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Performance of Methanol-to-Olefins Catalytic Reactions by the Addition of PEG in the Synthesis of SAPO-34

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Transactions of Tianjin University 2017年第6期23卷 501-510页

作者： Yaquan Wang Zhao Wang Chao Sun Hengbao Chen hongyao li Haoyang li Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

SAPO-34, a silicoaluminophosphate zeolite, has been synthesized by the hydrothermal method with the addition of different molecular weights of polyethylene glycol (PEG), and has been characterized with XRD, SEM, N2adsorption–desorption, FT-IR, and NH3temperature-programmed desorption (NH3-TPD). We studied SAPO-34 as a catalyst in the methanol-to-olefins (MTO) reaction, in a fixed-bed reactor. The results show that the chain length of PEG has a great influence on the particle size and morphology of SAPO-34. PEG acts as inhibitor in the crystallization process. With the increase of the chain length of PEG used in the synthesis, from a relative molecular weight of 400–6000, the morphology of SAPO-34 changes gradually from cubic to nanoplate-like and then changes to cubic again. The particle size decreases markedly at first and then increases to some extent. The catalytic stability in the MTO reaction also increases first and then decreases, with all the catalysts having almost the same selectivity to olefins. When the sample is synthesized with PEG800, the particles become nanoplate-like with a thickness of 46 nm on average, and the catalytic stability is appreciably prolonged, which is attributed to the shorter diffusion paths of the reactants in the zeolite. © 2017 The Author(s)

关键词： Catalysis Catalyst selectivity Catalysts Chain length Chains Desorption Methanol Molecular weight Nanostructures Olefins Particle size Polyethylene glycols Polyethylenes Zeolites

Facile One-Pot Synthesis of ZSM-5 Aggregates with Interand Intra-Crystalline Mesopores for Methanol to Gasoline Conversion

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Transactions of Tianjin University 2019年第1期25卷 9-22页

作者： Yaquan Wang Chunyang Fan hongyao li Xiao Wang Fanjun Meng Chao Sun liying Sun Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and Technology Tianjin University

ZSM-5 aggregates consisting of superfine and hierarchical nanocrystals(combined with micropores and intra-crystalline mesopores) with an average size of 30 nm were prepared through one-pot synthesis with the assistance of anionic polyacrylamide(APAM). The resultant zeolites(AHN-ZSM-5) were characterized by XRD, ICP-OES, SEM, TEM, BET, NH_3-TPD, Py-IR, and TG analyses and evaluated in the methanol to gasoline(MTG) reaction. Characterization results show that the hierarchical ZSM-5 aggregates possessed two kinds of mesopores, namely inter-and intra-crystalline mesopores. The amount of APAM considerably influenced the mesoporosity and textural properties of AHN-ZSM-5 zeolites. With the addition of APAM in the synthesis, the AHN-ZSM-5 zeolites exhibited large mesopore volume, large external surface area, and appropriate acidity. When applied in the MTG reaction, AHN-ZSM-5 demonstrated a catalytic lifetime that was 1.6 times longer than that of conventional ZSM-5 synthesized in the absence of APAM.

关键词： Hierarchical nanocrystal Intra-crystalline mesopore ZSM-5 aggregate Anionic polyacrylamide Methanol to gasoline

HOW TO EMPHASIZE THE STUDY OF ENGliSH ROOTS AND WORD-BUILDING FOR IMPROVING VOCABULARY TEACHING AT COLLEGE

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Chinese Journal of Applied linguistics 2001年第4期24卷 25-27页

作者： li hongyao Yunnan Traditional Medical College

Guiding college students to acquire an adequate vocabularyis an important task that is often neglected. The morevocabulary hat is mastered, the higher level a learner of Englishwill have. But in China, the traditional method of teachingvocabulary is learning by rote, and learners of foreign languagesare inclined to learn as much vocabulary as possible this wayregardless of whether these vocabulary is useful or not. Indeed,there are some disadvantageous factors hindering the studentsfrom expanding vocabulary rapidly and efficiently. We have todevelop a scientific method of teaching vocabulary exploringmethods of which is the key to this article.

