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Silicon Pick-up of Interstitial-Free Steel From MgO-SiC Refractories

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Journal of Iron and Steel Research International 2008年第3期15卷 92-94,69页

作者： WEI Yao-wu LI Nan chen xiao-xia HU Tie-shan RAO Jiang-ping TAO xiao-lin Hubei Province Key Lab of Refarctories and Ceramics Wuhan University of Science and Technology Wuhan 430081 Hubei China No. 3 Steelmaking Plant of Wuhan Iron and Steel Group Corporation Wuhan 430082 Hubei China

The silicon pick-up of interstitial-free steel （IF steel） from resin bonded MgO-SiC refractories is studied via a medium frequency induction furnace. Samples of IF steel were heated in MgO-SiC crucibles with mould flux cover at 1 600 ℃ for 180 min. The silicon contents of IF steel samples taken from the molten steel in every 30 min were examined and the refractories after heating were investigated by electron probe microanalysis （EPMA） with energy dispersive spectrometer （EDS）. The silicon content of steel rapidly increased in the first 90 min of beating, and then decreased because of the formation of liquid layer on the refractory. Liquid layer separated the liquid steel from the bulk refractory and stopped the pick-up of silicon. At the same time, desilication via oxygen through the liquid layer and flux started to reduce the silicon content of the liquid steel

关键词： MgO-SiC refractory silicon carbide silicon content steel

多次反射飞行时间质谱仪高性能矩形离子阱的研制

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分析化学 2025年第1期53卷 38-46页

作者：陈小霞任熠黄奇向大军李长伟洪义李磊黄正旭李梅徐经纬周振暨南大学环境与气候学院广东省麦思科学仪器创新研究院广州禾信仪器股份有限公司广东省大气污染在线源解析系统工程技术研究中心

作为新一代飞行时间质谱，多次反射飞行时间质谱（MR-TOF MS）因具有超高分辨率和快速分析能力在核物理、化学和生物学等领域得到了越来越广泛的应用。然而，MR-TOF MS的分析性能在很大程度上取决于进入质量分析器的离子团状态。本研究... 详细信息

作为新一代飞行时间质谱，多次反射飞行时间质谱（MR-TOF MS）因具有超高分辨率和快速分析能力在核物理、化学和生物学等领域得到了越来越广泛的应用。然而，MR-TOF MS的分析性能在很大程度上取决于进入质量分析器的离子团状态。本研究采用印刷电路板技术设计开发了一种矩形离子阱（RIT），以其作为离子收集和聚焦装置，可在离子进入质量分析器前对离子进行收集、冷却和抛出。相比于由两组平面电极构成的离子阱，此RIT的电压利用效率更高，可更充分实现离子的收集和聚焦。实验结果表明，此RIT的工作周期、离子通量和离子聚焦状态均满足MR-TOF质量分析器的要求，与其耦合后，离子经多次反射后的质量分辨率可达到1.5×10～5。

关键词：矩形离子阱离子传输质量范围质量分辨率多次反射飞行时间质谱

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Potential dependence in electrocatalysis:a theoretical perspective

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Science China Chemistry 2025年第1期68卷 21-25页

作者： Leyu Liu Zhaoming xia Zeyu Wang Yinjuan chen Hai xiao Department of Chemistry Tsinghua UniversityBeijing 100084China Fundamental Science Center of Rare Earths Ganjiang Innovation AcademyChinese Academy of SciencesGanzhou 341119China Key Laboratory of Advanced Catalytic Materials and Technology Advanced Catalysis and Green Manufacturing Collaborative Innovation CenterChangzhou UniversityChangzhou 213164China

Electrocatalysis is a key technology for the new energy era and sustainable development,serving as the interface for interconversion of electrical and chemical energies,which spans a wide spectrum of applications in sustainable energy and environmental *** reactions including electrochemical CO_(2)reduction reaction(eCO_(2)RR),hydrogen evolution reaction(HER),and oxygen evolution/reduction reactions(OER/ORR),hold essential promise for renewable energy technologies as well as complement the biogeochemical carbon and oxygen cycles.

关键词： spectrum interface Electrocatalysis

A novel supramolecular assembly based on nor-seco-cucurbit[10]uril for spermine sensing and artificial light-harvesting

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Chinese Chemical Letters 2025年第1期36卷 262-266页

作者： Ran Cen Yan-Yan Tang Li-xia chen Zhu Tao Xin xiao National Key Laboratory of Green Pesticide State Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationKey Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou ProvinceGuizhou UniversityGuiyang 550025China

A supramolecular assembly composed of perylene diimide derivative(PDI-nm)and nor-secocucurbit[10]uril(ns-Q[10])was *** excellent host-guest interaction between PDI-nm and nsQ[10]prevented the aggregation-caused quenching(ACQ)effect of PDI-nm,resulting in a luminescent *** addition of spermine to the PDI-nm/ns-Q[10]assembly restored the ACQ of PDI-nm due to the competitive binding of spermine to ns-Q[10],which released *** assembly based on this principle showed ultra-high sensitivity for the detection of spermine with a detection limit as low as7.84×10^(-7)mol/L in aqueous solution and 3.69×10^(-7)mol/L in plasma ***,an artificial light-harvesting system based on this assembly was proposed,benefiting from its good luminescent *** red(Ni R)functioned as an acceptor loaded into assembly,and a highly efficient energy transfer process occurred from PDI-nm/ns-Q[10]to Ni R,with an efficiency up to 87%.

