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Multi-source data integration and multi-scale modeling framework for progressive prediction of complex geological interfaces in tunneling

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Underground Space 2024年第2期15卷 1-25页

作者： Jingxiao Wang Peinan Li xiaoying Zhuang xiaojun Li xi jiang Jun Wu Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China College of Environmental Science and Engineering Donghua UniversityShanghai 201620China Institute of Photonics Department of Mathematics and PhysicsLeibniz University HannoverHannover 30167Germany Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 100872China College of Civil Engineering Shanghai Normal UniversityShanghai 200233China

A reliable geological model plays a fundamental role in the efficiency and safety of mountain tunnel ***,regional models based on limited survey data represent macroscopic geological environments but not detailed internal geological characteristics,especially at tunnel portals with complex geological *** paper presents a comprehensive methodological framework for refined modeling of the tunnel surrounding rock and subsequent mechanics analysis,with a particular focus on natural space distortion of hard-soft rock interfaces at tunnel *** progressive prediction of geological structures is developed considering multi-source data derived from the tunnel survey and excavation *** improve the accuracy of the models,a novel modeling method is proposed to integrate multi-source and multi-scale data based on data extraction and potential field ***,a regional-scale model and an engineering-scale model are built,providing a clear insight into geological phenomena and supporting numerical *** addition,the proposed framework is applied to a case study,the Long-tou mountain tunnel project in Guangzhou,China,where the dominant rock type is *** results show that the data integration and modeling methods effectively improve model structure *** improved model’s calculation deviation is reduced by about 10%to 20%in the mechanical *** study contributes to revealing the complex geological environment with singular interfaces and promoting the safety and performance of mountain tunneling.

关键词： Mountain tunnel Geological modeling Multi-source data Progressive prediction Tunnel portals

Preparation of High-Strength Al–Mg–Si/Al_2O_3 Composites with Lamellar Structures Using Freeze Casting and Pressureless Infiltration Techniques

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Acta Metallurgica Sinica(English Letters) 2014年第5期27卷 944-950页

作者： Ping Shen Juwei xi Yujie Fu Alateng Shaga Chang Sun Qichuan jiang Key Laboratory of Automobile Materials (Ministry of Education) Department of Materials Science and EngineeringJilin University

Lamellar porous alumina scaffolds with the initial solid loadings of 20, 25, and 30 vol% were prepared by freeze casting using 5 μm alumina powders. With the addition of 3 wt% MgO-A1203-SiO2 nanopowders in a eutectic composition as sintering aid, the maximum compressive strength of the sintered scaffolds reached （64 -4- 2） MPa after sintering at 1,773 K for 2 h. The lamellar porous scaffolds were then filled with a molten Al-12Si-10 Mg alloy （in wt%） by pressureless infiltration at 1,223 K in a N2 atmosphere, yielding the shell-like structure of the composites. The compressive strength of the upper part composite with the initial 30 vol% solid loading reached （1,190 ±50） MPa, which was about 3.5 times as large as that of the matrix alloy.

关键词： Biomimetic Metal-matrix composites Porous materials

Synchrotron radiation-based materials characterization techniques shed light on molten salt reactor alloys

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Nuclear Science and Techniques 2020年第1期31卷 57-71页

作者： Li jiang xiang-xi Ye De-Jun Wang Zhi-Jun Li Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Ministry of Ecology and Environment Beijing 100135China

From a safety point of view, it is important to study the damages and reliability of molten salt reactor structural alloy materials, which are subjected to extreme environments due to neutron irradiation, molten salt corrosion, fission product attacks, thermal stress, and even combinations of these. In the past few years, synchrotron radiation-based materials characterization techniques have proven to be effective in revealing the microstructural evolution and failure mechanisms of the alloys under surrogating operation conditions. Here, we review the recent progress in the investigations of molten salt corrosion,tellurium(Te) corrosion, and alloy design. The valence states and distribution of chromium(Cr) atoms, and the diffusion and local atomic structure of Te atoms near the surface of corroded alloys have been investigated using synchrotron radiation techniques, which considerably deepen the understandings on the molten salt and Te corrosion behaviors. Furthermore, the structure and size distribution of the second phases in the alloys have been obtained, which are helpful for the future development of new alloy materials.

