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281.
Application of the CFD methodology for risk assessment of hydrogen applications and associated support of regulation, codes and standards has been growing its momentum during the last years. The CFD tools applied should prove to be “adequately” validated for hydrogen applications. This contribution focuses on the hydrogen related validation work performed with the CFD code ADREA-HF. The code is a three dimensional transient fully compressible flow and dispersion CFD solver, able to treat highly complex geometries using the porosity formulation on Cartesian grids. The ADREA-HF validation effort was performed within various EC co-funded projects (EIHP, EIHP-2, HyApproval, HyPer, HySafe). Various types of hydrogen release scenarios were considered, including gaseous and liquefied releases, open, semi-confined and confined environments, sonic (under-expanded) and low momentum releases. In parallel to its validation the ADREA-HF code has been extensively used for regulations, codes and standards support.  相似文献   
282.
This article studies the mechanical properties of short fiber reinforced polymer blends comprised of a soft thermoplastic matrix (polyethylene, PE), a rigid dispersed thermoplastic phase (polyamide-6, PA6) and glass fiber reinforcement. These ternary composites are designed as a model system to investigate the impact of the mutual interactions of the three phases on the composite mechanical properties. For this purpose two types of fibers are used, dispersed-phase and matrix-phase compatible fibers, respectively.  相似文献   
283.
This paper reports our progress in developing an advanced video-on-demand (VoD) testbed, which will be used to accommodate various multimedia research and applications such as Electronic News on Demand, Columbia's Video Course Network, and Digital Libraries. The testbed supports delivery of MPEG-2 audio/video stored as transport streams over various types of networks, e.g., ATM, Ethernet, and wireless. Both software and hardware video encoders/decoders are used in the testbed. A real-time video pump and a distributed application control protocol (MPEG-2's DSM-CC) have been incorporated. Hardware decoders and set-tops are being used to test wide-area video interoperability. Our VoD testbed also provides an advanced platform for implementing proof-of-concept prototypes of related research. Our current research focus covers video transmission with heterogeneous quality-of-service (QoS) provision, variable bitrate (VBR) traffic modeling, VBR server scheduling, video over Internet, and video transmission over IP-ATM hybrid networks. An important aim is to enhance interoperability. Accommodation of practical multimedia applications and interoperability testing with external VoD systems has also been undertaken.  相似文献   
284.
The cultivation of soilless tomato in greenhouses has increased considerably, but little is known about the assembly of the root microbiome compared to plants grown in soil. To obtain such information, we constructed an assay in which we traced the bacterial and fungal communities by amplicon-based metagenomics during the cultivation chain from nursery to greenhouse. In the greenhouse, the plants were transplanted either into agricultural soil or into coconut fiber bags (soilless). At the phylum level, bacterial and fungal communities were primarily constituted in all microhabitats by Proteobacteria and Ascomycota, respectively. The results showed that the tomato rhizosphere microbiome was shaped by the substrate or soil in which the plants were grown. The microbiome was different particularly in terms of the bacterial communities. In agriculture, enrichment has been observed in putative biological control bacteria of the genera Pseudomonas and Bacillus and in potential phytopathogenic fungi. Overall, the study describes the different shaping of microbial communities in the two cultivation methods.  相似文献   
285.
Annals of Telecommunications - In emergency care, fast and efficient treatment is vital. The availability of Electronic Medical Records (EMR) allows healthcare professionals to access a...  相似文献   
286.
287.
Wireless Personal Communications - The present paper discusses several security requirements coming from assessment of the use cases developed within the context of the original 5G-PPP “5G...  相似文献   
288.
Inhibition of membrane-bound pyrophosphatase (mPPase) with small molecules offer a new approach in the fight against pathogenic protozoan parasites. mPPases are absent in humans, but essential for many protists as they couple pyrophosphate hydrolysis to the active transport of protons or sodium ions across acidocalcisomal membranes. So far, only few nonphosphorus inhibitors have been reported. Here, we explore the chemical space around previous hits using a combination of screening and synthetic medicinal chemistry, identifying compounds with low micromolar inhibitory activities in the Thermotoga maritima mPPase test system. We furthermore provide early structure-activity relationships around a new scaffold having a pyrazolo[1,5-a]pyrimidine core. The most promising pyrazolo[1,5-a]pyrimidine congener was further investigated and found to inhibit Plasmodium falciparum mPPase in membranes as well as the growth of P. falciparum in an ex vivo survival assay.  相似文献   
289.
In situ polymerization by polycondensation was implemented to disperse crystalline nanocellulose (CNC) in poly(ethylene succinate) (PESu). The in situ polymerization technique resulted in good dispersion of the CNC nanoparticles in the PESu matrix. The polymerization kinetics were altered with increasing CNC content, causing a decrease in the polymer molecular weight. The addition of CNC particles having a large aspect ratio resulted in significant increases in the viscosity of the resulting composites, and significantly enhanced crystallization kinetics. PESu containing well‐dispersed 0.25 wt% CNC maintained the tensile properties of the matrix, demonstrating that at these very low loadings the CNC acts as an efficient nucleating agent, without compromising the mechanical properties and biodegradability POLYM. ENG. SCI., 59:989–995, 2019. © 2019 Society of Plastics Engineers  相似文献   
290.
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