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甘草中20种无机元素的测定及对有害元素的健康风险评估

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食品安全质量检测学报 2024年第8期15卷 281-291页

作者：李海燕尹盼盼彭腾腾马趣环马中森石晓峰甘肃省医学科学研究院兰州730000 甘肃中医药大学药学院兰州730000 陇西保和堂药业有限责任公司定西743000

目的测定甘草中无机元素含量,并对重金属及有害元素进行污染分析及健康风险评估。方法采用电感耦合等离子体质谱法及原子荧光光谱法测定甘草中的无机元素含量及数据分析。通过计算样品中Pb、Cd、As、Hg和Cu5种重金属及有害元素的单向污... 详细信息

目的测定甘草中无机元素含量,并对重金属及有害元素进行污染分析及健康风险评估。方法采用电感耦合等离子体质谱法及原子荧光光谱法测定甘草中的无机元素含量及数据分析。通过计算样品中Pb、Cd、As、Hg和Cu5种重金属及有害元素的单向污染指数和综合污染指数对其进行安全性评价,通过计算每日最大可耐受摄入量(maximum tolerable daily intake,EDI)、靶标危害系数(target hazard quotients,THQ)和致癌风险(carcinogenic risk,CR),对甘草中5种重金属元素和有害元素进行健康风险评估,计算出甘草中各重金属的推荐重金属限量值(maximumresiduelimit,MRL)。结果得到的各无机元素在各自范围内线性关系良好(0.9969≤R2≤0.9996),样品稳定性、重复性、加标回收率及仪器精密度良好;Cr、Mn、Ni、Cu、Rb、Sr和ba元素含量较高,并且各样品间各元素含量具有一致性和差异性;主成分分析中22个样品得到5个主成分,累计方差贡献率达84.308%,确定Ga、V、Cs、Se、Co、As、U、Ni、Cd和Hg是甘草的特征无机元素;相关性分析结果与主成分分析结果基本一致;健康风险评估结果显示甘草样品均对暴露人群无明显健康危害,其致癌风险也可忽略不计。结论本研究所建立的方法可有效进行甘草无机元素的测定及来源判别,并为甘草健康风险评估提供了科学依据。

关键词：甘草电感耦合等离子体质谱法原子荧光光谱法健康风险评估

Eu^(3+)ions grafted polyacrylonitrile nanofibers possessing enhanced fluorescence performance by introducing benzoic acid as assistant ligand

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Journal of Rare Earths 2022年第3期40卷 421-427,I0003页

作者： Ping Wu Qianli ma Wensheng yu Jinxian Wang Guixia Liu Xiangting Dong Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province Changchun University of Science and TechnologyChangchun 130022China

Eu^(3+) ions were grafted onto the surface of electrospun polyacrylonitrile(PAN)nanofibers through coordination effect between C≡N groups on PAN nanofibers and Eu^(3+) ions,and benzoic acid(ba)was introduced as an assistant *** impacts of concentrations of Eu^(3+) ions and ba,and reaction time on the properties of final products were *** results reveal that Eu^(3+) ions can be successfully grafted onto PAN nanofibers,but the fluorescence intensity of the obtained PAN@Eu^(3+) nanofibers is very *** ba is introduced as the assistant ligand,the fluorescence intensity of the obtained PAN@(Eu^(3+)/ba)nanofibers is greatly stronger than that of PAN@Eu^(3+)nanofibers,and meanwhile,concentration quenching effect of Eu^(3+) ions can be effectively ***,the superior structure of PAN@(Eu^(3+)/ba)nanofibers not only brings the effective utilization of precious elemental europium,but also guarantees high mechanical strength.

