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Finite boundary effects in problem of a crack perpendicular to and terminating at a bimaterial interface

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Acta Mechanica Sinica 2005年第1期21卷 56-64页

作者： ShaohuaChen tzuchiangWang SharonKao-walter LNM InstituteofMechanicsChineseAcademyofSciencesBeijing100080China DepartmentofMechanicalEngineering BlekingeInstituteofTechnologyS-37179KarlskronaSweden

In this paper, the problem of a crack perpendicular to and terminating at an interface in bimaterial structure with finite boundaries is investigated. the dislocation simulation method and boundary collocation approach are used to derive and solve the basic equations. two kinds of loading form are considered when the crack lies in a so.ter or a stiffer material, one is an ideal loading and the other one fits to.the practical experiment loading. Complete solutions of the stress field including the t stress are o.tained as well as the stress intensity factors. Influences of t stress on the stress field ahead of the crack tip are studied. Finite boundary effects on the stress intensity factors are emphasized. Comparisons with the problem presented by Chen et al. (Int. J. Solids and Structure, 2003, 40, 2731–2755) are discussed also.

关键词： Bimaterial structure Finite boundary Crack Stress intensity factor t stress

Experimental and calculated liquid-liquid interfacial tension in demixing metal alloys

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Rare Metals 2006年第5期25卷 452-456页

作者： walter Hoyer Ivan Kaban Institute of Physics Chemnitz University of Technology D-09107 ChemnitzGermany

Liquid-liquid interracial tension in binary and temary Al-based monotectic systems has been determined experimentally with a tensiometric method in a wide temperature interval. the temperature dependence of the interfacial tension is well described by a power law function of the type σαβ - （1 - t/tc）δ with the critical exponent δ= 1.3 and a critical temperature tc. theoretical models describing the liquid-liquid interface in monotectic alloys and their applicability for calculation of the interfacial tension and its temperature dependence in binary systems are considered.

关键词： immiscible systems Al-based alloys interracial tension

A Unisonant r-Matrix Structure of Integrable Systems and Its Reductions

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Chinese Physics Letters 2000年第4期17卷 235-237页

作者： QIAo Zhi-Jun walter StRAMPP Institute of Mathematics Fudan UniversityShanghai 200433 Fachbereich 17 Mathematikj Universitat-GH KasselD-34109 KasselGermany

A new method is presented to generate finite dimensional integrable *** starting point is a generalized Lax matrix instead of usual Lax *** a unisonant r-matrix structure and a set of generalized Hamiltonian functions are *** can be clearly seen that various constrained integrable Hows by nonlinearization method,such as the c-AKNS,c-MKdV,c~toda,etc.,are derived from the reduction of this ***,some new integrable Hows are produced.

关键词： structure integrable matrix

Indentation Size Effect inβCuAlBe and Cu-2Be Alloys

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Acta Metallurgica Sinica(English Letters) 2021年第12期34卷 1669-1678页

作者： Susana Mo.tecinos Sebastian tognana walter Salgueiro IFIMAt Facultad de Ciencias ExactasUniversidad Nacional del Centro de La Provincia de Buenos AiresPinto 3997000 TandilArgentina Consejo Nacional de Investigaciones Científicas y técnicas CoNICEt Av.Rivadavia 1917C1033AAJ Buenos AiresArgentina CIFICEN(UNCPBA-CICPBA-CoNICEt) Pinto 3997000 TandilArgentina Comisión de Investigaciones Científicas de la Provincia de Bs.As Calle 526 entre 10 y 111900 La PlataArgentina

