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Electrochemical synthesis of FeN_(x) doped carbon quantum dots for sensitive detection of Cu^(2+) ion

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Green Energy & Environment 2023年第1期8卷 141-150页

作者： Siyuan Sun Weijie Bao Fan yang xingru yan yang Sun Ge Zhang Wang yang Yongfeng Li State Key Laboratory of Heavy Oil Processing China University of PetroleumChangpingBeijing102249China

A novel strategy was developed to fabricate FeNx-doped carbon quantum dots(Fe-N-CQDs)to detect Cu^(2+) ions selectively as a fluorescence probe.The Fe-N-CQDs were synthesized by an efficient electrolysis of a carbon cloth electrode,which was coated with monoatomic ironanchored nitrogen-doped carbon(Fe-N-C).The obtained Fe-N-CQDs emitted blue fluorescence and possessed a quantum yield(QY)of 7.5%.An extremely wide linear relationship between the Cu^(2+) concentration and the fluorescence intensity was obtained in the range from 100 nmol L^(-1) to 1000 nmol L^(-1)(R^(2)=0.997),and the detection limit was calculated as 59 nmol L^(-1).Moreover,the Fe-N-CQDs demonstrated wide range pH compatibility between 2 and 13 due to the coordination between pyridine nitrogen and Fe^(3+),which dramatically reduced the affection of the protonation and deprotonation process between H^(+) and Fe-N-CQDs.It is notable that the Fe-N-CQDs exhibited a rapid response in Cu^(2+) detection,where stable quenching can be completed in 7 s.The mechanism of excellent selective detection of Cu^(2+) was revealed by energy level simulation that the LUMO level of Fe-N-CQDs(-4.37 eV)was close to the redox potential of Cu^(2+),thus facilitating the electron transport from Fe-N-CQDs to Cu^(2+).

关键词： Electrolysis FeNx-doped CQDs Cu2t detection pH compatibility Quick response

The preparation of whole sp-C composed alkyne rich carbon materials

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Nano Research 2023年第11期16卷 12618-12625页

作者： Deyi Zhang Ze yang Wenjing Liu xingru yan Qin Liu Xiaodong Li Changshui Huang Yuliang Li Beijing National Laboratory for Molecular Sciences Organic Solids LaboratoryInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101China

For the high content of sp-hybridized carbon atoms,carbyne based materials can express superior conductivity and ultra-high theoretical capacity,which are key factors of high-performance anode.However,the poor stability of synthetic intermediates and unwanted side reactions lead to huge challenge to synthesis carbyne alternating carbon–carbon triple and single bonds.Here,we rationally designed a smart“Greedy Snake”strategy to synthesize the alkyne rich carbon materials named Si capped alkyne rich carbon(Si-Alkyne-C)which comprised of sp-hybridized carbon atoms.The as-prepared Si-Alkyne-C generated on the copper surface through a carbon–carbon coupling,in which Si can effectively protect the intermediates generated by the reaction.The C–Si bond can constantly generate copper-alkyne intermediates to couple with other terminal alkynes to continuously elongate like"Greedy Snake",forming a long alkyne chain structure.The as-prepared Si-Alkyne-C can be applied as anode electrodes,exhibited very high reversible capacity of up to 2776 mAh/g at a current density of 50 mA/g and an average capacity around 1202 mAh/g at a high current density of 5000 mA/g for 5000 cycles,which are the best results among the reported carbon materials and better than many other anode materials.These results not only provide a facile strategy to prepare carbyne based materials,but also open a broad avenue for the preparation of high-capacity anode materials.

关键词： alkyne rich carbon materials sp-hybridized carbon anode material energy storage lithium storage

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固化渣土材料力学性能试验与微观机理研究

地下空间与工程学报 2024年第3期20卷 848-856,867页

作者：杨涛李幸孺刘帅磊赵浩闫美美西安工程大学城市规划与市政工程学院西安710048

城市地下空间的营造与开发会产生大量的盾构渣土,传统的渣土处理方式对生态环境和资源保护带来重大挑战,将胶凝材料和盾构渣土结合后制备的再生固化充填材料(RSS-ER)可有效地解决这一难题。在确定水固比为0.35前提下,选择矿粉、粉煤灰... 详细信息