关键词： Electrospinning Polyacrylonitrile Nanofibers Fluorescence Rare earths

Structure,defects,and microwave dielectric properties of Al-doped and Al/Nd co-doped ba_(4)Nd_(9.33)Ti_(18)O_(54)ceramics

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Journal of Advanced Ceramics 2022年第4期11卷 629-640页

作者： Weijia GUO Zhiyu ma yu LUO yugu CHEN Zhenxing yUE Longtu LI State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Low-loss tungsten–bronze microwave dielectric ceramics are dielectric materials with potential application value for miniaturized dielectric filters and antennas in the fifth-generation(5G)communication *** this work,a novel Al/Nd co-doping method of ba_(4)Nd_(9.33)Ti_(18)O_(54)(BNT)ceramics with a chemical formula of ba_(4)Nd_(9.33+z/3)Ti_(18−z)Al_(z)O_(54)(BNT–AN,0≤z≤2)was proposed to improve the dielectric properties through structural and defect *** with Al-doped ceramics(ba_(4)Nd_(9.33)Ti_(18−z)Al_(4z/3)O_(54),BNT–A,0≤z≤2)for comparison,the ceramics were prepared by a solid state *** is found that Al/Nd co-doping method has a significant effect on improving the dielectric properties compared with Al *** the doping amount z increased,the relative dielectric constant(εr)and the temperature coefficient of resonant frequency(τf)of the ceramics decreased,and the Q×f values of the ceramics obviously increased when z≤*** microwave dielectric properties ofεr=72.2,Q×f=16,480 GHz,andτf=+14.3 ppm/℃were achieved in BNT–AN ceramics with z=*** spectroscopy and thermally stimulated depolarization current(TSDC)technique were firstly combined to analyze the structures and defects in microwave dielectric *** is shown that the improvement on Q×f values was originated from the decrease in the strength of the A-site cation vibration and the concentration of oxygen vacancies(VO××),demonstrating the effect and mechanism underlying for structural and defect modulation on the performance improvement of microwave dielectric ceramics.

关键词： microwave dielectric ceramics ba4Nd9.33Ti18O54(BNT) Al and Al/Nd doping structural and defect modulation

Progress in the development of the 122-type IBS wires

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Superconductivity 2022年第2期2卷 17-22页

作者： Xianping Zhang yanwei ma Key Laboratory of Applied Superconductivity Institute of Electrical EngineeringChinese Academy of SciencesBeijing 100190People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Institute of Electrical Engineering and Advanced Electromagnetic Drive Technology Qilu ZhongkeJinan 250013People’s Republic of China

Profit from their low anisotropy and high upper critical field,iron-based superconductors(IBSs)have great potential for high magnetic fields *** progress has been made for the current density improvement of(Sr,ba)0.6K0.4Fe2As2(122-type)IBS wires over the past fourteen *** this article,an overview of the preparation procedures and key issues affecting the critical current performance of 122-type IBS wires is given,to provide a fundamental understanding of what controls the transport critical current density of 122-type IBS ***,the recent developments for 122-type IBS wires are presented and future prospect and challenges in the development of 122-type IBS wires for practical applications are discussed.

关键词： Iron-based superconductor 122-type Wire Technique

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‘午夜’紫薇离体茎段快繁体系的建立

北方园艺 2024年第12期 52-58页

作者：马清清焦紫薇沈鸿明王国联赵雨顾翠花浙江农林大学风景园林与建筑学院浙江杭州311300 浙江农林大学浙江省园林植物种质创新与利用重点实验室浙江杭州311300 浙江农林大学南方园林植物种质创新与利用国家林业和草原局重点实验室浙江杭州311300 浙江森城种业有限公司浙江海宁314406

以紫薇新品种‘午夜’带腋芽的幼嫩茎段为外植体,采用正交实验法,研究了NaClO与C_(2)H_(5)OH不同组合的消毒时间对外植体污染及萌发的影响,探讨WPM、1/2MS及MS 3种基本培养基和6-ba、NAA不同浓度组合对‘午夜’紫薇嫩茎腋芽诱导和增殖... 详细信息

