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Variation of temporal and spatial patterns of NO_2 in Beijing using OMI and mobile DOAS

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Science China Chemistry 2015年第9期58卷 1367-1376页

作者： Ang Li Jie Zhang Pinhua Xie Zhaokun Hu Jin Xu Fusheng Mou Fengcheng Wu Jianguo liu wenqing liu Key Laboratory of Environmental Optical and Technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences School of Environmental and Photoelectric Technology University of Science and Technology of China

Control policies such as "odd-and-even license plate rule" were implemented by the Chinese government to restrict traffic and suspend factory production in Beijing and neighboring cities during the Asia-Pacific Economic Cooperation summit. We use ozone monitoring instrument(OMI), mobile differential optical absorption spectroscopy(DOAS), and multi-axis differential optical absorption spectroscopy(MAX-DOAS) to measure the variation of the spatial and temporal patterns of NO2 column densities from October 24, 2014 to November 22, 2014. It is found that the NO2 column densities during the episode of control policies are significantly lower than those during other periods, and the emission flux of NO2 calculated by mobile DOAS is also lower than the results from other periods. Some daily low NO2 column densities occur with the northwest wind direction. We then compare the relationship between OMI and mobile DOAS NO2 column density observations, and the results of mobile DOAS are approximately 2.7 times larger than the OMI values. The largest discrepancy occurs in the northern part of Beijing city. In other parts, the two instruments have a better correlation coefficient(R2) of 0.61. The low NO2 column densities that occur during the episode of control policies are affected by the control policies as well as meteorological conditions.

关键词： OMI DOAS NO2 emission flux control policies

中医药治疗急性淋巴细胞白血病的网络药理学及实验研究

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世界中医药 2024年第17期19卷 2562-2571页

作者：刘景文马秋玲苏雅静石慧慧郭家缘张曼刘洺欣李东东刘文卿河南中医药大学第二临床医学院郑州450046 河南省中医院郑州450002

目的:探究中医药治疗急性淋巴细胞白血病(ALL)的作用机制,并用实验验证。方法:收集中医药治疗ALL文献的药物组成;利用中药系统药理学数据库与分析平台(TCMSP)、通用蛋白质(UniProt)数据库收集高频中药的成分及靶点,基因表达综合系统(GEO... 详细信息

目的:探究中医药治疗急性淋巴细胞白血病(ALL)的作用机制,并用实验验证。方法:收集中医药治疗ALL文献的药物组成;利用中药系统药理学数据库与分析平台(TCMSP)、通用蛋白质(UniProt)数据库收集高频中药的成分及靶点,基因表达综合系统(GEO)数据库收集疾病靶点,取交集靶点,利用微生信平台进行基因本体(GO)富集分析和京都基因与基因组百科全书(KEGG)信号通路富集分析,利用Cytoscape 3.9.1构建蛋白质-蛋白质相互作用网络(PPI);基于网络药理学预测结果,用分子对接及实验进行验证。结果:筛选得到10个高频中药,包含157个有效成分及280个靶点,ALL相关的疾病靶点2428个,经筛选得到37个交集靶点,KEGG富集分析显示交集靶点作用于白细胞介素-17(IL-17)、化学致癌受体激活、T细胞受体等多种癌症、免疫和炎症反应相关的信号通路,核心有效成分为槲皮素,核心靶点为蛋白激酶B(AKT1),分子对接结果显示二者对接良好,细胞实验结果显示槲皮素处理后的ALL细胞活率明显降低,凋亡率明显升高(P<0.05),磷脂酰肌醇3-激酶(PI3K)、磷酸化蛋白激酶B(p-AKT)的表达均降低。结论:网络药理学的初步筛选与预测发现,中药可通过多成分、多靶点、多通路治疗ALL,其中的核心成分槲皮素可通过调控PI3K/AKT信号通路抑制ALL细胞增殖、诱导细胞凋亡,从而发挥抗ALL的作用,为中药治疗ALL有效成分的开发和运用提供参考。

关键词：急性淋巴细胞白血病中医药有效成分网络药理学细胞实验加权基因共表达网络分析分子对接作用机制

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Observation of the nighttime nitrate radical in Hefei, China

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Journal of Environmental Sciences 2008年第1期20卷 45-49页

