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超高效液相色谱-串联质谱法测定环境水体中23种内分泌干扰物的含量

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理化检验（化学分册） 2024年第9期60卷 905-914页

作者：杨超尹明明王美飞刘景龙江苏省南京环境监测中心南京210013

提出了超高效液相色谱-串联质谱法(UHPLC-MS/MS)测定环境水体中23种内分泌干扰物(EDCs)含量的方法。用6 mol·L^(-1)盐酸溶液调节水样p H约为2.0,取100 mL水样置于250 mL分液漏斗中,加入3 g氯化钠,振荡,加入30 mL体积比1∶1的乙酸乙酯-... 详细信息

提出了超高效液相色谱-串联质谱法(UHPLC-MS/MS)测定环境水体中23种内分泌干扰物(EDCs)含量的方法。用6 mol·L^(-1)盐酸溶液调节水样p H约为2.0,取100 mL水样置于250 mL分液漏斗中,加入3 g氯化钠,振荡,加入30 mL体积比1∶1的乙酸乙酯-二氯甲烷混合溶液,振荡5 min,静置,下层有机相经无水硫酸钠除水,旋转蒸发近干后,加入乙腈0.2 mL,再加入2.0 mg·L^(-1)混合内标使用液10μL,用水定容至1 mL,过0.22μm再生纤维素滤膜后采用UHPLC-MS/MS测定滤液中23种EDCs的含量。以BEN C_(18)色谱柱为固定相,以不同体积比的0.05%(体积分数)氨水溶液-乙腈混合液为流动相进行梯度洗脱,质谱分析采用电喷雾离子(ESI)源,在负离子(ESI^(-))扫描模式下采用多反应监测(MRM)模式检测。结果表明,23种EDCs的质量浓度在一定范围内与对应的峰面积与内标峰面积比呈线性关系,检出限(3.143s)为0.60~1.75 ng·L^(-1);按照标准加入法进行回收试验,回收率为72.6%~107%,测定值的相对标准偏差(n=6)均小于14%;方法用于测定实际环境水体中23种EDCs的含量,结果显示在地表水中双酚AF的质量浓度最高,为27.9 ng·L^(-1),在污水及废水中普遍检出4-正壬基酚和4-特辛基酚,检出量分别为838~2 353 ng·L^(-1)和87.8~16 733 ng·L^(-1)。

关键词：超高效液相色谱-串联质谱法环境水体内分泌干扰物

Effects of Geometrical Characteristics of Suture on Fracture Resistance of Walnut Shell

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Journal of Bionic Engineering 2023年第6期20卷 2732-2741页

作者： Peng Xu Lizhen Wang jinglong liu Yanxian Yue Yubo Fan Key Laboratory of Biomechanics and Mechanobiology(Beihang University) Ministry of EducationBeijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijing100083China School of Engineering Medicine Beihang UniversityBeijing100083China

Nut shells have good impact and fracture resistance,but many kinds of nut shells have suture structures with low bonding ***,the mechanism of impact and fracture resistance of nut shells as a whole is important to study,particularly given that sutures maintain low bonding *** this study,we investigated the effect of the geometrical characteristics of sutures(morphology,thickness,and number)on the overall fracture resistance of walnuts,based on mechanical tests of C-ring samples,microstructure analysis after cracking,quantitative analysis of suture geometric model,and numerical *** found that the cracking of walnuts was mainly caused by tensile stress,and the bonding strength was approximately 2.48±0.64 *** discovered that the thickness of the suture was 1.55±0.32 times thicker than the shell,which improved the fracture resistance ability by more than 28.4%.The undulating and inclined morphology of the walnut suture also increased the fracture ***,an appropriate suture number reduced the cracking of *** conclusion,our study sheds light on the physiological function of walnut sutures from a biomechanical perspective and provides useful references for designing fracture resistance measures in thin shell structures.

