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CuCl分子的兰区谱带与振动温度
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作者 陆志刚 郑康成 杨广杰 《高等学校化学学报》 SCIE EI CAS 1986年第8期707-710,共4页
本文从几种钢盐在不同含氯氧化剂情况下进行固相燃烧时产生的CuCl^(*)分子的兰区谱带出发,测定了振动温度,对振动温度与谱带分布的关系进行了探讨,讨论了氧化剂对兰焰品质的影响。
关键词 振动温度 CUCL 谱带 氧化剂 分子
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农业灯诱害虫图像识别的模型算法研究
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作者 邱钊宏 郑康诚 +2 位作者 李嘉明 董润立 王建斌 《河南科技》 2024年第10期27-31,共5页
【目的】采用Faster R-CNN算法对样本数量少且分布不均衡的28类农田害虫数据集进行研究。【方法】首先,分析不同输入图像尺寸对训练模型性能的影响,确定了输入图像尺寸5472×3648的25%作为优选;其次,为了避免部分类别害虫因数据过... 【目的】采用Faster R-CNN算法对样本数量少且分布不均衡的28类农田害虫数据集进行研究。【方法】首先,分析不同输入图像尺寸对训练模型性能的影响,确定了输入图像尺寸5472×3648的25%作为优选;其次,为了避免部分类别害虫因数据过少而导致的过拟合问题,采用Mixup和mosaic方法增加数据多样性,并使用迁移学习提高模型性能。【结果】这些方法可以有效地提高模型的泛化性和鲁棒性,除了9与10这两类害虫相似度非常高导致AP值较低外,其余害虫识别的AP平均值为92.07%。【结论】通过测试数据检验模型的泛化性,发现模型表现良好但仍有改进空间。 展开更多
关键词 害虫识别 数据增强 Faster R-CNN 深度学习 目标检测
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Study of transient luminescence of three kinds of Ru complexes bound to DNA 被引量:1
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作者 ZHU WeiLing LIU XueWen +5 位作者 WANG Hui YU HuiJuan LI Aizheng CHAO Hui zheng kangcheng JI LiangNian 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2008年第2期133-139,共7页
The transient luminescence of three kinds of ruthenium complexes [Ru(bpy)2(7-CH3-dppz)]2+, [Ru(bpy)2(7-F-dppz)]2+ and [Ru(phen)2(7-F-dppz)]2+ bound to calf thy-mus DNA (ctDNA) has been studied by using the time-resolv... The transient luminescence of three kinds of ruthenium complexes [Ru(bpy)2(7-CH3-dppz)]2+, [Ru(bpy)2(7-F-dppz)]2+ and [Ru(phen)2(7-F-dppz)]2+ bound to calf thy-mus DNA (ctDNA) has been studied by using the time-resolved spectroscopy. The results show that the luminescence is due to the radiative decay from the charge-transfer states to the ground state. By the interaction with DNA, the radia-tiveless rate of the photoexcited Ru complex molecules decreases, which results in the increase of luminescence lifetime and efficiency. The structure of the Ru com-plex has an important impact on the interaction with DNA. The [Ru(bpy)2(7-CH3-dppz)]2+ shows the longest luminescence lifetime (about 382 ns), while the [Ru(bpy)2(7-F-dppz)]2+ shows the shortest lifetime (about 65 ns). The possible origin of the luminescence dynamics is discussed. 展开更多
关键词 ULTRAFAST photoelectronics TRANSIENT LUMINESCENCE DNA and Ru complex ULTRAFAST SPECTROSCOPIC technology
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A QSAR study and molecular design of benzothiazole derivatives as potent anticancer agents
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作者 CHEN JinCan QIAN Li +2 位作者 SHEN Yong CHEN LanMei zheng kangcheng 《Science China Chemistry》 SCIE EI CAS 2008年第2期111-119,共9页
A quantitative structure-activity relationship (QSAR) of a series of benzothiazole derivatives showing a potent and selective cytotoxicity against a tumorigenic cell line has been studied by using the density function... A quantitative structure-activity relationship (QSAR) of a series of benzothiazole derivatives showing a potent and selective cytotoxicity against a tumorigenic cell line has been studied by using the density functional theory (DFT), molecular mechanics (MM+) and statistical methods, and the QSAR equation was established via a correlation analysis and a stepwise regression analysis. A new scheme determining outliers by “leave-one-out” (LOO) cross-validation coefficient (q n-i 2 ) was suggested and successfully used. In the established optimal equation (excluding two outliers), the steric parameter (MR R) and the net charge (Q FR) of the first atom of the substituent (R), as well as the square of hydrophobic parameter (IgP)2 of the whole molecule, are the main independent factors contributing to the anticancer activities of the compounds. The fitting correlation coefficient (R 2) and the cross-validation coefficient (q 2) values are 0.883 and 0.797, respectively. it indicates that this model has a significantly statistical quality and an excellent prediction ability. Based on the QSAR studies, 4 new compounds with high predicted anticancer activities have been theoretically designed and they are expected to be confirmed experimentally. 展开更多
关键词 QSAR ANTICANCER activity BENZOTHIAZOLE DERIVATIVE DFT polarity interference
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