Modern urban planning not only has to coordinate the needs of many different inhabitants and traffic participants, but also faces other challenges such as modal shift towards sustainable transportation. A comprehensiv...
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Modern urban planning not only has to coordinate the needs of many different inhabitants and traffic participants, but also faces other challenges such as modal shift towards sustainable transportation. A comprehensive database of historical traffic, which would facilitate a decision based on data, is lacking in many cities. This became clear in consultation with our partners from the city of Krefeld. A novel method is the use of public available traffic information such as traffic colors or travel time data from navigation providers. In this contribution a method is applied to estimate the travel duration from the traffic colors on city level. Here we show for the first time how it can be applied cost-effectively and how the accuracy can be estimated in combination with a validation of the database by test drives for urban streets. It will also be investigated, whether speed variation has an influence on the estimation of driving time. We found out that this influence is negligible for the investigated example and the mean deviation of estimation accuracy from the measured values is less than six percent. Based on these promising results, it is possible to build up a database for improved urban and traffic planning at low cost. This can lead to better information for all traffic participants, thus, an improved traffic flow control could result in a reduction of car traffic emissions in the end.
The study investigated the synergistic effects of green tea extract (GTE) and black rice extract (BRE) on total phenolic content, flavonoid content, antioxidant activities and angiotensin-converting enzyme (ACE) inhib...
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Polyvinyl chloride (PVC) has many applications in construction, such as pipes, floors, roofs, walls, frames, and cables. Since it is easily degraded by heat, a heat stabilizer must be added to the PVC resin before it ...
Polyvinyl chloride (PVC) has many applications in construction, such as pipes, floors, roofs, walls, frames, and cables. Since it is easily degraded by heat, a heat stabilizer must be added to the PVC resin before it is molded into final products. Mixed calcium/zinc carboxylate has become a popular PVC thermal stabilizer since it is more friendly than the conventional lead base thermal stabilizers and is relatively inexpensive. This research aims to investigate the synthesis and assess the effectiveness of a mixed calcium/zinc thermal stabilizer in stabilizing PVC. The stabilizer was prepared from palm fatty acid distillate (PFAD), and different metal salt-to-fatty acid molar ratios were employed for the study. The synthesis was carried out by a metathesis method at 10% deficiency, stoichiometric, and 10% excess of metal salt-to-fatty acid molar ratio. The stabilizing effects of the obtained metal carboxylates as mixed metal thermal stabilizers have also been evaluated by standard thermal stability tests. The calcium and zinc carboxylates prepared at a 10% deficiency were found to have high pHs and lower metal contents than those at stoichiometric molar ratios due to the presence of residual sodium soap. Their thermal stabilizing effects on PVC are also worst when prepared at a deficient metal salt-to-fatty acid molar ratio. Increasing the metal-to-fatty acid molar ratio above the stoichiometric requirement lowers the thermal stabilizing effect of zinc carboxylate but has little influence on the thermal stabilizing effect of calcium carboxylate obtained. Synthesis at stoichiometric metal salt-to-fatty acid molar ratios is recommended for preparing calcium and zinc carboxylates as mixed metal PVC thermal stabilizers.
Convective heat transfer coefficients for palm fatty acid distillate have been measured in a batch stirred tank. The heat transfer took place at a dynamic stage in jacketed tanks with a working volume of 3.5 and 10.0 ...
Convective heat transfer coefficients for palm fatty acid distillate have been measured in a batch stirred tank. The heat transfer took place at a dynamic stage in jacketed tanks with a working volume of 3.5 and 10.0 liters, at temperature ranging from 60 to 80°C and Reynolds number ranging from 1000 to 6000. The results indicate that the convective heat transfer coefficient is in the range of 230 to 680 W·m-2·°C-1. The data fit well with the existing empirical model and can be expressed as Nu=0.5·Re⅔·Pr⅓ where Nu, Re, and Pr are Nusselt, Reynolds, and Prandtl numbers.
In competitive segments like automobile and bus manufacturing industries, quality of vehicles need to be improved constantly to meet internal and external market demands. Compliance with international standard regulat...
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Anode design is a crucial factor for the further development of lithium-ion battery (LIB) technology, especially in terms of achieving high charging rate performance, as typically needed in electric vehicles (EV). In ...