关键词： Fracture resistance Walnut Suture Bonding strength Numerical simulations Biomechanics

浊点萃取-气相色谱-质谱法测定水中9种芳香胺类化合物

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色谱 2024年第3期42卷 296-303页

作者：杨超刘景龙徐孝健吴丽娟尹明明戴维韩倩江苏省南京环境监测中心江苏南京210013 江苏省扬州环境监测中心江苏扬州225007

本研究基于以曲拉通X-114(Triton X-114)为萃取剂的浊点萃取技术和气相色谱-质谱法,建立了一种高效、高灵敏度的水体中9种芳香胺(2-氯胺、3-氯胺、4-氯胺、2-硝基苯胺、3-硝基苯胺、4-硝基苯胺、1-萘胺、2-萘胺和4-氨基联苯)的检测方法... 详细信息

本研究基于以曲拉通X-114(Triton X-114)为萃取剂的浊点萃取技术和气相色谱-质谱法,建立了一种高效、高灵敏度的水体中9种芳香胺(2-氯胺、3-氯胺、4-氯胺、2-硝基苯胺、3-硝基苯胺、4-硝基苯胺、1-萘胺、2-萘胺和4-氨基联苯)的检测方法。采用单因素优化法对影响提取效果的重要因素进行了优化。采用气相色谱-质谱对水中9种芳香胺进行定性、定量分析,使用中等极性色谱柱DB-35 MS(30 m×0.25 mm×0.25μm)进行分离,在选择离子模式(SIM)下测定,内标法定量。实验结果表明,9种芳香胺在16 min内能够完全分离,且在各自的范围内线性关系良好,相关系数(R^(2))均大于0.998。9种芳香胺的检出限(LOD)和定量限(LOQ)分别为0.12~0.48μg/L和0.40~1.60μg/L。选取饮用水源地地表水、近海海水和典型印染行业废水3种类型水体进行加标回收试验,在2个加标水平(2.0、10.0μg/L)下,饮用水源地地表水的加标回收率为81.1%~109.8%,日内精密度为0.7%~5.2%,日间精密度为1.6%~6.2%;近海海水的加标回收率为83.0%~115.8%,日内精密度为1.5%~8.6%,日间精密度为2.4%~12.2%;典型印染行业废水的加标回收率为91.0%~120.0%,日内精密度为2.9%~12.9%,日间精密度为2.5%~13.1%。采用所建立方法对饮用水源地地表水、近海海水和典型印染行业废水中的9种芳香胺进行检测,在饮用水源地地表水和近海海水中均未检出目标组分,而在印染行业废水中主要检出2-氯胺、4-氯胺和4-氨基联苯3种印染行业常用的芳香胺。与其他方法相比,该方法具有操作简单、灵敏度高、成本低、有机试剂用量少、重复性较好等优点,为水中芳香胺及其他痕量有机物的测定提供了技术支持。

关键词：浊点萃取气相色谱-质谱法芳香胺环境水样

Biological analysis of woodpecker’s brain after impact experiments

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Science China(Technological Sciences) 2021年第5期64卷 1101-1106页

作者： XU Peng NI YiKun liu jinglong ZHANG WeiRong liu SiJian WANG LiZhen FAN YuBo Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education Beijing Advanced Innovation Centre for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijing 100083China

Woodpeckers can withstand a fierce impact during *** studies have focused on the biomechanical analysis of the pecking process,the properties of the beak and hyoid bone of woodpecker;however,the biological characteristics of the woodpecker brain are also important in resisting impact *** employed impact experiments and biological analysis in normal and injured brains to reveal the impact-resistant biological characteristics of woodpecker brains,as well as the impact energy’s biological effects on the woodpecker *** hoopoe,which has a similar size but only a slight pecking behavior,was selected as the control group to compare brain morphology and neuronal cells differences in normal brains between woodpecker and hoopoe by sectioning and staining.A loading device was designed to conduct a quantifiable impact energy to the woodpeckers’*** groups of woodpeckers were impacted with the same energy on the forehead,beak,tempus and occiput,*** changes in the injured brains were evaluated by Nissl staining and enzyme-linked immunosorbent *** results showed that:(1)woodpeckers had a larger cerebellum and a higher density of Nissl bodies than hoopoe;(2)Nissl apoptosis appeared in the brain samples after the forehead and the occiput impact experiments,but no obvious Nissl body apoptosis was observed after impact on the tempus and the beak;(3)β-amyloid protein accumulated in the normal status woodpecker *** study reveals that:woodpecker brain morphology is well-adapted to impact,woodpecker heads display location-dependent protective performance,with beak and tempus regions having a better protective performance than the forehead and occiput,Nissl apoptosis appears in injured woodpecker brains,and that the accumulation ofβ-amyloid protein does not show a direct relationship with the injury state of woodpecker’s brain tissue in our study.

