| Project/Area Number |
62880014
|
|---|
| Research Category |
Grant-in-Aid for Developmental Scientific Research
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
結晶学
|
|---|
| Research Institution | National Laboratory for High Energy Physics |
|---|
Principal Investigator |
OHSUMI Kazumasa National Laboratory for High Energy Physics, 放射光実験施設, 助教授 (70011715)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SATOW Yoshinori University of Tokyo, 薬学科, 教授 (30150014)
SUENO Shigeo University of Tsukuba, 地球科学系, 教授 (30110513)
OHMASA Masaaki University of Tsukuba, 物資工学系, 助教授 (30092159)
|
|---|
| Project Period (FY) |
1987 – 1988
|
| Project Status |
Completed (Fiscal Year 1988)
|
| Budget Amount *help |
¥10,000,000 (Direct Cost: ¥10,000,000)
Fiscal Year 1988: ¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1987: ¥8,000,000 (Direct Cost: ¥8,000,000)
|
|---|
| Keywords | micrometer-size crystal / submicron / structure analysis / synchrotron radiation / ラウエ法 |
|---|
| Research Abstract |
In the field of material sciences, it has long been desired for developing the equipment to obtain crystallographic information of micrometer-size crystalline substances such as very minute minerals obtained from earth or meteorites. Synchrotron radiation(SR) could be a candi-date to deal with such a small specimen because of its high intensity.
Even in the case of SR, special care should be paid for the measurement of very weak diffracted intensities. In the case not using SR, the size of fifty micrometers might be the limit for the specimen to be examined by diffraction method. The diffracted intensity is proportional to the volume of specimen, and that of micrometer sized crystal is estimated as 10^<-5> times of that of the limit mentioned above. The noise level of the experiment, therefore, should be as low as possible. If the noise level becomes negligibly small, the signal could be accumulated continually to the desired intensity level by adjusting measuring time. The experiment,for the purpose, should be carried out in vacuum with stationary crystal method and with very narrow collimated X-ray beam.
The Laue method is employed by the above reason as well as the fact that the intensitiy of each Bragg reflection on a reciprocal row passing through the origin of the reciprocal space is superposed with each other, which also intensifies a diffraction spot on the photographic plate.
The Laue camera is set up at BL-4B (located at 20 m from source point) of Photon Factory, sealed in vacuum and installed in very narrow collimater. The development of the system has been performed to the level at which several Bragg reflections of molybdenum single crystal with 0.8 micrometer in its diameter can be taken on the imaging plate for fifty minutes ex-posure with ring current from 128 to 125 mA. The obtained Laue photograph is found to be in good agreement with the calculated pattern.
|
