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淋洗法处理铬污染土壤研究进展

绿色矿冶 2024年第2期40卷 66-72页

作者：郭伯厚陈睿颉张基尧凌晓杰王娟嘉兴大学生物与化学工程学院浙江嘉兴314033

重金属铬进入土壤后不仅会污染地下水,还会在植物体内累积进而危害人体健康。淋洗技术具有操作简单、节约成本、效果显著等优点,是较为常用的铬污染土壤处理方法。本文整理和归纳了目前有关铬污染土壤淋洗的研究,介绍各种淋洗剂的淋洗... 详细信息

重金属铬进入土壤后不仅会污染地下水,还会在植物体内累积进而危害人体健康。淋洗技术具有操作简单、节约成本、效果显著等优点,是较为常用的铬污染土壤处理方法。本文整理和归纳了目前有关铬污染土壤淋洗的研究,介绍各种淋洗剂的淋洗原理、应用及存在问题,分析影响淋洗效果的因素,如土壤性质、淋洗剂性质、淋洗液pH值、淋洗时间、液固比及增强方式等,并针对铬污染土壤淋洗存在的黏性土壤中铬淋洗效率不高、淋洗后土壤的生态风险评价不足、淋洗废水处理和资源化不足等问题,提出相应建议。

关键词：铬污染土壤淋洗淋洗剂种类影响因素

Lidar observation campaigns on diurnal variations of the sodium layer in Beijing and Wuhan, China

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Science China Earth Sciences 2015年第8期58卷 1377-1386页

作者： GONG ShaoHua YANG GuoTao CHENG XueWu GONG Shun sheng XU jiyao LI FaQuan GONG Wei WANG JiHong School of Physics and Electronics Engineering Hainan Normal University State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences Laboratory of Optoelectronics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University

Based on observations from daytime lidars in eastern China,diurnal cycles of the sodium layer over Wuhan(30.5°N,114.6°E)and Beijing(40.5°N,116°E)are *** variations of Na density,root mean square(RMS)layer width,and centroid height of the sodium layer are *** reveal that the large diurnal cycles of the sodium layer are controlled mainly by 24-hr oscillations at the two observation *** diurnal variation of the sodium layer over Wuhan was modulated mainly by tidal perturbations during the lidar observation ***,the diurnal variation over Beijing was controlled principally by photoionization and photochemistry effects during another campaign,and there was little evidence of direct tidal *** comparisons suggest that the diurnal variation of the sodium layer perhaps has obvious regional characteristics across *** variation can be either controlled mainly by tidal perturbations or by photoionization and photochemistry effects in different seasons.

关键词：激光雷达观测日变化钠层武汉北京光化学效应运动控制中国东部

Nighttime anomaly of ionospheric electron density

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Science China Earth Sciences 2016年第7期59卷 1517-1518页

作者： XU jiyao LIU Xiao State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences School of Mathematics and Information Science Henan Normal University

The ionosphere is composed of a large number of electrons and ions, which are produced by the photoionization effect of the solar radiation on the neutral atmosphere. The altitude range of ionosphere is about 60–1000 km and varies with local time and other factors (e.g., solar and geomagnetic activity). Although the ionosphere varies over multiply timescales, the diurnal variation is in the dominant position due to the sun’s photoionization effect. Consequently, it is expected that the ionospheric electron density increases

关键词：电子密度电离层多时间尺度异常太阳辐射电离作用地磁活动电离效应

Contribution of the Chinese Meridian Project to space environment research:Highlights and perspectives

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Science China Earth Sciences 2023年第7期66卷 1423-1438页

作者： Chi WANG jiyao XU Libo LIU Xianghui XUE Qinghe ZHANG Yongqiang HAO Gang CHEN Hui LI Guozhu LI Bingxian LUO Yajun ZHU Jiangyan WANG State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China School of Earth and Space Sciences University Science and Technology of ChinaHefei 230026China Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China School of Earth and Space Sciences Peking UniversityBeijing 100191China Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China Key Laboratory of Science and Technology on Environmental Space Situation Awareness National Space Science CenterChinese Academy of SciencesBeijing 100190China

