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Data-driven mapping-relationship mining between hardness and mechanical properties of dual-phase titanium alloys via random forest and statistical analysis

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Rare Metals 2024年第2期43卷 829-841页

作者： Hai-Chao Gong Qun-Bo Fan Hong-mei zhang Xing-Wang Cheng Wen-Qiang Xie Kai Chen Lin Yang Jun-Jie zhang Bing-Qiang Wei Shun Xu School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China National Key Laboratory of Science and Technology on Materials Under Shock and Impact Beijing100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing401135China Department of Mechanical and Materials Engineering University of Nebraska-LincolnLincolnNE68588USA

In order to accelerate the research on the property optimization of titanium alloy based on high-throughput methods,it is necessary to reveal the relationship between hardness and other mechanical properties which is still *** this work,taking Ti2.C alloy as research object,almost all the microstructure of dual-phase titanium alloys were covered by traversing over 100 heat treatment ***,massive experiments including microstructure characterization and performance test were conducted,obtaining 51,590 pieces of microstructure data and 3591 pieces of mechanical property ***,based on large-scale data-driven technology,the quantitative mapping relationship between hardness and other mechanical properties was deeply *** results of random forest models showed that the correlation between hardness(H)and Charpy impact energy(A_(k))(or elongation,A)was hardly dependent on the microstructure types,while the relationship between H and tensile strength(R_(m))(or yield strength,R_(p0.2.)was highly dependent on microstructure ***,combined with statistical analysis,it was found that the relationship between H and Ak(or A)were negatively ***,the relationship between H and strength was positively linear for equiaxed microstructure,and strength was linked to d^(−1/2.(d,equivalent circle diameter)ofα-grains in the form of classical Hall–Petch formula;but for other microstructures,the relationships were ***,the above rules were nearly the same in the rolling direction and transverse ***,a"four-quadrant partition map"between H and R_(p0.2./R_(m) was established as a versatile material-screening tool,which can provide guidance for on-demand selection of titanium alloys.

关键词： Dual-phase titanium alloy Data-driven Hardness Mapping relationship

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Non-linear relationship between age and subfoveal choroidal thickness in Chinese patients with proliferative diabetic retinopathy

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World Journal of Diabetes 2024年第9期15卷 1903-1915页

作者： Chun-Yan Lei Jiang-Ying Xie Qi-Bo Ran mei-Xia zhang Department of Ophthalmology and Research Laboratory of Macular Disease West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Sichuan University Operating Room Department of AnesthesiologyWest China HospitalSichuan University/West China School of NursingSichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND No study has investigated the change regularity between age and subfoveal choroidal thickness(SFCT)in proliferative diabetic retinopathy(PDR).AIM To investigate the relationship between the SFCT and age in Chinese patients with *** This was a cross-sectional retrospective *** participants were hospitalized individuals with type 2.diabetes who underwent vitrectomy for *** eyes that met the criteria were included in the *** necessary laboratory tests were performed at the time of *** macular thickness(CMT)and SFCT were two quantitative assessments made using enhanced depth imaging optical coherence *** was measured automatically and SFCT was measured manually with digital calipers provided by the Heidelberg Eye Explorer *** The final analysis included a total of 2.4 individuals with *** average age was 55.60 years old±10.03 years old,and 57.69%of the population was *** analysis revealed a significant negative connection between age and SFCT in patients with PDR[β=-2.44,95%confidence interval(95%CI):-3.46 to-1.42.P2.97 to-0.39;P=0.0117).Spline smoothing showed that the relationship between SFCT and age in patients with PDR was non-linear,with an inflection point at 54 years of *** Our findings suggest that age is a key determinant of choroidal *** non-linear link between SFCT and age in PDR patients should be taken into account.

