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聚合物刷型二齿硼酸配体吸附剂的制备及其对尿液中核苷的分离富集性能分析

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分析化学 2024年第3期52卷 409-418页

作者：贺茂芳王欣张育珍张博唐一梅张剑西安医学院药学院北华大学药学院

为提高硼亲和吸附剂的结合力和吸附容量，以丙烯酰胺为单体，通过原子转移自由基聚合反应在聚多巴胺磁性微球（Fe3O4@pDA）表面接枝富含氨基的聚合物刷，然后键合二齿硼酸配体，获得聚合物刷型二齿硼酸配体吸附剂（Fe3O4@pDA@p-DBA）。... 详细信息

为提高硼亲和吸附剂的结合力和吸附容量，以丙烯酰胺为单体，通过原子转移自由基聚合反应在聚多巴胺磁性微球（Fe3O4@pDA）表面接枝富含氨基的聚合物刷，然后键合二齿硼酸配体，获得聚合物刷型二齿硼酸配体吸附剂（Fe3O4@pDA@p-DBA）。利用红外光谱和X-射线光电子能谱对材料进行表征，并研究了材料的吸附性能。结果表明，吸附剂对顺式二羟基化合物具有较高的选择性，并且二齿硼酸配体吸附剂较单齿硼酸配体吸附剂（Fe3O4@pDA@p-BA）具有更高的亲和力和吸附容量，说明二齿硼酸配体对材料的亲和力和吸附容量有促进作用。静态等温吸附和动态吸附研究结果表明，此材料对核苷的吸附符合Freundlich拟合及准二级动力学方程，为多层吸附，其中化学吸附起主导作用。在中性至弱酸性条件下，此材料对顺式二羟基分子仍具有良好的吸附性，有利于生物样品的直接分离富集。当缓冲液pH=6.5时，对于浓度为1.0μg/mL的腺苷、鸟苷、胞苷和尿苷4种核苷混合溶液，最佳吸附剂质量为30.0 mg。最佳洗脱条件为0.5 mL 0.1 mol/L甲酸-甲醇（1∶1,V/V）混合溶液洗脱2次，每次洗脱5 min。将此吸附剂用于尿液中核苷的分离富集，利用高效液相色谱进行检测，检测出尿液中腺苷、鸟苷、胞苷和尿苷的含量分别为8.0、50.4、29.3和35.2 ng/mL，加标回收率为87.6%～107.3%，相对标准偏差为2.8%～9.2%，说明本方法的准确度较高，结果可靠。

关键词：二齿硼酸配体线性聚合物刷亲和力分离富集核苷

主动脉搏动指数对射血分数保留的心力衰竭患者无事件生存的影响及预测价值

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中华医学杂志 2024年第8期104卷 594-599页

作者：吴易航张宇辉张健中国医学科学院北京协和医学院国家心血管病中心阜外医院心血管疾病国家重点实验室心力衰竭中心，北京100037

目的探索主动脉搏动指数(API)对射血分数保留的心力衰竭(HFpEF)患者无事件生存的影响及预测价值。方法回顾性纳入2014年11月至2022年8月在中国医学科学院阜外医院心力衰竭中心行漂浮导管检查的121例HFpEF患者。API的计算公式为脉压差/... 详细信息

