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Acta Mechanica Sinica 2015年第3期31卷 406-415页

作者： Yilong Liu achim fischer Peter Eberhard Baohai Wu Key Laboratory of Contemporary Design and Integrated Manufacturing Technology Northwestern Polytechnical University Institute of Engineering and Computational Mechanics University of Stuttgart

A high-order full-discretization method （FDM） using Hermite interpolation （HFDM） is proposed and implemented for periodic systems with time delay. Both Lagrange interpolation and Hermite interpolation are used to approximate state values and delayed state values in each discretization step. The transition matrix over a single period is determined and used for stability analysis. The proposed method increases the approximation order of the semidiscretization method and the FDM without increasing the computational time. The convergence, precision, and efficiency of the proposed method are investigated using several Mathieu equations and a complex turning model as examples. Comparison shows that the proposed HFDM converges faster and uses less computational time than existing methods.

关键词： Full-discretization method Time delay -Stability Chatter

Stability analysis of a thin-walled cylinder in turning operation using the semi-discretization method

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Acta Mechanica Sinica 2014年第2期30卷 214-222页

作者： Arnab Chanda achim fischer Peter Eberhard Santosha Kumar Dwivedy Institute of Engineering and Computational Mechanics University of Stuttgart

In this work, the stability of a flexible thin cylindrical workpiece in turning is analyzed. A process model is derived based on a finite element representation of the workpiece flexibility and a nonlinear cutting force law. Repeated cutting of the same surface due to overlapping cuts is modeled with the help of a time delay. The stability of the so obtained system of periodic delay differential equations is then determined using an approximation as a time-discrete system and Floquet theory. The time-discrete system is obtained using the semi-discretization method. The method is implemented to analyze the stability of two different workpiece models of different thicknesses for different tool positions with respect to the jaw end. It is shown that the stability chart depends on the tool position as well as on the thickness.

关键词： Machine tools Stability Chatter

Improving the dynamic stability of a workpiece dominated turning process using an adaptronic tool holder

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Theoretical & Applied Mechanics Letters 2013年第1期3卷 63-70页

作者： achim fischer Peter Eberhard Institute of Engineering and Computational Mechanics University of Stuttgart

In this contribution, inside turning of a thin-walled cylinder is investigated in simulation. Self-excited vibrations can arise due to repeated cutting of the same surface, that lead to instability.A flexible multibody system model of the system is the basis for a subsequent analysis of the stability of the process. Stability analysis is done using an approximation as a time-discrete system via the semi-discretization method. An adaptronic turning chisel comprising a piezo actuator and sensors is then used in combination with different control concepts to improve the stability of the process. The effectiveness of the different strategies is compared based on the influence on the stability charts. A classic H∞ controller based on a model of the coupled system of workpiece and tool can only yield some improvements, when an additional measurement of the workpiece displacement is added. Incorporating knowledge on the cutting process coupling workpiece and tool using a gain scheduled H∞ controller allows further improvements. However, robustness with respect to model uncertainties, notably concerning the force law, remains an issue. C 2013 The Chinese Society of Theoretical and Applie-d Mechanics. [doi：10.1063/2.1301308]

关键词： multibody dynamics vibrations stability feedback control

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Mo基复合金属氧化物催化丙烷氧化制丙烯醛

石油化工 2006年第8期35卷 730-734页

作者：宋振陆维敏朱艺涵 achim fischer 浙江大学催化研究所浙江杭州310028 德固赛股份公司

制备了Mo基复合金属氧化物(MoMxOn,M=C r,Co,Zn,Mn,Nb,Ce)催化剂,评价了不同金属含量的MoMxOn催化剂在不同温度下对丙烷选择性氧化制备丙烯醛反应的催化性能。在所研究的各种MoMxOn催化剂中,MoCo0.1On催化剂在773 K时的催化性能最佳,丙... 详细信息

