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综合化学实验:DNA 8-分支纳米结构的制备及表征

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化学教育（中英文） 2024年第2期45卷 59-65页

作者：孙四娟赵家婷袁云兰雷鑫段金伟长安大学理学院陕西西安710064 陕西维世诺生物科技有限公司陕西西安710304

借助DNA分子良好的生物相容性和可编程性,科学家合成了各种各样的DNA纳米自组装结构,这些结构在分子检测、生物成像和药物运输等领域已经展现出极大的应用潜力,然而这一先进前沿研究领域在本科生教学实验中并未涉及。为了拓展学生的科... 详细信息

借助DNA分子良好的生物相容性和可编程性,科学家合成了各种各样的DNA纳米自组装结构,这些结构在分子检测、生物成像和药物运输等领域已经展现出极大的应用潜力,然而这一先进前沿研究领域在本科生教学实验中并未涉及。为了拓展学生的科研视野,激发学生科研兴趣,将DNA纳米技术的科研成果与PCR、紫外-可见分光光度计、聚丙烯酰胺凝胶电泳和凝胶成像分析相融合,开展了DNA纳米自组装结构的教学实验。通过本实验使学生了解了DNA分支纳米结构的制备、表征和检测,不仅丰富了本科生实验教学项目的内容,培养了学生创新思维能力,提升了学生的科研水平,而且扩宽了学生的眼界、激发了学生进行前沿科学研究的热情,对培养复合型人才具有非常重要的意义。

关键词： DNA分支结构 PCR 紫外-可见分光光度计聚丙烯酰胺凝胶电泳凝胶成像

A comparative study on the reactivity of cationic niobium clusters with nitrogen and oxygen

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Chinese Chemical Letters 2022年第2期33卷 1058-1064页

作者： Benben Huang Mengzhou Yang xin lei Wen Gan Zhixun Luo Beijing National Laboratory for Molecular Sciences(BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

We have prepared well-resolved Nb^(+)_(n)(n=1-10)clusters and report here an in-depth study on the es-sentially different reactivity with N_(2)and O_(2),by utilizing a multiple-ion laminar flow tube reactor in tandem with a customized triple quadrupole mass spectrometer(MIFT-TQMS).As results,the Nb^(+)_(n)clus-ters are found to readily react with N_(2)and form adsorption products Nb_(n)N^(+)_(2m);in contrast,the reactions with O_(2)give rise to Nb_(n)O^(+)_(1−4)products,and the odd-oxygen products indicate O-O bond dissociation,as well as increased mass abundance of NbO^(+)pertaining to oxygen-etching *** illustrate how N_(2) prefers a physical adsorption on Nb^(+)_(n)clusters with an end-on orientation for all the products,and allow for size-selective Nb^(+)_(n)clusters to act as electron donor or acceptor in forming Nb_(n)N^(+)_(2m).In contrast to these nitrides,the dioxides Nb_(n)O+2display much larger binding energies,with O_(2)always as an electron acceptor,corresponding to superoxide or peroxide states in the initial ***-of-states and orbital anal-yses show that the interactions between Nb^(+)_(n)and O_(2)are dominated by strongπ-backdonation indicative of incidental electron transfer;whereas weakπ-backdonation and simultaneousσdonation interactions exist in Nb_(n)N^(+)_(2).Further,reaction dynamics analysis illustrates the different interactions for N_(2)and O_(2) in approaching the Nb^(+)_(n)clusters,showing the energy diagrams for N_(2)adsorption and O-O bond dissoci-ation in producing odd-oxygen *** analyses with orbital correlation and donor-acceptor charge transfer are also performed,giving rise to full insights into the reactivities and interactions of such transition metal clusters with typical diatomic molecules.