关键词： Nor-seco-cucurbituril Perylene diimide derivative Spermine Light-harvesting

The Features and Patterns of Revision Process in English Learners＇ Writing

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Sino-US English Teaching 2013年第1期10卷 58-64页

作者： chen Min xia xiao-min China University of Political Sciences Beijing China

Revision is an important part of writing process but it often baffles the researchers due to the difficulties in recording the revision process of students. Based on a self-made questionnaire and the online record of the revision process, this study describes the English learners＇ revision behaviors and process in their second semester of a two-year writing course. The analysis indicates that the English learners hold a positive attitude towards revision and but passive in resorting to outside sources for help. The source of the feedback has a great influence on their motivation of revision. On the other hand, although they use all types of revision operations, they concentrate on surface changes and simple operations.

关键词： revision behaviors English learners writing

Synthesis of di-μ-oxo-tetra-(α-pentyloxy) tin(Ⅳ) phthalocyanine

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Chinese Chemical Letters 2008年第3期19卷 273-276页

作者： Yi Ru Peng Yu Hong Cao Pei Feng chen xiao xia Huang College of Chemistry ＆ Material Science Fujian Normal University Fuzhou 350007 China

Axially substituted tin phthalocyanines, namely dichloride-tetra-（α-pentyloxy） tin （Ⅳ） phthalocyanine 2, dihydroxy-tetra-（α-pentyloxy） tin （Ⅳ） phthalocyanine 3 and its dimmer di-μ-oxo-tetra-（α-pentyloxy） tin（Ⅳ） phthalocyanine 4 were synthesized. The catalytic effect of H2O-free CaCl2 in quinoline was used for condensation of dihydroxy tin phthalocyanine 3 to the cofacially array dimmer 4. Their structures were characterized by UV-vis, IR, elemental analysis, MS, as well as ^1HNMR spectroscopy.

关键词： Axially substituted tin (Ⅳ) phthalocyanine Dimmer Synthesis Characterization

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铸造用酚醛树脂粘结剂研究的进展

铸造 2005年第4期54卷 320-324页

作者：陈晓霞王力山东科技大学化学与环境工程学院山东青岛266510

热固性酚醛树脂是树脂砂铸造生产中重要的树脂粘结剂之一。本文中,从铸造用酚醛树脂的种类、性能特征、树脂的合成及固化、结构分析、目前铸造用树脂中存在的主要问题及发展方向等方面概述了铸造用酚醛树脂粘结剂研究的进展。

关键词：酚醛树脂粘结剂铸造

Inexact proximal gradient algorithm with random reshuffling for nonsmooth optimization

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Science China(Information Sciences) 2025年第1期68卷 219-237页

作者： xia JIANG Yanyan FANG xianlin ZENG Jian SUN Jie chen National Key Lab of Autonomous Intelligent Unmanned Systems School of AutomationBeijing Institute of Technology Beijing Institute of Technology Chongqing Innovation Center School of Electronic and Information Engineering Tongji University

Proximal gradient algorithms are popularly implemented to achieve convex optimization with nonsmooth regularization. Obtaining the exact solution of the proximal operator for nonsmooth regularization is challenging because errors exist in the computation of the gradient; consequently, the design and application of inexact proximal gradient algorithms have attracted considerable attention from researchers. This paper proposes computationally efficient basic and inexact proximal gradient descent algorithms with random reshuffling. The proposed stochastic algorithms take randomly reshuffled data to perform successive gradient descents and implement only one proximal operator after all data pass through. We prove the convergence results of the proposed proximal gradient algorithms under the sampling-without-replacement reshuffling *** computational errors exist in gradients and proximal operations, the proposed inexact proximal gradient algorithms can converge to an optimal solution neighborhood. Finally, we apply the proposed algorithms to compressed sensing and compare their efficiency with some popular algorithms.

关键词： proximal operator random reshuffling inexact computation compressed sensing nonsmooth optimization

Analysis on Joyce Kilmer's“Trees”

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张家口职业技术学院学报 2001年第1期14卷 28-30页

作者：陈晓霞张家口广播电视大学河北张家口 075000

English poetry is particular about rhythm and *** author here is trying to use the knowledge of prosody to give an analysis of "Trees",a poem written by American poet Joyce Kilmer.

关键词：韵律学美国文学研究诗歌 "树" 乔伊斯·开默韵律节奏