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A Machine-Learning Approach for the Prediction of Fly-Ash Concrete Strength

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Fluid Dynamics & Materials Processing 2023年第12期19卷 3007-3019页

作者： Shanqing Shao Aimin Gong ran Wang Xiaoshuang Chen Jing Xu fulai Wang Feipeng Liu College of Water Conservancy Yunnan Agricultural UniversityKunming650201China Institute of International Rivers and Eco-Security Yunnan UniversityKunming650500China Southwest Survey and Planning Institute of National Forestry and Grassland Administration Kunming650031China

The composite exciter and the CaO to Na_(2)SO_(4) dosing ratios are known to have a strong impact on the mechanical strength offly-ash *** the present study a hybrid approach relying on experiments and a machine-learn-ing technique has been used to tackle this *** tests have shown that the optimal admixture of CaO and Na_(2)SO_(4) alone is 8%.The best 3D mechanical strength offly-ash concrete is achieved at 8%of the compound activator;If the 28-day mechanical strength is considered,then,the best performances are obtained at 4%of the compound ***,the 3D mechanical strength offly-ash concrete is better when the dosing ratio of CaO to Na_(2)SO_(4) in the compound activator is 1:1;the maximum strength offly-ash concrete at 28-day can be achieved for a 1:1 ratio of CaO to Na_(2)SO_(4) by considering a 4%compound *** this case,the compressive andflexural strengths are 260 MPa and 53.6 MPa,respectively;the mechanical strength offly-ash concrete at 28-day can be improved by a 4:1 ratio of CaO to Na_(2)SO_(4) by considering 8%and 12%compound *** is shown that the predictions based on the aforementioned machine-learning approach are accurate and reliable.

关键词： Fly ash compound activator machine-learning approach

Microscopic Analysis of Cementitious Sand and Gravel Damming Materia

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Fluid Dynamics & Materials Processing 2024年第4期20卷 749-769页

作者： ran Wang Aimin Gong Shanqing Shao Baoli Qu Jing Xu fulai Wang Feipeng Liu College of Water Conservancy Yunnan Agricultural UniversityKunming650201China Tianqi Engineering Consulting Co. Ltd.Kunming650000China Institute of International Rivers and Ecological Security Yunnan UniversityKunming650500China

The mechanical properties of cementitious sand and gravel damming material have been experimentally determined by means of microscopic SEM(Scanning Electron Microscopy)image *** results show that the combination of fly ash and water can fill the voids in cemented sand and gravel test blocks because of the presence of hydrated calcium silicate and other substances;thereby,the compactness and mechanical properties of these materials can be greatly *** every 10 kg/m^(3) increase in the amount of cementitious material,the density increases by about 2%,and the water content decreases by 0.2%.The amount of cementitious material used in the sand and gravel in these tests was 80-110 kg/m^(3),the water-binder ratio was ***,the splitting tensile strength was 1/10 of the compressive strength,and the maximum strength was 7.42 MPa at 90 *** optimal mix ratio has been found to be 50 kg of cement,60 kg of fly ash and 120 kg of water(C50F60W120).The related dry density was 2.6 g/cm^(3),the water content was 6%,and the water-binder ratio was 1.09.

关键词： Cementitious sand gravel material scanning electron microscopy optimal mix ratio maximum strength

Palladium/Copper Cocatalyzed Coupling Reaction of Aroyl Hydrazides with Indoles

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Chinese Journal of Chemistry 2016年第12期34卷 1213-1217页

作者： Congrong Liu fulai Yang School of Environment Engineering Nanjing Institute of Technology Jiangsu Nanjing 211167 China Department of Chemistry University of Science and Technology of China Hefei Anhui 230026 China

An unprecedented palladium/copper cocatalyzed coupling reaction of indoles with simple aroyl hydrazides has been developed under aerobic conditions. A range of aroyl hydrazides underwent palladium/copper cocatalyzed oxidative arylation with indoles open to air in a 1：1 mixture of dimethyl sulfoxide and nitromethane to give structurally diverse 2-arylindoles or 3-arylindoles in moderate to good yields. The reaction well tolerates a wide variety of functional groups such as alkoxy, halo, ester.