关键词： Gas phase reaction Nb cluster Chemical adsorption Orbital analysis Energy decomposition analysis

Large-scale fabrication of decoupling coatings with promising robustness and superhydrophobicity for antifouling,drag reduction,and organic photodegradation

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Friction 2023年第5期11卷 716-736页

作者： lei xin Hao LI Jian GAO Zhongwei WANG KaiJie ZHOU Sirong YU School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China School of Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580China

It is still a challenge to achieve large-area preparation of robust superhydrophobic surfaces with strong mechanical ***,a simple and low-cost method to prepare robust decoupling superhydrophobic coatings on aluminum(Al)alloys substrate has been *** superhydrophobicity and robustness of decoupling coatings are realized by structuring surfaces at two different length scales,with nanostructures for superhydrophobicity and microstructures for *** prepared decoupling coating shows promising superhydrophobicity,with water contact angle(CA)of~158.4°and roll off angle(RA)of~3°.It also exhibits high repellency for impacting water ***,the decoupling coating processes outstanding adhesion strength on the substrate after tape-peeling and cross-cut tests,also with promising wear resistantance after sandpaper abrasion and wear *** friction coefficient of this decoupling coating is only~*** addition,the robust decoupling superhydrophobic coating is applied to underwater buoyancy enhancement and fluid resistance reduction(drag reduction rate~30.09%).This decoupling superhydrophobic coating also displays promising self-cleaning and antifouling ***,benefitting from the photocatalytic property of TiO2,this decoupling coating is also exploited for degrading organics to achieve seawater *** obtained decoupling superhydrophobic coating is expected to apply on other solids in marine fields,and the simple and eco-friendly method develops the potential practical application.

关键词： Superhydrophobic decoupling wear resistance drag reduction

衍生化-气相色谱-质谱法检测阿加曲班中氯甲酸异丁酯残留

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分析化学 2024年第1期52卷 113-120页

作者：钱冲马博凯牛闯刘珊珊黄雯雯勾新磊王尉张梅曹学丽北京工商大学轻工科学与工程学院北京食品营养与人类健康高精尖创新中心北京市科学技术研究院分析测试研究所(北京市理化分析测试中心) 有机材料检测技术与质量评价北京市重点实验室北京城市学院

基于衍生化反应，采用气相色谱-质谱联用方法(Gas chromatography-mass spectrometry, GC-MS)检测了阿加曲班原料药中残留的氯甲酸异丁酯(Isobutyl chloroformate, IBCF)。分别对提取和衍生试剂、衍生反应时间、定性和定量离子进行筛选... 详细信息

基于衍生化反应，采用气相色谱-质谱联用方法(Gas chromatography-mass spectrometry, GC-MS)检测了阿加曲班原料药中残留的氯甲酸异丁酯(Isobutyl chloroformate, IBCF)。分别对提取和衍生试剂、衍生反应时间、定性和定量离子进行筛选和优化，推测了衍生反应机理和特征碎片离子的碎裂机理。阿加曲班样品经甲醇溶解及提取，其中残留的IBCF与甲醇发生衍生反应，生成甲基异丁基碳酸酯(Methyl isobutyl carbonate,MIBCB)，室温静置衍生24 h后，IBCF完全转化为MIBCB，通过检测MIBCB间接实现了IBCF的准确测定。IBCF在25～500 ng/mL浓度范围内线性关系良好(R2=0.9999)，检出限(LOD,S/N=3)为0.75μg/g，定量限(LOQ,S/N=10)为2.50μg/g。低(2.50μg/g)、中(25.00μg/g)和高(50.00μg/g)3个浓度水平的加标回收率为95.2%～97.8%，相对标准偏差(Relative standard deviation, RSD)为2.0%～3.1%(n=6)。本方法的精密度良好，不同日期、不同实验人员测定加标样品溶液(25.00μg/g)结果的平均值为24.28μg/g, RSD为2.1%(n=12)。本方法的耐用性良好，测定条件的微小变动对结果影响较小，在原条件、初始柱温±5℃、升温速率±2℃/min和柱流量±0.1 mL/min的条件下分别对加标样品溶液(25.00μg/g)进行测定，检测结果为24.16μg/g, RSD为2.2%(n=7)。将本方法用于两家药业公司生产的8批次阿加曲班样品的检测，均未检出IBCF。本方法能同时实现阿加曲班的溶解以及IBCF的提取和衍生，操作简便、灵敏度高、基质效应低、结果准确可靠，为阿加曲班中IBCF残留的测定提供了有效方法。

