• Title/Summary/Keyword: storage environment

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High Alloying Degree of Carbon Supported Pt-Ru Alloy Nanoparticles Applying Anhydrous Ethanol as a Solvent

  • Choi, Kwang-Hyun;Lee, Kug-Seung;Jeon, Tae-Yeol;Park, Hee-Young;Jung, Nam-Gee;Chung, Young-Hoon;Sung, Yung-Eun
    • Journal of Electrochemical Science and Technology
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    • v.1 no.1
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    • pp.19-24
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    • 2010
  • Alloying degree is an important structural factor of PtRu catalysts for direct methanol fuel cells (DMFC). In this work, carbon supported PtRu catalysts were synthesized by reduction method using anhydrous ethanol as a solvent and $NaBH_4$ as a reducing agent. Using anhydrous ethanol as a solvent resulted in high alloying degree and good dispersion. The morphological structure and crystallanity of synthesized catalysts were characterized by X-ray diffraction (XRD), high resolution transmission electron microscope (HR-TEM). CO stripping and methanol oxidation reaction were measured. Due to high alloying degree catalyst prepared in anhydrous ethanol, exhibited low onset potential for methanol oxidation and negative peak shift of CO oxidation than commercial sample. Consequently, samples, applying ethanol as a solvent, exhibited not only enhanced CO oxidation, but also increased methanol oxidation reaction (MOR) activity compared with commercial PtRu/C (40 wt%, E-tek) and 40 wt% PtRu/C prepared in water solution.

Studies on Germination Rates and Early Seedling Growth Characteristics by Different Storing Temperatures, Durations, and Methods in Aralia cordata var. continentalis (Kitagawa) Y.C.Chu (독활 종자의 저장온도, 기간 및 방법에 따른 발아율과 유묘 생육특성 연구)

  • Lee, Gyeong A;Kim, Do Hyun;Kim, Min Su;Wu, Wen Guo;Kim, Young Gook;Ahn, Young Sup;Park, Chung Beom;Song, Beom Heon
    • Korean Journal of Medicinal Crop Science
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    • v.21 no.1
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    • pp.20-26
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    • 2013
  • This study was conducted to improve the managing and storing methods of the seeds of Aralia cordata var. continentalis (Kitagawa) Y.C.Chu, to examine the viability and the germination ability of seeds with different storing conditions and methods, and to develop new ways to propagate and have better healthy seedling. Therefore, the germination rate, days required for germinating seeds, and early growth responses of Aralia cordata var. continentalis (Kitagawa) Y.C.Chu were investigated with different storing temperatures, durations and methods. The germination rate was higher in stratified storage than that in dry storage condition. The highest germination rate was with outdoor temperature at 30 days after stratified storage. The days required for germinating seeds were less than 10 days with the treatment of $25^{\circ}C$ and outdoor temperature in stratified storage. In dry condition, they were shorter with $4^{\circ}C$ and $25^{\circ}C$ than those with $-20^{\circ}C$ and outdoor temperature. Leaf number of seedling was higher in stratified storage compared to that in dry condition, while it was not clearly different according to storage temperatures and durations. Leaf length and leaf width of seedling was not difference among the treatment of storage methods, temperatures, and durations. Stem length of seedling was higher in stratified storage than those in dry condition, while root length was not clearly different among the treatments. It would be assumed that temperatures, methods and durations of storage could affect much to the germination rate and the early seedling growth response.

Effect of Polypropylene Film Package and Storage Temperature on the Shelf-life Extension of Spinach (Spinacia oleracea L.) (시금치 포장 및 보관온도가 품질보존에 미치는 영향)

  • Choi, Dong-Jin;Lee, Suk-Hee;Yoon, Jae-Tak;Sim, Yong-Gu;Oh, Seok-Gui;Jun, Ha-Joon
    • Journal of Bio-Environment Control
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    • v.16 no.3
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    • pp.247-251
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    • 2007
  • To extend the shelf-life of spinach after harvest, we investigated the effect of various packaging methods and storage temperature. In case of polypropylene film package, there was no weight loss, but in non-package, remarkably weight loss occurred as storage period extended and storage temperature risen. Content of vitamin C was decreased rapidly at early stage of storage, and decrease of vitamin C in low temperature storage was lower than that of room temperature storage, but its large difference according to packaging method was not observed. In hunter's value on spinach, b value in room temperature storage was higher than that of low temperature storage. In terms of freshness, shelf-life of spinach by low temperature storage $(1{\sim}3^{\circ}C)$ after PP film packaging lasted 34 days, and that by room temperature storage $(10{\sim}15^{\circ}C)$ after PP film packaging lasted 8 days, but that by room temperature storage after non-packaging lasted 3 days.