城市地下空间的营造与开发会产生大量的盾构渣土,传统的渣土处理方式对生态环境和资源保护带来重大挑战,将胶凝材料和盾构渣土结合后制备的再生固化充填材料(RSS-ER)可有效地解决这一难题。在确定水固比为0.35前提下,选择矿粉、粉煤灰和硅粉进行不同的正交组合,并开展不同配合比RSS-ER的流动性试验、无侧限抗压强度试验及微观结构试验。研究表明:RSS的流动性可满足一般回填工程中对于充填材料的要求;RSS-ER的无侧限抗压强度与养护时间呈正向关系,且室内常温养护的试件强度高于水下养护的试件;渣土骨架间的孔隙被水化产物C-S-H凝胶和C-A-S-H凝胶充填,是RSS-ER整体性及强度得以提高的原因。

关键词：盾构渣土再生固化充填材料流动性无侧限抗压强度微观结构试验

Magnetic coupling engineered porous dielectric carbon within ultralow filler loading toward tunable and high-performance microwave absorption

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Journal of Materials Science & Technology 2021年第11期70卷 214-223页

作者： Wang yang Bo Jiang Zhihui Liu Rui Li Liqiang Hou Zhengxuan Li Yongli Duan xingru yan Fan yang Yongfeng Li State Key Laboratory of Heavy Oil Processing China University of Petroleum(Beijing)Changping 102249China

Developing microwave absorption(MA)materials with satisfied comprehensive performance is a great challenge for tackling severe electromagnetic pollution.In particular,the magnetic component/carbon hybrids absorbers always suffer from high filler loading.Herein,we propose a feasible strategy to construct hierarchical porous carbon with tightly embedded Ni nanoparticles(Ni@NPC).These highly dispersed Ni nanoparticles produce strong magnetic coupling networks to enhance magnetic loss abilities.Moreover,the interconnected hierarchical dielectric carbon network affords favorable dipolar/interfacial polarization,conduction loss,multiple reflection and scattering.Impressively,with an ultralow filler loading of 5 wt.%,the resultant Ni@NPC/paraffin composite achieves an excellent MA performance with a minimum reflection loss of as high as-72.4 dB and a broad absorption bandwidth of 5.0 GHz.This capability outperforms most current magnetic-dielectric hybrids counterparts.Furthermore,the MA capacity can be easily tuned with adjustments in thickness,content and type of magnetic material.Thus,this work opens up new avenues for the development of high-performance and lightweight MA materials.

关键词： Hierarchical porous carbon Magnetic nanoparticles Magnetic coupling Ultralow filler loading High-performance microwave absorption

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基于不同指标评价儿童抗菌药物使用情况

中国医院药学杂志 2024年第2期44卷 209-213页

作者：裴保方李燕邢亚兵陶兴茹郑州大学附属儿童医院药学部河南郑州450018

目的:基于不同指标评价儿童抗菌药物使用,为临床合理用药评价提供参考。方法:采用回顾性分析方法,抽取郑州大学附属儿童医院2022年4—9月份出院病历5984份,提取患儿基本资料和抗菌药物使用情况,统计分析抗菌药物使用率、用药适应证、治... 详细信息

目的:基于不同指标评价儿童抗菌药物使用,为临床合理用药评价提供参考。方法:采用回顾性分析方法,抽取郑州大学附属儿童医院2022年4—9月份出院病历5984份,提取患儿基本资料和抗菌药物使用情况,统计分析抗菌药物使用率、用药适应证、治疗天数、治疗时长及处方日剂量。结果:5984份病历中,抗菌药物使用率41.29%,其中,0~28 d患儿抗菌药物使用率为81.37%,住院时间超过30 d患儿抗菌药物使用率为92.43%;使用频次排名前3位的抗菌药物是第三代、第二代和第一代头孢菌素,使用率分别为42.78%、15.52%和10.95%。不同类别抗菌药物临床用药适应证有较大差别,第一代头孢菌素(327/335,97.61%)和第二代头孢菌素(220/475,46.32%)主要于围手术期预防使用,大环内酯类药物(176/187,94.16%)、青霉素类复方制剂(47/53,88.68%)和第三代头孢菌素(1119/1309,85.49%)主要用于社区获得性感染;抗菌药物每百人天治疗天数为48.16 DOTs,每百人天治疗时长为40.87 LOTs,DOT/LOT为1.18,每百人天治疗天数和每百人天治疗时长在不同年龄、住院时间和科室之间差异均存在统计学意义(P10岁儿童组处方日剂量接近于成人DDD,>10岁儿童组和0~28 d儿童组处方日剂量中位数比率因抗菌药物差异略有不同,最高为阿奇霉素(12),最低为头孢呋辛(6.82)。结论:除抗菌药物使用率评价指标之外,抗菌药物用药适应证、抗菌药物治疗天数和处方日剂量也可用于评价儿童抗菌药物使用。

