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Journal of Mountain Science 2017年第3期14卷 549-557页

作者： HU Chun-sheng HU chen-qi liu shao-chen XU Guang-lai WU Li YANG Li-hui College of Territorial Resources and Tourism Anhui Normal UniversityWuhu 241000China Anhui Key Laboratory of Natural Disaster Process and Preventing and Controlling Wuhu 241000China

On the northern fringe of Mt. Huangshan, many fiver terraces are developed at the junction between mountains and plains. The fiver terraces are most typical in the Jingxian Basin, Anhui Province, where the Qingyijiang River, one of the longest tributaries of the lower Yangtze River, developed three staircase terraces. The topmost terrace （i.e., the T3 terrace） tread is 38 - 39 m above fiver level, and the top of the gravels is generally covered by 3 - 10.9 m of red clay deposits. Systematic magnetostratigraphy and electron spin resonance dating are used to research the timing of the establishment of the Qingyijiang River. The main results show that the topmost terrace developed no later than 900 kyr ago and that the appearance of the Qingyijiang River occurred correspondingly at least before 900 kyr ago on the northern fringe of Mt. Huangshan. In view of the almost synchronous age,the establishment of the Qingyijiang River was seemingly a response to the Mid-Pleistocene Revolution when the 100 kyr cycle commenced, and the Kunlun-Huanghe movement during the early- middle Pleistocene transition. In addition, the establishment of the Qingyijiang River possibly reflected the birth of the modem Yangtze River to some degree. Therefore the timing of the formation of the Yangtze River is restricted to no later than 900 kyr ago based on the appearance of the Qingyijiang River .

关键词： Qingyijiang River Topmost terrace Magnetostratigraphy Electron Spin Resonance dating Establishment timing Jingxian Basin

The reaction mechanism and interfacial crystallization of Al nanoparticle-embedded Ni under shock loading

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Defence Technology（防务技术） 2024年第3期33卷 114-124页

作者： Yifan Xie Jian-Li shao Rui liu Pengwan chen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Explosion Protection and Emergency Disposal Technology Engineering Research Center of the Ministry of Education Beijing100039China

The shock-induced reaction mechanism and characteristics of Ni/Al system,considering an Al nanoparticle-embedded Ni single crystal,are investigated through molecular dynamics *** the shock melting of Al nanoparticle,interfacial crystallization and dissolution are the main *** reaction degree of Al particle first increases linearly and then logarithmically with time driven by rapid mechanical mixing and following *** reaction rate increases with the decrease of particle diameter,however,the reaction is seriously hindered by interfacial crystallization when the diameter is lower than 9 nm in our ***,we found a negative exponential growth in the fraction of crystallized Al atoms,and the crystallinity of B2-NiAl(up to 20%)is positively correlated with the specific surface area of Al *** can be attributed to the formation mechanism of B2-NiAl by structural evolution of finite mixing layer near the collapsed *** shock melting of both Al particle and Ni matrix,the liquid-liquid phase inter-diffusion is the main reaction mechanism that can be enhanced by the formation of internal *** addition,the enhanced diffusion is manifested in the logarithmic growth law of mean square displacement,which results in an almost constant reaction rate similar to the mechanical mixing process.

关键词： Shock-induced reaction Molecular dynamics simulations Interfacial crystallization Reaction mechanism

Effect of nano-carbon black content on wetting phenomenon of molten steel and alumina-carbon ceramic filter substrates

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Journal of Iron and Steel Research International 2024年第8期31卷 1900-1913页

作者： Jin-wen Song Wen Yan Zhe chen Ying liu shao-song Hong The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina National-provincial Joint Engineering Research Center of High Temperature Materials and Lining Technology Wuhan University of Science and TechnologyWuhan 430081HubeiChina Jiangsu Sheng Nai New Materials Co. Ltd.Taizhou 225503JiangsuChina

The effect of nano-carbon black content(O,8 and 12 wt.%)on the wettability of molten steel on Al_(2)O_(3)-C substrates was investigated by the sessile drop wetting method at 1500℃ under argon *** the beginning of the wetting experiment,the contact angle decreased with the increase in nano-carbon black *** the wetting experiment progressed,FeAl_(2)0_(4) layer and sheet Al_(2)O_(3) layer were found at the interface between the molten steel and the Al_(2)O_(3)-C substrates with O and 8 wt.% nano-carbon black content,and the contact angle deceased with *** the content of nano-carbon black was 12 wt.%,a large number of nano-Al_(2)O_(3) whiskers were observed,which made the contact angle between the molten steel and Al_(2)O_(3)-C substrate become *** on the scanning electron microscope and energy dispersive spectrometry results,the formation mechanism of FeAl2O4 layer and Al_(2)O_(3) layer and the interfacial reaction mechanism were proposed.