制备了Mo基复合金属氧化物(MoMxOn,M=C r,Co,Zn,Mn,Nb,Ce)催化剂,评价了不同金属含量的MoMxOn催化剂在不同温度下对丙烷选择性氧化制备丙烯醛反应的催化性能。在所研究的各种MoMxOn催化剂中,MoCo0.1On催化剂在773 K时的催化性能最佳,丙烯醛的收率为9.3%。Raman光谱和X射线衍射表征结果表明,除MoNbxOn催化剂外,其他各种MoMxOn催化剂中的主要物相是MoO3,说明MoO3可能对催化活性起重要作用。增加Co含量使MoO3衍射峰的相对强度发生改变,可能是引起MoCoxOn催化剂氧化性能下降的原因。

关键词：丙烷丙烯醛钼复合金属氧化物催化剂选择性氧化

Rising utilization of stable isotopes in tree rings for climate change and forest ecology

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Journal of Forestry Research 2024年第1期35卷 103-116页

作者： Ru Huang Chenxi Xu Jussi Grießinger Xiaoyu Feng Haifeng Zhu achim Bräuning National Institute of Natural Hazards Beijing 100085People’s Republic of China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029People’s Republic of China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044People’s Republic of China Institute of Geography Friedrich-Alexander-University of Erlangen-Nuremberg91058 ErlangenGermany State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Analyses of stable isotopes(C,O,H)in tree rings are increasingly important cross-disciplinary *** rapid development in this field documented in an increasing number of publications requires a comprehensive *** study includes a bibliometric analysis-based review to better understand research trends in tree ring stable isotope ***,1475 publications were selected from the Web of Science Core Collection for *** findings are that:(1)numbers of annual publications and citations increased since *** 1974 to 1980,there were around two relevant publications per ***,from 2020 to 2022,this rose sharply to 109 publications per ***,average article citations were less than four per year before 1990,but were around four per article per year after 2000;(2)the major subjects using tree ring stable isotopes include forestry,geosciences,and environmental sciences,contributing to 42.5%of the total during 1974-2023;(3)the top three most productive institutions are the Chinese Academy of Sciences(423),the Swiss Federal Institute for Forest,Snow and Landscape Research(227),and the University of Arizona(204).These achievements result from strong collaborations;(4)review papers,for example,(Dawson et al.,Annu Rev Ecol Syst 33:507-559,2002)and(McCarroll and Loader,Quat Sci Rev 23:771-801,2004),are among the most cited,with more than 1000 citations;(5)tree ring stable isotope studies mainly focus on climatology and ecology,with atmospheric CO_(2) one of the most popular *** 2010,precipitation and drought have received increasing *** on this analysis,the research stages,key findings,debated issues,limitations and direc-tions for future research are *** study serves as an important attempt to understand the progress on the use of stable isotopes in tree rings,providing scientific guid-ance for young researchers in this field.

关键词： Tree rings Stable isotopes Web of Science Bibliometric

Development and characterization of 3D-printed electroconductive pHEMA-co-MAA NP-laden hydrogels for tissue engineering

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Bio-Design and Manufacturing 2024年第3期7卷 262-276页

作者： Sara De Nitto Aleksandra Serafin Alexandra Karadimou achim Schmalenberger John J.EMulvihill Maurice N.Collins DIBRIS Polytechnic Inter-School Section University of Genoa16126 GenoaItaly School of Engineering Bernal InstituteUniversity of LimerickLimerick V94 T9PXIreland School of Natural Sciences Department of Biological SciencesUniversity of LimerickLimerick V94 T9PXIreland Health Research Institute University of LimerickLimerick V94 T9PXIreland AMBER University of LimerickLimerick V94 T9PXIreland

