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Journal of Rare Earths 2022年第5期40卷 709-716,I0002页

作者： Tian Tian Wei Liu Qi Liu yan Zhang Yaoqing Chu gan Liu Jiayue Xu Institute of Crystal Growth School of Materials Science and EngineeringShanghai Institute of TechnologyShanghai 201418China Jiangsu Technology Innovation&C-V2X Academy Co. Ltd.Nanjing 210014China

A series of new oxyapatite red phosphors Ca_(3) Y_(7)(BO_(4)) (SiO_(4))_(5) O doped with different concentrations of Eu^(3+)were successfully synthesized by high temperature solid state *** X-ray diffraction(XRD)Rietveld refinement results show that the structure of the phosphor belongs to space group P6_(3)/m and Eu^(3+)ion replaces Y^(3+)*** emission spectrum consists of the characteristic emission peaks corresponding to Eu^(3+)under the excitation of 274 nm and the dominant emission peak is at 614 nm(^(5)D_(0)→^(7)F_(2) of Eu^(3+)).The concentration quenching effect occurs and the optimized Eu^(3+)concentration is 4.0 mol%.The energy level diagram for luminous mechanism is also given and the non-radiative energy transfer mechanism between Eu^(3+)is mainly exchange *** CIE coordinate is close to the ideal red light and the color purity is higher than 99.79%.Moreover,the phosphor exhibits moderate thermal stability because the photoluminescence intensity at 423 K is still maintained at higher than 78.97%of that at room *** internal quantum efficiency of Ca_(3) Y_(7)(BO_(4)) (SiO_(4))_(5) O:4.0 mol%Eu^(3+)phosphor is 58.2%.A red light emitting diode(LED)device based on it can emit bright red *** CCT values of the device are basically unchanged when driven by various bias *** results show that Ca_(3) Y_(7)(BO_(4)) (SiO_(4))_(5) O:Eu^(3+)is a new type of oxyapatite red fluorescent material with good comprehensive performances.

关键词： Red phosphor Oxyapatite structure Eu3+ions doping LED device Rare earths

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随机激励下软弹簧杜芬系统的安全盆侵蚀

工程力学 2006年第6期23卷 30-34页

作者：甘春标浙江大学机械与能源工程学院力学系杭州310027

非线性振动系统中由于复杂动力学行为而导致安全盆边界出现分形的情况比较普遍。研究随机激励对软弹簧杜芬振子的安全盆的影响。通过对系统安全盆的描绘,利用龙格-库塔和蒙特-卡罗方法,给出了系统有正阻尼和无阻尼时高斯白噪声和有界噪... 详细信息

非线性振动系统中由于复杂动力学行为而导致安全盆边界出现分形的情况比较普遍。研究随机激励对软弹簧杜芬振子的安全盆的影响。通过对系统安全盆的描绘,利用龙格-库塔和蒙特-卡罗方法,给出了系统有正阻尼和无阻尼时高斯白噪声和有界噪声作用下安全盆的侵蚀状况。结果表明,类似于确定的谐和激励情形,安全盆的面积将随着随机外激励强度的增大而减少,无阻尼系统的安全盆的边界经高斯白噪声或有界噪声外激励的作用同样可出现分形形状。

关键词：软弹簧杜芬振子高斯白噪声有界噪声安全盆分形

Abiotic transformation of chlorinated organics at the active surface of iron-bearing minerals in soils and sediments

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Science China(Technological Sciences) 2024年第10期67卷 2991-3008页

作者： LI XuXin yan Chen ZENG YuXi LI WenBin PENG TianWei SONG biao ZHOU ChengYun College of Environmental Science and Engineering Hunan UniversityChangsha 410082China Key Laboratory of Environmental Biology and Pollution Control(Hunan University) Ministry of EducationChangsha 410082China

Chlorinated organic compounds are emerging pollutants of widespread concern because of their toxicity,bioaccumulation,persistence,and lack of adequate regulatory *** abiotic transformation,facilitated by iron-bearing minerals,is critical to their natural dissipation in soils and ***,further exploration is needed to understand their underlying mechanisms and potential engineering applications under different redox *** paper reviews the abiotic transformation behaviors and mechanisms of chlorinated organics at the active surface of iron-bearing minerals under anoxic and oxic conditions and summarizes the strategies for enhancing the abiotic transformation efficiency of chlorinated *** abiotic transformation rate under oxic conditions can be a few orders of magnitude higher than that under anoxic *** anoxic conditions,chlorinated organics undergo reductive dechlorination through reductive elimination,hydrogenolysis,dehydrohalogenation,and nucleophilic substitution.A close relationship between the abiotic transformation of chlorinated organics and the production of hydroxyl radicals by iron-bearing minerals under oxic conditions was *** active iron-bearing minerals,carbonaceous materials,and biological synergy can facilitate abiotic dechlorination under anoxic ***,the regulation of redox conditions,the introduction of ligands,and the utilization of coexisting anions are proposed to enhance oxidative *** study is expected to improve the comprehension of the abiotic degradation of chlorinated organics mediated by iron-bearing minerals and provide the theoretical foundation for developing new approaches aimed at addressing chlorinated organic pollution.

