• Progress in Medical Physics
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• v.22 no.2
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• pp.72-78
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• 2011

The aim of this study is to evaluate the patient's setup errors in TomoTherapy (Hi-Art II, TomoTherapy, USA) Bodyfix system (Medical Intelligence, Ele-kta, Schwabmuchen, Germany) pressure in the vacuum compression, depending on and were evaluated. Bodyfix immobilization system and vacuum pressure was compression applied to the patients who received Tomotherapy thoracic and abdominal area, 21 patients were selected and TomoTehpay treatment total 477 of MVCT images were obtained. The translational (medial-lateral: ML, anterior-posterior: AP, superior-inferior: SI directions) and rolling were recorded and analyzed statistically. Using Pearson's product-moment coefficient and One-way ANOVA, the degree of correlation depending on the different vacuum pressure levels were statistically analyzed for setup errors from five groups (p<0.05). The largest average and standard deviation of systematic errors were 6.00, 5.95 mm in the AP and SI directions, respectively. The largest average of random errors were 4.72 mm in the SI directions. The correlation coefficients were 0.485, 0.244, and 0.637 for the ML-Roll, AP-Vector, and SI-Vector, respectively. SI-Vector direction showed the best relationship. In the results of the different degree of vacuum pressure in five groups (Pressure range: 30~70 mbar), the setup errors between the ML, SI in both directions and Roll p=0.00 (p<0.05) were shown significant differences. The average errors of SI direction in the vacuum pressure of 40 mbar and 70 mbar group were 4.78 mm and -0.74 mm, respectively. In this study, the correlation between the vacuum pressure and the setup-errors were statistically analyzed. The fact that setup-errors in SI direction is dependent in vacuum pressure considerly setup-errors and movement of interal organs was identified. Finally, setup-errors, and it, based on the movement of internal organs in Bodyfix system we should apply more than 50 mbar vacuum pressure. Based on the results of this study, it is suggested that accuracy of the vacuum pressure and the quantitative analysis of movement of internal organs and the tumor should be studied.

• Economic and Environmental Geology
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• v.34 no.1
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• pp.133-146
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• 2001

We report the results of structural field observation and measurement of anisotropy of magnetic susceptibility (AMS) of the diamictitic Hwanggangri Formation distributed in Chungju-Suanbo area of the Okchon Belt, Korea. The outcrops of the Hwanggangri Formation show two types of cleavage in general: slaty cleavage (SI) and crenulation cleavage (5z). 5] cleavage is, however, well observable only in the notheastem (NE) part of study area, while overwhelmed by 52 cleavage in the southwestern (5W) part, indicating stronger later deformation in 5W part of the study area. This partitioning of the study area is corroborated by both IRM and AMS parameters: NE part of the study area is characterized by higher IRM intensity, higher bulk magnetic susceptibility, higher AM5 degree, and by oblate shape of magnetic susceptibility ellipsoid. Their values become drastically lowered toward southwest, and reach to a stable minimum in the whole 5W part of the study area. In addition, degree of both metamorphism and deformation tends to increase gradually from northeast toward southwest and also from northwest toward southeast in the study area. Based on the distribution pattern of the principal axes ( $k_1, k_2, k_3$ axes) of magnetic anisotropy ellipsoids revealed in the NE part of the study area, three episodes of deformation ( $D_1, D_2, D_3$ ) are recognized: D_1$ deformation produced $S_2$ cleavage with NE-5W trend, which is caused by a strong NW-SE tlattening of a coaxial pure shear. $D_2$ deformation produced 5z cleavage characterized by a non-coaxial deformation. It was caused by a ductile or semi-ductile thrusting toward NW and concurrent sinistral shearing along $S_2$ cleavage plane. Lastly, $D_3$ deformation produced tlexural folding of all previous structures with a nearly horizontal NE fold axis. Distribution pattern of the principal axes of magnetic anisotropy ellipsoid from the SW part of the study area, on the other hand, does not show any coherency among sites or samples. We interpret that this dispersed pattern of $k_1, k_2, k_3$ axes together with lower anisotropy strength indicates that magnetic fabrics in the SW part have been disturbed either by a superposition of strong deformation/metamorphism or by a kind of reciprocal strain due to an overlapping of $D_1$ and $D_2$ or by both processes.