关键词： Molten salt reactor Alloy materials Synchrotron radiation Shanghai Synchrotron Radiation Facility Molten salt corrosion Tellurium corrosion

Partial P-Type Metal Ions Doping Induced Variation of Both Crystal Structure and Oxygen Vacancy Within Cu/SnO_(2) Metastable Solid Solution Nanofibers for Highly Sensitive C_(2)H_(2) Sensor

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Chemical Research in Chinese Universities 2021年第3期37卷 584-588页

作者： WANG Ruifang YU xi LI Zhenyu CHEN Jingyu jiang Tingting State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500P.R.China Center of Functional Materials for Working Fluids of Oil and Gas Field School of New Energy and MaterialsSouthwest Petroleum UniversityChengdu610500P.R.China School of Engineering Southwest Petroleum UniversityNanchong637001P.R.China School of Chemical Engineering Northeast Electric Power UniversityJilin132012P.R.China

Partial P-type metal ions doping(PPMID)is an alternative method to further enhance the gas sensing performance of N-type metal oxides(NMOs)in contrast to that of P-N metal oxides heterojunctions,but the influences of the introduction of PPMID on the grain size and oxygen vacancies of NMOs have been rarely ***,a simple and effective route has been demonstrated to address this problem with Cu^(2+)-doped SnO_(2) metastable solid solution nanofibers(CSMSSNs)as model and C_(2)H_(2) as target molecule by combining electrospinning and calcination *** seems that the introduction of PPMID can also affect crystal structure and oxygen vacancies of NMOs,proven by combining X-ray diffraction(XRD)and X-ray photoelectron spectra(XPS).Thus,PPD,crystal structure and oxygen vacancies have been combined to clarify the enhanced sensing performance of Cu-doped SnO_(2) metastable solid solution nanofibers angainst C_(2)H_(2).

关键词： P-Type doping P-N heterojunction Electrospinning Metastable solid solution nanofiber C_(2)H_(2)sensor

Machine learning accelerated DFT research on platinum-modified amorphous alloy surface catalysts

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Chinese Chemical Letters 2023年第5期34卷 645-649页

作者： xi Zhang Kangpu Li Bo Wen jiang Ma Dongfeng Diao Institute of Nanosurface Science and Engineering Guangdong Provincial Key Laboratory of Micro/NanoShenzhen UniversityShenzhen 518060China College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060China Research Center of Medical Plasma Technology Shenzhen UniversityShenzhen 518060China

Pt-modified amorphous alloy(Pt@PdNiCuP)catalyst exhibits excellent electro-catalytic activity and high experimental durability for hydrogen evolution reaction(HER).However,the physical origin of the catalytically active remains *** this paper,we constructed a distance contribution descriptor(DCD)for the feature engineering of machine learning(ML)potential,and calculated the Gibbs free energies(ΔGH)of 46,000*H binding sites on the Pt@Pd Ni Cu P surface by ML-accelerated density functional theory(DFT).The relationship betweenΔGHand DCD revealed that in the H-Pt distance region of 2.0-2.5 A where the parabolic tail and disordered scatters coexist,the H-metal bonding configuration is mainly the bridge-or hollow-bonding *** contribution analysis of DCD indicates that the joint effect of Pt,Pd and Ni atoms determines the catalytical behavior of amorphous alloy,which agrees well with experimental *** counting atomic percentages in different energy intervals,we obtained the atomic ratio for the best catalytic performance(Pt:Pd:Ni:Cu:P=0.33:0.17:0.155:0.16:0.185).Projected density of states(PDOS)show that H 1s orbital,Pt 5d orbital,and Pd 4d orbital form a bonding state at-2 e *** results provide new ideas for designing more active amorphous alloy catalysts.

关键词： Hydrogen evolution reaction Amorphous alloy Density functional theory Machine learning

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Chinese Physics Letters 2011年第5期28卷 184-186页

作者： HE Yong HU xi-Wei jiang Zhong-He Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 621900 College of Electrical and Electronic Engineering Huazhong University of Science and TechnologyWuhan 430074

Instability of a planar shock front perturbed by a corrugated interface is analyzed,where the perturbation wavelength is along the shock front *** presented analysis involves the effects of the features on the shock front,which is different from a general method presented by D'yakov and Kontorovich,where the shock front is taken as an infinitely *** growth rate of the instability of the perturbed shock front is obtained and compared with the growth rate of the Rayleigh-Taylor instability(RTI)of an interface,on which the density gradient and the initial conditions are similar to the perturbed shock *** analysis and comparisons of the growth rate of the instability indicate that the features of the shock front should be considered seriously in the shock interface interactions.

关键词： shock perturbed interface

Intercellular mitochondrial transfer as a means of revitalizing injured glomerular endothelial cells

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World Journal of Stem Cells 2022年第9期14卷 729-743页

作者： Li-xia Tang Bing Wei Lu-Yao jiang You-You Ying Ke Li Tian-xi Chen Ruo-Fei Huang miao-Jun Shi Hang Xu Department of Endocrinology The First People’s Hospital of Yongkang Affiliated to Hangzhou Medical CollegeJinhua 321300Zhejiang ProvinceChina School of Medicine Southeast UniversityNanjing 210009Jiangsu ProvinceChina Department of Medical Rehabilitation The First People’s Hospital of Yongkang Affiliated to Hangzhou Medical CollegeJinhua 321300Zhejiang ProvinceChina Department of Nephrology The First People’s Hospital of Yongkang Affiliated to Hangzhou Medical CollegeJinhua 321300Zhejiang ProvinceChina Department of Hemodialysis/Nephrology The First People’s Hospital of Yongkang Affiliated to Hangzhou Medical CollegeJinhua 321300Zhejiang ProvinceChina

