With TiCl4/MgCl2(Ti)and Al(i-Bu)3(Al)as catalysts,the thermoplastic copolymer of 1-butene(Bt)and 1-hexene(He)was synthesized successfully.The effects of Bt/He,Ti/(He+Bt),Al/Ti,temperature and reaction time on conversi...With TiCl4/MgCl2(Ti)and Al(i-Bu)3(Al)as catalysts,the thermoplastic copolymer of 1-butene(Bt)and 1-hexene(He)was synthesized successfully.The effects of Bt/He,Ti/(He+Bt),Al/Ti,temperature and reaction time on conversion,catalyst efficiency(CE),intrinsic viscosity([g])and insoluble content were studied.The copolymer was analyzed with Fourier transform-infrared(FTIR)and nuclear magnetic resonance(1H-NMR).Results showed that the optimal polymerization conditions were:He/Bt=0.25,temperature 40℃–50℃,Al/Ti=400–500,Ti/(Bt+He)=3x10-5-4x10-5,time 4 h.Intrinsic viscosity was found to increase with increasing Ti/(Bt+He)and decreasing Al/Ti and polymerization temperature.When the molar content of He,Al/Ti and polymerization temperature increased,the insoluble content in CH2Cl2 of copolymers decreased.When Ti/(Bt+He)and reaction time increased,the insoluble con-tent in CH2Cl2 of copolymers also increased.The crystal-lization and stereoregularity of poly(1-butene)decreased with the addition of He.展开更多
Due to its highly favorable physical and chemical properties,titanium and titanium alloy are widely used in a variety of industries.Because of the low output of a single batch,plate cold rolling without tension is the...Due to its highly favorable physical and chemical properties,titanium and titanium alloy are widely used in a variety of industries.Because of the low output of a single batch,plate cold rolling without tension is the most common rolling production method for titanium alloy.This method is lack of on-line thickness closed-loop control,with carefully thickness setting models for precision.A set of high-precision thickness setting models are proposed to suit the production method.Because of frequent variations in rolling specification,a model structural for the combination of analytical models and statistical models is adopted to replace the traditional self-learning method.The deformation resistance and friction factor,the primary factors which affect model precision,are considered as the objectives of statistical modeling.Firstly,the coefficient fitting of deformation resistance analytical model based on over-determined equations set is adopted.Additionally,a support vector machine（SVM）is applied to the modeling of the deformation resistance and friction factor.The setting models are applied to a 1450 plate-coiling mill for titanium alloy plate rolling,and then thickness precision is found consistently to be within 3%,exceeding the precision of traditional setting models with a self-learning method based on a large number of stable rolling data.Excellent application performance is obtained.The proposed research provides a set of high-precision thickness setting models which are well adapted to the characteristics of titanium alloy plate cold rolling without tension.展开更多
The corrosion and weaker interaction with metal catalysts of common carbon supports during electrocatalysis push the development of alternative supports materials. Titanium oxide-based materials have been widely explo...The corrosion and weaker interaction with metal catalysts of common carbon supports during electrocatalysis push the development of alternative supports materials. Titanium oxide-based materials have been widely explored as electrocatalysts supports in consideration of their chemical stability, strong interactions with metal catalyst and wider applications in electrocatalytic reactions as well as the improved electronic conductivity. This review summarizes recent research advances in engineering titanium oxide-based supports for the catalysts in electrocatalysis field to provide guidance for designing high performance non-carbon supported electrocatalysts. Typically, the titanium oxide-based supports are classified into shaped TiO_(2), doped TiO_(2), titanium suboxide and TiO_(2)-carbon composites according to the modification methods and corresponding preparation methods. Then the engineering strategies and electrocatalytic applications are discussed in detail. Finally, the challenges, future research directions and perspectives of titanium oxide-based supports for electrocatalysis are presented for practical applications.展开更多
基金supported by the National High-Tech Research and Development Program of China(863 Program)(Grant No.2006AA03Z546).
文摘With TiCl4/MgCl2(Ti)and Al(i-Bu)3(Al)as catalysts,the thermoplastic copolymer of 1-butene(Bt)and 1-hexene(He)was synthesized successfully.The effects of Bt/He,Ti/(He+Bt),Al/Ti,temperature and reaction time on conversion,catalyst efficiency(CE),intrinsic viscosity([g])and insoluble content were studied.The copolymer was analyzed with Fourier transform-infrared(FTIR)and nuclear magnetic resonance(1H-NMR).Results showed that the optimal polymerization conditions were:He/Bt=0.25,temperature 40℃–50℃,Al/Ti=400–500,Ti/(Bt+He)=3x10-5-4x10-5,time 4 h.Intrinsic viscosity was found to increase with increasing Ti/(Bt+He)and decreasing Al/Ti and polymerization temperature.When the molar content of He,Al/Ti and polymerization temperature increased,the insoluble content in CH2Cl2 of copolymers decreased.When Ti/(Bt+He)and reaction time increased,the insoluble con-tent in CH2Cl2 of copolymers also increased.The crystal-lization and stereoregularity of poly(1-butene)decreased with the addition of He.
基金Supported by National Natural Science Foundation of China(Grant No.51304017)National Key Technology R&D Program of the 12th Five-year Plan of China(Grant Nos.2012BAF04B02,2011BAE23B04)Fundamental Research Funds for Central Universities,China(Grant No.FRF-SD-12-013B)
文摘Due to its highly favorable physical and chemical properties,titanium and titanium alloy are widely used in a variety of industries.Because of the low output of a single batch,plate cold rolling without tension is the most common rolling production method for titanium alloy.This method is lack of on-line thickness closed-loop control,with carefully thickness setting models for precision.A set of high-precision thickness setting models are proposed to suit the production method.Because of frequent variations in rolling specification,a model structural for the combination of analytical models and statistical models is adopted to replace the traditional self-learning method.The deformation resistance and friction factor,the primary factors which affect model precision,are considered as the objectives of statistical modeling.Firstly,the coefficient fitting of deformation resistance analytical model based on over-determined equations set is adopted.Additionally,a support vector machine（SVM）is applied to the modeling of the deformation resistance and friction factor.The setting models are applied to a 1450 plate-coiling mill for titanium alloy plate rolling,and then thickness precision is found consistently to be within 3%,exceeding the precision of traditional setting models with a self-learning method based on a large number of stable rolling data.Excellent application performance is obtained.The proposed research provides a set of high-precision thickness setting models which are well adapted to the characteristics of titanium alloy plate cold rolling without tension.
基金supported by the National Natural Science Foundation of China(91963109)the Innovation Research Funds of the Huazhong University of Science and Technology(2019kfyR CPY100)。
文摘The corrosion and weaker interaction with metal catalysts of common carbon supports during electrocatalysis push the development of alternative supports materials. Titanium oxide-based materials have been widely explored as electrocatalysts supports in consideration of their chemical stability, strong interactions with metal catalyst and wider applications in electrocatalytic reactions as well as the improved electronic conductivity. This review summarizes recent research advances in engineering titanium oxide-based supports for the catalysts in electrocatalysis field to provide guidance for designing high performance non-carbon supported electrocatalysts. Typically, the titanium oxide-based supports are classified into shaped TiO_(2), doped TiO_(2), titanium suboxide and TiO_(2)-carbon composites according to the modification methods and corresponding preparation methods. Then the engineering strategies and electrocatalytic applications are discussed in detail. Finally, the challenges, future research directions and perspectives of titanium oxide-based supports for electrocatalysis are presented for practical applications.
