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Centrifuge study on behavior of raft foundation after tunnelling in soft clay

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Underground Space 2024年第4期17卷 161-169页

作者： Jian Yu Jiaming Liu Chun Fai Leung Maosong Huang qi wen Jorgin Tan Department of Geotechnical Engineering Key Laboratory of Geotechnical and Underground Engineering of Ministry of EducationTongji UniversityShanghai 200092China Centre for Offshore Research and Engineering Department of Civil and Environmental EngineeringNational University of Singapore119077Singapore Land Transport Authority 219428Singapore

Ground losses due to tunneling would induce settlement of nearby raft *** study the change in behavior of the raft foundations over time due to tunnel excavation in soft clay,a series of centrifuge model tests were *** results reveal that the raft stiffness has a significant influence on the development of the gap between the raft and the *** width of the gap beneath the flexible foundation would increase over time,leading to a further increase in tensile strain after excavation,whereas the gap for raft foundations with a large stiffness would reduce with time,causing a gradual decrease in tensile *** modification factor(MF)design approach is also evaluated with the test results and demonstrates that the MF design approach would underestimate the tensile strain of the flexible raft and provide a relatively conservative prediction for larger stiffnesses.

关键词： Tunnelling Raft Clay Deflection ratio Centrifuge test

Realizing the excellent oxidation resistance of an environmental barrier coating through aluminum surface modification

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Journal of Advanced Ceramics 2024年第7期13卷 976-986页

作者： Lin Dong wen-qi Yang Lin Chen Guan-Jun Yang Chang-Jiu Li State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Xi’an Aerospace Engine Company Limited in China Aerospace Science and Technology Corporation Xi’an 710065China

The lifetime of Si-based environmental barrier coatings(EBCs)is constrained by thermally grown SiO_(2)oxidelayer(SiO_(2)-TGO),which can cause premature cracking and *** address this issue,a new approach for surfacemodification using aluminum is *** oxidation performance was examined in a 50 vol%H_(2)O-50 vol%O_(2)environment at 1350℃for up to 300 *** results indicate that a dense ytterbium aluminum garnet(YbAG)layer wasformed after modification,decreasing the porosity by 80%.Due to the elimination of fast diffusion channels and the lowoxygen permeability of YbAG,aluminum modification significantly reduced the growth rate of SiO_(2)-TGO by nearly twoorders of ***,its thickness decreased by more than 70%after 300 h of exposure.A diffusioncontrolled oxidation mechanism indicates that the modified dense surface is equivalent to an initial SiO_(2)layer with a specificthickness,causing a shift in the oxidation time and increasing the oxidation *** research provides valuableinsights for designing Si-based EBC with improved lifetimes.

关键词： environmental barrier coating(EBC) oxidation modification diffusion cracking

Durable dual-state duplex Si-HfO_(2)with excellent oxidation and cracking resistance

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Journal of Advanced Ceramics 2024年第3期13卷 388-401页

作者： Lin Chen Jing-Chuan Luo wen-qi Yang Chang-Jiu Li Guan-Jun Yang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Xi’an Aerospace Engine Company Limited in CASC Xi’an 710065China

The lifetime of Si bond coatings in environmental barrier coatings is constrained by phase-transition-induced cracking of the SiO_(2)*** this study,Si-HfO_(2)dual-state duplex composite materials are proposed to address this issue by partially forming HfSiO_(4)and minimizing the SiO_(2)*** as-prepared composite exhibited a structure comprising discrete HfO_(2)“bricks”embedded in a continuous Si“mortar”,while the oxidized state transformed into discrete HfSiO_(4)“bricks”within continuous thin SiO_(2)“mortars”.The results indicate that continuous thin SiO_(2)contributes to reducing the oxidation rate to a level comparable to that of pure Si,and discrete HfSiO_(4)particles aid in relieving phase transition-induced stress and inhibiting crack propagation,thereby enhancing oxidation and cracking resistance ***,the composite with 20 mol%HfO_(2)and a mean particle size of~500 nm at 1370℃exhibited a service lifetime 10 times greater than that of pure *** research provides valuable insights for designing Si-based bond coatings with improved service lifetime.

