• Title/Summary/Keyword: activation volume

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A comparison of vital capacity values and respiratory muscles activities on pelvic tilt position

  • Jang, Seo-Young;Lee, Su-Young
    • Physical Therapy Rehabilitation Science
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    • v.4 no.2
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    • pp.108-114
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    • 2015
  • Objective: The purpose of this study was to examine the effect on vital capacity (VC) and inspiratory muscle activation according to the anterior and posterior pelvic tilt positions. Design: One group pretest-posttest design. Methods: Twenty-six healthy adult men and women, age 19 to 27 years, volunteered to participate in this study. Forced vital capacity (FVC), and forced expiratory volume in 1 second ($FEV_1$) were measured by desktop spirometer in the pelvic positions during respiration, and muscle activation was recorded from sternocleidomastoid, upper trapezius, external intercostal, rectus abdominis, and external oblique muscles by surface electromyography (EMG) at the same time. EMG values were normalized by maximum muscle contractions (% maximum voluntary isometric contraction). Subjects were to breathe in as much air as possible and then exhale as quickly as possible in both anterior and posterior pelvic tilt positions. To measure lung capacity, inspiration was measured for 5 seconds and expiration was measured for 7 seconds with data collection taken place during the middle three seconds. Lung capacities were measured in each position three times. Results: For the results of this study, there was a significant increase in both FVC and $FEV_1$ values during the anterior pelvic tilting compared to the posterior pelvic tilting posture (p<0.05). The sternocleidomastoid, upper trapezius muscle, rectus abdominus and external oblique muscle activation was significantly increased during anterior pelvic tilt compared to the posterior pelvic tilt position (p<0.05). Conclusions: These findings suggest that pelvic anterior tilt position could be more effective for vital capacity and respiratory muscles activation during respiration.

Kinetics of Acid Hydrolysis of trans-Fluoroaquobis(ethylenediamine) Chromate(III) Cation (trans-Fluoroaquobis(ethylendiamine) Chromate(III) Cation 수화반응 속도에 대한 온도와 압력의 영향)

  • Oh Sang-Oh;Lee Sang-Hyup;Lim Jong-Wan
    • Journal of the Korean Chemical Society
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    • v.30 no.3
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    • pp.307-311
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    • 1986
  • The rates of hydrolysis of the complex, $trans^-[Cr(en)_2F(H_2O)]^{2+}$, have been investigated using spectrophotometric method at various temperatures and pressure. Temperature was 30${\circ}C$ to 50${\circ}C$ and pressure was varied up to 1500bar. The rate constant measured at 30${\circ}C$ is $2.632{\times}10^{-5}sec^{-1}$. The rate constants are decrease with increasing pressure at constants temperature. Activation volume and other activation parameters are calculated from these rate constants. The activation volumes are all positive and lie in the limited range 0.447 ∼ 3.152$cm^3$/mol and the activation entropies are small values. From the results, it was found that this reaction was endothermic and enthalphy controlled reaction in the experimental temperature.

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Different Levels of Platelet Activation in Normal Pregnancy and Pregnancy-induced Hypertension (PIH)

