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Development of New Generation Catalysts for Selective Hydrodesulfurization of FCC Naphtha

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China Petroleum Processing & Petrochemical Technology 2009年第1期11卷 19-23页

作者： Chu Yang li Mingfeng li huifeng Qu Jinhua Nie Hong li Dadong (Research Institute of Petroleum Processing, SINOPEC Corp., Beijing 100083) Research Institute of Petroleum Processing SINOPEC Corp. Beijing 100083 China

The influence of active metal components of catalyst, additives and catalyst preparation method on the reactivity of catalyst for selective hydrodesulfurization (HDS) of FCC naphtha was investigated, and the RSDS-21 catalyst with high HDS performance and the RSDS-22 catalyst with high selectivity were developed by RIPP. The composite loading of a new series of catalysts for selective HDS of FCC gasoline has demonstrated excellent desulfurization activity and selectivity and can under conventional hydrotreating conditions manufacture clean gasoline product meeting the national IV emission standard and the Euro V emission standard with less loss in antiknock index. The finalized new series of FCC catalysts upon being adopted for selective HDS of FCC naphtha have good adaptability to different feedstocks along with good stability.

关键词： FCC gasoline selective hydrogenation hydrodesulfurization catalyst anti-knock index

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日粮添加益生菌改善乳鸽肠道健康和生产性能

山西农业大学学报（自然科学版） 2024年第2期44卷 71-79页

作者：董元洋韩鹏敏郑钰崎苗志强韩苗苗宋献艺张俊珍麻慧王政李慧锋李建慧山西农业大学动物科学学院山西晋中030801 中国农业科学院北京畜牧兽医研究所北京100193 山西农业大学生命科学学院山西晋中030801

[目的]本文旨在研究在日粮中添加屎肠球菌和枯草芽孢杆菌对乳鸽生长性能的改善效果,及是否通过调节肠道形态、消化酶活性及肠道微生物区系,发挥促生产作用。[方法]试验选取240只12日龄、体重接近的健康白羽王鸽,随机分成4组,分别为对照... 详细信息

[目的]本文旨在研究在日粮中添加屎肠球菌和枯草芽孢杆菌对乳鸽生长性能的改善效果,及是否通过调节肠道形态、消化酶活性及肠道微生物区系,发挥促生产作用。[方法]试验选取240只12日龄、体重接近的健康白羽王鸽,随机分成4组,分别为对照组、屎肠球菌组、枯草芽孢杆菌组、屎肠球菌与枯草芽孢杆菌混合添加组。于试验第16天(28日龄)测定生产性能并进行屠宰采样,测定十二指肠、空肠、回肠肠道形态,十二指肠内容物消化酶活性和结直肠微生物区系等指标。[结果]与对照组相比,屎肠球菌处理组显著提高12~28 d龄平均日增重。与对照组相比,屎肠球菌处理可显著提高十二指肠胰蛋白酶活性,枯草芽孢杆菌及混合处理添加可显著提高十二指肠中淀粉酶活性(P<0.05)。益生菌单独或混合添加处理组乳鸽的十二指肠、空肠、回肠绒毛高度显著升高,均显著提高空肠、回肠的绒毛高度与隐窝深度比值(P<0.05);16S rRNA分析结直肠微生物区系结果表明,单独或混合添加屎肠球菌、枯草芽孢杆菌可提高结直肠奇异菌属(Atopobium)、分节丝状菌(Candidatus Arthromitus)、芽孢杆菌(Bacillus)丰度,以上益生菌具有肠道改善功能。[结论]屎肠球菌和枯草芽孢杆菌可改善乳鸽肠道形态,提高消化酶活性,增加肠道有益菌数量,进而促进乳鸽生长性能,具有良好的生产应用潜力。

关键词：益生菌乳鸽肠道健康生产性能

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ESTIMATION FOR THE ASYMPTOTIC BEHAVIOR OF THE DELAYED COMPETITION MODEL

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Journal of Partial Differential Equations 2008年第4期21卷 289-302页

作者： li huifeng Wang Jinliang College of Science Qingdao Technological University Qingdao 266033 China

In ecological dynamic systems, the competition between species is a very universal phenomenon, which can be described by the well-known Volterra-Lotka model in a diffusion form. Noticing that the living space usually changes in a seasonal manner and the population development of the species may also undergo time-delay im- pact, a developed form of this model is investigated in this article. The main approaches employed here are the upper-lower solution method and the energy-estimate technique. The results show that whether the species may sustain survival or not depends on the relations among the birth rate, the death rate, the competition rate, the diffusivity and the time delay. For the survival case, the population evolutions of the two species may appear asymptotic periodicity with distinct upper bound and this bound depends heavily on the time delay. These results can be also checked by the intuitionistic numerical simulations.

