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A novel ionic liquids grafted polysiloxane for capillary gas chromatography

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Chinese Chemical Letters 2009年第9期20卷 1111-1114页

作者： qing quan wei Mei Ling Qi Ruo Nong Fu Department of Chemistry School of Science Beijing Institute of Technology of China Beijing 100081 China

A new ionic liquids grafted polysiloxane used as stationary phase for capillary gas chromatography （CGC） is described. The stationary phase of 1-vinyl-3-hexylimidazolium hexafluorophosphate anchored to polysiloxane （PMHS-[VHIm][PF6]） was synthe- sized, characterized and coated onto capillary columns by static coating. The results show that the present stationary phase exhibits a very good chromatographic resolution and selectivity for Grob test mixture and alcohols with baseline resolution and symmetry peaks. The present work suggests that novel stationary phase has a great potential for further development and application. 2009 Mei Ling Qi. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Ionic liquids Polysiloxane Stationary phase Gas chromatography

Formation Mechanism and Binding Energy for Regular Octahedral Structure of Li_6 Cluster

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Communications in Theoretical Physics 2008年第12期50卷 1407-1410页

作者： ZHAO Yan-Ping LI Ping GOU qing-quan LIU wei-Na Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

The formation mechanism for the regular octahedral structure of Liscluster is proposed. The curve of the total energy versus the separation R between any two neighboring nuclei has been calculated by using the method of Gou＇s modified arrangement channel quantum mechanics （MACQM）. The result shows that the curve has a minimal energy of -44.736 89 a.u. at R = 5.07a0. When R approaches infinity, the total energy of six lithium atoms has the value of -44.568 17 a.u. So the binding energy of Li6 with respect to six lithium atoms is 0.1687 a.u. Therefore, the binding energy per atom for Li6 is 0.028 12 a.u., or 0.7637 eV, which is greater than the binding energy per atom of 0.453 eV for Li2 and the binding energy per atom of 0.494 eV for Li3 calculated in our previous work. This means that the Li6 cluster may be formed in a regular octahedral structure with a greater binding energy.

关键词： Li6 cluster formation mechanism binding energy

Dry eye and corneal sensitivity after small incision lenticule extraction and femtosecond laser-assisted in situ keratomileusis:a Meta-analysis

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International Journal of Ophthalmology(English edition) 2017年第4期10卷 632-638页

作者： Wen-Ting Cai qing-Yu Liu Cheng-Da Ren qing-quan wei Jun-Ling Liu Qian-Yi Wang Ya-Ru Du Meng-Mei He Jing Yu Department of Ophthalmology Shanghai Tenth People's Hospital Tongji University School of Medicine Shanghai 200072 China Nanchang University Nanchang 330031 Jiangxi ProvinceChina Nanjing Medical University Nanjing 210029 Jiangsu ProvinceChina

AIM：To assess the corneal sensitivity and the incidences of dry eye after small incision lenticule extraction（SMILE） and femtosecond laser-assisted in situ keratomileusis（FSLASIK）.METHODS：The Meta-analysis was performed using Rev Man *** searched on Pub Med from inception to March *** weighted mean difference（WMD） and 95% confidence intervals（CIs） were used to analyze the ***-effects or fixed-effects models were chosen up to between-study *** main outcomes were composed of the Ocular Surface Disease Index（OSDI） scores,tear film break-up time（TBUT）,Schirmer Test and corneal ***：Eight eligible studies including 772 eyes（386 in SMILE group and 386 in FS-LASIK group） were *** parameters have no significiant difference heterogeneity between SMILE and FS-LASIK group *** were significant differences between the two groups in OSDI scores at one and three months postoperatively,in TBUT at one and three months postoperatively,in corneal sensitivity at one week,about one month and three months ***,there was no significant difference observed in Schirmer Test at the follow-up ***：Compare to FS-LASIK,dry eye and the corneal sensitivity recover better in the SMILE group,in first three months after the surgery.