关键词：抗菌药物儿童治疗天数治疗时长处方日剂量

微生态免疫制剂联合肠内营养支持对老年脑卒中患者肠道微生态的影响

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中国药物滥用防治杂志 2024年第1期30卷 111-114页

作者：王志闫星汝郝红郑州市第九人民医院药学部河南郑州450053 郑州颐和医院药学部河南郑州450018

目的:探讨微生态免疫制剂联合肠内营养支持(EN)对老年脑卒中患者肠道微生态的影响。方法:选取2021年1月—12月我院收治的70例老年脑卒中患者作为研究对象,采用随机数字表法分为研究组与对照组,各35例。对照组给予EN治疗,研究组给予微生... 详细信息

目的:探讨微生态免疫制剂联合肠内营养支持(EN)对老年脑卒中患者肠道微生态的影响。方法:选取2021年1月—12月我院收治的70例老年脑卒中患者作为研究对象,采用随机数字表法分为研究组与对照组,各35例。对照组给予EN治疗,研究组给予微生态免疫制剂联合EN治疗,比较两组营养状况、肠道菌群数量及肠道黏膜屏障指标。结果:治疗后,研究组营养风险筛查简表(NRS-2002)评分低于对照组,白蛋白(ALB)、血红蛋白(Hb)、前白蛋白(PA)水平高于对照组(P<0.05);研究组肠道乳酸杆菌及双歧杆菌数量多于对照组,肠杆菌及肠球菌数量少于对照组(P<0.05);研究组血清D-乳酸、内毒素、二胺氧化酶(DAO)、肠型脂肪酸结合蛋白(I-FABP)水平低于对照组(P<0.05)。结论:微生态免疫制剂联合EN可有效调节老年脑卒中患者的肠道菌群比例,增强肠道黏膜屏障功能,改善肠道微生态,降低营养不良发生风险,改善患者的营养状况。

关键词：老年脑卒中肠内营养支持微生态免疫制剂营养状况肠道微生态

两个多酸基镧系(Eu、Tb)双膦酸酯配合物的合成、物化性质和太赫兹时域光谱

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无机化学学报 2024年第1期40卷 135-144页

作者：侯川兵李樱雨迟婧怡丁延王志强韩洪亮李杏茹金琼花首都师范大学资源环境与旅游学院北京100048 首都师范大学化学系北京100048 元素有机化学国家重点实验室(南开大学) 天津300071 南开大学先进能源材料化学教育部重点实验室天津300071 中科院长春应用化学研究所稀土资源利用国家重点实验室长春130022

在乙腈和去离子水的混合溶剂中合成了2个新的多酸基镧系双膦酸酯配合物[Eu(L)_(4)]PW_(12)O_(40)·2CH_(3)CN (1)和[Tb(L)_(3)(H_(2)O)]PW_(12)O_(40)(2)(L=亚乙基二膦酸四乙酯),并通过单晶X射线衍射、元素分析、红外光谱、粉末X射线衍... 详细信息

在乙腈和去离子水的混合溶剂中合成了2个新的多酸基镧系双膦酸酯配合物[Eu(L)_(4)]PW_(12)O_(40)·2CH_(3)CN (1)和[Tb(L)_(3)(H_(2)O)]PW_(12)O_(40)(2)(L=亚乙基二膦酸四乙酯),并通过单晶X射线衍射、元素分析、红外光谱、粉末X射线衍射、热重分析和太赫兹时域光谱对2个配合物的性质进行了表征,分析了配合物的晶体结构及分子间弱作用力,研究了配合物的发光等性能。单晶结构表明,配合物1是以Eu(Ⅲ)为中心、L为配体螯合形成的扭曲四方反棱柱结构。配合物2是以Tb(Ⅲ)为中心、L和H_(2)O为配体形成的扭曲单帽八面体结构。发光光谱表明配合物1和2所有的发射峰来源于金属内部的电荷迁移。此外,太赫兹时域光谱对配合物1和2的结构和发光的分析提供了帮助。

