谁影响我们?我们又影响谁?——我国新闻传播学学科内与学科间互引的网络分析

本研究运用社会网络分析法,先对我国新闻传播学15本核心期刊学科内互引网络进行分析,探究新闻传播学科内部的知识交流结构与动向,分析发现新闻传播学科内部期刊之间互引较为普遍,但每本期刊的自我引用率与国际期刊相比偏低,这可能与我国期刊在研究主题上偏综合化而非特色化有关;此后,本文根据这15本核心期刊与其他学科核心期刊的互引网络,探寻新闻传播学科与其他学科知识产出的相互影响。结果表明,出版、教育综合、戏剧电影与电视艺术是与新闻传播学期刊互动最为频繁的几个学科,它们共同形成了一个双向高频互引群体,其他学科在与新闻传播学科互动的过程中则形成了主题单一的聚类

Effect of Sodium D-Gluconate-Based Inhibitor in Preventing Corrosion of Reinforcing Steel in Simulated Concrete Pore Solutions

应用电化学技术,结合扫描电子显微镜(SEM)观测,研究d-葡萄糖酸钠、钼酸钠和硫脲三组分复合缓蚀剂对模拟混凝土孔隙液中钢筋腐蚀行为的影响及其阻锈作用.结果表明:在含3.5%(W)nACl的模拟混凝土孔隙液中,复合缓蚀剂具有协同效应,对钢筋有良好的阻锈作用.当d-葡萄糖酸钠、钼酸钠和硫脲浓度分别为750、250和500Mg·l-1时,对钢筋的缓蚀效率可达到94.5%.应用软硬酸碱(HSAb)理论分析缓蚀机理,可认为三组分复合缓蚀剂在钢筋表面共同形成保护膜而阻止钢筋的腐蚀.The corrosion behavior of reinforcing steel in simulated concrete pore solutions with and without corrosion inhibitors was studied by electrochemical techniques and scanning electron microscopy(SEM).A combined inhibitive effect of sodium D-gluconate,Na2MoO4 and thiourea on restraining the corrosion of reinforcing steel immersed in the solution was observed.This result showed that there was a synergetic effect among the three agents in corrosion prevention.After adding the compound inhibitor(750 mg · L-1 sodium D-gluconate,250 mg · L-1 Na2MoO4,500 mg · L-1 thiourea) into the simulated concrete pore solution containing 3.5%(w) NaCl,the inhibition efficiency of the compound inhibitor was 94.5%.According to the Hard and soft acids and bases(HSAB) theory,the compound inhibitor worked by forming a protective film on the steel surface.国家自然科学基金(21073151;21173177;50731004;21021002)资助项---

Effect of pH on the electrochemical corrosion behavior of reinforcing steel in simulated concrete pore solutions

通讯作者：杜荣归 作者简介：唐方苗(1985-)，男，安徽安庆人，在读硕士，师承杜荣归教授，从事腐蚀电化学研究。[中文摘要]应用极化曲线法和电化学阻抗技术,结合扫描电子显微镜方法,测试钢筋在模拟混凝土孔隙液中的钝化与去钝化行为,以及溶液pH值对钢筋电化学腐蚀行为的影响作用。结果表明,钢筋在pH值为12.50的模拟液中处于钝态,随着溶液pH值的降低,钢筋的耐蚀性下降。钢筋表面去钝化发生腐蚀的临界pH值在11.12～11.05范围内。[英文摘要]The passivation and depassivation behavior of reinforcing steel in simulated concrete pore solutions(SPS) with different pH values was studied by the polarization curves,electrochemical impedance spectroscopy and scanning electron microscopy.The results indicated that reinforcing steel was in the passive state in the simulated concrete pore solution with pH 12.50.The lower the pH value of solutions,the more unstable the passive film of reinforcing steel.The critical pH value for the localized corrosion of the reinforcing steel in the simulated concrete pore solutions was between 11.12 and 11.05 based on the electrochemical measurements.国家自然科学基金资助项目(20473066);国家自然科学基金重点资助项目(50731004);国家科技支撑计划资助项目(2007BAB27B04

天津团泊洼水库水体生物生产力与渔业开发利用

天津市团泊洼水库属华北平原滨海盐碱性水库。1989年多学科综合调查的结果表明:该水体中营养盐类含量氮高磷低,挺水植物藨草、芦苇为主要初级生产者,浮游生物种类贫乏,现存量不高,周丛生物丰富。结果还表明,该水体仍有较大渔产潜力。应从调整鱼类种群结构着手,充分而合理地利用水体中的可更新资源,使渔业、环境协调发展