• Journal of the Korean Wood Science and Technology
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• 제26권4호
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• pp.20-25
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• 1998

Radial variation of crystalline state in a stem of Chamaecyparis obtusa E. was examined by x-ray diffraction analyses. Relative crystallinity and degree of crystallite orientation showed significant differences between juvenile and adult wood. That is, Relative crystallinity increased with increasing the age from pith to about 20th annual ring, after which it reached a more or less constant value. On the other hand, degree of crystallite orientation decreased outward from pith to about 10 years and presented almost a constant value thereafter. Crystal width by Scherrer's equation did not show any significant differences between juvenile and adult wood. Therefore, it was considered that crystallinity index and degree of crystallite orientation by x-ray diffraction method could be used for evaluating wood quality.

• Journal of Magnetics
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• 제22권2호
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• pp.188-195
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• 2017

The ferromagnetic resonance and other magnetic properties dependence on $Ni^{2+}/Fe^{3+}$ ratio and crystallite size were investigated for nano nickel ferrite ($NiFe_2O_4$). The crystallite size was controlled by controlling the nickel content in the starting material solution. The XRD and TEM were utilized to measure the crystallite size through Scherrer formula and particle size respectively. The most frequent particle sizes were lower than crystallite size, which ranged from 16.5 to 44.65 nm. The general behavior of M-H loop shapes and parameters showed superparamagnetic one. The saturation magnetization had a maximum value at $Ni^{2+}/Fe^{3+}$ molar ratio equal to 0.186. The FMR signals showed, generally, broad linewidths, where the maximum width and minimum resonance field were for the sample of the lowest crystalline size. Furthermore, FMR resonance field shows linear dependence on crystalline size. The fitting relation was estimated to express this linear dependency on the base of behavior coincidence between particle size and the inverse of saturation magnetization. The given interpretations to understand the intercept and the slope meanings of the fitted relation were based on Larmor equation, and inhomogeneous in the anisotropy constant.

• Journal of the Korean Wood Science and Technology
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• 제21권4호
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• pp.73-78
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• 1993

Crystal structure of tension, opposite and lateral wood of Platanus orientalis L. were analysed in some aspects of crystallinity index, crystallite size, d-spacing of (200) and (004), and integrated intensity ratios with X-ray diffraction method. Crystallinity index and crystallite width in tension wood appeared somewhat larger than opposite or lateral wood. However, d-spacing and integrated intensity ratios were nearly identical irrespective of tension, opposite, and lateral wood.

• Advances in materials Research
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• 제2권1호
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• pp.37-49
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• 2013

The transition metal salt doped solid polymer electrolyte [TSPE] were prepared with HPMC as a host polymer. The virgin and doped films were prepared by solution-casting method and investigated using wide angle X-ray scattering method. Micro structural parameters like lattice strain (g%), stacking/twin faults, the average number of unit cells counted in a direction perpendicular to the Bragg's plane (hkl) spacing of (hkl) planes dhkl, crystallite size Ds, distortion width, standard deviation were determined by whole pattern powder fitting (WPPF) method, which is an extension of single order method. It is found that the crystallite size decreases with the increase in the content of $FeCl_3$. This decrease is due to increase in localized breaking of polymer network which also accounts for the amorphous nature of the material. The filler inorganic salt $FeCl_3$ acts as plasticizer. FTIR study also confirms and justifies the interaction between the polymer and in-organic salt in the matrix. Physical properties like mechanical stability and Ac conductivity in these films are in conformity with the X-ray results.

• Journal of the Korean Wood Science and Technology
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• 제46권3호
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• pp.231-240
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• 2018

