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Vibration Suppression for Active Magnetic Bearings Using Adaptive Filter with Iterative Search Algorithm

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 61-71页

作者： Jin-hui ye Dan Shi Yue-Sheng Qi Jin-hui Gao Jian-Xin Shen IEEE Department of Electrical Engineering Zhejiang UniversityHangzhou 310027China CES and IEEE

Active Magnetic Bearing(AMB) is a kind of electromagnetic support that makes the rotor movement frictionless and can suppress rotor vibration by controlling the magnetic force. The most common approach to restrain the rotor vibration in AMBs is to adopt a notch filter or adaptive filter in the AMB controller. However, these methods cannot obtain the precise amplitude and phase of the compensation current. Thus, they are not so effective in terms of suppressing the vibrations of the fundamental and other harmonic orders over the whole speed range. To improve the vibration suppression performance of AMBs,an adaptive filter based on Least Mean Square(LMS) is applied to extract the vibration signals from the rotor displacement signal. An Iterative Search Algorithm(ISA) is proposed in this paper to obtain the corresponding relationship between the compensation current and vibration signals. The ISA is responsible for searching the compensating amplitude and shifting phase online for the LMS filter, enabling the AMB controller to generate the corresponding compensation force for vibration suppression. The results of ISA are recorded to suppress vibration using the Look-Up Table(LUT) in variable speed range. Comprehensive simulations and experimental validations are carried out in fixed and variable speed range, and the results demonstrate that by employing the ISA, vibrations of the fundamental and other harmonic orders are suppressed effectively.

关键词： Active Magnetic Bearing(AMB) Adaptive filter Iterative search algorithm Least mean square(LMS) Vibration suppression

Atroposelective Synthesis of 2-Arylindoles via Chiral Phosphoric Acid-Catalyzed Direct Amination of Indoles

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Chinese Journal of Chemistry 2024年第7期42卷 731-735页

作者： Wen Bao ye-hui Chen Yu-Wei Liu Shao-Hua Xiang Bin Tan School of Pharmacy&StateKey Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhouGansu 730000China Shenzhen Grubbs Institute Department of ChemistrySouthern University of Science and TechnologyShenzhenGuangdong 518055China

Indole-based atropisomers are a very important class of axially chiral ***,the atroposelective synthesis of axially chiral 2-arylindole remains largely *** this study,we report the successful synthesis of atropisomeric 2-arylindoles using direct amination of indoles with p-quinonediimines in the presence of chiral phosphoric acid as a *** acts as an aminating reagent through formal polarity inversion of *** malonate group on the 2-aryl of 2-indoles was found to be essen-tial for high enantioselectivity of the *** could be due to the additional interaction between the ester group and the cata-lyst,as well as the intramolecular hydrogen *** findings provide a new strategy for the asymmetric construction of 2-arylindole atropisomers.

关键词： Chiral phosphoric acid Quinonediimines Direct amination Nucleophilic addition Asymmetric catalysis Enantioselectivity Axially chiral 2-arylindole Atroposelective synthesis

Effect and mechanism of Qingre Huashi decoction on drug-resistant Helicobacter pylori

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World Journal of Gastroenterology 2024年第24期30卷 3086-3105页

作者： Miao-Miao Lin Shan-Shan Yang Qiu-Yue Huang Guang-hui Cui Xiao-Fen Jia Yao Yang Zong-Ming Shi hui ye Xue-Zhi Zhang Department of Integrated Traditional Chinese and Western Medicine Peking University First HospitalBeijing 100034China Institute of Integrated Traditional Chinese and Western Medicine Peking UniversityBeijing 100034China

BACKGROUND Helicobacter pylori(HP),the most common pathogenic microorganism in stomach,can induce inflammatory reactions in the gastric mucosa,causing chronic gastritis and even gastric *** infection affects over 4.4 billion people globally,with a worldwide infection rate of up to 50%.The multidrug resistance of HP poses a serious challenge to *** has been monstrated that compared to bismuth quadruple therapy,Qingre Huashi decoction(QHD)combined with triple therapy exhibits comparable eradication rates but with a lower incidence of adverse reactions;in addition,QHD directly inhibit and kill HP in *** In this study,12 HP strains were isolated in vitro after biopsy during gastroscopy of HP-infected *** vitro,the minimum inhibitory concentration(MIC)values for clinical HP strains and biofilm quantification were determined through the E-test method and crystal violet staining,*** most robust biofilm-forming strain of HP was selected,and QHD was evaluated for its inhibitory and bactericidal effects on the strain with strong biofilm *** assessment was performed using agar dilution,E-test,killing dynamics,and transmission electron microscopy(TEM).The study also explored the impact of QHD on antibiotic resistance in these HP strains with strong biofilm *** violet method,scanning electron microscopy,laser confocal scanning microscopy,and(p)ppGpp chromatographic identification were employed to evaluate the effect of QHD on biofilm in strong biofilm-forming HP *** effect of QHD on biofilm and efflux pump-related gene expression was evaluated by quantitative polymerase chain ***-targeted metabolomics with UHPLC-MS/MS was used to identify potential metabolic pathways and biomarkers which were different between the NC and QHD *** HP could form biofilms of different degrees in vitro,and the intensity of formation was associated with the drug resistance of the *** had str