关键词： HOW TO EMPHASIZE THE STUDY OF ENGliSH ROOTS AND WORD-BUILDING FOR IMPROVING VOCABULARY TEACHING AT COLLEGE

Ferroptosis and its emerging roles in acute pancreatitis

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Chinese Medical Journal 2022年第17期135卷 2026-2034页

作者： hongyao li Yujie lin ling Zhang Jing Zhao Peiwu li Department of Emergency Lanzhou University Second HospitalLanzhou UniversityLanzhouGansu 730030China

Acute pancreatitis(AP)is a common and potentially life-threatening pancreatic inflammatory *** it is usually self-limiting,up to 20%of patients will develop into severe *** may lead to systemic inflammatory response syndrome and multiple organ dysfunction,affecting the lungs,kidneys,liver,heart,*** patients usually have sequelae of varying degrees,such as chronic hyperglycemia after AP(CHAP),pancreatic exocrine insufficiency,and chronic *** specific target treatments is the main reason for high mortality and morbidity,which means that more research on the pathogenesis of AP is *** is a newly discovered regulated cell death(RCD),originally described in cancer cells,involving the accumulation of iron and the depletion of plasma membrane polyunsaturated fatty acids,and a caspase-independent *** is closely related to neurological diseases,myocardial infarction,ischemia/reperfusion injury,cancer,*** in the past years has also found the effects of ferroptosis in AP,pancreatic cancer,and AP complications,such as acute lung injury and acute kidney *** article reviews the research progress of ferroptosis and its association with the pathophysiological mechanisms of AP,trying to provide new insight into the pathogenesis and treatment of AP,facilitating the development of better-targeted drugs.

关键词： Acute pancreatitis Ferroptosis RCD Autophagy GPX4 PUFAs Regulated cell death

Activation of astroglial group Ⅱ and Ⅲ metabotropic glutamate receptors protects midbrain neurons against LPS or MPP^＋ -induced neurotoxicity

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中国药理通讯 2004年第2期21卷 22-23页

作者： Hong-hongyao FangWang FangZhou li-FangHu TaoSun Jian-HuaDing GangHu DepartmentofPharmacology＆Neurobiology NanjingMedicalUniversityNanjing210029

AIM: Activation of glial metabotropic glutamate receptors (mGluRs) may be proved to play a critical role for neuroprotection in neurodegenerative diseases. Excess glutamate induced-excitoxicity is implicated in the initiation or progression of the neurodegenerative process. Glutamate accumulation in the central nervous system mediated by inhibiting

关键词：聚合物代谢作用谷氨酸酯细胞受体中脑神经元 LPS

Adaptive fuzzy PI tracking control for a class of switched nonlinear systems

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Adaptive fuzzy PI tracking control for a class of switched n...

基于决策融合的多无人机协同目标检测识别算法

第三十九届中国控制会议

作者： hongyao li Haibin Sun linlin Hou Qixun Lan School of Engineering Qufu Normal University School of Information Science and Engineering Qufu Normal University School of Mathematics and science Henan University of Urban Construction

In this paper, the adaptive fuzzy proportional-integral（PI） tracking control problem for a class of switched nonlinear systems with unknown nonlinear functions and external disturbances is studied. By using backstepping method with fuzzy logic systems, an adaptive fuzzy PI tracking controller is proposed, which has a simple structure and a clear physical meaning. The stability analysis of the closed-loop switched systems is established via common Lyapunov function, and all the closed-loop signals and tracking error are bounded. Finally, two example are employed to verify the effectiveness of the proposed scheme.