  • Jo, Yoon-Kyung;Im, Jee-Aee;Eom, Yong-Bin;Suh, Sang-Hoon
    • Biomedical Science Letters
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    • v.13 no.1
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    • pp.11-15
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    • 2007
  • We examined the effects of pregnancy and pregnancy-induced hypertension (PIH) on platelet activation. Thirty-six women with PIH (blood pressure > 140/90 mm Hg after two consecutive measurements after the $24^{th}$ weeks of gestation) without proteinuria, fifty-six normotensive pregnant women, and fifty non-pregnant women were studied. WBC, RBC, platelet related variables, including mean platelet component (MPC), mean platelet volume (MPV) and platelet component distribution width (PCDW) were determined for this study. MPC levels were significantly lower in women with PIH compared with normotensive pregnant women and non-pregnant women (P<0.05). MPC levels were inversely con-elated with PIH (r=-0.49, P<0.001), systolic BP (r=-0.22, P<0.01), diastolic BP (r=-0.17, P<0.005), WBC (r=-0.30, P<0.001), MPV (r=-0.41, P<0.001), and PCDW (r=-0.68, P<0.001), and positively con-elated with RBC (r=0.32, P<0.001), platelet count (r=0.21, P<0.05), and mean platelet mass (MPM) (r=0.18, P<0.05). MPC levels were found to be an independent factor associated with PIH and PCDW (P<0.01) after adjustments were made for potential confounding factors such as gestational age, systolic blood pressure, diastolic blood pressure, WBC, RBC, Platelet count, and PCDW. In conclusion, MPC levels were significantly lower in women with PIH, and MPC levels were found to be an independent factor associated with PIH and PCDW. Therefore, platelet activation is suggested as a useful predictor for patients with PIH.

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Evaluation of Genotoxicity of CP Pharmacopuncture Using an In Vitro Chromosome Aberration Test in Chinese Hamster Lung Cell (Chinese Hamster Lung 세포를 이용한 염색체이상 시험을 이용한 CP약침의 유전독성평가)

  • Hwang, Ji Hye;Jung, Chul;Ku, Jaseung
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.34 no.6
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    • pp.355-361
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    • 2020
  • This study was designed to assess the toxicity of capsaicin-containing (CP) pharmacopunture using an in vitro chromosomal aberrations in Chinese hamster lung (CHL/IU) cells. In order to determine the high dose level in the main study of this study, a dose range finding study was conducted first. The high dose was selected at 10.0% of CP pharmacopuncture extract, and then diluted sequentially to produce lower dose levels of 5.00, 2.50, 1.25, 0.625 and 0.313% by applying a geometric ratio of 2. As a result, the cytotoxicity and precipitation of the CP pharmacopuncture as a test substance were not evident at any dose level during short-time treatment with and without metabolic activation and continuous treatment without metabolic activation. Therefore, the dose levels for this study were chosen as 10.0, 5.0, and 2.5%., and the treatment volume was 1.3 mL. In addition, negative and positive controls were set. In main study, the frequency of cells with chromosome aberrations in CP treated groups was less than 5% in short-time treatment with and without metabolic activation and continuous treatment without metabolic activation. In addition, there was no statistically significant difference when compared to the negative control group. The frequency of cells with structural chromosomal aberrations in the positive control group was more than 10% compared to the negative control group, and it increased statistically significantly. In conclusion, under the conditions of this study, CP pharmacopuncture did not show the possibility of causing chromosome aberrations.

Production and CO2 Adsorption Characteristics of Activated Carbon from Bamboo by CO2 Activation Method (CO2 활성화법에 의한 대나무 활성탄 제조와 CO2 흡착 특성)

  • Bak, Young-Cheol;Cho, Kwang-Ju;Choi, Joo-Hong
    • Korean Chemical Engineering Research
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    • v.43 no.1
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    • pp.146-152
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    • 2005
  • The activated carbon was produced from Sancheong bamboo by carbon dioxide gas activation methods. The carbonization of raw material was conducted at $900^{\circ}C$, and $CO_2$ activation reactions were conducted under various conditions: activation temperatures of $750-900^{\circ}C$, flow rates of carbon dioxide $5-30cm^3/g-char{\cdot}min$, and activation time of 2-5 h. The yield, adsorption capacity of iodine and methylene blue, specific surface area and pore size distribution of the prepared activated carbons were measured. The adsorption capacity of iodine (680.8-1450.1 mg/g) and methylene blue (23.5-220 mg/g) increased with increasing activation temperature and activation time. The adsorption capacity of iodine and methylene blue increased with the $CO_2$ gas quantity in the range of $5-18.9cm^3/g-char{\cdot}min$. But those decreased over those range due to the pore shrinkage. The specific volume of the mesopore and macropore of bamboo activated carbon were $0.65-0.91cm^3/g$. Because of this large specific volume, it can be used to the biological activated carbon process. Bamboo activated carbon phisically adsorbed the $CO_2$ of maximum 106 mg/g-A.C in the condition of 90% $CO_2$ and adsorption temperature of $20^{\circ}C$. The $CO_2$ adsorption ability of bamboo activated carbon was not changed in the 5 cyclic test of desorption and adsorption.

