• Title/Summary/Keyword: Adhesive strength

Search Result 1,545, Processing Time 0.028 seconds

Sutureless Gastroduodenostomy (무봉합 위십이지장 문합술)

  • Lee, Jong-In;Kim, Jin-Young;Jeong, Jin-Ho
    • Journal of Gastric Cancer
    • /
    • v.2 no.1
    • /
    • pp.29-32
    • /
    • 2002
  • A gastroduodenostomy is the most physiological reconstruction after a distal gastrectomy. However, a gastroduodenostomy with either sutures or staples has many complications. These include bleeding, leakage and stenosis. A sutureless gastroduodenostomy with a biofragmentable anastomosis ring (BAR) in was used adenocarcinoma patients to prevent these complications from 1999. A BAR is composed of polyglycolic acid and Barium sulfate to allow for X-ray visualization. Hardy in first introduced the BAR in 1985. Since then, it has been used in an anastomosis of the colon or small bowel surgery but its use in a gastroduodenostomy is the first trial in the world. A 70 year male patient, old who received a subtotal gastrectomy (Billroth I), underwent a A sutureless gastroduodenostomy with a BAR. The gastroduodenostomy with the BAR was watertight and maintained the initial burst strength in the gastrografin X-ray study performed at the postoperative 1 week. The BAR began to fragment 3 weeks after the operation and disappeared from the digestive tract completely. The diameter of the anastomosis site was sufficient for passed foods. No other secondary changes from remained foreign bodies were found in the endoscopic examination. In a second operation to treat a primary hepatoma, there was no adhesive changes around the gastroduodenostomy site. In conclusion, a sutureless gastroduodenostomy with BAR is a safe, easy and efficient reconstructive method after a distal gastrectomy.

  • PDF

A Study on the Development of a Dry PFB Method with High Fire Resistance (고강도콘크리트 내화성능을 확보한 건식화 PFB 공법 개발에 관한 연구)

  • Kim, Woo-Jae;Jung, Sang-Jin
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2008.11a
    • /
    • pp.49-52
    • /
    • 2008
  • The present study was to develop a dry PFB method similar to the existing gypsum board construction method in order to apply the existing wet PFB method that uses fire-resistant adhesive. It was found that the existing wet method can produce concrete compressive strength of 80MPa and fire resistance of 3 hours with 30mm PF boards. The goal of development in this study was fire resistance of 3 hours through dry construction of 15mm fire-resistant boards. 1. Improved PF board was prepared by adding inorganic fiber to existing board and using aggregate with grain size of 3mm or less. Molding was done at temperature higher than that for existing PF board molding. While wet curing is used for existing PF boards, this study used dry curing in order to enhance heat insulation performance. 2. According to the results of fire resistance test, when the dry PF method was applied, the temperature of the main reinforcing bar was 116℃ in 15mm, 103.8℃ in 20mm, and 94℃ in 25mm, and these results satisfied the current standards for fire resistance control presented by the Ministry of Land, Transport and Maritime Affairs. When a 3-hour fire resistance test was performed and the external properties of the specimen were examined, the outermost gypsum board hardly remained and internal PF board maintained its form without thermal strain.

  • PDF

Debonding forces of three different customized bases of a lingual bracket system

  • Sung, Jang-Won;Kwon, Tae-Yub;Kyung, Hee-Moon
    • The korean journal of orthodontics
    • /
    • v.43 no.5
    • /
    • pp.235-241
    • /
    • 2013
  • Objective: The purpose of this study was to investigate whether extension of the custom base is necessary for enhancement of bond strength, by comparing the debonding forces and residual adhesives of 3 different lingual bracket systems. Methods: A total of 42 extracted upper premolars were randomly divided into 3 groups of 14 each for bonding with brackets having (1) a conventional limited resin custom base; (2) an extended gold alloy custom base: Incognito${TM}$; and (3) an extended resin custom base: KommonBase${TM}$. The bonding area was measured by scanning the bracket bases with a 3-dimensional digital scanner. The debonding force was measured with an Instron universal testing machine, which applied an occlusogingival shear force. Results: The mean debonding forces were 60.83 N (standard deviation [SD] 10.12), 69.29 N (SD 9.59), and 104.35 N (SD17.84) for the limited resin custom base, extended gold alloy custom base, and extended resin custom base, respectively. The debonding force observed with the extended resin custom base was significantly different from that observed with the other bases. In addition, the adhesive remnant index was significantly higher with the extended gold alloy custom base. Conclusions: All 3 custom-base lingual brackets can withstand occlusal and orthodontic forces. We conclude that effective bonding of lingual brackets can be obtained without extension of the custom base.

