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CMS实验中大动量玻色子喷注探针方法的发展及应用

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科学通报 2024年第22期69卷 3208-3221页

作者：高乐耘付大为赵宇哲郭启隆钱思天杨天一邓森李强北京大学核物理与核技术国家重点实验室北京100871

过去10余年来,大动量玻色子喷注的标记方法受到高能物理理论及实验界的极大关注,已经成为高能量物理前沿领域的推动技术和创新亮点.大动量玻色子常常作为共振产生的重粒子的衰变产物,广泛出现于超出标准模型的新粒子和新物理的寻找工作... 详细信息

过去10余年来,大动量玻色子喷注的标记方法受到高能物理理论及实验界的极大关注,已经成为高能量物理前沿领域的推动技术和创新亮点.大动量玻色子常常作为共振产生的重粒子的衰变产物,广泛出现于超出标准模型的新粒子和新物理的寻找工作中.对大动量的规范玻色子(统称为V)和希格斯玻色子(H),CMS实验组成功开发了V→qq和H→bb等过程的标记技术及校准方案,并成功将其应用于多玻色子共振态的寻找等工作中.本文回顾了10余年来CMS实验中大动量玻色子探针方法的发展及应用,其中包括最新提出的新技术和新方法,特别是人工智能时代到来后出现的与深度学习紧密结合的喷注标记技术.

关键词： CMS实验大动量玻色子探针超出标准模型的新物理深度学习

High-temperature dielectric switch and second harmonic generation integrated in a stimulus responsive material

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Chinese Chemical Letters 2021年第1期32卷 539-542页

作者： Yingsong Xue Zhixu Zhang Pingping Shi Wanying Zhang Qiong Ye dawei fu Ordered Matter Science Research Center Jiangsu Key Laboratory for Science and Applications of Molecular FerroelectricsSoutheast UniversityNanjing 211189China

Stimulus re s ponsive materials can provide a variety of desirable properties in one equipment unit,such as optoelectronic devices,data communications,actuators,memories,sensors and ***,it remains a large challenge to design such stimulus responsive materials,especially functional materials having both dielectric switch and second harmonic generation(SHG).Here,a new stimuli-responsive switchable material [(CH_(3))_(3)N(CH_(2))_(2)Cl]_(2)]Mn(SCN)_(4)(H_(2)O)_(2)] was discovered as a potential secondharmonic generation(SHG) dielectric *** is worth noting that it has SHG characteristics before and after undergoing reversible high-temperature phase *** this work,we successfully refined the tetramethylammonium cation to obtain a quasi-spherical cation,which is tetramethylchloroethylamine(TMCEM) *** substituting H with a halogen,the increased steric hindrance of the molecular makes energy barrier increased,resulting in the reversible high-temperature phase *** the same time,the interactions of quasi-spherical cations and [Mn(SCN)_(4)(H_(2)O)_(2)]^(2-) anions affect a noncentrosymmetric structure to induce the SHG *** findings provide a new approach to design novel functional switch materials.

关键词： Dielectric switch Second harmonic generation High-temperature Phase transition Stimulus responsive material

Lead-free bilayer heterometallic halide perovskite with reversible phase transition and photoluminescence properties

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Chinese Chemical Letters 2023年第4期34卷 590-594页

作者： Qiangqiang Jia Ting Shao Liang Tong Changyuan Su dawei fu Haifeng Lu Institute for Science and Applications of Molecular Ferroelectrics Key Laboratory of the Ministry of Education for Advanced Catalysis MaterialsZhejiang Normal UniversityJinhua 321004China Ordered Matter Science Research Center Jiangsu Key Laboratory for Science and Applications of Molecular FerroelectricsSoutheast UniversityNanjing 211189China School of Environment and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212002China

