• Title/Summary/Keyword: 선(線)

Search Result 102, Processing Time 0.019 seconds

Matrix Effects on X-Ray Fluorescence Intensities in Fe-Ni-Cr System (철-니켈-크롬 三成分系에서 X-線 螢光의 매트릭스 效果에 관한 硏究)

  • Yang Che-Hyon;Yeh Jin-Hae
    • Journal of the Korean Chemical Society
    • /
    • v.37 no.10
    • /
    • pp.861-866
    • /
    • 1993
  • In general, the concentration of constituents can be more accurately measured in x-ray fluorescence analysis of Fe-Ni-Cr alloy by reducing and correcting the matrix effect with standard ingot samples. Because of the difficult the treatment at a high temperature in preparing the ingot samples of various concentrations, several standard specimens were prepared by mixing the powders of the metallic oxides in certain proportions and pressing them with a costant pressure. With the metallic oxide specimens thus obtained, different matrix coefficients were calculate from the intensities of the strength of the x-ray fluorescence and the concentration of the substances. It is found that effects of Fe and Cr on Ni are absorption rich and effects of Fe and Ni on Cr are enhancement rich, whereas Ni enhances Fe Fluorescence but Cr absorves Fe K${\alpha}$ line. And the x-ray fluorescence intensities were compared and analyzed between the metallic oxides and the ingot samples.

  • PDF

The Morphological Standards of Sella Turcica by Means of Roentgeno-Cephalometric Analysis (두부(頭部) X-선(線) 규격사진법(規格寫眞法)에 의(依)한 한국인(韓國人) 하수체와(下垂體窩)의 형태학적(形態學的) 연구(硏究))

  • Chang, Ik-Tae
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.8 no.1
    • /
    • pp.85-89
    • /
    • 1968
  • The author has carried out the statistical standards on liner and angular measurements of sells turcica in 244 normal Korean of various age group by means of lateral cephalometric radiography. The results were as follows; 1. The linear measurements between Ant-Post distance and distance from the tip of tuberculum of sellae to posterior clinoid process were obtained 14.81mm, 9.85mm in the age of 5 years old male and 14.44mm, 9.52mm in female, respectively. There was no outstanding difference with age, but more predominant in female than male. 2. The linear measurements of inferior depth show somewhat increases but no changes in superior depth. 3. It has been showed that the greatest width revealed significant increment beyond 15 years old of both sexes in Korean. 4. None of the significant difference in angular measurement was found with age, but angulation for dorsum sellae decreased after 15 years of male. 5. Generally speaking, increment rates of female in each items were greater than male.

  • PDF

Calculation of Neutron and Gamma-Ray Flux-to-Dose-Rate Conversion Factors (중성자(中性子) 및 감마선(線)에 대한 선량율(線量率) 환산인자(換算因子) 계산(計算))

  • Kwon, Seog-Guen;Lee, Soo-Yong;Yook, Chong-Chul
    • Journal of Radiation Protection and Research
    • /
    • v.6 no.1
    • /
    • pp.8-24
    • /
    • 1981
  • This paper presents flux-to-dose-rate conversion factors for neutrons and gamma rays based on the American National Standard Institute(ANSI) N666. These data are used to calculated the dose rate distribution of neutron and gamma ray in radiation fields. Neutron flux-to-dose-rate conversion factors for energies from $2.5{\times}10^{-8}$ to 20 MeV are presented; the corresponding energy range for gamma rays is 0.01 to 15 MeV. Flux-to-dose-rate conversion factors were calculated, under the assumption that radiation energy distribution has nonlinearity in the phantom, have different meaning from those values obtained by monoetiergetic radiation. Especially, these values were determined with the cross section library. The flux-to-dose-rate conversion factors obtained in this work were in a good agreement to the values presented by ANSI. Those data will be a useful for the radiation shielding analysis and the radiation dosimetry in the case of continuous energy distributions.

  • PDF

A Study on the Chest Radiographic Condition in Adult. (흉부X-선(胸部X-線) 촬영조건(撮影條件)에 대(對)한 고찰(考察))

  • Lee, Sang-Suk;Youn, Chul-Ho;Joo, Kuang-Tai;Park, Sung-Ock
    • Journal of radiological science and technology
    • /
    • v.2 no.1
    • /
    • pp.31-35
    • /
    • 1979
  • A thorax is consisted of a heart, great vesseles, lungs, ribs, sternum and thoracic spine etc. The quality of chest radiogram is very important in order to find out abnormality in the lung field. The image has two major characteristics; density and contrast which directly influence the diagnostic quality of the roentgenogram. It is very hard to make excellent film image in the lung field because of overlapping bones and other soft tissues. To take a good radiogram of lung field, we studied the condition of chest P-A projection in adult and obtained results as follows: 1. The average chest radiographic condition is resulted as 62KVP, 16 mAs in hospitals around Kyung Ki-Do, Korea, 2. The density of the chest 20cm in thickness, is equal to the water phantom 8cm in thickness. 3. The best quality of chest radiogram is achieved in the condition of the lung field at 100KVP, 9.6mAs by use of Grid 8:1.