Technology for AR Dry Storage of Spent Fuel (원전부지내 사용후핵연료 건식저장기술 분석)

  • Lee, Heung-Young;Yoon, Suk-Jung;Lee, Ik-Hwan;Seo, Ki-Seog
    • Journal of Radiation Protection and Research
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    • v.21 no.4
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    • pp.313-327
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    • 1996
  • As an at-reactor(AR) storage method o( spent fuel, there are horizontal concrete module type, metal storage cask type, concrete storage cask type, dual purpose (transportation and storage) cask type and multi-purpose (transportation, storage and disposal) cask type. All other types except multi-purpose one have been already used for AR dry storage of spent fuels after obtaining operation license in various foreign countries. Also the development of multi-purpose type has been continued for operation license. In America, Japan, Germany, Canada, Spain, Switzerland, and Czech Republic, etc., AR dry storage facilities are under operation or on propulsion, and spent fuels are transported to interim storage facility or reprocessing plant after dry storage at reactor temporarily. At Wolsung site, in case of Korea, concrete silo type has already been introduced, and it is believed to be inevitable to store spent fuels at reactor temporarily, considering the reality that storage capacity of spent fuel is approaching to the limit in some nuclear power plants. In this report, the system characteristics, design requirements, technical standards and status of AR storage system, which is suitable for domestic site such as Kori, have been studied. In most cases, the licensed period of storage cask is limited up to 20 years and the integrity of material and maintenance of leaktightness are required during the whole service life.

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Comparative Analysis of the Storm Sewer Expansion Methodology and Underground Rainwater Storage Tanks for Urban Flood Control (기존 도시의 홍수저감을 위한 우수관거 배수용량 증대 및 지하 빗물저류조 설치효과 비교 분석)

  • Lee, Ho Yeol;Seo, Gyu Tae;Lee, Taek Soon
    • Journal of Korean Society on Water Environment
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    • v.29 no.6
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    • pp.754-761
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    • 2013
  • Urban floods are usually caused by the lack of drainage capacity. Hence, sewer capacity expansion methodology by replacing small pipes with bigger ones is primarily applied as a flood control measure. However, this approach is often unreasonable because of the costs and time involved. Thus, the installation of underground rainwater storage tanks with the two advantages of flood control and water conservation is proposed. This study compared the effectiveness of flood control by both the sewer expansion methodology and rainwater storage tanks using the Storm Water Management Model. Three cases were simulated in this study. The first case analyzed flood reduction by the storm sewer expansion methodology. The simulation results indicate that the overflow volume from manholes was reduced by 49% with this methodology. The second case analyzed flood reduction by installation of rainwater storage tanks. The simulation results indicate that the overflow volume was reduced by 62%. However, these two cases could not prevent urban floods completely. Hence, the third case analyzed the joint application of the storm sewer expansion methodology and rainwater storage tanks. In this simulation, flooding did not occur. Consequently, the results of this study clearly show that underground rainwater storage tanks are more effective for flood control than capacity expansion of storm sewer. Furthermore, the joint application of these two flood control measures is more effective than their separate application.

Change of the Concentration of Pesticide Residues in Pepper Powder by Storage Temperature and Storage Period (저장온도와 기간에 따른 고춧가루 중 농약의 잔류량 변화)

  • Jo, Sung-Ae;Kim, Eun-Hee;Kim, Kyung-Sig;Kim, Jung-Hun;Park, Seog-Gee
    • The Korean Journal of Pesticide Science
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    • v.13 no.3
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    • pp.127-132
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    • 2009
  • The purpose of this study is to examine changes in the pesticides residues in pepper powder by storage conditions. Analysis of pesticide residues was performed using multiresidue analytical methods and the number of pesticides detected from 60 pepper powders was 7 pesticides such as cypermethrin, fenvalerate, kresoxim-methyl, chlorpyrifos, chlorfenapyr azoxystrobin, tebuconazole. The concentrations of cypermethrin and tebuconazole were exceeded their maximum residue limits (MRLs). The degradation patterns of pesticides at $-5^{\circ}C$ were compared to those at $20^{\circ}C$ and $4^{\circ}C$. Without reference to storage temperature, degradation rates of azoxystrobin and fenvalerate were above 80%. Degradation rate of chlorpyrifos was 47% at storage $4^{\circ}C$, $20^{\circ}C$ and 34% at storage $-5^{\circ}C$. During each storage peroid, the degradation patterns were more lower at $-5^{\circ}C$ than at $20^{\circ}C$ and $4^{\circ}C$.

