• Title/Summary/Keyword: Dry method

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Feasibility Study of a Device for Decladding and Dry Pulverizing/Mixing Spent Fuel (사용후핵연료의 탈피복 및 건식 분말화/혼합 장치의 타당성 분석)

  • 정재후;윤지섭;홍동회;김영환;박기용;진재현
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.840-843
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    • 2002
  • The dry pulverizing/Mixing device is used to deal with the spent fuels for the safe disposal. The separated pellets from hulls by a slitting device are put and oxidized from UO$_2$ solid pellet to U$_3$O$\_$8/ powder in the device. The device have been developed based on a voloxidation method which is one of several dry de-cladding methods. We have benchmarked dry de-cladding methods, analyzed applicability to the advanced spent fuel management process, integrated and compared several configuration, and finally derived detailed specifications proper to requirements for the device. Also, thermal characteristics of the device such as thermal stress and strain have been analyzed by the commercial software, 1-DEAS, and the reliability of the results have been verified by the KOLAS(Korea Laboratory Accreditation Scheme). The UO$_2$ solid pellets are put in the device which has a capacity of 20 kgHM per a batch, heated up about 600$^{\circ}C$ in the air environment. Then, the UO$_2$ solid pellets are oxidized into the U$_3$O$\_$8/ powder, and the powder is collected in a special vessel. The device has been designed and developed as fellows: the multi-staged fine hole meshes are used to reduce the size of the powder gradually, heat and air(oxygen) are supplied continuously to reduce the reaction time, and slight vibration effect are applied to collect powder cling to the device.

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Estimation of Wood Oven-Dry Density by Using a Portable Dielectric Moisture Meter (휴대용 유전율식 수분계를 이용한 목재의 전건밀도 추정)

  • Kang, Chun-Won;Lim, Ho-Mook;Kang, Ho-Yang
    • Journal of the Korean Wood Science and Technology
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    • v.45 no.5
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    • pp.629-639
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    • 2017
  • Tripitaka Koreana in Haein Temple, Hapcheon Province is the most historical and largest heritage in this country, however the species of their blocks have yet been unknown. A nondestructive test method is necessary to investigate their species. The oven-dry density of wood was measured by inversely using the principle of high frequency moisture meter. The oven-dry densities of more than 100 domestic species of specimens estimated by measurement method and high frequency moisture meter were compared and following conclusions were obtained. There was highly close correlation between the oven-dry density estimated by measurement method and the oven-dry density estimated by high frequency moisture meter. The densities of Tripitaka Koreana that was a global cultural heritage could be correctly estimated by using high frequency moisture meter and the equilibrium moisture content under which Tripitaka Koreana equilibrated, thus, it was expected to provide the key to species identification.

Water Contact Angles of Graphene Transferred by Wet and Dry Transfer Methods (전사 방법에 따른 그래핀의 물 접촉각 변화)

  • Yoon, Min-Ah;Kim, Chan;Jung, Hyun-June;Kim, Jae-Hyun;Kim, Kwang-Seop
    • Tribology and Lubricants
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    • v.34 no.2
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    • pp.60-66
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    • 2018
  • Graphene is a monolayer of carbon atoms (approximately 0.34 nm), arranged in a honeycomb network. It has been hailed as a next-generation flexible and transparent material because it has high electrical and thermal conductivities, excellent mechanical properties, as well as flexible and transparent properties. The wettability of graphene alters its adhesion or surface energy, and it is therefore an important parameter influencing its application in the fabrication of next-generation flexible and transparent electronics. Studies on the wettability of graphene are numerous and various opinions exist. However, almost all of these studies use the wet transfer method to transfer the graphene. In this study, therefore, we investigated the effect of wet and dry transfer methods on water contact angles of graphene on a substrate. The contact angles of substrates vary depending on the type of substrate. It was found that after graphene is transferred to the substrate, regardless of transfer method, the graphene/substrate contact angle increases to a value. The contact angle of graphene transferred using the dry transfer method is higher than the contact angle of graphene transferred using wet transfer methods. The wet transferred graphene is affected by the poly(methyl methacrylate) (PMMA) residue and the polar surface of substrate. The dry transferred graphene is influenced by the conformal contact between graphene and substrate.