Tissue engineering(TE)continues to be widely explored as a potential solution to meet critical clinical needs for diseased tissue replacement and tissue *** this study,we developed a poly(2-hydroxyethyl methacrylate-co-methacrylic acid)(pHEMA-co-MAA)based hydrogel loaded with newly synthesized conductive poly(3,4-ethylene-dioxythiophene)(PEDOT)and polypyrrole(PPy)nanoparticles(NPs),and subsequently processed these hydrogels into tissue engineered constructs via three-dimensional(3D)*** presence of the NPs was critical as they altered the rheological properties during ***,all samples exhibited suitable shear thinning properties,allowing for the development of an optimized processing window for 3D *** were 3D printed into pre-determined disk-shaped configurations of 2 and 10 mm in height and diameter,*** observed that the NPs disrupted the gel crosslinking efficiencies,leading to shorter degradation times and compressive mechanical properties ranging between 450 and 550 *** conductivity of the printed hydrogels increased along with the NP concentration to(5.10±0.37)×10^(−7)S/*** vitro studies with cortical astrocyte cell cultures demonstrated that exposure to the pHEMA-co-MAA NP hydrogels yielded high cellular viability and proliferation ***,hydrogel antimicrobial studies with staphylococcus epidermidis bacteria revealed that the developed hydrogels affected bacterial *** together,these materials show promise for various TE strategies.

关键词： Conductive nanoparticles Hydroxyethyl methacrylate(HEMA) Ultraviolet(UV)polymerization 3D printing

Mo基多组分催化剂催化丙烷选择氧化制丙烯醛

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浙江大学学报（理学版） 2009年第4期36卷 423-429页

作者：李晗陆维敏宋振朱艺涵 fischer achim 浙江大学催化研究所浙江杭州310028 德国EvonicDegussa股份有限公司 Hanau-Wolfgang63457

用共沉淀法制备了不同比例的MoCrTeO、MoCoTeO和MoCrTeCoO复合氧化物催化剂,考察其对丙烷选择氧化制丙烯醛反应的催化性能,并对反应温度、空速、原料气比例等条件进行优化,得到丙烯醛最高产率为22.96%.实验结果表明,Te元素的添加对提高... 详细信息

用共沉淀法制备了不同比例的MoCrTeO、MoCoTeO和MoCrTeCoO复合氧化物催化剂,考察其对丙烷选择氧化制丙烯醛反应的催化性能,并对反应温度、空速、原料气比例等条件进行优化,得到丙烯醛最高产率为22.96%.实验结果表明,Te元素的添加对提高丙烯醛的选择性和产率起了十分重要的作用,但过高的Te含量却不利于丙烷的转化率.X射线衍射表征结果表明,催化剂中正交系TeMo5O16相可能是丙烷选择氧化制丙烯醛反应的重要的活性相.

关键词：丙烷丙烯醛催化选择氧化 MoCrTeCoO催化剂

追求卓越向“智”而行——访德国HAINBUCH瀚柏格夹具集团首席执行官achim Feinauer博士

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现代制造 2024年第S1期 24-26页

作者：张欣 achim Feinauer 不详德国HAINBUCH瀚柏格夹具集团

在高精度、高效率以及不断增长的柔性自动化需求的生产环境中,工件夹具的重要性日益凸显。随着行业转型升级步伐加快,多品种小批量生产乃至多品种大批量生产规模的需求快速增长,用户群体愈加重视夹具的选型和管理,这进一步对工装夹具提... 详细信息

在高精度、高效率以及不断增长的柔性自动化需求的生产环境中,工件夹具的重要性日益凸显。随着行业转型升级步伐加快,多品种小批量生产乃至多品种大批量生产规模的需求快速增长,用户群体愈加重视夹具的选型和管理,这进一步对工装夹具提出了更高的要求和挑战,带动了夹具的快速发展与创新。

关键词：多品种小批量生产柔性自动化工装夹具工件夹具大批量生产首席执行官追求卓越

Anesthetic Management of a Patient with Spinal Muscular Atrophy Type III Undergoing Emergent Caesarean Section: A Case Report

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Open Journal of Anesthesiology 2024年第6期14卷 151-158页

作者： Kwame Awuku achim Younker Breta Osei-Bonsu Joseph Nalbone Aditi Master Dongchen Li Ming Xiong Rutgers New Jersey Medical School Newark New Jersey USA