The layered heterometallic halide perovskites, as a newly explored material, have attracted great scientific attention. As one of the representatives of perovskite, lead-free or lead-substituted perovskite materials are widely applied in photovoltaic, sensors, catalysis, detectors and other fields. Therefore, it is urgent to carry out more systematic exploration and expand applicable preresearch, so as to make more interesting discoveries in this new hot spot. As an interesting candidate, heterometallic compounds will introduce more structural adjustability and novel physical properties, which is the main feature to be selected as the research hotspot. Here, we reported a lead-free bilayer heterometallic Ruddlesden-Popper(RP) type perovskite, [(MACH)_(2)CsAgBiBr_(7)](MACH = cyclohexanemethylamine), which possesses a reversible phase transition at 379.6 K/375.1 K during heating-cooling cycle. Besides, it exhibits reddish-brown light emission under 365 nm, meanwhile, CIE chromaticity coordinate is(0.32, 0.45) on the yellow side and correlated color temperature is about 6000 K. Moreover, both the experimental data and theoretical calculation results suggest that [(MACH)_(2)CsAgBiBr_(7)] shows indirect semiconducting characteristics. In summary, this work will inspire the design of lead-free heterometallic perovskite materials for the application of sensors and light-emitting diodes(LEDs) fields.

关键词： Lead-free Heterometallic Perovskite Phase transition Photoluminescence

X-site doping in ABX_(3) triggers phase transition and higher T_(c) of the dielectric switch in perovskite

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Chinese Chemical Letters 2021年第11期32卷 3558-3561页

作者： Youya Yu Peizhi Huang Yuzhen Wang Zhixu Zhang Tie Zhang Yi Zhang dawei fu Ordered Matter Science Research Centerjiangsu Key Laboratory for Science andApplications of Molecular Ferroelectrics Southeast UniversityNanjing 211189China Institute for Science and Applications of Molecular Ferroelectrics Key Laboratory of the Ministry of Education for Advanced Catalysis MaterialsZhejiang Normal UniversityJinhua 321004China

Material stability is always the key factor for applied materials especially the working environment that requires higher temperature sensitivity or temperature fluctuation *** which,the stimulus-response perovskite materials are just sensitive to stability to ensure the accuracy and stability of the signals,in the applied devices of batteries and memory storage devices and so ***,it is still a tremendous challenge to improve the stability of perovskite materials,and maintain reliability in the ***,a novel ABX_(2)X'_(1)(X-site doping in an ABX_(3))compound[CEMP]-[CdBr_(2)(SCN)](1,CEMP=1-(2-chloro-ethyl)-1-methyl-piperidine)with remarkable high-temperature reversible dielectric switching behavior was *** strategy of[SCN]^(−)doping in perovskite for improving the stability was successfully ***,the steric hindrance is increased while the energy barrier is also increased by replacing hydrogen with flexible groups,which leads to a high-temperature reversible phase *** new finding provides a new direction to enrich new applications and design ideas of perovskite *** the X-site strategy of doping or substitution in the ABX_(3),it will promote ingenious and perfect experimental results in material synthesis and performance improvement by chemistry disciplines.

关键词： Dielectric switch X-site doping High-temperature Phase transition Molecule design

Construction, photoelectric response and phase transition for new hybrid double perovskites showing narrow band gaps

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Chinese Chemical Letters 2023年第4期34卷 595-600页

作者： Changyuan Su Zhixu Zhang Jie Yao Ming Chen Peizhi Huang Yi Zhang dawei fu Liyan Xie Ordered Matter Science Research Center Jiangsu Key Laboratory for Science and Applications of Molecular FerroelectricsSoutheast UniversityNanjing 211189China Institute for Science and Applications of Molecular Ferroelectrics Key Laboratory of the Ministry of Education for Advanced Catalysis MaterialsZhejiang Normal UniversityJinhua 321004China Chaotic Matter Science Research Center Department of MaterialsMetallurgy and ChemistryJiangxi University of Science and TechnologyGanzhou 341000China

