• Title/Summary/Keyword: homemade

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A scintillation detector configuration for pulse shape analysis

  • Van Chuan, Phan;Hoa, Nguyen Duc;Hai, Nguyen Xuan;Anh, Nguyen Ngoc;Dien, Nguyen Nhi;Khang, Pham Dinh
    • Nuclear Engineering and Technology
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    • 제50권8호
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    • pp.1426-1432
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    • 2018
  • This paper presents a neutron detector configuration using EJ-301 scintillation liquid, a R9420 photo-multiplier and a homemade preamplifier. The detector qualities which include the energy linearity, efficiency response and neutron/gamma discrimination are guaranteed for neutron detection in the energy range from 0 to 3000 keVee. Regarding the neutron/gamma discrimination capability, four pulse shape discrimination (PSD) methods which are the threshold crossing time (TCT), pulse gradient analysis (PGA), charge comparison (CC) and correlation pattern recognition (CPR), were evaluated and discussed; among of these, the CPR method provides the best neutron/gamma discrimination.

Impact of geometrical parameters on SGEMP responses in cylinder model

  • Chen, Jian-Nan;Zhang, Jun-Jie
    • Nuclear Engineering and Technology
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    • 제54권9호
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    • pp.3415-3421
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    • 2022
  • This paper is aimed to find out the impact of the geometrical parameters, mainly the radius and the height of a cylinder, on the SGEMP response including the famous scaling law in the classical cylinder model using a homemade PIC code UNIPIC-3D. We computed the electric fields at the center and at the edge on the emission head face with different radii and heights under normal X-rays incidence. The results show that the electric field will increase with the radius but decrease with the height. We analyze the scaling law that links the electric field product and fluence product, and whereafter an irreconcilable contradiction raises when the radius is changeable, which limits the application range of the scaling law. Moreover, the field-height-radius relation is found and described by a combination of logarithmic and minus one-quarter numerical fitting law firstly. Particle and magnetic field distributions are used to explain all the behaviors of the fields reasonably. All the findings will assist the evaluation of SGEMP response in spacecraft protection.

Hybrid type Na-air battery를 위한 촉매들의 제조 및 전극 계면 반응 성능 비교 (Preparation of Electrocatalysts and Comparison of Electrode Interface Reaction for Hybrid Type Na-air Battery)

  • 김경호
    • 접착 및 계면
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    • 제22권1호
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    • pp.1-7
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    • 2021
  • 신재생 에너지 발전을 통한 안정적인 전력 공급을 위해 대용량 에너지 저장 장치의 중요성이 최근 부각되고 있다. 이러한 관점에서 차세대 이차 전지인 Na-air battery (NAB)는 풍부하고 저렴한 원재료를 통해 대용량을 구현할 수 있어 많은 관심을 받고 있다. 본 연구에서는 Hybrid type Na-air battery를 위한 활성탄 기반 촉매들을 제조하여 이들의 특성을 비교 분석하였다. 특히, 자원 재활용의 관점에서 버려진 오렌지 껍질을 사용하여 활성탄(Orange-C)과 이를 질소를 이용하여 도핑한 활성탄(N-doped-Carbon, Nd-C)을 제조하였으며, 널리 사용되고 있는 Vulcan카본과 성능을 비교하였다. 또한, 제조한 활성탄(Nd-C)이 지지 촉매로 활용 가능한지 확인하기 위해 수정된 폴리올법을 사용하여 Pt/C 촉매(homemade-Pt/C, HM-Pt/C)를 합성하였으며, 상용화된 Pt/C 촉매(Commercial Pt/C)와 전기화학적 성능을 비교하였다. 제조된 Orange-C와 Nd-C는 전형적인 H3 타입 BET isotherm을 보였으며, 이는 마이크로 기공과 메조기공이 존재한다는 증거이다. 또한, HM-Pt/C의 경우, 활성탄(Nd-C) 지지 촉매 위에 Pt 입자가 고르게 분포하고 있음을 TEM 분석을 통해 확인할 수 있었다. 특히, HM-Pt/C 기반의 NAB의 경우, 1st galvanostatic charge-discharge 시험에서 가장 작은 Voltage gap (0.224V)과 우수한 Voltage efficiency (92.34%)를 보였다. 또한, 20사이클 동안 진행한 사이클 성능 시험에서도 가장 안정적인 성능을 보였다.

Conservation of the Old Hat

  • Im Sung-Kyung;Han Myung-Sook
    • The International Journal of Costume Culture
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    • 제7권2호
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    • pp.151-157
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    • 2004
  • This research is to conservate the old hat and restore its shape and place it on a supportive form in a stable protective container. The hat is a homemade construction, utilizing three different machine made laces, and two cotton net fabrics. The exterior, particularly the top crown piece, as well as the lace along the brim's edge has been generally soiled and discolored. Inside the crown, the cotton net has broken threads, and thread loss in several areas. The paper covering the two wires is very weak, and has discolored the lace in the areas of contact. The plastic buckles of the velvet ribbon have also discolored the areas where there is contact. The wash/bleach bath procedure was very effective. Virtually all of the light brown surface discoloration stains were removed. The darker brown spots, particularly concentrated around the two paper covered wires and assumed to be rust, were $90\%$ removed by the treatment. The brown spots apparently were due to the degradation of the paper covering, and not caused by the wire itself. The buckram foundation lost about $50\%$ of its stiffness, but this was not a major concern due to the fact that this hat should remain it its mount, which has been designed to serve for both storage and exhibition purposes.

