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Composition analysis of colored dissolved organic matter in Taihu Lake based on three dimension excitation-emission fuorescence matrix and PARAFAC model, and the potential application in water quality monitoring

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Journal of Environmental Sciences 2007年第7期19卷 787-791页

作者： WANG Zhi-gang liu wen-qing ZHAO Nan-jing LI Hong-bin ZHANG Yu-jun SI-MA Wei-cang liu Jian-guo School of Earth and Space Science University of Science and Technology of China Hefei 230026 China. Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 China

Taihu Lake is one of the five biggest lakes in China. Surface water samples from 26 sampling sites of Taihu Lake were collected. Furthermore wet chemical analysis （CODCr and BOD5） and measurement of three dimensional excitation-emission matrix （3DEEM） spectra in the laboratory have been conducted. Using parallel factor analysis （PARAFAC） model, three components of colored dissolved organic matter （CDOM） have been identified successfully, based on the analysis of 3DEEM data. The characteristics of the three components also have been described by comparing them to some components of CDOM, identified in earlier researches. Meanwhile, spatial variations of concentration for the three components in Taihu Lake have been analyzed, and the result indicates that the concentration of component 1 depends more on the situation of wastewater pollution and can be used as the indicator of wastewater pollution. The relationship between the concentrations of the three components and results of the wet chemical analysis show that none of the three components can be used as indicators of gross organic matter in water. However, the concentrations of all the three components have obvious linear relationships with the BOD5 value, especially for component 1 （r = 0.72878）. Finally, the potential applications of the composition analysis based on 3DEEM and PARAFAC model in water quality monitoring have been illuminated.

关键词： 3DEEM Taihu Lake monitoring of water quality CDOM PARAFAC

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杜牧的商於之行及其古道书写

商洛学院学报 2024年第1期38卷 6-13页

作者：刘文卿南开大学文学院天津南开300071

杜牧商於之行,除其存文自述的四次以外,另有至少三次。今见杜牧诗中,共十三首涉及商於之路。诗中地名,有“商山”“秦岭”“青泥阪”“蓝桥”“蓝溪桥”“丹水”“麻涧”“层峰驿”“武关”“青云馆”“富水驿”。杜牧的商於诗作,体现... 详细信息

杜牧商於之行,除其存文自述的四次以外,另有至少三次。今见杜牧诗中,共十三首涉及商於之路。诗中地名,有“商山”“秦岭”“青泥阪”“蓝桥”“蓝溪桥”“丹水”“麻涧”“层峰驿”“武关”“青云馆”“富水驿”。杜牧的商於诗作,体现其反思历史之理性,追慕忠正耿直之谏臣,抒发经世理想与桑梓情结,蕴含生计与亲情之双重压力,亦短暂流露出归隐志趣,表现出较丰富的文化意涵。

关键词：杜牧商於古道行迹诗作

Dyslipidemia and Outcome in Patients with Acute Ischemic Stroke

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Biomedical and Environmental Sciences 2014年第2期27卷 106-110页

作者： XU Tian ZHANG Jin Tao YANG Mei ZHANG Huan liu wen qing KONG Yan XU Tan ZHANG Yong Hong Department of Epidemiology School of Public Health Medical College of Soochow University Department of Neurology Chinese PLA 88 Hospital Department of Ophthalmology Affiliated Hospital of Nantong University

Objective To study the relationship between dyslipidemia and outcome in patients with acute ischemic stroke. Methods Data about 2 568 patients with acute ischemic stroke were collected from 4 hospitals in Shandong Province from January 2006 to December 2008. National Institute of Health Stroke Scale （NIHSS）〉10 at discharge or death was defined as the outcome. Effect of dyslipidemia on outcome in patients with acute ischemic stroke was analyzed by multivariate logistic regression analysis and propensity score-adjusted analysis, respectively. Results The serum levels of TC, LDL-C, and HDL-C were significantly associated with the outcome in patients with acute ischemic stroke. Multivariate logistic regression analysis and propensity score-adjusted analysis showed that the ORs and 95% CIs were 3.013 （1.259, 7.214）/2.655 （1.298, 5.43）, 3.157 （1.306, 7.631）/3.405 （1.621, 7.154）, and 0.482 （0.245, 0.946）/0.51 （0.282, O.921）, respectively, for patients with acute ischemic stroke. Hosmer-Lemeshow goodness-of-fit test showed no significant difference in observed and predicted risk in patients with acute ischemic stroke （chi-square=8.235, P=0.411）. Conclusion Serum levels of TC, LDL-C, and HDL-C are positively related with the outcome in patients with acute ischemic stroke.

