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气—质联用法同时检测高脂食品中14种光引发剂

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食品与机械 2018年第8期34卷 54-59页

作者：徐文泱陈华湖南省食品质量监督检验研究院湖南长沙410017

建立气相色谱-质谱联用仪测定高脂食品中14种光引发剂的方法。将均质后的试样经丙酮-正己烷(体积比2:8) 20℃提取15 min后,振荡离心,上清液采用HLB管进行净化,收集洗脱液,并以PSA萃取管进一步净化。离心后提取上机。当加标水平为0. 000 ... 详细信息

建立气相色谱-质谱联用仪测定高脂食品中14种光引发剂的方法。将均质后的试样经丙酮-正己烷(体积比2:8) 20℃提取15 min后,振荡离心,上清液采用HLB管进行净化,收集洗脱液,并以PSA萃取管进一步净化。离心后提取上机。当加标水平为0. 000 2~0. 001 0 mg/kg时的回收率为73. 0%~92. 4%,相对标准偏差为4. 1%~8. 9%,检出限为0. 02~0. 20μg/kg。该方法操作快捷,技术参数均满足GB/T 27404—2008附录F中的要求,适用于高脂食品中14种光引发剂的同时分析。

关键词：气相色谱-质谱联用法光引发剂高脂食品检测

Specifically targeting human telomeric dimeric G-quadruplexes by polyehter-tethered di-berberine derivatives

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Specifically targeting human telomeric dimeric G-quadruplexe...

Wave effect of gravitational waves intersected with a microlens field Ⅱ:An adaptive hierarchical tree algorithm and population study

中国化学会第四届卟啉与酞菁学术研讨会

作者： Zi-Qi Li Ting-Cong Liao wen-hua chen Chun-Qiong Zhou Guangdong Provincial Key Laboratory of New Drug Screening School of Pharmaceutical SciencesSouthern Medical University

The design and synthesis of binders specifically multiple G-quadruplex units in the 3’-terminal overhang of human telomeric DNA has attracted considerable attention,which will promote to develop some selective anticancer agents with fewer side *** three polyether-tethered di-berberine compounds（1-3） have been prepared and studied on their binding affinity,selectivity and thermal stabilization towards dimeric quadruplex DNA by UV-Vis titrations,electrophoresis,fluorescence spectroscopy,CD spectroscopy and *** 1 with the shortest polyether linker has been found to have higher binding affinity,selectivity and thermal stabilization towards mixed-type dimeric quadruplexes over antiparallel dimeric and monomeric quadruplexes than compounds 2-3 with the longer polyether *** intriguingly,four molecules of compound 1 might externally stack on the end G-quartets of the two mixed-type G-quadruplex units on one dimeric *** addition,these diberberine derivatives displayed good inhibitory activities toward four tumor cell lines.

关键词： Di-berberine dimeric quadruplex DNA telomere binding selectivity

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 241-254页

作者： Xikai Shan Guoliang Li Xuechun chen wen Zhao Bin Hu Shude Mao Department of Astronomy Tsinghua University Purple Mountain Observatory Chinese Academy of Sciences Institute for Frontier in Astronomy and Astrophysics Beijing Normal University School of Physics and Astronomy Beijing Normal University School of Astronomy and Space Science University of Science and Technology of China CAS Key Laboratory for Researches in Galaxies and Cosmology Department of Astronomy University of Science and Technology of ChinaChinese Academy of Sciences

The gravitational lensing wave effect generated by a microlensing field embedded in a lens galaxy is an inevitable phenomenon in strong lensed gravitational waves （SLGWs）.This effect presents both challenges and opportunities for the detection and application of ***,investigating this wave effect requires computing a complete diffraction integral over each microlens in the *** is extremely time-consuming due to the large number of microlenses （10～3-10～6）.Therefore,simply adding all the microlenses is ***,the complexity of the time delay surface makes the lens plane resolution a crucial factor in controlling numerical *** this paper,we propose a trapezoid approximation-based adaptive hierarchical tree algorithm to meet the challenges of calculation speed and *** find that this algorithm accelerates the calculation by four orders of magnitude compared to the simple adding method and is one order of magnitude faster than the fixed hierarchical tree algorithm proposed for electromagnetic *** importantly,our algorithm ensures controllable numerical errors,increasing confidence in the *** with our previous work （***.66,239511,2023）,this paper addresses all numerical issues,including integral convergence,precision,and computational time1).Finally,we conducted a population study on the microlensing wave effect of SLGWs using this algorithm and found that the microlensing wave effect cannot be ignored,especially for Type II SLGWs （from saddle position of the time delay surface） due to their intrinsic geometric structures and their typical intersection with a denser microlensing ***,more than 33%（11%） of SLGWs have a mismatch larger than 1%（3%） compared to the unlensed ***,we found that the mismatch between signal pairs in a doubly imaged GW is generally larger than 10-3,and 61%（25%） of signal pairs have a mismatch larger than 1%（3%）.Therefo