关键词：阿加曲班氯甲酸异丁酯衍生反应气相色谱-质谱甲基异丁基碳酸酯

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Hydrodynamics of the Semi-Immersed Cylinder by Forced Oscillation Model Testing

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China Ocean Engineering 2018年第1期32卷 110-116页

作者： SONG Chun-hui FU Shi-xiao TANG Xiao-ying HU Ke MA lei-xin REN Tong-xin State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Shipand Deep-Sea Exploration Shanghai 200240China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Tianjin Research Institute for Water Transport Engineering Tianjin 300000China Massachusetts Institute of Technology CambridgeMA 02139USA

In this paper, the hydrodynamic coefficients of a horizontal semi-immersed cylinder in steady current and oscillatory flow combining with constant current are obtained via forced oscillation experiments in a towing tank. Three nondimensional parameters(Re, KC and Fr) are introduced to investigate their effects on the hydrodynamic *** experimental results show that overtopping is evident and dominates when the Reynolds number exceeds 5×105 in the experiment. Under steady current condition, overtopping increases the drag coefficient significantly at high Reynolds numbers. Under oscillatory flow with constant current condition, the added mass coefficient can even reach a maximum value about 3.5 due to overtopping while the influence of overtopping on the drag coefficient is minor.

关键词： semi-immersed cylinder hydrodynamic coefficient forced oscillation experiment overtopping

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水系钠离子电池正极材料研究进展

化学工程师 2024年第3期38卷 55-58,41页

作者：张欣蕾周子健高筠华北理工大学化学工程学院河北唐山063210

近年来,随着新能源行业不断发展,金属锂储备锐减和价格攀升使得二次电池转向其他金属离子电池发展,钠离子电池凭借储备丰富、价格低廉等优势成为良好的替代品。围绕水系钠离子电池正极材料的研究广泛开展,主要的正极材料包括过渡金属氧... 详细信息

近年来,随着新能源行业不断发展,金属锂储备锐减和价格攀升使得二次电池转向其他金属离子电池发展,钠离子电池凭借储备丰富、价格低廉等优势成为良好的替代品。围绕水系钠离子电池正极材料的研究广泛开展,主要的正极材料包括过渡金属氧化物、聚阴离子化合物以及普鲁士蓝类似物。本文总结介绍了不同材料的结构特征以及研究方向,并对水系钠离子电池正极材料的发展方向进行了展望。

关键词：水系钠离子电池正极材料过渡金属氧化物聚阴离子化合物普鲁士蓝类似物

茶摄入量与结直肠癌发病因果关系的孟德尔随机化研究

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现代预防医学 2024年第4期51卷 613-618+639页

作者：周应舒李鑫磊李汶龙刘培慧刘菲黑龙江省大庆市人民医院普外二科辽宁省葫芦岛市中心医院神经介入科中国医科大学基础研究院免疫学教研室

目的利用两样本孟德尔随机化研究茶摄入量与结直肠癌发病的因果关系。方法利用IEU OPEN GWAS公共数据库中的结直肠癌全基因组关联分析数据(GWAS ID:ieu-b-496 5)和茶摄入量全基因组关联分析数据(GWAS ID:ukb-b-606 6),汇总两个数据集... 详细信息

