,地域集中性强,跨区域合作有待强化;延安革命纪念馆等关键节点功能地位突出,网络极化效应显著;核心节点对周边节点存在“虹吸效应”。研究进一步从构建多极化红色旅游流网络体系、推动红色旅游与相关业态协调发展和创新融合等方面就推动陕甘宁红色旅游流网络优化提出了相关对策建议。展开更多
The use of tetra-substituted ammo aluminum phthalocyanine (TAAIPc) as a new red-region fluorescent substrate for horseradish peroxidase (HRP)-based enzyme-linked immunosorbent assay was investigated. TAAIPc displayed ...The use of tetra-substituted ammo aluminum phthalocyanine (TAAIPc) as a new red-region fluorescent substrate for horseradish peroxidase (HRP)-based enzyme-linked immunosorbent assay was investigated. TAAIPc displayed an excitation maximum at 610 nm and emission maximum at 678 nm in a strong acidic medium. In the presence of HRP, trace amounts of H2O2 could rapidly and significantly react with TAAIPc, thus quenching the fluorescence of TAAIPc. The Michaelis-Menten parameters Km and Vmax were measured to be 2.82 × 10?6 mol/L?1 and 6.0 × 10?9 mol·L?1, respectively. In this paper, TAAIPc was used in an HRP-based enzyme-linked immunosorbent assay (ELISA) of α-fetoprotein (AFP) in human serum with satisfactory results. AFP could be determined in the concentration range of 0.5–200 ng/mL with a detection limit of 0.2 ng/mL, which was close to that of radioimmunoassay. The advantage of proposed method was strongly minimizing the interference resulting from background fluorescence or scattering light and had a high analytical sensitivity.展开更多
文摘开展陕甘宁红色旅游流网络结构特征研究,可以指导目的地旅游网络结构优化,推动红色旅游高质量发展。运用地理信息技术系统(geographic information system,GIS)技术、社会网络分析等方法,对陕甘宁红色旅游流整体网络特征、网络节点特征进行系统研究。结果表明,陕甘宁红色旅游流网络结构松散,密度低,呈现典型的“核心-边缘”特征;红色旅游流网络凝聚特征显著,地域集中性强,跨区域合作有待强化;延安革命纪念馆等关键节点功能地位突出,网络极化效应显著;核心节点对周边节点存在“虹吸效应”。研究进一步从构建多极化红色旅游流网络体系、推动红色旅游与相关业态协调发展和创新融合等方面就推动陕甘宁红色旅游流网络优化提出了相关对策建议。
文摘The use of tetra-substituted ammo aluminum phthalocyanine (TAAIPc) as a new red-region fluorescent substrate for horseradish peroxidase (HRP)-based enzyme-linked immunosorbent assay was investigated. TAAIPc displayed an excitation maximum at 610 nm and emission maximum at 678 nm in a strong acidic medium. In the presence of HRP, trace amounts of H2O2 could rapidly and significantly react with TAAIPc, thus quenching the fluorescence of TAAIPc. The Michaelis-Menten parameters Km and Vmax were measured to be 2.82 × 10?6 mol/L?1 and 6.0 × 10?9 mol·L?1, respectively. In this paper, TAAIPc was used in an HRP-based enzyme-linked immunosorbent assay (ELISA) of α-fetoprotein (AFP) in human serum with satisfactory results. AFP could be determined in the concentration range of 0.5–200 ng/mL with a detection limit of 0.2 ng/mL, which was close to that of radioimmunoassay. The advantage of proposed method was strongly minimizing the interference resulting from background fluorescence or scattering light and had a high analytical sensitivity.