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比色法测碘酸铜溶度积常数实验的改进
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作者 丁子都 雷英杰 +3 位作者 梁云 李襄宏 王炎英 黄涛 《大学化学》 CAS 2023年第12期257-261,共5页
现行教材中以氨水做显色剂,比色法测定碘酸铜溶度积常数,有一定的环境污染。本实验以甘氨酸替代氨水作为显色剂,通过紫外-可见吸收光谱考察甘氨酸与铜离子反应的时间以及甘氨酸的最佳用量,从而获得配制甘氨酸合铜(Ⅱ)溶液的最佳条件,进... 现行教材中以氨水做显色剂,比色法测定碘酸铜溶度积常数,有一定的环境污染。本实验以甘氨酸替代氨水作为显色剂,通过紫外-可见吸收光谱考察甘氨酸与铜离子反应的时间以及甘氨酸的最佳用量,从而获得配制甘氨酸合铜(Ⅱ)溶液的最佳条件,进而测定该条件下配制的各溶液的吸光度,最终获得碘酸铜饱和溶液中铜离子的浓度并计算得到与文献值接近的溶度积常数。该实验可避免实验过程中挥发性腐蚀性气体的释放,且溶液可浓缩回收甘氨酸合铜(Ⅱ),避免了环境污染,是一种绿色实验方法,在人数众多的基础实验教学中具有适用性。 展开更多
关键词 碘酸铜 溶度积常数 比色法
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Multi-factor high-order intuitionistic fuzzy timeseries forecasting model 被引量:1
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作者 Ya'nan Wang yingjie lei +1 位作者 Yang lei Xiaoshi Fan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第5期1054-1062,共9页
Fuzzy sets theory cannot describe the neutrality degree of data, which has largely limited the objectivity of fuzzy time series in uncertain data forecasting. With this regard, a multi-factor highorder intuitionistic ... Fuzzy sets theory cannot describe the neutrality degree of data, which has largely limited the objectivity of fuzzy time series in uncertain data forecasting. With this regard, a multi-factor highorder intuitionistic fuzzy time series forecasting model is built. In the new model, a fuzzy clustering algorithm is used to get unequal intervals, and a more objective technique for ascertaining membership and non-membership functions of the intuitionistic fuzzy set is proposed. On these bases, forecast rules based on multidimensional intuitionistic fuzzy modus ponens inference are established.Finally, contrast experiments on the daily mean temperature of Beijing are carried out, which show that the novel model has a clear advantage of improving the forecast accuracy. 展开更多
关键词 时间序列预测模型 模糊集理论 高阶 模糊聚类算法 模糊假言推理 不确定数据 直觉模糊集 日平均温度
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Adaptive partition intuitionistic fuzzy time series forecasting model
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作者 Xiaoshi Fan yingjie lei Yanan Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第3期585-596,共12页
To enhance the accuracy of intuitionistic fuzzy time series forecasting model, this paper analyses the influence of universe of discourse partition and compares with relevant literature. Traditional models usually par... To enhance the accuracy of intuitionistic fuzzy time series forecasting model, this paper analyses the influence of universe of discourse partition and compares with relevant literature. Traditional models usually partition the global universe of discourse, which is not appropriate for all objectives. For example,the universe of the secular trend model is continuously variational.In addition, most forecasting methods rely on prior information, i.e.,fuzzy relationship groups(FRG). Numerous relationship groups lead to the explosive growth of relationship library in a linear model and increase the computational complexity. To overcome problems above and ascertain an appropriate order, an intuitionistic fuzzy time series forecasting model based on order decision and adaptive partition algorithm is proposed. By forecasting the vector operator matrix, the proposed model can adjust partitions and intervals adaptively. The proposed model is tested on student enrollments of Alabama dataset, typical seasonal dataset Taiwan Stock Exchange Capitalization Weighted Stock Index(TAIEX) and a secular trend dataset of total retail sales for social consumer goods in China. Experimental results illustrate the validity and applicability of the proposed method for different patterns of dataset. 展开更多
关键词 intuitionistic fuzzy SET time series forecasting VECTOR OPERATOR MATRIX order deciding ADAPTIVE PARTITION
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