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Selective hydrogenation of acetylene on SiO_2-supported Ni-Ga alloy and intermetallic compound

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Journal of Energy Chemistry 2019年第2期28卷 40-49页

作者： Lei Wang fengxu li Yanjun Chen Jixiang Chen Tianjin Key Laboratory of Applied Catalysis Science and Technology Department of Catalysis Science and EngineeringSchool of Chemical Engineering and TechnologyTianjin University

Ni/Si O_2 and bimetallic Ni_xGa/SiO_2 catalysts with different Ni/Ga atomic ratios(x = 10～2) were investigated for the selective hydrogenation of *** was found that Ni_xGa/SiO_2 showed higher selectivity to ethylene than Ni/Si O_*** is attributed to the formation Ni-Ga alloy and Ni3 Ga intermetallic compound(IMC) where there was a charge transfer from Ga to Ni,which is favorable for reducing the adsorption strength and amount of ethylene on Ni *** a result,the over-hydrogenation,the C–C bond hydrogenolysis and the polymerization were suppressed,and subsequently the selectivity to ethylene was *** the decrease of Ni/Ga atomic ratio,the activity and stability of the Ni_xGa/SiO_2 catalysts increased first and then decreased,while the ethylene selectivity tended to ***_5 Ga/SiO_2 exhibited the best *** the conditions of 180 °C,0.1 MPa,and a reactant(1.0 vol% acetylene,5.0 vol% H_2 and 94 vol% N_2) with the space velocity of 36,000 m L h^(-1) g^(-1),the acetylene conversion maintained at 100% on Ni_5 Ga/SiO_2 during 120 h time on stream and the selectivity to ethylene was 75%～81%after reaction for 68 *** was also found that the formation of Ni-Ga alloy and Ni_3 Ga IMC suppressed the incorporation of carbon to form NiCx,subsequently enhancing the catalyst ***,with increasing the Ga content,the catalyst acid amount and strength tended to increase,which promoted the polymerization and carbon deposition and so the catalyst deactivation.

关键词： Selective hydrogenation Acetylene Ni-Ga alloy Ni3Ga intermetallic compound

商业街区景观中历史文化传承与发展——以南京老门东为例

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装饰 2020年第10期 124-125页

作者：祝遵凌李丰旭南京林业大学艺术设计学院

商业街区是传统历史文化的承载体现,最能反映该地区的地域文化,它体现了该地区的商业文化、经济发展和历史演变的兴衰交替。本文以老门东为例,分析了老门东内部景观设计中历史文脉传承与发展的现状,并提出历史文脉表达与传承的原则。

关键词：商业街区历史街区文化传承历史文脉

Research on control algorithm of intelligent valve positioner based on parameter self-tuning

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Research on control algorithm of intelligent valve positione...

Development of intelligent pneumatic control valve and Derformance testing device

第三十九届中国控制会议

作者： Qian Cheng Zhifeng liu Aipeng Jiang Enhui Jiang Yangjian Xiao fengxu li Jiaji Jiang School of Automation Hangzhou Dianzi University

Pneumatic valve positioner is widely used in chemical industry, energy, oil and gas, water treatment, paper industry and other industrial fields. The type of foreign valve positioner has been transferred from mechanical and electronic to intelligent electronic. However, the domestic research on valve positioner research started late, the technology is relatively backward, the failure rate is high. The main reason that affects the performance of domestic valve positioners is due to the immature control algorithm. Based on the analysis of the traditional five-step switch control algorithm, an improved control algorithm and a new parameter auto-tuning method are proposed. All control parameters in the improved control algorithm are obtained by self-tuning, which improves the universality of the algorithm. The parameter self-tuning method can automatically identify the stroke type, end position, maximum overshoot, optimal PWM duty ratio of different valve positions and other parameters, which provides the basis for the control parameter selection of the improved control algorithm. The control algorithm was implemented and verified with the help of an experimental bench. The experimental results show that the improved control algorithm not only greatly reduces the valve position adjustment time, but also avoids the overshoot phenomenon in the whole stroke range.