目的探索主动脉搏动指数(API)对射血分数保留的心力衰竭(HFpEF)患者无事件生存的影响及预测价值。方法回顾性纳入2014年11月至2022年8月在中国医学科学院阜外医院心力衰竭中心行漂浮导管检查的121例HFpEF患者。API的计算公式为脉压差/肺动脉楔压。根据基线API的三分位数值将患者分为API>3.77组(n=40)、1.893.77组(n=41)和API≤1.89组(n=40)3组。主要临床终点为无事件生存,定义为未发生全因死亡、心脏移植、左室辅助装置植入或因心力衰竭再住院等事件。比较3组患者临床资料的差异,采用Spearman相关性分析计算API与左心功能指标的相关性,多因素Cox比例风险回归模型分析API与HFpEF患者无事件生存的关系,受试者工作特征曲线计算API预测HFpEF患者无事件生存的曲线下面积(AUC)。定量资料采用M(Q_(1),Q_(3))表示。结果121例HFpEF患者的年龄为59.0(46.0,66.5)岁,其中男性占69.4%(84例)。API与左心每搏功(r=0.478,P3.77组N末端B型利钠肽原(NT-proBNP)水平[492(163,2776)比2962(722,5831)比3823(1419,10262)ng/L]、左房前后径[38(34,42)比43(39,48)比45(42,53)mm]、右房压[5(2,8)比8(4,13)比13(8,16)mmHg(1 mmHg=0.133 kPa)]、平均肺动脉压[15(11,20)比22(17,26)比33(26,37)mmHg]均低于1.893.77组和API≤1.89组(均P366.0(189.8,648.5)d,随访结束时共有51例患者达到主要临床终点。API>3.77组、1.893.77组、API≤1.89组患者的累积无事件发生率分别为77.5%、56.1%和40.0%(P35)为HFpEF患者无事件生存的相关因素。API预测无事件生存的AUC(95%CI)为0.700(0.607~0.793)(P3.28,灵敏度为80.4%,特异度为52.9%。结论API与左心功能指标具有相关性;API降低是HFpEF患者不良预后的相关因素;在NT-proBNP的基础上,API可提供额外的预测价值。

关键词：心力衰竭左心功能主动脉搏动指数血流动力学预后

Morphological Evolution of Nb_2O_5 in a Solvothermal Reaction: From Nb_2O_5 Grains to Nb_2O_5 Nanorods and Hexagonal Nb_2O_5 Nanoplatelets

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Journal of Wuhan University of Technology(Materials Science) 2009年第2期24卷 245-248页

作者：胡卫兵 School of Chemical and Environmental Engineering Hubei Institute for Nationalities Department of Physics Huazhong University of Science and Technology

Novel Nb2O5 nanorods and polygonal Nb2O5 platelets were generated by a simple solvothermal technique. The geometry evolution of the resultant Nb2O5 from amorphous nanoparticles to crystallized particles, from polygonal platelets to well-elongated nanorods was been studied in detail. The processing parameters, including the reaction temperature, reaction time, concentration of the precursors, and pH value of the solution, which affect the shape and size of the nanorods, were investigated. The Nb2O5 nanorods with different aspect ratios were examined by XRD, SEM and TEM. The experimental results show that Nb2O5 nanorod is the orthorhombic structure and well-crystallized. The growth of the nanorods follows their [001] direction. The successful generation of high quality Nb2O5 nanorods is not only important for transition metal oxide research, but also potentially important for further formation of new Nb-based 1-D nanostructures, such as NbS2 and NbN.

关键词： solvothermal morphological evolution Nb2O5 nanomateraials

合成酚类抗氧化剂在我国室内灰尘中的污染特征及人体暴露风险

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中国环境科学 2024年第4期44卷 2320-2326页

作者：张瑞琦张笑武栅杏张秋月汪玉孙红文河北工业大学能源与环境工程学院天津300401 南开大学环境科学与工程学院环境污染过程与基准教育部重点实验室天津300350

研究了来自我国17个省市的室内灰尘中13种合成酚类抗氧化剂(SPAs)及其4种转化产物污染特征.结果显示,我国室内灰尘中主要的SPAs污染物为传统SPAs 2,6-二叔丁基-4-甲基苯酚(BHT)和新型SPAs抗氧剂1010,两者的污染水平相当(BHT:165~1.10×1... 详细信息

