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Advances of graphdiyne-supported metal catalysts in thermocatalytic reactions

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Nano Research 2024年第4期17卷 2223-2233页

作者： Jia Yu Yida Yang Yuliang li changyan Cao Weiguo Song Beijing National Laboratory for Molecular Sciences CAS Research/Education Center for Excellence in Molecular SciencesLaboratory of Molecular Nanostructures and NanotechnologyInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing National Laboratory for Molecular Sciences CAS Research/Education Center for Excellence in Molecular SciencesLaboratory of organic solidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

Supported metal catalysts are widely used in the modern chemical industry.The electronic interaction between supports and active components is of great significance for heterogeneous catalysis.Graphdiyne(GDY),a new type of carbon allotrope with sp-hybridized carbon atoms,πconjugate structure,and electron transmission capability,is a promising candidate as catalyst support.Recent years have witnessed the rapid progress of GDY-supported metal catalysts for different catalysis reactions.Considering that most processes in the current chemical industry are thermocatalytic reactions,we herein give an overview about the advances and particular characteristics of GDY-supported catalysts in these reactions.The geometric structure and electronic properties of GDY are first introduced.Then,the synthesis methods for GDY-supported metal catalysts and their applications in thermocatalytic reactions are discussed,in which the effect of electronic interaction on catalytic performance is highlighted.Finally,the current challenges and future directions of GDY-supported metal catalysts for thermocatalysis are proposed.It is expected that this review will enrich our understanding of the advances of GDY as a superior support for metal catalysts in thermocatalytic reactions.

关键词： graphdiyne metal catalysts thermocatalytic reactions heterogeneous catalysis

Characteristics of laser-induced breakdown spectroscopy of liquid slag

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Plasma Science and Technology 2024年第2期26卷 86-93页

作者：董长言于洪霞孙兰香李洋刘修业周平黄少文 State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016People's Republic of China Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016People's RepublicofChina Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169People's Republic of China Shenyang University of Technology Shenyang 110870People's Republic of China Shenyang ligong University Shenyang 1i0142People's Republic of China Shandong Iron and Steel Company Ltd. Jinan 271105People's Republic of China

Rapid online analysis of liquid slag is essential for optimizing the quality and energy efficiency of steel production. To investigate the key factors that affect the online measurement of refined slag using laser-induced breakdown spectroscopy(liBS), this study examined the effects of slag composition and temperature on the intensity and stability of the liBS spectra. The experimental temperature was controlled at three levels: 1350℃, 1400℃, and 1450℃. The results showed that slag composition and temperature significantly affected the intensity and stability of the liBS spectra. Increasing the Fe content and temperature in the slag reduces its viscosity, resulting in an enhanced intensity and stability of the liBS spectra. Additionally, 42 refined slag samples were quantitatively analyzed for Fe, Si, Ca, Mg, Al, and Mn at 1350℃, 1400℃, and 1450℃.The normalized full spectrum combined with partial least squares(PLS) quantification modeling was used, using the Ca Ⅱ 317.91 nm spectral line as an internal standard. The results show that using the internal standard normalization method can significantly reduce the influence of spectral fluctuations. Meanwhile, a temperature of 1450℃ has been found to yield superior results compared to both 1350℃ and 1400℃, and it is advantageous to conduct a quantitative analysis of the slag when it is in a “water-like” state with low viscosity.

关键词： laser-induced breakdown spectroscopy(liBS) slag temperature composition viscosity internal standard normalization partial least squares(PLS)

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乳酸菌对果蔬产品的抑菌机理及应用

中国食品学报 2024年第2期24卷 432-441页

作者：王璐蒋沙沙李德海孙常雁李书欣东北林业大学生命科学学院哈尔滨150040 哈尔滨理工大学材料科学与化学工程学院哈尔滨150080

随着人们对健康饮食的日益重视,果蔬产品作为重要的营养来源备受关注。然而,果蔬的保藏一直是个难题,传统的果蔬保鲜剂往往依赖于化学物质,其在提高保鲜效果的同时却也带来了潜在的风险和不良影响,因此在果蔬生产和分销链中开发绿色有... 详细信息