关键词： woodpecker biomechanics impact experiments impact resistance biological analysis

Integration of satellite remote sensing data in underground coal fire detection:A case study of the Fukang region,Xinjiang,China

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Frontiers of Earth Science 2020年第1期14卷 1-12页

作者： Shiyong YAN Ke SHI Yi LI jinglong liu Hongfeng ZHAO Ministy of Natural Resource Key Lab of Land Environment and Disaster Monitoring China University of Mining and TechnologyXuzhou 221116China School of Environment Science and Spatial Informatics China University of Mining and TechnologyXuzhou 221116China Comprehensive Geological Exploration Team in Coal Geology Bureau of Xinjiang Uygur Autonomous Region Urumchi 830009China

Xinjiang in China is one of the areas worst affected by coal *** fires cannot only waste a large amount of natural resources and cause serious economic losses,but they also cause huge damage to the atmosphere,the soil,the surrounding geology,and the ***,there is an urgent need to effectively explore remote sensing based detection of coal fires for timely understanding of their latest development *** this study,in order to investigate the distribution of coal fires in an accurate and reliable manner,we exploited both Landsat-8 optical data and Sentinel-1A synthetic aperture radar(SAR)images,using the generalized single-channel algorithm and the InSAR time-series analysis approach,respectively,for coal fire detection in the southern part of the Fukang region of Xinjiang,*** generalized single-channel algorithm was used for land surface temperature information ***,the timeseries InSAR analysis technology was employed for estimating the surface micro deformation information,which was then used for building a band-pass *** suspected coal fire locations could then be established by a band-pass filtering operation on the obtained surface temperature ***,the locations of the suspected coal fires were validated by the use of field survey *** results indicate that the integration of thermal infrared remote sensing and radar interferometry technologies is an efficient investigation approach for coal fire detection in a large-scale region,which would provide the necessary spatial information support for the survey and control of coal fires.

关键词： land surface temperature generalized singlechannel algorithm surface deformation time-series InSAR analysis filtering operation coal fire detection

“以需定供”:2024—2050年托育需求与供给规模预测——以上海市为例

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人口与发展 2024年第4期30卷 104-118页

作者：王雅楠高传胜刘竞龙 [印度]阿什温·库马尔·古拉詹南京中医药大学卫生经济管理学院江苏南京210023 南京大学政府管理学院江苏南京210023 加泰罗尼亚理工大学信号理论与通讯学院西班牙巴塞罗那08034 加泰罗尼亚理工大学超级计算机中心西班牙巴塞罗那08034

少子化形势客观上要求以需求为导向推动托育服务供给。基于Bootstrapping改进的ARIMA-LSTM模型测算2024—2050年上海市人口规模与出生率,进而考察在动态变化的入托率下幼儿园、托育机构的托育需求与供给规模。结果显示:托位缺口大,且供... 详细信息

少子化形势客观上要求以需求为导向推动托育服务供给。基于Bootstrapping改进的ARIMA-LSTM模型测算2024—2050年上海市人口规模与出生率,进而考察在动态变化的入托率下幼儿园、托育机构的托育需求与供给规模。结果显示:托位缺口大,且供需缺口经历了“起步-快速增长-稳定回落”过程。起步期(2024—2032年)幼儿园、托育机构的平均供需缺口分别为0.62万、3.58万个,应供给310个幼儿园托班与298所托育机构。快速增长期(2033—2042年)幼儿园、机构的供需缺口为2.42万、10.24万个。在第一阶段的基础上,还需供给900个托班与619所机构。稳定回落期(2043—2050年)幼儿园、机构的供需缺口回落至2.36万、10.94万个。若第二阶段已经补足缺口,则无需再增加供给。学前教育学位的持续释放为幼儿园下设托班提供了基础,但是其师资与财政经费的短缺,以及托育机构规模增长的压力是制约托育服务有效供给的关键。