BACKGROUND Recent studies have demonstrated that mesenchymal stem cells(MSCs)can rescue injured target cells via mitochondrial ***,it has not been fully understood how bone marrow-derived MSCs repair glomeruli in diabetic kidney disease(DKD).AIM To explore the mitochondrial transfer involved in the rescue of injured glomerular endothelial cells(GECs)by MSCs,both in vitro and in *** In vitro experiments were performed to investigate the effect of co-culture with MSCs on high glucose-induced *** transfer of mitochondria was visualized using fluorescent *** were freshly sorted and ultimately tested for apoptosis,viability,mRNA expression by real-time reverse transcriptase-polymerase chain reaction,protein expression by western blot,and mitochondrial ***,streptozotocin-induced DKD rats were infused with MSCs,and renal function and oxidative stress were detected with an automatic biochemical analyzer and related-detection kits after 2 *** histology was analyzed by hematoxylin and eosin,periodic acid-Schiff,and immunohistochemical *** Fluorescence imaging confirmed that MSCs transferred mitochondria to injured GECs when cocultured in *** found that the apoptosis,proliferation,and mitochondrial function of injured GECs were improved following ***,MSCs decreased pro-inflammatory cytokines[interleukin(IL)-6,IL-1β,and tumor necrosis factor-α]and pro-apoptotic factors(caspase 3 and Bax).Mitochondrial transfer also enhanced the expression of superoxide dismutase 2,B cell lymphoma-2,glutathione peroxidase(GPx)3,and mitofusin 2 and inhibited reactive oxygen species(ROS)and dynamin-related protein 1 ***,MSCs significantly ameliorated functional parameters(blood urea nitrogen and serum creatinine)and decreased the production of malondialdehyde,advanced glycation end products,and ROS,whereas they increased the levels of GPx and superoxide dismutase in *** addition,

关键词： Mitochondria transfer Mesenchymal ste

A New Class of Amide Ligands Enable Cu-Catalyzed Coupling of Sodium Methanesulfinate with （Hetero）aryl Chlorides

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Chinese Journal of Chemistry 2017年第11期35卷 1661-1664页

作者： Dawei Ma Songtao Niu Jinlong Zhao xi jiang Yongwen jiang xiaojing Zhang Tiemin Sun State Key Laboratory of Bioorganic and Natural Products Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences 345 Lingling Lu Shanghai 200032 China Shenyang Pharmaceutical University 103 Wenhua Lu Shenyang 110016 China

（（2S,4R）-4-Hydroxy-N-（2-methylnaphthalen-l-yl）pyrrolidine-2-carboxamide （HMNPC）, an amide derived from 4-hydroxy-L-proline and 2-methyl naphthalen-l-amine, is a powerful ligand for Cu-catalyzed coupling of （het- ero）aryl halides with sulfinic acid salts, allowing for first time the metal-catalyzed coupling of （hetero）aryl chlorides and NaSO2Me. A considerable number of （hetero）aryl chlorides worked well, providing the pharmaceutically im- portant （hetero）aryl methylsulfones in good to excellent yields.

关键词： (hetero)aryl methylsulfone coupling reaction (hetero)aryl halides ligand copper

^(31)P NMR Study on Some Phosphorus-Containing Compounds

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Chinese Chemical Letters 2000年第12期11卷 1057-1060页

作者： Zhen XU Ji Liang SHI xin CHEN xi Kui jiang Shanghai Institute of Organic Chemistry Chinese Academy of Sciences354 Fenglin RoadShanghai 200032

31P NMR has become a widely applied spectroscopic probe of the structure of phosphorus-containing compounds. Meanwhile, the application of 31P NMR has been rapidly expanded to biochemistry and medicinal chemistry of phosphorus-containing compounds because the growing importance of the phosphorus compounds is now widely realized. We report here the results of 31P NMR study on some phosphorus-containing compounds, namely, O-alkyl O-4-nitrophenyl methyl phosphonates with different alkyl chain-length (MePO-n), 4-nitrophenyl alkylphenylphosphinates with different alkyl chain-length (PhP-n), diethyl phosphono- acetonitrile anion and diethyl phosphite anion . Our results indicate that 31P NMR can not only be applied to not only the study of the hydrolytic reactions of MePO-8 and PhP-8 but also be applied to the study of the presence of the anions of diethylphosphonoacetonitrile and diethyl phosphite in nucleophilic reactions.

关键词： 31P NMR phosphorus-containing compounds nucleophilic reaction.