随着人们对健康饮食的日益重视,果蔬产品作为重要的营养来源备受关注。然而,果蔬的保藏一直是个难题,传统的果蔬保鲜剂往往依赖于化学物质,其在提高保鲜效果的同时却也带来了潜在的风险和不良影响,因此在果蔬生产和分销链中开发绿色有效的抗菌剂成为研究热点。近年来,利用乳酸菌来延缓果蔬腐败进程已引起研究人员的极大兴趣。乳酸菌可以减缓果蔬腐败,且没有重大不良反应,其作为果蔬防腐剂的应用潜力巨大。然而,乳酸菌的抑菌机理不明确,而且获得监管机构批准并可广泛用于商业用途的乳酸菌或其代谢产物数量仍然很少,导致其在果蔬保鲜贮藏中的应用还不够广泛。本文综述乳酸菌的抑菌机理、应用现状以及在抑制腐败菌方面的优势和局限性,总结近年有关乳酸菌作为果蔬产品抑菌剂的研究进展,并对乳酸菌的发展进行展望,为乳酸菌在果蔬保鲜中的应用提供理论依据。

关键词：果蔬乳酸菌乳酸菌代谢产物抑菌

Oxygen vacancy enhanced biomimetic superoxide dismutase activity of CeO_(2)-Gd nanozymes

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Journal of Rare Earths 2021年第9期39卷 1108-1116页

作者： Xiangcheng Shi Jingjie Yang Xintong Wen Fuii Tian changyan li College of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhot010021China Department of Chemistry National University of Singapore.Singapore 117543Singapore Key Laboratory of Medicinal and Edible Plants Resources of Hainan Province Hainan Vocational University of Science and TechnologyHaikou 571126China

Cerium oxide-based nanozymes have recently drawn much attention in the field of biomedical and antioxidant applications,because of their unique regenerative or autocatalytic properties.Herein,we studied the biomimetic superoxide dismutase(SOD)nanozymes CeO_(2)-Gd that combines the fluorescence properties of rare earth Gd with the antioxidant properties of CeO_(2)nanoparticles,which was prepared via facile route.The structure and composition of the CeO_(2)-Gd were measured and verified by X-ray powder diffraction(XRD),Raman spectroscopy,transmission electron microscopy(TEM),energydispersive X-ray spectroscopy(EDX),and X-ray electron spectroscopy(XPS).Confocal microscopy was used to image cells.Antioxidant performance and cell viability of these nanozymes were measured in vitro using BGC-803 cell.CeO_(2)-Gd nanozymes with a higher Ce^(3+)/Ce^(4+)ratio show higher superoxide dismutase(SOD)mimetic activity.Their antioxidant activity and fluorescence properties of CeO_(2)-Gd in BGC-803 cancer cells are enhanced by oxygen vacancies generated by doping rare-earth elements Gd.This work may guide the future design of CeO_(2)-Gd-based biomimetic nanozymes for anticancer and antioxidant applications.

关键词： Antioxidant enzyme CeO_(2)-Gd nanozymes Superoxide dismutase Biomimetic nanozymes Oxygen vacancy Rare earths

Ce(Ⅲ)-modulation over non-enzymatic Pt/CeO_(2)/GO biosensor with outstanding sensitivity and stability for lactic acid detection

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稀土学报:英文版 2023年第9期41卷 1437-1447,I0006页

作者： Luyao Zhang Fuli Tian Huan li Jiangman Meng Qi liu Xiaoqian Guo Yun Qiu Jun Zhang changyan li College of Chemistry and Chemical Engineering.Inner Mongolia University Hohhot 010021China Key Laboratory of Medicinal and Edible Plants Resources of Hainan Province Hainan Vocational University of Science and TechnologyHaikou 571126China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China

A series of non-enzymatic graphene functionalized biosensors was developed via deposition precipitation method for lactic acid(LA) detection,which we re characterized by transmission electron micro scopy(TEM),Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),gas chromatography-mass spectrometry,liquid chromatography-mass spectro metry,and proton nuclear magnetic re sonance(~1H NMR).The electrochemical performances of the non-enzymatic biosensors were measured by means of the electrochemical impedance spectroscopy(EIS) and cyclic voltammetry(CV) method.The comprehensive analysis of structures shows that Pt,CeO_(2),and GO components interact with each other.During the storing and releasing oxygen,the valence ratio of Ce^(3+)/Ce^(4+) and the number of oxygen vacancies in CeO_(2) change accordingly,which can be conducive to increasing electronic transmission capacity and finally leads to the improvement of electrocatalytic performance.Among them,the Pt/CeO_(2)/GO biosensor containing 0.47 at% platinum exhibits an excellent electrochemical detection performance with high sensitivity of 12.3 μA·L/(mmol·cm^(2)) and a low limit of detection(LOD) of 5.12 μmol/L in a wide linear range from 10 to 900 μmol/L.In addition,the proposed biosensor possesses a promising anti-interference capability,as well as high stability and good reproducibility,which was assessed by testing the cyclic voltammogram in 0.1 mol/L lactic acid one year later.The underlying mechanism was proposed for electrochemical oxidation of LA to carbon dioxide and acetic acid with the synergistic effect among Pt,CeO_(2),and GO.Furthermore,the results of the standard addition method in real samples(human serum and urine samples) reveal that the lactic acid detection of the non-enzymatic Pt/CeO_(2)/GO biosensor is accompanied by high reliability.Thus,it will be a valuable biosensor for in vitro detection of lactic acid level in clinical samples.

