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A Test Method for Torsion Strength of Refractory Materials at Elevated Temperatures

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China's Refractories 2018年第3期27卷 28-31页

作者： ZHU Qingyou GE Shan yin yucheng LIU Zhiqiang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology

New apparatus for the determination of torsion strength of refractory materials at elevated temperatures has been developed in this work. With the employment of heating wire and induction heating unit,this device can carry out torsion strength test at high temperatures at the heating rate ranging from 10 ℃/min to 200 ℃/*** strength of high alumina brick,magnesia brick and Si3 N4 bonded SiC brick has been tested at different heating rates of 10 ℃/min,100 ℃/min and 200℃/min,separately. Results indicate that,for high alumina brick,the tested torsion strength at the heating rate of 10 ℃/min is very close to that at 100 ℃/min,but very different from that at 200 ℃/min. The tested torsion strength of magnesia brick at different heating rates differs greatly,while that of Si3 N4 bonded SiC brick is similar. This suggests that the structure of refractory materials with poor thermal shock resistance might be damaged when the heating rate of 200 ℃/min was applied,but the heating rate of 100 ℃/min is possible for a lot of refractory products. At fast heating rates,it takes only1 h to finish a test at elevated temperatures,thus saving a lot of time and energy.

关键词： torsion strength heating rate refractory materials local heating

Effect of TiO_2 on the Sinterability and Microstructure of Mullite Sythesized from Al(OH)_3 and SiO_2

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China's Refractories 2006年第2期15卷 3-6页

作者： LIANG Yonghe yin yucheng WU Yunyun WANG Jibao The Hubei Province Key Laboratory of Refractory Ceramics Ministry-Province Jointly Constructed Cultivation Base for State Key Laboratory Hubei Wuhan 430081

Using analytical pure Al（ OH）3 , SiO2 , TiO2 as raw materials, effect of TiO2 on the sinterability and microstructure of mullite synthesized from Al （ OH）3 and SiO2 was investigated in this paper by XRD , SEM and EPAX. Results show that TiO2 can promote the sintering property when the amount is below 6%, the sinterability of samples becomes better with the increase of the amount of TiO2, microstructure of samples densify gradually, and the best effect can be achieved when the amount of TiO2 is 6%. It was shown by XRD analysis that no Al2TiO5 present when the amount of TiO2 is below 6%, TiO2 existed in the form of solid-solution and glass phase; When the amount of TiO2 is up to 6%, the sinterability of samples becomes worse with the increase of TiO2 added, microstructure of samples began to loosen, Al2TiO5 can be observed in samples and its amount increase with the increase of TiO2.

关键词： Mullite sinterability TiO2 Microstructure

Two types of coumarins-specific enzymes complete the last missing steps in pyran- and furanocoumarins biosynthesis

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Acta Pharmaceutica Sinica B 2024年第2期14卷 869-880页

作者： yucheng Zhao Yuedong He Liangliang Han Libo Zhang Yuanzheng Xia Fucheng yin Xiaobing Wang Deqing Zhao Sheng Xu Fei Qiao Yibei Xiao Lingyi Kong Department of Resources Science of Traditional Chinese Medicines School of Traditional Chinese Pharmacyand State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China College of Bioscience and Biotechnology Hunan Agricultural UniversityChangsha 410128China Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines Department of Natural Medicinal ChemistryChina Pharmaceutical UniversityNanjing 210009China Key Laboratory of Crop Gene Resources and Germplasm Enhancement in Southern China Ministry of AgricultureTropical Crops Genetic Resources InstituteChinese Academy of Tropical Agricultural SciencesHaikou 517317China Institute of Botany Jiangsu Province and Chinese Academy of SciencesNanjing 210014China Department of Pharmacology School of Pharmacyand State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China

