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Evaluation of Screw Reinforcement on Bearing Performance of Wood Depending on Screw Position

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Open Journal of Civil Engineering 2012年第3期2卷 160-166页

作者： Satoru Murakami Akihisa Kitamori Kiho Jung ivon B. hassel Kohei Komatsu RISH Kyoto University Kyoto Japan

In this study, the reinforcement of wood by screws for partial compression perpendicular to the grain was studied. For the estimation of stiffness and strength, the reinforcement effect of screws depending on their position under the loading plate was evaluated by taking into account the internal displacement distribution of the wood. The finite element analysis (FEA) was used to investigate the internal displacement distribution of the wood. Then an approximate function that can be applied to various internal displacement distributions under loading plate was proposed. From the shear resistance mechanism between the screw and wood by taking their relative displacement distribution into consideration, the equations to estimate the initial stiffness and yield strength of the bearing performance of the wood reinforced by screws were derived. Then partial compression test was carried out for wood reinforced by screws with setting screw thread at various positions. The values obtained by the equations corresponded with the tendency of the experimental results. It was found that the screw reinforcement is more effective when its thread is positioned as much as distant from the contact surface.

关键词： Screw Reinforcement FEM Partial Compression Bearing

Adding Hydrated Lime in a Material Made of Clayey Soil and Fibres: Formulation and Effects on Thermo-Mechanical Properties

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Journal of Minerals and Materials Characterization and Engineering 2020年第3期8卷 149-161页

作者： Fati Zoma Fabien H. Yonli Etienne Malbila David Y. K. Toguyeni ivon B. hassel Laboratory of Physics and Chemistry of Environment University Joseph KI-ZERBO Ouagadougou Burkina Faso Laboratory of Thermal and Renewable Energies University Joseph KI-ZERBO Ouagadougou Burkina Faso Department of Engineering Sciences Division of Applied Mechanics Uppsala University Uppsala Sweden

In this study, we have focused our investigations on effect of adding hydrated lime on a locally made composite material, based on clayey earth (soil) and Hibiscus sabdariffa fibres, for envelope (walls) in the building. Prior to sample’s formulation, we selected an appropriate mineral (soil) material based on criteria as: plasticizer power for good workability, dense coarse particles to withstand loads and finally porous structure to take advantage of air insulating character. We then formulated, following a mixing process by shearing and compaction by vibration that we recommend, two composite materials (A), (B) which contain respectively 1% Fibres plus 1% lime, 1% Fibres plus 3% lime. We determined thermal properties by the mean of KD2 Pro thermal analyzer, compression strength accordingly to the standard NF P 18-406, porosity following volumetric and gravimetric methods and pH of soil-hydrated lime solution. As results, up to 5% of hydrated lime, the measured pH is inferior to 12: mineralization of vegetal fibres is highly unlikely. Moreover, we observe that the addition of hydrated lime resulted in a reduction in the number of cracks and their depths;Samples (A) and (B) have a rather compact appearance than the case 1% Fibres without lime (material (C)). Furthermore, with lime stabilization, the insulating potential is improved while the thermal inertia has been deteriorated compared to material (C). However, compressive strength decreases with lime, which could be due to the presence of fibres that would inhibit the hardening of the lime. At last, with 3.39% ± 3.07% MPa, 2.27% ± 11.30% MPa for samples (A), (B) respectively, the minimum required by CRATerre-EAG (guide of CDI, 1996) for construction of envelope (walls) of single storey (ground floor) buildings is met.

关键词： Local Material Hydrated Lime Hibiscus sabdariffa Fibre Thermo-Mechanical Properties Porosity

Engineering nanoparticles to overcome immunological barriers for enhanced drug delivery

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再生工程(英文) 2020年第1期1卷 35-50页

作者： Thomas Malachowski Austin hassel Department of Biomedical Engineering Stony Brook UniversityUnited States

Nanotechnology has recently gained traction in the medical field as a method of targeted delivery and timed release of therapeutic *** interest in this field grows,design considerations of the selected nanotechnology and extensive knowledge of the human immune system are necessary to design an effective system for drug *** and control of an immune response has become an achievable outcome to ensure efficient treatment of target tissues through careful selection of materials and immune *** review outlines the immune system,the challenges created by its inherent functions,biocompatible materials that are presently being used to construct nanoparticles,and molecules and techniques used to manipulate the immune response to nanoparticles.

关键词： Immunomanipulation Inflammation Nanoparticle cloaking Biodegradable materials Immune responses

The Great Realignment： The Politics of Liberalization in Germany

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浙江大学学报（人文社会科学版） 2012年第3期42卷 97-110页

作者： Anke hassel Public Policy H ertie School of Governance 10117 Berlin Germany

Southeast Asian primate communities:the effects of ecology and Pleistocene refuges on species richness

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Integrative Zoology 2013年第4期8卷 417-426页

作者： Heather hassel-FINNEGAN Carola BORRIES Qing ZHAO Phaivanh PHIAPALATH Andreas KOENIG Department of Anthropology Stony Brook UniversityStony BrookNYUSA Biology Department Swarthmore CollegeSwarthmorePAUSA College of Life Science Peking UniversityBeijingChina International Union for Conservation of Nature VientianeLao PDR