关键词： Dyslipidemia Acute ischemic stroke Outcome Multivariate logistic regression analysis Propensity score-adjusted analysis

基于拟靶向代谢组学的3种基原大黄的差异成分研究

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中国中药杂志 2024年第9期49卷 2393-2401页

作者：赵江怡唐进程陈欣欣周易刘文清张媛刘凤波赵婷魏胜利北京中医药大学中药学院北京102488 中药材规范化生产教育部工程研究中心北京100102

大黄是典型的多基原大宗中药材,研究不同基原大黄药效成分含量和比例的差异,以期实现对不同基原大黄药材质量的精准评价,为大黄在临床上的精准用药提供理论依据。该研究以相同生长年限(四年生)的唐古特大黄、掌叶大黄和药用大黄为材料,... 详细信息

大黄是典型的多基原大宗中药材,研究不同基原大黄药效成分含量和比例的差异,以期实现对不同基原大黄药材质量的精准评价,为大黄在临床上的精准用药提供理论依据。该研究以相同生长年限(四年生)的唐古特大黄、掌叶大黄和药用大黄为材料,采用拟靶向代谢组学技术测定3种基原大黄中蒽醌、蒽酮及鞣质类共计220个成分的相对含量,并运用多元统计方法对差异成分进行筛选。主成分分析(PCA)结果显示,大黄样品按照基原明显聚为3类。通过正交偏最小二乘法判别分析(OPLS-DA),最终筛选出117种差异成分,其中包括:游离蒽醌类8种,结合蒽醌类18种,蒽酮类80种,鞣质类11种。综合比较,28种成分在唐古特大黄中含量较高,主要为番泻苷类、结合蒽醌类和原花青素类化合物;35种成分在药用大黄中含量较高,主要为游离蒽醌类和儿茶素类化合物;54种成分在掌叶大黄中含量较高,主要为二蒽酮类化合物,但其结构暂不能确定。通过对3种基原大黄差异成分的分析,根据差异成分在3种基原大黄中的含量分布情况可推测出:唐古特大黄的泻下攻积之力最强,药用大黄的清热泻火功效最强,且两者的逐瘀通经功效强于掌叶大黄。

关键词：大黄多基原拟靶向代谢组学差异成分精准中药

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大数据视阈下高校心理健康教育的机遇和挑战

湖北开放职业学院学报 2024年第2期37卷 155-157页

作者：林佳燕刘文庆无锡职业技术学院江苏无锡214121

大数据环境下,高校传统的心理健康教育面临的困境凸显,过度依赖心理测量,数据意识理念薄弱,心理教育人才短缺,主动服务难以彰显,制约着心理健康教育工作的成效。大数据时代,高校应当把握机遇,创新心理健康教育方式方法,提升心理健康教... 详细信息

大数据环境下,高校传统的心理健康教育面临的困境凸显,过度依赖心理测量,数据意识理念薄弱,心理教育人才短缺,主动服务难以彰显,制约着心理健康教育工作的成效。大数据时代,高校应当把握机遇,创新心理健康教育方式方法,提升心理健康教育研究科学性,构建心理健康数据整合平台,重塑心理健康教育人文关怀,并积极推动心理健康教育因材施教。通过觉醒大数据思维、培养心理工作大数据人才、健全大数据隐私保障机制,以提高高校心理健康教育的科学性和决策化水平。

关键词：大数据高校心理健康教育

Ni添加量对Al/Fe_(2)O_(3)能量释放特性的影响研究

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火工品 2024年第2期 46-51页

作者：庄治华刘宝振刘文庆董圣群石义刘兆虎贺川刘金旭北京理工大学材料学院北京100081 中国石油集团西部钻探工程有限公司新疆克拉玛依834000 北京环鼎科技有限责任公司北京102200 北京理工大学冲击环境材料技术国家级重点实验室北京100081

为探究Ni添加量对Al/Fe_(2)O_(3)能量释放特性的影响,采用球磨工艺制备了Ni质量分数为10%,20%,30%,40%的4种Al/Fe_(2)O_(3)/Ni高热剂,试验研究了Ni含量对高热剂反应热值、自蔓延燃烧性能、反应压力性能的影响,并对反应产物形貌和物相组... 详细信息

为探究Ni添加量对Al/Fe_(2)O_(3)能量释放特性的影响,采用球磨工艺制备了Ni质量分数为10%,20%,30%,40%的4种Al/Fe_(2)O_(3)/Ni高热剂,试验研究了Ni含量对高热剂反应热值、自蔓延燃烧性能、反应压力性能的影响,并对反应产物形貌和物相组成进行了分析。结果表明:随着Ni的质量分数由10%增加至40%,高热剂的反应热值从3.5 kJ·g^(-1)降至2.1 kJ·g^(-1),燃烧速率从0.35 m·s^(-1)降至0.04 m·s^(-1),反应压力峰值从0.16 MPa降至0.05 MPa。因此,通过调节Ni添加量,可以实现Al/Fe_(2)O_(3)/Ni高热剂燃烧特性在一定范围内的平稳调控。

关键词：高热剂反应热值燃烧特性反应压力镍

粒径对土壤石油烃荧光特性影响及校正方法研究

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光谱学与光谱分析 2024年第7期44卷 2093-2100页