The Chinese Meridian Project(CMP)is devoted to establishing a comprehensive ground-based monitoring network for China’s space weather *** is a major national science and technology infrastructure project with the participation of more than 10 research institutions and universities led by the National Space Science Center of the Chinese Academy of *** is planned to be constructed in two phases:CMP phasesⅠandⅡ.The first phase(CMP-Ⅰ)started construction in2008 and completed in 2012,after which it entered the operation *** 10-year observation of CMP-Ⅰhas made significant scientific discoveries and achievements in the research fields of the middle and upper atmospheric fluctuations,metal layers in the mesosphere and lower thermosphere,ionospheric disturbances and irregularities,geomagnetic disturbances,and influences of solar *** review summarizes the main observations and research achievements,space weather forecast modeling and methods based on CMP-Ⅰover the past 10 years,and presents a future extension perspective along with the construction of CMP-Ⅱ.

关键词： Chinese Meridian Project Ground-based observation network Space weather Solar-terrestrial physics

Identification and expression analysis of chlorogenic acid biosynthesis key gene PpHCT in peach

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Horticultural Plant Journal 2023年第4期9卷 670-680页

作者： Ziwen Su Meng Sun Zhixiang Cai Shaolei Guo jiyao Li Bintao Zhao Zhijun Shen Ruijuan Ma Juan Yan Mingliang Yu College of Horticulture Nanjing Agricultural UniversityNanjingJiangsu 210095China Institute of Pomology Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic ImprovementNanjingJiangsu 210014China

Shikimic acid/quinic acid hydroxy cinnamyl transferase(HCT)is one of the key enzymes in the phenylpropanoid ***,the role of the HCT gene in chlorogenic acid(CGA)biosynthesis in peach fruit remains *** this,we identified the accumulation pattern of CGA in four peach cultivars,cloned and characterized 11 PpHCT gene members,and further analyzed the expression patterns of these PpHCT genes during fruit *** contents of CGAs in the four peach cultivars all exhibited a trend of increasing and then decreasing during the fruit growth and ***,the contents of CGAs in the peel and flesh were *** structure analysis indicated that the PpHCT genes were highly conserved,containing two exons and one *** protein structure analysis demonstrated that the PpHCT proteins contained two conserved motifs(HXXXD,DFGWG)and a transferase domain(PF02458),which belonged to the BAHD acyltransferase *** cis-acting element analysis suggested that the promoters of PpHCT genes contained many light-related,hormone-related,stress-related,tissue-specific,and circadian-related elements,and they could participate in a variety of biological *** analysis showed that the HCT proteins of peach were closely related to the HCT proteins of plum and had a close evolutionary *** qRT-PCR analysis indicated that the expression levels of PpHCT1 and PpHCT2 showed an opposite trend to the accumulation of CGA,whereas the expression levels of PpHCT4,PpHCT5,PpHCT7,PpHCT8,and PpHCT11 demonstrated the same trend as CGA *** was worth noting that only PpHCT4 and PpHCT5 were highly expressed in the two high-CGA cultivars but showed low levels of expression in the two low-CGA ***,it was hypothesized that these two genes might be key genes to the synthesis of CGA in peach *** findings provide a theoretical basis for further study on the biological functions of the HCT gene and help to

关键词： Prunus persica(L.) Chlorogenic acid PpHCT Bioinformatics analysis Gene expression

基于期刊文献数据库的冠心病心律失常中医用药规律研究

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临床合理用药杂志 2024年第19期17卷 1-5,9页

作者：兰昌林康善平赵继尧刘鑫李鑫蒙定水广西中医药大学南宁市530001 广西中医药大学附属瑞康医院南宁市530011

目的运用数据挖掘方法分析中医治疗冠心病心律失常的临床用药规律。方法收集维普网数据库、万方数据知识服务平台和中国知网(CNKI)等数据库中以冠心病心律失常为主题词收集相关的文献,检索时限自建库至2023年1月,并筛选出中药处方数据... 详细信息

