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Time Lag Effect of Supply Chain Management on Firm Performance

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Journal of Systems Science and Systems Engineering 2021年第3期30卷 321-338页

作者： Lu Xiao Quan Zhu Xiaolin Xu Christoph Wäger School of Business Nanjing UniversityNanjing210000China Faculty of International Business&Communication Zuyd University of Applied SciencesMaastrichtP.O.Box 634NL-6200 APthe Netherlands University of Göttingen Göttingen37083Germany

The objective of this paper is to identify time lag effect in the relationship between supply chain management and financial *** hypothesize that firms with higher supply chain management capability are associated with higher financial performance and the impact would last *** addition,we introduce two contextual variables,ownership and market orientation,to detect the moderating effect of ownership structure and organizational culture,*** use firm-level empirical data from 1,131 public Chinese manufacturing firms for the 2010–2019 period to investigate the effect and the result shows that there is a two-year time lag effect in the relationship,which means the positive impact of current supply chain management would last for three ***,we find evidence that supply chain management in non-state-owned firms is more efficient and its positive financial impact would last longer than that in state-owned ***,we indicate that market-orientation can’t moderate the relationship between supply chain management and financial performance.

关键词： Supply chain management financial performance time lag effect ownership market orientation

High-resolution ex vivo analysis of the degradation and osseointegration of Mg-xGd implant screws in 3D

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Bioactive Materials 2022年第7期7卷 37-52页

作者： Diana krüger Silvia Galli Berit Zeller-Plumhoff D.C.Florian Wieland Niccolo Peruzzi Bjorn Wiese Philipp Heuser Julian Moosmann Ann Wennerberg Regine Willumeit-Romer Institute of Metallic Biomaterials Helmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht21502Germany University of Malmo Faculty of OdontologyDepartment of ProsthodonticsCarl Gustafs vag 34Klerken20506MalmoSweden Lund University Department of Clinical Sciences LundMedical Radiation PhysicsBarngatan 422242LundSweden Deutsches Elektronen-Synchrotron(DESY) Notkestrasse 8522607HamburgGermany Institute of Materials Physics Helmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht21502Germany University of Gothenburg Institute of OdontologyDepartment of ProsthodonticsMedicinaregatan 12 f41390GoteborgSweden

Biodegradable magnesium(Mg)alloys can revolutionize osteosynthesis,because they have mechanical properties similar to those of the bone,and degrade over time,avoiding the need of removal ***,they are not yet routinely applied because their degradation behavior is not fully *** this study we have investigated and quantified the degradation and osseointegration behavior of two biodegradable Mg alloys based on gadolinium(Gd)at high ***-5Gd and Mg-10Gd screws were inserted in rat tibia for 4,8 and 12 ***,the degradation rate and degradation homogeneity,as well as bone-to-implant interface,were studied with synchrotron radiation micro computed tomography and ***(Ti)and polyether ether ketone(PEEK)were used as controls material to evaluate *** results showed that Mg-5Gd degraded faster and less homogeneously than *** alloys gradually form a stable degradation layer at the interface and were surrounded by new bone *** results were correlated to in vitro data obtained from the same material and *** average bone-to-implant contact of the Mg-xGd implants was comparable to that of Ti and higher than for *** results suggest that both Mg-xGd alloys are suitable as materials for bone implants.

关键词： Magnesium alloys Biodegradable implant Micro-computed tomography degradation rate Degradation homogeneity Ex vivo imaging Ex vivo histology Histology vs.tomography

River Stabilisation by Breach-ramps and Widening

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四川大学学报（工程科学版） 2005年第S1期37卷 34-40页

作者： Markus AUFLEger tobias HAFNER Andreas NIEDERMAYR Iint.of Hydraulic and Water Resources Eng. Technische Universitt MünvhenGermany

Numerous gravel-bed rivers are affected by unceasing degradation problems,mostly caused or in- creased by technical measures *** germany removing the bank fixations is regarded as a concept to dissolve the *** allowing lateral erosion and in consequence river widening the bed load transport ca- pacity will be *** the eroded bank material will serve as additional sediment influx. Nevertheless in some cases additional measures are required for a sustainable stabilization o...