the indentation size effect(ISE)was studied by instrumented nanoindentation and Vickers hardness measurements on polycrystalline copper,βCuAlBe pseudoelastic and age-hardenable CuBe *** in the load-depth curves at different loads would suggest a change in the behavior of the materials as the load *** was estimated at different loads taking into account the pile-up in each case,which was estimated from the images of the topography o.tained by atomic force microscopy(AFM).the effect of the micro.tructure of Cu-2Be(wt%)samples on the ISE was also *** each copper alloy,the Nix and Gao model was applied to.the hardness-depth curves,and significant differences were found for the parameters *** is in the constant nanohardness regime for depths below 500 nm,while microhardness exhibits the ISE *** behavior of the nanohardness and the plastic strain with the depth is almo.t *** presents the lowest values of plastic strains due to.the pseudoelastic effect,while Cu presents an almo.t constant value around 8%,which corresponds to.the highest plastic strain o.tained.

关键词： Hardness Pseudoelasticity Copper alloys Plasticity Indentation size effect

Normal families and fixed points of iterates

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Science China Mathematics 2010年第3期53卷 593-596页

作者： BERGWEILER walter Mathematisches Seminar der Christian–Albrechts–Universitt zu Kiel

Let F be a family of holomorphic functions and suppose that there exists ε > 0 such that if f ∈ F, then |(f 2 ) (ξ)|≤4-ε for all fixed points ξ of the second iterate f 2 . We show that then F is normal. this is deduced from a result which says that if p is a polynomial of degree at least 2, then p 2 has a fixed point ξ such that |(p 2 ) (ξ)|≥4. the results are motivated by a problem posed by Yang Lo.

关键词： fixed point multiplier normality iteration periodic point

the secrets to running economy

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Journal of Spo.t and Health Science 2022年第3期11卷 273-274页

作者： walter Herzog Human Performance Laboratory Faculty of KinesiologyUniversity of CalgaryCalgaryAB T2N 1N4Canada

Every once in a while,a spo.t is revolutionized by a discovery or a new *** the mid-1980s,cross-country skiing was changed forever by the introduction of the skating *** Fosbury revolutionized high-jumping when he won the olympic Games by crossing the bar“backwards”,and the development of the“klapp-skate”led to vast improvements of world records in speed skating.

关键词： technique. backward revolution

Reflections on obesity,exercise,and musculoskeletal health

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Journal of Spo.t and Health Science 2020年第2期9卷 108-109页

作者： walter Herzog Guest Editor Human Performance Laboratory Faculty of KinesiologyUniversity of CalgaryCalgaryAB T2N1N4Canada

obesity is a disease that has become an epidemic in economically developed countries,and manifests itself at increasing rates in economically developing *** is associated with a variety of comorbidities,such as metabolic disease,diabetes,cardiovascular diseases,and musculoskeletal disorders,all resulting in tremendous co.ts to health care systems around the world,a reduced capacity for work,and reduced quality of life for people with obesity,coupled with physical inactivity,thereby producing a vicious circle of inactivity-induced diseases that enhances obesity.

关键词： obesity skeletal thereby

Effect of Bio.timulants Based on Natural Products on the Gro.th and Nutritional Value of Bean (Phaseolus vulgaris L.)

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American Journal of Plant Sciences 2024年第7期15卷 492-518页

作者： Aimé Giresse tzeuton Flore Eliane Eyenga Arouna Meshuneke Gaston Mbang Elock Fabrice Damien Wassom walter Jospin timma Kom Marie Paule Djam Kengoum Erica Cabrelle Damtse Damtse Landry Silatsa Fotsing William Asah Che Marlyne Josephine Mananga Nicolas Niemenak Cécile Annie Ewané Laboratory of Plant Physiology and Biochemistry Higher Teachers Training College University of Yaound 1 Yaound Cameroon Department of Biochemistry Faculty of Sciences University of Yaound 1 Yaound Cameroon Laboratory of Food Sciences and Metabolism University of Yaoundé 1 Yaoundé Cameroon Laboratory of Phytoprotection and Valorisation of Genetic Resources of the Biotechnology Centre University of Yaound 1 Yaound Cameroon Department of Biological Sciences Higher Teachers Training College University of Yaound 1 Yaound Cameroon