Preparation and Characterization of High Performance Activated Carbon Fibers from Stabilized PAN fibers (PAN계 안정화섬유로부터 고기능성 활성탄소섬유의 제조 및 특성)

  • 임연수;유기상;문숙영;정윤중;김명수;함현식
    • Journal of the Korean Ceramic Society
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    • v.40 no.5
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    • pp.468-474
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    • 2003
  • Activated carbon fibers were prepared from stabilized PAN fibers by physical and chemical activation to compare their characteristics. In this study, stabilized PAN fibers were activated by physical activation with steam and CO$_2$, and by chemical activation with KOH. The fabricated activated carbon fibers were evaluated and compared such as specific surface area, pore size distribution, pore volume, and amount of iodine adsorption. In the steam activation, a specific surface area of 1635 m$^2$/g was obtained after heat treatment at 990$^{\circ}C$. Otherwise, in the CO$_2$ activation, produced activated carbon fibers had been a specific surface area of 671 m$^2$/g after heat treatment at 990$^{\circ}C$. In chemical activation using KOH, a specific surface area of 3179 m$^2$/g was obtained with a KOH/ stabilized PAN fiber ratio of 1.5 : 1 at 900$^{\circ}C$. Nitrogen adsorption isotherms for fabricated activated carbon fibers showed type I and transformation from type I and II in the Brunauer-Deming-Deming-Teller (B.D.D.T) classification. Increasing specific surface area Increased the amount of iodine adsorption in both activation methods. Because the ionic radius of iodine was smaller than the interior micropore size of activated carbon fibers.

Influence of Activation Temperature on Surface and Adsorption Properties of PAN-based Activated Carbon Fibers/Phenolic Resin Matrix Composites (활성화 온도에 의한 PAN계 활성탄소섬유/페놀수지 복합재료의 표면 및 흡착특성)

  • 박수진;김기동;이재락
    • Polymer(Korea)
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    • v.24 no.1
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    • pp.97-104
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    • 2000
  • PAN-based activated carbon fibers/phenolic resin matrix composites (ACFCs) were manufactured via molding process with oxidized carbon fabrics (plain-type) and phenolic resin (resole-type) compounded by 70 : 30 wt%. The green body (as molded) was submitted to carbonization (at 100$0^{\circ}C$) in an inert environment and activation (at 700, 800, 900 and 100$0^{\circ}C$) in a $CO_2$ environment. In this work, the influence of activation temperatures was investigated in surface properties, such as pH, acid- and base-values by titration method, and in adsorption properties, i.e., specific surface area and pore structures by BET-method of the composites. Also, the pressure drops of the specimens were calibrated by ASTM. As a result, the activation temperature influenced the surface property of ACFCs. When the activation temperature was higher than 90$0^{\circ}C$, the surface was gradually developed in basic nature. And, the evolutions of specific surface area, total pore volume and pore size distribution of ACFCs could be easily confirmed the dependence on the activation temperature. Among them, well-developed pore structure from adsorption characteristics was changed of the ACFCs activated at 90$0^{\circ}C$. Also, the pressure drop was slightly decreased with increasing the temperature due to increasing the burn-off with heat treatment temperature of ACFCs.

