• Title/Summary/Keyword: percentage elongation

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Study on the Synthesis of Wool-blending Fiber Bundle and New Signs of the Curve

  • Ren Yonghua;Yu Jianyong
    • Fibers and Polymers
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    • v.6 no.4
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    • pp.339-342
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    • 2005
  • In this paper, a hand-operating method (tiled test method) of the wool-blending sample is made out, and make use of the method, the test of wool-blending bundle in different blending ratio is accomplished. According to the test data, the synthesis method of the stretch curve is worked out and the synthesis software for the typical stretch curve of wool-blending bundle is designed. Through laboratory hand-operating method, the blending fasciculus applying to fiber bundle test can be obtained in a short time. Calculation for sampling is accomplished in the article. We bring up 9 new signs to describe the characteristics of the curve behind peak for the first time: elongation behind peak (HE), elongation percentage behind peak (HEP), relative elongation rate behind peak (RHE), total break work $(W_a)$, break work behind peak (HW), break work coefficient behind peak (HWC), elongation percentage of half-load behind peak (HEL), load percentage of half-elongation behind peak (HLE), break efficiency behind peak (HEC).

A Study on the Dose Distribution of Various Field and Penumbra Shield in the Telecobalt-60 (코발트-60의 조사야(照射野) 변형(變形) 및 반음영(半陰影) 차폐(遮蔽)효과에 따른 선량분포(線量分布)에 관한 연구(硏究))

  • Kim, Young-Il;Lee, Hye-Kyong
    • Journal of radiological science and technology
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    • v.8 no.2
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    • pp.71-72
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    • 1985
  • This study was performed on the dose distribution of various field size and the effect of penumbra shield in the telecobalt unit. The results obtained are as follows. 1. Errors of the light and ${\gamma}-ray$ field size was below the regulation as 0.52 percentage. 2. The coefficient of field area was increased with the larger field area, and this coefficient was showed the more difference in larger SSD. 3. The rectangular field areas, which were described by level of the same percentage depth does, were decreased with the more elongation factor. At the same elongation factor, the compensating factor was decreased with the larger field size. 4. The lead block or extension collimator was able to shield r-ray exposure of outside field size from 50 to 80 percentage. 5. On the matching adjacent fields, while the gap between beam edges are contacted, that overlapped beam edges indicated up to 140 percentage, and while the gap was 1 cm, it could be reduced to 90 Percentage. The lead-libocking on the overlapped area was more effective to lower dose, as 80 percentage in this case. 6. Percentage depth dose of various trimming field sizes were increased linearlly according to area 1 perimeter size, but the center split field size did not maintain linearlly.

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A STUDY ON THE BIOMECHANICAL PROPERTIES OF ORTHODONTIC RUBBER ELASTIC MATERIALS (교정용 고무탄성재료의 생역학적 성질에 관한 연구)

  • Song, Hyun-Sup;Kim, Sang-Cheol
    • The korean journal of orthodontics
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    • v.21 no.3
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    • pp.563-580
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    • 1991
  • The purpose of this study was to investigate and compare the biomechanical properties of orthodontic rubber elastic materials. Latex bands, nylon-covered elastic threads and polyurethane-based elastic modules, delivering $205{\pm}10$ grams force at 30mm stretching state were selected and stored separately in 3 environments-air ($22{\pm}3^{\circ}C$), distilled water ($37{\pm}1^{\circ}C$), or natural saliva ($37{\pm}1^{\circ}C$). And, the amount of remaining force and permanent elongation of each sample were measured on Instron at interval of 1 hour, 6 hours, 12 hours, 24 hours, 1 week, and 2 weeks. So the data derived were analyzed statistically. The results were as follows: 1. Force decay and permanent elongation of all materials increased with time lapsed; elastic module, latex band and nylon-covered elastic thread in that order of the amount of force decay; elastic module, elastic thread, latex band in that order of the amount of permanent elongation. 2. Among environmental conditions, force decay and permanent elongation in natural saliva, most increased, and those in air, least increased. 3. There was a negative correlation between force decay and permanent elongation. 4. Force decay and permanent elongation were most affected by the material itself, time and environments in that order. 5. After 24 hours in saliva, the percentage of remaining force in elastic module was 51.9% (107.37grams); in latex band, 83.2%(172.62grams); in elastic thread, 85.0%(179.25grams). After 2 weeks in saliva, the percentage of remaining force in elastic module was 42.9%(88.75grams); in latex band, 74.5%(154.50grams); in elastic thread, 77.6%(163.75grams).