  • PDF

A Study on Film Sensitive Effect Influenced by ${\gamma}-ray$(Ir-192) Depending on Thickness of Lead Foil ($\gamma$선(線)(Ir-192)이 연박(鉛箔)두께의 증감(增減)에 따른 필름감도(感度) 효과(效果))

  • Joo, Gwang-Tae
    • Journal of radiological science and technology
    • /
    • v.2 no.1
    • /
    • pp.95-99
    • /
    • 1979
  • When the ${\gamma}-ray$ of average energy 375KeV emitted by Ir-192 is exposed to each film through lead foil with various thickness, the film sensitivity will be different according to the thickness of lead foil and film type. The results on the study, different density and sensitive ratio appeared depending on exposed time and film type, but was made on the following common points. 1. The effect of film sensitivity by the front lead foil showed rapid increase up to the thickness of more or less 0.03mm, and the thicker lead foil was decreased more in the thickness of about $0.05{\sim}0.09mm$. 2. The effect of film sensitivity by the back lead foil was increased up to around of $0.03{\sim}0.08mm$ thickness, the maximum sensitivity was obtained in the thickness of more than $0.03{\sim}0.08mm$ without any change in the above effect. 3. The sensitivity of front lead foil was higher than that of back lead foil in thin lead foil with about 0.127mm thickness, but the sensitivity of back lead foil was higher than that of front lead foil when thickness became thicker.

  • PDF

The Optical Illusion Effect of Line Applied to Eyebrow Make-up (눈썹 메이크업 표현(表現)에 응용(應用)되는 선(線)의 착시(錯視) 효과(效果))

  • Ha, Sun-Ok;Cho, Koh-Mi;Kim, Chun-Sim
    • Journal of Fashion Business
    • /
    • v.9 no.2
    • /
    • pp.28-39
    • /
    • 2005
  • This chapter presents how 'optical illusion' works in applying makeup and how to differentiate the direction, location and shape at eyebrow lines in the aspect at physiognomy. For this study, employed were five types of face shape produced by Photoshop program - round, square, long, inverted triangle. and diamond. The best-matched facial shape was examined through a questionnaire research after applying the optical illusion of eyebrow lines to the five types of face shape. The results were revealed to be identical to ones presented in make-up teaching materials. In conclusion, it was found that well-matched shape and size of eyebrow could make some changes in the facial impression, changing the face shape into oval shape. The facial line can be modified and supplemented by reshaping such facial parts as the eyebrow, producing well-balanced facial shape. Consequently, make-up was proved to be one of the methods which can be used to create social and psychological effect which can make a favorable facial impression and individuality, natural impression and image making depending on different purposes, taking advantage of optical illusion effect.

The Effects of Co-60 ${\gamma}-irradiation$ causing Enzyme Histochemical Changes of Bursa Fabricius, Thymus and Spleen in Chicken (Co-60 ${\gamma}$선(線) 조사(照射)가 병아리의 F낭, 흉선 및 비장의 효소(酵素) 조직화학적(組織化學的) 변화(變化)에 미치는 영향(影響))

  • Lee, Dong-Myoung
    • Journal of radiological science and technology
    • /
    • v.13 no.1
    • /
    • pp.29-35
    • /
    • 1990
  • In a attempt to find out the effects of the irradiation on the lymphatic organs of birds, a total of 40 chickens(4 week old) were selected at random and alloted to control and experimental groups. The experiments were irradiated Co-60 ${\gamma}-ray/400$ rads, and then the enzyme histochemical activity of Bursa Fabricious(BF), thymus and spleen and hematological changes were compared with those of controls for 30 days(24 hrs., 5, 10, 20 and 30 days). The results obtained were summarized as follows: 1. The activity of acid phosphatase(ACP) of the reticuloendothelial cells of BF, thymus and spleen and the epithelia of BF of the experiments were increased significantly from the early experimental terms and then returned to the same level of controls through the late experimental terms. 2. The activity of nonspecific esterase(NSE) of the constituent cells with exception of the lymphocytes in BF, thymus and spleen of experiments were increased significantly from the early experimental terms and then returned to the same level of control through the late experimental terms. 3. The lymphocyte percentage, total erythrocytes and homoglobin of the experiments were severely decreased from early experimental terms and then increased to the normal levels of them incontrols.