关键词： Age Subfoveal choroidal thickness Proliferative diabetic retinopathy Optical coherence tomography Central macular thickness

Better use of experience from other reservoirs for accurate production forecasting by learn-to-learn method

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Petroleum Science 2024年第1期21卷 716-728页

作者： Hao-Chen Wang Kai zhang Nancy Chen Wen-Sheng Zhou Chen Liu Ji-Fu Wang Li-Ming zhang Zhi-Gang Yu Shi-Ti Cui {2.-Chun Yang China University of Petroleum(East China) 66 Changjiang West RoadQingdao West Coast New AreaQingdao266580ShandongChina University of Calgary 2500 University Dr NWCalgaryT2N 1N4AlbertaCanada Qingdao University of Technology Qingdao266071ShandongChina State Key Laboratory of Offshore Oil Exploitation Beijing100028China CNOOC Research Institute Ltd. Beijing100028China CNPC Tarim Oilfield Branch Company Korla841000XinjiangChina National Engineering Laboratory for Exploration and Development of Low-Permeability Oil and Gas Fields Xi'an710000ShaanxiChina Sinopec Matrix Co. LTDQingdao266000ShandongChina

To assess whether a development strategy will be profitable enough,production forecasting is a crucial and difficult step in the *** development history of other reservoirs in the same class tends to be studied to make predictions ***,the permeability field,well patterns,and development regime must all be similar for two reservoirs to be considered in the same *** results in very few available experiences from other reservoirs even though there is a lot of historical information on numerous reservoirs because it is difficult to find such similar *** paper proposes a learn-to-learn method,which can better utilize a vast amount of historical data from various ***,the proposed method first learns how to learn samples before directly learning rules in ***,by utilizing gradients from networks with independent parameters and copied structure in each class of reservoirs,the proposed network obtains the optimal shared initial parameters which are regarded as transferable information across different *** on that,the network is able to predict future production indices for the target reservoir by only training with very limited samples collected from reservoirs in the same *** cases further demonstrate its superiority in accuracy to other widely-used network methods.

关键词： Production forecasting Multiple patterns Few-shot learning Transfer learning

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Inherently Chiral and Symmetrical Heteroatom-Doped Zigzag-Type Hydrocarbon Belts

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CCS Chemistry 2024年第5期6卷 1198-1210页

作者： Xue-Yuan Wang Xin-Yu zhang Shuo Tong Qing-Hui Guo mei-Ling Tan Cheng-Jun Li mei-Xiang Wang Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084

hydrocarbon belts due to their potential applications in carbon *** contrast,heteroatomembedded zigzag hydrocarbon belts as advanced design strategies with fascinating structures and desirable,unique properties have remained largely unexplored,and inherently chiral ones are ***,we report the synthesis of a diversity of symmetric and highly enantiopure inherently chiral O-and N-doped zigzag-type hydrocarbon belts starting from strainless macrocycles based on fjord-stitching *** readily available pertriflated resorcin[6]arene underwent partial hydrolyses and intramolecular S_(N)Ar reactions to form a calix[3](9H-xanthene)derivative and a prochiral half-belt *** transformations of calix[3](9H-xanthene)into C_(3v)-symmetric molecular belts were achieved by closing the rest of the fjords with triple intramolecular S_(N)Ar reactions and Yamamoto homo coupling reactions,as well as palladiumcatalyzed intermolecular acridination reactions with primary *** prochiral half-belt underwent enantioselective desymmetrizative mono-acridination to afford an inherently chiral N,O_(4)-bridged pseudo-belt with an enantiomeric excess(ee)value of>99%under the catalysis of Pd(OAc)_(2.and(R)-*** closure reactions of the pseudo-belt produced diverse heteroatom-inlayed zigzag-type hydrocarbon belts of inherent ***,we showed the unique cavity structures of the belts and demonstrated interesting chiroptic properties of the inherently enantiopure chiral *** research opens the door for the exploration of novel and sophisticated symmetric and inherently chiral molecular nanobelt structures with outstanding physical and chemical properties,as well as potential applications.