• The Korean Journal of Nuclear Medicine Technology
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• v.21 no.2
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• pp.80-85
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• 2017

Purpose The D530c have cadmium zinc telluride(CZT) detectors that are arranged focus on the heart. This structural characteristic allows for quicker imaging without rotation, but this is sensitive to patient movement and can affect the test results. The aim of this study is to optimize the image quality by reducing patient movement during the examination. Materials and Methods We analyzed the patients' movements, and performed various activities such as provided patient education about correct breathing techniques and avoiding patient movements, and created breathing correction tools to minimize patient movement during exam. The 70 patients who underwent myocardial perfusion SPECT with D530c in November 2016 were categorized as the group before the corrective steps. Another 70 patients who underwent the procedure with D530c from February 14, 2017 to February 21, 2017 were categorized as the improvement group. Images acquired during stress and at rest were compared and analyzed by measuring the durations of heart movements over certain distances (4 mm, 8 mm, 12 mm, or more) noted on the x-, y-, and zaxes. Results After the activities, the durations of heart movements decreased in the images acquired both under stress and at rest. In particular, there were no large motions greater than 12 mm recorded in the stress images after the improvement. There was a significant difference (p<0.005) in the 4-mm and 8-mm fluctuations on the X-axis and the 8-mm fluctuations on the Z axis in the stress images, but there was no significant difference (p>0.005) in the other stress and rest intervals. Conclusion The decrease in the time of motion occurrence due to the 4 mm fluctuation distance that can occur through breathing can be understood as a result of the breathing being corrected through training and motion prevention tools. It is expected that the image quality will be improved by reducing the occurrence time according to the variation distance of 8 mm or 12 mm, which is expected as the actual movement of the patient other than the breathing.

• Journal of the Mineralogical Society of Korea
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• v.30 no.2
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• pp.45-57
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• 2017

Two single crystals of fully dehydrated $Cd^{2+}$-exchanged zeolites Y were prepared by the exchange of ${\mid}Na_{75}{\mid}[Si_{117}Al_{75}O_{384}]-FAU$ ($Na_{75}-Y$, Si/Al = 1.56) with aqueous $0.05M\;Cd(NO_3)_2$ (pH = 3.65) at 294 K, followed by vacuum dehydration at 723 K (crystal 1) and a second crystal, similarly prepared, was exposed to zeolitically dried benzene for 72 hours at 294 K and evacuated (crystal 2). Their structures were determined crystallographically using synchrotron X-rays and were refined to the final error indices using $F_o$>$4{\sigma}(F_o)$ of $R_1/wR_2=0.040/0.121$ and 0.052/0.168, respectively. In crystal $1({\mid}Cd_{36}H_3{\mid}[Si_{117}Al_{75}O_{384}]-FAU)$, $Cd^{2+}$ ions primarily occupy sites I and II, with additional $Cd^{2+}$ ions at sites I', II', and a second site II. In crystal $2({\mid}Cd_{35}(C_6H_6)_{24}H_5{\mid}[Si_{117}Al_{75}O_{384}]-FAU)$, $Cd^{2+}$ ions occupy five crystallographic sites. The 24 benzene molecules are found at two distinct positions within the supercages. The 17 benzene molecules are found on the 3-fold axes in the supercages where each interacts facially with one of site IIa $Cd^{2+}$ ions. The remaining 7 benzene molecules lie on the planes of the 12-rings where each is stabilized by multiple weak electrostatic and van der Waals interactions with framework oxygens.

• Journal of the Korean Chemical Society
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• v.33 no.5
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• pp.452-458
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• 1989

The crystal structures of vacuum-dehydrated $Ag^+\;and\;Ca^{2+}$ exchanged zeolite A, Ag_7Ca_{2.5}-A(a = 12.310(1){\AA})$ and $Ag_2Ca_5-A(a = 12.287(2){\AA})$ have been determined by single-crystal X-ray diffraction methods in the cubic space group Pm3m at $21(1)^{\circ}C$. The crystals of $A_7Ca_{2.5}-A\;and\;Ag_2Ca_5-A$ were prepared by flow method using exchange solutions in which mole ratios of $AgNO_3\;and\;Ca(NO_3)_2$ were 1:50 and 1:1000, respectively, with total concentration of 0.05 M. Full-matrix least-squares refinement converged to the final error indices of R1 = 0.056 and R2 = 0.059 for $Ag7Ca2.5-A$, and R1 = 0.054 and R2 = 0.082 for $Ag2Ca5-A$ using 306 and 348 reflections, respectively, for which I >3 {\sigma}$ (I). 5.5 $Ag^+$ ions and 2.5 Ca^{2+}$ ions for $Ag_7Ca_{2.5}-A\;and\;2\;Ag^+$ ions and 5 $Ca^{2+}$ ions for $Ag_2Ca_5-A$ lie on two crystallographically nonequivalent threefold axes on the 6-rings. Both structures indicate that smaller Ca2+ ions preferentially occupy 6-ring sites and larger $Ag+$ ions occupy 8-ring sites when total number of cations per unit cell is more than 8.