关键词： Contact angle Nano-carbon black Al_(2)O_(3)-C substrate Molten steel Interfacial reaction

Asymmetric alkenylation reaction of benzoxazinones with diarylethylenes catalyzed by B(C_(6)F_(5))_(3)/chiral phosphoric acid

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Chinese Chemical Letters 2024年第5期35卷 135-140页

作者： Zhen liu Zhi-Yuan Ren chen Yang Xiangyi shao Li chen Xin Li State Key Laboratory of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhenhai High School of Zhejiang Ningbo 315299China

Catalytic enantioselective alkenylation is an efficient method to construct chiral alkene molecules,but the asymmetric alkenylation of simple alkenes catalyzed by metal-free catalysts remains an elusive ***,we reported an asymmetric alkenylation of benzoxazinones with diarylethylenes by utilizing a B(C_(6)F_(5))_(3)/chiral phosphoric acid catalyst.A broad of benzoxazinones and diarylethylenes with electron-withdrawing and electron-donating groups were tolerated(up to 95%yield and 97.5:2.5 e.r.)in the methodology under mild reaction ***,the synthetic utility was confirmed by the scaled-up reaction and transformations of the *** mechanism was preliminarily explored by control reactions,nonlinear effect experiment and DFT calculations.

关键词： Asymmetric alkenylation Simple alkenes Benzoxazinones B(C_(6)F_(5))_(3)/chiral phosphoric acid Theoretical calculations

Influence on Biological Behavior of Colon Cancer Stem Cells after RNA Interfering CD133

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Clinical oncology and cancer researeh 2010年第6期7卷 359-365页

作者： Liang AI Mei liu Mi chen shao-lin LI Teaching and Research Section of Radiation Medicine School of Basic Medical Science Chongqing Medical University Chongqing 400016. China.

OBJECTIVE To observe the effects expression and activation on biological cancer stem cells. of blocking CD133 gene characteristic of the colon METHODS CD133＋ colon cancer stem cells （CCSCs） were separated from EpCAMhigh CD44＋ CCSCs through fluorescenceactivated cell sorting （FACS）. The proliferation, the capability of spherical cell formation, neoplasia, and the expression of ABCG2 mRNA of CD133＋ CCSCs were observed after the CD133＋ CCSCs were infected with LV-CD133shRNA. CD133 negative cells were isolated from EpCAMhigh CD44＋ CCSCs with FACS, and the CD133 proteins in CD133- cells were detected with Western blot. RESULTS CD133＋ CCSCs were isolated from EpCAMhigh CD44＋ CCSCs using FACS, and they accounted for 89.2% in the stem cells. In the experimental group, after the CD133＋ CCSCs were knocked down by LV-CD133shRNA RNAi, the growth pattern of the cells in the stem cell culture changed into adherent growth from suspended growth, and couldn＇t generate spherical cells. Results of MTT assay showed that the CD133＋ CCSCs infected with LV-CD133shRNA grew slowly, compared to the cells in the control groups. There was a decrease in the cloning efficiency. The infected cells were transplanted into the BALB/c nude mice. During the observation, no neoplasia was found in the CD133＋ cells infected with LV-CD133shRNA. The level of ABCG2 mRNA expression was lowered greatly （P 〈 0.01）. CD133- cells were obtained from the EpCAMhigh CD44＋ CCSCs using FACS, in which the expression of CD133 protein was positive. CONCLUSION CD133 retains the biological characteristics of the colon cancer stem cells.

关键词： colonic neoplasms stem cells CD133 protein mouse RNA interference biological behavior.