关键词： Non-enzymatic biosensor Lactic acid Graphene functionalized Pt/CeO_(2) Oxygen vacancy Synergistic effect Rare earths

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耐热Al-Ce合金的组织和力学性能

特种铸造及有色合金 2024年第2期44卷 222-227页

作者：肖昌焱林冲谭纬文李杰吴树森武汉工程大学机电工程学院化工装备强化与本质安全湖北省重点实验室武汉430205 华中科技大学材料科学与工程学院材料成形与模具技术全国重点实验室武汉430074

采用光学显微镜、扫描电镜、X射线衍射、能谱仪等手段,研究了Al-xCe(x=6,8,10,12,%,质量分数,下同)和Al-8Ce-yNi(y=2,3,4,5,6,%)合金的组织和力学性能。结果表明,随着Ce含量增加,Al-Ce二元合金中α-Al枝晶显著细化,共晶Al_(11)Ce_(3)相... 详细信息

采用光学显微镜、扫描电镜、X射线衍射、能谱仪等手段,研究了Al-xCe(x=6,8,10,12,%,质量分数,下同)和Al-8Ce-yNi(y=2,3,4,5,6,%)合金的组织和力学性能。结果表明,随着Ce含量增加,Al-Ce二元合金中α-Al枝晶显著细化,共晶Al_(11)Ce_(3)相体积分数增大;当Ce含量为12%时,生成了粗大的初生Al_(11)Ce_(3)相。随着Ni含量增加,Al-8Ce-yNi合金固液两相区变窄,α-Al晶体固液界面成分过冷程度增加,晶体分枝加快,这导致了α-Al枝晶尺寸明显减小,同时合金中出现了由Al_(3)Ni和Al_(11)Ce_(3)相构成的三元共晶团网状结构。Al-8Ce-yNi合金室温和350℃高温抗拉强度均随着Ni含量的增加而增大。当Ni含量为6%时,合金室温和350℃高温下抗拉强度均达到最大值,分别为189 MPa和72 MPa。

关键词：耐热Al-Ce合金组织力学性能

不同行业22~35岁女职工生育力状况调查与分析

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环境与职业医学 2024年第4期41卷 397-402页

作者：于常艳辛佳芮徐茗寇振霞俞文兰张美辨李雪霏中国疾病预防控制中心职业卫生与中毒控制所北京100050 甘肃省疾病预防控制中心职业卫生科甘肃兰州730000

[背景]随着人口老龄化的加剧,生育力下降问题受到广泛关注。研究发现其影响因素主要包括年龄、生育情况等,然而不同行业生育力状况尚缺乏基础性资料。[目的]了解不同行业22~35岁女职工生育力状况及其影响因素。[方法]采用分阶段抽样原则... 详细信息

[背景]随着人口老龄化的加剧,生育力下降问题受到广泛关注。研究发现其影响因素主要包括年龄、生育情况等,然而不同行业生育力状况尚缺乏基础性资料。[目的]了解不同行业22~35岁女职工生育力状况及其影响因素。[方法]采用分阶段抽样原则,于2020年7月—2021年2月选取女职工较集中的教育、医疗、金融、通信等行业22~35岁已婚有怀孕史的22 903名女职工进行横断面调查,调查内容包括女职工行业、人口学特征、妊娠史、妊娠等待时间(TTP)及其他影响因素。分别采用卡方检验、Cox比例风险回归分析生育力下降及其影响因素,并在控制影响因素后构建不同行业与生育力下降的Cox比例风险回归模型,比较分析不同行业间差别。[结果] 22 903名调查对象中,回收有效问卷19 194份,总有效率83.8%。22~35岁女职工6个月和12个月的累积妊娠率(CRP)分别为67.23%和91.33%。多因素分析显示,地区、年龄、文化程度、个人年收入、家务劳动时间、应对方式、怀孕及生育次数、自然流产次数是生育力下降的影响因素(P <0.05)。怀孕次数≥3和自然流产次数≥2的女职工生育力下降风险较高,风险比(HR)及其95%置信区间(CI)分别为0.633(0.582~0.688)和0.785(0.670~0.921)(P <0.01)。与教育行业比较,生育力下降风险较高的为医疗和金融行业,HR(95%CI)分别为0.876(0.834~0.920)和0.909(0.866~0.954)(P <0.05);校正地区、年龄等9个影响因素后,生育力下降风险仍较高,HR(95%CI)分别为0.899(0.852~0.948)和0.882(0.833~0.934)(P <0.05)。[结论]地区、年龄、文化程度、个人年收入、家务劳动时间、应对方式、怀孕及生育次数、自然流产次数是生育力下降的影响因素。与教育行业比较,生育力下降风险较高的为医疗和金融行业。

