Interaction of catechins with aluminum in vitro

Tea is one of the most popular beverages, consumed by over two thirds of the world's population; but the aluminum accumulation property of tea plant is becoming the focus of many researches because of aluminum's known adverse effect on human health. Investigation of the interactions of catechins with Al(3+) showed that during the interaction of catechins with Al(3+), the UV-vis spectrum of catechins was changed. Absorption of EGCG at 274 nm decreased and increased at 322 nm; EC and C's at 278 nm changed little. The ratio of Al(3+) to EGCG was 1:1 in pH 5.0 buffer solution; in pH 6.2 buffer solution, the ratio in the Al-EGCG complex was 1:1. Interestingly, while the ratio reached to over 2, after the complex of Al-EGCG started polymerization, the ratio in the polymer was 2:1. In pH 6.2 buffer solution, the complex behavior of C with Al(3+) was the same as that of EGCG, with a little difference for EC. When the ratio of Al(3+) to EC was <1, the complex in ratio was 1:2, but, the complex polymerized when the ratio of Al(3+) to EC was >1. It was found that the ratio of Al(3+) to EC in the polymer was 1:1. Polymerization of Al-catechin complexes might reduce aluminum absorption in the intestine. Kow value was also employed to study the properties of aluminum species in tea infusion (at gastric and intestine pH condition) and the effect of catechins and tea polyphenols on Kow in buffer solution. Results showed that Kow value rose much higher at the intestine pH than at the gastric pH. Tea polyphenols and catechins could greatly reduce aluminum Kow value in acetic buffer, indicating that these compounds may reduce aluminum absorption during tea intake.     

脉冲电晕等离子体烟气脱硫工业试验研究

利用建造在四川绵阳科学城热电厂的最大烟气处理量为20 000 m3/h的脉冲电晕等离子体烟气脱硫工业中试装置,研究了影响脱硫效率的因素,获得了最佳工艺参数。究结果表明,当烟气温度在65～70℃,烟气水分含量约10％,氨硫化学剂量比为1∶1,烟停留时间大于6 s、能耗低于5 Wh/Nm+3等条件下,脱硫率达85％以上。     

HPAM／AlCit交联聚合物溶液微孔膜过滤行为研究

分别采用孔径为1．2μm醋酸纤维素树脂核微孔滤膜及2μm混合纤维素树脂热压滤膜,考察了HPAM／AlGit交联聚合物溶液在恒压并流微过滤条件下的微孔膜过滤行为。结果表明,随反应时间的延长,该交联聚合物溶液中交联聚合物线团的数目逐渐增加,对于核微孔滤膜,其封堵作用遵循表面过滤机理,侧重反映封堵过程中交联聚合物线团的粒子特性;而对于网络型热压滤膜,过滤实验中交联聚合物线团对滤膜的封堵作用逐步由深度过滤过渡到表面过滤,侧重反映交联聚合物线团封堵非均—孔径滤膜所具有的非均匀封堵特征,即遵循大孔到中孔到小孔的封堵过程。     

用于周期复振荡研究的微分方程解的一个结果*

提出了“组合优势条件”,并用其发民服Ｓ．Ｂａｎｋ和Ｊ．Ｌａｎｇｌｅｙ于１９９２年证明了的用于周期复振荡研究的一个重要结果,大大扩充了其适用性。     

论中国农村发展的"瓶颈"

文章从伦理文化的宏观角度分析了农村发展的问题所在,并提供了方向上的建议.     

纯硅芯石英光纤的研制

结合改进的化学汽相沉积(MCVD)法的特点, 设计纯硅芯石英光纤最佳折射率剖面结构, 并对采用改进的石墨炉加热的MCVD法制备纯硅芯石英光纤预制棒和拉丝工艺进行讨论. 分析了制作工艺中内包层掺氟量的提高、内包层厚度增加和纤芯折射率保持等难点的原理, 并给出了解决方案. 同时给出了制备的纯硅芯石英光纤预制棒的折射率剖面图和拉制成型的纯石英光纤折射率剖面图.     

辽宁工业旅游的SWOT分析及开发对策

辽宁省工业旅游资源丰富，大力发展工业旅游，既能丰富旅游内涵，又可加快辽宁老工业基地振兴的步伐．本文通过对辽宁工业旅游的SWOT分析，认为辽宁工业旅游既有优势、机会，也存在劣势和威胁，只有抓住机遇，迎接挑战，采取措施，才能使辽宁省的工业旅游实现可持续发展，从而为老工业基地的振兴做出贡献．     

濮阳市规模以上工业企业技术创新能力现状及对策研究

<正>建设创新型国家是新时期党中央做出的一项重大战略决策,河南省委、省政府也做出了增强自主创新能力、建设创新型河南的重要决定,以实现经济的跨越式发展。为构建具有濮阳特色的区域创新体系,培养一批具有自主知识产权的骨干企业,建设创新型濮阳,濮阳市科学技术局、濮阳市发改委、濮阳市企业服务局联合开展了濮阳市规模以上工业企业技术创新能力调查,旨在摸清濮阳市企业技术创新能力现状,为推动濮阳区域经济发展、全面建设创新型濮阳提供参考依据。     

球墨铸铁热浸镀铝的抗氧化性

为了延长铸铁工件的使用寿命,采用熔剂法将墨铸铁热浸镀铝,对镀层截面进行了形貌观察(SEM)、能谱分析(EDS)和衍射分析(XRD),测试了镀层的抗氧化性.结果表明,镀层由表面富铝层及扩散层构成,富铝层包含降温形成的针状FeAl3相,扩散层由FeAl3,Fe2Al5 物相组成,其形态呈舌状,并嵌入基体;氧化时镀层全部转变为扩散层,并能保持非常缓慢的退化速度,使球墨铸铁的抗氧化性显著提高.     

高新区92家工业企业自主创新调查研究

2006年杭州高新区工业企业研发投入(R&D)23.1亿元,占全区研发投入的82.0%,工业企业已成为全区自主创新的主体.为把握高新区工业企业技术创新现状,了解企业在实施技术创新战略中遇到的困难和阻碍.