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长白山地区为保护较为完善的原始森林区,物种丰富,因此被选为论文的研究区域.这里地处温带,气候寒冷,水甲虫种类分布有着一定的独特性.该项研究通过对不同海拔高度的不同水体中水甲虫的采样,研究了长白山北坡水甲虫的种类、生物多样性及其颁与环境因子的相关性.通过调查和研究,发现长白山水甲虫已记录的种类共有8科37属67种,其中占种群优势的是龙虱科和水龟虫科.同时,通过对文献的系统研究,发现中国有已记录的水甲虫共21科141属916种,比原记录601种(杨集昆,1994)多215种.在对长白山北坡水甲虫区系研究的同时,对生物多样性指数进行了分析,结果表明长白山北坡的水甲虫生物多样性各项指标均显示出该地区水甲虫物种较为丰富,物种均匀度高.在研究水甲虫的分布与环境因子的关系时发现,不同水体中环境因子对水甲虫分布的影响不同,活水水体中起主要作用的因子是植被密度和水流速度,静水水体中起主要作用的因子是海拔和腐殖化程度.

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辅酶Q10存在于生物体呼吸链中,化学名称为2,3-二甲氧基-5-甲基-6-癸异戊烯基苯醌,是人体内存在的唯一泛酮类化合物,具有广泛的临床应用。本论文即应用微生物发酵法提取辅酶Q10以期为进一步扩大辅酶Q10生产规模提供基础理论和实验指导。本研究选择皂化抽提辅酶Q10结合高效液相色谱定量分析方法对文献报道的辅酶Q10产生菌进行筛选比较,最终选择根癌土壤杆菌AGR1.1416为出发菌株,对其进行诱变处理,筛选到酪氨酸、色氨酸双重营养缺陷的抗乙硫氨酸突变株AGR0610,产量达到31.42mg/L,比原始菌株提高了156.07%。通过单因素实验考察了碳源、氮源、初始pH值、接种量、装液量、温度和培养时间等发酵条件对一辅酶Q10产量的影响,结果表明,以葡萄糖和糖蜜为复合碳源,酵母膏和大豆蛋白陈为复合氮源,在30℃下,初始pH为7.0时,以7%的接种量接入到装有20OmL培养基的50OmL三角瓶中,培养72h,菌体生长良好,辅酶Q10产量可达到最大值。应用Placket-burman法对影响突变株AGR0610发酵产辅酶Q10的碳源、氮源和添加物等因素进行考察,表明糖蜜、大豆蛋白陈、蛋氨酸和玉米浆对辅酶Q10发酵有显著影响。应用响应曲面法对这四种因素的最佳取值水平范围和交互影响作用进行分析,结果表明,玉米浆与糖蜜、大豆蛋白陈之间的交互作用有显著影响,当糖蜜为1.02%,大豆蛋白陈为0.49%,蛋氨酸为0.34%,玉米浆为0.29%时,辅酶Q10有最大产量38.42mg/L。优化后的辅酶Q10产量比优化前提高了23.86%,达到国内先进水平。原始菌株经诱变,发酵条件优化使产量提高了215.69%。辅酶Q10粗提品经制备薄层层析分离纯化,结晶,得到辅酶Q10纯品,回收率达到90%以上。

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Controlled vertical drying deposition method was used to make high-quality single crystal close-packed colloidal films formed of different radii polystyrene latex spheres on glass substrates coming from a low concentration water suspension (0.1% volume fraction). Regardless of the spheres radii the film thickness was about 6.3 microns. However, cracks destroyed the crystalline film structure during the colloidal film growth. The effect of particle radius (85-215 nm range) on film cracking was systematically studied using in situ optical fracture monitoring. Primary parallel cracks run along the vertical growth direction, later followed by secondary branched cracks in-between the primary cracks due to residual water evaporation. Quantitative theoretical relationship between the cracks spacing and particles radius was derived and shows good agreement with experimental observations. Normalized cracks spacing is related to a reciprocal ratio of the dimensionless particle radius.