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梯度共聚物结构量瞬时值与累积值间关系的核磁及模拟研究
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作者 徐亮 秦雪莲 张以群 《安徽师范大学学报(自然科学版)》 CAS 2008年第2期150-154,162,共6页
用核磁和计算机模拟两种方法研究了梯度共聚物的结构量(组成,三元组浓度,序列长度分布)的瞬时值与累积值之间的关系,通过这两种方法验证了组成的瞬时值与累积值之间的传统关系式同样适用于三元组浓度、序列长度分布的瞬时值和累积值间... 用核磁和计算机模拟两种方法研究了梯度共聚物的结构量(组成,三元组浓度,序列长度分布)的瞬时值与累积值之间的关系,通过这两种方法验证了组成的瞬时值与累积值之间的传统关系式同样适用于三元组浓度、序列长度分布的瞬时值和累积值间的关系,梯度共聚物结构量的瞬时值和累积值可用此关系式关联. 展开更多
关键词 梯度共聚物 瞬时结构量 累积结构量 元组浓度 链段分布
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Effects of Ca2+concentrations on accumulations of mineral elements in the components of Pteroceltis tatarinowii 被引量:4
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作者 方升佐 候常英 洑香香 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第1期46-50,94,共页
The bark of Pteroceltis tatarinowii is a raw material for manufacturing Xuan Paper. The effects of Ca2+ concentrations on the accumulation of mineral elements in the bark, leaf and root of Pteroceltis tatarinowii were... The bark of Pteroceltis tatarinowii is a raw material for manufacturing Xuan Paper. The effects of Ca2+ concentrations on the accumulation of mineral elements in the bark, leaf and root of Pteroceltis tatarinowii were studied under controlled condi-tions. The types of Hoagland nutrient solution with three Ca2+ concentrations levels (200, 400 and 600 靏g-1) and a control (without Ca2+) were designed to culture Pteroceltis tatarinowii. After 6 months, contents of seven mineral elements including Ca, K, Mg, Mn, Zn, Cu and Na in the root, leaf and bark were analyzed. The results indicated that Ca accumulations content in the root, leaf and bark had positively relation with Ca2+ concentrations (200, 400, 600 靏g-1), and the order of the Ca content in the three components was root】leaf】bark. Ca content in the root treated with 600 靏g-1 Ca2+ concentrations was 5.5 times as high as that of the control, and about 1.4 times as high as that of the root treated in 200 and 400 靏/g Ca2+ concentrations respectively. On the contrary, K and Mg contents in the root, leaf and bark were negatively related to Ca2+ concentrations, especially in the bark, and their accumulation trend followed the order of leaf】root】bark. K content in the bark treated with 600 靏g-1 Ca2+ con-centrations was 39.3% of that of the control, and was 79.0% and 91.8% of that of the bark treated with 200 靏g-1 and 400靏g-1 Ca2+ concentrations respectively; Mg content in the bark treated with 600 靏g-1 Ca2+ concentrations was 23.4% of that of the control, and was 27.1% and 35.4% of that of the bark treated with 200 and 400 靏g-1 Ca2+ concentrations respectively. Com-pared with the control, the general tendency of Mn, Zn and Cu content decreased with increasing of Ca2+ concentrations and their contents were in the order: root】leaf】bark. Based on the results of this study, the experiment has been useful for providing academic bases in improving the bark quality of Pteroceltis tatarinowii on non-limestone soil. 展开更多
关键词 Pteroceltis tatarinowii Hoagland nutrient solution Ca2+ concentrations Mineral element COMPONENT
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活性自由基共聚物的微组成与微序列结构的计算机模拟 被引量:2
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作者 戴威 李红娟 +2 位作者 李书静 谢美然 张以群 《计算机与应用化学》 CAS CSCD 北大核心 2009年第2期157-160,共4页
为了研究活性自由基共聚物的组成、平均段长、链段分布及各元组浓度等重要结构量,本文运用Monte Carlo模拟方法设计一个计算机程序,模拟具有休眠-活化过程的活性自由基共聚过程,并分析所得到的链结构及微结构相关参数,确定了反应参数和... 为了研究活性自由基共聚物的组成、平均段长、链段分布及各元组浓度等重要结构量,本文运用Monte Carlo模拟方法设计一个计算机程序,模拟具有休眠-活化过程的活性自由基共聚过程,并分析所得到的链结构及微结构相关参数,确定了反应参数和聚合物产物结构的关系。 展开更多
关键词 MONTE CARLO模拟 活性自由基共聚物结构 元组浓度 共聚组成 休眠-活化
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