关键词： zigzag-type molecular belt heterocycle chiroptical property fjord-stitching strategy resorcinarene

Leakage Proof,Flame-Retardant,and Electromagnetic Shield Wood Morphology Genetic Composite Phase Change Materials for Solar Thermal Energy Harvesting

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Nano-Micro Letters 2024年第10期16卷 99-120页

作者： Yuhui Chen Yang Meng Jiangyu zhang Yuhui Xie Hua Guo Mukun He Xuetao Shi Yi mei Xinxin Sheng Delong Xie Yunnan Provincial Key Laboratory of Energy Saving in Phosphorus Chemical Engineering and New Phosphorus Materials The International Joint Laboratory for Sustainable Polymers of Yunnan ProvinceThe Higher Educational Key Laboratory for Phosphorus Chemical Engineering of Yunnan ProvinceFaculty of Chemical EngineeringKunming University of Science and TechnologyKunming 650500People's Republic of China Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter School of Materials and EnergyGuangdong University of TechnologyGuangzhou 510006People's Republic of China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi'anShaanxi 710072People's Republic of China

Phase change materials(PCMs)offer a promising solution to address the challenges posed by intermittency and fluctuations in solar thermal ***,for organic solid-liquid PCMs,issues such as leakage,low thermal conductivity,lack of efficient solar-thermal media,and flamma-bility have constrained their broad ***,we present an innova-tive class of versatile composite phase change materials(CPCMs)developed through a facile and environmentally friendly synthesis approach,leveraging the inherent anisotropy and unidirectional porosity of wood aerogel(nanowood)to support polyethylene glycol(PEG).The wood modification process involves the incorporation of phytic acid(PA)and MXene hybrid structure through an evaporation-induced assembly method,which could impart non-leaking PEG filling while concurrently facilitating thermal conduction,light absorption,and ***,the as-prepared wood-based CPCMs showcase enhanced thermal conductivity(0.82.W m^(-1)K^(-1),about 4.6 times than PEG)as well as high latent heat of 135.5 kJ kg^(-1)(91.5%encapsula-tion)with thermal durability and stability throughout at least 2.0 heating and cooling cycles,featuring dramatic solar-thermal conversion efficiency up to 98.58%.In addition,with the synergistic effect of phytic acid and MXene,the flame-retardant performance of the CPCMs has been significantly enhanced,showing a self-extinguishing ***,the excellent electromagnetic shielding of 44.45 dB was endowed to the CPCMs,relieving contemporary health hazards associated with electromagnetic ***,we capitalize on the exquisite wood cell structure with unidirectional transport inherent in the development of multifunctional CPCMs,showcasing the operational principle through a proof-of-concept prototype system.

关键词： Wood PCMs MXene Solar thermal storage and conversion Flame-retardant Electromagnetic shielding

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Colloidal quantum dot for infrared-absorbing solar cells:State-oftheart and prospects

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Nano Research Energy 2024年第1期3卷 172-219页

作者： Siyu Zheng Xinyi mei Jingxuan Chen Erik MJJohansson Xiaoliang zhang School of Materials Science and Engineering Beihang UniversityBeijing 100191China Department of Chemistry-Ångström Physical ChemistryUppsala UniversityUppsala 75120Sweden

Colloidal quantum dot(CQD)shows great potential for application in infrared solar cells due to the simple synthesis techniques,tunable infrared absorption spectrum,and high stability and *** to significant efforts made on the surface chemistry of CQDs,device structure optimization,and device physics of CQD solar cells(CQDSCs),remarkable breakthroughs are achieved to boost the infrared photovoltaic performance and stability of *** particular,the CQDSC with a high power conversion efficiency of~14%and good stability is reported,which is very promising for infrared-absorbing solar *** this review,we highlight the unique optoelectronic properties of CQDs for the development of infrared-absorbing solar ***,the latest advances in finely controlling surface properties of CQDs are comprehensively summarized and ***,the device operation of CQDSCs is discussed in-depth to highlight the impact of the device structure optimization of CQDSCs on their photovoltaic performance,and the emerging novel types of CQDSCs,such as semitransparent,flexible,and lightweight CQDSCs,are also *** device stability of CQDSCs is also highlighted from the viewpoint of practical ***,the conclusions and possible challenges and opportunities are presented to promote the development steps of the CQDSCs with higher infrared photovoltaic performance and robust stability.