研究了来自我国17个省市的室内灰尘中13种合成酚类抗氧化剂(SPAs)及其4种转化产物污染特征.结果显示,我国室内灰尘中主要的SPAs污染物为传统SPAs 2,6-二叔丁基-4-甲基苯酚(BHT)和新型SPAs抗氧剂1010,两者的污染水平相当(BHT:165~1.10×10^(3.ng/g;抗氧剂1010:62.0~2.37×10^(3.ng/g),其浓度水平分别占所研究的SPAs总浓度的37.4%和36.0%.首次在室内灰尘中发现了抗氧剂330的存在,浓度水平最高为12.7ng/g.此外,灰尘中出现了一定浓度的SPAs转化产物,其中醌/醇化产物和醛化产物的占比较大,达到35.8%和56.9%,说明室内灰尘上的SPAs有一定的转化潜力.SPAs在室内灰尘中的浓度与采样点的经济发达程度有一定关联,东南沿海城市的SPAs浓度水平较高.受不同地区气候、地理条件影响,SPAs的浓度和组成体现出较大的空间差异.每日摄入量的评估结果显示,在高暴露情况下,成人和儿童对SPAs每日摄入总量分别为1.01×10^(-3)~0.54ng/(kg bw·d)和4.52×10^(-3)~2.3.ng/(kg bw·d).虽然在目前的污染水平下,人们通过灰尘摄入途径的SPAs暴露量较小,但考虑到SPAs物质种类的快速更新换代和环境污染浓度的不断升高,其环境风险有待持续关注.

关键词：灰尘合成酚类抗氧化剂污染水平组成特征人体暴露风险评估

Engineering versatile Au-based catalysts for solar-to-fuel conversion

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能源化学:英文版 2023年第8期83卷 341-362,I0010页

作者： Chunhua Wang Hongwen zhang Feili Lai Zhirun Xie Yun Hau ng Bo Weng Xuejiao Wu Yuhe Liao Department of Chemistry KU LeuvenCelestijinenlaan 200F3001 LeuvenBelgium cMACS Department of Microbial and Molecular SystemsKU LeuvenCelestijnenlaan 200F3001 LeuvenBelgium School of Energy and Environment City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong 999077China Centre for Sustainable Catalysis and Engineering Faculty of Bioscience EngineeringKU Leuven3001 LeuvenBelgium Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640GuangdongChina

Gold(Au) nanostructures(NSs) have been widely employed as cocatalysts to improve the photoactivity of semiconductor materials, while a systematic summary of the engineering approaches of Au NSs to maximize the solar-to-fuel conversion efficiency is still lacking. In this review, the recently developed strategies for elevating the overall photocatalytic performance of Au-based catalysts and the deep physical chemistry mechanisms are highlighted. Firstly, the synthetic approaches of Au NSs are summarized, followed by an elaboration on their multiple functions in improving photoactivity. Afterward, modification strategies of Au NSs used to enhance the photocatalytic efficiency of Au-semiconductor composites,including controlling the Au NSs morphology, size, crystal phase, defect engineering, alloying with different metals, modulating interfacial interaction, and introducing an external field, are summarized and discussed independently. Additionally, advanced characterization techniques that can provide insights into the charge dynamics of the photocatalysts are introduced. Finally, we share our opinion on the challenges and outline potentially promising opportunities and directions for efficient Au-based photocatalysis research moving forward. We sincerely look forward to this review can deliver insightful views to design efficient Au-based photocatalysts and spur certain innovations to other metal-based catalysts.

关键词： Au nanostructures Modification strategies Semiconductor Photocatalysis Solar-to-fuel conversion

Structure and species composition of tree stands on verges and slopes along a major highway in Hong Kong

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林业研究:英文版 2023年第5期34卷 1347-1358页

作者： Louis Shing Him Lee Hao zhang Kathy Tze Kwun ng Shun Cheong Lo Alan Siu Lun Yu Faculty of Design and Environment Technological and HigherEducation Institute of Hong KongHong KongPeople’s Republic of China Landscape Division Highways DepartmentHong KongPeople’s Republic of China Greening Landscape and Tree Management SectionDevelopment BureauHong KongPeople’s Republic of China

