• Title/Summary/Keyword: OH stretching

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Formation of Hydrophobic Self-assembled Monolayers on Paper Surface with Silanes (실란화 반응에 의한 종이 표면의 소수성 자기조립 단분자막 형성)

  • Oh, Min-Jeong;Lee, Hyoung;Paik, Ki-Hyon
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.42 no.1
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    • pp.64-73
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    • 2010
  • This study was conducted to modify the surface properties of papers by formation of hydrophobic self-assembled monolayer(SAM) on paper surface with silanes. A base paper I(0.5% AKD) and base paper II(1.0-1.5% AKD) were reacted with silanes(PFDTES, DMDCS, MODDCS) by immersion method and vapor deposition method. Hydrophobic SAMs(contact angle value>$120^{\circ}C$) were obtained on all papers after treatment with $10^{\mu}l$ PFDTES for 15min, with $50^{\mu}l$ DMDCS for 30min, with $50^{\mu}l$ MODDCS for 300min. When applying PFDTES to paper surface, lower silane concentration and shorter reaction time were required, whereas MODDCS with long alkyl chain required the longest reaction time of 300min. The st$\ddot{o}$ckight sizing degree of silane treated papers were increased between 105sec(base paper I) and 130sec(base paper II). The wet tensile strength of PFDTES-treated base papers(I, II) increased by 10-34% after SAM formation. However, the wet tensile strength of the DMDCS-treated base paper(I) was found to decrease from 0.067kN/m to 0.038kN/m; this may due to the cellulose degrading as a result of generated hydrogen chloride when hydroxyl group of cellulose were reacted with DMDCS. No apparent changes of PPS roughness on silane-treated papers are observed. The ATR-IR spectrum showed absorption peak located at 465 and 1200cm-1 which can be assigned to the Si-O-C asymmetric stretching and Si-O-C bonds, respectively.

Photoluminescence Characteristics of the Light-Emitting Chromophores Obtained from Organic-Inorganic Hybrid Silica Spheres

  • Park, Eun-Hye;Jeong, Chang-Gi;Kang, Kwang-Sun
    • Current Photovoltaic Research
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    • v.4 no.3
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    • pp.93-97
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    • 2016
  • Light-emitting chromophores have been separated from silica spheres modified the surface with 3-(trimethoxysilyl)propylmethacrylate (TMSPM). The photoluminescence characteristics of the chromophores were investigated with various excitation wavelengths. The TMSPM was attached to the surface of silica spheres at $75^{\circ}C$. Large number of round shaped particles of the TMSPM was on the surface of silica spheres after 3 h reaction. The TMPSM was completely covered on the surface of the spheres after 6 h reaction. The surface modified silica spheres were soaked into acetone and stored for 20 days at ambient condition. The solution color slowly changed from light yellow to deep yellow with the increase of the storing time. The FTIR absorption peaks at 3348, 2869, 2927, 1715, 1453/1377, 1296, and $1120cm^{-1}$ represent C-OH, $R-CH_3$, $R_2-CH_2$, -C=O, C-H, C=C-H, and Si-O-Si absorption, respectively. The FTIR absorption peak at $1715cm^{-1}$ representing the ester -C=O stretching vibration for silica spheres stored for 20 days was increased compared with the spheres without aging. The UV-visible absorption peaks were at 4.51 eV (275 nm) and 3.91 eV (317 nm). There were two luminescence peaks at 2.51 eV (495 nm) and 2.25 eV (550 nm). The emission at 2.51 eV was dominant peak when the excitation energy was higher than 2.58 eV, and emission at 2.25 eV became dominant peak when the excitation energy was lower than 2.58 eV.