作者：杨金强杨瑞芳赵南京殷高方方丽石高勇刘梁晨黄朋刘文清中国科学院合肥物质科学研究院安徽光学精密机械研究所安徽合肥230031 中国科学技术大学安徽合肥230026 安徽省环境光学监测技术重点实验室安徽合肥230031 合肥学院生物食品与环境学院安徽合肥230601

采用紫外诱导荧光技术对土壤中石油烃污染物进行检测时,不同粒径土壤会对测量带来较大误差,为了消除土壤粒径(soil particle size,PS)对测量带来的影响,配制3种不同粒径的常见的土壤石油烃污染物(土壤原油、土壤柴油、土壤汽油)样本,搭... 详细信息

采用紫外诱导荧光技术对土壤中石油烃污染物进行检测时,不同粒径土壤会对测量带来较大误差,为了消除土壤粒径(soil particle size,PS)对测量带来的影响,配制3种不同粒径的常见的土壤石油烃污染物(土壤原油、土壤柴油、土壤汽油)样本,搭建紫外诱导荧光检测系统,研究了不同粒径下各类土壤石油烃污染物的荧光特性,构建了土壤石油烃粒径校正方法。结果表明,对于土壤原油、土壤柴油和土壤汽油样本,当样本浓度为4、4和10 g·kg^(-1)时,各类型土壤油类样本的荧光信号与粒径具有良好的线性相关性,相关系数R^(2)分别达到了0.9989、0.9686和0.9045。通过土壤颗粒物吸附模型,对实验结果进行解释分析,建立土壤粒径校正方法,对各类型土壤石油烃样本在不同粒径下的荧光信号进行校正;粒径校正前后3种类型的土壤石油烃荧光强度与浓度的相关系数R^(2)分别由校正前的0.3265、0.0047、0.3298上升到校正后的0.9838、0.9832、0.9533,浓度反演的相对误差(RE)分别为11.02%、5.71%、10.19%。建立的土壤粒径校正方法可以有效地降低土壤粒径对土壤石油烃类污染物荧光强度的影响,为采用紫外诱导荧光技术快速、原位、准确的检测土壤石油烃类污染物提供了理论依据和技术支持。

关键词：土壤石油烃紫外诱导荧光土壤粒径校正方法

All types of base conversions allowed by base editors

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Science China(Life Sciences) 2024年第2期67卷 431-433页

作者： Shun-qing Liang wen Xue RNA Therapeutics Institute UMass Chan Medical SchoolWorcester 01655USA Department of Molecular Cell and Cancer BiologyUMass Chan Medical SchoolWorcester 01655USA Department of Molecular Medicine UMass Chan Medical SchoolWorcester 01655USA Li Weibo Institute for Rare Diseases Research UMass Chan Medical SchoolWorcester 01655USA

Base editors(BEs) hold great promise as tools for introducing single-base-pair changes in both basic research and therapeutic applications(Rees and liu,2018).Base editors are composed of a Cas9 nickase fused to a DNA-modifying enzyme,which chemically modifies nucleobases within a specific targeting window near the Cas9-binding site.

关键词： base bases allowed

Study of deep transportation and plugging performance of deformable gel particles in porous media

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Petroleum Science 2024年第2期21卷 962-973页

作者： wen-Jing Zhao Jing Wang Zhong-Yang Qi Hui-qing liu National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China

Deformable gel particles(DGPs) possess the capability of deep profile control and flooding. However, the deep migration behavior and plugging mechanism along their path remain unclear. Breakage, an inevitable phenomenon during particle migration, significantly impacts the deep plugging effect. Due to the complexity of the process, few studies have been conducted on this subject. In this paper, we conducted DGP flow experiments using a physical model of a multi-point sandpack under various injection rates and particle sizes. Particle size and concentration tests were performed at each measurement point to investigate the transportation behavior of particles in the deep part of the reservoir. The residual resistance coefficient and concentration changes along the porous media were combined to analyze the plugging performance of DGPs. Furthermore, the particle breakage along their path was revealed by analyzing the changes in particle size along the way. A mathematical model of breakage and concentration changes along the path was established. The results showed that the passage after breakage is a significant migration behavior of particles in porous media. The particles were reduced to less than half of their initial size at the front of the porous media. Breakage is an essential reason for the continuous decreases in particle concentration, size, and residual resistance coefficient. However, the particles can remain in porous media after breakage and play a significant role in deep plugging. Higher injection rates or larger particle sizes resulted in faster breakage along the injection direction, higher degrees of breakage, and faster decreases in residual resistance coefficient along the path. These conditions also led to a weaker deep plugging ability. Smaller particles were more evenly retained along the path, but more particles flowed out of the porous media, resulting in a poor deep plugging effect. The particle size is a function of particle size before injection, transport distance, and different injection

关键词： Physical simulation Deformable gel particle Breakage Particle size Residual resistance coefficient