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Research on Ethylene and Propylene Formation during Catalytic Pyrolysis of Methylcyclohexane

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China Petroleum Processing & Petrochemical Technology 2012年第4期14卷 73-79页

作者： yu Shan Zhang Jiushun Wei Xiaoli Research Institute of Petroleum Processing SINOPEC

The influence of operating parameters and type of zeolite catalysts on formation of ethylene and propylene during catalytic pyrolysis of methylcyclohexane (MCH) was studied in a laboratory fixed fluidized bed reactor. The results indicated that higher reaction temperature and lower WHSV tended to produce more ethylene and propylene, among which the reaction temperature was an important factor influencing the ethylene formation. Compared with the FAU and BEA type zeolites, the MFI structured zeolite catalyst, thanks to more acid sites and smaller pore diameter of the catalyst, was conducive to the formation of ethylene and propylene. The protonation occurred on different C—C bonds and C—H bonds in the carbon chain of MCH led to different product slates, and the protonation on C—C bonds located at naphthenic ring was favorable to the formation of ethylene and propylene.

关键词： methylcyclohexane catalytic pyrolysis ethylene propylene reaction pathway

Analytical modeling and simulation on lateral mechanical characteristics of high-speed train traction motor hanging leaf spring

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International Journal of Modeling, Simulation, and Scientific Computing 2019年第3期10卷 146-163页

作者： yuewei yu Leilei Zhao Changcheng Zhou School of Transportation and Vehicle Engineering Shandong University of Technology ZiboP.R.China School of Automation Beijing University of Posts and TelecommunicationsBeijingP.R.China

In this paper,using the theoretical analysis method,according to the actual structure of the hanging leaf spring of the traction motor mounted on the frame,the lateral force model of the hanging leaf spring of the traction motor was ***,through theoretical deduction,the deformation analytical calculation formula and the stress analytical calculation formula of the hanging leaf spring were *** correctness of the leaf spring’s lateral force model was established and its deformation and stress analytical formulae were verified using ANSYS finite element analysis *** on this,according to the deformation analytical formula and the stress analytical formula of the leaf spring established,the influence of the main structural parameters on the mechanical characteristics of the leaf spring was discussed,and the reliability of the analytical analysis method of the lateral mechanical characteristics of the traction motor hanging leaf spring was verified by the loading–unloading *** results show that the deformation and the load of the leaf spring change *** changes of leaf spring’s stress at different positions can be considered as being composed of three sections:a linear change section in the root,a nonlinear change section in the middle,and a nonlinear change section in the *** the structural parameters,the end thickness h2 has the greatest influence on the stiffness and the stress of the leaf spring,and the maximum thickness of the leaf spring eye h1 has the least influence on the stiffness and the stress of the leaf *** influence degree of other parameters on the stiffness of the leaf spring is h_(3),L_(1),L_(3),L_(2) in order,and the influence degree on the stress of the leaf spring is h_(3),L_(1),L_(2),L_(3) in *** addition,when the root thickness h_(3) is greater than a certain value,the maximum stress point of the leaf spring appears at the end position L_(2).This study can provide a useful reference for

关键词： High-speed train traction motor hanging leaf spring analytical calculation lateral mechanical characteristics analysis

党参总皂苷对衰老小鼠认知功能障碍保护作用及机制

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中国实验方剂学杂志 2024年第20期30卷 70-76页

作者：张重阳于淼陈荣昌张彬孙晓波舒尊鹏广东药科大学中药学院广州510006 中国医学科学院药用植物研究所药理毒理中心北京100193 北京师范大学文理学院广东珠海519087

目的:探究党参总皂苷(TSC)对d-半乳糖诱导的衰老小鼠学习记忆功能损伤的改善作用及机制。方法:将24只雄性C57BL/6J小鼠随机分出正常组、模型组、党参总皂苷组(200 mg·kg^(-1))、多奈哌齐组(3 mg·kg^(-1)),每组6只。预给药1周,采用预... 详细信息

目的:探究党参总皂苷(TSC)对d-半乳糖诱导的衰老小鼠学习记忆功能损伤的改善作用及机制。方法:将24只雄性C57BL/6J小鼠随机分出正常组、模型组、党参总皂苷组(200 mg·kg^(-1))、多奈哌齐组(3 mg·kg^(-1)),每组6只。预给药1周,采用预防性给药对d-半乳糖诱导小鼠衰老模型进行干预8周,第9周采用Morris水迷宫实验检测衰老小鼠的学习和记忆能力;采用苏木素-伊红(HE)、尼氏染色法检测脑组织病理损伤;采用免疫组化检测脑组织中核转录因子-κB(NF-κB)蛋白、肿瘤坏死因子-α(TNF-α)、脑源性神经营养因子(BdNF)的表达;采用酶联免疫吸附测定法(ELISA)测定血清谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)、超氧化物歧化酶(SOd)、丙二醛(MdA)、TNF-α、白细胞介素-1β(IL-1β)和白细胞介素-18(IL-18)水平,分析TSC对d-半乳糖诱导的小鼠脑部神经炎症及记忆功能损伤的改善作用。结果:与正常组比较,模型组小鼠认知功能明显下降;模型组小鼠血清抗氧化酶CAT、SOd、GSH-Px活力显著降低(PdA、TNF-α、IL-1β和IL-18水平显著升高(PdNF的表达水平明显下调(Pd-半乳糖诱导的小鼠认知功能障碍;显著提高血清中抗氧化酶CAT、SOd、GSH-Px活力(PdA、TNF-α、IL-1β和IL-18水平(PdNF的表达明显上调(Pd-半乳糖诱导的衰老小鼠的认知功能障碍具有保护作用,其保护作用可能与抑制氧化应激和炎症反应有关。