A Comparison of Pelvic Tilt Before and After Manipulation of Sacroiliac Joint in the Patients with Low Back Pain (요통환자의 천장관절에 대한 도수교정 전과 후의 골반경사 비교)

  • Oh, Seung-Gil;Lee, Jin-Haeng
    • Journal of Korean Physical Therapy Science
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    • v.7 no.2
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    • pp.579-595
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    • 2000
  • The purposes of this study were to compare pelvic tilt before and after manipulation of sacroiliac joint in 31 low back pain patients (11 males, 20 females) with sacroiliac joint dysfunction. The sacroiliac joint of patients was manipulated on the side of anterior pelvic tilt, using the technique described by Stoddard (1962) and Greenmann (1996). I used this technique because it usually eliminated sacroiliac joint dysfunction in one treatment session. SPSS for window computer system was used to analyze the data. Also t-test was performed for comparison of pelvic tilt angle before and after manipulation, and Pearson product-moment correlation analysis was performed for intratester reliability for measurements of pelvic tilt angle before and after manipulation. The result were as follows: 1. Intratester reliability was good for measures of pelvic tilt (r=.98). 2. The pelvic tilt after manipulation was significantly decreased (mean=$3.40^{\circ}$) compared with the pelvic tilt before manipulation (p=.001). All subjects showed asymmetrical right versus left pelvic tilt before manipulation. 40% of subjects showed decreased asymmetrical right versus left pelvic tilt after manipulation, and 60% of subjects showed symmetrical right versus left pelvic tilt after manipulation. I think that pelvic tilt asymmetry with hypomobility due to loss of joint play could be symmetrized by manipulation or mobilization, but pelvic tilt asymmetry with unilateral pelvic muscle shortening could not be symmetrized by manipulation or mobilization without relaxation and stretching of shortened muscles.

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Sports-related Overuse Injuries: Elbow joint (스포츠와 연관된 과사용 증후군: 주관절)

  • Oh, Jeong-Hwan;Keum, Jung-Sup;Park, Jin-Young
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.7 no.2
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    • pp.67-74
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    • 2008
  • Repetitive overhead throwing exerts significant mechanical stress on the elbow joint. Pitching in baseball, serving in tennis, spiking in volleyball, passing in American football and launching in javelin-throwing can all produce elbow pathology by forceful valgus stress, with medial stretching, lateral compression and posterior impingement. This stress can lead to developmental anatomic changes in the young thrower. Asymptomatic pathology in the shoulder and elbow joint is prevalent and, with overuse, can progress to disabling injury. Joint injury occurs as a result of the body's inability to properly coordinate motion segments during the pitching delivery, leading to further structural damage. The implications of acute and overuse injuries and the possibility of permanent damage should be understood by parents, coaches and the athletes. Proper understanding of the intrinsic and extrinsic risk factors that could lead to elbow injuries is thus required. Measures to prevent elbow injuries should include proper coaching, warm-up, medical expertise and protective gear. Injury prevention and rehabilitation should center on optimizing pitching mechanics, core strength, scapular control, and joint range of motion.

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Influence of Alumina on Hydrothermal Synthesis of 11Å Tobermorite (알루미나가 11Å Tobermorite의 수열합성에 미치는 영향)

  • Yim Going;Yim Chai Suk
    • Korean Journal of Materials Research
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    • v.15 no.2
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    • pp.97-105
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    • 2005
  • [ $11\AA$ ] tobermorite$(5CaO{\cdot}6SiO_2{\cdot}5H_2O)$ is synthesized from the mixtures of calcium hydroride and quartz using alumina in a molar ratio $Ca(OH)_2/SiO_2$ of 0.8 at $180^{\circ}C$ for 8 and 24 hrs under saturated steam pressure. The influence of alumina on the formation of $11\AA$ tobermorite was investigated by X-ray diffraction, differential thermal analysis and infrared spectroscopy. $11\AA$ tobermorite containing increasingly larger amounts of aluminum showed a shift of the basal spacing from 11.3 to $11.6\AA$. In general, there was a direct linear relation between the basal spacing and added content of alumina. The differential thermal analysis curves showed that $11\AA$ tobermorite with increasing alumina contents exhibited the exothermic peak at high temperature, namely $11\AA$ tobermorite containing aluminum gave a sharp exothermic peak at temperature around $850\~860^{\circ}C$ in the case of $S_3\~S_5$. The absorption band at $1607\~1620cm^{-1}$ is attributed to the bending vibration of water, and the position of the main O-H stretching and Si-O lattice vibration of $11\AA$ tobermorite at 3500 and $965cm^{-1}$ respectively is not altered. Consequently the existence of alumina accelerates the crystallization of $11\AA$ tobermorite, and that the aluminum ion appears to substitute for the silicon ion in $11\AA$ tobermorite structure. Al-containing tobermorite is distinguished from Al-free tobermorite.

