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Petroleum Science 2021年第5期18卷 1305-1322页

作者： ji-yuan wang Shao-Bin Guo School of Energy Resources China University of GeosciencesBeijing100083China Key Laboratory of Strategy Evaluation for Shale Gas Ministry of Land and ResourcesBeijing100083China

The relationship between hydrocarbon generation and the evolution of shale pore structure and its heterogeneity of continental shale from the Ordos Basin,China was quantitatively studied based on thermal simulation experiment,mercury injection capillary pressure(MICP),gas adsorption,vitrinite reflectance(R_(o))analysis,and hydrocarbon generation test combined with Frenkel-Halsey-Hill(FHH)fractal *** result shows that the pore volume(PV)and specific surface area(SSA)of pores with different pore sizes show a trend of decreasing first and then increasing as the maturity increases in general,R_(o)>1.59%is initially defined as a favorable stage for pore development in continental *** generation has different effects on pore heterogeneity of different *** the N_(2)adsorption,the roughness of small pore surface(D_(1))decreases in the oil window;the complexity of large pore structure(D_(2))increases in the oil window but decreases in the gas *** the MICP,the heterogeneity of small pore(D_(1))increases in the oil window and increases first and then decreases in the gas window;D_(2)remains basically constant during the whole stage and is close to 3,indicating that the heterogeneity of large pores is extremely strong and is not affected by hydrocarbon generation.

关键词： Shale Hydrocarbon generation Pore evolution Fractal dimension

Novel, Green, Simple and Uncatalyzed Route for High Yield Preparation of Benzaldehyde Glycol Acetal

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Chemical Research in Chinese Universities 2011年第5期27卷 799-802页

作者： TANG jia SONG ji-yuan wang Ge YANG Mu GUO Wan-chun School of Material Science and Engineering University of Science and Technology Beijing Beij＇ing 100083 P. R. China

A simple approach for the condensation of benzaldehyde with ethylene glycol was adopted without employing any catalyst. The study reveals that factors including temperature, molar ratio of reactants, and the water removal significantly influence the conversion ratio of benzaldehyde. The results indicate that the use of optimal reaction conditions such as temperature and water removing exhibits more pronounced effects on the conversion ratio of benzaldehyde compared with the use of catalysts. In a word, a green and simple method for the condensation of aldehyde and menthandiol has been devised and investigated.

关键词： Condensation Benzaldehyde Ethylene glycol

Comparison of irradiation-induced void formations in tungsten with equiaxed and columnar structures

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Tungsten 2024年第4期6卷 794-805页

作者： Liu Xi jia-Jun Zhao ji-Jun Zhao yuan-yuan wang Key Laboratory of Materials Modification by Laser Ion and Electron Beams(Ministry of Education) Dalian University of Technology

Tungsten(W) has been received much attention,since it is regarded as one of the most promising plasma facing materials for fusion *** are two typical morphologies of unirradiated polycrystalline W,which have the equiaxed and columnar grains,***,the role of arrangement of grain boundary(GB) in absorbing irradiation-generated point defects is still waiting to be *** current investigation,irradiation-induced void formations in W with equiaxed and columnar microstructures are predicted,respectively,using the developed phase-field *** significant kinetic behavior,such as the generation and annihilation of point defects and the interaction between point defects and GB,is reasonably *** density,size and porosity of void formed in these two microstructures are examined and analyzed according to the effects of GB ratio,temperature and damage *** analytical results show that higher GB ratio can effectively reduce void porosity,and the columnar-grained structure has better irradiation resistance than that of the equiaxed one in the case of small grain *** importantly,the predicted void sizes changed with temperature and damage rate agree well with the experimentally measured *** work has a more beneficial contribution to the microstructural improvement of International Thermonuclear Experimental Reactor-grade W.