Pyran-and furanocoumarins are key representatives of tetrahydropyrans and tetrahydrofurans,respectively,exhibiting diverse physiological and medical ***,the biosynthetic mechanisms for their core structures remain poorly *** we combined multiomics analyses of biosynthetic enzymes in Peucedanum praeruptorum and in vitro functional verification and identified two types of key enzymes critical for pyran and furan ring biosynthesis in *** included three distinct *** prenyltransferases(PpPT1e3)responsible for the prenylation of the simple coumarin skeleton 7 into linear or angular precursors,and two novel CYP450 cyclases(PpDC and PpOC)crucial for the cyclization of the linear/angular precursors into either tetrahydropyran or tetrahydrofuran *** analyses of cyclases indicated that acid/base-assisted epoxide ring opening contributed to the enzyme-catalyzed tetrahydropyran and tetrahydrofuran ring *** possible acid/base-assisted catalytic mechanisms of the identified cyclases were theoretically investigated and assessed using site-specific *** identified two possible acidic amino acids Glu303 in PpDC and Asp301 in PpOC as vital in the catalytic *** study provides new enzymatic tools in the epoxide formation/epoxide-opening mediated cascade reaction and exemplifies how plants become chemically diverse in terms of enzyme function and catalytic process.

关键词： Tetrahydropyrans Tetrahydrofurans Baldwin rules Coumarins CYP450cyclase

Effects of binder addition on properties of environmental-friendly tap-hole clay

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Effects of binder addition on properties of environmental-fr...

组合式Forsus矫治器对安氏Ⅱ~1错牙弓及颅面硬组织的影响

第十九届全国高技术陶瓷学术年会

作者： Wang Linyun Liang Yonghe 聂建华 yin yucheng Cai Manfei The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology

An environmental-friendly tap-hole clay was developed using resin as binder,and the effects of pitch addition on tap-hole clay have been *** chromatography and mass spectrometry(GC-MS)analysis results show this tap-hole clay were free of no benzo(a)pyrene(Ba P).The phase composition and micro-structural features treating at various temperatures were investigated by X-ray diffraction,scanning electron microscopy,coupled with energy dispersive X-ray *** the increase of binder addition,marshall value,bulk density,cold crushing strength,hot modulus of rupture and slag resistance decreased,while apparent porosity increased which has close relationship with the evaporation of resin ***,this also caused the significant linear shrinkage of tap-hole ***,volumetric expansion of mullite formed through decomposition of kyanite or in suit reaction between AlO and Si O2,negated some shrinkage at temperature up to1200-1400℃.Oxidation resistance can be improved by increasing the resin *** is suggested that 17 wt%of resin is helpful to improve the properties of tap-hole clay.

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实用口腔医学杂志 2010年第1期26卷 67-70页

作者：尹玉承兰泽栋深圳市第五人民医院口腔中心 518001 广州医学院口腔医院正畸科

目的:探讨组合式Forsus矫治器对青少年生长发育期安氏Ⅱ1错的矫治效果。方法:选择13例处于生长发育前期及高峰期的安氏Ⅱ1错患者,应用组合式Forsus矫治器进行平均5.5个月的矫治,通过头影测量评判矫治效果。结果:13例患者尖牙及磨牙... 详细信息

目的:探讨组合式Forsus矫治器对青少年生长发育期安氏Ⅱ1错的矫治效果。方法:选择13例处于生长发育前期及高峰期的安氏Ⅱ1错患者,应用组合式Forsus矫治器进行平均5.5个月的矫治,通过头影测量评判矫治效果。结果:13例患者尖牙及磨牙关系均达到Ⅰ类或偏近中关系,下颌后缩,面型明显改善。结论:组合式Forsus矫治器可以进行早期功能矫治,能够改善Ⅱ类面型,减少二期固定矫治的难度、提高矫治效果。

关键词：组合式Forsus矫治器安氏Ⅱ类1分类错 下颌后缩

Influence of silicon oxynitride on slag resistance and inoxidizability of Al2O3-SiC-C bricks

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Influence of silicon oxynitride on slag resistance and inoxi...

第十九届全国高技术陶瓷学术年会

作者： Zhang Guotan 聂建华 Wen Jin Liang Yonghe yin yucheng Zhang Han The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology

In this paper, silicon oxynitride prepared in laboratory was added in shaped refractory material of AlO-Si C-C to improve its slag resistance and oxidation resistance. Optimum adding quantity of silicon oxynitride powder also has been studied in this paper. The results show that the oxidation resistance and slag resistance of AlO-Si C-C shaped refractory were better while SiNO addition amount was 2% and 3% respectively;adding suitable amount of SiNO can promote to generate vitreous phases in the pores of oxide layers of AlO-Si C-C shaped refractory, thus blocking pores and preventing the spread of the oxygen to oxide test specimens;adding suitable amount of SiNO into AlO-Si C-C shaped refractory can promote to produce more silicon oxide into the slag, therefore improving the viscosity of slag and weakening the slag erosion and penetration to the samples.