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미취학아동의 우식활성과 구강위생습관의 상관성에 관한 연구 (RELATION BETWEEN CARIES ACTIVITY AND ORAL HYGIENE HABITS IN PRESCHOOL CHILDREN)

  • 조선아;이광희;김대업;정영석
    • 대한소아치과학회지
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    • 제24권1호
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    • pp.247-264
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    • 1997
  • 501 preschool children from 4 to 6 years were examined for their salivary reductase activity and caries experience by Resazurin Disc Test and dental examination respectively. We asked the parents about their children's oral hygiene habits, between-meal eating habits, and physical exercise habits by the questionnaire. Toothbrushing frequency had negative relation to salivary reductase activity and caries experience. Caries experience was low when parents did toothbrushing for children, when teeth were brushed at bedtime, and when fluoride toothpastes were used. Salivary reductase activity and caries experience were high in bread & cookies group, chocolates & candies group, milk & soft drink group, and fruits & vegetables group in order. Caries experience was high in case of irregular between-meal eating. Sweet food eating frequency had positive relation to caries experience. Caries activity was low in case of eating homemade non-sweet between-meals. Salivary reductase activity and caries experience were low when gum-chewing frequency was high. Salivary reductase activity and caries experience were high when the amount of physical exercise was low.

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박막 재료 시험기 개발 및 응용 (Development and Applications of Material Testers for the Thin Films)

  • 안현균;이학주;오충석
    • 한국정밀공학회지
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    • 제23권3호
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    • pp.163-170
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    • 2006
  • Thin films play an important role in many technological applications including microelectronic devices, magnetic storage media, MEMS and surface coatings. It is well known that a thin film's material properties can be very different front the corresponding bulk properties and thus there has been a strong need for the development of a miniature tester to measure the mechanical properties of a thin film. Two testers are designed and set up in small size of 62 mm width, 20 mm depth and 90-120 mm height to fit in a chamber of scanning electron microscope (SEM). One tester has a homemade 0.2 N load cell and a low-priced electromagnetic actuator. The other has a commercial 5 N load cell, a $52{\mu}m$ piezoelectric actuator and some novel grips. Two types of 3.5 microns thick polysilicon specimen are tested to prove the testers' applicability. The strain is measured by the two ways. Firstly, it is measured by an ISDG system in the atmosphere far the reference. Secondly, the same test is repeated in a SEM chamber to monitor the strain as an in-situ experiment. The strain is evaluated by observing the gap change between two markers.

장시간 심폐소생술을 요한 초오중독에 의한 심정지 1례 (Prolonged Cardiopulmonary Resuscitation in a Cardiac Arrest Patient with Aconitine Intoxication)

  • 황인우;정태오;이재백;진영호
    • 대한임상독성학회지
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    • 제5권1호
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    • pp.67-70
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    • 2007
  • Aconitum is an extremely dangerous plant that contains various toxic diterpenoid alkaloids, primarily concentrated in the roots. We report a case of acute intoxication of a 60-year-old man admitted to our emergency department after ingestion of a large amount of homemade aconitine decoction. At presentation about one hour after intake, the patient was unconscious and electrocardiographic analysis showed a ventricular tachycardia/fibrillation. Several times defibrillation was applied and antiarrhythmic agents were administered, but the patient still exhibited a refractory ventricular fibrillation and failed to return to spontaneous circulation. Sustained cardiopulmonary resuscitation finally produced a pulsatile cardiac rhythm at two hours after intake. The patient was discharged from our hospital on day 8. The authors stress that clinicians must be aware of the possible occurrence of life-threatening ventricular arrhythmia in cases of aconitine intoxication and be prepared to persist with prolonged CPR as necessary.

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Engine 폐유 자원순환 기술에 관한 연구 (A study for cyclic Process technique of mineral base engine used oil resource)

  • 김주항
    • 기술사
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    • 제18권2호
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    • pp.6-15
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    • 1985
  • A new process disregraded the H$_2$SO$_4$ treatment process heretofore in use, was developed and substituted for mineral base engine used oil of homemade SAE-30 grade H.V.I., which was used covering 4,500km, as samples, and the following results in research, was obtained. (1) A good quality of rerefinded base oil was obtained through roughly a course of developed processes of vacuum distillation process, solvent extraction process, neutralization treatment process and clay treatment process. (2) Through vacuum distillation process, the size of fine grains of insoluble colloid carbon that is, colloid carbon which was produced by burning of internal combustion engine oil and fuel, could be brought up and precipitated (3) The insoluble matters and admixtures could be easily dispersed and dissolved by mixing and extracting solvent disregarded the H$_2$SO$_4$ treatment process heretofore in use (4) waste matter heretofore called acid sludge in consequence of the process, did not appear at all. accordingly, the environmental pollution could be removed. (5) The troubles of corrosion to copper strip which was faults of the usual used oil refined products and peculiar offensive odor of the rerefined oil, could be solved through the neutralization process. (6) The yield of rerefined oil obtained through a course of processes was over 86 percent, and it is of practical use, not to speak of commercial value.

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코팅컬러의 라텍스와 회분이 코팅지의 표면강도에 미치는 영향에 관한 연구 (The Effect of a Latex and Ash Percent on the Surface Resistance of Coated Paper)

  • 전수경;한삼화;하영백;윤종태
    • 한국인쇄학회지
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    • 제22권1호
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    • pp.19-28
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    • 2004
  • A piece of coating color or base paper picked during printing is called coating pick. Loosely bonded materials of coating color or broken piece of fiber could be adhered to the blanket or would be mixed with ink during printing. Because the coating pick can make troubles in printing press such as piling, hickey and collecting, the coating pick of a paper has been one of the most serious problems in printing. In this paper, two influential factors to the coating pick in the printing, those are latex content and ash content of the coating color, are studied. The surface resistance of coating paper is directly proportional to the latex content, otherwise inversely proportional to the ash content. We propose a different way to evaluate the picking and used a homemade pick test device.

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