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Effects of Restricted Oxygen, Nitric oxide, and Mercuric Chloride on the Seed Germination and Early Elongation Growth of Rice

  • Yang Woon-Ho;Kim Je-Kyu;Smucker Alvin J.M.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.51 no.4
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    • pp.287-294
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    • 2006
  • Germination and early elongation of rice after germination were investigated in anoxic air treatment, nitric oxide gas treatment, and six concentrations of mercuric chloride solutions to determine the effects of limited oxygen environment, nitric oxide, and inhibited water flux through cell membrane in $17^{\circ}C$. Anoxic air treatment affected germination of tested six varieties very little. However root elongation rates were severely inhibited while shoot growth was affected less. Reductions in shoot and root elongations demonstrated genotypic variations. Nitric oxide delayed the germination of rice even though it didn't affect the final percent germination. Elongations of root and shoot were inhibited in nitric oxide treatment. The inhibitor effect of nitric oxide on the shoot elongation of rice was less severe, while nitric oxide completely inhibited the root emergence of rice. Concentrations of $HgCl_2$ greater than $300{\mu}M$ dramatically reduced the rate and percentage of germination when compared to distilled water treatment. The reduced percent germination showed the greatest variation among rice varieties in $500{\mu}M$ solution of mercuric chloride. Ansanbyeo, Jinheung, and Odaebyeo were affected less by $HgCl_2$, Nonganbyeo and Sangmibyeo were intermediate, and the germination of Andabyeo was greatly reduced by $HgCl_2$. Root elongation of germinated rice seedlings was more sensitive to oxygen deficits, nitric oxide, and $HgCl_2$ treatments than germination and shoot elongation. In conclusion, poor seedling establishment of rice sown in flooded paddy soils, in which the oxygen supply to the seeds is restricted, appears to the result of limited root elongation rate.

A Study on the Physical Properties Change of Waterproofing Membrane Coating by Application of Modified Polymer Primer (개질 폴리머계 프라이머 적용에 따른 도막 방수재의 물리적 특성 변화 연구)

  • Lee, Jung-Hun;Cho, Hong-Bum;Jeon, Hyun-Soo;Park, Ki-Hong;Kim, Jin-Sik;Oh, Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.11a
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    • pp.191-192
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    • 2022
  • It was intended to evaluate whether the primer affects the physical performance of the waterproofing membrane coating. For this end, the physical performance change of the urethane waterproofing membrane coating was evaluated for urethane-based and polymer-based primers. As a result of the evaluation, it was confirmed that the type of primer may affect the physical performance of the waterproofing membrane coating. In particular, a difference in performance of more than 100% was confirmed in tensile strength and percentage elongation. Through these results, it was confirmed that the selection of the primer was important. In the future, follow-up studies on various waterproofing membrane coatings are needed.

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A Bioassay on Susceptivity of Selected Species to Phytotoxic Substances from Tomato Plants (토마토식물의 독성물질에 대한 타 식물의 민감도 검정)

  • 김영식
    • Journal of Plant Biology
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    • v.30 no.1
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    • pp.59-67
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    • 1987
  • To verify allelopathic effect of tomato plants a number of labovatory experiments, seed germination and seedling growth with aqueous extracts and leachates form the tomato plants, have performed. Germination percentage of the tested species was decreased by treatment with leaf, stem and root extracts as extracting time elapses. The leaf extract more inhibits the germination of the seeds than both stem and root extracts. Leachate collected from the tomato plants decreases as much as 50% of the growths in elongation as well as dry weight of seedlings of lettuce and egg plant. It is observed that with a paired-plants grown in U tube pot the tomato roots have excreted allelochemicals to inhibit the growth of the tested species and volatile substances from the tomato plants have suppressed to dry weights of lettuce, to elongation and dry weights of grapevine planted near the tomato plants.

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Characteristics of Tensile Strength and Corrosion Resistance of Lead- free Brass Containing 1 wt.% of Bi (1 wt.% Bi 함유 무연황동의 인장강도와 내식특성에 대한 연구)

  • Joo, Y.S.;Lee, S.B.;Kim, S.Y.;Joo, C.S.;Jung, B.H.
    • Journal of the Korean Society for Heat Treatment
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    • v.24 no.3
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    • pp.133-139
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    • 2011
  • This study has been investigated for tensile properties with lead-free brass containing 1 wt.% of Bi. And also characteristic of corrosion resistance was analyzed by polarization test. An increase of tempering temperature was found to tend to decrease tensile strength, and percentage of elongation was shown to be the lowest value at $300^{\circ}C$. On the other hand, the elongation was increased with an increase of tempering temperature after $300^{\circ}C$. The change of mechanical properties was closely related with the content and shape of acicular Witmanst$\ddot{a}$tten ${\alpha}$ formed at the interface of ${\beta}$ phase as well as in ${\beta}$ phase. Tensile strength had a tendency to be decreased with an increase of test temperature. The elongation was shown to be the lowest value at around $300^{\circ}C$, while it began to increase as test temperature rose after $300^{\circ}C$. It might be speculated that the reason that elongation was decreased was found to form bismuth film at the interface of ${\alpha}/{\beta}$ phase leading to be easily brittle when loaded by tensile stress. The lead-free brass containing 1 wt.% of Bi had similar characteristic of corrosion resistance with a free-cutting brass with 3.4 wt. % of Pb in spite of higher fraction of ${\beta}$ phase.