关键词： aroyl hydrazides coupling reaction indole palladium catalyst copper catalyst

Ultrathin layered double hydroxide nanosheets prepared by original precursor method for photoelectrochemical photodetectors

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Nano Research 2022年第10期15卷 9392-9401页

作者： Yu Wang fulai Zhao Yiyu Feng Wei Feng School of Materials Science and Engineering Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Composite and Functional Materials Tianjin 300072China Key Laboratory of Advanced Ceramics and Machining Technology Ministry of EducationTianjin 300350China Key Laboratory of Materials Processing and Mold Ministry of EducationZhengzhou UniversityZhengzhou 450002China

Layered double hydroxides(LDHs)are widely used owing to their unique alternating anionic and cationic layered twodimensional(2D)***,studies on the preparation of 2D LDH nanosheets with uniform thickness and their photodetectors are *** this study,two novel ultrathin LDH(Ca-In and Ca-Al LDH)nanosheets are peeled off from precursor bimetallic phosphides through the original precursor *** Ca-In and Ca-Al LDH nanosheets demonstrate a uniform thickness distribution with an average thickness of 3–4 nm,micron-level lateral sizes,and moderate *** to its broad light absorption range,hydrophilicity,and stability,Ca-In and Ca-Al LDH nanosheets are applied for the first time in photoelectrochemical photodetectors,realizing a wide range of light detection from ultraviolet(365 nm)to visible light(635 nm).Moreover,the fabricated photodetectors exhibit excellent cycle stability,and the average photocurrent density shows no reduction after 70 ***,this study provides an effective method to prepare 2D Ca-In and Ca-Al LDH nanosheets with uniform thickness and photoelectric application prospects.

关键词： layered double hydroxides precursor method thickness photoelectrochemical photodetectors calculations

Mineral inclusions in zircon domains and geological significance of SHRIMP U-Pb dating for coesite-bearing zircons of paragneiss in Sulu terrane, eastern China

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Science China Earth Sciences 2005年第2期48卷 175-184页

作者： LIU fulai YANG Jingsui XU Zhiqin Institute of Geology Chinese Academy of Geological SciencesBeijing100037China Institute of GeologyChinese Academy of Geological SciencesBeijing100037China Institute of GeologyChinese Academy of Geological SciencesBeijing100037China

Laser Raman spectroscopy and cathodoluminescence (CL) image reveal that zircons separated from paragneisses in the southwestern Sulu terrane (eastern China) preserve multi-stage mineral assemblages in different zircon domains. In the same paragneiss zircon sample, some zircon grains retain inherited (detrital) cores with abundant low-pressure mineral inclusions of Qtz + Phe + Ap + impurities and Qtz + Phe + impurities. The ultrahigh-pressure (UHP) metamorphic overgrowths mantles of these zircons preserve Coe, Coe + Phe and other UHP mineral inclusions, indicating that these inherited (detrital) zircons from protoliths experienced metamorphic recrystallization during the Sulu UHP metamorphic event. However, other zircon grains preserve UHP mineral inclusions of Coe, Coe + Ap and Coe + Phe in the cores and mantles, whereas the outmost rims contain quartz (Qtz) and other low-pressure mineral inclusions. These phenomena prove that the second group zircons were crystallized at UHP metamorphic stage and overprinted by the late retrogressive metamorphism related to the Sulu terrane exhumation. SHRIMP U-Pb dating reveals that zircons separated from the paragneisses recorded complicated geochronological traces. Some zircons retain inherited cores with the 206Pb/238U ages of 284-754 Ma, indicating the complexity of the detrital zircons in protoliths. Coesite-bearing zircon domains recorded 238-266 Ma (with the average age of 245(14 Ma) for the UHP metamorphic event. The retrogressive rims of zircons recorded 213-223 Ma (with the average age of 217(15 Ma) for the late-stage amphibolite facies metamorphic event, indicating that the rapid exhumation time for the Sulu UHP terrane is about 220 Ma.

关键词： Sulu terrane, paragneiss, zircon, mineral inclusion, cathodoluminescence, SHRIMP U-Pb dating.

The progressive onset and evolution of Precambrian subduction and plate tectonics

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Science China Earth Sciences 2020年第12期63卷 2068-2086页

作者： Xiaolei Wang fulai Liu Junyong Li Di Wang State Key laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing210023China Institute of Geology Chinese Academy of Geological SciencesBeijing100037China

The regime of plate tectonics on early Earth is one of the fundamental problems in Earth *** era takes the majority(ca.88%)of Earth’s history and thus plays a key role in understanding the onset of plate tectonics and the mechanism,distribution and process of Precambrian subduction *** paper presents a review on the progresses of subduction and subduction zones in different stages of Precambrian era,and sorts out some key issues and fields that merits further *** suggest that there was progressive onset and evolution of subduction and plate tectonics from Archean to Proterozoic *** emphasize the importance of comprehensive studies on subduction mechanism,metamorphic type,plate tectonics regime,the compositional evolution of continental crust,and petrogenesis of diverse granitoids formed in the *** is proposed that innovative analytical techniques,big data,experimental petrology and numerical geodynamic modeling will facilitate future studies of Precambrian subduction zones.

