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基于滤波器组分解的周期性振动冲击信号解调方法及其应用

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振动与冲击 2008年第8期27卷 133-137页

作者：胡晓依何庆复王华胜丁福焰北京交通大学机械与电子控制工程学院北京100044 铁道科学研究院机车车辆研究所北京100081

针对离散小波包变换用于振动信号解调分析存在的不足,构造了一种具有线性相位的两通道正交镜像对称滤波器组(QMF)用于信号解调分析;与同阶的小波滤波器相比,此QMF滤波器不仅滤波性能更优,而且其滤波系数的求取更加便捷。为了解决常规两... 详细信息

针对离散小波包变换用于振动信号解调分析存在的不足,构造了一种具有线性相位的两通道正交镜像对称滤波器组(QMF)用于信号解调分析;与同阶的小波滤波器相比,此QMF滤波器不仅滤波性能更优,而且其滤波系数的求取更加便捷。为了解决常规两通道滤波器组分解算法中存在的子带信号组频带错位问题,引入了无频带错位的QMF滤波器组分解算法。基于此分解算法,提出了一种用于早期故障自动检测的振动信号解调新方法。该方法在考虑各组子带信号能量大小的基础上,按修正的归一化峭度(MKv)最大化准则自动选择一组含有丰富故障信息的子带信号进行Hil-bert包络谱分析提取故障特征。利用该方法对仿真和实际轴承故障信号进行了解调分析,分析结果表明,该方法可以有效地检测出轴承故障。

关键词：滤波器组振动信号解调故障检测

Förster resonance energy transfer reveals phillygenin and swertiamarin concurrently target AKT on different binding domains to increase the anti-inflammatory effect

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Chinese Chemical Letters 2024年第5期35卷 207-212页

作者： Xiaoyao Ma Jinling Zhang Ge Fang he Gao Jie Gao Li fu Yuanyuan Hou Gang Bai State Key Laboratory of Medicinal Chemical Biology College of Pharmacy and Tianjin Key Laboratory of Molecular Drug ResearchNankai UniversityTianjin 300000China College of Life health Dalian UniversityDalian 116622China Dalian fusheng Pharmaceutical Co. Ltd.Dalian 116000China

The clinical benefit of combination therapy is significant,but it is not easy to define the mechanism of complexity and *** studies illustrate that phillygenin(Phi)binds in the allosteric inhibit pocket of protein kinase B(AKT),and swertiamarin(Swe)acts on the pleckstrin homology(PH)domain of ***,the combined synergistic effect of relieving the inflammatory response has yet to be *** on high sensitivity,specificity and fast-responsibility fluorescent sensors,the Förster resonance energy transfer(FRET)technique offers a route to provide clear insights into physiological and pathological *** the study,molecular docking,the fluorescent probes of Phi and Swe for FRET were designed and *** analysis shown that Swe and Phi concurrently acted on the PH domain and allosterically inhibited pocket of AKT,*** combination of Swe and Phi significantly increased the heat stability of AKT and decreased protease-induced *** lipopolysaccharides(LPS)-induced mice and cells,the combination arrested AKT activation,nuclear factor kappa-B(NF-κB)phosphorylation,and the expression of tumor necrosis factor-α(TNF-α),interleukin(IL)-6 and *** conclusion,FRET revealed Phi and Swe concurrently targeted AKT on different domains and the combination of Phi and Swe enhanced the anti-inflammatory effect.

关键词： FRET Swertiamarin Phillygenin AKT Anti-inflammation Combinatorial drug

Microstructural evolution,mechanical properties and degradation mechanism of PS-PVD quasi-columnar thermal barrier coatings exposed to glassy CMAS deposits

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Rare Metals 2024年第7期43卷 3329-3340页

作者： Zi-Yue Yu Liang-Liang Wei Xing-Ye Guo Bao-Peng Zhang qing he Hong-Bo Guo School of Materials Science and Engineering Beihang UniversityBeijing100191China Key Laboratory of High-Temperature Structure Materials and Protective Coatings(Ministry of Industry and Information Technology) Beihang UniversityBeijing 100191China Surface Engineering Research Institute Chinese Academy of Agricultural Mechanization SciencesBeijing 100083China