Arboricultural research focusing on transport land use was lacking in Hong *** highway slopes were registered in the Systematic Identification of Maintenance Responsibility of Slopes in the Territory(SIMAR),abbreviated as SIMAR *** aimed to analyze patterns in the structure and species composition of the tree stock along a highway in Hong Kong and examined how a slope registration system could help explain the characteristics of urban *** 53 slopes and 52 verges along San Tin Highway,Hong Kong were randomly *** trees on each slope and verge were collectively sampled as a tree *** variables,namely tree abundance,species richness,maximum tree height,Shannon-Wiener diversity,Simpson's dominance,and Pielou's evenness were measured for each *** addition,a limited visual tree risk assessment was *** 7,209 trees in 23 species were *** richness was low,ranging from one to eight species per *** and non-SIMAR slopes were *** slopes had significantly higher species richness,diversity,evenness but lower dominance,with mean difference of 1.41 species,0.17,0.17 *** slopes were associated with lower tree risk *** training regression models,boosting as an ensemble method arbitrarily raised the explanatory power and the predictive accuracy of some *** height,length,angle and area could be significant predictors of the biodiversity-related *** research can sample more habitat characteristics related to the structure and species composition of slopes and verges which were important components of urban forestry.

关键词： Highway greenery Roadside tree management Tree risk assessment Monospecific urban forest Slope geophysical environment Urban forests

Localized Electrochemical Impedance Spectroscopy Study on the Corrosion Behavior of Fe-Cr Alloy in the Solution with Cl^- and SO_4^(2-)

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Journal of Wuhan University of Technology(Materials Science) 2012年第1期27卷 27-32页

作者： XIAO Kui zhang Xin D0ng Chaofang WEI Dan WAng Chen LI Xiaogang Advanced Material and Technology Institute University of Science&Technology BeijingBeijing 100083China Society Service Center China Association for Science and TechnologyBeijing 100081China Faculty of Metallurgical and Energy Engineering Kunmming University of Science and TechnologyKunming 650093China

The corrosion behaviors of Fe-Cr alloy under three different pH values solutions with C1- and SO42- were investigated by localized electrochemical impedance spectroscopy （LEIS） measurements and the corrosion products were analyzed by laser Raman spectrometry. The results show that the high corrosion resistance of Fe-Cr Alloy is attributed to a passive film which is formed more easily when the alloy contains a large quantity of Cr element. However, its corrosion resistance varies in the solutions with different pH values, especially in the initial corrosion. The average impedance values in neutral and alkaline solution are much higher than that in acidic solution because the passive film is more likely to dissolve in the acidic condition. Moreover, the destructive effect of C1- and SO42 ions on the passive film is also demonstrated in corrosion process through the change of the impedance value with the steeping time.

关键词： Fe-Cr Alloy localized electrochemical impedance spectroscopy (LEIS) corrosionproducts Raman spectroscopy

艾条和艾柱燃烧释放颗粒物PM_(1.0)中多环芳烃的散发特征及浓度预测

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建筑科学 2024年第8期40卷 173-184页

作者：张金萍张坤北京建筑大学环境与能源工程学院北京100044 北京建筑大学“供热供燃气通风及空调工程”北京市重点实验室北京100044

为了解艾条和艾柱燃烧释放颗粒物PM_(1.0)中多环芳烃(Polycyclic Aromatic Hydrocarbons,PAHs)的散发特征,选取具有不同储存年份和提纯比例的4种艾条和2种艾柱为研究对象,首先在换气次数为1次/h的8 m^(3)的洁净环境舱内分别点燃一定量... 详细信息