Optimal Design of Carbon Dioxide Dry Reformer for Suppressing Coke Formation (코크 생성 억제를 위한 이산화탄소 건식 개질 반응기의 최적 설계)

  • Lee, Jongwon;Han, Myungwan;Kim, Beomsik
    • Korean Chemical Engineering Research
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    • v.56 no.2
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    • pp.176-185
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    • 2018
  • As global warming accelerates, greenhouse gas reduction becomes more important. Carbon dioxide dry reforming is a promising green-house gas reduction technology that can obtain CO and $H_2$ which are high value-added materials by utilizing $CO_2$ and $CH_4$ which are greenhouse gases. However, there is a significant coking problem during operation of the dry reforming reactor. Because the carbon dioxide dry reforming is a strong endothermic reaction, the temperature of the reactor drops near the reactor inlet and causes coke formation. To solve this problem, it is important to ensure that the reaction takes place in a temperature range where coke production is minimized. In this study, we proposed a design method that can maintain reaction temperature in the region where the coke is rarely generated by using the new catalyst configuration method. The design method also optimizes the reactor by solving the optimization problem which minimizes the reactor length for a given reaction conversion by using the fuel flow rate, catalyst density, and output temperature by section as optimization variables.

Systematic Review of Moxibution Treatment for Dry Eye Syndrome (안구건조증의 뜸 치료에 대한 체계적 문헌 고찰)

  • Lee, Ho-Chan;Lee, Yu-Lim;Ko, Hong-Je;Choi, Jung-Hwa;Jeong, Min-Yeong;Park, Soo-Yeon
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.32 no.1
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    • pp.42-58
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    • 2019
  • Objectives : The aim of this study is to review the methodology of clinical trials conducted with the acupuncture and moxibustion treatment on Dry eye syndrome. Methods : Through four foreign online databases(PubMed, Cochrane library, EMBASE, CNKI) and two domestic online databases(NDSL, OASIS), we searched for clinical studies that performed moxibustion for dry eye syndrome from 2000 to December 2018. Only randomized controlled trials(RCT) were selected and anlyzed according to the research method. Results : A total 12 studies were reviewed and conducted in China. BL1, ST2, BL2 were most frequently used acupoints in moxibustion treatment. Among the evaluation indexes, Schirmer I Test(SIT), Tear break-up time(BUT) were used most. In most of the 12 studies, moxibustion treatment showed significant therapeutic effects. Conclusions : These results suggest that it is necessary to develop more detailed standards about moxibustion treatment method as the method of moxibustion is getting more diverse, and objective tools are needed in evaluating dry eye syndrome.

Fabrication of Mn-Zn Ferrite by Hot Petroleum Drying Method (석유증발 건조방법에 의한 Mn-Zn Ferrite의 제조에 관한 연구)

  • 변수일
    • Journal of the Korean Ceramic Society
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    • v.16 no.2
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    • pp.69-76
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    • 1979
  • This study attempted to characterize the powder and sintered specimen of Mn-Zn ferrite that was prepared by Hot Petroleum Drying Method. The results of the experiment were as follows: 1. The mixed sulfate powder prepared by Hot Petroleum Drying Method was homogeneous and very reactive. The ferrite formation of this powder occurred at lower temperature than the one prepared by Sulfate Dry Mixing Method. 2. The calcined oxide powder prepared by Hot Petroleum Drying Method was found to be agglomerated, and therefore it was very difficult to compact this powder. 3. The sintered density was 4.95g/㎤, 97% of the theoretical density, when the specimen was prepared by Hot Petroleum Drying method, calcined at 90$0^{\circ}C$ in air for 3h, sintered at 1,30$0^{\circ}C$ in air for 3h, and then cooled in nitrogen. 4. The discontinuous grain growth occurred at lower temperature in the specimen prepared by Hot Petroleum Dyring Method than in the one prepared by Sulfate Dry Mixing Method. The discontinuous grain growth was considered to be due to the presence of liquid formed by addition of CaO and $SiO_2$.