关键词： oxidation environmental barrier coatings(EBCs) phase transition cracking bond coatings

Intrinsically asymmetric atomic character regulates piezoelectricity in two-dimensional materials

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Frontiers of physics 2024年第3期19卷 153-162页

作者： Yun-qin Li qi-wen He Dai-Song Tang Xiao Shang Xiao-Chun Wang School of Physics Science and Information Technology Liaocheng UniversityLiaocheng 252000China Key Laboratory of Polar Materials and Devices Ministry of EducationDepartment of ElectronicsEast China Normal UniversityShanghai 200241China Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China

Decreasing of layer thickness causes the decrease of polarization until it disappears due to the existence of depolarization ***,the search for strong piezoelectric materials is highly desirable for multifunctional ultra-thin piezoelectric ***,we propose a common strategy for achieving strong piezoelectric materials through the electronic asymmetry induced by the intrinsically asymmetric atomic character of different chalcogen ***,in the tetrahedral lattice structures,for example,M4X3Y3(M=Pd/Ni,X/Y=S,Se or Te,X≠Y)monolayers are proved to display excellent out-of-plane ***4Se3Te3 possesses the largest piezoelectric coefficient d33 of 61.57 pm/V,which is much larger than that of most 2D *** the electronic asymmetry further increases the out-of-plane piezoelectricity of Janus M4X3Y3 ***,the out-of-plane piezoelectricity is positively correlated with the ratio of electronegativity difference(Red)and the electric dipole moment(P).This work provides alternative materials for energy harvesting nano-devices or self-energized wearable devices,and supplies a valuable guideline for predicting 2D materials with strong out-of-plane piezoelectricity.

关键词： piezoelectricity intrinsically asymmetric atomic character ratio of electronegativity difference electric dipole moment first-principles calculations

Automated machine learning for rainfall-induced landslide hazard mapping in Luhe County of Guangdong Province,China

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China Geology 2024年第2期7卷 315-329页

作者： Tao Li Chen-chen Xie Chong Xu wen-wen qi Yuan-dong Huang Lei Li National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China Key Laboratory of Compound and Chained Natural Hazards Dynamics Ministry of Emergency Management of ChinaBeijing 100085China Institute of Disaster Prevention Sanhe 065201China School of Emergency Management Science and Engineering University of Chinese Academy of SciencesBeijing 100049China

Landslide hazard mapping is essential for regional landslide hazard *** main objective of this study is to construct a rainfall-induced landslide hazard map of Luhe County,China based on an automated machine learning framework(AutoGluon).A total of 2241 landslides were identified from satellite images before and after the rainfall event,and 10 impact factors including elevation,slope,aspect,normalized difference vegetation index(NDVI),topographic wetness index(TWI),lithology,land cover,distance to roads,distance to rivers,and rainfall were selected as *** WeightedEnsemble model,which is an ensemble of 13 basic machine learning models weighted together,was used to output the landslide hazard assessment *** results indicate that landslides mainly occurred in the central part of the study area,especially in Hetian and *** 102.44 s were spent to train all the models,and the ensemble model WeightedEnsemble has an Area Under the Curve(AUC)value of92.36%in the test *** addition,14.95%of the study area was determined to be at very high hazard,with a landslide density of 12.02 per square *** study serves as a significant reference for the prevention and mitigation of geological hazards and land use planning in Luhe County.

关键词： Landslide hazard Heavy rainfall Harzard mapping Hazard assessment Automated machine learning Shallow landslide Visual interpretation Luhe County Geological hazards survey engineering

Effects of Heterologously Overexpressing PIP5K-Family Genes in Arabidopsis on Inflorescence Development

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Phyton-International Journal of Experimental Botany 2024年第1期93卷 97-117页

作者： Mingda Yin Rui Luo Tana Liang qi wen Xiaotian Liang Yanpeng wen Xuemei Hu Zhiyan Wang Chang Gao wenjing Ren Fenglan Huang College of Life Science and Food Engineering Inner Mongolia Minzu UniversityTongliao028000China Key Laboratory of Castor Breeding of the State Ethnic Affairs Commission Inner Mongolia Minzu UniversityTongliao028000China Inner Mongolia Industrial Engineering Research Center of Universities for Castor Inner Mongolia Minzu UniversityTongliao028043China Inner Mongolia Key Laboratory of Castor Breeding and Comprehensive Utilization Inner Mongolia Minzu UniversityTongliao028000China Inner Mongolia Engineering Research Center of Industrial Technology Innovation of Castor Inner Mongolia Minzu UniversityTongliao028000China