为了解艾条和艾柱燃烧释放颗粒物PM_(1.0)中多环芳烃(Polycyclic Aromatic Hydrocarbons,PAHs)的散发特征,选取具有不同储存年份和提纯比例的4种艾条和2种艾柱为研究对象,首先在换气次数为1次/h的8 m^(3)的洁净环境舱内分别点燃一定量的艾条或艾柱,等其燃烧结束并停止通风换气后对烟气中颗粒相PM_(1.0)进行采样,样品经提纯和GC-MS上机分析确定PM1.0中PAHs的含量。由PAHs含量确定艾条或艾柱燃烧释放PM_(1.0)中PAHs即(PM_(1.0))PAHs的最高浓度(也即平衡浓度),进而确定其散发因子和散发速率,分析艾条或艾柱固有的特征参数对PAHs散发量的影响,同时与来自文献的PM_(2.5)中PAHs的散发特征进行对比分析。对艾条和艾柱散发的(PM_(1.0))PAHs的毒性进行了分析,最后对不同体积及换气次数的实际房间苯并[a]芘的浓度进行预测。结果表明:(1)艾条和艾柱燃烧释放的(PM_(1.0))PAHs中的优势个体主要为菲、蒽和荧蒽,其中菲的平均占比达23.66%,4环PAHs(荧蒽、芘、苯并[a]蒽、)占比最高,达31.11%~61.49%,5环(苯并[b]荧蒽、苯并[k]荧蒽、苯并[a]芘、二苯并[a,h]蒽)和6环(茚并[1,2,3-cd]芘、苯并[g,h,i]苝)占比较小,且随提纯比例增大或年份的降低而升高;(2)艾条和艾柱(PM1.0)PAHs的散发因子均值分别为2.99μg/g和4.62μg/g,散发速率均值为6.51μg/(h·g)和26.79μg/(h·g),随年份及提纯比例的减小,散发因子和散发速率有增大趋势;(3)(PM_(1.0))PAHs的散发因子在(PM_(2.5))PAHs中的占比为78.90%~85.28%,散发速率占比为78.91%~85.15%,且高环PAHs在(PM_(1.0))PAHs中的占比高于(PM_(2.5))PAHs;(4)(PM1.0)PAHs的致癌和致突变毒性等效剂量为107.14~526.56 ng/g和110.12~585.62 ng/g,5~6环PAHs的致毒贡献率最高,控制苯并[a]芘等致毒优势个体排放可有效降致毒风险;(5)提高换气次数或房间体积均可降低苯并[a]芘浓度。房间体积为60 m^(3)时,当换气次数为12次/h时预测的艾条和艾柱苯并[a]芘峰值浓度分别为2.75 ng/m^(3)和4.69 ng/m^(3)。换气次数为6次/h时,分别为5.19 ng/m^(3)和8.36 ng/m^(3)。推荐在换气次数为12次/h的通风条件下,以艾条进行艾灸。

关键词：艾条和艾柱多环芳烃(PAHs) 散发因子散发速率毒性等效剂量浓度预测

High critical current density in Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12) electrolyte via interfacial engineering with complex hydride

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Rare Metals 2024年第2期43卷 692-701页

作者： Ying-Tong Lv Teng-Fei zhang Zhao-Tong Hu Guang-Lin Xia Ze-Ya Huang Zhen-Hua Liu Li-Hua Que Cai-Ting Yuan Fang-Qin Guo Takayuki Ichikawa Xue-Bin Yu College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing210016China Centre for Hydrogenergy College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing210016China Department of Materials Science Fudan UniversityShanghai200433China Graduate School of Advanced Science and Engineering Hiroshima University1-4-1 KagamiyamaHigashi-Hiroshima739-8527Japan

Garnet-type solid-state batteries(SSBs)are considered to be one of the most promising candidates to realize next-generation lithium metal batteries with high energy density and ***,the dendrite-induced short-circuit and the poor interfacial contact impeded the practical ***,interface engineering to achieve low interfacial resistance without high temperature calcination was developed,which Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)was simply coated with complex hydride(Li_(4)(BH_(4))_(3)I(3L1L))in various mass ratios n(Li_(4)(BH_(4))_(3)I)-(100−n)LLZTO(10≤n≤40).The interfacial conductivity increases by more than three orders of magnitude from 8.29×10^(−6)S·cm^(−1)to 1.10×10^(−2)S·cm^(−1).Symmetric Li cells exhibit a high critical current density(CCD)of 4.0 mA·cm^(−2) and an excellent cycling stability for 200 h at 4.0 mA·cm^(−2).SSBs with polymeric sulfur-polyacrylonitrile(SPAN)cathode achieve a high discharge capacity of 1149 mAh·g^(−1) with a capacity retention of 91%after 100 cycles(0.2 C).This attempt guides a simple yet efficient strategy for obtaining a stable Li/LLZTO interface,which would promote the development of solid-state batteries.

关键词： Hydrides Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO) Critical current density Solid-state electrolytes(SSEs) Lithium-sulfur batteries