78 results match your criteria: "Research Institute of Energy[Affiliation]"

An extended version of Birnbaum-Saunders distribution with five parameters is introduced. Theoretical aspects of five-parameter Birnbaum-Saunders distribution and the maximum likelihood estimation of parameters are presented. The reliability and applicability of the proposed distribution is evaluated using both simulation and real-world data namely bicoid gene expression profile.

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Hydrogen storage is a key technology for the advancement of hydrogen and fuel cell power technologies in stationary and portable applications. MgH, an example of a high-capacity hydrogen storage material, has two major material challenges for practical applications: slow hydrogen desorption kinetics and high hydrogen desorption temperature. Numerous studies have reported enhancements in kinetics but only a few in thermodynamics.

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Facile Synthesis of LiH-Stabilized Face-Centered-Cubic YH High-Pressure Phase by Ball Milling Process.

Inorg Chem

October 2019

Research Center for Environmentally Friendly Materials Engineering , Muroran Institute of Technology, 27-1, Mizumoto-cho, Muroran , Hokkaido , 050-8585 , Japan.

Article Synopsis
  • A face-centered-cubic (FCC) YH phase is stable only under high pressures but can be stabilized at ambient pressure by replacing some Y with lithium (10 mol % Li), creating a material called LSY.
  • Previous methods to synthesize LSY required high pressure, yielding only small amounts, but a new ball milling (BM) process allows production in grams, which is much more practical for mass production.
  • Although the BM sample has a lower crystallinity compared to the high-pressure sample, it can still reversibly absorb and release hydrogen at specific temperatures, with its structure changing to a hexagonal phase at higher rehydrogenation temperatures due to thermal instability.
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Semiclathrate hydrates are a crystalline host-guest material, which forms with water and ionic substances such as tetra--butylammonium (TBA) salts. Various anions can be used as a counter anion to the TBA cation, and they can modify thermodynamic properties of the semiclathrate hydrates, which are critical for applications, for example, cold energy storage and gas separation. In this study, the semiclathrate hydrates of the TBA glycolate were newly synthesized.

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Experiments were performed to evaluate the kinetic inhibition effect of Type I and Type III antifreeze proteins (AFPs), polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP) on the growth of tetrahydrofuran (THF) clathrate hydrate crystals using the unidirectional growth technique. The crystal growth interface shifted under an applied temperature gradient over a given time. Type I AFP was the most effective kinetic inhibitor, followed by PVP, Type III AFP and PVA.

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Aiming to develop a highly effective and durable catalyst for high-pressure H production from dehydrogenation of formic acid (DFA), the ligand effect on the catalytic activity and stability of Cp*Ir (Cp*:pentamethylcyclopentadienyl anion) complexes were investigated using 5 different kinds of N,N'-bidentate ligands (bipyridine, biimidazoline, pyridyl-imidazoline, pyridyl-pyrazole and picolinamide). The Ir complex with biimidazoline ligand exhibited the highest catalytic activity, but deactivation occurred readily at high pressure. The pyridine moiety in the ligand can enhance the stability of Ir complex catalysts for the high-pressure reaction.

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This paper takes a novel approach for forecasting the risk of disease emergence by combining risk management, signal processing and econometrics to develop a new forecasting approach. We propose quantifying risk using the Value at Risk criterion and then propose a two staged model based on Multivariate Singular Spectrum Analysis and Quantile Regression (MSSA-QR model). The proposed risk measure (PLVaR) and forecasting model (MSSA-QR) is used to forecast the worst cases of waterborne disease outbreaks in 22 European and North American countries based on socio-economic and environmental indicators.

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Lithium adsorptive properties of HTiO adsorbent from shale gas produced water containing organic compounds.

Chemosphere

April 2019

Department of Energy Resources Engineering, Research Institute of Energy and Resources, Seoul National University, Seoul, Republic of Korea. Electronic address:

Shale gas produced water is a by-product from shale gas production which causes environmental issues and needs for a wastewater treatment process. Lithium is one of the valuable metals that exists in the shale gas produced water, and it can be recovered during the water treatment process. However, the concentration of organic carbon in the produced water is significantly high, and these organic compounds may affect the lithium recovery efficiency.

