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A light-through-side cell and co-used furnace designed for micro-Raman spectra study on volatile melts

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Chinese Chemical Letters 2012年第11期23卷 1291-1294页

作者： Xian Wei Hu Huan Li bing liang gao Jing Jing Liu Zhong Ning Shi Jiang Yu Yu Zhao Wen Wang School of Materials and Metallurgy Northeastern UniversityShenyang 110004China

A new type of sample cell specially designed for micro-Raman spectra study on volatile melts is described. The cell is made of quartz. The lower section of the cell is circular ring-shaped and the one-end-closed hole in the cell is used for locating the heating body. The tube attached to the cell lid for placing the thermal couple is inserted into the sample, which ensures that the temperature measurement accuracy is good. The cell can be sealed for reducing the effect of the composition change caused by the in_homogeneous volatilization. During the Raman spectra scanning, the laser beam is transmitted into the cell through the side but not the top. Meanwhile, a furnace has been designed to match the cell. The heating body is closely coupled with the sample cell, and there is a hole on the side wall of the furnace for the entrance of the microlens. The assembly has performed well in the tested Raman spectrum measurement of molten NaNO3 at 602 ℃.

关键词： Light-through-side cell Raman spectroscopy Volatile melts Comer microlens Cell-around-heating body furnace

Sufficient Conditions for Amalgamated 3-Manifolds to be ∂-Irreducible

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 161-172页

作者： bing FANG Fengchun LEI liang liang School of Mathematical Sciences Dalian University of TechnologyDalian 116024LiaoningChina School of Mathematics Liaoning Normal UniversityDalian 116029LiaoningChina

In this paper,the authors give some sufficient conditions for an amalgamated 3-manifold along a compact connected surface F with boundary to be ∂-irreducible in terms of distances between some kinds of vertex subsets ... 详细信息

关键词： ∂-Irreducibility Irreducibility Amalgamated 3-manifold Curve complex Arc complex

Quasi-two-dimensional strong liquid-like dynamics of surface atoms in metallic glasses

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 102-109页

作者： bing Wang Xuanqiao gao Rui Su Pengfei Guan School of Physical Science and Technology Northwestern Polytechnical UniversityXi'an 710072China Innovation Center NPU Chongqing Northwestern Polytechnical UniversityChongqing 401135China School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710072China Northwest Institute for Nonferrous Metal Research Xi'an 710016China Institute of Advanced Magnetic Materials College of Materials and Environmental EngineeringHangzhou Dianzi University Hangzhou 310018China Beijing Computational Science Research Center Beijing 100093China

The fast dynamic properties of the surface of metallic glasses(MGs) play a critical role in determining their potential applications. However, due to the significant difference in thermal history between atomic simulation models and laboratory-made samples, the atomic-scale behaviors of the fast surface dynamics of MGs in experiments remain uncertain. Herein, we prepared model MG films with notable variations in thermal stability using a recently developed efficient annealing protocol, and investigated their atomic-scale dynamics systematically. We found that the dynamics of surface atoms remain invariant, whereas the difference in dynamical heterogeneity between surface and interior regions increases with the improvement of thermal stability. This can be associated with the more pronounced correlation between atomic activation energy spectra and depth from the surface in samples with higher thermal stability. In addition, dynamic anisotropy appears for surface atoms, and their transverse dynamics are faster than normal components, which can also be interpreted by activation energy spectra. Our results reveal the presence of strong liquid-like atomic dynamics confined to the surface of laboratory-made MGs, illuminating the underlying mechanisms for surface engineering design, such as cold joining by ultrasonic vibrations and superlattice growth.