In this case report, we describe the anesthetic management for a 36-year-old G2P0010 at 36 weeks gestation with Spinal Muscular Atrophy Type III who underwent an emergent caesarean section due to fetal footling breech position. The patient is a wheelchair-bound quadriplegic with kyphoscoliosis and a lack of cough reflex who required nasal continuous noninvasive ventilatory support (CNVS) for chronic hypercapnic respiratory failure. Surgery was done under general anesthesia due to its emergent nature, and the patient was successfully extubated and transitioned to nasal CNVS in the operating room at the end of the case. Postoperative care was provided in the medical intensive care unit for three days without complication and the patient was discharged home uneventfully.

关键词： Spinal Muscular Atrophy General Anesthesia Cesarean Section Obstetric Anesthesia

Treatment and prevention of epilepsy in onchocerciasis-endemic areas is urgently needed

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Infectious Diseases of Poverty 2024年第1期13卷 85-89页

作者： Robert Colebunders Joseph Nelson Siewe Fodjo Olivia Kamoen Luis-Jorge Amaral Amber Hadermann Chiara Trevisan Mark J.Taylor Julia Gauglitz achim Hoerauf Yasuaki Sato Katja Polman Maria-Gloria Basanez Dan Bhwana Thomson Lakwo Gasim Abd-Elfarag Sebastien D.Pion Global Health Institute University of AntwerpAntwerpBelgium Department of Neurology Heilig Hart ZiekenhuisLierBelgium Department of Public Health Institute of Tropical MedicineAntwerpBelgium Liverpool School of Tropical Medicine LiverpoolUK Department of Computer Science University of AntwerpAntwerpBelgium Institute of Medical Microbiology Immunology and ParasitologyUniversity Hospital BonnBonnGermany German Center for Infection Research(DZIF) Partner Site Bonn-CologneBonnGermany School of Global Humanities and Social Sciences Nagasaki UniversityNagasakiJapan MRC Centre for Global Infectious Disease Analysis and London Centre for Neglected TropicalDisease Research Department of Infectious Disease EpidemiologySchool of Public HealthImperial College LondonLondonUK National Institute for Medical Research TangaTanzania Vector Control Division Ministry of HealthKampalaUganda School of Public Health University of JubaJubaSouth Sudan Access for Humanity JubaSouth Sudan French National Research Institute for Sustainable Development MontpellierFrance

Background There is increasing epidemiological evidence supporting the association between onchocerciasis and seizures, reinforcing the concept of onchocerciasis-associated epilepsy (OAE). The aim of this paper is to provide an update on the new knowledge about OAE and to propose recommendations to the World Health Organization how to address this public health *** text During the 2nd International Workshop on OAE held on 19-21 September, 2023, in Antwerp, Belgium, participants recognised OAE as a substantial yet neglected public health problem, particularly in areas of sub-Saharan Africa where onchocerciasis remains hyperendemic. Evidence from prospective population-based studies suggest that strengthening onchocerciasis elimination efforts leads to a significant reduction of OAE incidence. There is a need to validate an OAE case definition to estimate the burden of disease and identify onchocerciasis-endemic areas requiring intensification of onchocerciasis elimination programmes and integration of epilepsy care. It is expected that raising awareness about OAE will boost the population uptake of ivermectin. The implementation of a community-based epilepsy treatment programme offering free anti-seizure medications (ASMs) has shown high effectiveness in reducing the frequency of seizures and improving the overall quality of life of people with *** To reduce OAE burden, enhanced collaboration between onchocerciasis and mental health programmes at community, national, and international levels is required. Urgent efforts are needed to ensure the uninterrupted provision of free ASMs in onchocerciasis-endemic areas. Furthermore, OAE should be included in the quantification of the onchocerciasis disease burden.

关键词： Onchocerciasis Morbidity Burden of disease Prevention Ivermectin Epilepsy Nodding syndrome Treatment Children Policy