Purification performance on molten steel of novel Al_(2)O_(3)-based ceramic filter prepared from microporous powder and nano-Al_(2)O_(3) powder

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Journal of Iron and Steel Research International 2024年第6期31卷 1535-1546页

作者： Zhe chen Wen Yan Ying liu Guang-qiang Li shao-song Hong Nan Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Jiangsu Shengnai New Materials Co. Ltd.Taizhou 225534JiangsuChina

Reticulated ceramic foam filters provide an effective way to purify molten steel by removing non-metallic *** proposed a novel strategy to improve the purification performance of Al_(2)O_(3)-based ceramic filters by using microporous corundum-spinel raw materials to replace dense raw *** kinds of Al_(2)O_(3)-based ceramic filters fabricated from dense α-Al_(2)O_(3) micro-powder or microporous corundum-spinel powder were selected to carry out the immersion tests with molten *** the one hand,the higher surface roughness of the filter skeleton prepared from microporous raw materials increased the adsorption capacity of skeleton surface on inclusions in molten *** the other hand,the higher apparent porosity and larger pore size of the filter skeleton were more beneficial to the penetration of molten steel in the micropores of *** reaction process at the solid-liquid interface also improved the wettability of the interface between skeleton and molten steel,resulting in a larger penetration depth and a better adsorption effect on the *** summary,the novel Al_(2)O_(3)-based ceramic filter prepared with microporous corundum-spinel powder and addition of 5 wt.% nano-Al_(2)O_(3) powder reduced the total oxygen content of the steel from 40.2×10^(-4) to 12.7×10^(-4) wt.% by 68.4% and the Al content from 0.46 to 0.18 wt.% by 60.9% after immersion test,presenting the most excellent purification performance on molten steel.

关键词： Al_(2)O_(3)-based ceramic filter Microporous corundum-spinel powder Non-metallic inclusion-Microstructure Molten steel purification

A Transparent Photoresist Made of Titanium Dioxide Nanoparticle-Embedded Acrylic Resin with a Tunable Refractive Index for UV-Imprint Lithography

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Engineering 2024年第6期37卷 96-104页

作者： Yinglu liu Dan Wang Changlin liu Qianqian Hao Jian Li Jie-Xin Wang Xiuyun chen Peng Zhong Xibin shao Jian-Feng chen State Key Laboratory of Organic–Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China BOE Technology Group Co. Ltd.Beijing 100176China

Transparent photoresists with a high refractive index(RI)and high transmittance in visible wavelengths have promising functionalities in optical *** work reports a kind of tunable optical material composed of titanium dioxide nanoparticles embedded in acrylic resin with a high RI for ultraviolet(UV)-imprint *** hybrid film exhibits a tunable RI of up to 1.67(589 nm)after being cured by UV light,while maintaining both a high transparency of over 98%in the visible light range and a low haze of less than 0.05%.The precision machining of optical microstructures can be imprinted easily and efficiently using the hybrid resin,which acts as a light guide plate(LGP)to guide the light from the side to the top in order to conserve the energy of the display *** preliminary studies based on both laboratory and commercial experiments pave the way for exploiting the unparalleled optical properties of nanocomposite resins and promoting their industrial application.

关键词： Photoresist Tunable refractive index Hanson solubility Ultraviolet imprint Organic-inorganic composites

Edge effect during microwave plasma chemical vapor deposition diamond-film:Multiphysics simulation and experimental verification

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2287-2299页

作者： Zhiliang Yang Kang An Yuchen liu Zhijian Guo Siwu shao Jinlong liu Junjun Wei Liangxian chen Lishu Wu chengming Li Institute of Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China Shunde Innovation School University of Science and Technology BeijingFoshan 528399China National Key Laboratory of Solid-State Microwave Devices and Circuits The 55th Research Institute of China Electronics Technology Group CorporationNanjing 210016China