Anode design is a crucial factor for the further development of lithium-ion battery (LIB) technology, especially in terms of achieving high charging rate performance, as typically needed in electric vehicles (EV). In the present work, a unique battery test cell was designed and fabricated to study in-situ the mechanical behavior of the silicon nanowire electrode during electrochemical lithiation using synchrotron X-ray microdiffraction. Modelling of the nanostructured anode was also performed to provide further understanding of the in-situ findings. The combined approach provides further in-depth understanding of the evolution of the mechanics in the silicon nanowires (1D nanostructure) during operation of the battery, and furthermore shows the path for potentially enhancing the performance of the device. 3D nanostructures have been identified as the key to dramatically enhanced kinetics performance of LIB. However, existing fabrication methodologies for 3D nanostructures are inherently expensive – using advanced lithography techniques or other nanopatterning methodologies, as well as using additive manufacturing approaches. Electrospinning (as an integrated additive manufacturing methodology) may be used to produce low-cost 3D-printed fiber structures. This will pave the way to achieve the order of magnitude increase in battery kinetics as needed to realize the vision of the sustainable transportation.
Nanoindentation is widely used to investigate mechanical properties of materials at small scales. In this work, owing to the presence of contrasting interfaces along rolling (RD) and transverse direction (TD), a 16 nm...
Nanoindentation is widely used to investigate mechanical properties of materials at small scales. In this work, owing to the presence of contrasting interfaces along rolling (RD) and transverse direction (TD), a 16 nm accumulative roll bonding (ARB) Cu/Nb nanolaminate as a test material due to its crystallographic anisotropy was used. Nanoindentation was performed and then Scanning Probe Microscopy (SPM) data was conducted to measure the pile-up height along RD and TD in the nanoscale Cu/Nb multilayered materials. It was found that the 16 nm Cu/Nb ARB nanolayered material along RD showed higher surface pile-up than TD attributed the observation to the variation in the Cu/Nb interface plasticity along RD and TD. Further, a comparation and validation of experimental indentation data by performing 2D axisymmetric Finite Element Analysis (FEA) indicated that the simulation compares well with the experimentally generated load-displacement curves, while qualitative agreement was obtained with the pileup data. It is believed that the characterization of surface pile-up is very important for enabling the nanoscale Cu/Nb ARB nanolaminates as the novel stretchable/flexible metallic conductor materials (with emerging applications such as e-skins, human-computer interaction, and soft robotics) that may prove crucial for the global green and sustainability efforts (soft robots for collecting plastic trashes in ocean).
With a glulam-based post-beam building system, a variety of building solutions is offered on the market for multi-story buildings. The building system must be adaptable to the demands of each project. However, short l...
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Calophyllum brasiliense Cambess (guanandi) is a native species with significant economic potential for reforestation and the wood industry, as well as a promising source of pharmaceutical bioinputs, aligning with the ...
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Calophyllum brasiliense Cambess (guanandi) is a native species with significant economic potential for reforestation and the wood industry, as well as a promising source of pharmaceutical bioinputs, aligning with the United Nations' 2030 Agenda for Sustainable development. This study evaluated the feasibility of utilizing the vegetable oil obtained from guanandi seeds (OVSG) as a pharmaceutical ingredient. Gas chromatography-mass spectrometry analysis identified palmitic, oleic, linoleic, and stearic acids in the OVSG, which together represent 95 % of the lipid fraction of the bioinput. Biological in vitro assays using L929 fibroblasts demonstrated non-cytotoxicity (CI 50 > 200 µg/mL), stimulation of cell proliferation, and healing activity at low concentrations (12.5 - 25 µg/mL). The anionic base cream, prepared by the conventional method and containing 10 % w/w of OVSG, in the absence of synthetic emollients, showed adequate preliminary physical stability and the required texture profile for topical use. The wound healing activity of this formulation was compared with that of a cream with the same formulation, but without OVSG and containing 5 % w/w of allantoin, demonstrating an equivalent effect. This study is unprecedented and demonstrates that OVSG is a viable bioinput for applications as an emollient, positioning the species as a sustainable source of non-wood forest resources for pharmaceutical applications.
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