Thermal barrier coatings(TBCs) applied in aeroengines tend to be attacked by molten calcia-magnesiaalumino-silicate(CMAS) at high operating ***-stabilized zirconia(YSZ) coatings with quasicolumnar microstructure were fabricated by plasma spray physical vapor deposition(PS-PVD) *** chemic al changes,micros tructural transform ation,mechanical properties and degradation mechanisms of the CM AS-interacted TBCs in the thermal cycling tests were *** YSZ grains were dissolved in the CMAS melts,and then the ZrO_(2) grains were reprecipitated with spherical shape,accompanying with phase transformation from tetragonal(t) to monoclinic(m).The thermal cycling tests reveal that the YSZ coating fails at the early stage due to the attack of *** fractures in intracolumns lead to partial spallation of the *** failure of the coating occurs at the interfaces between thermally grown oxides(TGO) layer and YSZ topcoat;especially,the hardness and Young's modulus of the YSZ coatings increase intensively,as the coatings were infiltrated by the CMAS for a long time.

关键词： CMAS Thermal barrier coatings Young's modulus Thermal cycling behavior PS-PVD

3D printing encouraging desired in-situ polypyrrole seed-polymerization for ultra-high energy density supercapacitors

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Journal of Energy Chemistry 2024年第8期95卷 117-125,I0004页

作者： Tiantian Zhou Shangwen Ling Shuxian Sun Ruoxin Yuan Ziqin Wu Mengyuan fu Hanna he Xiaolong Li Chuhong Zhang State Key Laboratory of Polymer Materials Engineering Polymer Research InstituteSichuan UniversityChengdu 610065SichuanChina

The tireless pursuit of supercapacitors with high energy density entails the parallel advancement of wellsuited electrode materials and elaborately engineered ***(PPy)emerges as an exceedingly conductive polymer and a prospective pseudocapacitive materials for supercapacitors,yet the inferior cyclic stability and unpredictable polymerization patterns severely impede its real-world ***,for the first time,an innovative seed-induced in-situ polymerization assisted 3D printing strategy is proposed to fabricate PPy-reduced graphene oxide/poly(vinylidene difluoride-cohexafluoropropylene)(PVDF-HFP)(PPy-rGO/PH)electrodes with controllable polymerization behavior and exceptional areal mass *** preferred active sites uniformly pre-planted on the 3D-printed graphene substrates serve as reliable seeds to induce efficient polypyrrole deposition,achieving an impressive mass loading of 185.6 mg cm^(-2)(particularly 79.2 mg cm^(-2)for polypyrrole)and a superior areal capacitance of 25.2 F cm^(-2)at 2 mA cm^(-2)for a 12-layer *** agreement with theses appealing features,an unprecedented areal energy density of 1.47 mW h cm^(-2)for a symmetrical device is registered,a rarely achieved value for other PPy/rGO-based *** work highlights a promising route to preparing high energy density energy storage modules for real-world applications.

关键词： 3D printing Seed-induced polymerization Supercapacitor Polypyrrole High energy density

Nanocomposite: Keggin-type Co_(4)-polyoxometalate@cobaltporphyrin linked graphdiyne for hydrogen evolution in seawater

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Nano Research 2024年第3期17卷 1281-1287页

作者： Jiejie Ping Danyang he Fei Wang Nan Wang Yi-cheng fu Zihao Xing Zhiyu Jia Guo-Yu Yang Key Laboratory of Cluster Science Ministry of EducationSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Facluty of Chmeistry Northeast Normal UniversityChangchun 130024China Peking University Third Hospital Beijing 100190China