关键词：镧系配合物荧光光谱多金属氧酸盐太赫兹技术

三级医院预检分诊护士自我表露、职业幸福感与留职意愿关系研究

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中国医院统计 2024年第3期31卷 207-212,218页

作者：张俞代满香隋彦邓成梦刘春兰陈星儒赵晓敏中国人民解放军联勤保障部队第九七〇医院山东威海264200 滨州医学院护理学院山东烟台264000

目的了解三级医院预检分诊护士留职意愿现状,并探讨其与自我表露、职业幸福感的关系,为降低预检分诊护士离职率提供参考。方法采用便利抽样法,于2022年9月选取某省5所三级医院的230名预检分诊护士作为研究对象,采用一般资料调查问卷、... 详细信息

目的了解三级医院预检分诊护士留职意愿现状,并探讨其与自我表露、职业幸福感的关系,为降低预检分诊护士离职率提供参考。方法采用便利抽样法,于2022年9月选取某省5所三级医院的230名预检分诊护士作为研究对象,采用一般资料调查问卷、护士留职意愿量表、痛苦表露指数量表、医务工作者职业幸福感量表进行在线调查。结果预检分诊护士留职意愿总分为(22.56±4.38)分,预检分诊护士留职意愿与自我表露、职业幸福感存在正相关(r1=0.206,r2=0.679,P<0.001);多元线性回归分析显示,专业喜爱度、护患关系、职业幸福感是护士留职意愿的主要影响因素(R2=0.557,P<0.001)。结论三级医院预检分诊护士的留职意愿处于中等水平,有很大提升空间,医院管理者可通过提高预检分诊护士的专业喜爱度和职业幸福感,以增强其留职意愿。

关键词：预检分诊护士留职意愿自我表露职业幸福感

Polybrominated diphenyl ethers in chicken tissues and eggs from an electronic waste recycling area in southeast China

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Journal of Environmental Sciences 2011年第1期23卷 133-138页

作者： Xiaofei Qin Zhanfen Qin yan Li Yaxian Zhao Xijuan Xia Shishuai yan Mi Tian xingru Zhao Xiaobai Xu Yongjian yang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China Chinese Research Academy of Environmental Sciences Beijing 100012 China Taizhou No. 1 Middle School Taizhou 318000 China

The levels and distributions of polybrominated diphenyl ethers （PBDEs） in chicken tissues from an electronic waste （e-waste） recycling area in southeast China were investigated. Human dietary intake by local residents via chicken muscle and eggs was estimated. The mean PBDEs concentrations in tissues ranged from 15.2 to 3138.1 ng/g lipid weight （lw） and in egg the concentration was 563.5 ng/g lw. The results showed that the level of total PBDEs （∑PBDEs） in the chicken tissue was 2-3 orders of magnitude higher than those reported in the literature. The large difference of ∑PBDEs concentrations between tissues confirmed that the distribution of PBDEs in tissues depend on tissue-specificity rather than the ＂lipid-compartment＂. BDE-209 was the predominant congener （82.5%- 94.7% of ∑PBDEs） in all chicken tissues except in brain （34.7% of ∑PBDEs）, which indicated that deca-BDE （the major commercial PBDE formulation comprising 65%-70% of total production） was major pollution source in this area and could be bioaccumulated in terrestrial animals. The dietary PBDEs intake of the local residents from chicken muscle and egg, assuming only local bred chickens and eggs were consumed, ranged from 2.2 to 22.5 ng/（day.kg body weight （bw）） with a mean value of 13.5 ng/（day-kg bw）, which was one order of magnitude higher than the value reported in previous studies for consumption of all foodstuffs.

关键词： polybrominated diphenyl ethers chicken egg bioaccumulation tissue distribution exposure risk