Castor is one of the top 10 oil crops in the world and has extremely valuable *** inflorescences directly affect yield,so the study of inflorescence development is very important in increasing castor *** previous studies have shown that the PIP5K gene family(PIP5Ks)is associated with inflorescence *** this study,to determine the function of each PIP5K gene in castor,a female Lm-type castor line,aLmAB2,was used to determine the relative expression levels of the PIP5Ks in castor *** PIP5K genes were heterologously overexpressed in Arabidopsis thaliana,the relative expression of each gene and the effect on plants was determined in ***,and the relationships among the PIP5Ks in castor were *** expression levels of the PIP5Ks in the female Lm-type castor line aLmAB2 were *** relative expression levels of the PIP5K9 and PIP5K11 genes were high(p<0.05)in isofemale inflorescences,and those of PIP5K1,PIP5K2,PIP5K6,and PIP5K8 were high(p<0.05)in female inflorescences but low(p<0.05)in bisexual *** PIP5Ks were heterologously overexpressed in ***,and T3-generation plants with stable genetic resistance,i.e.,AT-PIP5K^(+)plants(AT-PIP5K1^(+),AT-PIP5K2^(+),AT-PIP5K6^(+),AT-PIP5K8^(+),AT-PIP5K9^(+),and ATPIP5K11^(+) plants),were *** tests of the AT-PIP5K+plants showed that the growth of the main stem was significantly delayed in AT-PIP5K+plants compared with Columbia wild-type(WT)*** plants;the PIP5K1 and PIP5K2 genes promoted lateral stem growth and flower and silique development;and the PIP5K6,PIP5K8,PIP5K9 and PIP5K11 genes inhibited lateral stem growth and flower and silique *** correlations among PIP5Ks in castor suggest that there may be a synergistic relationship among PIP5K1,PIP5K2,and PIP5K6 in castor inflorescences,and PIP5K8,PIP5K9,and PIP5K11 are complementary to the other three genes.

关键词： Castor inflorescence development PIP5K gene family gene overexpression

Establishing Modular Cell-Free Expression System for the Biosynthesis of Bicyclomycin from a Chemically Synthesized Cyclodipeptide

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Chinese Journal of Chemistry 2024年第4期42卷 384-390页

作者： Yi-Pei Liu Yu-Heng Zhao wen-qi Zhang Lian Wu Linjuan Huang Gong-Li Tang Jun-Bin He Shaanxi Natural Carbohydrate Resource Engineering Research Center College of Food Science and TechnologyNorthwest UniversityXi'anShaanxi710069 China State Key Laboratory of Chemical Biology Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of Sciences(CAS)CASShanghai200032 China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of CAS1 Sub-lane XiangshanHangzhouZhejiang310024 China

Cell-free expression systems have emerged as a versatile and powerful platform for metabolic engineering,biosynthesis and synthetic biology ***,successful examples of the synthesis of complex natural products using this system are still ***,a structurally unique and complex diketopiperazine alkaloid,is a clinically promising antibiotic that selectively inhibits the transcription termination factor ***,we established a modular cell-free expression system with cascade catalysis for the biosynthesis of bicyclomycin from a chemically synthesized *** six cell-free expressed biosynthetic enzymes,including five iron-andα-ketoglutarate-dependent dioxygenases and one cytochrome P450 monooxygenase,were active in converting their substrates to the corresponding *** co-expressed enzymes in the cell-free module were able to complete the related partial *** vitro biosynthesis of bicyclomycin was also achieved by reconstituting the entire biosynthetic pathways(i.e.,six enzymes)using the modular cell-free expression *** study demonstrates that the modular cell-free expression system can be used as a robust and promising platformforthe biosynthesis of complex antibiotics.