Analysis of blue carbon storage research trends and consideration for definitions of blue carbon: A review (블루카본 저장 연구 동향 분석 및 블루카본의 정의에 대한 고찰: 리뷰)

  • Kyeong-deok Park;Dong-hwan Kang;Won Gi Jo;Jun-Ho Lee;Hoi Soo Jung;Man Deok Seo;Byung-Woo Kim
    • Journal of Wetlands Research
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    • v.26 no.1
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    • pp.82-91
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    • 2024
  • In this study, research cases related to blue carbon storage were collected and analyzed, and various definitions of blue carbon were considered in terms of spatiotemporal scope and scientific aspect. 444 papers were selected as research cases related to blue carbon storage, and analysis of the number of papers published by year/country and keywords was performed. Publication of papers related to blue carbon storage has continued to increase since 2011, and more than 50 papers have been published annually since 2018. The most publications by country were in Australia with more than 100 papers, and the United States and China also published more than 60 papers. Key terms related to "natural environment" and "storage characteristics" were analyzed in the sentences defined in the 23 papers that presented the definition of blue carbon. The natural environments where blue carbon was stored were mostly mangroves, salt marshes, and seagrass beds, and blue carbon repository included sediments and even plants themselves. The existing definition of blue carbon focused on the vegetation environment as the storage environment for blue carbon. However, since blue carbon is stored in the sediments of coastal wetlands, it would be appropriate to define the coastal ecosystem, including non-vegetated mudflats, as the storage environment for blue carbon.

Pyruvic Acid and Sugar Contents during Storage Duration in Onion (Allium cepa L.) (양파 저장 중의 Pyruvic Acid와 당 함량의 변화)

  • Lee, Eun-Ju;Jeon, Jae-Kyung;Suh, Jun-Kyu
    • Journal of Bio-Environment Control
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    • v.19 no.4
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    • pp.377-381
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    • 2010
  • This study was carried out to access the stauts of pyruvic acid and sugars in onion bulbs during storage at room temperature. Pyruvic acid content remained in a steady state until 3 months of storage. However the pyruvic acid content gradually increased as the onions started to root, and rapidly increased after sprouting. There was no difference in dry matter contents during storage.e. Sucrose content increased as storage duration extended, and then gradually decreased right after the onions started to sprout. Fructose content gradually decreased after 45 days of storage, and remained in a steady state after sprouting. Glucose content had a tendency to increase as storage duration extended. Pyruvic acid/total sugar (PA/TS) ratio decreased after 1 month of storage, and then increased after 135 days, and was 83% higher at 150 days of storage than at harvest. Sweetness gradually decreased until 1 month of storage, but thereafter remained steady. Therefore it is desirable that pyruvic acid analysis for sweet onion selection should be conducted before breaking the dormancy.

Design and Implementation of Software-Defined Storage Autoconfiguration Module for Integrated Use of Cloud File/Block/Object Storage (클라우드 파일/블록/객체 스토리지의 통합사용을 위한 소프트웨어 정의 스토리지 자동 설정 모듈의 설계 및 구현)

  • Park, Sun;Cha, ByungRae;Kim, Jongwon
    • Smart Media Journal
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    • v.7 no.4
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    • pp.9-16
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    • 2018
  • In order to improve the economics and flexibility of cloud computing, tendency to automate the operation and management of cloud resources has become complicated. However, while automation for cloud storage depends on the manufacturer's storage hardware, it cannot flexibly support the storage type in accordance with users' needs. In this paper, we propose an automatic configuration module that supports block/file/object storages suitable for user environment. In order to automatically install ceph, a cloud storage, we propose an automatic installation and configuration module based on the Chef configuration management tool. In addition to that, we also propose an automatic configuration module based on a shell programming in pursuit of enabling users to use ceph storage of block/file/object. The proposed method can automatically set up and manage shared file, block, and object storages in a virtual or physical user environment with no hardware dependencies.

Object-based Multimedia Contents Storage for Mobile Devices

  • Nam, Young-Jin;Choi, Min-Seok;Nam, In-Gil
    • Proceedings of the Korea Society of Information Technology Applications Conference
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    • 2005.11a
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    • pp.31-34
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    • 2005
  • Mobile devices, such as PDAs, portable multimedia players, are more likely to encompass large storage devices with prevalance of high-quality multimedia contents. This paper proposes an object-based multimedia contents storage architecture that employs the object-based storage device model and the iSCSI protocol. It also provides a multimedia content player that operates directly with the proposed storage architecture. We implement both the proposed storage architecture and the multimedia content player upon the Linux environment. Performance evaluation by playing MP3 multimedia contents reveals that the proposed storage architecture reduces the total power consumption by 9%, compared with an existing networked storage. This enhancement is mainly contributed to the fact that a large portion of the file system is moved into the object-based multimedia contents storage from the mobile device.

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