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Hydrogenation of nonequilibrium alloys may form nanometer-sized metal hydride clusters, depending on the alloy compositions and hydrogenation conditions. Here in the Ti-rich compositions of the immiscible Mg-Ti system MgH clusters are embedded in a Ti-H matrix. Our previous works have indicated that the interface energy between the two metal hydrides reduces the stability of MgH.

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To develop highly efficient catalysts for dehydrogenation of formic acid in water, we investigated several Cp*Ir catalysts with various amide ligands. The catalyst with an N-phenylpicolinamide ligand exhibited a TOF of 118 000 h at 60 °C. A constant rate (TOF>35 000 h ) was maintained for six hours, and a TON of 1 000 000 was achieved at 50 °C.

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Ionic clathrate hydrates can selectively capture small gas molecules such as CO, N, CH and H. We investigated CO + N mixed gas separation properties of ionic clathrate hydrates formed with tetra-n-butylammonium bromide (TBAB), tetra-n-butylammonium chloride (TBAC), tetra-n-butylphosphonium bromide (TBPB) and tetra-n-butylphosphonium chloride (TBPC). The results showed that CO selectivity of TBAC hydrates was remarkably higher than those of the other hydrates despite less gas capacity of TBAC hydrates.

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An Overview of GIS-Based Modeling and Assessment of Mining-Induced Hazards: Soil, Water, and Forest.

Int J Environ Res Public Health

November 2017

Department of Energy Resources Engineering, Pukyong National University, Busan 48513, Korea.

In this study, current geographic information system (GIS)-based methods and their application for the modeling and assessment of mining-induced hazards were reviewed. Various types of mining-induced hazard, including soil contamination, soil erosion, water pollution, and deforestation were considered in the discussion of the strength and role of GIS as a viable problem-solving tool in relation to mining-induced hazards. The various types of mining-induced hazard were classified into two or three subtopics according to the steps involved in the reclamation procedure, or elements of the hazard of interest.

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Optimizing bicoid signal extraction.

Math Biosci

December 2017

Translational Genetics Group, Bournemouth University, Fern Barrow, Poole, BH125BB, UK. Electronic address:

Signal extraction and analysis is of great importance, not only in fields such as economics and meteorology, but also in genetics and even biomedicine. There exists a range of parametric and nonparametric techniques which can perform signal extractions. However, the aim of this paper is to define a new approach for optimising signal extraction from bicoid gene expression profile.

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Pentamethylcyclopentadienyl iridium (Cp*Ir) complexes with bidentate ligands consisting of a pyridine ring and an electron-rich diazole ring were prepared. Their catalytic activity toward CO hydrogenation in 2.0 m KHCO aqueous solutions (pH 8.

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The hydroxyl groups of a 2,2'-bipyridine (bpy) ligand near the metal center activated the catalytic performance of the Ir complex for the dehydrogenation of formic acid at high pressure. The position of the hydroxyl groups on the ligand affected the catalytic durability for the high-pressure H generation through the decomposition of formic acid. The Ir complex with a bipyridine ligand functionalized with para-hydroxyl groups shows a good durability with a constant catalytic activity during the reaction even under high-pressure conditions, whereas deactivation was observed for an Ir complex with a bipyridine ligand with ortho-hydroxyl groups (2).

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Surplus adsorption of bromide ion into π-conjugated carbon nanospaces assisted by proton coadsorption.

J Colloid Interface Sci

December 2017

Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan.

Nanoporous carbons can preferentially adsorb bromide ions from an aqueous solution of alkali metal bromides, even on π-conjugated surfaces. Our results show a new adsorption mechanism whereby coadsorption of protons enhances the adsorption of the anions onto the carbons.

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The phase behavior of ions in porous electrodes is qualitatively different from that in the bulk because of the confinement effect and the interaction between the electrode surface and the electrolyte ions. We found that porous electrodes of which the pore size is close to the size of the electrolyte ions can show ferroelectric phase behaviors in some conditions by Monte Carlo simulations of simple models. The phase behavior of the porous electrodes dramatically changes as a function of the pore size of the porous electrode and that is compared to the phase behavior of typical ferroelectric materials, for which the phase behavior changes as a function of the temperature or the composition.