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Preparation of Glass-Ceramics in $Li_2O-Al_2O_3-TiO_2-SiO_2$ System by Sol-Gel Technique : (I) Preparation of Porous Monolithic Gel in $Li_2O-Al_2O_3-TiO_2-SiO_2$ System by Sol-Gel Method (Sol-Gel법에 의한 $Li_2O-Al_2O_3-TiO_2-SiO_2$계 다공성 결정화 유리의 제조 : (I) Sol-Gel 방법에 의한 $Li_2O-Al_2O_3-TiO_2-SiO_2$계 다공성 겔체의 제조)

  • 조훈성;양중식;권창오;이현호
    • Journal of the Korean Ceramic Society
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    • v.30 no.7
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    • pp.535-542
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    • 1993
  • It was investigated in this study that a preparation method, activation energy, surface area, pore volume, pore size distribution and DTA analysis of the dry gel in process of producing monolithic porous gel in Li2O-Al2O3-TiO2-SiO2 system by the sol-gel technique using metal alkoxides. Activation energy for gellation according to the variation of water concentration and the kind of catalysts ranged from 10 to 20kcal/mole. Monolithic dry gels were prepared after drying at 9$0^{\circ}C$ when the amount of water for gellation was 4~8 times more than the stoichiometric amount, that was necessary for the full hydrolysis of the mixed metal alkoxide. The specific surface area, the pore volume, the average pore radius of the dried gel at 18$0^{\circ}C$ according to the various kinds of catalyst were about 348~734$m^2$/g, 0.35~0.70ml/g and 10~35$\AA$, respectively. It showed that the dry gels were porous body. As a result ofthe analysis of DTA, it was confirmed that the exothermaic peaks at 715$^{\circ}C$ and 77$0^{\circ}C$ was clue to the crystallization of dried gel.

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Filler-Elastomer Interactions. 2. Cure Behaviors and Mechanical Interfacial Properties of Carbon Black/Rubber Composites (충전재-탄성체 상호작용. 2. 카본블랙/고무 복합재료의 경화 거동 및 기계적 계면 물성)

  • Kim, Jeong-Soon;Park, Soo-Jin
    • Elastomers and Composites
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    • v.35 no.2
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    • pp.122-131
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    • 2000
  • In this work, the effect of chemical surface treatments on morphology of carbon blacks was investigated in terms of cure behavior and tearing energy ($G_T$) of carbon blacks/rubber composites. As experimental results, the polar or nonpolar chemical treatment led to a significant physical change of carbon black morphology. The cure activation energies (Ea) and frequency factor (A) obtained from Kissinger equation decreased with improving the dispersion of carbon flacks, resulting in high reactivity. However, a significant advantage of carbon black/rubber composites is gained by carbon blacks treated in basic (BCB) or nonpolar (NCB) chemical solution, resulting in increasing the tearing energy. These results could be explained by changes of dispersion, agglomerate, surface functional group, void volume, and cross-linking density of carbon black/rubber composites.

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The Influence of Temperature and Strain Rate on the Mechanical Behavior in Uranium

  • Lee, Key-Soon;Park, Won-Koo
    • Nuclear Engineering and Technology
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    • v.10 no.2
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    • pp.73-78
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    • 1978
  • The effect of temperature and strain rate on the deformation behavior of $\alpha$-uranium was investigated in the temperature ranged 300$^{\circ}$ to 55$0^{\circ}C$ by strain, rate change test. Strain rate sensitivity, activation volume, strain rate sensitivity exponent and dislocation velocity exponent were determined. The strain rate sensitivity exponent and dislocation velocity exponent were determined. The strain rate sensitivity exponent increases with strain below 40$0^{\circ}C$, while the exponent decreases with strain above 50$0^{\circ}C$. It is believed that the increase of strain rate sensitivity exponent with strain below 40$0^{\circ}C$ can be attributed to an increase in internal stress as a result of work hardening while decrease of the exponent with strain above 50$0^{\circ}C$ is due to predominance of thermal softening over work hardening because more slip, system are active in deformation above about 50$0^{\circ}C$.

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