Polyoxometalate-based nanocomposites with electrocatalytic activity have been applied in hydrogen evolution reactions(heR).Seawater as the main water resource on the earth should be developed as the water electrolysis to prepare high-purity *** this paper,we used two synthesis strategies to prepare the nanocomposite Co_(4)-POM@Co-PGDY(Co_(4)-POM:the Kegging-type microcrystals of K_(10)[Co_(4)(PW_(9)O_(3)4)2]and Co-PGDY:cobalt-porphyrin linked graphdiyne)with excellent activity for ***-PGDY as the porous material is applied not only as the protection of microcrystals towards the metal ion in seawater but also as the co-electrocatalyst of Co_(4)-***_(4)-POM@Co-PGDY exhibits excellent heR performance in seawater electrolytes with low overpotential and high stability at high ***,we have observed a key H_(3)O+intermediate emergence on the surface of nanocomposite during hydrogen evolution process in seawater by Raman synchrotron radiation-based Fourier transform infrared(SR-FTIR).The results in this paper provide an effective strategy for preparing polyoxometalate-based electrocatalysts with high-performance toward hydrogen evolution reaction.

关键词： polyoxometalate graphdiyne seawater hydrogen evolution reaction

Facile synthesis of NiMn2S4 nanoflakes on nickel foam for high-performance aqueous asymmetric supercapacitors

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Science China(Technological Sciences) 2024年第2期67卷 499-508页

作者： ADIL Emin LI YaLi GAO Zhe DONG YunXia LI DongHao CheN YongChao fu YuJun he DeYan LI JunShuai LONGi Institute of future Technology and School of Materials&EnergyLanzhou UniversityLanzhou 730000China

Supercapacitors display promising electrochemical performance with high power density and excellent cycle ***,their low energy density limits their advancement in a broader range of *** enhance their energy density,we proposed self-assembled spinel NiMn2S4nanoflakes grown on nickel foam which we successfully prepared by a facile hydrothermal *** NiMn2S4electrode delivers a high capacitance of 2096.7 F g^(-1)at 1.0 A g^(-1),with an exceptional rate capability(~720.6 F g^(-1)at a very high current density of 100 A g^(-1))and good cycle stability(~85.1%retention of the initial capacitance after 7000 cycles with the Coulombic efficiency around 100%).The as-fabricated asymmetric supercapacitors based on NiMn2S4nanoflakes//active carbon demonstrate an energy density of 73.6 W h kg^(-1)at 800.5 W kg^(-1)and adequate cycling performance of~84.6%capacitance retention at 15 A g^(-1)after 10000 *** results reveal that the nanostructured NiMn2S4is an excellent electrode material for high-performance energy storage applications.

关键词： NiMn2S4 nanostructure high capacitance aqueous supercapacitors long cycle stability high energy density

A novel alternative for pyrogen detection based on a transgenic cell line

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Signal Transduction and Targeted Therapy 2024年第3期9卷 1221-1229页

作者： qing he Chuan-Fei Yu Gang Wu Kai-Qin Wang Yong-Bo Ni Xiao Guo Zhi-Hao fu Lan Wang De-Jiang Tan Hua Gao Can Wang Gang Chen Xu-Hong Chen Bo Chen Jun-Zhi Wang National Institutes for Food and Drug Control BeijingChina School of Life Science and Biopharmaceutics Shenyang Pharmaceutical UniversityShenyangChina Shanghai Institute for Food and Drug Control ShanghaiChina KeyMed Biosciences Inc. ChengduChina

Pyrogen,often as a contaminant,is a key indicator affecting the safety of almost all parenteral drugs(including biologicals,chemicals,traditional Chinese medicines and medical devices).It has become a goal to completely replace the in vivo rabbit pyrogen test by using the in vitro pyrogen test based on the promoted‘reduction,replacement and refinement’principle,which has been highly considered by regulatory agencies from different *** used NF-κB,a central signalling molecule mediating inflammatory responses,as a pyrogenic marker and the monocyte line THP-1 transfected with a luciferase reporter gene regulated by NF-κB as an in vitro model to detect pyrogens by measuring the intensity of a fluorescence ***,we show that this test can quantitatively and sensitively detect endotoxin(lipopolysaccharide from different strains)and nonendotoxin(lipoteichoic acid,zymosan,peptidoglycan,lectin and glucan),has good stability in terms of NF-κB activity and cell phenotypes at 39 cell passages and can be applied to detect pyrogens in biologicals(group A&C meningococcal polysaccharide vaccine;basiliximab;rabies vaccine(Vero cells)for human use,freeze-dried;Japanese encephalitis vaccine(Vero cells),inactivated;insulin aspart injection;human albumin;recombinant human erythropoietin injection(CHO Cell)).The within-laboratory reproducibility of the test in three independent laboratories was 85%,80%and 80%and the interlaboratory reproducibility among laboratories was 83.3%,95.6%and 86.7%.The sensitivity(true positive rate)and specificity(true negative rate)of the test were 89.9%and 90.9%,*** summary,the test provides a novel alternative for pyrogen detection.