关键词： metallic glasses thermal stability invariant surface dynamics potential energy landscape dynamic anisotropy and heterogeneity

Universal origin of glassy relaxation as recognized by configuration pattern matching

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National Science Review 2024年第5期11卷 343-351页

作者： Hai-Bin Yu liang gao Jia-Qi gao Konrad Samwer Wuhan National High Magnetic Field Center and School of Physics Huazhong University of Science and Technology I.Physikalisches Institut Universit?t G?ttingen

Relaxation processes are crucial for understanding the structural rearrangements of liquids and amorphous materials. However, the overarching principle that governs these processes across vastly different materials remains an open question. Substantial analysis has been carried out based on the motions of individual particles. Here, as an alternative, we propose viewing the global configuration as a single entity. We introduce a global order parameter, namely the inherent structure minimal displacement(IS Dmin), to quantify the variability of configurations by a pattern-matching technique. Through atomic simulations of seven model glass-forming liquids, we unify the influences of temperature, pressure and perturbation time on the relaxation dissipation, via a scaling law between the mechanical damping factor and IS Dmin. Fundamentally,this scaling reflects the curvature of the local potential energy landscape. Our findings uncover a universal origin of glassy relaxation and offer an alternative approach to studying disordered systems.

关键词： glass transition metallic glass relaxation dynamics mechanical spectroscopy internal friction

A Study on the Impact of Chemical Structure on the Evolution of Aggregate Structure in Fiber-shaped High Density Polyethylene Vitrimer

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Chinese Journal of Polymer Science 2024年第10期42卷 1557-1565,I0013页

作者： bing Wang Yuan-Chu gao Hai Wang Hui Niu State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian116024China

Vitrimers have emerged as a prominent research area in the field of polymer *** of the studies have focused on synthesizing polymers with versatile dynamic crosslinking structures,while the impact of chemical structure on aggregate structure of vitrimers,particularly during polymer processing,remains insufficiently *** present study employed commercial maleic anhydride-grafted-high density polyethylene(M-g-HDPE)as the matrix and hexanediol as the crosslinker to facilely obtain fiber-shaped HDPE vitrimers through a reaction extrusion and post-drawing *** chemical structure characterization,morphology observation,thermal and mechanical properties investigation,as well as aggregate structure analysis,this work revealed the influence of dynamic bonds on the formation of aggregate structures during fiber-shaped vitrimers processing.A small amount of dynamic bonds in HDPE restricts the motion of PE chain during melt-extruding and post-drawing,resulting in a lower orientation of the PE ***,lamellar growth and fibril formation during post-drawing at high temperature are enhanced to some extent due to the competition between dynamic bond and chain *** uneven morphology of fibershaped HDPE vitrimers can be attributed to the stronger elastic effect brought by dynamic bonding,which plays a more dominant role in determining the mechanical properties of fiber-shaped vitrimers compared to aggregate *** Vitrimers have emerged as a prominent research area in the field of polymer *** of the studies have focused on synthesizing polymers with versatile dynamic crosslinking structures,while the impact of chemical structure on aggregate structure of vitrimers,particularly during polymer processing,remains insufficiently *** present study employed commercial maleic anhydride-grafted-high density polyethylene(M-g-HDPE)as the matrix and hexanediol as the crosslinker to facilely obtain fiber-shap

关键词： High density polyethylene vitrimer Fiber-shaped Aggregate structures Transesterification reaction

Water and other volatiles on Mars

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National Science Review 2024年第6期11卷 12-14页

作者： Sen Hu Yubing gao Zhan Zhou liang gao Yangting Lin Key Laboratory of the Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences

Mars, the intriguing red planet, is one of the planets most similar to the Earth in our solar system. It is widely accepted that Mars could have had a warm and wet climate in its early history supported by numerous lines of evidence, e.g. topography, canyons, outflow channels, presence of phyllosilicates and evaporative salts,sedimentary formation, and many others (e.g.[1]), and thus Mars is believed to once have a potentially habitable environment which could be able to supply fundamental conditions for the evolution of potential lives.