关键词： river widening breach-ramps

Determining short chain fatty acids in sewage sludge hydrolysate: A comparison of three analytical methods and investigation of sample storage effects

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Journal of Environmental Sciences 2014年第4期26卷 926-933页

作者： Victor Ibrahim tobias Hey Karin Jonsson VA SYD SE-201 21 Malmo Sweden Water and Environmental Engineering Department of Chemical Engineering Lund University SE-21100 Lund Sweden

In anaerobic digestion, the production of short-chain fatty acids （SCFAs） can be beneficial or harmful to the overall process, depending on the concentration of accumulated acids. Therefore, the accurate determination of the SCFA concentration in both fresh and stored sludge hydrolysates is important. To select a suitable method for monitoring SCFAs during the anaerobic digestion of sewage sludge, the accuracy of three available analytical methods, including 5 pH point acid titration （TITRA5）, gas chromatography （GC）, and spectrophotometry, were compared in the present study. The results revealed that TITRA5 and GC displayed better agreement in the achieved measurements and higher precision and accuracy than the spectrophotometric assay, as supported by the application of different statistical models. TITRA5 excelled in titrating unfiltered hydrolysate while simultaneously measuring the alkalinity, whereas the GC method provided detailed information on the contribution of different fatty acids to the total acidity. In contrast, the spectrophotometric assay suffered from many forms of interference, depending on the sample＇s matrix. SCFA production followed the pattern of enzymatic reactions and fitted the Michaelis-Menten model. In addition to promoting TITRA5 as an accurate and robust analytical tool for routine SCFA analyses, this comparative study also demonstrated the possibility of storing hydrolysate samples at different temperatures and durations without altering the SCFA measurements.

关键词： five pH point titration gas chromatography spectrophotometry short-chain fatty acids sludge hydrolysis sample storage

Configuration-Sensitive Molecular Sensing on Doped Graphene Sheets

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Nano Research 2010年第7期3卷 472-480页

作者： John Russell Petr král Department of Chemistry University of Illinois at ChicagoChicagoIL 60607USA

We show by molecular dynamics simulations that configuration-sensitive molecular spectroscopy can be realized on optimally doped graphene sheets vibrated by an oscillatory electric *** selectivity of the spectroscopy is achieved by maximizing Coulombic binding between the detected molecule and a specific nest,formed for this molecule on the graphene sheet by substituting selected carbon atoms with boron and nitrogen *** can detect binding of different isomers to the nest from the frequency shifts of selected vibrational modes of the combined *** an illustrative example,we simulate detection of hexanitrostilbene enantiomers in chiral nests formed on graphene.

关键词： Molecular sensing enantiomer graphene functionalization molecular dynamics

Analyzing hydro abrasive erosion in Kaplan turbine:A case study from India

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Journal of Hydrodynamics 2016年第5期28卷 863-872页

作者： Anant kr.RAI Arun KUMAR Alternate Hydro Energy Centre IIT Roorkee

Sediment flow through hydro turbine causes erosion of hydraulic components resulting in drop of turbine efficiency, parti- cularly in hydropower plants of the Himalayan region. The measurement of erosion and monitoring of sediment flow in turbine are major concerns in erosion study. Attempts have been made to study erosion mainly in Pelton and Francis turbines. In this study, a simple and effective method has been presented to measure erosion in a Kaplan turbine of a run-of-river scheme Chilla hydropower plant in foothills of Himalaya. Recent techniques were used to measure sediment parameters like concentration, size, shape and mineral content. A standard erosion model is applied to estimate the erosion in Kaplan turbine blade, runner chamber and draft tube cone. A calibration factor has been proposed to apply the erosion model for site specific conditions. It has been found that the outer trailing edges of the turbine blade and upper rtmner chamber are most erosion prone zones. Sediment analysis revealed that effective operation can reduce erosion in turbine components. The estimated erosion values from model are found to be consistent with measu- red values. Finally, suggestions for design improvements and effective operation of erosion affected hydropower plants are given.

