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Rare Metals 2024年第4期43卷 1702-1712页

作者： Xuan liu Zi-Xia Lin Yin-Biao Shi Xiao-Yan Wang Ming-Ye Ding Xiao-Fei Yang College of Science Nanjing Forestry UniversityNanjing210037China Testing Center Yangzhou UniversityYangzhou225009China

Regulating luminescent dynamics of lanthanide-based luminescent materials via external stimuli is of great significance in the fields of optical thermometry and high-level ***,it is still a huge challenge to realize multimodal emissions with tunable color outputs from a single activator in simple structures via smart dynamic control of photon transition ***,we present a mechanistic strategy to achieve multimodal luminescence of Er^(3+)activators with color-switchable outputs in a non-core-shell *** the control of excitation dynamics(λ_(ex)=980,808,1532,377 nm),the population among the intermediate en ergy levels of Er^(3+)and the interaction between Er^(3+)and Yb^(3+)could be precisely modulated through energy transfer and migration processes,leading to the generation of colortunable multimodal luminescence upon diverse excitation modes(non-steady-state,single-/dual-wavelength steady,thermal activation).Inspired by its special luminescent performance,the as-obtained material exhibits great potential in noncontact thermometry,multimodal anticounterfeiting,and high-capacity information encryption by performing a series of proof-of-concept *** findings might provide a conceptual model to modulate the luminescent dynamics in a simple-structured system for the generation of color-adjustable multimodal emissions,which is convenient for the development of advanced luminescent materials toward versatile cuttingedge applications.

关键词： Lanthanide ions Multimodal emission Upconversion Downshifting Anti-counterfeiting Luminescent thermometry

Interface interaction between SiO_(2) and magnetite under high temperature:particle migration and inhibition mechanism

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Journal of Iron and Steel Research International 2024年第3期31卷 561-572页

作者： Yao-zu Wang Jian-liang Zhang Qiang Cheng Hui-qing Jiang Zheng-jian liu Yu-bo Tan School of Intelligent Science and Technology University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Advanced Engineering University of Science and Technology BeijingBeijing 100083China

Silicon is one of the main gangue components in iron ore,usually in the form of quartz and *** studies have shown that SiO_(2) has a two-sided effect on the consolidation of pellets during high-temperature oxidation roasting of ***,it is very difficult to capture the structural evolution and migration mechanisms during high-tem-perature roasting process by existing experimental ***,the influence of SiO_(2) on the consolidation behavior of magnetite was studied through a series of roasting experiments and molecular dynamic *** results show that the consolidation index and particle growth index decrease with the increase in SiO_(2) content in the *** 1573 K,the liquid phase promotes the recrystallization growth of hematite at high *** dynamic study shows that it is difficult for quartz SiO_(2) to form sintering neck with Fe_(2)O_(3).When the calcination temperature is higher than 1400 K,the Fe_(2)O_(3)-Fe_(2)SiO_(4) system produces a considerable sintering neck structure after *** atomic migration ability of Fe_(2)SiO_(4) is much higher than that of Fe_(2)O_(3).The higher atomic migration ability of Fe_(2)SiO_(4) is the main reason for the formation of the sintering neck.

关键词： Sintering neck Crystal growth Consolidation Molecular dynamics SiO_(2)

海洋环境用热轧304L不锈钢-A36碳钢复合钢板的腐蚀行为研究

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表面技术 2024年第14期53卷 75-86页

作者：刘叶诚郑志斌龙骏徐志彪郑开宏焦四海殷福星五邑大学轨道交通学院广东江门529000 广东省科学院新材料研究所国家钛及稀有金属粉末冶金工程技术研究中心广东省金属强韧化技术与应用重点实验室广州510650 广东省钢铁基复合材料工程研究中心广州510650 宝山钢铁股份有限公司上海201900

目的探究304L不锈钢和A36碳钢热轧复合钢板中不锈钢覆层、碳钢基体以及不锈钢-碳钢复合界面在海洋大气环境及海水浸没环境中的腐蚀行为与腐蚀机理。方法采用中性盐雾实验和电化学实验模拟了海洋大气环境及海水浸没环境,对304L不锈钢-A3... 详细信息