关键词： Adaptive control backstepping fuzzy logic systems PI control switched nonlinear system tracking control

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系统工程与电子技术 2022年第3期44卷 746-754页

作者：李洪瑶李小强韩心中谢学立席建祥火箭军工程大学导弹工程学院西安陕西710025 火箭军研究院北京100094

针对现阶段单无人机不能高效完成大区域巡视的问题,提出一种多无人机决策融合的目标检测识别算法。首先改进Retinanet算法进行单无人机的目标检测,根据航拍图像目标特性,调整anchor参数和训练策略。同时利用特征提取算子配准多无人机航... 详细信息

针对现阶段单无人机不能高效完成大区域巡视的问题,提出一种多无人机决策融合的目标检测识别算法。首先改进Retinanet算法进行单无人机的目标检测,根据航拍图像目标特性,调整anchor参数和训练策略。同时利用特征提取算子配准多无人机航拍图像,实现多机图像坐标一致,并进行图像拼接。然后综合目标的位置信息和属性信息对多机图像进行目标关联。最后提出一种基于冲突度量的动态切换策略,自适应选择DST(dempster-shafer theory)或DSmT(desert-smarandache theory)融合关联目标信息。在多无人机协同目标识别数据集上进行实验,结果表明所提算法能在增大单次巡视范围的同时,提高无人机巡视系统的检测精度。

关键词：机器视觉多无人机协同目标检测多目标关联动态切换策略

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高校青年拔尖创新人才的核心特质、成长规律与培养策略

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华南师范大学学报（社会科学版） 2024年第5期 44-56,207页

作者：张沛然李红瑶李广东北师范大学教师教育研究院长春130024 东北师范大学教育学部长春130024

创新是推动经济社会发展的战略支点,拔尖创新人才则是提升国家整体创新水平、推动新质生产力发展的关键因素。高校青年拔尖创新人才作为国家、高校发展的中坚力量,其专业发展是服务国家战略需求的关键路径。高校青年拔尖创新人才具有崇... 详细信息

创新是推动经济社会发展的战略支点,拔尖创新人才则是提升国家整体创新水平、推动新质生产力发展的关键因素。高校青年拔尖创新人才作为国家、高校发展的中坚力量,其专业发展是服务国家战略需求的关键路径。高校青年拔尖创新人才具有崇高的历史使命、融合的多重思维、执着的探索精神三大核心特质,受到环境孵化下的共生效应规律、能力涌现下的积累效应规律以及团队共建下的群体效应规律共同作用。针对高校青年拔尖创新人才的培养,应以引才聚才为目的创设梯次合理、衔接紧密的成长通道,以量才促才为核心制定契合度高、针对性强的评价政策,以容才敬才为追求构建可持续性、高质量发展的激励机制。这一系列举措旨在探索并推进一条兼具中国特色与世界一流水平的高校青年拔尖创新人才自主培育之路。

关键词：青年拔尖创新人才核心特质成长规律培养策略

γ-分泌酶抑制剂(LY411575)的合成工艺研究

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高等学校化学学报 2017年第2期38卷 200-205页

作者：郭宏垚李冬雷雄张旭许人军王锋李稳宏西北大学化工学院西安710069 西安市轻工业研究所西安710001

对γ-分泌酶抑制剂(LY411575)的合成路线进行改进,新合成路线下该化合物的总收率为35%,比文献方法提高了16%;对关键中间体提前进行了手性拆分,从而使在制备最终产品的后3步反应中用到的原料减少了50%,降低了反应成本和最终产品的纯化难... 详细信息

对γ-分泌酶抑制剂(LY411575)的合成路线进行改进,新合成路线下该化合物的总收率为35%,比文献方法提高了16%;对关键中间体提前进行了手性拆分,从而使在制备最终产品的后3步反应中用到的原料减少了50%,降低了反应成本和最终产品的纯化难度.另外,对拆分过程中的主要因子进行了单因素实验,考察了各因素对产品的e.e.值和反应收率的影响.获得了最佳反应条件:D-(+)-二对甲基苯甲酰酒石酸为拆分试剂,甲醇作溶剂,加热到回流溶解,加入的溶剂量为每g底物12 m L,从回流降到室温所用时间控制在120 min,拆分的收率为40%,e.e.值为99%.

关键词：阿尔茨海默病 γ-分泌酶关键中间体抑制剂