关键词： dry eye corneal sensation small incision lenticule extraction femtosecond laser-assisted in situ keratomileusis Meta-analysis

Visual electrophysiological assessment of children with poor response to treatment for functional amblyopia

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International Journal of Ophthalmology(English edition) 2025年第2期18卷 315-322页

作者： Dong-qing Yuan wei-wei Zhang Liu-wei Gu qing-Huai Liu Department of Ophthalmology Jiangsu Province Hospitalthe First Affiliated Hospital of Nanjing Medical UniversityJiangsu Women and Children Health HospitalNanjing 210029Jiangsu ProvinceChina

AIM:To assess the visual electrophysiological outcomes in children with functional amblyopia who exhibited poor response to conventional ***:Twenty-one children with functional amblyopia,aged 5.7±2.1y(range:4-10y),underwent comprehensive ophthalmic and refractive *** domain-optical coherence tomography(SD-OCT)and multifocal electroretinography(mfERG)were conducted to analyze the macular retinal thickness and the first-order response P1 ring of the mfERG in the amblyopic eye(AE)compared to the fellow good eye(GE).RESULTS:Initially,visual acuity in the AE ranged from 20/800 to 20/40,while the GE exhibited a range of 20/25 to 20/20(P<0.01).After 6mo of treatment,17 patients demonstrated improved visual acuity in the AE to 20/50 or better,while 4 children showed no ***-OCT revealed comparable macular and optic disc structures between the AE and *** to treatment,the mfERG P1 ring amplitude was significantly reduced in the AE compared to GE(P<0.05).The AE/GE ratio of P1 ring amplitude showed significant improvement ***,a smaller AE/GE ratio before treatment was associated with poorer improvement ***:In the management of functional amblyopia,a thorough assessment of amblyopic eye examinations is *** 20%of amblyopic eyes may not achieve significant improvement in visual acuity,despite the absence of detectable organic retinal *** may reveal underlying *** mfERG into initial assessments or treatment follow-ups can aid in identifying potential hidden retinal defects and predicting the prognosis of the amblyopic eye.

关键词： functional amblyopia poor response optical coherence tomography multifocal electroretinography retinal defects

Enantioselective reductive conjugate alkenylation ofα,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第1期68卷 157-162页

作者： Rong-De He Yun-Lei Luo Qiu-quan Pan Qi-wei Yao Xing-Zhong Shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis,yet their asymmetric variant remains ***,asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–*** manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl *** method facilitates the enantioselective addition of keto alkenyl groups toα,β-enones,resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access *** use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

Numerical simulation of microstructure and microporosity morphology in directional solidification of aluminum-copper alloys:Effect of copper content and withdrawal rate

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China Foundry 2025年第1期22卷 33-44页

作者： wei Yuan Hai-dong Zhao Xu Shen Chun Zou Yuan Liu qing-yan Xu National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) Tsinghua UniversityBeijing 100084China

Microporosity formed in the solidification process of Al alloys is detrimental to the alloy properties.A two-dimensional cellular automaton(CA)model was developed to simulate the microstructure and microporosity formation in Al-Cu alloys,considering variations in Cu content and solidification *** results indicate that the Cu content primarily influences the growth of *** validate the model,directional solidification experiments were conducted on Al-Cu alloys with varing Cu contents and withdrawal *** experimental results of dendrites and microporosity characteristics agree well with the predictions from the developed model,thus confirming the validity of the *** alloy’s liquidus temperature,dendrite morphology,and hydrogen saturation solubility arising from different Cu contents have significant effects on microporosity *** withdrawal rate primarily affects the nucleation of hydrogen microporosity by altering cooling rates and dendritic growth rates,resulting in different microporosity characteristics.

关键词： microporosity dendrites cellular automaton Al-Cu alloys directional solidification

Prospects on mangrove knowledge services in the smart era:From plant atlas to knowledge graphs

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Science China Earth Sciences 2025年第1期68卷 111-127页

作者： Zhi-wei HOU Wenlong JING Cheng-Zhi QIN Ji YANG qing XIA Xiaoling YIN Key Laboratory of Guangdong for Utilization of Remote Sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and ApplicationGuangzhou Institute of GeographyGuangdong Academy of SciencesGuangzhou510070China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou511458China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China School of Traffic&Transportation Engineering Changsha University of Science and TechnologyChangsha410114China

