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排序方式: 共有2392条查询结果,搜索用时 15 毫秒
91.
Sanghee Lee Theresa R. Mendoza Danielle N. Burner Michelle T. Muldong Christina C. N. Wu Catalina Arreola-Villanueva Abril Zuniga Olga Greenburg William Y. Zhu Jamillah Murtadha Evodie Koutouan Naomi Pineda Hao Pham Sung-Gu Kang Hyun Tae Kim Gabriel Pineda Kathleen M. Lennon Nicholas A. Cacalano Catriona H. M. Jamieson Christopher J. Kane Anna A. Kulidjian Terry Gaasterland Christina A. M. Jamieson 《International journal of molecular sciences》2022,23(6)
92.
Dan Lupu Ovidiu ArdeleanGabriela Blanita Gheorghe BorodiMihaela D. Lazar Alexandru R. BirisColdea Ioan Maria MihetIoan Misan Gabriel Popeneciu 《International Journal of Hydrogen Energy》2011,36(5):3586-3592
A new metal-organic framework [Fe3O(OOC-C6H4-COO)3(H2O)3]Cl·(H2O)x was synthesized with a specific surface area of 2823 m2/g and a lattice parameter of 88.61 Å. Isostructural with MIL-101, this compound exhibits similar hydrogen adsorption properties, with maximum adsorption capacity of 5.1wt.% H at 77 K. The adsorption enthalpy of hydrogen for MIL-101 and ITIM-1 (MIL-101Fe) at zero coverage was calculated for a wide temperature range of 77 K ÷ 324 K, considering corrections for the variation of hydrogen gas entropy with the temperature. The resulted adsorption enthalpy is 9.4 kJ/mol for MIL-101, in excellent agreement with the value reported in literature from microcalorimetric measurements, and a value of 10.4 kJ/mol at zero coverage was obtained for ITIM-1 (MIL-101Fe). 相似文献
93.
Gabriel Rodrigues de Almeida Neto Cesar Augusto Gonçalves Beatrice Daniel Rodrigo Leiva Luiz Antonio Pessan 《International Journal of Hydrogen Energy》2021,46(46):23767-23778
This study investigates the preparation of polyetherimide (PEI) – LaNi5 composites films for hydrogen storage. Prior to the polymer addition, LaNi5 was ball-milled at different conditions (250, 350, and 450 RPM) and annealed at 500 °C for 1 h under vacuum. The composites were produced with BM-LaNi5-350 (PEI/LaNi5-350) and annealed BM-LaNi5-350 (PEI/LaNi5-350-TT). Membranes were successfully produced through solvent casting assisted by an ultrasonic bath. The particles dispersion and the film morphology did not change after hydrogenation cycles. In the H2 sorption experiments at 43 °C and 20 bar, the films stored H2 without incubation time; both samples reached a capacity of ~0.6 wt%. The H2 sorption kinetics of PEI/LaNi5-350 was comparable to that of BM-LaNi5-350, whereas PEI/LaNi5-350-TT presented significantly slower kinetics. LaNi5 oxidation was hindered by PEI, showing that it can be explored to improve metal hydrides air resistance. The results demonstrated that PEI films filled with LaNi5 are promising materials for hydrogen storage. 相似文献
94.
The main weakness of elastic optical networks (EON), under dynamic traffic conditions, stems from spectrum fragmentation. A lot of research efforts have been dedicated during recent years to spectrum defragmentation. In this work, a thorough study about proactive defragmentation is carried out. Effects of the different defragmentation parameters on the EON performance are analyzed, and appropriate values of the defragmentation period, which guarantee suitable network performance while keeping the network control complexity at reasonable values, are obtained by means of extensive simulations. Benefit obtained by applying different defragmentation strategies, in terms of increase in the supported load at a given bandwidth blocking probability, is also reported. Different traffic conditions and network topologies are simulated to assess the validity of the obtained results. 相似文献
95.