关键词： Intelligent valve positioner Five step switch control algorithm Parameter self-tuning optimal PWM overshoot

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Development of intelligent pneumatic control valve and Derfo...

安装偏差对胶合木梁柱植筋节点受弯承载力的影响

第40届中国控制会议

作者： Jiang Jiaji Jiang Aipeng li fengxu Cheng Qian Zhang Bo Wang Haodong lin Tong School of Automation Hangzhou Dianzi University

With the improvem ent of modern industrial automation,regulating valv e s are increasingly widely used in metallurgy,energy,chemical,petroleum,military,water conservancy and other industrial sectors,playing an irreplaceable *** present,most domestic regulating valve enterprises adopt vernier calipers or dial gauge positioning test when calibrating the position accuracy index,which is complicated with low precision calculation and low repeatability of detection *** this paper,design of the device of the traditional test method by high precision displacement sensor calibration and optimization,has realized the remote control valve opening and the regulating valve position precision index and intelligent positioner to test the intelligent control algorithm,and the analysis of the merits of the intelligent positioner control algorithm both at home and abroad,greatly promote the regulator assembly testing efficiency,improve the quality of the *** the same time,a life test is designed to determin e whetherthe position a ccura cy of the regula tingvalv e will change after several step *** result s show that the control effect and position precision of the control valve will be changed after a large number of valve position movements.

关键词： Control valve Position accuracy Positioner Control algorithm Intelligence Step

来源： cnki会议评论

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土木与环境工程学报（中英文） 2024年第2期46卷 138-145页

作者：唐秋霞李军郭峰旭解选本王燕青岛理工大学土木工程学院山东青岛266033 重庆长厦安基建筑设计有限公司青岛分公司山东青岛266061 青岛市即墨区古城发展服务中心山东青岛266200

胶合木植筋节点在加工和安装时通常会存在些许缺陷和误差,且植筋节点的设计和施工目前尚无标准可循。为了研究含加工缺陷在内的安装偏差对该类节点受弯承载力的影响,明确安装偏差的允许范围,基于理论计算方法初步校核所设计节点的梁端... 详细信息

胶合木植筋节点在加工和安装时通常会存在些许缺陷和误差,且植筋节点的设计和施工目前尚无标准可循。为了研究含加工缺陷在内的安装偏差对该类节点受弯承载力的影响,明确安装偏差的允许范围,基于理论计算方法初步校核所设计节点的梁端抗弯承载力,然后进行有、无安装偏差节点的有限元分析,并与有安装偏差的试验结果进行对比,运用考虑胶层开裂的有限元分析方法确定安装偏差限值。结果表明:有安装偏差节点的梁端抗弯承载力有所下降;试验中试件的破坏形态主要为植入钢筋屈服、植筋孔洞周围木材破坏及木柱顺纹方向开裂;有限元分析时考虑安装偏差和胶层开裂,则分析结果与试验吻合度较高;相对于通常预留间隙10 mm的节点模型,安装偏差控制在10~25 mm以内时,受弯承载力的降低幅度低于5%。

关键词：胶合木结构植筋节点梁柱节点循环反复荷载安装偏差

过程取向的小学数体课程整合:内涵、价值与实施

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上饶师范学院学报 2021年第3期41卷 6-13页

作者：李丰旭江苏师范大学教育科学学院江苏徐州221116

过程取向的小学数体课程整合从学生“学”的视角出发,以过程为取向,将小学数学课程与体育课程相整合,以跨学科的方式实现国家课程校本化。这一整合课程的基本价值取向是通过过程教学培养学生具有较强的数学感知能力和数学学科核心素养,... 详细信息