目的探究304L不锈钢和A36碳钢热轧复合钢板中不锈钢覆层、碳钢基体以及不锈钢-碳钢复合界面在海洋大气环境及海水浸没环境中的腐蚀行为与腐蚀机理。方法采用中性盐雾实验和电化学实验模拟了海洋大气环境及海水浸没环境,对304L不锈钢-A36碳钢热轧复合钢板的腐蚀机理进行了全面评估。利用扫描电子显微镜(SEM)和能量色散光谱(EDS)表征复合材料界面的微观结构和局部元素分布,使用X射线衍射仪(XRD)表征了腐蚀产物的成分和化合价。结果在复合界面上存在一个明显的元素过渡区域。2种钢复合界面结合平滑,结合质量良好,轧制对2种钢复合界面处的组织无明显影响。当中性盐雾实验进行到96 h时,复合界面的腐蚀速率开始超越碳钢基体的腐蚀速率。实验结束时,复合界面与碳钢基体的腐蚀失重量分别达到582g/m^(2)和468g/m^(2),复合界面在海洋大气环境中的腐蚀速率为碳钢基体的1.24倍。此外,在复合界面碳钢侧的腐蚀产物中观察到富氯层。在电化学实验中,复合界面显示出了比碳钢基体更小的阻抗,这使复合界面在海水浸没环境中的腐蚀速率为碳钢基体的1.13倍。在复合界面处发现电偶腐蚀效应,加速了A36碳钢侧的腐蚀。开路电位的测试结果表明,复合界面的开路电位与耐蚀性较差的碳钢的开路电位接近,不同不锈钢-碳钢面积比复合界面的开路电位变化较小。结论在不同海洋腐蚀环境中,复合界面的腐蚀速率均大于覆层及基体的腐蚀速率,在海洋大气环境中尤为严重,复合界面碳钢部分的小面积暴露将导致材料的耐腐蚀性严重下降,在实际工程使用中应避免复合界面,尤其是复合界面碳钢部分的直接暴露。

关键词：金属复合材料不锈钢碳钢腐蚀海洋环境

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Sensitivity impacts owing to the variations in the type of zero-range pairing forces on the fission properties using the density functional theory

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Nuclear Science and Techniques 2024年第3期35卷 198-207页

作者： Yang Su Ze-Yu Li Li-Le liu Guo-Xiang Dong Xiao-Bao Wang Yong-Jing Chen China Nuclear Data Center China Institute of Atomic EnergyBeijing 102413China School of Science Huzhou UniversityHuzhou 313000China

Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were *** volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov *** in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and *** fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap *** results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing *** on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data.

关键词： Nuclear fission Density functional theory Pairing force Potential energy surfaces Fission fragment distribution

基于结构方程模型的大兴安岭北部天然林林下草本物种多样性驱动力分析

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西北林学院学报 2024年第2期39卷 13-20页

作者：王子瑞妙文豪呼日查高明龙刘磊李岩付宇萨如拉内蒙古农业大学林学院内蒙古呼和浩特010019 内蒙古农业大学农学院内蒙古呼和浩特010019 北京林业大学生态与自然保护学院北京100083

林下草本层植物在森林群落结构稳定性的调节和生态功能的发挥上具有非常重要的作用,是森林生态系统不可或缺的组成部分。以大兴安岭北部天然林为研究对象,运用结构方程模型探究气候、土壤和林分空间结构等环境因子对林下草本物种多样性... 详细信息

林下草本层植物在森林群落结构稳定性的调节和生态功能的发挥上具有非常重要的作用,是森林生态系统不可或缺的组成部分。以大兴安岭北部天然林为研究对象,运用结构方程模型探究气候、土壤和林分空间结构等环境因子对林下草本物种多样性的相对重要性,并探讨影响因子之间存在的复杂关系对林下草本物种多样性的影响机理。结果表明,从整体上来看,气候、土壤和林分空间结构对林下草本物种多样性均有较强的影响作用,其中气候的影响强度最大,土壤次之,林分空间结构的影响作用最小。从中介效应上来看,气候变化会导致土壤和林分空间结构发生变化,进而影响林下草本物种多样性,除此之外,还发现林分空间结构的改变,也会导致土壤性质发生变化,进而影响林下草本物种多样性。从影响系数上来看,影响林下草本物种多样性的驱动因子因各影响因素的不同而存在差异,年均降水、有机碳含量、混交度是分别表征气候因子、土壤因子、林分空间结构影响林下草本物种多样性的主导因子。在大兴安岭林区开展林下草本物种多样性保护及修复工作时,可适当调整混交度,维持合理的林分结构,并综合考虑改善土壤养分的森林经营方案。