关键词： gravitational lensing diffractional integral algorithm gravitational wave

Spiral CT localization of pancreatic function-ing islet cell tumors

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Hepatobiliary & Pancreatic Diseases International 2004年第4期3卷 616-619页

作者： Qing Xu, wen-hua chen and Qing-Juan huang Nanjing, China Department of Radiology, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China Department of Radiology, Third Affiliated Hospital of Suzhou Univer- sity, Changzhou 213003, China Department of Radiology First Affiliated Hospital of Nanjing Medical University Nanjing 210029 China. xuqingst@***

BACKGROUND: Surgeons are always concerned about the localization of pancreatic functioning islet cell tumor. If the tumor is accurately localized before operation, resection of the pancreatic body and tail without intention can be avoided. The purpose of this study was to evaluate spiral CT localization of pancreatic functioning islet cell tumors and CT techniques. METHODS: CT manifestations in 6 patients with clinically and pathologically proved pancreatic functioning islet cell tumors ware analyzed retrospectively. RESULTS: In 4 patients with insulinomas and 2 patients with glucagonomas, 5 were localized accurately by CT be- fore surgery and 1 was detected retrospectively. The en- hancement of tumors was greater than that of normal pan- creas in arterial phase and pancreatic parenchymal phase. Four patients showed mild high-density and 2, iso-density in the portal venous phase. CONCLUSION: Spiral CT multi-phase enhanced scan with 1.5 ml/kg contrast agent and 2-5 mm slice width can loca- lize functioning islet cell tumors accurately.

关键词： islet cell tumor spiral CT enhanced scan

Synthesis,Crystal Structures,DNA Cleaving and Binding Activities of CuⅡ,NiⅡ,ZnⅡ,CoⅡ,and MnⅡComplexes derived from 4-Carboxy-1-(4-carboxybenzyl)pyridinium bromide

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Synthesis,Crystal Structures,DNA Cleaving and Binding Activi...

PI3K/AKT signaling and neuroprotection in ischemic stroke:molecular mechanisms and therapeutic perspectives

中国化学会第六届全国结构化学学术会议

作者： Jin-Xiang chen~*,Ming chen,Ming-Zhen chen,Chun-Qiong Zhou,wen-hua chen~* School of Pharmaceutical Sciences,Southern Medical University,Guangzhou 510515.

Identification of chemical species that are capable of binding to and cleaving DNA has important implications in new drug discovery,and therefore has been a hot topic in chemical ***,we describe the synthesis of a dicarboxylic ligand,HCcbpBr(Ccbp= 4-carboxy-1-(4-carboxybenzyl)pyridinium) and its five transition metal complexes,i.e.{[Cu(Cin)]·4HO}

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Neural Regeneration Research 2025年第10期20卷 2758-2775页

作者： Tianlong Liu Xiaolin Li Xiaowei Zhou Wei chen Aidong wen Minna Liu Yi Ding Department of Pharmacy Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina Department of Pharmacy The 940 Hospital of Joint Logistics Support Forces of Chinese PLALanzhouGansu ProvinceChina Department of Pharmacy The 944 Hospital of Joint Logistics Support Forces of Chinese PLAJiuquanGansu ProvinceChina Department of Nephrology The 940 Hospital of Joint Logistics Support Forces of Chinese PLALanzhouGansu ProvinceChina

It has been reported that the PI3K/AKT signaling pathway plays a key role in the pathogenesis of ischemic *** a result,the development of drugs targeting the PI3K/AKT signaling pathway has attracted increasing attention from *** article reviews the pathological mechanisms and advancements in research related to the signaling pathways in ischemic stroke,with a focus on the PI3K/AKT signaling *** key findings include the following:(1)The complex pathological mechanisms of ischemic stroke can be categorized into five major types:excitatory amino acid toxicity,Ca^(2+)overload,inflammatory response,oxidative stress,and apoptosis.(2)The PI3K/AKT-mediated signaling pathway is closely associated with the occurrence and progression of ischemic stroke,which primarily involves the NF-κB,NRF2,BCL-2,mTOR,and endothelial NOS signaling pathways.(3)Natural products,including flavonoids,quinones,alkaloids,phenylpropanoids,phenols,terpenoids,and iridoids,show great potential as candidate substances for the development of innovative anti-stroke medications.(4)Recently,novel therapeutic techniques,such as electroacupuncture and mesenchymal stem cell therapy,have demonstrated the potential to improve stroke outcomes by activating the PI3K/AKT signaling pathway,providing new possibilities for the treatment and rehabilitation of patients with ischemic *** investigations should focus on the direct regulatory mechanisms of drugs targeting the PI3K/AKT signaling pathway and their clinical translation to develop innovative treatment strategies for ischemic stroke.