过程取向的小学数体课程整合从学生“学”的视角出发,以过程为取向,将小学数学课程与体育课程相整合,以跨学科的方式实现国家课程校本化。这一整合课程的基本价值取向是通过过程教学培养学生具有较强的数学感知能力和数学学科核心素养,旨在通过各种有组织有目的的身体活动,解决数学过程教学的空有其表问题与学生感知能力普遍较差问题,引导学生在增强体魄的同时产生具身认知,从而积累数学活动经验,使其数学学科核心素养在过程教学中自然生成。过程取向的小学数体整合课程建立以核心素养为取向的课程目标、以主题为框架的课程内容、以“电子教学计划表”为动态指导的课程实施、以形成性和发展性为理念的课程评价,可为小学校本课程的开发提供借鉴。

关键词：小学数学课程体育课程课程整合过程取向具身认知

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对苯二甲酸加氢合成对苯二甲醇

精细石油化工 2017年第4期34卷 24-27页

作者：宋义伟纪军田鹤李凤绪中国石油工程建设有限公司华北分公司河北任丘062552

采用浸渍法制备Ru-Sn-B/Al_2O_3催化剂,应用于对苯二甲酸加氢反应制备对苯二甲醇。考察了催化剂制备方法、加氢反应温度和反应压力以及催化剂用量对加氢反应的影响。实验结果表明,合适的催化剂制备方法是采用Ru、Sn共浸渍后由NaBH_4还... 详细信息

采用浸渍法制备Ru-Sn-B/Al_2O_3催化剂,应用于对苯二甲酸加氢反应制备对苯二甲醇。考察了催化剂制备方法、加氢反应温度和反应压力以及催化剂用量对加氢反应的影响。实验结果表明,合适的催化剂制备方法是采用Ru、Sn共浸渍后由NaBH_4还原制备,优化的反应条件是:m(催化剂)∶m(对苯二甲酸)∶m(H_2O)=1∶4.0∶40,反应温度230℃,反应压力10.0 MPa,反应5.0h,对苯二甲酸转化率达到100%,对苯二甲醇摩尔收率为88.9%。催化剂使用寿命考察结果表明,Ru-Sn-B/Al2O3催化剂具有很好的稳定性。

关键词：对苯二甲醇催化加氢对苯二甲酸

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劣质渣油热改质与供氢热改质

石油学报（石油加工） 2014年第3期30卷 439-445页

作者：王齐王宗贤庄士成李凤绪郭磊郭爱军中国石油大学化学工程学院重质油国家重点实验室山东青岛266580

分别采用釜式反应法和热重分析法对委内瑞拉减压渣油(VR)进行单独热改质和供氢热改质研究,探讨所选富芳馏分作为工业供氢剂的可行性,及其对渣油热转化产物分布与生成油产物安定性的影响。结果表明,与热改质相比,供氢热改质所选供氢剂可... 详细信息

分别采用釜式反应法和热重分析法对委内瑞拉减压渣油(VR)进行单独热改质和供氢热改质研究,探讨所选富芳馏分作为工业供氢剂的可行性,及其对渣油热转化产物分布与生成油产物安定性的影响。结果表明,与热改质相比,供氢热改质所选供氢剂可以减缓VR的热失重速率,使VR热改质反应更温和,抑制了相分离,改善了生成油的安定性;供氢热改质能够承受更高反应苛刻度;在生成油安定性均为二级时,供氢热改质使产物总产率提高约4百分点,其中气体产率(质量分数,下同)、馏分油产率、轻蜡油产率分别提高0.50、1.85、1.66百分点。

关键词：供氢剂热改质劣质渣油安定性热重分析

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停车库火灾自动报警系统的设计

智能建筑电气技术 2007年第6期1卷 34-36页

作者：李凤栩中国建筑标准设计研究院

笔者根据自己的设计实践,阐述了停车库火灾自动报警及消防联动控制系统设计方面的思路和技术要求。

关键词：停车库火灾自动报警消防联动控制