• 제목/요약/키워드: $({\alpha}-phase$

검색결과 1,601건 처리시간 0.031초

${29}^Si$ MAS NMR Study on Quantitative Analysis of the Amorphous Phase in a $Si_3N_4$ Powder

  • Fujimori, Hirotaka;Kitahara, Hiromoto;Ioku, Koji;Goto, Seishi;Nakayasu, Tetsuo;Yamada, Tetsuo
    • The Korean Journal of Ceramics
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    • 제6권2호
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    • pp.155-158
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    • 2000
  • NMR study has been used for measuring precise quantity of the amorphous phase in the $Si_3N_4$powder. Care must be taken to allow the $^{29}$Si nuclear spin system to fully relax between pulses in order to make the signals proportional to the number of nuclei in each phase. $^{29}$Si MAS spectrum was decomposed into the three spectra of $\alpha$-, $\beta$-, and amorphous $Si_3N_4$assuming pseudo-Voigt function. Moreover, the Rietveld analysis of the powder X-ray diffraction data was performed to measure quantity of crystalline phases as $\alpha/\beta$ ratio.

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ON MEASURING THE WELDING TEMPERATURE OF CONNECTOR

  • Deng Jyh-jeng
    • 한국품질경영학회:학술대회논문집
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    • 한국품질경영학회 1998년도 The 12th Asia Quality Management Symposium* Total Quality Management for Restoring Competitiveness
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    • pp.361-377
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    • 1998
  • The measurement of welding temperature of connector is usually performed with an infra red temperature gauge. However, the factors, which influence the temperature measurement, are rarely known. This research used the welding temperature measurement of the connector as an example, applying the experimental design, in two-phase experiments, to search the affecting factors. In phase-I experiment, we used a resolution III, seven-factor fractional factorial design with two levels for each factor. The result showed that none of the factor was significant in affecting the welding temperature when the type I error ${\alpha}$ was 0.05. Next, we did the phase-II factorial experiment with three factors and each factor had three levels. The experiment showed the experimental time was significant in affecting the temperature measurement when the type I error ${\alpha}$ was 0.05. Further Duncan's multiple range tests on the second experimental data showed that the later the experimental time, the weaker the light intensity could have on the temperature measurement and the average of the highest temperatures was lower. Moreover, the later the experimental time, the smaller was the variance of the temperature measurement and the difference between the averages of the highest and the lowest temperatures was also lower.

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간호조직문화 측정도구 개발을 위한 연구 (The Development of the Nursing Organization Culture Measurement tool)

  • 김문실;김지현;한수정
    • 간호행정학회지
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    • 제10권2호
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    • pp.175-184
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    • 2004
  • Purpose: The purpose of this study was to develop a nursing organization culture measurement tool and to test the validity and reliability of the tool. Method: This study conducted in three phases. In phase 1, theoretical framework choice, Phase 2, measurement items selection, Phase 3, testing of validity and reliability. In order to test validity and reliability of the measurement, data were collected from 915 nurses, working in the 22 hospitals with more 500 beds. The data obtatined were analyzed by SPSS-Win 10.0 program using percentages, Factor Analysis, Cronbach's alpha Coefficients. Result: As a result of the study, nursing organization culture measurement scale was consisted of 20 items, 4 factors. 4 factor explained 60.54% of the total variance, and the Cronbach's alpha of this scale was .8829. Conclusions: The Study supports the validity and reliability of the scales. Therefore, this scale can be effectively utilized for the evaluation of nursing organization culture in hospital setting.

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A Study of Solar Eruption : The Case of 2011 Sep. 29 Event

  • Cho, Kyuhyoun;Chae, Jongchul;Ahn, Kwangsu
    • 천문학회보
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    • 제38권2호
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    • pp.90.2-90.2
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    • 2013
  • Filament eruptions are one of the energetic phenomena on the solar surface with flares and coronal mass ejections (CMEs). We observed the whole process of filament eruption that occurred in AR 11305 in association with a C5.6 flare on 2011 September 29th using the Fast Imaging Solar Spectrograph (FISS) and the Solar Dynamics Observatory (SDO). The eruption consists of a slow phase with a transverse speed of ~10 km $s^{-1}$ in 16 minutes and a fast phase with a transverse speed of ~200 km $s^{-1}$ in 3 minutes. Near the beginning of slow phase eruption, preflare brightening occurred beneath the filament in $H{\alpha}$ and some EUV images. The preflare brightening region is associated with a blue-shifted $H{\alpha}$ feature with a speed of ~60 km $s^{-1}$. It appears that this is the outflow from magnetic reconnection which may have occurred at relatively low atmosphere. Our result support the notion that the preflare brightening is a process of magnetic reconnection playing an important role in triggering the filament eruption by deformative the magnetic field lines under the eruptive filament.