关键词：妊娠等待时间女职工生育力下降 Cox比例风险回归

巴沙木碳量子点的性能及其在荧光油墨中的应用

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林业工程学报 2024年第3期9卷 110-118页

作者：孙天懿胡妙言刘凯高秋杰郑晓凤吕毅涌徐长妍徐丽南京林业大学材料科学与工程学院南京林业大学江苏省林产品高效加工利用联合创新中心南京林业大学绿色生物质燃料与化学品江苏省重点实验室南京210037 2019年江苏省研究生工作站:靖江国林木业有限公司靖江214500

碳量子点是一种尺寸小于10 nm的荧光纳米材料,其因优异的发光特性,在多个领域尤其是防伪领域中备受关注,其制备方法也是多种多样。为探究不同方法所制碳量子点荧光特性的异同,以质轻、无毒害特性且自身含有硅元素的巴沙木包装废弃物作... 详细信息

碳量子点是一种尺寸小于10 nm的荧光纳米材料,其因优异的发光特性,在多个领域尤其是防伪领域中备受关注,其制备方法也是多种多样。为探究不同方法所制碳量子点荧光特性的异同,以质轻、无毒害特性且自身含有硅元素的巴沙木包装废弃物作为原材料,分别用一步水热法与微波法制备碳量子点,并分别命名为H-CQDs和M-CQDs。通过对所制碳量子点的物理形貌、组分以及荧光性能的分析得出,2种方法制得的巴沙木碳量子点在365 nm紫外灯照射下均可发出蓝色荧光,且H-CQDs的荧光强度最高可达M-CQDs的3倍。H-CQDs与M-CQDs的光学性能具有相似性,它们的发光颜色相同、峰形位置相近;但同时激发波长也存在一定差异,H-CQDs的含氧官能团数量明显多于M-CQDs,H-CQDs的荧光量子产率(2.82%)高于M-CQDs(1.61%),且光学性能更为优异。同时,利用可发出明亮蓝色荧光且荧光量子产率较高的H-CQDs配制荧光油墨,该油墨在紫外灯下显示出明显的蓝色荧光,这说明巴沙木碳量子点可成功配制出荧光油墨,为其在防伪方面的应用提供了可能。

关键词：碳量子点光学性能荧光油墨防伪巴沙木

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运用激光雷达扫描技术进行停车位调查

地理空间信息 2024年第3期22卷 87-90页

作者：方喜波李振王昌彦何航星际空间(天津)科技发展有限公司天津300384

城市停车位资源的基础空间数据一般采用人工传统测量与调查的方式获取,该方式工作量大、效率低、调查成果无法追溯,且人员在道路测量中存在安全隐患。鉴于此,以天津市南开区为例,利用车载和地面激光雷达扫描技术调查采集城市各类停车资... 详细信息

城市停车位资源的基础空间数据一般采用人工传统测量与调查的方式获取,该方式工作量大、效率低、调查成果无法追溯,且人员在道路测量中存在安全隐患。鉴于此,以天津市南开区为例,利用车载和地面激光雷达扫描技术调查采集城市各类停车资源,借助人工和自动提取技术提取现状各类停车位和桥下空间信息,并通过数据核查对各类现状停车资源进行修正,快速获取城市各类停车资源的基础信息数据。采用激光雷达扫描技术调查停车位可突破传统车位调查的作业模式,大大提高调查的速度与准确度,并保障人员安全和数据的可溯源性,为城市停车位现状资源调查提供了新的技术方案。

关键词：车位调查激光雷达扫描桥下空间