Effect of High Filler Loading on the Reliability of Epoxy Holding Compound for Microelectronic Packaging (반도체 패키지 봉지재용 에폭시 수지 조성물의 신뢰특성에 미치는 실리카 고충전 영향)

  • 정호용;문경식;최경세
    • Journal of the Microelectronics and Packaging Society
    • /
    • v.6 no.3
    • /
    • pp.51-63
    • /
    • 1999
  • The effects of high filler loading technique on the reliability of epoxy molding compound (EMC) as a microelectronic encapsulant was investigated. The method of high filler loading was established by the improvement of maximum packing fraction using the simplified packing model proposed by Ouchiyama, et al. With the maximum packing fraction of filler, the viscosity of EMC wart lowered and the flowability was improved. As the amount of filler in EMC increased, several properties such as internal stress and moisture absorption were improved. However, the adhesive strength with the alloy 42 leadframe decreased when the filler content was beyond the critical value. It was found that the appropriate content of filler was important to improve the reilability of EMC, and the optimum filler combination should be selected to obtain high reliable EMC filled with high volume fraction of filler.

  • PDF

Stacking Sequence Effects on Indentation Damage Behaviors of Fiber Metal Laminate (섬유의 적층 각도에 따른 섬유 금속 적층판의 압입 손상 거동)

  • Nam, H.W.;Kim, Y.H.;Jung, S.W.;Han, K.S.
    • Proceedings of the KSME Conference
    • /
    • 2001.11a
    • /
    • pp.204-209
    • /
    • 2001
  • In this research, the effects of fiber stacking sequence on damage behaviors of FML(Fiber Metal Laminates) subject to indentation loading. SOP (Singly Oriented Ply) FML and angle ply FML were fabricated to study fiber orientation effects and angle ply effects. FML were fabricated by using 1050 aluminum laminate and carbon/epoxy prepreg. To increase adhesive bonding strength, Al laminate was etched using FPL methods. The static indentation test were conducted by using UTM(5ton, Shimadzu) under the 2side clamped conditions. During the tests, load and displacement curve and crack initiation and propagation behaviors were investigated. As fiber orientation angle increases, the crack initiation load of SOP FML increases because the stiffness induced by fiber orientation is increased. The penetration load of SOP FML is influenced by the deformation tendency and boundary conditions. However, the macro-crack of angle ply FML was initiated by fiber breakage of lower ply because angle plies in Angle ply FML prevents the crack growth and consolidation. The Angle ply FML has a critical cross-angle which prevent crack growth and consolidation. Damage behavior of Angle ply FML is changed around the critical cross-angle.

  • PDF

Optimization Design of Dry Adhesion for Wall-Climbing Robot on Various Curvatures Based on Experiment (다양한 곡률에 안정적인 등반 로봇을 위한 건식 점착물질의 실험기반 설계변수 최적화)

  • Liu, Yanheng;Shin, Myeongseok;Seo, TaeWon
    • Journal of the Korean Society of Manufacturing Technology Engineers
    • /
    • v.23 no.4
    • /
    • pp.398-402
    • /
    • 2014
  • This paper presents the results of a study on the optimal footpad design for vertical climbing on acrylic surfaces with various curvatures used Taguchi methods. For a climbing robot, the adhesion system plays an important role in the climbing process. Only an appropriate adhesion strength will prevent the robot from falling and allow it to climb normally. Therefore, the footpad is a significant parameter for a climbing robot and should be studied. Taguchi methods were used to obtain a robust optimal design, where the design variables were the flat tacky elastomeric shape, area, thickness, and foam thickness of the footpad. Experiments were conducted using acrylic surfaces with various curvatures. An optimized footpad was selected based on the results of the experiments and analysis, and the stability of the wall-climbing robot was verified.