关键词： apoptosis autophagy inflammation ischemic stroke neuroprotection oxidative stress pathogenesis phosphatidylinositol 3-kinase protein kinase B therapeutics

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分区分级双P型辐射管喷口结构位置特性

工程科学学报 2017年第5期39卷 756-761页

作者：徐钱冯俊小周闻华陈艳梅北京科技大学能源与环境学院北京100083

为了对分区分级双P型燃气辐射管喷口结构、位置进行优化,提高燃烧效率.首先对分区分级双P型燃气辐射管进行了实验和数值研究,结果发现,除NO_x体积分数的误差为11.6%外,其他参数的偏差都在1%以内,证明该模型具有可靠性.在此基础上,通过... 详细信息

为了对分区分级双P型燃气辐射管喷口结构、位置进行优化,提高燃烧效率.首先对分区分级双P型燃气辐射管进行了实验和数值研究,结果发现,除NO_x体积分数的误差为11.6%外,其他参数的偏差都在1%以内,证明该模型具有可靠性.在此基础上,通过研究主管和支管的喷口位置及喷口结构等参数,进行了气体温度和壁面温度的研究分析.结果显示:随着主管喷口位置向外移动,分区分级燃气辐射管表面温度的最高值逐渐减小,壁面温度的最低值逐渐增大.支管喷口位于三通管与支管交线处时,可以减少高温气体对辐射管管壁的冲击作用,提高支管径向的温度均匀性,延长辐射管使用寿命;主管喷口的形式为完全预混式喷口时,壁面温差最小;支管喷口的形式为不对称式时,分区分级燃气辐射管壁面温差最小,燃烧热效率最高.

关键词：辐射管喷嘴空燃比结构氮氧化物控制

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无人机污染源自主搜寻算法综述

中国科学：信息科学 2022年第9期52卷 1579-1597页

作者：李中国陈文华刘存佳 Department of Aeronautical and Automotive Engineering Loughborough UniversityLoughborough LE113TUUK

自主搜寻在环境保护、灾后搜救和工业监控等方面有重要作用.无人机传感平台凭借其灵活的机动性成为实现自主搜寻的有效途径之一.针对自主搜寻中两个关键任务,即污染源定位和污染边界跟踪,本文分别梳理了相关算法体系,并揭示了其设计思... 详细信息

自主搜寻在环境保护、灾后搜救和工业监控等方面有重要作用.无人机传感平台凭借其灵活的机动性成为实现自主搜寻的有效途径之一.针对自主搜寻中两个关键任务,即污染源定位和污染边界跟踪,本文分别梳理了相关算法体系,并揭示了其设计思想的本质.对于污染物溯源,控制驱动和信息驱动两类算法是目前的研究主流,但两者的结合却鲜有报道.在边界跟踪方面,本文从单平台和多平台协作两方面总结了现有文献的控制和估计方法.根据双重控制思想,本文分析了相关算法的设计思路,并展望了下一步的研究重点.

关键词：自主搜寻无人机污染源搜寻边界跟踪双重控制探索与利用

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中国煤中铍的分布赋存特征研究

燃料化学学报 2004年第2期32卷 155-159页

作者：白向飞李文华陈文敏煤炭科学研究总院北京煤化工研究分院北京100013

根据对中国不同矿区1018个煤层煤样和生产煤样铍含量数据的统计结果,分析了中国不同成煤时代、不同聚煤区煤中铍的分布特征。同时,根据对10个不同煤田煤样的实验室浮沉试验、煤岩分析等试验研究,运用Solari方法,计算了煤中各组分中铍的... 详细信息

根据对中国不同矿区1018个煤层煤样和生产煤样铍含量数据的统计结果,分析了中国不同成煤时代、不同聚煤区煤中铍的分布特征。同时,根据对10个不同煤田煤样的实验室浮沉试验、煤岩分析等试验研究,运用Solari方法,计算了煤中各组分中铍的理论含量,讨论了中国煤中铍的赋存特征,尤其是铍在各种煤岩组分中的分布。研究表明,铍在煤中富集程度较高,但相对于世界煤中平均水平来说,中国煤中铍含量总体水平较低。煤中铍主要赋存于惰质组及伊利石粘土矿物中,在镜质组及其它矿物中含量较低。同时,中国大多数煤中铍的有机亲和性指数较高,不利于选煤过程中铍的脱除。

关键词：煤铍分布赋存