We examined historical and ecological factors affecting current primate biodiversity in Southeast *** Africa,Madagascar and South America,but not Southeast Asia,primate species richness is positively associated with average rainfall and distance from the equator(latitude).We predicted that Southeast Asia’s non-conformance may be due to the effect of dispersed Pleistocene refuges(locations of constricted tropical forests during glacial maxima which today are at least 305 m in altitude).Based on 45 forested sites(13 on large islands;32 on the mainland)of at least 100 km^(2) to minimize recent human impact,we determined correlations between extant primate species richness and rainfall,latitude and supplementary ecological variables,while controlling for refuges and *** found that refuge sites had significantly higher primate species richness than non-refuges(t=-2.76,P<0.05),and distance from the nearest Pleistocene refuge was negatively correlated with species richness for non-refuge sites(r=-0.51,P<0.05).There was no difference in species richness between sites on large islands and the mainland(t=-1.4,P=0.16).The expected positive relationship between rainfall and species richness was not found(r=0.17,P=0.28).As predicted,primate species richness was negatively correlated with latitude(r=-0.39,P<0.05)and positively correlated with mean temperature(r=0.45,P<0.05).General linear models indicated that a site’s latitude(F_(1,38)=6.18,P<0.05)and Pleistocene refuge classification(F_(1,42)=5.96,P<0.05)were the best predictors of species *** ecological and historical factors contribute to present day primate species richness in Southeast Asia,making its biodiversity less of an outlier than previously believed.

关键词： allopatric speciation island latitude mainland rainfall temperature

Mixing Enhancement in a Coaxial Jet Mixer

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Advances in Materials Physics and Chemistry 2012年第4期2卷 134-137页

作者： Valery Zhdanov Egon hassel Rostock University Department of Technical Thermodynamics 18059 Rostock Germany Rostock University Department of Technical Thermodynamics 18059 Rostock Germany

Experimental investigations of mixing in a coaxial jet mixer have been carried out applying Particle Image Velocimetry (PIV) and Planar Laser Induced Fluorescence (PLIF) methods simultaneously. A developed turbulent jet of an aqueous solution of Rhodamine 6G issued from the nozzle was mixed with co-flow water. Velocity and scalar fields were studied quite far downstream flow to control the formation of a quasi homogeneous mixture. The intensity of mixing was varied by mouthpieces with rectangular and triangular vortex generators of different sizes installed in the nozzle. The formation length of the quasi homogeneous mixture was reduced about 10 jet diameters by the tabs. The triangular tabs were more effective than the rectangular ones.

关键词： Mixing Turbulent Flow Vortex Generators PIV PLIF

Asymmetry in Value Relevance of Environmental Performance （EP） Information： Contingency Effects of Size and Industry

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Journal of Modern Accounting and Auditing 2013年第6期9卷 777-789页

作者： Natalia Semenova Lars G. hassel Abo Akademi University Turku Finland Umea University Umea Sweden

Contemporary research documents a positive but weak price premium from environmental performance （EP）. The specific circumstances of pricing EP of large and small companies and in polluting and clean industries have not, however, been investigated. This study predicts that financial markets price EP beyond financial fundamentals differently, depending on company size and the environmental risk of the industry and provides evidence relying on a set of the Sweden Stock Market 300 （SIX 300） companies listed on the Stockholm Stock Exchange （OMX Stockholm）. Applying a value relevance model, the average results are in line with previous findings that EP adds value beyond the book value of equity and earnings. The asymmetry in EP is, however, driven by company size and the environmental risk of the industry. This study suggests that large companies in low-risk industries obtain strong price premiums from being environmental industry leaders. In contrast, small companies and also companies in high-risk industries do not necessarily accrue the same market benefits.

关键词： environmental performance (EP) market premium industry risk size moderated regression analysis (MRA)

Cutting and Welding of High-Strength Steels Using Non-Vacuum Electron Beam as a Universal Tool for Material Processing

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World Journal of Engineering and Technology 2016年第4期4卷 598-607页

作者： Thomas hassel Nils Murray Georgii Klimov Alexander Beniyash Institute of Materials Science Leibniz Universit&auml t Hannover Garbsen Germany

Using a non-vacuum electron beam, a two-step process chain for plate materials is a feasible possibility. Cutting and welding can be performed in subsequent steps on the same machine for a highly productive process chain. The electron beam is a tool with high energy conversion efficiency, which is largely independent of the type of metal. Its high power density qualifies the non-vacuum electron beam as an outstanding energy source for the well-known NVEB welding as well as for high-speed cutting. Welding is possible with or without filler wire or shielding gas, depending on the application. The NVEB-cutting process employs a co-moving cutting head with a sliding seal for extremely high cutting speeds producing high quality edges. Due to direct removal of fumes and dust, NVEBC with local suction is an exceptionally clean and fast process. The NVEB welding process is possible directly after cutting, without further edge preparation. The potential directions of development of non-vacuum electron beam technologies are discussed. An exemplary two-step process chain using high-strength steel is presented to highlight possible application in industries such as general steel construction, automotive, shipbuilding, railway vehicle or crane construction. An analysis of the mechanical properties of the resulting weld seam is presented.

关键词： Welding High-Strength Steels Non-Vacuum Electron Beam Welding Non-Vacuum Electron Beam Cutting

Value of Corporate Responsibility

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Value of Corporate Responsibility