The Effect of the Combined Exercise Program on the Static Balance Ability of the Lumbar Instability of Adults (허리 불안정성을 가진 성인에게 적용한 복합운동프로그램이 정적균형능력에 미치는 영향)

  • Oh, Yoon-joong;Park, Jong-hang;Kim, Yoon-hwan;Kim, Tae-won
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.25 no.2
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    • pp.21-29
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    • 2019
  • Background: The purpose of this study is to investigate the effect of the combined exercise program on the static balance ability of the lumbar instability of adults. Methods: The experimental group was divided into two groups and randomly. The experimental group 1 (Exp 1) applied the combined exercise program for the lumbar stabilization exercise and strengthening exercises and the experimental group 2 (Exp 2) applied the combined exercises program for the lumbar stabilization exercises and active stretching exercises. Each experiment group performed exercise program for 4 weeks, 3 times a week, 30 minutes a day. Static balance ability was measured using GOOD BALANCE system. Results: As the comparing results of static balance ability, normal standing eye open was Ant-Post and Med-Lat showed significant differences in Exp 1 (p<.05). One leg left eye open was velocity moment showed significant differences in Exp 1 (p<.05). and one leg right eye open was Med-Lat showed significant differences in Exp 1 (p<.05). Conclusion: These results show that thoracic self mobilization is immediate effective on balance and gait ability. Thus, thoracic self mobilization will help recovery of balance and gait ability in acute stroke patients.

Cr(III)-Tetraaza Macrocyclic Complexes Containing Auxiliary Ligands (Part IV); Synthesis and Characterization of Cr(III)-Acetylacetonato, -Malonato and -Oxalato Macrocyclic Complexes

  • Byun, Jong-Chul;Han, Chung-Hun
    • Bulletin of the Korean Chemical Society
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    • v.26 no.9
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    • pp.1395-1402
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    • 2005
  • The reaction of cis-[Cr([14]-decane)$(OH)_2]^+$ ([14]-decane = rac-5,5,7,12,12,14-hexamethyl-1,4,8,11-teraazacyclotetradecane) with auxiliary ligands {$L_a$ = acetylacetonate (acac), oxalate (ox) or malonate (mal)} leads to a new cis-[Cr([14]-decane)(acac)]$(ClO_4)_2{\cdot}(1/2)H_2O\;(1),\;cis-[Cr([14]-decane)(ox)]ClO_4{\cdot}(1/2)H_2O\;(2)\;or\;cis-[Cr([14]-decane)(mal)]ClO_4{\cdot}(1/4)H_2O\;(3)$. These complexes have been characterized by a combination of elemental analysis, conductivity, IR and Vis spectroscopy, mass spectrometry, and X-ray crystallography. Analysis of the crystal structure of cis-[Cr([14]-decane)(acac)]$(ClO_4)_2{\cdot}(1/2)H_2O$ reveals that central chromium(III) has a distorted octahedral coordination environment and two acetylacetonate-oxygen atoms are bonded to the chromium(III) ion in the cis positions. The angle $N_{axial}-Cr-N_{axial}$ deviates by $11^{\circ}$ from the ideal value of $180^{\circ}$ for a perfect octahedron. The bond angle O-Cr-O between the chromium(III) ion and the two acetylacetonate-oxygen atoms is close to $90^{\circ}$. The bond lengths of Cr-O between the chromium and the acetylacetonate-oxygen atoms are 1.950(3) and 1.954(2) $\AA$. They are shorter than those between chromium and nitrogen atoms of the macrocycle. The IR spectra of 1, 2 and 3 display bands at 1560 {ν (C=O)}, 1710 {${\nu}_{as}$(OCO)} and 1660 $cm^{-1}$ {${\nu}_{as}$(OCO)} attributed to the acac, ox and mal auxiliary ligands stretching vibrations, respectively.