关键词： Volterra-Lotka diffusion periodic asymptotic time delay.

Effect of yttrium and manganese addition on catalytic soot combustion activity and anti-high-temperature stability of CeO_(2) catalyst

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Journal of Rare Earths 2024年第2期42卷 334-344,I0004页

作者： Yi Zhu Xingyu liu Wei Shi Jia li Changbing Ye Ruimei Fang huifeng Zhu Shanhu Chen li Lan College of Chemistry Biology and Environment Yuxi Normal UniversityYuxi 653100China Institute of Biology and Environmental Engineering Yuxi Normal UniversityYuxi 653100China College of Environment and Resources Chongqing Technology and Business UniversityChongqing 400067China College of Chemistry and Chemical Engineering Jiangxi Science and Technology Normal UniversityNanchang 330013China College of Materials and Mechatronics Jiangxi Science and Technology Normal UniversityNanchang 330013China

In order to analyze the influence of the addition of yttrium and manganese on the soot combustion performance and high temperature stability of CeO_(2) catalyst,a series of Y/Mn-modified CeO_(2) catalysts were *** effects of structural properties,textural properties,oxygen vacancies,Ce^(3+),surface adsorbed oxygen species,reduction properties and desorption properties of oxygen species on the activity were analyzed by various characterization *** results of the activity test show that the addition of manganese is beneficial to enhancement of the activity,while the addition of yttrium increases the amount of reactive oxygen species,but decreases the *** aging at 700℃,the activity of the CeMn catalyst decreases most sharply,while the catalytic activity of the CeY catalyst can be maintained to a certain ***,the addition of yttrium and manganese at the same time can stabilize the *** fundamental reason is that yttrium and manganese move to the surface of the solid solution after aging,which increases the reduction performance of the catalyst,thus contributing to the increase of *** the activity of CeYMn catalyst decreases after aging at 800℃,it is still higher than that of other catalysts aged at 700℃.

关键词： CeO_(2)catalyst Soot catalytic combustion Diesel pollution control Rare earths High temperature stability Low temperature reduction performance

Modeling and prediction of tribological properties of copper/aluminum-graphite self-lubricating composites using machine learning algorithms

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Friction 2024年第6期12卷 1322-1340页

作者： huifeng NING Faqiang CHEN Yunfeng SU Hongbin li Hengzhong FAN Junjie SONG Yongsheng ZHANG litian HU School of Electrical and Mechanical Engineering Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

The tribological properties of self-lubricating composites are influenced by many variables and complex ***-driven methods,including machine learning(ML)algorithms,can yield a better comprehensive understanding of complex problems under the influence of multiple parameters,typically for how tribological performances and material properties *** of friction coefficients and wear rates of copper/aluminum-graphite(Cu/Al-graphite)self-lubricating composites with their inherent material properties(composition,lubricant content,particle size,processing process,and interfacial bonding strength)and the variables related to the testing method(normal load,sliding speed,and sliding distance)were analyzed using traditional approaches,followed by modeling and prediction of tribological properties through five different ML algorithms,namely support vector machine(SVM),K-Nearest neighbor(KNN),random forest(RF),eXtreme gradient boosting(XGBoost),and least-squares boosting(LSBoost),based on the tribology experimental *** demonstrated that ML models could satisfactorily predict friction coefficient and wear rate from the material properties and testing method variables ***,the LSBoost model based on the integrated learning algorithm presented the best prediction performance for friction coefficients and wear rates,with R^(2) of 0.9219 and 0.9243,*** importance analysis also revealed that the content of graphite and the hardness of the matrix have the greatest influence on the friction coefficients,and the normal load,the content of graphite,and the hardness of the matrix influence the wear rates the most.

关键词： self-lubricating composites machine learning(ML) tribological properties prediction

术前白介素-6/白介素-10表达对腰椎间盘突出症术后椎间隙感染的预测

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新疆医学 2024年第5期54卷 536-540页

作者：陈超刘永刚李慧峰田冬冬付宇挺左立新安阳市人民医院骨三科河南安阳455000

目的探讨术前白细胞介素-6/白介素-10表达对腰椎间盘突出症术后椎间隙感染的预测价值。方法采用病例对照研究,收集医院2021年1月至2023年1月收治的24例腰椎间盘突出症术后发生椎间隙感染患者的临床资料,纳入发生组,另收集医院同期48例... 详细信息