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高炉炭砖气孔特性的表征与评价

炼铁 2008年第1期27卷 47-49页

作者：葛山尹玉成武汉科技大学

对炭砖气孔特性指标的定义、测量方法及其影响因素和测量设备存在的问题进行了阐述,并对目前普遍采用的表征这些指标的方法进行了比较和评价。

关键词：高炉炭砖气孔特性测量

Hydrogen and nitrogen absorption properties of Ce-added Zr_(2)(Fe_(1-x)Ni_(x)) alloys

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Journal of Rare Earths 2024年第6期42卷 1136-1141,I0005页

作者： Kai yin Xiaopeng Liu State Key Laboratory of Advanced Materials for Smart Sensing GRINM Group Co.Ltd.Beijing10088China GRIMAT Engineering Institute Co. Ltd.Beijing101407China General Research Institute of Nonferrous Metals Beijing100088China

To improve the nitriding resistance of Zr_(2)Fe alloy,the Ce-added Zr_(2)(Fe_(1-x)Ni_(x))(x=0,0.15,0.3,0.5)alloys were prepared by magnetic levitation melting *** effects of Ni substitution for Fe on the phase structure,hydrogen and nitrogen absorption properties of the alloys were investigated by X-ray diffraction,scanning electron microscopy and p-c isotherm *** experimental results show that Ni substitution can effectively inhibit the formation of both α-Zr and ZrFe_(2) phases and promote the formation of C16 structure Zr_(2)(Fe,Ni)phase,causing Ni-substituted alloys to exhibit low nitrogen absorption rate and *** 623 K under 0.5 MPa nitrogen pressure,the nitrogen absorption capacity of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy reaches to 0.8 mL/g,much lower than that of Zr_(2)Fe alloy(1.5 mL/g).Ni substitution decreases the crystal cell volume of the C_(16)Zr_(2)(Fe,Ni)phase,resulting in an increase in the hydrogen absorption equilibrium *** 623 K under 0.05 MPa hydrogen pressure,the hydrogen absorption capacity decreases from 1.46 wt%of Zr_(2)Fe alloy to 1.41 wt%of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy.

关键词： Zr_(2)Fe alloy Ce Pressure-composition isotherm Hydrogen absorption Nitrogen absorption Rare earths

Rational surface charge engineering of haloalkane dehalogenase for boosting the enzymatic performance in organic solvent solutions

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Chinese Journal of Chemical Engineering 2024年第1期65卷 276-285页

作者： yin Wu Yan Sun Department of Biochemical Engineering School of Chemical Engineering and Technology and Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education)Tianjin UniversityTianjin 300350China

Biocatalysis in organic solvents(OSs)has numerous important applications,but native enzymes in OSs often exhibit limited catalytic ***,we proposed a computation-aided surface charge engineering strategy to improve the catalytic performance of haloalkane dehalogenase DhaA in OSs based on the energetic analysis of substrate binding to the DhaA *** variants with enhanced OS resistance were obtained by replacing negative charged residues on the surface with positive charged residue(Arg).Particularly,a four-substitution variant E16R/E93R/E121R/E257R exhibited the best catalytic performance(five-fold improvement in OS resistance and seven-fold half-life increase in 40%(vol)dimethylsulfoxide).As a result,the overall catalytic performance of the variant could be at least 26 times higher than the wild-type *** spectroscopy and molecular dynamics simulation studies revealed that the residue substitution mainly enhanced OS resistance from four aspects:(a)improved the overall structural stability,(b)increased the hydrophobicity of the local microenvironment around the catalytic triad,(c)enriched the hydrophobic substrate around the enzyme molecule,and(d)lowered the contact frequency between OS molecules and the catalytic *** findings validate that computationaided surface charge engineering is an effective and ingenious rational strategy for tailoring enzyme performance in OSs.

关键词： Surface charge engineering Organic solvent resistance Molecular dynamics simulation Haloalkane dehalogenase