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Promoting Effect of a Mixture of 8 Herbal Extracts (SPELA 707) on Hair Growth

  • Choi, Eun-Young;Park, Soo-Nam;Park, Sung-Uk;Choi, Seong-Won;Ro, Byung-In;Chung, Myung-Hee
    • The Korean Journal of Physiology and Pharmacology
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    • 제7권2호
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    • pp.91-96
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    • 2003
  • In Korean folk medicine, several herbs, Glycyrrhizae Radix, Persicae Semen, Salviae Radix, Angelicae Gigantis Radix, Zanthoxyli Fructus, Ginseng Radix Alba, Cnidii Rhizoma, and Carthami Flos, are known to enhance blood circulation and have wound healing or anti-inflammatory effects. These pharmacological actions prompted us to investigate whether these herbs might stimulate hair growth. Thus, using a mixture of their extracts called SPELA 707, we investigated their effects and found that SPELA 707 possessed significant hair cycle converting activity from the telogen phase to the anagen phase in C3H mice. Furthermore, we found that SPELA 707 enhanced the hair density in subjects with hair loss and also promoted the conversion of hair into the anagen phase in subjects with androgenetic alopecia. In addition, hair growth promotion effect of SPELA 707 occurred through inhibition of steroid $5{\alpha}$-reductase activity, which is known to block hair growth. Taken together, these results suggest that SPELA 707 has a potential to be used for the treatment of hair loss.

과포정계 합금의 응고조직에 미치는 대류의 영향 (Effect of Convection on the Solidification Microstructure of Hyper-Peritectic Systems)

  • 박병규;김무근;박장식;김근오;최재광
    • 대한기계학회논문집B
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    • 제25권7호
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    • pp.958-966
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    • 2001
  • This study has examined the microstructural development in the Bridgman type directional solidification of hyper-peritectic Sn-Cd alloys, and the temperature and flow field have been numerically simulated to see if there is any change induced by convection. The directional solidification experiments carried out in quartz tubes with inside diameters of 0.4∼6mm showed that the resulting microstructures are clearly dependent on the size of tube diameters. The bigger ampoules where the effect of convection is highly expected produced saw-like structures resulting from the primary $\alpha$ and peritectic $\beta$ phase growing together at a planar solid-liquid front, with the former being surrounded by the latter. In the smaller ampoules, where the effect of convection is expected low however, the saw structure disappears, and as is understood from the theoretical prediction based on diffusion-controlled solidification the initial growth of the primary $\alpha$ phase is replaced by the nucleation of the peritectic $\beta$ phase whose growth continues to the end of the solidification.

Microstructure and Magnetic Properties of Nanocomposite Sm2Fe15Ga2Cx/α-Fe Permanent Magnets

  • Cheng, Zhao-hua
    • Journal of Magnetics
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    • 제8권1호
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    • pp.18-23
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    • 2003
  • In our previous work, microstructure and magnetic properties of two-phase exchange-coupled $Sm_2Fe_{15}Ga_2C_{x}$/$\alpha$-Fe nanocomposites have been investigated by means of x-ray diffraction, transmission electron microscopy and magnetization measurement. It was found the exchange coupling between the magnetically hard phase $Sm_2Fe_{15}Ga_2C_{x}$ and the magnetically soft one ${\alpha}$-Fe results in an enhancement of the remanence. The sizes of crystallites of both phases are, however much larger than the Block domain-wall width of the magnetically hard phase. This microstructure gives rise to a concave demagnetization curve and consequently reduces the maximum energy Product. In order to improve their magnetic properties, a few Percent of Zr, which may be effective to refine the microstructure through rapid quenching, was introduced into the nanocomposites. The addition of Zr was found to improve the magnetic properties significantly, Under optimum heat-treatment conditions, the remanence, coercivity and maximum energy Product increase from 0.65 T, 0.48 T and 50 kJ/$m^{3}$ for the Zr-free sample to 0.72 T, 0.77 T and 71.6 kJ/$m^{3}$ for the 1 at.% Zr-containing one, respectively, The improvements of magnetic properties are due to the refinement of microstructure by the addition of Zr.

영성 측정도구 개발과 평가 (Development and Validation of the New Version of Spirituality Assessment Scale)

  • 고일선;최소영;김진숙
    • 대한간호학회지
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    • 제50권1호
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    • pp.132-146
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    • 2020
  • Purpose: The purpose of this study was to develop a new version of Spirituality Assessment Scale (N-SAS) and verify its reliability and validity. Methods: The total of 59 preliminary items for the N-SAS were selected through a literature review, two rounds of experts' content validation, cognitive interviews, and pre-tests. Verification of its reliability and validity was divided into two phases. In Phase I, questionnaires were collected from 219 adults. Reliability was tested using Cronbach's alpha, validity with item analysis, and exploratory factor analysis. In Phase II, questionnaires developed based on the results of Phase I were collected from 225 adults. Reliability was tested using Cronbach's alpha, validity with confirmatory factor analysis, and criterion validity. Results: The final version of the N-SAS comprised two dimensions (vertical and horizontal), four domains (relationship with God; meaning of life and self-integration; self-transcendence; and relationship with others, neighborhoods, and nature), and 44 items were identified. Total Cronbach's α was .97; those of each subscale ranged from .79 to .98. N-SAS scores were positively correlated with the scores of Howden's Spiritual Assessment Scale (r=.81, p<.001). Conclusion: Findings suggest that the N-SAS can be used to measure spirituality in adults. The use of N-SAS is expected to facilitate perceiving patient's spiritual needs and providing spiritual care.