关键词： Natural products Bicyclomycin Biosynthesis Iron-andα-ketoglutarate-dependent dioxygenases Cytochrome P450 monooxygenase Cell-freeprotein synthesis Enzyme catalysis

Photoexcitation of Dihydroquinazolinone Anionic Compounds:Difluoroalkylarylation and Difluoroalkylamination of Alkenes

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CCS Chemistry 2024年第10期6卷 2549-2559页

作者： Jian-Xiong Yang Jia-qing Hu qi wen Jie Xu Yan Zhang Heng Jiang School of Chemistry and Chemical Engineering Chemistry and Biomedicine Innovation Center(Chem BIC)Nanjing UniversityNanjing 210023 Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Shanghai Frontiers Science Center of Drug Target Identification and DeliverySchool of Pharmaceutical SciencesShanghai Jiao Tong UniversityShanghai 200240

The direct excitation of dihydroquinazolinone(DHQ)anions by visible light has been demonstrated by photophysical *** excited-state DHQ anion serves as both a potent reductant and a radical precursor in a redox neutral radical cascade,circumventing the use of an external photoredox *** gem-difluoroalkyl radicals(CF_(2)H and CF_(2)R)are produced from the excited-state DHQ anions,leading to the first example of intermolecular 1,2-difluoroalkylarylation(CF_(2)H-and CF_(2)R-arylation)of alkenes in overall redox-neutral ***,1,2-difluoroalkylamination of styrenes has also been realized,offering a practical pathway for the preparation of diverseβ-CF_(2)H *** general and efficient strategy for the generation of CF_(2)H and CF_(2)R radicals exhibits great potential for applications in drug discovery.

关键词： excited state anion difluoromethyl radical difluoromethylation photochemistry radical chemistry

Application of texture signatures based on multiparameter-magnetic resonance imaging for predicting microvascular invasion in hepatocellular carcinoma:Retrospective study

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1309-1318页

作者： Hai-Yang Nong Yong-Yi Cen Mi qin wen-qi qin You-Xiang Xie Lin Li Man-Rong Liu Ke Ding Department of Radiology The Third Affiliated Hospital of Guangxi Medical UniversityNanning 530031Guangxi Zhuang Autonomous RegionChina Department of Radiology The Affiliated Hospital of Youjiang Medical University for NationalitiesBaise 533000Guangxi Zhuang Autonomous RegionChina Department of Radiology The First Affiliated Hospital of Guangxi University of Traditional Chinese MedicineNanning 530031Guangxi Zhuang Autonomous RegionChina Department of Hepatobiliary Surgery The Third Affiliated Hospital of Guangxi Medical UniversityNanning 530031Guangxi Zhuang Autonomous RegionChina Department of Ultrasound The Third Affiliated Hospital of Guangxi Medical UniversityNanning 530031Guangxi Zhuang Autonomous RegionChina

BACKGROUND Despite continuous changes in treatment methods,the survival rate for advanced hepatocellular carcinoma(HCC)patients remains low,highlighting the importance of diagnostic methods for *** To explore the efficacy of texture analysis based on multi-parametric magnetic resonance(MR)imaging(MRI)in predicting microvascular invasion(MVI)in preoperative *** This study included 105 patients with pathologically confirmed HCC,categorized into MVI-positive and MVI-negative *** employed Original Data Analysis,Principal Component Analysis,Linear Discriminant Analysis(LDA),and Non-LDA(NDA)for texture analysis using multi-parametric MR images to predict preoperative *** effectiveness of texture analysis was determined using the B11 program of the MaZda4.6 software,with results expressed as the misjudgment rate(MCR).RESULTS Texture analysis using multi-parametric MRI,particularly the MI+PA+F dimensionality reduction method combined with NDA discrimination,demonstrated the most effective prediction of MVI in *** accuracy in the pulse and equilibrium phases was 83.81%.MCRs for the combination of T2-weighted imaging(T2WI),arterial phase,portal venous phase,and equilibrium phase were 22.86%,16.19%,20.95%,and 20.95%,*** area under the curve for predicting MVI positivity was 0.844,with a sensitivity of 77.19%and specificity of 91.67%.CONCLUSION Texture analysis of arterial phase images demonstrated superior predictive efficacy for MVI in HCC compared to T2WI,portal venous,and equilibrium *** study provides an objective,non-invasive method for preoperative prediction of MVI,offering a theoretical foundation for the selection of clinical therapy.

关键词： Magnetic resonance imaging Hepatocellular carcinoma Texture analysis Microvascular invasion