作者： LI Suwen liu wenqing XIE Pinua LI Ang QIN Min PENG Fumin ZHU Yanwu Key Laboratory of Environmental Optical and Technology Anhui Institute of Optics and Fine MechanicsChinese Academy of Sciences Hefei 230031 China

Observation of nighttime nitrate radical （NO3） was performed by using long path differential optical absorption spectroscopy （LP- DOAS）, on the outskirts of Hefei, China. The time series of NO3 and supporting parameters were simultaneously measured for a week （31 May-7 June 2006）. The results indicated that the average concentration of NO3 was 15.6 pptv with an average lifetimes of 96 s, whereas, NO3 production rates varied from 8×10^2/（cm^3·s） to 2.98×10^7/（cm^3·s）. Furthermore, the calculated N2O5 concentration averaged at 380 pptv. Analysis of data indicated that direct sinks were probably dominating the NO3 loss process during this campaign. The results were compared with other campaigns in the boundary layer.

关键词： nitrate radical nighttime chemistry differential optical absorption spectroscopy sinks

Identification of long-range transport pathways and potential sources of PM2.5 and PM10 in Beijing from 2014 to 2015

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Journal of Environmental Sciences 2017年第6期29卷 214-229页

作者： Deping Li Jianguo liu Jiaoshi Zhang Huaqiao Gui Peng Du Tongzhu Yu Jie Wang Yihuai Lu wenqing liu Yin Cheng Key Laboratory of Environmental Optics and Technology AnhuiInstitute of Optics and Fine MechanicsChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Center for Excellence in Urban Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

Trajectory clustering, potential source contribution function （PSCF） and concentration-weighted trajectory （CWT） methods were applied to investigate the transport pathways and identify potential sources of PM2.s and PMIo in different seasons from June 2014 to May 2015 in Beijing. The cluster analyses showed that Beijing was affected by trajectories from the south and southeast in summer and autumn. In winter and spring, Beijing was not only affected by the trajectories from the south and southeast, but was also affected by trajectories from the north and northwest. In addition, the analyses of the pressure profile of backward trajectories showed that backward trajectories, which have important influence on Beijing, were mainly distributed above 970 hPa in summer and autumn and below 950 hPa in spring and winter. This indicates that PM2.s and PMIo were strongly affected by the near surface air masses in summer and autumn and by high altitude air masses in winter and spring. Results of PSCF and CV/T analyses showed that the largest potential source areas were identified in spring, followed by winter and autumn, then summer. In addition, potential source regions of PMIo were similar to those of PM2.5. There were a clear seasonal and spatial variation of the potential source areas of Beijing and the airflow in the horizontal and vertical directions. Therefore, more effective regional emission reduction measures in Beijing＇s surrounding provinces should be implemented to reduce emissions of regional sources in different seasons.

关键词： PM2.5 PM40 Cluster analyses PSCFCWT Beijing

A hydroxyl radical detection system using gas expansion and fast gating laser-induced fluorescence techniques

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Journal of Environmental Sciences 2018年第3期30卷 190-200页

作者： Hao Chen Renzhi Hu Pinhua Xie Xingbiao Xing liuyi Ling Zhiyan Li Fengyang Wang Yihui Wang Jianguo liu wenqing liu Department of Precision Machinery and Precision Instrumentation University of Science and Technology of China Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences CAS Center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Institute of Electric and Information Technology Anhui University of Science and Technology

An OH radical measurement instrument based on Fluorescence Assay by Gas Expansion（FAGE）has been developed in our *** air is introduced into a low-pressure fluorescence cell through a pinhole aperture and irradiated by a dye laser at a high repetition rate of 8.5 k *** OH radical is both excited and detected at 308 nm using A-X（0,0）*** satisfy the high efficiency needs of fluorescence collection and detection,a 4-lens optical system and a self-designed gated photomultiplier（PMT）is used,and gating is actualized by switching the voltage applied on the PMT dynodes.A micro channel photomultiplier（MCP）is also prepared for fluorescence *** the weak signal is accumulated by a photon counter in a specific *** OH radical excitation spectrum range in the wavelength of 307.82–308.2 nm is detected and the excited line for OH detection is determined to be Q1（2）*** calibration of the FAGE system is researched by using simultaneous photolysis of H2O and *** minimum detection limit of the instrument using gated PMT is determined to be 9.4×10~5molecules/cm^3,and the sensitivity is 9.5×10^（-7）cps/（OH·cm^（-3））,with a signal-to-noise ratio of 2 and an integration time of 60 sec,while OH detection limit and the detection sensitivity using MCP is calculated to be 1.6×10~5molecules/cm^3and 2.3×10^（-6）cps/（OH·cm^（-3））.The laboratory OH radical measurement is carried out and results show that the proposed system can be used for atmospheric OH radical measurement.