Beans (Phaseolus vulgaris L.) are widely grown in Cameroon and play a key role in the fight against food insecurity, malnutrition and poverty. However, its cultivation encounters problems due to abiotic and biotic stresses, which leads to.the use of synthetic fertilizers and pesticides, which cause significant damage to.the environment and human health due to.the presence of synthetics residues in the seeds, pods and in the leaves that are eaten. Promoting the use of natural products is becoming a necessity for organic and eco-responsible agriculture that limits co.tamination problems and improves people’s purchasing power. this study aims to assess the effect of bio.timulants based on natural products on the gro.th and nutritional value of common bean (Phaseolus vulgaris L.). Bean seedlings from white variety (MEX-142) and red variety (DoR-701) were treated every seven days in the field from their pre-emergence, emergence and gro.th to.their maturation under a randomized block experimental design. Six treatments and three repetitions with the bio.timulants based on natural products and co.trols were thus performed and the agromorphological parameters were measured. After 120 days, the co.tents of gro.th biomarkers and defense-related enzymes were evaluated in leaves, while the co.tents of macromolecules, minerals and antinutrients were evaluated in seeds. these bio.timulants significantly increased (P P of antinutrients including oxalates, phytates, tannins and saponins in seeds compared to co.trols (t+ and t−). treatment with bio.timulants, in particular BS4, improves the performance of bean plants in the field as well as the biofo.tification of seeds regardless of the variety.

关键词： Phaseolus vulgaris L. Bio.timulants Biofo.tification Gro.th and Defense Biomarkers Nutritional Value

Mobile stroke care expedites intravenous thrombolysis and endovascular thrombectomy

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Stroke & Vascular Neurology 2022年第3期7卷 209-214页

作者： Matthew t Bender thomas K Mattingly Redi Rahmani Diana Proper walter A Burnett Jason L Burgett Joshua LEsperance Jeremy t Cushman Webster H Pilcher Curtis G Benesch Adam G Kelly tarun Bhalla Department of Neurosurgery University of Rochester Medical CenterRochesterNew YorkUSA Department of Emergency Medicine University of Rochester Medical CenterRochesterNew YorkUSA Department of Neurology University of Rochester Medical CenterRochesterNew YorkUSA

Background the number of mobile stroke programmes has increased with evidence,showing they expedite intravenous *** questions include whether time savings extend to patients eligible for endovascular therapy and impact clinical *** our mobile stroke unit(MSU),based at an academic medical centre in upstate New York,launched in o.tober *** reviewed prospective observational data sets over 26 mo.ths to identify MSU and non-MSU emergency medical service(EMS)patients who underwent intravenous thrombolysis or endovascular thrombectomy for comparison of angiographic and clinical *** over 568 days in service,the MSU was dispatched 1489 times(2.6/day)and transpo.ted 300 patients(20%of dispatches).Intravenous tissue plasminogen activator(tPA)was administered to 57 MSU patients and the average time from 911 call-to.tPA was 42.5 min(±9.2),while EMS transpo.ted 73 patients who received tPA at 99.4 min(±35.7)(ptients(12%)received tPA from 3.5 hours to 4.5 hours since last known well and would likely have been o.tside the window with EMS *** thrombectomy was performed on 21 MSU patients with an average 911 call-to groin puncture time of 99.9 min(±18.1),while EMS transpo.ted 54 patients who underwent endovascular thrombectomy(Et)at 133.0 min(±37.0)(p=0.0002).there was no difference between MSU and traditional EMS in modified Rankin score at 90-day clinic follow-up for patients undergoing intravenous thrombolysis or endovascular thrombectomy,whether assessed as a dichotomous or ordinal *** Mobile stroke care expedited both intravenous thrombolysis and endovascular *** is an ongoing need to show improved functional o.tcomes with MSU care.

关键词： intravenous throm endovascular