关键词： Qingre Huashi decoction Helicobacter pylori Drug resistance Biofilm Metabolomics

Atomically Precise Design of PtSn Catalyst for the Understanding of the Role of Sn in Propane Dehydrogenation

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Precision Chemistry 2024年第6期2卷 245-255页

作者： hui ye Lina Cao Minghui Gu Han Nie Qingqing Gu Bing Yang Yunxing Bai Qinxue Nie Weixin Huang Junling Lu Institute of Advanced Technology Key Laboratory of Precision and Intelligent ChemistryDepartment of Chemical PhysicsHefei National Research Center for Physical Sciences at the MicroscaleKey Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education InstitutesUniversity of Science and Technology of ChinaHefei 230026P.R.China CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsThe Chinese Academy of SciencesDalian 116023P.R.China

Propane dehydrogenation(PDH),an atom-economic reaction to produce high-value-added propylene and hydrogen with high efficiency,has recently attracted extensive *** severe deactivation of Pt-based catalysts through sintering and coking remains a major challenge in this high-temperature *** introduction of Sn as a promoter has been widely applied to improve the stability and selectivity of the ***,the selectivity and stability of PtSn catalysts have been found to vary considerably with synthesis methods,and the role of Sn is still far from fully *** gain in-depth insights into this issue,we synthesized a series of PtSn/SiO_(2)and SnPt/SiO_(2)catalysts by varying the deposition sequence and Pt:Sn ratios using atomic layer deposition with precise *** found that PtSn/SiO_(2)catalysts fabricated by the deposition of SnO_(x)first and then Pt,exhibited much better propylene selectivity and stability than the SnPt/SiO_(2)catalysts synthesized the other way *** demonstrate that the presence of Sn species at the Pt-SiO_(2)interface is of essential importance for not only the stabilization of PtSn clusters against sintering under reaction conditions but also the promotion of charge transfers to Pt for high *** the above,the precise regulation of the Sn content is also pivotal for high performance,and the excess amount of Sn might generate additional acidic sites,which could decrease the propylene selectivity and lead to heavy coke *** findings provide deep insight into the design of highly selective and stable PDH catalysts.

关键词： Propane dehydrogenation PtSn catalysts sintering coke formation acidity

考虑追责机制的复杂武器装备交付链式多任务激励模型

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控制与决策 2024年第1期39卷 301-310页

作者：张叶卉朱建军南京航空航天大学经济与管理学院南京2111061

复杂武器装备的交付效率直接影响国防战斗力的转化,为提高交付效率,基于复杂武器装备交付问题处理的多任务特点,建立考虑追责机制的交付链式激励契约模型,探究在信息对称和信息不对称两种情况下追责机制、公平偏好、风险类型、依赖等因... 详细信息

复杂武器装备的交付效率直接影响国防战斗力的转化,为提高交付效率,基于复杂武器装备交付问题处理的多任务特点,建立考虑追责机制的交付链式激励契约模型,探究在信息对称和信息不对称两种情况下追责机制、公平偏好、风险类型、依赖等因素对激励契约的影响.研究表明:公平偏好因素对各技术业务部门的努力水平有明显激励作用;代理人在相对重要且成本系数低的交付任务上投入了更多的努力;部门的综合技术水平、依赖系数、公平偏好对最优激励契约的影响与其风险偏好类型以及风险偏好程度相关;追责机制在一定程度上能够提高整体努力水平和收益分成比例,但是过高的追责能力水平反而会降低交付积极性.研究结论可为复杂装备交付环节激励契约设计提供理论支撑和依据.

关键词：复杂武器装备多任务交付委托代理激励契约追责机制

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谷氨酰胺代谢抑制剂调节肿瘤免疫的研究进展

中国新药与临床杂志 2024年第8期43卷 568-573页

作者：朱仲玲史业辉天津医科大学肿瘤医院药理研究室/国家恶性肿瘤临床医学研究中心/天津市恶性肿瘤临床医学研究中心/天津市肿瘤防治重点实验室天津300060

谷氨酰胺(Gln)是机体关键的碳元素和氮元素供体以及能量来源,不仅对肿瘤的发生发展至关重要,还参与调节免疫细胞的发育和活化。快速增殖的肿瘤细胞会从肿瘤微环境中大量摄取营养物质,由此导致的Gln匮乏会显著抑制T细胞的活性和功能,诱导... 详细信息