目的利用两样本孟德尔随机化研究茶摄入量与结直肠癌发病的因果关系。方法利用IEU OPEN GWAS公共数据库中的结直肠癌全基因组关联分析数据(GWAS ID:ieu-b-496 5)和茶摄入量全基因组关联分析数据(GWAS ID:ukb-b-606 6),汇总两个数据集，筛选与茶摄入量密切相关且独立的单核苷酸多态性(SNPs)作为工具变量(IVs),通过采用两样本孟德尔随机化中的MR-Egger、逆方差加权(IVW)、加权中位数法(Weighted Median)、简单模型(Simple Mode)和加权模型(Weighted Mode)五种方法进行茶摄入量与结直肠癌发病的因果分析的判断，采用OR以及95%CI判断茶摄入量与结直肠癌发病是否存在因果关系，利用MR-PRESSO进行离群值检验，采用IVW(Cochran Q检验)以及MR-Egger(Rücker Q检验)进行异质性分析，采用Egger-intercept进行多效性检验，通过留一法进行敏感性分析，采用漏斗图分析是否存在潜在偏倚。结果最终纳入39个SNPs, MR-PRESSO未发现离群SNPs,P=0.237>0.05;在因果关系的判定上：IVW(OR=0.996,95%CI:0.990～1.002,P=0.293),MR-Egger(OR=0.992,95%CI:0.977～1.007,P=0.293),Weighted Median(OR=0.997,95%CI:0.987～1.007,P=0.479),Simple Mode(OR=0.996,95%CI:0.976～1.017,P=0.724),Weighted Mode(OR=0.996,95%CI:0.985～1.007,P=0.473),上述结果显示：茶摄入量与结直肠癌发病无因果关系，在异质性检测中Cochran Q检验中P=0.181>0.05,Rücker Q检验中P=0.167>0.05,无显著异质性，Egger-intercept进行多效性检验P=0.489>0.05未见多效性，留一法逐个剔除，未见明显影响结果的SNPs,漏斗图基本对称，显示主结果可靠。结论茶摄入量与结直肠癌发病无因果关系。

关键词：孟德尔随机化茶摄入量结直肠癌因果关系预后

无控制点场景下基于多运动目标的卫星视频稳像算法

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计测技术 2024年第2期44卷 70-81页

作者：李睿瑄李峰辛蕾杨雪张南钱学森空间技术实验室北京100094

为了解决无控制点场景下现有卫星视频稳像算法失效的问题,提出了一种基于多运动目标的卫星视频稳像算法,该算法构建了目标检测、轨迹平滑和范数优化的框架,将多目标卡尔曼滤波、rlowess轨迹平滑与L1-L2范数优化相结合,最终实现卫星视频... 详细信息

为了解决无控制点场景下现有卫星视频稳像算法失效的问题,提出了一种基于多运动目标的卫星视频稳像算法,该算法构建了目标检测、轨迹平滑和范数优化的框架,将多目标卡尔曼滤波、rlowess轨迹平滑与L1-L2范数优化相结合,最终实现卫星视频稳像。利用海上多目标舰船观测数据集开展实验,结果表明基于多运动目标的卫星视频稳像算法在X、Y方向上的稳像误差均不超过0.3个像素,验证了该算法的有效性。本研究填补了无控制点场景下卫星视频稳像的技术空白,具有重要的工程应用价值。

关键词：无控制点场景卫星视频稳像多运动目标亚像元级卡尔曼滤波 rlowess平滑 L1-L2范数优化

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Enhanced electron transport through two-dimensional Ti_(3)C_(2) in dye-sensitized solar cells

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Rare Metals 2022年第9期41卷 3078-3085页

作者： Gang Wang Li-Jiao Ma Bing-xin lei Heng Wu Zhao-Qing Liu Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan Province Key Laboratory of Electrochemical Energy Storage and Light Energy Conversion Materials of Haikou CitySchool of Chemistry and Chemical EngineeringHainan Normal UniversityHaikou571158China School of Materials and Environment Guangxi University for NationalitiesNanning530006China Guangzhou Key Laboratory for Clean Energy and Materials Huangpu Hydrogen Innovation CenterInstitute of Clean Energy and MaterialsSchool of Chemistry and Chemical EngineeringGuangzhou UniversityGuangzhou510006China

Two-dimensional(2D)Ti_(3)C_(2) material has a wide range of photovoltaic applications due to its unique electronic,optical,and plasmonic ***,we present a series of Ti_(3)C_(2)(0,0.6,0.8;wt%)nanosheets-modified P25 nanoparticles as photoanode films for dye-sensitized solar cells(DSSCs).The DSSC based on P25 and 0.6 wt%Ti_(3)C_(2) photoanode achieves a fairly good efficiency(9.22%),which greatly exceeds the counterpart based on the pure P25(7.16%).Benefiting from high light scattering and metallic electrical conductivity of Ti_(3)C_(2) additive,the P25/Ti_(3)C_(2)-based DSSC exhibits a superior behavior of controlling photogenerated charge recombination compared with pure P25 one.

关键词： Ti3C2 Conductivity Charge transfer Dyesensitized solar cells