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951.
The US carbon allowance market has different characteristic and price determination process from the EU ETS market, since emitting installations voluntarily participate in emission trading scheme. This paper examines factors affecting the US carbon allowance market. An autoregressive distributed lag model is used to examine the short- and long-run relationships between the US carbon allowance market and its determinant factors. In the long-run, the price of coal is a main factor in the determination of carbon allowance trading. In the short-run, on the other hand, the changes in crude oil and natural gas prices as well as coal price have significant effects on carbon allowance market. 相似文献
952.
A pore-network model is developed to simulate liquid water transport in a hydrophobic gas-diffusion layer (GDL) during the operation of polymer electrolyte membrane fuel cells (PEMFCs). The steady saturation distribution in GDLs is determined through a numerical procedure using a pore-network model combined with invasion-percolation path-finding and subsequent viscous two-phase flow calculation. The simulation results indicate that liquid water transport in hydrophobic GDLs is a strongly capillary-driven process that almost reaches the pure invasion-percolation limit with zero capillary number. A uniform flux condition is found to better reflect the actual phenomenon occurring at the inlet boundary for liquid water entering a GDL than a uniform pressure condition. The simulation further clarifies the effect of the invaded pore fraction at a uniform-flux inlet boundary in modifying water transport in GDLs. Finally, the effect of the GDL thickness on the steady saturation distribution is investigated. 相似文献
953.
Kun-Ho Kim Kwan-Young Lee Hyoung-Juhn Kim EunAe Cho Sang-Yeop Lee Tae-Hoon Lim Sung Pil Yoon In Chul Hwang Jong Hyun Jang 《International Journal of Hydrogen Energy》2010
We analyzed the effects of ionomer content on the proton exchange membrane fuel cell (PEMFC) performance of membrane electrode assemblies (MEAs) fabricated by a catalyst-coated membrane (CCM) spraying method in partially humidified atmospheric air and hydrogen. When high loading Pt/C catalysts (45.5 wt.%) were used, we observed that catalytic activity was not directly proportional to electrochemical active surface area (EAS). This suggests that ionic conductivity through ionomers in catalyst layers is also an important factor affecting MEA performance. In addition, the effects of mass transport were experimentally evaluated by manipulating the air stoichiometry ratio at the cathodes. MEA performance was more sensitive to flow rates under conditions of higher ionomer content. Due to the combined effect of EAS, ionic conductivity, and mass transfer characteristics (all of which varied according to the ionomer content), an MEA with 30 wt.% ionomer content at the cathode (25 wt.% at the anode) was shown to yield the best performance. 相似文献
954.
Jong-Jin Lee Hwan MoonHae-Gu Park Dae Il YoonSang-Hoon Hyun 《International Journal of Hydrogen Energy》2010
In order to improve the performance of the anode-supported electrolyte of solid oxide fuel cells (SOFCs), the anode electrode is modified by inserting an anode functional layer of nano-composite powders between a Ni–YSZ electrode and YSZ electrolyte. The NiO–YSZ nano-composite powders are fabricated by coating nano-sized Ni and YSZ particles on the YSZ core particle by the Pechini process. The reduction of the polarization resistance of a single cell that is applied to the anode functional layer is attributed to the increasing reaction of three-phase boundaries (TPBs) within the layer and the micro-structured uniformity in the electrode. Two methods were used, namely tape-casting/dip-coating and tape-casting/co-firing, for studying the performance. It can be concluded that the cell with an anode functional layer thickness (15–20 μm) and a microstructure of NiO–YSZ nano-composite materials which was fabricated by the tape-casting/dip-coating method improved the output power (to 1.3 W cm−2) at 800 °C using hydrogen as fuel and air as an oxidant. 相似文献
955.
Sangho Sohn Jin Hyun Nam Dong Hyup Jeon Charn-Jung Kim 《International Journal of Hydrogen Energy》2010
A two-dimensional micro/macroscale model is proposed as an efficient numerical framework for simulating intermediate temperature solid oxide fuel cells (IT-SOFCs). This model employs a comprehensive microscale model that describes the detailed electrochemical reactions in Ni/YSZ cermet anodes and LSM/YSZ composite cathodes based on the three-phase boundary length (TPBL). A simplified macroscale model has been combined with the microscale model to consider the heat and mass transport processes in IT-SOFCs with prescribed fully-developed laminar velocity profiles in gas channels. A hydrogen-fed IT-SOFC is simulated at various operating conditions in order to demonstrate the capabilities of the proposed micro/macroscale model. The results elucidate the effects of co- and counter-flow configurations, inlet temperature, and air and fuel flow rates on the performance of the IT-SOFC. 相似文献
956.
Bioavailability of Isoflavone Metabolites After Korean Fermented Soybean Paste (Doenjang) Ingestion in Estrogen‐Deficient Rats
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Da‐Hye Lee Min Jung Kim So‐Hyun Park Eun‐Ji Song Yong‐Do Nam Jiyun Ahn Young‐Jin Jang Tae‐Youl Ha Chang Hwa Jung 《Journal of food science》2018,83(8):2212-2221
Doenjang (DJ), a fermented soybean product used in soups, stews, and sauces, contains high quality proteins, fats, vitamins, minerals, and other functional ingredients, including isoflavones and saponins. This study investigated whether DJ improves the bioavailability of isoflavones compared to boiled soybean (BS) in sham‐operated or ovariectomized (OVX) rats. We also examined the effects of ovariectomy on the differences in bioavailability of isoflavones. BS and DJ were administered in sham‐operated and OVX rats, and blood samples were collected. Twenty‐six isoflavone‐derived metabolites were identified. Pharmacokinetic analysis revealed that T1/2 values of the individual isoflavone metabolites were most different in sham and OVX rats, even after the same sample treatment; however, Tmax values were significant different in a few metabolites such as daidzein 4′‐glucuronide, daidzein 4′‐sulfate, 2‐(4‐hydroxyphenyl)propionic acid, and benzoic acid. For most of the individual metabolites, Cmax was higher in both sham and OVX rats administered BS than those administered DJ. The AUC was generally lower in OVX rats than in sham rats. The AUC of daidzein and genistein in BS‐fed sham rats was approximately 1.7‐fold higher than those administered DJ, whereas glycitein was detected only in the DJ group. No significant differences in AUC of daidzein and genistein were observed between BS and DJ administration in OVX rats, although the total isoflavone content of DJ was lower; thus, DJ‐mediated isoflavone bioavailability was more effective in OVX rats. Similar tendencies were observed for phase II and gut‐mediated metabolites. These results suggested that DJ enhanced isoflavone bioavailability under estrogen deficiency, even when the total isoflavone content was decreased by fermentation. 相似文献
957.
Fermentation of soybean hull by Monascus pilosus and elucidation of its related molecular mechanism involved in the inhibition of lipid accumulation. An in sílico and in vitro approach
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958.
959.
Ju Hyun Lee Michael J. Ostwald William D. Sher Hyunsoo Lee 《International Planning Studies》2017,22(3):205-225
Whilst the generic visions and directions of urban regeneration in cites are well documented, far less is understood about the strategic approaches to this issue which are being used in specific urban contexts. This paper investigates strategic planning schemes (SPSs) and visions for mixed-use development to support urban regeneration in Seoul (South Korea), using a combination of a literature review and a survey. The results contribute to understanding the construction of SPSs for future urban development as well as to improving strategic planning for urban regeneration on a wider scale. 相似文献
960.
Evaluation of fungal microflora for aflatoxin producing possibility in novel quality Meju fermented with single and/or multiple additions of Nelumbo nucifera,Ginkgo biloba,and Allium sativum extracts
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