关键词： colloidal quantum dot solar cell photovoltaic performance infrared absorbing solar energy

Large Deviations for a Critical Galton-Watson Branching Process

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Acta Mathematicae Applicatae Sinica 2024年

作者： Dou-dou LI Wan-lin SHI mei zhang College of Statistics and Data Science Faculty of Science Beijing University of Technology Laboratory of Mathematics and Complex Systems (Ministry of Education) School of Mathematical SciencesBeijing Normal University Department of Mathematics and Physics North China Electric Power University

In this paper, a critical Galton-Watson branching process{Zn}is considered. Large deviation rates of SZn:=∑i=1ZnXiare obtained, where{Xi, i≥1}is a sequence of independent and identically distributed random variables and X1is in the domain of attraction of an α-stable law with α∈(0, 2.. One shall see that the convergence rate is determined by the tail index of X1and the variance of Z1. Our results can be compared with those ones of the supercritical case.

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Metal-Free Electrochemical Trifluoromethylation of Imidazole-Fused Heterocycles with Trifluoromethyl Thianthrenium Triflate

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Chinese Journal of Chemistry 2024年第15期42卷 1679-1685页

作者： Chang Ge Lipeng Qiao Yuyang zhang Kai Sun jangzhen An mei Peng Xiaolan Chen Lingbo Qu Bing Yu College of Chemistry Zhengzhou UniversityZhengzhouHenan 450001China National Engineering Research Center of Low-Carbon Processing and Utilization of Forest Biomass Nanjing Forestry UniversityNanjingJiangsu210037China School of Pharmacy Hengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China

A novel and eco-friendly electrochemical activation of trifluoromethyl thianthrenium triflate(TT-CF_(3)^(+)OTf^(-))for trifluoromethylation of imidazole-fused heteroaromatic compounds was *** method involves the direct electrolysis of TT-CF_(3)^(+)OTf^(-)without the requirement of external oxidants or catalysts,aligning with the principles of green chemistry.A wide range of imidazole-fused heteroaromatic compounds including imidazo[1,2.a]pyridines and benzo[d]imidazo[2.1-b]thiazoles have been successfully trifluoromethylated using this technique,exhibiting excellent compatibility with various functional groups and a broad substrate ***,the method's applicability for one-pot sequential reactions enables the reduction of waste and resource consumption by eliminating the need for intermediate purification steps.

关键词： Trifluoromethylation Electrochemical Metal-free Imidazole-fused heterocycles Thianthrenium

O_(2. adsorption on Fe_(3)O_(4) (110) surface and effect of gangue element Al doping: combined study of binding experiment and ab initio molecular dynamics

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Journal of Iron and Steel Research International 2024年第4期31卷 810-827页

作者： Zheng-jian Liu Hui-qing Jiang Yao-zu Wang Jian-liang zhang Hong-mei Qiao An-yang Zheng Fang-yu Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing 100083China Beijing Shougang Co. Ltd.Qian'an 064404HebeiChina Department of Physics National University of Defense TechnologyChangsha 410128HunanChina

At high temperature,the chemical reaction mechanism at the interface of magnetite and the influence mechanism of gangue element Al on the oxidation performance of magnetite are not *** addition,due to the limitation of existing experimental equipment,it is difficult to clarify the interface reaction mechanism in the oxidation process and the influence mechanism of Al on the surface oxidation reaction of Fe_(3)O_(4) at an atomic scale at high *** surface oxidation reaction mechanism of magnetite and the influence mechanism of Al on the oxidation of magnetite were studied by experiments and AIMD(ab initio molecular dynamics).The experimental results show that the existence of Al_(2.O_(3) will reduce the initial oxidation temperature and comprehensive oxidation performance of *** AIMD results show that aluminum can accelerate the interface reaction rate of Fe_(3)O_(4) in the high-temperature oxidation atmosphere,but the strong Al-O binding ability is not conducive to the transfer of O atoms in the oxidation process.

关键词： Ironmaking Magnetite oxidation Interface reaction Adsorption-Gangue aluminum AIMD