This study focused on the investigation of the edge effect of diamond films deposited by microwave plasma chemical vapor *** bulge height△h is a factor that affects the edge effect,and it was used to simulate plasma and guide the diamond-film deposition ***-element software COMSOL Multiphysics was used to construct a multiphysics(electromagnetic,plasma,and fluid heat transfer fields)coupling model based on electron collision *** spectroscopy and scanning electron microscopy were performed to characterize the experimental growth and validate the *** simulation results reflected the experimental trends *** discharge at the edge of the substrate accelerated due to the increase in△h(△h=0-3 mm),and the values of electron density(n_(c)),molar concentration of H(C_(H)),and molar concentration of CH_(3)(C_(CH_(3)))doubled at the edge(for the special concave sample with△h=−1 mm,the active chemical groups exhibited a decreased molar concentration at the edge of the substrate).At=0-3 mm,a high diamond growth rate and a large diamond grain size were observed at the edge of the substrate,and their values increased *** uniformity of film thickness decreased *** Raman spectra of all samples revealed the first-order characteristic peak of dia-mond near 1332 cm^(−1).When△h=−1 mm,tensile stress occurred in all regions of the ***△h=1-3 mm,all areas in the film ex-hibited compressive stress.

关键词： microwave plasma chemical vapor deposition edge discharge plasma diamond film

Thermodynamic nature of black holes in coexistence region

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 27-32页

作者： shao-Wen Wei Yu-Xiao liu Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Provinceand Key Laboratory of Quantum Theory and Applications of Mo ELanzhou UniversityLanzhou 730000China Institute of Theoretical Physics&Research Center of Gravitation Lanzhou UniversityLanzhou 730000China

Studying the system state of coexistence regions will peek into to reveal microscopic interactions between different phases of a thermodynamic ***,there is no effective method to study thermodynamic nature of the coexistence black hole regions for the failure of the equation of *** at these coexistence states,in this work,we develop a general approach by introducing two new ratio *** first one is the ratio of the horizon radii of the saturated coexistence small and large black holes,and the second one measures that of the small black hole molecule number to the total molecule *** demonstrate that the first parameter can serve as an order parameter to characterize the first-order phase *** study also shows that the black hole state in the coexistence region is uniquely determined by these two introduced parameters bounded between 0 and *** results are quite significant in the analytical study of phase transition and the microscopic nature of black hole in the coexistence regions.

关键词： transition. state. thermodynamic

3D printing of poly(ethyleneimine)-functionalized Mg-Al mixed metal oxide monoliths for direct air capture of CO_(2)

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Journal of Energy Chemistry 2024年第9期96卷 491-500页

作者： Qingyang shao Zhuozhen Gan Bingyao Ge Xuyi liu Chunping chen Dermot O’Hare Xuancan Zhu Research Center of Solar Power&Refrigeration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Chemistry Research Laboratory Department of ChemistryUniversity of OxfordOxford OX13TAUK

Direct air capture(DAC)of CO_(2)plays an indispensable role in achieving carbon-neutral goals as one of the key negative emission *** large air flows are required to capture the ultradilute CO_(2)from the air,lab-synthesized adsorbents in powder form may cause unacceptable gas pressure drops and poor heat and mass transfer efficiencies.A structured adsorbent is essential for the implementation of gas-solid contactors for cost-and energy-efficient DAC *** this study,efficient adsorbent poly(ethyleneimine)(PEI)-functionalized Mg-Al-CO_(3)layered double hydroxide(LDH)-derived mixed metal oxides(MMOs)are three-dimensional(3D)printed into monoliths for the first time with more than 90%adsorbent *** printing process has been optimized by initially printing the LDH powder into monoliths followed by calcination into MMO *** structure exhibits a 32.7%higher specific surface area and a 46.1%higher pore volume,as compared to the direct printing of the MMO powder into a *** impregnation of PEI,the monolith demonstrates a large adsorption capacity(1.82 mmol/g)and fast kinetics(0.7 mmol/g/h)using a CO_(2)feed gas at 400 ppm at 25℃,one of the highest values among the shaped DAC *** of the amino-polymers during the post-printing process affects the diffusion of CO_(2),resulting in slower adsorption kinetics of pre-impregnation monoliths compared to post-impregnation *** optimal PEI/MeOH ratio for the post-impregnation solution prevents pores clogging that would affect both adsorption capacity and kinetics.

关键词： 3D printing Mixed metal oxides Amine functionalization Structured adsorbent Direct air capture