关键词：人口预测托育需求托育服务供给托育机构学前教育

Establishment of a selective evaluation method for DPP4 inhibitors based on recombinant human DPP8 and DPP9 proteins

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Acta Pharmaceutica Sinica B 2014年第2期4卷 135-140页

作者： jinglong liu Yi Huan Caina Li Minzhi liu Zhufang Shen State Key Laboratory of Bioactive Substances and Functions of Natural Medicines Diabetes Research CenterInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Dipeptidyl peptidase 4(DPP4)is recognised as an attractive anti-diabetic drug target,and several DPP4 inhibitors are already on the *** members of the same gene family,dipeptidyl peptidase 8(DPP8)and dipeptidyl peptidase 9(DPP9)share high sequence and structural homology as well as functional activity with ***,the inhibition of their activities was reported to cause severe ***,the development of DPP4 inhibitors that do not have DPP8 and DPP9 inhibitory activity is critical for safe anti-diabetic *** achieve this goal,we established a selective evaluation method for DPP4 inhibitors based on recombinant human DPP8 and DPP9 proteins expressed by Rosetta *** this method,we used purified recombinant 120 kDa DPP8 or DPP9 protein from the Rosetta expression *** optimum concentrations of the recombinant DPP8 and DPP9 proteins were 30 ng/mL and 20 ng/mL,respectively,and the corresponding concentrations of their substrates were both 0.2 mmol/*** method was highly reproducible and reliable for the evaluation of the DPP8 and DPP9 selectivity for DPP4 inhibitor candidates,which would provide valuable guidance in the development of safe DPP4 inhibitors.

关键词： DPP4 DPP8 DPP9 Inhibitor Selective evaluation method

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电力科研企业危化品全生命周期安全管理研究

电力安全技术 2024年第2期26卷 5-8页

作者：刘景龙赵鹏冯国杰佟新元陈玉峰国网山东省电力公司电力科学研究院山东济南250003 国网山东省电力公司山东济南250001

针对电力科研企业危化品安全风险管控中的突出问题,从健全规章制度、构建双预机制、深化教育培训、推进智慧管控、夯实应急处置五个方面,构建基于全生命周期的危化品安全管理体系,提升危化品安全管控水平,推进危化品安全管理数字化转型... 详细信息

针对电力科研企业危化品安全风险管控中的突出问题,从健全规章制度、构建双预机制、深化教育培训、推进智慧管控、夯实应急处置五个方面,构建基于全生命周期的危化品安全管理体系,提升危化品安全管控水平,推进危化品安全管理数字化转型与智能化升级。

关键词：电力科研企业危化品全生命周期安全管理

Analysis of the Correlation among Three Oxygen Demand Indexes in Surface Water

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Meteorological and Environmental Research 2022年第2期13卷 61-64页

作者： Bin YANG Jing liu jinglong liu Tongling Environmental Monitoring Central Station Tongling 244000China Jiangsu Nanjing Environmental Monitoring Center Nanjing 210013China

Based on the monitoring data of chemical oxygen demand(COD),permanganate index(I Mn)and five-day biochemical oxygen demand(BOD 5)of surface water in Tongling section of Yangtze River,the linear relationship among the three indexes in the annual data analysis and the internal reasons,as well as the linear relationship and changes among the three indexes in different seasons were *** results reveal that in terms of the whole year,COD,I Mn and BOD 5 had a significant correlation and good linear *** fitting slopes of the three indexes were 3.89 of COD/I Mn,4.39 of COD/BOD 5 and 1.16 of I Mn/BOD 5,respectively,which corresponded to the proportional relationship among the three *** the perspective of seasonal changes,there was a very significant correlation between the three indexes in spring and *** autumn and winter,only COD and I Mn had a good correlation,but they had a poor correlation with BOD 5.

关键词： Chemical oxygen demand Permanganate index Biochemical oxygen demand Season Correlation