To explore the lead-free key scientific issue in perovskite, double perovskite based on Ag Bi and Cu Bi was naturally selected as a competitive candidate due to its fascinating functional features, such as self-powered circularly polarized light detection, X-ray detection, photoluminescence and so on. However, the most challenging point is to simulate the structure and function of traditional lead-based perovskite in new double perovskite. At the same time, there are few suitable double perovskite systems with optical and electrical potential. The above two points greatly limit the competitiveness of double perovskite. In order to solve this problem, firstly, by analyzing and comparing previous studies,we used 2,2-dimethylpropan-1-aminium(abbreviated as 2,2-DPA) as the organic template to assemble materials. Solid-to-solid phase transition materials(2,2-DPA)3Bi2I91 and(2,2-DPA)3Pb2I72 were constructed. Along the path of lead-free and two-dimensional maintenance, we successfully synthesized(2,2-DPA)4AgBiI8.H_(2)O 3 and(2,2-DPA)_(4)CuBiI8.H_(2)O 4. As two typical semiconductors, 3 and 4 with narrower optical band gaps of 1.98 and 1.76 e V show obvious photo-response when the xenon lamp with intensity of 20 m W/cm^(2)is on or off, implying that they may be applied to light-harvesting and light-detecting devices. By referring to the phase transition mechanism of 1 and 2, 3 may be caused by ordered-disordered transition of the organic part, which was proven to be the first solid-to-solid phase transition material with -oriented layered double perovskites with n = 1 by systematic characterization methods after dehydration for all we know. We believed that this work can provide meaningful guidance for the development of lead-free double perovskites.

关键词： Double perovskite Photoelectric response Phase transition Dielectric properties Semiconducting behavior

Macro-micro behaviors and failure mechanism of frozen weakly cemented mudstone

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1337-1347页

作者： Xianzhou Lyu Jijie Du Hao fu dawei Lyu Weiming Wang College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao266590China College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao266590China

Understanding the mechanical properties and multiscale failure mechanism of frozen soft rock is an important prerequisite for the construction safety of tunnels,artificially frozen ground and other infrastructure in cold *** this study,the triaxial compression test are performed on mudstone in the weakly cemented soft rock strata in the mining area of western China,and the mechanical characteristics and failure mechanism of weakly cemented mudstone are systematically investigated under the combined action of freezing and ***,the quantitative relationship between the microstructural parameters and the macroscopic strength and deformation parameters is established based on fractal ***,the failure mechanism of frozen weakly cemented mudstone is revealed on both micro- and *** results show that temperature and confining pressure significantly affects the elastic modulus and peak strength of weakly cemented *** decreasing temperature,the compressive strength increases,while the corresponding peak strain decreases *** the deformation curve,the plastic deformation stage is shortened,and the brittle fracture feature at the post-peak stage is more prominent,and the elastic modulus correspondingly increases with decreasing *** low-temperature conditions,most of the weakly cemented mudstone undergoes microscopic shear failure along the main fracture *** micro-fracture morphology characteristics of weakly cemented mudstone under different temperatures are quantified via the fractal dimension,and an approximately exponential relationship can be obtained among the fractal dimension and the temperature,compressive strength and elastic modulus.

关键词： Weakly cemented mudstone Artificial freezing Mechanical properties Linkage destruction mechanism Fractal dimension

珠三坳陷文昌B凹陷古近系文昌组——恩平组古气候特征

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矿产勘查 2024年第6期15卷 946-955页

作者：马大钧程斌付大巍陈丽君孟祥雨刘华中国石油大学(华东)深层油气全国重点实验室山东青岛266580 中海石油(中国)有限公司湛江分公司广东湛江266510

古气候对有机质的生产和保存具有重要的作用,对烃源岩的发育至关重要,而温暖湿润的古气候条件通常被认为有利于优质烃源岩的形成。古近系文昌组及恩平组是珠三坳陷文昌B凹陷内最重要的烃源岩发育层段,恢复其沉积时期的古气候对凹陷内烃... 详细信息