关键词： Grain morphology Irradiation-induced void Phase-field Tungsten

Structural features in the mid-southern section of the Kyushu–Palau Ridge based on satellite altimetry gravity anomaly

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Acta Oceanologica Sinica 2024年第4期43卷 50-60页

作者： Feifei Zhang Dingding wang Xiaolin ji Fanghui Hou yuan Yang Wanyin wang School of Geological Engineering and Geomatics Chang’an UniversityXi’an 710054China Qingdao Institute of Marine Geology China Geological SurveyQingdao 266071China Information and Navigation College Air Force Engineering UniversityXi’an 710077China National Engineering Research Center of Offshore Oil and Gas Exploration Beijing 100028China Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China

The Kyushu–Palau Ridge(KPR),an anti-S-shaped submarine highland at the center of the Philippine Sea Plate(PSP),is considered the residual arc of the Izu–Bonin–Mariana Island Arc,which retains key information about the cessation of the Western Philippine Basin(WPB)expansion and the Parece Vela Basin(PVB)***,using the new generation of satellite altimetry gravity data,high-precision seafloor topography data,and newly acquired ship-borne gravity data,the topographic and gravity characteristics of the KPR mid-southern section and adjacent region are *** distribution characteristics of the faults were delineated using the normalized vertical derivative–total horizontal derivative method(NVDR-THDR)and the minimum curvature potential field separation *** Moho depth and crustal thickness were inverted using the rapid inversion method for a double-interface model with depth *** on these results,the crust structure features in the KPR mid-southern section,and the“triangular”structure geological significance where the KPR and Central Basin Rift(CBR)of the WPB intersect are *** KPR crustal thickness is approximately 6–16 km,with a distinct discontinuity that is slightly thicker than the normal oceanic *** KPR mid-southern section crust structure was divided into four segments(S1–S4)from north to south,formed by the CBR eastward extension joint action and clockwise rotation of the PVB expansion axis and the Mindanao fault zone blocking effect.

关键词： structural features satellite altimetry gravity data Kyushu-Palau Ridge Central Basin Rift faults Moho depth

Pyrolysis Empirical Modeling of Polyester Glass Fiber Reinforced Plastics Using Sestak-Berggren Model Method

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Journal of Thermal Science 2024年第2期33卷 725-738页

作者： NAN Wei ji Wenhui yuan Yanping yuan Zhongyuan SUN Yong School of Mechanical Engineering Southwest Jiaotong UniversityChengdu610031China CRRC Changchun Railway Vehicles Co. LtdChangchun130062China

Polyester Glass Fiber Reinforced Plastic(Polyester GFRP),a thermosetting plastic comprised of glass fiber and polyester polymer compounds,is extensively utilized in high-speed *** its pyrolysis mechanism is crucial as it significantly influences the combustion characteristics and fire safety ***,kinetic research on polyester GFRP primarily focuses on employing the Coats-Redfern method to derive a theoretical kinetic ***,the pyrolysis process of polyester GFRP is complex and the aforementioned theoretical model fails to accurately describe the pyrolysis ***,this study seeks to utilize the Sestak and Berggren(SB) model as a methodological approach to reveal the complex reaction mechanism during the pyrolysis *** on thermogravimetric analysis,the entire pyrolysis process of polyester GFRP is divided into two primary ***,model-free methods are employed to ascertain the activation energy and pre-exponential *** results show that the fitted empirical models of the two main pyrolysis stages are f(α)=(1-α)^(1.47)[-ln(1-α)]^(1.50) and f(α)=(1-α)^(1.77)[-ln(1-α)]^(1.72),*** predicted results are in good agreement with experimental data under different heating rates,which indicates that the empirical model can sufficiently describe the pyrolysis process of polyester GFRP.