谷氨酰胺(Gln)是机体关键的碳元素和氮元素供体以及能量来源,不仅对肿瘤的发生发展至关重要,还参与调节免疫细胞的发育和活化。快速增殖的肿瘤细胞会从肿瘤微环境中大量摄取营养物质,由此导致的Gln匮乏会显著抑制T细胞的活性和功能,诱导T细胞耗竭。Gln抗代谢物、谷氨酰胺酶抑制剂、Gln摄取抑制剂等Gln代谢抑制剂能够显著抑制肿瘤细胞的生长增殖,同时不会加剧T细胞耗竭,反而可通过调控免疫检查点表达、细胞外基质结构重塑、肿瘤相关巨噬细胞极化等多重机制改善肿瘤微环境,增强抗肿瘤免疫反应。Gln代谢抑制剂与免疫检查点抑制剂联合使用还可发挥协同增效的作用。

关键词：谷氨酰胺肿瘤微环境免疫靶向药物

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熔石英元件磁性复合流体抛光去除特性研究

红外与激光工程 2024年第7期53卷 214-225页

作者：叶卉李壮王健姜晨孙来喜上海理工大学机械工程学院上海200093 中国工程物理研究院激光聚变研究中心四川绵阳621900

基于磁性复合流体(Magnetic Compound Fluid,MCF)抛光技术开展了熔石英元件抛光工艺研究,对比了传统MCF和超声辅助MCF(以下简称UMCF)抛光对熔石英材料去除特性的影响,探究了不同抛光时间下MCF和UMCF抛光对熔石英材料去除量/去除率和表... 详细信息

基于磁性复合流体(Magnetic Compound Fluid,MCF)抛光技术开展了熔石英元件抛光工艺研究,对比了传统MCF和超声辅助MCF(以下简称UMCF)抛光对熔石英材料去除特性的影响,探究了不同抛光时间下MCF和UMCF抛光对熔石英材料去除量/去除率和表面粗糙度的影响,并构建了与抛光应力和抛光时间有关的材料去除率模型。研究结果表明,相较于传统MCF,UMCF在提高材料去除率和降低表面粗糙度方面均有优势。两种抛光方式下材料去除机制均为弹塑性去除,UMCF抛光获得的表面粗糙度相比于MCF抛光优化了68.88%。由于流体动压力和超声振动压力的联合作用,UMCF抛光材料去除率最高可达5.74×10^(-3)mm^(3)/min,相比于MCF抛光提升了4.04倍。MCF和UMCF抛光材料去除率与抛光应力和抛光时间均呈现幂函数相关性,且在UMCF抛光中抛光应力对去除率的影响权重大于MCF抛光。

关键词：磁性复合流体抛光超声振动辅助材料去除率粗糙度抛光应力

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太阳能电池用球形银颗粒的液相法制备研究

材料导报 2024年第1期38卷 126-130页

作者：叶慧沈天成陈远志徐进厦门大学材料学院福建厦门361000

本工作以硝酸银为银前驱体,抗坏血酸为还原剂,结合表面活性剂的作用,制备了平均粒径为(1.88±0.25)μm的球形银颗粒,同时,研究了还原体系中表面活性剂对银颗粒形貌及尺寸分布的影响,结果表明,柠檬酸三钠能够促进片状纳米银的形成。片状... 详细信息

本工作以硝酸银为银前驱体,抗坏血酸为还原剂,结合表面活性剂的作用,制备了平均粒径为(1.88±0.25)μm的球形银颗粒,同时,研究了还原体系中表面活性剂对银颗粒形貌及尺寸分布的影响,结果表明,柠檬酸三钠能够促进片状纳米银的形成。片状纳米银在长链表面活性剂(阿拉伯树胶、聚乙烯吡咯烷酮、聚乙二醇4000的质量比为4∶1∶1)存在时能够发生有序的自组装,得到表面相对光滑、粒径分布均匀的高球形度银颗粒。抗坏血酸的还原能力随着pH值的增加而逐渐增强。此外,本工作将所得银颗粒与有机载体及玻璃粉混合,通过丝网印刷于硅基底上,850℃烧结后,得到电阻率为3.11μΩ·cm的导电厚膜。

关键词：银颗粒协同作用晶体生长导电膜

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地铁地下车站水消防系统设计的优化研究

福建建筑 2024年第4期 123-126页

作者：叶晖福州轨道交通设计院有限公司福建福州350001

在消防安全、节能减排、节约工程投资的基础上,对地铁地下车站常规室内外消火栓系统设置方案及自动喷水灭火系统的设置范围提出优化建议。分析并探讨利用市政管网进行稳压、地铁地下车站设置区域消防系统,以及区间采用常高压系统的可行... 详细信息

在消防安全、节能减排、节约工程投资的基础上,对地铁地下车站常规室内外消火栓系统设置方案及自动喷水灭火系统的设置范围提出优化建议。分析并探讨利用市政管网进行稳压、地铁地下车站设置区域消防系统,以及区间采用常高压系统的可行性。同时,对地下车站室外水消防方案争议点进行归纳,提出地下车站室外水消防设置建议;对地铁地下车站设置自动喷水灭火系统优缺点进行分析,提出地下车站设置自动喷水灭火系统的设置条件和范围。

关键词：地铁水消防消火栓系统自动喷水灭火系统