期刊文献+
共找到3篇文章
< 1 >
每页显示 20 50 100
论如何通过设计性实验提升学生的综合创新能力——以分光光度法同时测定维生素C和维生素E为例 被引量:1
1
作者 王靖宇 王蘅 +2 位作者 熊辉 陈志飞 原弘 《大学化学》 CAS 2020年第9期76-82,共7页
分光光度法同时测定维生素C和维生素E是一个典型的多组分同时测定实验,但是目前的测试体系对维生素C测定的误差较大(13.65%)。本文基于维生素C和维生素E的分子结构特征,剖析了影响维生素C测试准确度的原因,通过对测试体系进一步优化设... 分光光度法同时测定维生素C和维生素E是一个典型的多组分同时测定实验,但是目前的测试体系对维生素C测定的误差较大(13.65%)。本文基于维生素C和维生素E的分子结构特征,剖析了影响维生素C测试准确度的原因,通过对测试体系进一步优化设计与改进,将测试误差降低至1.98%,实验证明改进后的方法准确度高、重现性好、结果更可靠。以此设计性实验为例,可多方面训练学生针对实际问题并结合理论知识优化实验设计方案,提高综合创新能力。 展开更多
关键词 同时测定 维生素C 维生素E 分光光度法 综合创新能力
下载PDF
Analysis of the distribution characteristics of enterovirus types based on environmental surveillance from 2013 to 2021 in Fujian Province, China 被引量:2
2
作者 Xiuhui Yang Shaojian Cai +14 位作者 Xiaoqian Wu Yong Zhang Dong Li Yahong chen Qianjing chen Shuangli Zhu Dongmei Yan Wenbo Xu Hairong Zhang zhifei chen Suhan Zhang Yong Zhou Mengping Zhang Ningxuan Zheng Na You 《Biosafety and Health》 CAS CSCD 2023年第4期240-249,共10页
Environmental surveillance (ES) is a useful approach for monitoring circulating viruses, including polioviruses (PVs) and non-polio enteroviruses (NPEVs). In this study, the results of nine years of ES from 2013 to 20... Environmental surveillance (ES) is a useful approach for monitoring circulating viruses, including polioviruses (PVs) and non-polio enteroviruses (NPEVs). In this study, the results of nine years of ES from 2013 to 2021 at six sampling sites in three cities in Fujian Province, China, were summarized. It showed that the sewage samples contained abundant viruses, but the positive rate was affected by different sampling sites. From the 520 samples, 431 PVs, 1,713 NPEVs, and 281 human adenoviruses (HAdVs) were isolated. PV isolates had been markedly affected following the adjustment of the immunization strategy. All but one PV isolate were Sabin-like strains without wild PVs. One isolate was vaccine-derived PV type 3 with 10 variation points in theVP1 region. After May 2016, PV type 2 was no longer detected, and PV type 3 became a superior serotype. Of 1,713 NPEVs, 24 serotypes were identified, including echovirus11 (E11), E6, coxsackievirus B3 (CVB3), CVB5, E7, and E3 were the predominant serotypes (37.65%, 20.96%, 11.50%, 8.87%, 8.23%, and 7.06%, respectively). The temporal dynamic of the six common serotypes was inconsistent. E3 was frequently isolated, but the number of isolates was low, with no obvious peaks. E6, E7, and CVB3 exhibited periodic changes with a high peak every three to four years, and E11 only had one high peak lasting four years. Summer-fall peaks of the echoviruses and spring-winter peaks of CVB were observed in the monthly distribution of virus isolation. The infectious isolates of various serotypes of different species identified from the sewage samples showed that ES is an essential part of pathogen surveillance. 展开更多
关键词 Enterovirus surveillance Enteroviruse POLIOVIRUS Distribution characteristics
原文传递
Empirical analysis of network measures for predicting high severity software faults 被引量:4
3
作者 Lin chen Wanwangying MA +4 位作者 Yuming ZHOU Lei XU Ziyuan WANG zhifei chen Baowen XU 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第12期198-215,共18页
Network measures are useful for predicting fault-prone modules. However, existing work has not distinguished faults according to their severity. In practice, high severity faults cause serious problems and require fur... Network measures are useful for predicting fault-prone modules. However, existing work has not distinguished faults according to their severity. In practice, high severity faults cause serious problems and require further attention. In this study, we explored the utility of network measures in high severity faultproneness prediction. We constructed software source code networks for four open-source projects by extracting the dependencies between modules. We then used univariate logistic regression to investigate the associations between each network measure and fault-proneness at a high severity level. We built multivariate prediction models to examine their explanatory ability for fault-proneness, as well as evaluated their predictive effectiveness compared to code metrics under forward-release and cross-project predictions. The results revealed the following:(1) most network measures are significantly related to high severity fault-proneness;(2) network measures generally have comparable explanatory abilities and predictive powers to those of code metrics; and(3) network measures are very unstable for cross-project predictions. These results indicate that network measures are of practical value in high severity fault-proneness prediction. 展开更多
关键词 软件源代码 故障预测 网络化 实证分析 LOGISTIC回归分析 预测能力 严重程度 开源项目
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部