Performance evaluation of MPCM to apply for radiant floor heating system (바닥난방시스템 적용을 위한 MPCM 성능평가)

  • Jeong, Su-Gwang;Jeon, Ji-Soo;Kim, Su-Min
    • 한국태양에너지학회:학술대회논문집
    • /
    • 2012.03a
    • /
    • pp.475-479
    • /
    • 2012
  • Thermal energy storage (TES) systems using Microencapsulated phase change material (MPCM) have been recognized as one of the most advanced energy technologies in enhancing the energy efficiency and sustainability of buildings. We examined a way to incorporate MPCMs with building materials through application for wood-based flooring. Wood-based flooring is commonly used for floor finish materials of residential buildings in Korea. However, wood-based flooring has not performed the characteristic of heat storage. This study is aimed at manufacturing high thermal efficiency wood flooring by increasing its heat storage using MPCM. As a result, this study confirmed that MPCM is dispersed well in adhesive through the scanning electron microscopy analysis. From the differential scanning calorimetry analysis, it can be confirmed that this composite has the characteristic of a thermal energy storage material. Also, we analyzed how this composition was formed by physical combination through the Fourier transform infrared analysis. Also, we confirmed the bonding strength of the material by using the universal testing machine.

  • PDF

Study on the Synthesis of Polyurethane Cationomers and Their Mechanical Properties (양이온성 폴리우레탄의 합성 및 기계적 특성에 관한 연구)

  • Ann, Choun-Kee;Jin, Je-Yong;Choi, Sei-Yong
    • Elastomers and Composites
    • /
    • v.33 no.3
    • /
    • pp.177-184
    • /
    • 1998
  • Polyurethane(PU) prepolymers were synthesized from polytetramethylene ether glycol(PTMG), with 4,4'-diphenylmethane diisocyanate(MDI), toluene 2,4-diisocyanate (TDI) and isophoron diisocyanate(IPDI). After chain extention using n-methyl-diethanol amine(n-MDEA), aqueous polyurethane cationomers were prepared by addition of glycolic acid(GA) as a quaternizer. The effect of the content of chain extender and the degree of neutralization on the stability of emulsion, adhesive strength, viscosity, glass transition temperature and physical properties of emulsion cast film were investigated using UTM, viscometer and DSC.

  • PDF

Non-destructive Inspection of Semiconductor Package by Laser Speckle Interferometry (레이저 스페클 간섭법을 이용한 반도체 패키지의 비파괴검사)

  • Kim, Koung-Suk;Yang, Kwang-Young;Kang, Ki-Soo;Choi, Jung-Gu;Lee, Hang-Seo
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.25 no.2
    • /
    • pp.81-86
    • /
    • 2005
  • This paper proposes a non-destructive ESPI technique to quantitatively evaluate defects inside a semiconductor package. The inspection system consists of the ESPI system, a thermal loading system and an adiabatic chamber. The technique is high feasibility for non-destructive testing of a semiconductor and overcomes the weaknesses of previous techniques, such as time-consumption and difficult quantitative evaluation. Most defects are classified as delamination defects, resulting from the insufficient adhesive strength between layers and from non-homogeneous heat spread. Ninety percent of the tested samples had delamination defects which originated at the corner of the chip and nay be related to heat spread design.

A Fracture Mechanics Approach to Adhesively Bonded Joint Using Ultrasonic Signal Analysis (초음파 신호분석을 이용한 접착접합 이음의 파괴역학적 평가)

  • Han, Jun-Young;Oh, Seung-Kyu;Yun, Song-Nam;Lee, Won;Jang, Chul-Sup;Kim, Min-Gun;Kim, Hwan-Tae
    • Journal of Welding and Joining
    • /
    • v.21 no.5
    • /
    • pp.555-560
    • /
    • 2003
  • In automobile industry, it is necessary to reduce the weight from the view point of energy and environmental problems in these days. One of the ways for weight reduction is using adhesive aluminum structures. In this study, ultrasonic signals reflected from the adhesively bonded joint layer are used to evaluate the adhesively bonded joints. FFT is performed to determine bond-layer parameters such as effective thickness and frequency for adhesively bonded joint Al 6061 plates in comparison with the measured and theoretical ratios. And the parameters of ultrasonic wave and the J-integral are investigated to evaluate the adhesively bonded joint strength by DCB specimens.