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排序方式: 共有1009条查询结果,搜索用时 31 毫秒
1.
Beierlein Dennis Häussermann Dorothea Traa Yvonne Klemm Elias 《Catalysis Letters》2022,152(10):2908-2919
Catalysis Letters - We developed a rapid aging method for Ni/Al2O3 methanation catalysts mimicking the real aging in the actual application. The method is based on hydrothermal deactivation of the... 相似文献
2.
Alexandros Papadopoulos Issaak Parcharidis Panagiotis Elias Pierre Briole 《International journal of remote sensing》2019,40(16):6365-6382
We analysed the ground deformation across two blocks defined by the Rio-Patras fault from 1993 to 2017 using multi-temporal Synthetic Aperture Radar Interferometry (InSAR) techniques. Our main objective was to contribute to the assessment of seismic hazard near the large city of Patras. Multiple data-sets were used, each one covering different temporal periods. Descending and ascending acquisitions, providing different viewing geometries contribute to fully determine the ground displacement in 3D. The data-sets used are from the European Space Agency’s (ESA) European Remote Sensing (ERS), Environmental Satellite (ENVISAT) and SENTINEL-1 as well as German Aerospace Center (DLR) ’s TERRASAR-X missions. Considering ESA’s missions covering both acquisition geometries and long periods, the southern block, showing lack of a sufficient number of scatterers does not allow the displacement characterization. In contrary, the northern block is characterized by a high number of scatterers having values of maximum likehood ranging from ?3.5 to ?4.3 mm year?1 for ascending geometry and from ?1.6 to ?2.7 mm year?1 for the descending one. The fact that both geometries show negative values of displacements are consistent with downlift movement and at the same time the quantitative differentiation probably indicates an horizontal component as well. 相似文献
3.
Investigations on the Corrosion Properties of Sn–1Cu–1Ni–xAg Lead Free Solders in 3.5% NaCl Solution
Protection of Metals and Physical Chemistry of Surfaces - Due to the directions and environmental legislations from RoHS (Restrictions of Hazardous Substances), WEEE (World Electrical and... 相似文献
4.
Elias Martinez Hernandez Kok Siew Ng 《Clean Technologies and Environmental Policy》2018,20(7):1501-1514
Unlocking the potential and value of lignocellulosic residues is an important step in making biorefineries economically and environmentally promising. This calls for a holistic and systematic approach in designing sustainable industrial systems. In this work, biorefinery systems via biochemical route (acetone–butanol–ethanol or ABE system) and thermochemical route (gasification and mixed alcohols or GMA system) for converting corn stover into biofuels have been designed using a Sustainable Engineering Framework. The framework involves eight main steps: (1) design problem definition, (2) data collection, (3) process synthesis and simulation, (4) process integration, (5) resource recovery from residues, (6) utility system design, (7) economic and environmental modelling and (8) economic value and environmental impact margin analysis for decision making. Consideration of resource recovery from biorefinery waste streams has proven to be the key in making biorefineries self-sustaining and with low environmental impacts. Simultaneous economic and environmental feasibility assessment at the early stage of process design is highly envisaged. The cost of biofuel production in the ABE system has been found to be 49.2 US$/GJ and 69.9 US$/GJ in the GMA system. The greenhouse gas emissions are 46.2 g CO2-eq/GJ for ABE and 19.0 g CO2-eq/GJ for GMA, lower than gasoline (85 g CO2-eq/GJ). The GMA system is not economically compelling though with high environmental benefit, while the ABE system has shown to be both economically and environmentally feasible. 相似文献
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7.
Elias Salameh 《The International journal of environmental studies》2013,70(4):291-300
Two main problems seem to face the use of surface water for domestic purposes in semi‐arid regions. These problems are eutrophication of surface water bodies and the formation of chlorinated hydrocarbons during water treatment. Both problems develop as direct of indirect results of anthropogenic activities. The eutrophication problem will be discussed with reference to King Talal Reservoir, whereas the formation of chlorinated hydrocarbons will be illustrated when discussing the use of the East Ghor Canal water for domestic purposes. 相似文献
8.
Elias C. Aifantis 《Acta Mechanica》2014,225(4-5):999-1012
This is a modest contribution dedicated to the work and virtue of George Weng, a prominent figure in material mechanics and a dear intellectual friend. The paper starts with the basics of gradient theory as applied to elasticity, plasticity and dislocation dynamics by introducing weak non-locality in the constitutive equations through Laplacian terms and corresponding deterministic internal lengths (ILs) characterizing the dominant deformation mechanisms. It then considers the interaction of such deterministic ILs with surface effects associated with internal or external surfaces, as well as stochastic effects associated with pre-existing or deformation-induced random microstructures. Experimentally observed stress drops and strain bursts are interpreted through combined gradient-stochastic models. Statistical features of corresponding deformation processes that cannot be fitted with Boltzmann–Gibbs–Shannon entropy statistics are interpreted by Tsallis q-entropy statistics. Some benchmark novel experiments for the direct determination of ILs for plasticity (by testing bulk specimens with gradient grain size) and dislocation dynamics (by testing thin films in TEM with gradient dislocation density) are proposed. 相似文献
9.
Lina R. Nih Elias Sideris S. Thomas Carmichael Tatiana Segura 《Advanced materials (Deerfield Beach, Fla.)》2017,29(32)
With the number of deaths due to stroke decreasing, more individuals are forced to live with crippling disability resulting from the stroke. To date, no therapeutics exist after the first 4.5 h after the stroke onset, aside from rest and physical therapy. Following stroke, a large influx of astrocytes and microglia releasing proinflammatory cytokines leads to dramatic inflammation and glial scar formation, affecting brain tissue's ability to repair itself. Pathological conditions, such as a stroke, trigger neural progenitor cells (NPCs) proliferation and migration toward the damaged site. However, these progenitors are often found far from the cavity or the peri‐infarct tissue. Poststroke tissue remodeling results in a compartmentalized cavity that can directly accept a therapeutic material injection. Here, this paper shows that the injection of a porous hyaluronic acid hydrogel into the stroke cavity significantly reduces the inflammatory response following stroke while increasing peri‐infarct vascularization compared to nonporous hydrogel controls and stroke only controls. In addition, it is shown that the injection of this material impacts NPCs proliferation and migration at the subventricular zone niche and results, for the first time, in NPC migration into the stroke site. 相似文献