대나무는 생장이 빠르고, 벌목주기가 짧으며, 목재와 비교하여 가격이 저렴하다는 장점을 가지는 주요 바이오매스 자원 중 하나이다. 따라서, 본 연구에서는 대나무재의 효율적 활용을 위한 기초자료를 수집하기 위하여, 국내산 맹종죽(Phyllostachys pubescens)의 1년생~5년생까지 죽령별로 해부학적 특성을 광학현미경과 주사전자현미경으로 비교 분석하였다. 또한 셀룰로오스의 결정특성을 X선회절법에 의해 분석하였다. 횡단면 관찰 결과, 유관속초의 크기는 1년생이 가장 작았으며, 2년생 이후 유사하였다. 수 부분에서 표피부로 갈수록 유관속의 분포밀도가 높았고, 유관속초의 발달 형태가 뚜렷하게 달랐다. 특히, 1년생 수 부분 유관속 중 세포간극에 인접한 유관속초가 발달 되지 않은 유관속이 드물게 출현하는 것이 관찰되었다. 구성세포 치수 측정 결과, 섬유길이는 1년생이 가장 짧았으며, 모든 년생에서 표피부가 수 부분보다 길었다. 유관속의 방사 및 접선방향 폭은 모든 년생에서 접선방향 폭이 더 컸으며, 2년생부터는 큰 차이를 보이지 않았다. 도관 직경 및 내층 두께는 1년생의 값이 가장 작았으며, 도관 직경은 2년생 이후, 내층 두께는 3년생 이후부터 유사한 값을 보였다. 상대결정화도는 모든 년생에서 표피부로 갈수록 높은 값을 보였으며, 1년생의 값이 가장 낮고, 2~5년생은 비슷한 값을 보였다. 결론적으로, 국내산 맹종죽은 죽령별로 조직구조에 있어 정성적 및 정량적 차이가 있었으며, 2~5년생의 특성은 비슷한 경향이 있었다. 따라서, 1년생은 미성숙한 상태이며, 2년생 이상의 대나무는 성숙한 상태로 조직구조적으로 안정된 특성을 갖는 것으로 사료된다.

• 한국재료학회지
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• 제32권2호
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• pp.66-71
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• 2022

In this article, Pb₂Ba_1.7Sr_0.3Ca₂Cu₃O_10+δ superconductor material was synthesized using conventional solid-state reaction method. X-ray diffraction (XRD) analysis demonstrated one dominant phase 2223 and some impurities in the product powder. The strongest peaks in the XRD pattern were successfully indexed assuming a pseudo-tetragonal cell with lattice constants of a = 3.732, b = 3.733 and c = 14.75 Å for a Pb-Based compound. The crystallite size and lattice strain between the layers of the studied compound were estimated using several methods, namely the Scherrer, Williamson-Hall (W.H), size-strain plot (SSP) and Halder Wagner (H.W) approach. The values of crystallite size, calculated by Scherrer, W.H, SSP and H.W methods, were 89.4540774, 86.658638, 87.7555823 and 85.470086 Å, respectively. Moreover, the lattice strain values obtained by W.H, SSP and H.W methods were 0.0063240, 0.006325 and 0.006, respectively. It was noted that all crystallite size results are consistent; however, the best method is the size-strain plot because it gave a value of R² approaching one. Furthermore, degree of crystallites was calculated and found to be 59.003321%. Resistivity analysis suggests zero-resistance, which is typical of superconducting materials at critical temperature. Four-probe technique was utilized to measure the critical temperature at onset T_c(onset), zero resistivity T_{c(off set)}, and transition (width ΔT), corresponding to temperatures of 128 K, 116 K, and 12 K, respectively.

• 임산에너지
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• 제20권1호
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• pp.62-72
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• 2001

목재의 알칼리 팽윤특성을ㄹ 해명하기 위해 국내산 주요 침·활엽수 4수종의 주요 구성요소의 알칼리 팽윤 거동을 횡단면 절편을 이용하여 조사하였다. 그 결과, 일본잎갈나무의 가도관 직경은 잣나무보다 크게 팽윤하였으며, 가도관의 벽두께는 10% 이상의 알칼리 수용액에 처리시 높은 팽윤율을 나타냈다. 알칼리 처리에 의해 도관의 직경은 방사방향으로 수축하였고, 접선방향으로 다소 팽윤하였다. 목섬유의 세코벽두께는 5%의 알칼리처리에서도 수분팽윤에 비해 3배 이상의 높은 팽윤성을 나타앴고, 알칼리 처리후 일본잎갈나무의 가도관 직경, 목섬유 직경 및 세포벽두께는 거의 등방적인 수축현상을 보여주었다. 또한 미처리 시료에 비해 머서화 처리 구성요소의 세포직경은 수축되었고, 세포벽은 팽윤되었다. 알칼리처리 과정에서 셀룰로오스 결정형의 변화는 없었지만 상대결정화도와 미결정의 폭이 다소 증가되었다. 결론적으로 알칼리의 농도, 수종, 세포의 종류가 목재의 알칼리 팽윤 특성에 크게 관여하는 것으로 생각되었다.