关键词： chlorinated organic compounds iron-bearing minerals dechlorination degradation remediation

Responses of soil aggregate stability and soil erosion resistance to different bedrock strata dip and land use types in the karst trough valley of Southwest China

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International Soil and Water Conservation Research 2024年第3期12卷 684-696页

作者： Fengling gan Hailong Shi Junfei Gou Linxing Zhang Quanhou Dai Youjin yan Institute for Forest Resources and Environment Research Center of Guizhou Province Plateau Mountain Forest Cultivation Key Laboratory of Guizhou ProvinceCollege of ForestryGuizhouUniversityGuiyang550025China Chongqing Key LaboratoryofSurface Process and Environment Remote Sensing inthe Three Gorges ReseroirArea Schoolof Geography and Tourism ScienceChongqing Normal UniversityChongqing401331China

Soil aggregate stability is an important index that reflects soil quality and anti-erosion ability and strongly affects soil processes and *** strata dips(dip and anti-dip slopes)and land use types primarily influence soil aggregate stability,whereas the detailed mechanisms are unclear in karst trough ***,to explore the effects of bedrock strata dip and land use type on soil aggregate stability in karst trough valleys,soils were collected from five major land use types(abandoned land,grassland,pepper fields,corn fields and forest)on dip and anti-dip *** soil was fractionated into macroaggregates and microaggrates using dry and wet sieving *** soil particle size distribu-tions in the macroaggregates and microaggregates were measured in conventional *** results showed significant differences in soil aggregate stability among different bedrock strata dips,slope positions,and land use types(P0.25 mm water-stable aggregates(85.31%)and mean weight diameter(2.67 mm)on the upper slope compared to that in the other slope positions of the dip *** addition,the dip slope had a higher percentage of aggregate destruction(35.57%)than the anti-dip slope(29.81%),and the soil erodibility factor value of the natural forest of the dip/anti-dip slope was significantly lower than that of the other land use types(P<0.05).When the content of large macroaggregates was larger,the soil macroaggregate weight was *** the failure rate of the soil aggregates was lower,the stability of the soil structure was ***,these results suggest that natural forests can significantly improve the stability of soil aggregates,thereby improving soil erosion ***,natural recovery measures should be implem

关键词： Karst trough valley Land use types Soil aggregate stability Bedrock strata dip

Evolution of the Mangrove Wetland since the Holocene:Current Progress and Future Perspectives

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Journal of Earth Science 2024年第5期35卷 1669-1678页

作者： Xueyan yan Xianzhong Ke Qinghua Li Yiqun gan Xianjun Xie Yamin Deng Geological Survey China University of GeosciencesWuhan 430074China Wuhan Center China Geological Survey(Central South China Innovation Center for Geosciences)Wuhan 430205China School of Environmental Studies China University of GeosciencesWuhan 430074China

Mangrove wetlands are among the four most productive tropical and subtropical *** are also a core component of the coastal blue carbon ecosystem,which is of great ecological significance to human beings,plants,animals,and the global carbon *** has been a global decrease in the distribution of mangrove forests,and their ecological function has gradually degenerated since the *** from coastal mangrove wetlands can provide records of climate change and human activities,and multiple proxies including palynology,leaf fossil,biomarkers,DNA,phytolith and stable isotopes,can be used to reconstruct the evolutionary stages of paleo-mangroves and to identify the effect of natural processes and human activities on the distribution and evolution of *** information can provide theoretical support for mangrove protection and for improving carbon sequestration *** paper summarizes and compares the multiple proxies for mangrove reconstruction,reviews progress in the study of natural succession of global mangroves since the Holocene,expands on the influence mechanisms of human activities on mangrove growth and development and uses past information to lay a foundation for a model to predict future mangrove development.