关键词： OH radical Laser-induced fluorescence Fluorescence assay by gas expansion Photomultiplier Photon counting

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傅里叶变换红外光谱自适应数字滤波算法研究

量子电子学报 2024年第2期41卷 226-234页

作者：孟伍德童晶晶高闽光李相贤李妍韩昕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中国科学院环境光学与技术重点实验室安徽合肥230031 中国科学技术大学安徽合肥230026

针对傅里叶变换红外(FTIR)光谱仪在不同类型环境噪声下导致的仪器性能下降的问题,提出了一种根据不同环境噪声实时更新滤波参数的自适应滤波算法。对该算法的基本原理和实现过程进行了理论推导,分析了不同滤波参数设置下的滤波效果,进... 详细信息

针对傅里叶变换红外(FTIR)光谱仪在不同类型环境噪声下导致的仪器性能下降的问题,提出了一种根据不同环境噪声实时更新滤波参数的自适应滤波算法。对该算法的基本原理和实现过程进行了理论推导,分析了不同滤波参数设置下的滤波效果,进而利用设计的滤波算法对实测光谱数据进行了滤波处理,对比分析了不同滤波方法下的光谱信噪比(SNR)。研究结果表明:基于巴特沃斯滤波的自适应FTIR光谱滤波方法在2100~2200 cm^(-1)和2500~2600 cm^(-1)波段的SNR较传统硬件滤波分别提高了1.29倍和1.13倍,表明该算法可以有效提升FTIR光谱信噪比,改善FTIR仪器的性能指标。

关键词：光谱学数字滤波巴特沃斯滤波器傅里叶变换红外光谱信噪比

肇庆市68308名新生儿葡萄糖-6-磷酸脱氢酶缺乏症筛查结果综合分析

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中国医学创新 2024年第15期21卷 166-170页

作者：胡雅刘文晴温宝欣李朝辉肇庆市第二人民医院(肇庆市妇幼保健院)检验科广东肇庆526060

目的:分析肇庆市68308名新生儿的葡萄糖-6-磷酸脱氢酶(G6PD)缺乏症筛查结果。方法:选取2021年1月—2022年12月在肇庆市出生的68308名新生儿为研究对象,采集全部新生儿的足跟血,以荧光分析法对G6PD缺乏症进行初筛,对可疑阳性者召回,采集... 详细信息

目的:分析肇庆市68308名新生儿的葡萄糖-6-磷酸脱氢酶(G6PD)缺乏症筛查结果。方法:选取2021年1月—2022年12月在肇庆市出生的68308名新生儿为研究对象,采集全部新生儿的足跟血,以荧光分析法对G6PD缺乏症进行初筛,对可疑阳性者召回,采集静脉血以连续监测法进行确诊。结果:2021年共筛查35610名,初筛阳性3580名,占比10.05%(3580/35610);2022年共筛查32698名,初筛阳性2983名,占比9.12%(2983/32698);6563例初筛阳性者,进行确诊检查,其中2021年确诊2585例,2022年确诊2153例,共确诊4738例G6PD缺乏症,确诊率为6.94%(4738/68308)。6563例初筛阳性者中,男5186例,女1377例;男婴初筛阳性中,共确诊3829例,确诊率为5.61%(3829/68308),女婴初筛阳性者中,共确诊909例,确诊率为1.33%(909/68308),男婴初筛阳性确诊率高于女婴初筛阳性确诊率,差异有统计学意义(χ^(2)=33.148,P<0.05);4738例G6PD缺乏症中,重度缺乏1130例,占比23.85%(1130/4738),中度缺乏1067例,占比22.52%(1067/4738),轻度缺乏2541例,占比53.63%(2541/4738)。结论:肇庆市68308名新生儿中,G6PD缺乏症以男婴为主,病情多为轻度缺乏。