古气候对有机质的生产和保存具有重要的作用,对烃源岩的发育至关重要,而温暖湿润的古气候条件通常被认为有利于优质烃源岩的形成。古近系文昌组及恩平组是珠三坳陷文昌B凹陷内最重要的烃源岩发育层段,恢复其沉积时期的古气候对凹陷内烃源岩优选有着至关重要的作用。本文选取文昌B凹陷WB-1、WB-2井泥、页岩样品,通过分析孢粉组合与主微量元素数据以得到沉积时期的古气候特征。孢粉组合特征表明凹陷内文昌组—恩平组烃源岩沉积时期气候整体为热—亚热带,湿润—半湿润;主微量元素证据中,古气候敏感性元素Sr/Cu及CIA指标进一步证实了这一时期气候温暖湿润的特性,特别是Mn/Mg及Rb/Sr比值强调了文二段沉积时期气候条件最为温暖湿润。因此,文二段沉积时期被认为是文昌B凹陷优质烃源岩发展的最佳时期。

关键词：珠三坳陷文昌B凹陷古近纪古气候优质烃源岩

Developing an atmospheric aging evaluation model of acrylic coatings:A semi-supervised machine learning algorithm

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1617-1627页

作者： Yiran Li Zhongheng fu Xiangyang Yu Zhihui Jin Haiyan Gong Lingwei Ma Xiaogang Li dawei Zhang Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China National Materials Corrosion and Protection Data Center University of Science and Technology BeijingBeijing 100083China BRI Southeast Asia Network for Corrosion and Protection(MOE) Shunde Innovation School of University of Science and Technology BeijingFoshan 528399China

To study the atmospheric aging of acrylic coatings,a two-year aging exposure experiment was conducted in 13 representative climatic environments in *** atmospheric aging evaluation model of acrylic coatings was developed based on aging data including11 environmental factors from 567 cities.A hybrid method of random forest and Spearman correlation analysis was used to reduce the redundancy and multicollinearity of the data set by dimensionality reduction.A semi-supervised collaborative trained regression model was developed with the environmental factors as input and the low-frequency impedance modulus values of the electrochemical impedance spectra of acrylic coatings in 3.5wt%NaCl solution as *** model improves accuracy compared to supervised learning algorithms model(support vector machines model).The model provides a new method for the rapid evaluation of the aging performance of acrylic coatings,and may also serve as a reference to evaluate the aging performance of other organic coatings.

关键词： acrylic coatings coatings aging atmospheric environment machine learning

Tissue adhesive,ROS scavenging and injectable PRP-based‘plasticine’for promoting cartilage repair

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Regenerative Biomaterials 2024年第1期3卷 94-107页

作者： Shiao Li dawei Niu Haowei Fang Yancheng Chen Jinyan Li Kunxi Zhang Jingbo Yin Peiliang fu Department of Orthopedics Shanghai Changzheng HospitalNaval Medical UniversityShanghai 200003P.R.China Department of Polymer Materials School of Materials Science and EngineeringShanghai UniversityShanghai 200444P.R.China

Platelet-rich plasma(PRP)that has various growth factors has been used clinically in cartilage ***,the short residence time and release time at the injury site limit its therapeutic *** present study fabricated a granular hydrogel that was assembled from gelatin microspheres and tannic acid through their abundant hydrogen *** microspheres with the gelatin concentration of 10wt%and the diameter distribution of 1-10 lm were used to assemble by tannic acid to form the granular hydrogel,which exhibited elasticity under low shear strain,but flowability under higher shear *** viscosity decreased with the increase in shear ***,the granular hydrogel exhibited self-healing feature during rheology ***,granular hydrogel carrying PRP not only exhibited well-performed injectability but also performed like a‘plasticine’that possessed good *** granular hydrogel showed tissue adhesion ability and reactive oxygen species scavenging *** hydrogel carrying PRP transplanted to full-thickness articular cartilage defects could integrate well with native cartilage,resulting in newly formed cartilage articular fully filled in defects and well-integrated with the native cartilage and subchondral *** unique features of the present granular hydrogel,including injectability,plasticity,porous structure,tissue adhesion and reactive oxygen species scavenging provided an ideal PRP carrier toward cartilage tissue engineering.

关键词： cartilage regeneration granular hydrogel gelatin tannic acid PRP