  • PDF

A Study on Scattering Distribution in Metal of Ir-192 Gamma-Ray (Ir-192 $\gamma$선(線)의 금속(金屬)에 대(對)한 산란분포(散亂分布)에 관(關)한 연구(硏究))

  • Joo, Gwang-Tae
    • Journal of radiological science and technology
    • /
    • v.4 no.1
    • /
    • pp.63-71
    • /
    • 1981
  • The metal-plates(Aluminium. Copper, Lead) of change the variation thickness have been penetrated by the collimated beam($450mm{\times}4mm{\phi}$) of Gamma-ray from $^{192}Ir$. Then, the scattered $\gamma$-ray dose in variable angle and the directly transmitted $\gamma$-ray dose were measured using the electrometer of ionization chamber. The results were summarized as follows: 1. Obtained the mass attenuation coefficients of $Al;0.0937cm^2g^{-1},\;Cu;0.0937cm^2g^{-1},\;pb;0.244cm^2g^{-1}$. 2. Total intensity of front scattered $\gamma$-ray follow the order of Al>Cu>pb. 3. The scattered $\gamma$-ray intensity with the lager angle of scattering was saturated after increase rapidly, and the scattering angle of the more larger was decreased. 4. The scattered $\gamma$-ray intensity through plates of aluminium or copper was saturated after increase with thicker scatterer, and the intensity was decreased at the more thicker. But the variation of scattered $\gamma$-ray dose in the lead plate made the fewest than Al and Cu. 5. The ratio of the scattered $\gamma$-ray dose and the directly transmitted $\gamma$-ray dose was saturated after increase with the thicker scatterer, and the scatterer of the more thicker was decreased. Degree of total intensity in these ratios was followed the order of Cu>Al>Pb.

  • PDF

A Measurement of the Exposure Rates by Terrestrial y-rays in Taegu Area (대구지역(大邱地域) 지각(地殼) ${\gamma}$-선(線)의 조사선량율(照射線量率) 측정(測定))

  • Chang, Si-Ho;Jeong, Chun-Gyun;Kang, Hee-Dong;Lee, Mo-Sung;Choi, Mun-Kyu;Kim, Wi-Soo
    • Journal of Radiation Protection and Research
    • /
    • v.19 no.2
    • /
    • pp.121-132
    • /
    • 1994
  • This study concerns about the measurement and the investigation of environmental radiation characteristics which the components and the distribution of exposure rates by terrestrial y-rays in Taegu area. $4^{'}{\phi}{\times}4^{'}$ NaI(T1) scintillation detector with a multichannel analyzer was used in the measurement of y-rays as a part of in-situ spectrometry at twenty eight different locations in this area. The conversion into the exposure rate from the measured ${\gamma}-ray$ spectrum has been carried out leading to a net exposure rate and component ones by $^{40}K,\;^{238}U$ series and $^{232}Th$ series products which are known by the major parts in the terrestrial ${\gamma}-rays$ generally. As a result, the average exposure rate by the terrestrial ${\gamma}-rays$ in Taegu area is $9.4{\mu}R/h$ and the distribution of individual exposure rates shows more or less differences between these locations even after the consideration of diurnal and yearly variations which are always involved in these measurements. The component parts of exposure rates are distributed $^{40}K\;2.9{\sim}4.6{\mu}R/h,\;^{238}U$ series $1.2{\sim}3,\;1{\mu}R/h,\;^{232}Th$ series $2.5{\sim}5.0{\mu}R/h$ over the measured locations.

  • PDF

Change of Dose Distribution on the Beam Axis of 60Co γ Ray and 10MV X-Ray with Part Thickness (치료부위(治療部位)두께에 따른 Co-60 γ선(線)과 10MV X선(線)의 선축상(線軸上) 선량분포(線量分布)의 변화(變化))

  • Kang, Wee Saing;Koh, Kyoung Hwan;Ha, Sung Whan;Park, Charn Il
    • Radiation Oncology Journal
    • /
    • v.1 no.1
    • /
    • pp.21-24
    • /
    • 1983
  • The thickness of the part being irradiated is finite. Percent depth dose tables being used routinely are generally obtained from dosimetry in a phantom much thickner than usual patient. At or close to exit surface, the dose should be less than that obtained from the percent depth dose tables, because of insufficient volume for backscattering. To know the difference between the true absorbed dose and the dose obtained from percent depth dose table, the doses at or close to the exit surface were measured with plate type ionization chamber with volume of 0.5ml. The results are as follows; 1. In the case of $^{60}Co$, percent depth dose at a given depth increases with underlying phantom thickness up to the 5cm. 2. In the case of $^{60}Co$, the dose correction factor at exit surface which is less than 1, increases with part thickness and decreases with field size. 3. Exposure time may not be corrected when the part above 10cm in thickness is treated by $^{60}Co$. 4. In the case of 10MV x-ray, the dose correction factor is nearly 1 and constant for the underlying phantom thickness and field size, so the correction of monitor unit is not necessary for part thickness.

  • PDF