A Study on the Heat Resistance and Polarization Characteristics of Poly(vinyl alcohol)-I2 Complex Films Prepared with a Potassium iodide (KI를 사용하여 제조한 Poly(vinyl alcohol)-I2 착체 필름의 편광특성 및 열저항에 관한 연구)

  • Oh, Se Young;Shin, Dong Yoon
    • Applied Chemistry for Engineering
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    • v.10 no.4
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    • pp.603-607
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    • 1999
  • The polarization characteristics of poly(vinyl alcohol)-iodine complex, (PVA-KI system) prepared by the oxidation process of PVA film containing a potassium iodide (KI) were investigated. The UV-visible spectrum of the PVA-KI system polarizing film showed avsorption bands corresponding to $I^{-}$, $I{_3}{^-}$ and $I{_5}{^-}$ chromophoric species at 220 nm, 290~360 nm, respectively. The polarization efficiency and transmittance of PVA-KI system film were significantly influenced by oxidation time, stretching ratio and concentration of KI. The prepared polarizing film exhibited a high polarization efficiency(99.5%) and transmittance(45%). Especially, the heat resistance of the polarizing film was higher than that of a commercial PVA-$I_2$ polarizing film. It may be argued that the result should come from a difference in oxidation process of PVA polarizing film.

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Comparative Analysis from Perspective of Kinesiology between Korean Athletes and Gold and Bronze Medalists in Glide-Type Shot Put at Daegu World Athletic Championships in 2011 (2011 대구세계육상선수권대회 Gilde Type 포환던지기 한국선수와 결승 1, 3위 선수와의 운동학적 비교분석)

  • Oh, Chow-Hwan;Choi, Su-Nam;Shin, Eui-Su;Lee, Jeong-Tae;Jeong, Ik-Su;Bae, Jae-Hee;Park, Seung-Bum
    • Korean Journal of Applied Biomechanics
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    • v.21 no.5
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    • pp.645-652
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    • 2011
  • The purpose of this study was to analyze, in real time, the glide motion and release motion of domestic athletes and gold and bronze medalists employing the glide technique for the men's shot put at the Daegu World Athletic Championship in 2011. In the glide motion, the Korean athletes had a relatively high body center and shot put heights and lager stretching angles for their hips and knees. In the delivery phase, which shifts to the release phase, the Korean athletes showed slower vertical body center and shot put speeds, and they changed the phase, to the release phase by using a small body angle. In the release phase, the Korean athletes showed differences in their projection speeds and vertical body center speeds. The world-famous players showed high angle speeds, which refer to the composition of the rotation force at the moment of release (body, hip, and shoulder line). In the release phase, the Korean athletes did not have fully stretched hip and knee angles, which might have negatively influenced the vertical speed. Because the Korean athletes showed relatively low projection heights and projection angles. it was found that they need to enhance the muscular power of their, throwing arms and lower limbs.

Development of an Exercise Program for Postmastectomy Patient (유방절제술 환자를 위한 운동프로그램 개발)

  • Lee, Ja-Hyung;Cho, Jae-Kyung;Oh, Ji-Na;Kim, Sung-Hee;Ahn, Hye-Im
    • Women's Health Nursing
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    • v.10 no.4
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    • pp.301-310
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    • 2004
  • Purpose: The purpose of this study was to develop an exercise program for postmastectomy patients. Method: This study was conducted from October, 2003 to June, 2004. The exercise program was developed based on literature review and needs assessment using focus group interviews. The subjects for the focus group interview consisted of 11 patients, 13 recovering patients, and 20 nurses from 3 hospitals. Development of the program was proceeded with analysusm design and development steps. Result: The results of the needs assessment using the focus group interview showed that the exercise program was imperative for postmastectomy patients. Based on the results, a home video tape containing 3 steps, was developed. Each step includes warming-up, stretching, the main exercise, and cool-down. Steps 2 and 3 include exercises with an elastic band, and an elastic ball. The program was modified after conducting a pre-test. A self-checklist including shoulder mobility, hand strength, arm volume and subjective comments on how they feel will be used before and after the exercise program. Conclusion: The exercise program will improve breast cancer patients' quality of life and their physical well-being. Further studies are recommended to test the effectiveness of the exercise program.

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