关键词： turbine sediment erosion measurement IEC 62364 hydropower

Control of Strain Hardening Behavior in High-Mn Austenitic Steels

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Acta Metallurgica Sinica(English Letters) 2014年第3期27卷 546-556页

作者： Wenwen Song tobias Ingendahl Wolfgang Bleck Steel Institute RWTH Aachen University Intzestr.1 52072 AachenGermany

Austenitic high-Mn steels with Mn contents between approximately 15 and 30 wt% gain much interest because of their excellent mechanical properties and the option for adjusting strain hardening behavior due to different deformation mechanisms. 2D and 3D composition-dependent stacking fault energy （SFE） maps indicate the effect of chemical composition and temperature on SFE and consequently on the deformation mechanisms. Three steels with different chemical compositions and the same or different SFE are characterized in quasi-static tensile tests. The control parameters of strain hardening behavior in the high-Mn austenitic steels are described, and consequences for future developments are discussed.

关键词： High-Mn austenitic steels Stacking fault energy Strain hardening

A Mechanical Model for the Adhesion of Spiders to Nominally Flat Surfaces

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Journal of Bionic Engineering 2009年第2期6卷 135-142页

作者： Alessandro Gasparetto tobias Seidl Renato Vidoni DIEGM Department of ElectricalManagement and Mechanical EngineeringUniversity of Udine Advanced Concepts Team European Space Agency

In dry attachment systems of spiders and geckos, van der Waals forces mediate attraction between substrate and animal tarsus. In particular, the scopula of Evarcha arcuata spiders allows for reversible attachment and easy detachment to a broad range of surfaces. Hence, reproducing the scopula's roughness compatibility while maintaining anti-bunching features and dirt particle repellence behavior is a central task for a biomimetic transfer to an engineered model. In the present work we model the scopula of E. arcuata from a mechano-elastic point of view analyzing the influence of its hierarchical structure on the attachment behavior. By considering biological data of the gecko and spider, and the simulation results, the adhesive capabilities of the two animals are compared and important confirmations and new directives in order to reproduce the overall structure are found. Moreover, a possible suggestion of how the spider detaches in an easy and fast manner is proposed and supported by the results.

关键词： bionics spider dry adhesion mechano-elastic model hierarchical structure

The equilibrium stability for a smooth and discontinuous oscillator with dry friction

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Acta Mechanica Sinica 2016年第2期32卷 309-319页

作者： Zhi-Xin Li Qing-Jie Cao Alain Léger School of Astronautics Centre for Nonlinear Dynamics Research Harbin Institute of Technology Harbin 150001 China Laboratoire de Mecanique et d' Acoustique CNRS 31 Chemin Joseph Aiguier 13402 Marseille Cedex 20 France

In this paper,we investigate the equilibrium stability of a Filippov-type system having multiple stick regions based upon a smooth and discontinuous（SD） oscillator with dry *** sets of equilibrium states of the system are analyzed together with Coulomb friction conditions in both（ f_n,f_s） and（x,˙x） *** the stability analysis,Lyapunov functions are constructed to derive the instability for the equilibrium set of the hyperbolic type and La Salle＇s invariance principle is employed to obtain the stability of the nonhyperbolic *** demonstrates the existence of a thick stable manifold and the interior stability of the hyperbolic equilibrium set due to the attractive sliding mode of the Filippov property,and also shows that the unstable manifolds of the hyperbolic-type are that of the endpoints with their saddle *** calculations show a good agreement with the theoretical analysis and an excellent efficien y of the approach for equilibrium states in this particular Filippov ***,the equilibrium bifurcations are presented to demonstrate the transition between the smooth and the discontinuous regimes.

关键词： SD oscillator Equilibrium set Dry friction Coulomb’s cone