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81.
Asphaltene filled LDPE composite were prepared and characterized. The composites were studied to determine the reinforcement imparted by the asphaltene on the durability of LDPE polymer. The study showed that the composites have higher melting and crystalline behavior, delays the degradation induced by heat and acts as a thermal barrier limiting the emission of the gaseous degradation products, resulting in an increase in the thermal stability of the composites, higher tensile strength, have higher values of the storage and loss modulus. 5 wt% of asphaltenes added in the LDPE afforded the best dispersion in the polymeric matrix, larger crystallite size, enhanced thermal stability, highest relative degree of crystallinity and improved mechanical tensile or thermo-mechanical properties.  相似文献   
82.
The path toward realizing next-generation petascale and exascale computing is increasingly dependent on building supercomputers with unprecedented numbers of processors. To prevent the interconnect from dominating the overall cost of these ultrascale systems, there is a critical need for scalable interconnects that capture the communication requirements of ultrascale applications. It is, therefore, essential to understand high-end application communication characteristics across a broad spectrum of computational methods, and utilize that insight to tailor interconnect designs to the specific requirements of the underlying codes. This work makes several unique contributions toward attaining that goal. First, we conduct one of the broadest studies to date of high-end application communication requirements, whose computational methods include: finite difference, lattice Boltzmann, particle-in-cell, sparse linear algebra, particle-mesh ewald, and FFT-based solvers. Using derived communication characteristics, we next present the fit-tree approach for designing network infrastructure that is tailored to application requirements. The fit-tree minimizes the component count of an interconnect without impacting application performance compared to a fully connected network. Finally, we propose a methodology for reconfigurable networks to implement fit-tree solutions. Our Hybrid Flexibly Assignable Switch Topology (HFAST) infrastructure, uses both passive (circuit) and active (packet) commodity switch components to dynamically reconfigure interconnects to suit the topological requirements of scientific applications. Overall, our exploration points to several promising directions for practically addressing the interconnect requirements of future ultrascale systems.  相似文献   
83.
84.
The solubilization and physicochemical behavior of a coordination complex of nickel, namely [Ni(im)6]F2·5H2O [hexakis(imidazole)nickel(II) fluoride pentahydrate], in aqueous micellar media of anionic surfactants, i.e., sodium dodecyl sulfate (SDS) and sodium stearate (SS), were investigated by using UV–Vis spectroscopy and electrical conductivity measurements. Spectroscopic techniques were used for the computation of binding constant (Kb), partition coefficient (Kx), change in free energy of binding (ΔGb), and change in free energy of partition (ΔGp), whereas electrical conductivity data was helpful to calculate thermodynamic parameters of micellization of surfactants in the presence of the Ni complex, i.e., standard entropy of micellization (ΔSm), free energy (ΔGm), and enthalpy of micellization (ΔHm). It is evident from the results that solubilization of the Ni complex takes place because of electrostatic as well as hydrophobic interactions. The presence of the Ni complex in micellar media increases the critical micelle concentration of both surfactants owing to the structure‐breaking effect.  相似文献   
85.
The incorporation of nanoparticles (NPs) into a casting solution is a widely used practice for controlling the membrane fouling tendency, but the specific role of NPs in fouling control from an internal porous structure optimization has seldom been investigated. In this study, we evaluated the specific role of titanium dioxide (TiO2)–NPs (Degussa P25) in mitigating membrane organic fouling. We prepared the membranes by tailoring the concentrations of the NPs well; this resulted in an optimized membrane microstructure consisting of fingerlike voids (beneath the skin layer of the membrane) and spongy voids (adjacent to the fingerlike voids). The NP incorporation induced the formation of spongy voids beneath the skin layer, and the increase in the NP concentration increased the formation of spongy voids. Moreover, surface images obtained by scanning electron microscopy, X‐ray photoelectron spectroscopy results, and contact angles confirmed that TiO2–NPs were almost absent on the skin layer. Antifouling experiments were performed with a model organic foulant in two flow orientations [fingerlike voids facing the retentate (FVR) and spongy voids facing the retentate (SVR)]. The results show that the membrane fluxes in FVR decreased more than those in SVR. The membrane with 1.5 wt % TiO2 operated in SVR exhibited the lowest flux decline; this suggested that spongy voids with TiO2 exposure could mitigate fouling to a greater extent. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43265.  相似文献   
86.
Multiphase Reactors Engineering and Applications Laboratory (mReal) has designed and constructed a scaled‐down dual‐channel facility to investigate plenum‐to‐plenum natural circulation heat transfer through two channels for coolant flow that would be encountered during a loss of flow accident in the prismatic modular reactor (PMR). Heat transfer characterization of the current facility has been investigated under different upper plenum and cooled channel outer surface temperatures using sophisticated flush mounted heat transfer sensors. Results show a reduction in the values of local heat‐transfer coefficient and Nusselt number along the heated channel with increasing outer surface temperatures. One significant observation was the heat transfer reversal close to heated channel exit, where the heat flows from gas to the channel wall. This flow reversal is attributed to recirculation at the heated channel exit to the upper plenum. The average heat transfer results, when compared with previous literature, showed a similar qualitative trend. © 2016 American Institute of Chemical Engineers AIChE J, 63: 387–396, 2017  相似文献   
87.
88.
This work presents a hardware implementation of an FIR filter that is self-adaptive; that responds to arbitrary frequency response landscapes; that has built-in coefficient error tolerance capabilities; and that has a minimal adaptation latency. This hardware design is based on a heuristic genetic algorithm. Experimental results show that the proposed design is more efficient than non-evolutionary designs even for arbitrary response filters. As a byproduct, the paper also presents a novel flow for the complete hardware design of what is termed as an Evolutionary System on Chip (ESoC). With the inclusion of an evolutionary process, the ESoC is a new paradigm in modern System on Chip (SoC) designs. The ESoC methodology could be a very useful structured FPGA/ASIC implementation alternative in many practical applications of FIR filters.  相似文献   
89.
We consider stabilisation for a linear ordinary differential equation system with input dynamics governed by a heat equation, subject to boundary control matched disturbance. The active disturbance rejection control approach is applied to estimate, in real time, the disturbance with both constant high gain and time-varying high gain. The disturbance is cancelled in the feedback loop. The closed-loop systems with constant high gain and time-varying high gain are shown, respectively, to be practically stable and asymptotically stable.  相似文献   
90.
The mapping of regulatory guidelines with organizational processes is an important aspect of a regulatory-compliance management system. Automating this mapping process can greatly improve the overall compliance process. Currently, there is research on mapping between different entities such as ontology mapping, sentence similarity, semantic similarity and regulation-requirement mapping. However, there has not been adequate research on the automation of the mapping process between regulatory guidelines and organizational processes. In this paper, we explain how Natural Language Processing and Semantic Web technologies can be applied in this area. In particular, we explain how we can take advantage of the structures of regulation-ontology and the process-ontology in order to compute the similarity between a regulatory guideline and a process. Our methodology is validated using a case study in the Pharmaceutical industry, which has shown promising results.  相似文献   
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