目的探讨术前白细胞介素-6/白介素-10表达对腰椎间盘突出症术后椎间隙感染的预测价值。方法采用病例对照研究,收集医院2021年1月至2023年1月收治的24例腰椎间盘突出症术后发生椎间隙感染患者的临床资料,纳入发生组,另收集医院同期48例未发生术后椎间隙感染的腰椎间盘症患者临床资料,纳入未发生组。通过查阅腰椎间盘突出症患者病历资料记录基线资料,同时收集所有患者术前白介素-6、白介素-10值,并计算白介素-6/白介素-10值。通过受试者工作曲线(ROC),探讨术前白细胞介素-6/白介素-10表达对腰椎间盘突出症术后椎间隙感染的预测价值。结果发生组住院时间、术前白细胞介素-6、术前白细胞介素-10、术前及术后白细胞介素-6/白细胞介素-10水平大于未发生组,差异有统计学意义(P0,P<0.05)。绘制ROC曲线,结果显示,术前白介素-6/白介素-10预测腰椎间盘突出症术后椎间隙感染发生的曲线下面积(AUC)为0.723,具有一定预测效能。结论术前白细胞介素-6/白介素-10表达对腰椎间盘突出症术后椎间隙感染发生具有较好预测效能,其值越高术后椎间隙感染发生可能性越大。

关键词：腰椎间盘突出症椎间隙感染白介素-6 白介素-10

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基于遗传算法的高速飞行器模糊控制律设计

北京航空航天大学学报 2008年第11期34卷 1250-1253页

作者：李惠峰王健北京航空航天大学宇航学院北京100191

以吸气式高超声速飞行器X-43A的纵向通道为控制对象,针对其6自由度非线性模型设计了飞行控制系统.飞行控制系统包括2个回路,制导回路采用PD控制器,控制回路应用模糊控制器.制导回路负责跟踪轨迹,控制回路执行制导指令.基于遗传算法实现... 详细信息

以吸气式高超声速飞行器X-43A的纵向通道为控制对象,针对其6自由度非线性模型设计了飞行控制系统.飞行控制系统包括2个回路,制导回路采用PD控制器,控制回路应用模糊控制器.制导回路负责跟踪轨迹,控制回路执行制导指令.基于遗传算法实现了PD反馈参数和模糊控制规则的自动优化,无需先验知识和训练数据.在控制飞行器轨迹、姿态和推力时,综合考虑非线性动态特性、不确定性和约束.仿真表明,该方法可以同时满足飞行控制系统鲁棒性和优化过程收敛性的要求.

关键词：高超声速模糊控制 PD控制遗传算法鲁棒性

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基于遗传算法的高速飞行器模糊飞控一体化

北京航空航天大学学报 2009年第1期35卷 44-47页

作者：李惠峰王健北京航空航天大学宇航学院北京100191

以高超声速飞行器通用模型的俯仰通道为控制对象,针对其6自由度非线性模型设计了一体化飞控系统.飞控系统由1个模糊控制器和2个PD控制器组成.基于遗传算法实现了模糊控制规则和PD反馈参数的自动优化,无需先验知识和训练数据.仿真表明,... 详细信息

以高超声速飞行器通用模型的俯仰通道为控制对象,针对其6自由度非线性模型设计了一体化飞控系统.飞控系统由1个模糊控制器和2个PD控制器组成.基于遗传算法实现了模糊控制规则和PD反馈参数的自动优化,无需先验知识和训练数据.仿真表明,该方法可以同时满足飞行控制系统鲁棒性和优化过程收敛性的要求,特别是鲁棒性优于同样采用模糊控制的经典双回路飞控系统.

关键词：高超声速模糊控制 PD控制遗传算法一体化飞控系统鲁棒性

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高超声速巡航飞行器在线自适应反馈控制设计

北京航空航天大学学报 2010年第11期36卷 1382-1386页

作者：李惠峰李昭莹北京航空航天大学宇航学院北京100191

由于飞行器模型的强非线性,各种建模不确定性以及飞行环境的复杂性,高超声速飞行器控制成为一个研究难点.针对某类具有参数不确定性的非线性系统,提出了一种反馈线性化与自适应估计相结合的方法,对非线性系统的输入输出动态应用反馈线... 详细信息

由于飞行器模型的强非线性,各种建模不确定性以及飞行环境的复杂性,高超声速飞行器控制成为一个研究难点.针对某类具有参数不确定性的非线性系统,提出了一种反馈线性化与自适应估计相结合的方法,对非线性系统的输入输出动态应用反馈线性化处理以得到拟线性模型,并设计反馈控制律;对不确定参数采用自适应在线估计,利用Lyapunov方法分析稳定性;针对选择不同输出的情况,对如何消除内动态进行了讨论.为了验证该方法的可行性,将其应用于某高超声速飞行器巡航段纵向非线性模型,对速度和高度通道进行跟踪控制仿真,由于飞行器和大气环境存在建模不确定性,利用自适应控制对不确定参数进行在线估计.仿真结果显示该方法能够快速收敛,并且具有良好的在线自适应能力.

关键词：高超声速飞行器反馈线性化自适应算法稳定性不确定性分析