关键词： ISOTOPIC COMPOSITION MARTIAN ATMOSPHERE SUBSURFACE WATER ABUNDANCE TISSINT H2O CO2

Creating one-line hybrid crops by synthetic apomixis

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Molecular Plant 2024年第1期17卷 16-18页

作者： Ronghong liang Caixia gao New Cornerstone Science Laboratory Center for Genome EditingInstitute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing100101China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing100049China

Hybrid breeding plays an important role in increasing crop yields by taking advantage of hybrid vigor,which helps crops grow with superior yields across various climates and contributes to ensuring secure food *** seed production is relatively straightforward and simple in cross-pollinating plants such as maize but is difficult in self-pollinating plants such as rice,wheat,and ***,breeders have developed a three-line breeding strategy,utilizing a sterile line,a maintainer line,and a restorer line,for breeding hybrid rice(Figure 1A;Yuan,1966).

关键词： breeding crops sterile

Exploring the impact of economic growth and energy consumption on SO2 emissions in China based on the Environmental Kuznets Curve hypothesis

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Petroleum Science 2024年第4期21卷 2892-2900页

作者： bing-Jie Xu Yi-Fei Shen Hui Qiao Zhi gao Faculty of Business City University of Macau Rural Development Institute Chinese Academy of Social Sciences School of Marxism Shenzhen Polytechnic University

This study aims to analysis the influence of economic growth(EG) and energy consumption(EC) on sulfur dioxide emissions(SE) in China. Accordingly, this study explores the link between EG, EC, and SE for 30 provinces in China over the span of 2000-2019. This study also analyzes cross-sectional dependence tests, panel unit root tests, Westerlund panel cointegration tests, Dumitrescu-Hurlin(D-H) causality tests. According to the test results, there is an inverted U-shaped association between EG and SE,and the assumption of the Environmental Kuznets Curve(EKC) is verified. The signs of EG and EC in the fixed effect(FE) and random effect(RE) methods are in line with those in the dynamic ordinary least squares(DOLS), fully modified ordinary least squares(FMOLS) and autoregressive distributed lag(ARDL)estimators. Moreover, the results verified that EC can obviously positive impact the SE. To reduce SE in China, government and policymakers can improve air quality by developing cleaner energy sources and improving energy efficiency. This requires the comprehensive use of policies, regulations, economic incentives, and public participation to promote sustainable development.

关键词： SO 2 emissions Economic growth Energy consumption EKC China

Effect of mesopore spatial distribution of HZSM-5 catalyst on zinc state and product distribution in 1-hexene aromatization

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Chinese Journal of Chemical Engineering 2024年第3期67卷 16-26页

作者： Chenhao Wei Di gao Guohao Zhang liang Zhao Jinsen gao Chunming Xu The State Key Lab of Heavy Oil Processing China University of Petroleum(Beijing)Beijing 102249China SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China

1-hexene aromatization is a promising technology to convert excess olefin in fluid catalytic cracking(FCC)gasoline to high-value benzene(B),toluene(T),and ***,the increasing market demand of xylene has put forward higher requirements for new generation of *** increasing xylene yield in 1-hexene aromatization,the effect of mesopore structure and spatial distribution on product distribution and Zn loading was *** with different mesopore spatial distribution were prepared by post-treatment of parent HZSM-5 zeolite,including NaOH treatment,tetra-propylammonium hydroxide(TPAOH)treatment,and *** was found the evenly distributed mesopore mainly prolongs the catalyst lifetime by enhancing diffusion properties but reduces the aromatics selectivity,as a result of damage of micropores close to the catalyst *** the selectivity of high-value xylene can be highly promoted when the mesopore is mainly distributed interior the ***,the state of loaded Zn was also affected by mesopores spatial *** the optimized catalyst,the xylene selectivity was enhanced by 12.4%compared with conventional Zn-loaded parent HZSM-5 catalyst at conversion over 99%.It was attributed to the synergy effect of mesopores spatial distribution and optimized acid *** work reveals the role of mesopores in different spatial positions of 1-hexene aromatization catalysts in the reaction process and the influence on metal distribution,as well as their synergistic effect two on the improvement of xylene selectivity,which can improve our understanding of catalyst pore structure and be helpful for the rational design of high-efficient catalyst.

关键词： 1-Hexene aromatization Alkali treatment Xylene selectivity Mesopores Zinc state