以紫薇新品种‘午夜’带腋芽的幼嫩茎段为外植体,采用正交实验法,研究了NaClO与C_(2)H_(5)OH不同组合的消毒时间对外植体污染及萌发的影响,探讨WPM、1/2MS及MS 3种基本培养基和6-ba、NAA不同浓度组合对‘午夜’紫薇嫩茎腋芽诱导和增殖的影响以及在3种基本培养基上和不同Iba浓度组合对‘午夜’紫薇生根的影响,以期为‘午夜’紫薇大量繁殖提供参考依据。结果表明:75%C_(2)H_(5)OH消毒时间为30 s,5%NaClO消毒时间为6 min时,污染率较低,为18.6%;WPM培养基适合‘午夜’紫薇的茎段腋芽诱导与增殖,当6-ba、NAA浓度分别为1.0、0.5 mg·L^(-1)时诱导率最高,达93.28%;当6-ba浓度为1.0 mg·L^(-1),NAA浓度为0.1 mg·L^(-1)时的增殖系数最高,为5.83;Iba浓度变化对‘午夜’紫薇生根影响显著,在1/2MS培养基中添加0.5 mg·L^(-1)Iba时生根率最高,为92.99%,且无菌苗生长情况较好;炼苗后将组培苗移栽到泥炭土∶珍珠岩∶蛭石为3∶1∶2的基质上,成活率高达91%。

关键词： ‘午夜’紫薇茎段腋芽诱导增殖生根

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高正加速度重复暴露环境对SD大鼠种植体骨结合的影响

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实用口腔医学杂志 2024年第2期40卷 204-209页

作者：周小妮刘向东纪英博黄帅宋应亮马威口颌系统重建与再生全国重点实验室国家口腔疾病临床医学研究中心陕西省口腔生物工程工程技术中心空军军医大学第三附属医院种植科西安710032 联勤保障部队第九二二医院口腔科

目的:以小动物离心机模拟飞行员高正加速度(+Gz)暴露环境,观察其对SD大鼠种植体骨结合的影响。方法:18只SD大鼠随机分为+Gz重复暴露组和对照组,每组9只,每只动物左右侧股骨远心端分别植入一枚纯钛种植体。术后24 h内实验组进入+Gz暴露环... 详细信息

目的:以小动物离心机模拟飞行员高正加速度(+Gz)暴露环境,观察其对SD大鼠种植体骨结合的影响。方法:18只SD大鼠随机分为+Gz重复暴露组和对照组,每组9只,每只动物左右侧股骨远心端分别植入一枚纯钛种植体。术后24 h内实验组进入+Gz暴露环境,4~9 G 1 G/s逐渐增加,每周3次,对照组不作特殊处理。分别于2、4、8周随机处死两组各3只动物取材,进行micro CT扫描、双荧光标记和组织学分析,观察种植体周围骨结合情况。结果:2周时,+Gz重复暴露组骨体积分数(BV/TV)、骨小梁数量(Tb.N)、新骨沉积速率(maR)、种植体-骨接触率(BIC)、种植体周围新骨生成量(ba)均显著低于对照组(PmaR、ba显著低于对照组(P<0.05);8周时两组各指标均无统计学差异。结论:种植体植入后即刻进入+Gz重复暴露环境使SD大鼠骨结合初期形成速度减缓;但随着+Gz加载时间的延长,这种不利影响逐渐消退,最终达到与对照组相似的骨结合情况。

关键词： +Gz重复暴露种植体骨结合

Liver injury associated with malva grandifolia

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Hepatobiliary & Pancreatic Diseases International 2010年第4期9卷 443-444页

作者： Ekiz F yüksel  ba■ar  oban ■ yüksel O Teber ma Department of Gastroenterology Diskapi yildirim Beyazit Educational and Research Hospital Department of Radiology Ankara Etlik Ihtisas Educational and Research Hospital

To the Editor: Dietary supplements and herbal products are an increasingly common source of drug-induced liver injury. An increasing number of case reports have suggested causative supplement-associated liver toxicity. [1] malva grandifolia is a plant which is frequently found in flower and vegetable gardens (Fig.). mallow products are used