关键词： polyester GFRP model-fitting methods empirical models pyrolysis

Light People: Professor Fanglin Bao and his cover story

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Light(Science & Applications) 2024年第6期13卷 1015-1020页

作者： ji wang School of Science Westlake UniversityHangzhouZhejiangPR China

Qu yuan,a renowned ancient Chinese poet,once pondered in his work Heavenly Inquiry:“If the sun’s light is absent,from where does the radiance of the Hero Flower emanate?”The ability to see clearly in the darkest of nights has long been a sought-after magical power by *** holds not only immense technological significance for computer vision and remote sensing but also profound implications for transcending the dichotomy between day and night in our daily *** Fanglin Bao from Westlake University has made significant breakthroughs in this field,bringing us closer to a world where we can transform night into *** groundbreaking research on Heat-Assisted Detection and Ranging(HADAR)and night vision was featured as the cover story in Nature on July 26,2023.

关键词： bringing breakthrough holds

Data-driven casting defect prediction model for sand casting based on random forest classification algorithm

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China Foundry 2024年第2期21卷 137-146页

作者： Bang Guan Dong-hong wang Da Shu Shou-qin Zhu Xiao-yuan ji Bao-de Sun Shanghai Key Lab of Advanced High-Temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Lab of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China Hefei Casting and Forging Factory of Anhui Heli Co. LtdHefei 230000China State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan 430074China

The complex sand-casting process combined with the interactions between process parameters makes it difficult to control the casting quality,resulting in a high scrap rate.A strategy based on a data-driven model was proposed to reduce casting defects and improve production efficiency,which includes the random forest(RF)classification model,the feature importance analysis,and the process parameters optimization with Monte Carlo *** collected data includes four types of defects and corresponding process parameters were used to construct the RF *** results show a recall rate above 90% for all *** Gini Index was used to assess the importance of the process parameters in the formation of various defects in the RF ***,the classification model was applied to different production conditions for quality *** the case of process parameters optimization for gas porosity defects,this model serves as an experimental process in the Monte Carlo method to estimate a better temperature *** prediction model,when applied to the factory,greatly improved the efficiency of defect *** show that the scrap rate decreased from 10.16% to 6.68%.

关键词： sand casting process data-driven method classification model quality prediction feature importance

Artemordins A-S, Cadinane-Type Sesquiterpenoid Dimers from Artemisia ordosica and Their Antihepatoma Activities

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Chinese Journal of Chemistry 2024年第13期42卷 1493-1508页

作者： yuan wang Tian-Ze Li Yun-Bao Ma Chang-An Geng Yong-Cui wang ji-Jun Chen State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China

Nineteen new cadinane-involving sesquiterpenoid dimers,artemordins A-S(1-—19),together with 13 known SDs(20-32)were isolated from Artemisia *** structures and absolute configurations were established by comprehensive spectral analyses,X-ray single crystal diffraction,theoretical ECD,and NMR ***,artemordins A-F(1—6)were the first examples of two cadinane units constructed by unprecedented C-3−C-15′or C-3−C-13′single bond with an oxido-rearranged 6/5/6/6 fused ring system;artemordins G-K(7-11)were biogenetically connected by[4+2]cycloaddition reaction and artemordins G-J(7-10)possessed a novel 5/6/6/6/6/6/5-heptacyclic fused ring *** L-S(12-19)were formed by esterification,which involved three different types of *** assay suggested that the most active compounds,artemordins B and H(2 and 8),exhibited inhibitory activities on three hepatoma cell lines with IC50 values of 26.9 and 25.1μmol/L(HepG2),29.5 and 18.3μmol/L(Huh7),19.7 and 15.7μmol/L(SK-Hep-1).