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A Study on the Improvement of Wall Execution Method on Hanok (한옥 축부(軸部) 시공법 개선 연구)

  • Kim, Do-Kyoung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.7
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    • pp.2670-2675
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    • 2010
  • Wall of hanok is related to exterior, inner environment, and the period and cost of construction. This study analyzes traditional wall execution method and suggests improved one. The characters of the improved execution method are use of ready made goods, application of dry and prefabricated method and improvement of airtightness and insulation capacity etc. The result of this study needs production of pilot productions and tests of capacity. But this new method will be useful to save the period and cost of hanok construction.

Evaluation of Friction and Hydroplaning Characteristic in Aifield Using Dry Grooving Method (건식그루빙을 사용한 공항 활주로의 마찰 및 수막현상 특성평가)

  • Park, Tae-Soon
    • International Journal of Highway Engineering
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    • v.3 no.3 s.9
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    • pp.111-118
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    • 2001
  • Since the advent of turbojet aircraft with their greater weight and high landing speed breaking performance on runway surface has become un critical. Under certain weather conditions(wet weather, winter) hydroplaning or unacceptable loss of traction can occur, resulting in poor braking performance and possible loss of directional control. To address this concern a number of research project me conducted by NASA, FAA, USAF. The various method which was reported the advantage of the increasing the friction and decreasing the hydroplaning effect. A-2 section of inchon international airport was grooved using drying grooving method. In order to evaluate the effectiveness of the dry grooving method the surface was spray with water and measured the fiction factor and the depth of the water using Mu meter and water depth measuring device. The field test results shooed that the fiction factor nos increased and the depth of the water decreased. The dry grooving method illustrated the reduction of hydroplaning and also, no distress on the runway.

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Optimization of Pre-treatment Process for Manufacturing Apple Jangachi (사과장아찌 제조를 위한 전처리 공정의 최적화)

  • Oh, Chul-Hwan
    • Culinary science and hospitality research
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    • v.24 no.1
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    • pp.105-113
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    • 2018
  • In this study, optimized pre-treatment conditions were investigated to improve the quality of gochujang apple jangachi. The moisture content was decreased by 14% in 60% sugar solution and 17% in 30% salt solution during 12 hours. On the one hand, in the case of dry sugar and salt method, moisture content was decreased rapidly by 20% and 24%, respectively during 12 hours. Compared with the sugar and salt solution method, the dry sugar and salt method was more effective in reducing moisture content during 12 hours. In the case of osmotic dehydration of the apple parts in the dry sugar method, the moisture content of the flesh, flesh including peel, and peel of apple decreased by 23%, 20%, and 16%, respectively during 6 hours. However, in the dry salt method, the moisture content of the flesh, flesh including peel, and peel of apple decreased by 19%, 12% and 13%, respectively during 2 hours. During this time, the pH tended to decrease, regardless of the presence of sugar and salt. Total acidity was slightly increased in the case of salt. In hot air drying after osmotic dehydration, the moisture content of flesh including peel of apple decreased from 64% and 67% to 31% and 27%, respectively at 90 minutes, and from 64% and 67% to 11% and 18% at 150 minutes, respectively. The moisture content of the peel decreased from 51% to 10% at 120 minutes. As a result of the sensory evaluation, the overall acceptance of the flesh and flesh including peel was highly evaluated, resultantly, the products were considered to be suitable for the production of gochujang apple jangachi.

Changes in Cholesterol Contents of Kwamaegi Flesh by Drying Methods of Pacific saury, Cololabis saira (건조조건에 따른 꽁치과메기의 콜레스테롤 함량 변화)

  • O, Seung-Hui;Ha, Tae-Ik;Jang, Myeong-Ho
    • The Korean Journal of Food And Nutrition
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    • v.9 no.3
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    • pp.271-274
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    • 1996
  • New drying method was tested for the Quality control for Kwamegl, dry Pacific saucy(Cololahis saira) In east coast area of Kyungbuk province, Korea. Cholesterol content of raw fish was 56% on dry basis, and decreased to 50.82 mg% rapidly the first 3 day and then, it was almost unchanged. However, the cholesterol content decreased slowly to 52.3 mg% during 15 days in new artificial drying.

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