关键词： mangrove Holocene multiproxy sedimentary environment climate change environ-mental geology

Machine learning study on time-temperature-transformation diagram of carbon and low-alloy steel

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Journal of Iron and Steel Research International 2023年第5期30卷 1032-1041页

作者： Xiao-ya Huang biao Zhang Qiang Tian Hong-hui Wu Bin gan Zhong-nan Bi Wei-hua Xue Asad Ullah Hao Wang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Beihang UniversityBeijing 100191China High Temperature Materials Research Division Central Iron and Steel Research InstituteBeijing 100081China Beijing Advanced Innovation Center for Materials Genome Engineering Collaborative Innovation Center of Steel TechnologyUniversity of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Advanced High Temperature Materials Central Iron and Steel Research InstituteBeijing 100081China School of Materials Science and Engineering Liaoning Technical UniversityFuxin 123099LiaoningChina Department of Mathematical Sciences Karakoram International UniversityGilgit-Baltistan 15100Pakistan

Time-temperature-transformation(TTT)diagram plays a critical role in designing appropriate heat treatment process of steels by describing the relationship among holding time,temperature,and quantities of phase *** predictions for TTT diagrams of new steel rapidly and accurately is therefore of much practical importance,especially for costly and time-consuming experimental ***,TTT diagrams for carbon and low-alloy steels were predicted using machine learning *** commonly used machine learning(ML)algorithms,backpropagation artificial neural network(BP network),LibSVM,k-nearest neighbor,Bagging,and Random tree,were adopted to select appropriate models for the *** results illustrate that Bagging is the optimal model for the prediction of pearlite transformation and bainite transformation,and BP network is the optimal model for martensite ***,the ML framework composed of Bagging and BP network models was applied to predict the entire TTT ***,the ML models show superior performance on the prediction of testing samples than the commercial software JMatPro.

关键词： Time-temperature-transformation diagram Carbon steel Low-alloy steel Machine learning Prediction framework

Machine learning in materials genome initiative:A review

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Journal of Materials Science & Technology 2020年第22期54卷 113-122页

作者： Yingli Liu Chen Niu Zhuo Wang Yong gan yan Zhu Shuhong Sun Tao Shen Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming650500China Computer Technology Application Key Lab of Yunnan Province Kunming University of Science and TechnologyKunming650500China Light Alloy Research Institute Central South UniversityChangsha410083China Chinese Academy of Engineering Beijing100088China Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming650093China Chengdu MatAi Technology Co. LtdChengdu610041China

Discovering new materials with excellent performance is a hot issue in the materials genome *** experiments and calculations often waste large amounts of time and money and are also limited by various conditions. Therefore, it is imperative to develop a new method to accelerate the discovery and design of new materials. In recent years, material discovery and design methods using machine learning have attracted much attention from material experts and have made some progress. This review first outlines available materials database and material data analytics tools and then elaborates on the machine learning algorithms used in materials science. Next, the field of application of machine learning in materials science is summarized, focusing on the aspects of structure determination, performance prediction, fingerprint prediction, and new material discovery. Finally, the review points out the problems of data and machine learning in materials science and points to future research. Using machine learning algorithms, the authors hope to achieve amazing results in material discovery and design.

关键词： Materials genome initiative(MGI) Materials database Machine learning Materials properties prediction Materials design and discovery

Preliminary Investigation on the Causes of Odd Vibration of Buildings in Guilin City——a Study on the Resonance between Buildings and the Underlying Soil Layer

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Acta Geologica Sinica(English Edition) 2020年第1期94卷 152-161页

作者： ZHANG Fawang gan Fuping LUAN Song MENG yan ZHENG Zhijie LI Weixuan Institute of Karst Geology Chinese Academy of Geological SciencesGuilin 541004China

A residential building in Guilin City, China, underwent an up-and-down vibration with an amplitude of 2 cm. By eliminating several causes such as earthquake, wind and construction, in combination with the unique karst geological conditions of Guilin, it was inferred that the effect of turbulent karst water is the main contributor to the occurrence of this vibration. Therefore, a geophysical survey was undertaken on the vibration zone and its surroundings. The resutls suggest that the soil in the upper part of the karst grooves shows conspicuous traces of disturbance and the water content has low resistance. A comprehensive analysis indicates that there is a karst strong runoff zone beneath the area. According to the water level and water temperature data collected automatically by the instrument, it can be concluded that the groundwater level had changed significantly twice during this period, so it was determined that the denudation of groundwater strong runoff causes the overlying soil layer to collapse, forming a soil-water soft-flow material with mixed phase. Since the building in this area was supported by friction piles, the groundwater-soil soft-flow material with mixed phase has intense plasticity, and the up-and-down vibration resulted in the change of the friction piles, which caused the up-and-down vibration of the building structure.