关键词： Artemisia ordosica Artemordins A-s Cadinane-type sesquiterpenoid dimers Antihepatoma activities Terpenoids Natural products Cytotoxicity

Characteristics of life-cycle carbon dioxide emissions of arterial highway maintenance and the influencing factors

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Advances in Climate Change Research 2024年第4期15卷 751-765页

作者： Yao wang yuan-Qing wang Shu-Juan ji Si-jia SUN Shu-Hong MA Ya-Nan GAO Key Laboratory of Transport Industry of Management Control and Cycle Repair Technology for Traffic Network Facilities in Ecological Security Barrier Area Chang'an UniversityXi'an 710064China Guangzhou Aids to Navigation Office Southem Navigation Service CenterMaritime Safety AdministrationGuangzhou 51000China

With the focus of highway development transitioning from construction to maintenance,a comprehensive understanding of the characteristics and influencing factors of carbon dioxide(CO_(2))emissions from highway maintenance activities is crucial for formulating effective strategies to promote the low-carbon development of road ***,the quantitative relationships between CO_(2) emissions from highway maintenance schemes and factors such as pavement deterioration,traffic volume,and road grade remain unclear owing to a lack of compre-hensive,multi-category,and real *** real maintenance data from 340 arterial highway segments in China,this study conducts the life cycle assessment(LCA)to estimate CO_(2) emissions from maintenance activities and examines the primary emission sources among various structural layers and ***,multiple linear regression(MLR)analysis is conducted to investigate the impact of traffic volume,road grade,and pavement deterioration on CO_(2) emissions from maintenance projects,and factors influencing the early-stage degradation of pavement *** results demonstrate that average CO_(2) emissions from heavy rehabilitation projects are 6.97 times higher than those from medium rehabilitation *** from heavy rehabilitation projects exhibit a significantly negative linear relationship with the riding quality index(RQI)before maintenance(p<0.05),and emissions from medium rehabilitation projects show a significant negative linear relationship with the pavement condition index(PCI)before maintenance(p<0.05).Emissions from heavy and medium rehabilitation projects are significantly positively correlated with heavy vehicle traffic volume before maintenance(p<0.05).Moreover,the early-stage degradation of PCI after heavy rehabilitation and RQI after medium rehabilitation exhibit significantly negative linear relationships with their respective in-dicators before maintenance(p<0.05).The early-stage d

关键词： Life cycle assessment(LCA) Arterial highway Maintenance Emission factor Pavement performance Traffic volume

Catalytic effects of V-and O-species derived from PrF_(3)/V_(2)C for efficient hydrogen storage in MgH_(2)

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Nano Research 2024年第8期17卷 7117-7125页

作者： Zhenluo yuan Yuhang wang Xiuxiu Zhang Shuyan Guan Xiaojiao wang Liqiang ji Qiuming Peng Shumin Han Yanping Fan Baozhong Liu College of Chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo 454000China Henan Famous Diamond Co. Ltd.Mengzhou 454763China School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

Magnesium hydride(MgH_(2))is considered as an ideal hydrogen storage material with excellent hydrogen capacity,but the slow kinetics impedes its ***,an efficient additive of V2C MXene-anchored PrF_(3) nanoparticles(PrF_(3)/V_(2)C)was synthesized,which presents excellent catalytic effect in improving the reversibility and stability of hydrogen storage in MgH_(2).The initial dehydrogenation temperature of the 5 wt.% PrF_(3)/V_(2)C-containing MgH_(2)(182℃) is 105℃ lower than that of pure MgH_(2),and 6.5 wt.%hydrogen is rapidly released from 5 wt.%PrF_(3)/V_(2)C-added MgH_(2)sample in 6 min at 240℃.In addition,5 wt.%PrF_(3)/V_(2)C-containing MgH_(2) sample possesses outstanding reversible hydrogen storage capability of 6.5 wt.% after 10 cycles of dehydrogenation and *** analysis shows that the introduction of Pr improves the stability of V-species(V^(0)and V^(2+))and O-species(lattice oxygen(OL)and vacancy oxygen(OV))formed during ball milling,promotes the interaction between V-species and O-species,and enhances their reversibility,which contributes to the significant improvement in re/dehydrogenation reversibility and cycling stability of MgH_(2).This study provides effective ideas and strategies for the purpose of designing and fabricating high-efficient catalysts for solid-state hydrogen storage materials.

关键词： hydrogen storage materials MgH_(2) dehydrogenation reversibility cyclic stability