关键词： pyrogen rabbit replace

Establishing and clinically validating a machine learning model for predicting unplanned reoperation risk in colorectal cancer

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World Journal of Gastroenterology 2024年第23期30卷 2991-3004页

作者： Li-Qun Cai Da-qing Yang Rong-Jian Wang he Huang Yi-Xiong Shi Department of Colorectal and Anal Surgery Whenzhou Central HospitalWenzhou 325000Zhejiang ProvinceChina Department of Colorectal and Anorectal Surgery The First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina

BACKGROUND Colorectal cancer significantly impacts global health,with unplanned reoperations post-surgery being key determinants of patient *** predictive models for these reoperations lack precision in integrating complex clinical *** To develop and validate a machine learning model for predicting unplanned reoperation risk in colorectal cancer *** Data of patients treated for colorectal cancer(n=2044)at the First Affiliated Hospital of Wenzhou Medical University and Wenzhou Central Hospital from March 2020 to March 2022 were retrospectively *** were divided into an experimental group(n=60)and a control group(n=1984)according to unplanned reoperation *** were also divided into a training group and a validation group(7:3 ratio).We used three different machine learning methods to screen characteristic variables.A nomogram was created based on multifactor logistic regression,and the model performance was assessed using receiver operating characteristic curve,calibration curve,Hosmer-Lemeshow test,and decision curve *** risk scores of the two groups were calculated and compared to validate the *** More patients in the experimental group were≥60 years old,male,and had a history of hypertension,laparotomy,and hypoproteinemia,compared to the control *** logistic regression analysis confirmed the following as independent risk factors for unplanned reoperation(Phesiologists *** operating characteristic curve analysis showed that the model had good discrimination and clinical *** This study used a machine learning approach to build a model that accurately predicts the risk of postoperative unplanned reoperation in patients with colorectal cancer,which can improve tr

关键词： Colorectal cancer Postoperative unplanned reoperation Unplanned reoperation Clinical validation Nomogram Machine learning models

Dynamically switchable porphyrin-based molecular tweezer for on-off fullerene recognition

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Chinese Chemical Letters 2024年第6期35卷 283-287页

作者： Zhimin Sun Xin-Hui Guo Yue Zhao qing-Yu Meng Li-Juan Xing he-Lue Sun College of Chemistry and Materials Science Hebei Key Laboratory of Organic Functional MoleculesHebei Normal UniversityShijiazhuang 050024China

herein,a novel molecular tweezer based on 2,2'-bipyridine-bridged porphyrin subunits was constructed for efficient fullerenes *** syn conformation of the molecule,which was obtained by Zn(Ⅱ)coordination,gives rise to a proper cavity to interact with fullerene guests to form a stable 1:1 complex in toluene *** exhibits distinct binding selectivity towards C_(60)over C_(70).Moreover,the fullerene recognition capacity can be adequately suppressed by importing H_(2)PO_(4)^(-)to competitively capture Zn(Ⅱ)along with syn-anti conformational ***,the molecular tweezer regenerated to bind the fullerene by introducing the Ca^(2+)into the ***,the association-disassociation process can be switched reversibly and repeatedly.

关键词： Molecular tweezer fullerene recognition Supramolecular chemistry Conformation conversion Coordination