Traditional fault-tolerance techniques relying on spatial and temporal redundancy typically imply high power, delay, and area overheads. Cost-effective solutions often depend on system’s design and hardware platform at hand. Particularly for Field-Programmable Gate Arrays (FPGAs), soft errors on the configuration memory are a significant dependability threat. In this work, we present an extended and comprehensive fault tolerance mechanism especially suited for dealing with configuration faults on FPGA-based systems that must deal multiple failure modes. Each failure mode may present different criticality and probability of occurrence, and these properties are measured and exploited to provide low-cost solutions when compared to standard approaches such as triple modular redundancy. The exploited properties are typically found in critical monitoring systems that may trigger security- or safety-critical alarms and warnings in general. In such systems, failing to trigger an alarm when necessary is frequently regarded as more critical than providing an occasional false alarm. For instance, Regular Expression Matching (REM), a compute-intensive mechanism heavily used to perform Deep Packet Inspection in critical network applications, presents such properties, and it can be greatly accelerated by FPGAs to meet performance constraints in high-throughput networks. Therefore, we use FPGA-based REM engines as a case study to demonstrate the effectiveness of the proposed techniques. Additionally, a mutually-aware placement and scrubbing mechanism is introduced to reduce the repair time, improving the system reliability and availability. Experimental results show that the failure rate and the repair time can be reduced by 95 and 90% respectively while avoiding the costs of triplication. 相似文献
96.
97.
Gabriel Bustamante Patrick Danès Thomas Forgue Ariel Podlubne Jérôme Manhès 《Autonomous Robots》2018,42(2):477-490
In static scenarios, binaural sound localization is fundamentally limited by front-back ambiguity and distance non-observability. Over the past few years, “active” schemes have been shown to overcome these shortcomings, by combining spatial binaural cues with the motor commands of the sensor. In this context, given a Gaussian prior on the relative position to a source, this paper determines an admissible motion of a binaural head which leads, on average, to the one-step-ahead most informative audio-motor localization. To this aim, a constrained optimization problem is set up, which consists in maximizing the entropy of the next predicted measurement probability density function over a cylindric admissible set. The method is appraised through geometrical arguments, and validated in simulations and on real-life robotic experiments. 相似文献
98.
Roberta K. Rodrigues Lucas A. S. Silva Gabriel G. Vargas Bruno V. Loureiro 《Journal of surfactants and detergents》2020,23(1):21-40
This study describes the effects of wormlike micelles formed by the commercial surfactants tallowalkylamidopropyl dimethylamine oxide (Aromox APA-TW) and oleyl methyl bis(2-hydroxyethyl) ammonium chloride (Ethoquad O/12) as drag reducers. Ethoquad O/12 is immune to degradation by heat and microorganisms. Conversely, Aromox APA-TW is biodegradable in the environment, and its susceptibility to heat-induced degradation was previously assessed. This work considers the effects of temperature, salt, and time on the drag-reduction capacity (in different Reynolds number) of wormlike micelles of these two surfactants. Wormlike micelles formed by Aromox APA-TW are able to reduce drag at higher temperatures compared to wormlike micelles formed by Ethoquad O/12. However, Aromox APA-TW can degrade after being heated to 80 °C and also after storage of the wormlike micelle solutions. Ethoquad O/12 does not undergo degradation after being heated or stored. These surfactants have the potential to be used as additives in industrial operations, as the wormlike micelles formed are able to reduce drag in systems with long pumping distances or recirculation, even in solutions with high salt concentrations (brine) and high temperatures. 相似文献
99.
100.
Samia Tássia Andrade Maciel Alexander Andrey Lopes da Silva Yasmin Guimarães Pedro Cristiano Nunes da Silva Leôncio Diógenes Tavares Câmara João Monnerat Araújo Ribeiro de Almeida Emerson Schwingel Ribeiro Gabriel Francisco da Silva Lisiane Santos Freitas Donato Alexandre Gomes Aranda 《化学工程与技术》2020,43(11):2149-2159
The catalytic hydrolysis of soybean oil was used as an alternative for the production of monoglycerides (MG) and diglycerides (DG). The reactions were conducted in a stainless-steel tubular reactor in the temperature range of 240–290 °C, on niobium phosphate (NBP) and niobium oxide (NBO) as catalysts. In the hydrolysis reactions at 270 °C, the maximum selectivities of the products of interest were obtained at 22 % MG and 48 % DG for the reaction with NBP, and 7 % MG and 33 % DG with NBO, for 59 % and 36 % of triglyceride conversion in 10 min, respectively. The proposed kinetic model presented a good fit of the theoretical model with the experimental data, showing that the previous hypotheses considered for the mechanism development are suitable for describing the kinetics of soybean oil hydrolysis. 相似文献