关键词：草本物种多样性结构方程模型驱动力分析林分空间结构大兴安岭北部

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2020-2023年山东省涉禽外环境禽流感病毒监测分析

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中国人兽共患病学报 2024年第8期40卷 768-773页

作者：吴巨龙宋绍霞何玉洁张淑孙林孙文魁刘倜寇增强山东省疾病预防控制中心济南250014

目的了解山东省涉禽场所外环境中禽流感病毒的污染情况,为人感染禽流感疫情的防控提供科学依据。方法2020-2023年从山东省16个地市4类涉禽场所采集外环境样本,使用实时荧光定量PCR法进行A型流感病毒核酸检测,阳性样本再进行H5、H7和H9... 详细信息

目的了解山东省涉禽场所外环境中禽流感病毒的污染情况,为人感染禽流感疫情的防控提供科学依据。方法2020-2023年从山东省16个地市4类涉禽场所采集外环境样本,使用实时荧光定量PCR法进行A型流感病毒核酸检测,阳性样本再进行H5、H7和H9亚型禽流感病毒的核酸分型,描述山东省涉禽外环境中禽流感病毒的流行病学特征,率间比较采用χ^(2)检验进行结果分析。结果2020-2023年,山东省涉禽场所共采集外环境标本6523份,检出禽流感病毒阳性1007份,阳性率为15.44%。H5、H7和H9亚型及混合感染均有检出,阳性标本中以H9亚型为主(88.48%)。不同地市阳性率差异较大(χ^(2)=431.956,P<0.001),其中阳性率最高的地市达28.93%。不同监测场所(χ^(2)=304.604,P<0.001)、不同类型样本(χ^(2)=109.678,P<0.001)、不同季度(χ^(2)=64.963,P<0.001)阳性率差异有统计学意义。其中,监测场所以城乡活禽市场阳性检出率(20.12%)最高,样本类型中宰杀或摆放禽肉案板表面擦拭标本阳性检出率(22.56%)高于其他样本,阳性检出率最高峰出现在春季(20.31%)。结论山东省涉禽外环境中普遍存在禽流感病毒污染,H9亚型为主要病原体,H5、H7亚型共流行,存在人感染禽流感的风险,应加强重点季节、重点地区、重点场所、重点环节的禽流感防控工作。

关键词：禽流感病毒外环境监测山东省

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A novel Tb^(3+) and Eu^(3+) co-doped dual-emitting phosphate K_(3)SrBi(P_(2)O_(7))_(2) phosphor for application in FIR thermometers

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Journal of Rare Earths 2024年第3期42卷 455-463,I0001页

作者： Baochen Wang Shifeng Sun Zeqi Li Zongwang Li Weiwei Lin Chao Zeng Yan-gai liu Ruiyu Mi School of Chemical and Environmental Engineering Anhui Polytechnic UniversityWuhu241000China State-Province Joint Engineering Laboratory of Zeolite Membrane Materials Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of EducationInstitute of Advanced MaterialsCollege of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of GeosciencesBeijing100083China

Rare earth co-doped phosphor for fluorescence intensity ratio(FIR) thermometer has gained increasing attention in recent years. Herein, the novel Tb^(3+)and Eu^(3+)co-doped K_(3)SrBi(P_(2)O_(7))_(2)(KSBP) phosphate phosphors were reported. The crystal structure of the title phosphor was determined using Rietveld refinement and proved to have a three-dimensional structure. The time-resolved spectroscopy reveals that there is almost no energy transfer between Tb^(3+)and Eu^(3+). More importantly, Tb^(3+)and Eu^(3+)emissions show different thermal quenching behaviors, which claims the potential of this material for application in optical thermometer. The FIR of the typical KSBP:0.02Tb^(3+),0.04Eu^(3+)sample demonstrates a polynomial relationship as a function of temperature and the absolute and relative sensitivity are0.025 K^(-1) and 0.59%/K, respectively. In general, our study reports a novel and potential KSBP:Tb^(3+),Eu^(3+)phosphate phosphor that is promising for use in high-sensitive FIR thermometers.