The Effect of Washing Conditions on the Dimension and Mechanical Properties of Spandex Yarns (세척조건에 스판덱스사의 길이와 기계적 성질에 미치는 영향)

  • Chung, Hae-Won;Kim, Mi-Kyung
    • Journal of the Korean Society of Clothing and Textiles
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    • v.29 no.12 s.148
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    • pp.1619-1626
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    • 2005
  • The durability of a stretch fabric is mainly related to the change in the dimension and mechanical properties of elastomeric fibers during wearing and washing. In this study, we examined the effects of washing temperature, presoaking time and the number of washing cycles on the change in length, tenacity, elongation at break, and permanent elongation after six repeated cycles of $100\%$ extension and relaxation of spandex yams with varying fineness and with a different rate of extension during heat-set. The spandex yarns continued to shrink as the wash temperature and the number of wash cycles increased. In addition, the finer spandex yams decreased in length more than the thicker yams. The increase in temperature and presoaking time tended to cause a slight decrease in the tenacity and elongation at break of the spandex yarns. Permanent elongation of the spandex yams also increased as the temperature, presoaking time and the number of washing cycles increased. Moreover, an extended presoaking time followed by washing at $40\%$ like repeated washing cycles showed the great increase in the permanent elongation of spandex yams. The thinner spandex yin had a better elasticity than the thicker one, since the former had a lower permanent elongation percentage than the latter. Based on the DSC thermograms, the melting points of the spandex yarns after washing were almost the same as those of the spandex yarns before washing.

The effect of worm cast extract on the frowth of cucumber(Cucum is sativus L.cv,H.N.Semiwhite)seedling (지렁이 분립 배출물이 오이의 초기생장에 미치는 영향)

  • 박세진;이주삼;김명원
    • Korean Journal of Organic Agriculture
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    • v.3 no.1
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    • pp.79-85
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    • 1994
  • Worm cast is one of the effective and the least harmful organic fertilizer. The purpost of this work is to elucidate the physiological role of worm cast in the plant growth. Worm cast extract contains 17.83ppm of zinc, but either cadmium or lead were not detected in it. Cucumber (Cucumis sativus L. cv. H. N. Semiwhite) was germinated and incubated with percentage-varied extract. While 10% extract stimulated sprouting of seeds, 100% extract had no effct on it. 50% extract and 100% extract enhanced hypercotyl elongation and fresh weight most effectively. Dry matter and zinc concentration in hypercotyl were increased as percentage of extract increased. Protein con-tent was not affected by extract, 100% extract inhibits water uptake of seedling. Considering these, enhancement of seedling growth was mainly based on increment of water uptake.

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Effects of Oral Taurine Supplementation on Plasma Total and Phospholipid Fatty Acid Patterns in Healthy Female Adults (타우린 복용이 정상 성인여성의 혈장 총지방산 및 인지질 지방산패턴에 미치는 영향)

  • 박태선
    • Journal of Nutrition and Health
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    • v.31 no.8
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    • pp.1315-1323
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    • 1998
  • Effect of oral taurine supplementation on plasma total and phospholidpid -fatty acid profiles and their metabolism were evaluated in healthy female adults. Among twenty five female volunteers(23.6$\pm$0.3 years old ) participated in the taruine supplementation program(6g taurine /day), twenty four subjects succesfully completed the 2 week program , and only nine subjects continued to take taurine for another 2 weeks. Levels of plasma fatty acids and taruine were measured by gas-liquid chromatobraphy and an automated amino acid analyzer based on ion exchange chromatography, respectively. Plasma taurine concentration s of the subjects were 108. 7$\pm$3.4 , 184.2$\pm$8.2 and 235.9$\pm$77.0$\mu$emol/L at 0 , 2 and 4 weeks of taurine supplementation. Fatty acid compositions and elongation and desaturation indices of polyunsaturated fatty acids (PUFA) in plasma total lipids were not influenced by oral taurine supplementation. However, fatty acid compositions and their metabolism in plasma phospholipids were significantly affected by taurine supplementation in female adults. Compared to the values for 0 week, the percentage of saturated fatty acids (SFA) in plasma phospholipid was significantly lowered at 2 weeks, but elevated at 4 weeks of taurine supplementation. In contrast , the percentage of phospholipid PUFA significantly increased at 2 weeks and decreased at 4 weeks of taurine supplementation from to the values for 0 weeks. Foru weeks of oral taurine supplementation signifinatly elevated the eongation index(20 : 4$\omega$6 ⇒22 : 4 $\omega$6, p<0.01), and decreased the desaturation index (20 : 3 $\omega$6 ⇒20 : 4 $\omega$6 , p<0.01) of $\omega$6 fatty acids in plasma phospholipids. Plasma taurine concentration was positively correlated with the percentage of 14 : 0 fatty acids and the enlongation index o f$\omega$3 fatty acids(20 : 5 $\omega$3 ⇒22 : 5 $\omega$3), and thenegatively correlated with the percentage of 20 : 0 in plasma phospholipids. These results indicate that oral taurine supplementation for 4 weeks signidicantly elelvated the percentage of SFA, and lowered the percentage of PUFA in plasma phospholipids with no influence on plasm total fatty aicd composition in healthy female adults.

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