关键词：党参总皂苷炎症衰老认知功能氧化应激

灵芝-玉米秸秆的生物纸板制备工艺优化及性能研究

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农业工程学报 2024年第18期40卷 302-310页

作者：董紫薇李宇航李凡宇王正奇李玉韩雪容吉林农业大学食药用菌教育部工程研究中心长春130118 吉林农业大学吉林省菌物表型组学重点实验室长春130118

为解决使用化学粘合剂制备的纸板带来的环境污染以及健康损害等问题,可替代传统纸板的环境友好型生物纸板开发成为研究热点。该研究使用韦伯灵芝/玉米秸秆组合,通过优化培养时间、果糖添加量及秸秆颗粒度等单因素条件探究其对制备的菌... 详细信息

为解决使用化学粘合剂制备的纸板带来的环境污染以及健康损害等问题,可替代传统纸板的环境友好型生物纸板开发成为研究热点。该研究使用韦伯灵芝/玉米秸秆组合,通过优化培养时间、果糖添加量及秸秆颗粒度等单因素条件探究其对制备的菌丝体纸板力学、防水和热分解性能的影响,并通过正交试验明确纸板的最佳培养工艺。试验结果表明,各因素对纸板的边压强度、弯曲挺度、静曲强度的影响程度由大到小依次为颗粒度,培养时间,果糖添加量,当颗粒度为0.165~0.250 mm,培养时间30 d,添加质量分数为5%的果糖时,制备的纸板边压强度为14.36 N/mm、静曲强度为10.89 MPa、弯曲挺度为33.09 mN/m,并且随着颗粒度的减小,纸板吸水24 h的吸水率和厚度膨胀率分别降低到0.86%和0.50%。不同单因素条件制备的菌丝体纸板具有相似的热降解过程,均在170℃左右开始降解,在350℃达到最大。该研究为后续菌丝体复合材料的开发和应用提供参考依据。

关键词：菌丝体复合材料力学性能防水性能生物质

古代经典名方中药复方制剂的转化研究与审评决策思路

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中药药理与临床 2024年第3期40卷 2-7页

作者：宋菊阳长明于江泳韩炜曲建博赵军宁国家药品监督管理局药品审评中心北京100076 国家药品监督管理局北京100037

古代经典名方是历代医家临床经验的总结,做好古代经典名方中药复方制剂的研究转化,对于中药传承创新发展意义重大。近年中医药在新型冠状病毒肺炎大流行防治过程中的及时性、可及性、可负担性,也凸显了加快古代经典名方新药转化的重要... 详细信息

古代经典名方是历代医家临床经验的总结,做好古代经典名方中药复方制剂的研究转化,对于中药传承创新发展意义重大。近年中医药在新型冠状病毒肺炎大流行防治过程中的及时性、可及性、可负担性,也凸显了加快古代经典名方新药转化的重要性。古代经典名方中药复方制剂的研发依据是因为其“至今仍广泛应用、疗效确切、具有明显特色与优势”,其安全性和有效性得到长期使用验证,因此与以往的中药复方制剂新药的研发模式、逻辑和技术要求存在差异。本文通过对中药复方制剂研发模式的思考,对古代经典名方中药复方制剂的提出与实践、研发审评逻辑与技术要求等进行了分析,并结合研发和审评实际进行了思考和讨论,以期为古代经典名方复方制剂研发提供参考。

关键词：古代经典名方古代经典名方中药复方制剂研发模式技术要求中药监管科学

demonstration of the approximation of eliminating atomic excited populations in an atom-cavity system

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Chinese Physics B 2012年第2期21卷 272-277页

作者： Zhang yu-Qing Huang Gang Tan Lei Institute of Theoretical Physics Lanzhou UniversityLanzhou 730070China Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou UniversityLanzhou 730000China

Using the master equation approach to a V-type three-level atom inside a high-finesse single-mode cavity in the strong coupling condition, we demonstrate the approximation of eliminating populations of atomic excited states, which is widely used in the field of the atom cavity systems [Hechenblaikner G, Gangl M, Horak P and Ritsch H 1998 Phys. Rev. A 58 3030]; Liu L W, Tan T and Xu Y 2008 J. Mod. Opt. 56 968; Cho J, Angelakis d G and Bose S 2008 Phys. Rev. A 78 062338. This is reflected in the deviation of the population 5, of which the value is 10^-3 - 10^-2. We further find the deviation of the dipole force and demonstrate that the deviation of atomic population will not notably affect the dipole force of the atom in the strong coupling condition. A relevant experimental case is also presented.