目的运用数据挖掘方法分析中医治疗冠心病心律失常的临床用药规律。方法收集维普网数据库、万方数据知识服务平台和中国知网(CNKI)等数据库中以冠心病心律失常为主题词收集相关的文献,检索时限自建库至2023年1月,并筛选出中药处方数据,利用Excel 2019归纳整理原始方药数据,核对各味中药的性、味、归经信息并分别进行频数统计。应用SPSS Modeler 18.3软件基于Apriori算法进行关联规则分析,应用IBM SPSS Statistics 25.0对处方数据进行聚类分析和因子分析。结果共收录符合标准的文献99篇,从中录入中药处方99组,包含133味中药,中药累积使用频次1 091次。其中甘草、丹参、桂枝等高频中药(频次≥20)共16味,性味以温、寒、甘、苦居多,归经主要以脾经、肝经、肺经为主,二阶关联规则分析中以甘草—桂枝支持度最高;三阶关联药物中以甘草—麦冬—丹参的组合支持度最高。因子分析降维得出5个公因子,功效主要有滋阴养血、益气活血等。结论冠心病心律失常用药性味以苦寒为主,多从脾、肝、肺三经出发,功效相对集中,以滋阴养血、益气通脉为主。

关键词：冠心病心律失常数据挖掘用药规律

Cause of winter gravity wave spectrum saturation

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Science China Earth Sciences 2005年第10期48卷 1802-1808页

作者： WU Yongfu XU jiyao Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 China Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 China

This paper utilizes horizontal velocity measurements observed from 19 chaff rockets and nearly simultaneous temperature measurements collected from 19 falling sphere rockets to study the cause of winter gravity wave spectrum saturation. Results suggest that strong hori-zontal velocity shears larger than 0.04 s?1 are observed to be present at various heights near the winter mesopause. On one single chaff rocket flight, an extremely strong horizontal velocity shear as high as 0.33 s?1 is observed at 87.4 km and is believed to be the strongest value ever meas-ured in the mesosphere. These strong horizontal velocity shears, together with Brunt-V?is?l? frequency squared obtained from the temperature profile, act collectively to yield two dynamical instability regions of Richardson number smaller than 1/4, suggesting that the saturated gravity wave spectrum observed by the chaff rockets in winter is a result of dynamical instability.

关键词： winter spectrum, strong shear, dynamical instability, spectrum saturation.

Daytime lidar measurements of the sodium layer in China

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Science China Earth Sciences 2016年第8期59卷 1707-1708页

作者： LIU Xiao XU jiyao School of Mathematics and Information Science Henan Normal University State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences

Metal layers are formed owing to the deposition of metal species, such as, Na, Fe, Ma, Si, Ca, and K, in the mesosphere and lower thermosphere region. The metal species come from the meteor ablations when meteors enter into the atmosphere (Plane, 1991). Among these species, Na can be easily detected by sodium lidar since it has enough abundance and large backward scattering cross-section. On the other hand, the chemical lifetime of the sodium layer is longer

关键词： lidar backward lifetime enough abundance longer

Recent investigation on the coupling between the ionosphere and upper atmosphere

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Science China Earth Sciences 2014年第9期57卷 1995-2012页

作者： WAN WeiXing XU jiyao Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences State Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences

Scientific attention has recently been focused on the coupling of the earth's upper atmosphere and ionosphere. In the present work, we review the advances in this field, emphasizing the studies and contributions of Chinese scholars. This work first introduces new developments in the observation instruments of the upper atmosphere. Two kinds of instruments are involved: optical instruments(lidars, FP interferometers and all-sky airglow imagers) and radio instruments(MST radars and all-sky meteor radars). Based on the data from these instruments and satellites, the researches on climatology and wave disturbances in the upper atmosphere are then introduced. The studies on both the sporadic sodium layer and sporadic E-layer are presented as the main works concerning the coupling of the upper atmosphere and the low ionosphere. We then review the investigations on the ionospheric longitudinal structure and the causative atmospheric non-migrating tide as the main progress of the coupling between the atmosphere and the ionospheric F2-region. Regarding the ionosphere-thermosphere coupling, we introduce studies on the equatorial thermospheric anomaly, as well as the influence of the thermospheric winds and gravity waves to the ionospheric F2-region. Chinese scholars have made much advancement on the coupling of the ionosphere and upper atmosphere, including the observation instruments, data precession, and modeling, as well as the mechanism analysis.

关键词：低电离层高层大气耦合观测仪器中国学者激光雷达热层风光学仪器