关键词： Precambrian Subduction Plate tectonics Continent formation Progressive evolu

An Efficient Prins Cyclization for Stereoselective Synthesis of Tetrahydropyran from Imines and Homoallyl Alcohols

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Chinese Journal of Chemistry 2014年第11期32卷 1095-1098页

作者： Congrong Liu Daojuan Cheng fulai Yang School of Environment Engineering Nanjing Institute of TechnologyNanjingJiangsu 211167China Joint Laboratory of Green Synthetic Chemistry Department of ChemistryUniversity of Science and Technology of ChinaHefeiAnhui 230026China

An unprecedented protocol has been developed for the efficient synthesis of substituted tetrahydropyrans via a bismuth-promoted Prins cyclization of imines with homoallyl *** the presence of 40 mol%BiCl_(3),a wide variety of imines react smoothly with homoallyl alcohols at room temperature to give the corresponding 4-chlorotetrahydropyran derivatives in good to excellent yields.

关键词： Prins cyclization tetrahydropyrans imine homoallyl alcohol Lewis acid

Depositional Age, Provenance Characteristics and Tectonic Setting of the Ailaoshan Group in the Southwestern South China Block

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Acta Geologica Sinica(English Edition) 2019年第6期93卷 1687-1710页

作者： JI Lei LIU fulai WANG Fang TIAN Zhonghua Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Beijing 100037China

The depositional and metamorphic ages and provenances of the Ailaoshan(ALS) Group in the Ailaoshan-Red River(ALS-RR) shear zone, southwestern South China Block(SCB), were investigated to constrain the tectonic history of the southwestern SCB. In this study, we use petrology, geochemical analysis, zircon cathodoluminescence imaging and UPb geochronology to analyse samples of quartzite, garnet-bearing two-mica schist and metapelite. The age spectra of detrital zircon grains from these metasediments show two dominant age peaks at 550–424 Ma and 876–730 Ma and two subordinate peaks at 970–955 Ma and ~2450 Ma. The youngest peak, corresponding to the early Palaeozoic, accounts for more than 20% of the total dates and constrains the deposition of the ALS Group to the Palaeozoic rather than the Palaeoproterozoic as traditionally thought. Moreover, two peaks of metamorphic ages corresponding to the Permo-Triassic and Cenozoic were also identified, and these ages document the tectonothermal events associated with the Indosinian collision between the Indochina Block and the SCB and the Himalayan collision between the Indian and Asian plates. Geochemical data suggest that the provenances of the ALS Group were dominated by continental arc and recycled metasedimentary rocks. The comparison of probability density distribution plots of the detrital zircon U-Pb age data indicates that the Neoproterozoic detritus in the ALS Group was probably derived from the arc-related Neoproterozoic intrusive bodies in the northwestern and southwestern SCB. Furthermore, the early Palaeozoic detritus might have been sourced from eroded early Palaeozoic strata and magmatic plutons in Cathaysia and volcanic rocks in the western Indochina Block.

关键词： detrital zircon depositional age provenance Ailaoshan Group South China Block

Germanium-based monoelemental and binary two-dimensional materials:Theoretical and experimental investigations and promising applications

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InfoMat 2022年第11期4卷 1-82页

作者： fulai Zhao Yiyu Feng Wei Feng School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjinPeople's Republic of China Key Laboratory of Advanced Ceramics and Machining Technology Ministry of EducationTianjinPeople's Republic of China Collaborative Innovation Center of Chemical Science and Engineering TianjinPeoples Republic of China

Two-dimensional(2D)materials based on group IVA elements have attracted extensive attention owing to their rich chemical structures and novel *** comprehensive review focuses on the phases of Ge monoelemental and binary 2D materials including germanene and its derivatives,Ge-IVA binary compounds,Ge-VA binary compounds,and Ge-VIA binary *** latest progress in predictive modeling,fabrication,and fundamental and physical property modulation of their stable 2D configurations are ***,various interesting applications of these Ge-based 2D materials are discussed,particularly field effect transistors,photodetectors,optical devices,catalysts,energy storage devices,solar cells,thermoelectric devices,sensors,biomedical materials,and spintronic ***,this review con-cludes with a few perspectives and an outlook for quickly expanding the appli-cation scope Ge-based 2D materials based on recent developments.

关键词： 2D materials binarycompounds electronicproperties germanene groupIVAelements