关键词：葡萄糖 -6- 磷酸脱氢酶缺乏症新生儿筛查

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密实型沥青超薄罩面路用性能及应用效果研究

北方交通 2024年第7期 46-50页

作者：卢元均刘文庆邱彬吴寅李强安徽交控集团六安西中心外派交控工程集团六安市237000 南京林业大学土木工程学院南京市210000

为探究某断级配密实型超薄罩面路用性能及现场应用效果,选取两种常见的超薄罩面作为对照组进行试验研究。通过高温车辙试验、小梁弯曲试验及冻融劈裂试验,评价目标罩面与对照罩面的高温稳定性、低温抗裂性、水稳定性与抗滑性能。结合江... 详细信息

为探究某断级配密实型超薄罩面路用性能及现场应用效果,选取两种常见的超薄罩面作为对照组进行试验研究。通过高温车辙试验、小梁弯曲试验及冻融劈裂试验,评价目标罩面与对照罩面的高温稳定性、低温抗裂性、水稳定性与抗滑性能。结合江苏南部三段试验路工程,测定在交工时及运营10个月后目标罩面的道路平整度、压实度、抗滑性能和抗渗性能等指标变化。研究表明,目标罩面的高温稳定性最优异,较罩面B提升38%,较罩面C提升13%,同时低温弯曲破坏应变可达3000με左右;水稳定性与抗滑性能均表现优异,可满足实际路用需要。

关键词：超薄罩面路用性能检测指标应用效果

89份香蕉种质资源SRAP分子标记亲缘关系分析

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热带作物学报 2024年第4期45卷 703-711页

作者：周海琪夏玲吕顺曾莉莎王芳黄晓彦陈东仪刘文清梁少丽刘丽琴东莞市农业科学研究中心广东东莞523000

香蕉分类是一个难题,利用形态学特征进行分类已无法满足需要。分子标记技术逐渐被应用到香蕉品种(系)的种群鉴定与分类、亲缘关系分析和遗传多样性研究等方面。本研究采用SRAP分子标记技术对89份香蕉种质资源的亲缘关系进行分析。利用1... 详细信息

香蕉分类是一个难题,利用形态学特征进行分类已无法满足需要。分子标记技术逐渐被应用到香蕉品种(系)的种群鉴定与分类、亲缘关系分析和遗传多样性研究等方面。本研究采用SRAP分子标记技术对89份香蕉种质资源的亲缘关系进行分析。利用10对正反引物两两组合成100对引物组合,从中筛选出扩增条带易于识别、带型清晰、多态性高的13对SRAP引物,共扩增出170条可辨认条带,平均每对引物扩增13.08条,其中表现出多态性的条带有140条,多态性比率为79.00%。89份香蕉种质资源的相似系数的变化范围在0.241~1.000之间,遗传多样性非常丰富,来源于同一个地方或者来源不同地方的同一类型的野生蕉的相似性系数较高。当相似性系数为0.49时可以将这89份香蕉资源分成六大类,包括香牙蕉、贡蕉和龙牙蕉为主的第一大类(AAA、AA、AAB基因型),粉大蕉、粉蕉和BB类野蕉为主的第二大类(ABB、BB基因型),大蕉、阿宽蕉类野蕉为主的第三大类,以及红花蕉、地涌金莲、蝎尾蕉分别所属的第四、五、六类群。其结果与现行的经典分类结论基本一致,只有部分香蕉种质分类地位有差异,说明用SRAP标记对香蕉种质资源进行分类是可行的。同时,栽培类香牙蕉、贡蕉和龙牙蕉具有相同的祖先,与AA基因型野蕉亲缘关系近,粉蕉、粉大蕉与BB基因型的野蕉亲缘关系较近,不同基因组的香蕉种质资源聚到一起,说明香蕉种质资源的起源影响后代的亲缘关系,单一的分类方法无法将香蕉种质资源完全区分。此外,大蕉与阿宽蕉亲缘关系较近,但是无法分辨大蕉是否含有A和B基因组,因此大蕉基因型和遗传背景有待进一步研究。

关键词：香蕉 SRAP 聚类分析亲缘关系