• Title/Summary/Keyword: 치수 안전성

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Investigating the Partial Substitution of Chicken Feather for Wood Fiber in the Production of Wood-based Fiberboard (목질 섬유판 제조에 있어 도계부산물인 닭털의 목섬유 부분적 대체화 탐색)

  • Yang, In;Park, Dae-Hak;Choi, Won-Sil;Oh, Sei Chang;Ahn, Dong-uk;Han, Gyu-Seong;Oh, Seung Won
    • Korean Chemical Engineering Research
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    • v.56 no.4
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    • pp.577-584
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    • 2018
  • This study was conducted to investigate the potential of chicken feather (CF), which is a by-product in poultry industry, as a partial substitute of wood fiber in the production of wood-based fiberboard. Keratin-type protein constituted the majority of CF, and its appearance did not differ from that of wood fiber. When the formaldehyde (HCHO) adsorptivities of CF compared by its pretreatment type, feather meal (FM), which was pretreated CF with high temperature and pressure and then grounded, showed the highest HCHO adsorptivity. In addition, there was no difference between the adsorbed HCHO amounts, which was measured by dinitrophenylhydrazine method, of scissors-chopped CF and CF beated with an electrical blender. Mechanical properties and HCHO emission of medium-density fiberboards (MDF), which were fabricated with wood fiber and 5 wt% CF, beated CF or FM based on the oven-dried weight of wood fiber, were not influenced by the pretreatment type of CF. However, when the values compared with those of MDF made with just wood fiber, thickness swelling and HCHO emission of the MDF were improved greatly with the addition of CF, beated CF or FM. Based on the results, it might be possible to produce MDF with improved dimensional stability and low HCHO emission if CF, beated CF or FM is added partially as a substitute of wood fiber in the manufacturing process of MDF produced with the conventional urea-formaldehyde resin of $E_1$ grade. However, the use of CF or FM in the production of MDF has a low economic feasibility at the current situation due to the securing difficulty and high cost of CF. In order to enhance the economic feasibility, it requires to use CF produced at small to medium-sized chicken meat plants. More importantly, it is considered that the technology developed from this research has a great potential to make provision for the prohibition of animal-based feed and to dispose environmentally avian influenza-infected poultry.

Suprapubic Bladder Aspiration Assisted by Ultrasound (초음파 보조하에 시행한 치골상부 방광천자의 유용성)

  • Lee Jung Won;Park Soeun;Cho Su Jin;Yoo Eun Sun;Kim Hae Soon;Lee Seoung Joo
    • Childhood Kidney Diseases
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    • v.6 no.1
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    • pp.68-74
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    • 2002
  • Purpose: Suprapubic bladder aspiration(SBA) of urine is the most reliable method to obtain urine avoiding contamination in non-toilet trained infants. Ultrasonography is a useful tool for guiding the anatomic location as well as for direct visualization during procedure. We evaluated the success rate and complication of ultrasound(US) assisted SBA Methods. Sixty infants who visited Ewha Womans University Mokdong Hospital, with suspected urinary tract infection were randomly divided into the US assisted (n=32) and blind SBA(control, n=28) group. In US assisted SBA group, the anteroposterior(AP), transverse, and sagittal diameters and the volume of the bladder were measured. In the blind SBA group, urine was blindly aspirated when the urinary bladder was palpated at the suprapubic area. The rate of successful urine aspiration, the number of attempts until successful aspiration, aspirated urine volume were compared between the two groups. Results: The success rate was $100\%$(32/32) in the US assisted group, which was significantly higher than $85.7\%$(24/28) of the control group (P<0.05). The aspirated urine volume in the US assisted group was $7.4{\pm}3.7\;mL$, which was significantly higher than $4.5{\pm}3.4\;mL$ of the control group (P<0.05), The diameters and volume of bladder in successful aspiration were $2.1{\pm}0.7\;cm$ in AP diameter, $3.1{\pm}0.6\;cm$ in transverse diameter, $4.2{\pm}1.0\;cm$ in sagittal diameter and $15.2{\pm}10.4\;mL$ in volume, which were significantly higher than those ($1.7{\pm}0.3\;cm,\;1.7{\pm}0.3\;cm,\;1.8{\pm}0.7\;cm,\;2.4{\pm]0.6\;cm,\;3.9{\pm}2.5$) of the control group (P<0.05) The correlations between the AP(r=0.78), transverse (r=0.72), sagittal(r=0.91) diameter and bladder volume were significant (P<0.05). SBA was $100\%$ successful in the AP diameter >3 cm, transverse diameter >4 cm, depth >4 cm and bladder volume >5 mL. Conclusion: US assistance can significantly improve the success rate of SBA in infant with suspected urinary tract infection. (J Korean Soc Pediatr Nephrol 2002 ; 6 : 68-74)

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Nondestructive Examination of PHWR Pressure Tube Using Eddy Current Technique (와전류검사 기술을 적용한 가압중수로 원전 압력관 비파괴검사)

  • Lee, Hee-Jong;Choi, Sung-Nam;Cho, Chan-Hee;Yoo, Hyun-Joo;Moon, Gyoon-Young
    • Journal of the Korean Society for Nondestructive Testing
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    • v.34 no.3
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    • pp.254-259
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    • 2014
  • A pressurized heavy water reactor (PHWR) core has 380 fuel channels contained and supported by a horizontal cylindrical vessel known as the calandria, whereas a pressurized water reactor (PWR) has only a single reactor vessel. The pressure tube, which is a pressure-retaining component, has a 103.4 mm inside diameter ${\times}$ 4.19 mm wall thickness, and is 6.36 m long, made of a zirconium alloy (Zr-2.5 wt% Nb). This provides support for the fuel while transporting the $D_2O$ heat-transfer fluid. The simple tubular geometry invites highly automated inspection, and good approach for all inspection. Similar to all nuclear heat-transfer pressure boundaries, the PHWR pressure tube requires a rigorous, periodic inspection to assess the reactor integrity in accordance with the Korea Nuclear Safety Committee law. Volumetric-based nondestructive evaluation (NDE) techniques utilizing ultrasonic and eddy current testing have been adopted for use in the periodic inspection of the fuel channel. The eddy current testing, as a supplemental NDE method to ultrasonic testing, is used to confirm the flaws primarily detected through ultrasonic testing, however, eddy current testing offers a significant advantage in that its ability to detect surface flaws is superior to that of ultrasonic testing. In this paper, effectiveness of flaw detection and the depth sizing capability by eddy current testing for the inside surface of a pressure tube, will be introduced. As a result of this examination, the ET technique is found to be useful only as a detection technique for defects because it can detect fine defects on the surface with high resolution. However, the ET technique is not recommended for use as a depth sizing method because it has a large degree of error for depth sizing.