关键词： karst building vibration groundwater strong runoff

Effects of HPV Pseudotype Virus in Cutting E6 Gene Selectively in SiHa Cells

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Current Medical Science 2018年第2期38卷 212-221页

作者： yan-xiang CHENG gan-tao CHEN Xiao yanG yan-qing WANG Li HONG Department of Gynecology and Obsteirics Renmin Hospital of Wuhan University Wuhan 430062 China Department of Gastroenterology Renmin Hospital of Wuhan University Wuhan 430062 China Department of Gastroenterology The Third Renmin Hospital of Xiantao City Xiantao 433000 China

The objectives of this study were to investigate the effects of the CRISPR/Cas9 system mediated by the HPV pseudotype virus on SiHa cytobiology behavior by cutting the HPV16 E6 gene selectively and to explore the role of this system in the treatment of cervical cancer. After designing specific gRNA sequences targeting HPV 16 E6, generating hCas9-EGFP and E6-gRNA-RFP plasmids, and preparing the pseudovirus of HPV16 carrying E6-gRNA and Cas9 plasmids, we determined the titer of the pseudotype virus using the TCID50 method. We obtained the pseudotype virus of HPV16 carrying E6-gRNA and Cas9 plasmids to transfect cervical cancer SiHa cells. Experimental subjects were divided into control group, empty virus group, E6-gRNA transfected group, Cas9 transfected group and Cas9＋E6-gRNA transfected group. The molecular size of the cutting sequence was detected using the T7E1 enzyme digestion method and agarose gel electrophoresis, and the cleavage function of CRISPR/Cas9 on the E6 gene was determined at the same time. RT-PCR and Western blotting were performed to detect the mRNA and protein expression levels of E6 in all the groups; the Transwell cell migration assay was performed to detect the cell migration ability and metastasis in all groups. Heterotopic transplantation tumors were incorporated into mice and were used to investigate the effects of the CRISPR/Cas9 system mediated by the HPV pseudovirus on the tumorigenic ability of SiHa cells by selectively cutting HPV16 E6. The HPV16 pseudotype virus carrying E6-gRNA and Cas9 plasmids could successfully infect SiHa cells, and there were two cutting zones in the Cas9＋E6- gRNA transfected group. However, the empty virus group, E6-gRNA transfected group and Cas9 transfected group had no corresponding zone. Compared with those in the control group, the empty virus group, E6-gRNA transfected group and Cas9 transfected group, the mRNA and protein expression levels of E6 in SiHa cells were downregulated in the Cas9＋E6-gRNA transfe

关键词： HPV pseudotype virus CRISPR/Cas9 E6 gene cervical cancer

双跨转子的随机不确定性非参数建模与可靠性分析（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2018年第3期19卷 189-202页

作者： Chun-biao gan Yue-hua WANG Shi-xi yanG State Key Laboratory of Fluid Power and Mechatronic Systems College of Mechanical Engineering Zhejiang University Hangzhou 310027 China Key Laboratory of Advanced Manufacturing Technology of Zhejiang Province College of Mechanical Engineering Zhejiang University Hangzhou 310027 China

目的:旋转机械由于工作环境复杂,在运行过程中会不可避免地受到各种不确定性因素的影响,从而引发转子系统的异常振动。因此,迫切需要对系统工作状态开展可靠性分析。本文将外部扰动不确定性与模型不确定性考虑在内,旨在建立转子系统运... 详细信息

目的:旋转机械由于工作环境复杂,在运行过程中会不可避免地受到各种不确定性因素的影响,从而引发转子系统的异常振动。因此,迫切需要对系统工作状态开展可靠性分析。本文将外部扰动不确定性与模型不确定性考虑在内,旨在建立转子系统运行状态的可靠性评估指标,丰富转子动力学理论体系,为工程应用提供参考。创新点:1.采用非参数法进行建模,能够将外部扰动不确定性与模型不确定性同时包含在内;2.在非参数建模基础上,结合响应谱分析法进行可靠性计算,可避免对系统先验知识的需求并降低计算过程的复杂性;3.将短周期预测理论扩展应用于可靠性分析验证。方法:1.借助非参数法建立转子系统的随机不确定性模型;2.结合响应谱分析法推导出系统可靠性指标计算式;3.采用短周期预测方法对模拟数据统计指标进行计算与验证。结论:1.本方法可用于评估大型复杂旋转机械系统的可靠性,尤其对于服役时间较长导致系统参数出现不确定性变化的情形;2.本研究结果可为大型复杂旋转机械的设计、运行和控制提供理论基础,同时也可以为其他类型机械设备的可靠性分析和预测方法提供参考。

关键词：随机不确定性非参数建模可靠性响应谱分析