Mangroves are crucial to the ecological security of the Earth and human *** management,conservation,and restoration are of great importance and necessitate the support of spatio-temporal information and multidisciplinary knowledge such as biology and *** knowledge services such as plant atlas provide illustrated textual knowledge of ***,this kind of service is oriented to information retrieval and is incapable of effectively mining and utilizing fragmented knowledge from multi-source heterogeneous data,facing the problem of“massive data,rare knowledge”.Knowledge graphs are capable of extracting,organizing,and fusing the knowledge contained in massive data into semantic networks that can be understood and computed by *** provide a solution for the realization of intelligent knowledge *** on the urgent need for mangrove knowledge acquisition,formal representation,and intelligent services,this paper proposes a research prospect on mangrove knowledge graphs and knowledge *** first analyze the similarities and differences between various domain-specific concepts of *** this basis,we define the mangrove knowledge graph as a large-scale knowledge base that integrates multi-disciplinary knowledge and spatio-temporal information with mangrove ecosystems as the ***,we propose a research framework for mangrove knowledge services that can realize the transformation from multi-modal data to intelligent knowledge services,including multiple research levels such as ubiquitous data sensing and aggregation,knowledge organization and graph construction,and intelligent mangrove knowledge ***,the methods and workflow for constructing mangrove knowledge graphs are ***,we discuss the challenges and possible future directions of mangrove knowledge services in the smart era,including the construction of a mangrove knowledge system that integrates the domain-specific charac

关键词： Mangrove Tupu Knowledge graph Multi-modal Knowledge service

Recent advances of cerium compounds in functional coatings:Principle,strategies and applications

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Journal of Rare Earths 2025年第2期43卷 227-245页

作者： Kai An Youqiang Wang Yi Sui Yongquan qing wei Tong Xuezhao Wang Changsheng Liu School of Mechanical and Automotive Engineering Qingdao University of Technology State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare Earths School of Materials Science and Engineering Northeastern University Center for Nano and Micro Mechanics Tsinghua University

Cerium(Ce) compounds have attracted considerable attention as key components in functional coatings due to their many outstanding *** work provides a comprehensive review of recent advances in the application of Ce in functional *** role of Ce in the improvement of functional properties such as corrosion-resistance,self-healing,superhydrophobicity,wear-resistance,and UV shielding is reviewed from the perspective of functional mechanism and applied ***,the strategies,processes,practical problems,and current challenges in the research of functional coatings containing Ce are summarized and *** objective is to highlight the great potential of Ce in functional coatings,and to explore new applications of Ce in the development of novel ***,this work aims to enhance the application value of Ce,solving the problem of unbalanced application of rare-earth elements.

关键词： Cerium Functional coatings Corrosion Superhydrophobicity UV resistance Rare earths

Optimizing cooling approach of spiral coil for an electromagnetic steel teeming system of ladle in continuous casting production

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Journal of Iron and Steel Research International 2025年第1期32卷 85-94页

作者： Ming He qing-wei Wang Li-jia Zhao Wang-zhong Mu Xing-an Liu Qiang Wang College of Horticulture Shenyang Agricultural UniversityShenyang110866LiaoningChina Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang110819LiaoningChina Key Laboratory of Protected Horticulture(Ministry of Education) Shenyang Agricultural UniversityShenyang110866LiaoningChina Department of Materials Science and Engineering KTH Royal Institute of TechnologyStockholm10044Sweden

To address the current issues with the conventional slide gate system utilized in the steel teeming process,a unique electromagnetic induction controlled automated steel teeming(EICAST)technology has been *** means of spiral coil in this technology is directly related to its service ***,heat transfer processes of air cooling and spray cooling were compared and ***,the impacts of water temperature,water flow rate and air flow rate were examined in order to maximize the spray cooling *** maintain coil temperature at a low value consistently throughout the entire thermal cycle process of the ladle,a combined cooling mode was finally *** simulation was applied to examine the coil temperature variation with different cooling systems and *** coil operation,spray cooling is said to be more *** controlling the water flow rate and air flow rate,the spray cooling effect is ***,water temperature has little or no impact when using spray *** cooling during the secondary refining process and spray cooling prior to coil operation are combined to further lower coil *** the direction of the spray cooling is from bottom to top,the coil temperature is lowered below 165℃.A practical induction coil cooling plan was provided for the EICAST technology’s production process.

关键词： Electromagnetic induction controlled automated steel teeming technology Spiral coil Spray cooling Heat transfer Continuous casting