• Journal of the Korean Wood Science and Technology
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• 제45권4호
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• pp.369-381
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• 2017

The objective of this study was to compare the wood anatomical characteristics of local tree species in Moluccas, Indonesia i.e., Moluccan ironwood (Intsia bijuga), linggua (Pterocarpus indicus), red meranti (Shorea parvifolia), and gofasa (Vitex cofassus). Qualitative evaluation was conducted by observing the anatomical structure in cross, radial, and tangential sections of each sample. For the quantitative evaluation, the dimensions of vessels, rays, and fibers were measured. Qualitative evaluation showed that crystals were observed in Moluccan ironwood, linggua, and gofasa, while resin canals were only observed in red meranti. Tyloses were frequently observed in gofasa but infrequently observed in linggua and red meranti. Quantitative evaluation showed that Moluccan ironwood with the higher density had thicker fiber wall, higher quantity of ray number, and wider rays than the other species. Red meranti had higher values of ray height and fiber length than the other three species. The results also revealed that linggua showed the highest values of relative crystallinity and crystallite width. Red meranti and gofasa showed similar values of relative crystallinity and crystallite width, while Moluccan ironwood showed the lowest values. The basic qualitative and quantitative anatomical characteristics discussed could provide useful information for further utilizations of such wood species.

• Journal of the Korean Wood Science and Technology
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• 제20권1호
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• pp.28-37
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• 1992

Fine structures of some Korean woods were investigated by X-ray diffraction methods. Relative crystallinity measured by the Segal's method and by the area method was $53{\pm}6%$ and $43{\pm}8%$ in softwoods, and $54{\pm}5%$ and $45{\pm}5%$ in hardwoods, respectively. The crystallite dimension in width was $3.11{\pm}0.45nm$ in softwoods and $3.22{\pm}0.25nm$ in hardwoods. In the longitudinal direction, the dimension was $12.79{\pm}0.89nm$ in softwoods and $12.60{\pm}0.72nm$ in hardwoods. The d-spacings of (200) in equatorial and (004) in meridional layers were about 0. 397 run and about. 0.260 nm, respectively. As a result, relative crystallinity, crystallite dimensions and d-spacings of (200) did not show any differences between the softwoods and hardwoods. The ratio of integrated intensities of (002) and (004), however, showed some differences between the softwoods and hardwoods. Namely, it was $0.101{\pm}0.027$ in softwoods and $0.138{\pm}0.037$ in hardwoods.

• Journal of the Korean Wood Science and Technology
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• 제36권1호
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• pp.12-20
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• 2008

국내에서 성장한 주요 침엽수 3종(소나무, 잣나무, 리기다소나무)의 수간 내 셀룰로오스 상대결정화도와 결정폭에 대한 수평방향 및 수직방향 변이를 X선 회절법에 의해 조사하였다. 각 수종의 상대결정화도 평균값은 소나무 60.6%, 잣나무 61.7%, 리기다소나무 49.4%로 리기다소나무가 가장 낮게 나타났다. 공시 수종의 상대결정화도는 약 10~15연륜까지 증가하다가 그 후 거의 일정한 값을 보여 주었고 만재부의 상대결정화도가 조재부의 상대결정화도보다 다소 높게 나타나는 경향이 있었다. 소나무 상대결정화도는 수관부보다 기부에서 다소 낮게 나타났으나 잣나무, 리기다소나무는 수고에 따른 차이를 거의 나타내지 않았다. 각 수종의 셀룰로오스 결정폭은 3수종 모두 2.8~3 nm 정도로 거의 차이가 없었고 수평방향 및 수직방향, 조만재 간에도 차이가 없었다. 따라서 상대결정화도와 결정폭 중 상대결정화도는 국내산 주요 침엽수재의 미성숙재와 성숙재를 구분하는 재질 지표의 하나로 이용이 가능할 것으로 생각되었다.