关键词： V-type three-level atom high finesse optical cavity dipole force strong coupling condition

Evaluation of gases'molecular abundance ratio by fiber-optic laser-induced breakdown spectroscopy with a metal-assisted method

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Plasma Science and Technology 2021年第12期23卷 176-182页

作者： yu ZHU Pingwei ZHOU Shengfu LI Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 621900People's Republic of China

A metal-assisted method is proposed for the evaluation of gases’molecular abundance ratio in fiber-optic laser-induced breakdown spectroscopy(FO-LIBS).This method can reduce the laser ablation energy and make gas composition identification *** principle comes from the collision between the detected gases and the plasma produced by the laser ablation of the metal *** interparticle collision in the plasma plume leads to gas molecules dissociating and sparking,which can be used to determine the gas *** quantitative relationship between spectral line intensity and molecular abundance ratio was developed over a large molecular abundance ratio *** influence of laser ablation energy and substrate material on gas quantitative calibration measurement is also *** proposed metal-assisted method makes the measurement of gases’molecular abundance ratios possible with an FO-LIBS system.

关键词： gases’molecular abundance ratio collision of plasma fiber optical laser induced breakdown spectroscopy metal assisted method

不同粒径曲霉-好氧颗粒污泥的微环境对脱氮除磷能力影响

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环境工程学报 2024年第1期18卷 169-180页

作者：靳宇张秋华胡腾辉熊玮苏海佳王少杰北京化工大学生命科学与技术学院北京100029

针对目前实验室好氧颗粒污泥颗粒化慢,稳定性差等问题。以自发成球的曲霉为核心,开发了絮状污泥的快速颗粒化技术,提高体系运行稳定性。对形成的大(3.0 mm<d≤5.0 mm)、中(1.5 mm<d≤3.0 mm)、小(d≤1.5 mm)3种尺寸的曲霉-好氧颗粒污泥(... 详细信息

针对目前实验室好氧颗粒污泥颗粒化慢,稳定性差等问题。以自发成球的曲霉为核心,开发了絮状污泥的快速颗粒化技术,提高体系运行稳定性。对形成的大(3.0 mmd≤5.0 mm)、中(1.5 mmd≤3.0 mm)、小(d≤1.5 mm)3种尺寸的曲霉-好氧颗粒污泥(Aspergillus-AGS)进行了性能对比,然后结合脱氮除磷性能实验监测数据,对曲霉投加后菌群结构的演变进行分析。大尺寸的Aspergillus-AGS是最优选,能促进胞外多聚物的分泌,从而有利于颗粒化性能提高,维持颗粒稳定结构,并且提高了污染物去除效率。在投加不同粒径的反应器中,通过菌群分析,曲霉Aspergillus作为优势载体菌种在对照组絮状污泥、大、中和小尺寸反应器中占比分别是4.17%、85.67%、47.20%和58.00%。此外,大尺寸颗粒反应器中,细菌种类NOB、PAO占比相比其他反应器明显更高,其中反硝化菌Ferruginibacter、Castellaniella等丰度较高,脱氮除磷有明显优势,L-AGS体系6 h内氨氮的去除率为77.2%,总氮去除率为52.8%,总磷的去除率为49.2%,硝酸盐的去除率为93.9%。

关键词：好氧颗粒污泥霉菌粒径微环境脱氮除磷

Commutators of Calderón-Zygmund operators related to admissible functions on spaces of homogeneous type and applications to Schrdinger operators

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Science China Mathematics 2013年第9期56卷 1895-1913页

作者： LIU yu HUANG JiZheng dONG JianFeng School of Mathematics and Physics University of Science and Technology Beijing College of Sciences North China University of Technology department of Mathematics Shanghai University

Let X be an Rd-space. In this paper, the authors establish the boundedness of the commutator Tbf = bTf-T(bf) on Lp , p∈(1,∞), where T is a Calderón-Zygmund operator related to the admissible function ρ and b∈BMOθ(X)BMO(X). Moreover, they prove that Tb is bounded from the Hardy space H1ρ(X) into the weak Lebesgue space L1weak(X). This can be used to deal with the Schrdinger operators and Schrdinger type operators on the Euclidean space Rn and the sub-Laplace Schrdinger operators on the stratified Lie group G.

关键词： commutator spaces of homogeneous type stratified Lie groups admissible function Hardy space reverse Ho¨lder inequality Riesz transform Schr¨odinger operators