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Article Synopsis
  • - The study investigates how formic acid dehydrogenation works when using a specific iridium catalyst that has a unique ligand, focusing on the reaction's kinetics.
  • - Researchers found that the rate at which the reaction occurs can change based on the concentration of formic acid and the pH, impacting which part of the reaction is the slowest (rate-limiting step).
  • - The insights gained from the research could help in developing efficient hydrogen production systems for future fueling stations, leveraging the properties of the iridium catalyst.
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We developed a novel in situ chamber to investigate the relationship between gas hydrate crystal morphology and gas permeability in a glass micromodel that mimics marine sediment. This high-pressure experimental chamber was able to use a thin glass cell without high pressure resistance. The formation of methane hydrate (MH) in the glass micromodel was observed in situ.

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Development of Proton-Responsive Catalysts.

Chem Rec

November 2017

Department of Energy and Environment, Research Institute of Energy Frontier, National Institute of Advanced Industrial Science and Technology, (AIST) Tsukuba, Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan.

A changeable ligand, which involves in activation of a catalyst or assists a reaction, draws an increasing attention, in contrast to a classical ligand as spectator. Proton-responsive catalysts, which are capable of undergoing changes of properties on gaining/losing one or more protons, provides interesting features as follows: (i) catalyst activation by electronic effect, (ii) pH-tuning of water-solubility, and (iii) second-coordination-sphere interaction. On the basis of this catalyst design concept, we developed several highly efficient proton-responsive catalysts for CO hydrogenation as H storage, formic acid (FA) dehydrogenation as H production, and transfer hydrogenation.

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Efficient Hydrogen Storage and Production Using a Catalyst with an Imidazoline-Based, Proton-Responsive Ligand.

ChemSusChem

March 2017

Research Institute of Energy Frontier, Department of Energy and Environment, National Institute of Advanced Industrial Science and Technology, Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan.

A series of new imidazoline-based iridium complexes has been developed for hydrogenation of CO and dehydrogenation of formic acid. One of the proton-responsive complexes bearing two -OH groups at ortho and para positions on a coordinating pyridine ring (3 b) can catalyze efficiently the chemical fixation of CO and release H under mild conditions in aqueous media without using organic additives/solvents. Notably, hydrogenation of CO can be efficiently carried out under CO and H at atmospheric pressure in basic water by 3 b, achieving a turnover frequency of 106 h and a turnover number of 7280 at 25 °C, which are higher than ever reported.

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Development of an Iridium-Based Catalyst for High-Pressure Evolution of Hydrogen from Formic Acid.

ChemSusChem

October 2016

Research Institute for Chemical Process Technology, Department of Material and Chemistry, National Institute of Advanced Industrial Science and Technology, Sendai, Miyagi, 983-8551, Japan.

A highly efficient and recyclable Ir catalyst bearing a 4,7-dihydroxy-1,10-phenanthroline ligand was developed for the evolution of high-pressure H gas (>100 MPa), and a large amount of atmospheric pressure H gas (>120 L), over a long term (3.5 months). The reaction proceeds through the dehydrogenation of highly concentrated aqueous formic acid (FA, 40 vol %, 10 mol L ) at 80 °C using 1 μmol of catalyst, and a turnover number (TON) of 5 000 000 was calculated.

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Selective occupancy of methane by cage symmetry in TBAB ionic clathrate hydrate.

Chem Commun (Camb)

April 2016

National Research Council of Canada, 100 Sussex Drive, Ottawa, ON K1A 0R6, Canada.

Methane trapped in the two distinct dodecahedral cages of the ionic clathrate hydrate of TBAB was studied by single crystal XRD and MD simulation. The relative CH4 occupancies over the cage types were opposite to those of CO2, which illustrates the interplay between the cage symmetry and guest shape and dynamics, and thus the gas selectivity.

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Methane hydrates (MHs) are present in large amounts in the ocean floor and permafrost regions. Methane and hydrogen hydrates are being studied as future energy resources and energy storage media. To develop a method for gas production from natural MH-bearing sediments and hydrate-based technologies, it is imperative to understand the thermal properties of gas hydrates.

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Background: Developing a sustained release drug to cure arthritis is needed. Sinomenine (SIN) is abstracted from sinomenium acutum and widely used in the treatment of various rheumatism and arrhythmia with few side effects. The primary aim of this study is to develop SIN microcapsules with polyelectrolyte multilayers for controlled drug release.

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