关键词： Phosphor Thermometer Fluorescence intensity ratio Thermal stability Rare earths

Investigating the Absorption and Desorption Behavior of Methylene Chloride in the Poly(aryl ether ketone) Film with Different Crystallinities

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Chinese Journal of Polymer Science 2024年第2期42卷 239-246,I0009页

作者： Hong-Ru Yang Jin-Dong Zhang Dong-Ting Gao Gang liu Chun-Hai Chen Jia-Nan Yao Center for Advanced Low-Dimension Materials State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai201620China

Poly(aryl ether keton e)(PAEK) films with different crystallinities were obtained by controlling the cooling rate,which were subjected to the absorption and desorption of methylene chloride(CH_(2)Cl_(2)).We employed attenuated total reflection Fourier transform infrared(ATR-FTIR)spectroscopy analyses to investigate the diffusion behavior of CH_(2)Cl_(2) in PAEK films with different *** to the Fickian diffusion model,the calculated diffu sion coefficients of CH_(2)Cl_(2) in PAEK films were observed to decrease with increasing *** effect of CH_(2)Cl_(2)absorption and desorption on the mechanical properties of PAEK films with different crystallinity was further analyzed using tensile *** tensile tests exhibited that CH_(2)Cl_(2) has two concurrent effects:plasticization and solvent-induced *** scanning calorimetry(DSC) and wide-angle X-ray diffraction(WXRD) techniques further confirmed solvent-induced crystallization *** results would be beneficial to understand the solvent resistance of PAEK materials and consequently provide the practical application conditions of PAEK with a theoretical basis.

关键词： Poly(aryl ether ketone) Diffusion behavior Infrared spectra Solvent-induced crystallization Mechanical properties

Fluorescent Double Network Hydrogels with Ionic Responsiveness and High Mechanical Properties for Visual Detection

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 487-496页

作者：郑湾 liu Lerong Lü Hanlin WANG Yuhang LI Feihu ZHANG Yixuan 陈艳军 WANG Yifeng School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

We developed a fluorescent double network hydrogel with ionic responsiveness and high mechanical properties for visual *** nanocomposite hydrogel of laponite and polyacrylamide serves as the first network,while the ionic cross-linked hydrogel of terbium ions and sodium alginate serves as the second *** double-network structure,the introduction of nanoparticles and the reversible ionic crosslinked interactions confer high mechanical properties to the *** ions are not only used as the ionic cross-linked points,but also used as green emitters to endow hydrogels with fluorescent *** the basis of the “antenna effect” of terbium ions and the ion exchange interaction,the fluorescence of the hydrogels can make selective responses to various ions(such as organic acid radical ions,transition metal ions) in aqueous solutions,which enables a convenient strategy for visual detection toward ***,the fluorescent double network hydrogel fabricated in this study is promising for use in the field of visual sensor detection.

关键词： visual detection ionic responsiveness fluorescent hydrogels double network hydrogels mechanical property

Reactive air wetting and brazing of Al_(2)O_(3) ceramics using Ag-Nb_(2)O_(5) filler: Performance and interfacial behavior

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Journal of Advanced Ceramics 2024年第2期13卷 135-142页

作者： Yudi Qiu Shunjian Xu Xiangzhao Zhang Mingfen Zhang Qinhan Guo Beiji Wang Guanjun Qiao Guiwu liu School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China School of Intelligent Manufacturing Huzhou CollegeHuzhou 313000China

We firstly performed the reactive air wetting and brazing of Al_(2)O_(3) ceramics using Ag-(0.5-12)Nb_(2)O_(5) fillers,where Nb_(2)O_(5) can react with liquid Ag and O2 from air to generate AgNbO_(3).The contact angle of the Ag-Nb_(2)O_(5)/Al_(2)O_(3) system almost linearly decreases from~71.6°to 32.5°with the Nb_(2)O_(5) content increasing,and the joint shear strength reaches the maximum of~65.1 MPa while employing the Ag-4Nb_(2)O_(5) filler,which are mainly related to the formation and distribution of the AgNbO_(3) phase at the ***,the interfacial bonding and electronic properties of related interfaces were investigated by first-principles *** calculated works of adhesion(Wa)of Ag(111)/Ag-O-AgNbO_(3)(001)and AgNbO_(3)(001)/Al_(2)O_(3)(100)interfaces are higher than that of the Ag(111)/Al_(2)O_(3)(110)interface,indicating good reliability of the Ag/AgNbO_(3)/Al_(2)O_(3) *** relatively large interfacial charge transfer indicates the formation of Ag-Ag,Al-O,and Ag-O bonds in the Ag/AgNbO_(3)/Al_(2)O_(3) structure,which can contribute to the interfacial bonding.

关键词： reactive air brazing(RAB) wettability microstructure shear strength first-principles calculations