关键词： Liver injury associated with malva grandifolia

Bilharzia Appendicitis: Incidence in a Commune in mali, about 3CAS

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Surgical Science 2024年第5期15卷 321-329页

作者： Souleymane Bingue Dembélé yely Dianessy Moussa Samake Abdou Guiré Siaka Konaté Ousmane Sy Boubacar yoro Sidibé Amadou maïga Thiorno Nadio Boubacar Karembe Amaguiré Saye Sirama Diarra Dorcas Sodjiné yede Issiaka Diarra Ibrahima maiga mahamane Dicko Moussa Konaté Aliou Bina Diarra bakary Tientigui Dembélé General Surgery Department of the District Hospital of Commune IV of bamako Bamako Mali Kolondié ba Reference Health Centre Sikasso Mali Epidemiology and Clinical Research Bamako Mali General Surgery Department of Gabriel Touré University Hospital Bamako Mali Ophthalmology Department of the District Hospital of Commune IV of bamako Bamako Mali Gynecology and Obstetrics Department of the District Hospital of Commune IV of bamako Bamako Mali Commune I of the District of bamako Reference Health Centre Bamako Mali Imaging Department of the District Hospital of Commune IV of bamako Bamako Mali Commune VI of the District of bamako Reference Health Centre Bamako Mali Anotomy-Pathology Department of the G Point University Hospital Bamako Mali

Appendicitis bilharzia is a very rare condition and we report 3 cases of this pathology that sense clinical and biological similarities with bacterial appendicitis. The etiological diagnosis was exclusively histopathological, this allowed to highlight eggs of Schistosome in the appendicular wall in the three patients. The surgical treatment was supplemented by a specific medical treatment based on praziquantel. The surgical suites were simple for 2 patients, complicated by superficial parietal suppuration in a patient.

关键词： Bilharzial Appendicitis Endemic Histopathology Specific Antiparasitic Treatment

杉木北带东区杉木人工林碳储量影响因素源解析

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生态学杂志 2024年第5期43卷 1477-1487页

作者：安晓圆陈辰张德婧宛慧茹吴毓煜马李璐唐雪海欧强新安徽农业大学林学与园林学院合肥230036

全球气候变化下碳储量的准确估算是当今世界的焦点问题。本文利用杉木气候敏感的区域——安徽省两大杉木人工林产区(大别山区以及皖南地区)80块受人为干扰较小、不同林龄序列的杉木人工林样地调查数据,采用随机森林算法(Random forest,... 详细信息

全球气候变化下碳储量的准确估算是当今世界的焦点问题。本文利用杉木气候敏感的区域——安徽省两大杉木人工林产区(大别山区以及皖南地区)80块受人为干扰较小、不同林龄序列的杉木人工林样地调查数据,采用随机森林算法(Random forest,RF)构建包含候选林分、立地和气候因子的碳储量(地上碳储量(Aboveground carbon storage,C_(a))、地下碳储量(Belowground carbon storage,C_(b))和总碳储量(Total carbon storage,C))模型,并基于最优模型厘清杉木北带东区杉木人工林碳储量(C_(a)、C_(b)和C)估算差异的来源,确定主导因子,量化影响因素对碳储量的影响程度及其影响方向,以了解气候变化对树木生长的影响。结果表明:林分因子是影响杉木北带东区杉木人工林碳储量(C_(a)、C_(b)和C)的主导因子,其相对重要性值均超过76%,其中林分断面积(ba)影响最大,C_(a)、C_(b)和C均随ba的增加而增加;气候因子是影响杉木人工林碳储量的第二大因子,其相对重要性值均不超过17%,其中降水季节性(Bio15)影响最大,C_(a)、C_(b)和C随Bio15的增加而略有降低;而立地因子对杉木人工林碳储量模型的解释能力有限,其相对重要性值均低于3%,C_(a)、C_(b)和C随立地因子的变化极小。

关键词：林分因子气候立地随机森林碳储量