• Journal of the Korean Chemical Society
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• v.38 no.3
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• pp.186-196
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• 1994

Three fully dehydrated partially $Ag^+$-exchanged zeolite A(Ag_4Na_8-A, Ag_6Na_6-A, and Ag_8Na_4-A) were treated at $250^{\circ}C$ with 0.1 torr Rb vapor at 4 h. Their structures were determined by singlecrystal X-ray diffraction methods in the cubic space group $Pm{\bar3}m$ (a = 12.264(4) $\AA$, a = 12.269(1) $\AA$, and a= 12.332(3) $\AA$, respectively) at $22(1)^{\circ}C$, and were refined to the final error indices, R(weighed), of 0.056 with 131 reflections, 0.068 with 108 reflections, and 0.070 with 94 reflections, respectively, for which I > $3\sigma(I).$ In these structures, Rb species are found at three different crystallographic sites; three $Rb^+$ ions per unit cell are located at 8-ring centers, ca. 6.0∼6.8 $Rb^+$ ions are found opposite 6-rings on threefold axes in the large cavity, and ca. 2.5 $Rb^+$ ions are found on three fold axes in the sodalite unit. Also, Ag species are found at two different crystallographic sites; ca. 0.6∼1.0 $Ag^+$ ion lies opposite 4-rings and about 1.8∼4.2 Ag atoms are located near the center of the large cavity. In these structures, the numbers of Ag atoms per unit cell are 1.8, 3.0, and 4.2, respectively, and these are likely to form hexasilver clusters at the centers of the large cavities. The $Rb^+$ ions, by blocking 8-rings, may have prevented silver atoms from migrating out of the structure. Each hexasilver cluster is stabilized by coordination to 6-ring, 8-ring $Rb^+$ ions, and also by coordination to a 4-ring $Ag^+$ ion.

• Journal of the Korean Chemical Society
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• v.35 no.3
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• pp.189-195
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• 1991

Two crystal structures of dehydrated $Ag_{2.8}ZN_{4.6}-A$ and of its ethylene sorption complex have been determined by single-crystal X-ray diffraction techniques. The structures were solved and refined in the cubic space group Pm3m at 23(1)$^{\circ}$C. Dehydration of two crystals studied were achieved at 400$^{\circ}$C and $2{\times}10^{-6}$ Torr for 2 days and one crystal was treated with 250 Torr of ethylene at 25(1)$^{\circ}$C. The structures of dehydrated $Ag_{2.8}ZN_{4.6}-A$ (a = 12.137(2) ${\AA}$ and of its ethylene sorption complex (a = 12.106(2)${\AA}$) were refined to final error indices, R(weighted) = 0.044 with 237 reflections and R(weighted) = 0.050 with 301 reflections, respectively, for which I > 3${sigma}$(I). 2.8 $Ag^+$ ions are recessed 0.922(2) ${\AA}$ from (111) plane of three 6-ring oxygens into the large cavity where each forms a lateral ${\pi}$ complex with an ethylene molecule. These $Ag^+$ ions are in 2.240(5)${\AA}$ from three framework oxide ions and 2.290(5) ${\AA}$ from each carbon atom of an ethylene molecule. The $Zn^{2+}$ ions occupy two different threefold axis positions of the unit cell. 2.8 $Zn^{2+}$ ions are recessed 0.408(2) ${\AA}$ from (111) plane of the 6-ring oxygens and each $Zn^{2+}$ ion forms a $\pi$ complex with an $C_2H_4$ molecule. The distances between $Zn^{2+}$ ions and carbon atom of ethylene molecule, Zn(2)-C = 2.78(4) ${\AA}$ are long. This indicates that this bond is relatively weak.

• Journal of the Korean Chemical Society
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• v.33 no.1
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• pp.18-24
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• 1989

Two crystal structures of dehydrated $Ag^+$ and $Rb^+$ exchanged zeolite A, stoichiometries of $Ag_{9}Rb_{3}-A$ (a = 12.278(2)${\AA}$) and $Ag_{10}Rb_{2}-A$ (a = 12.286(2)${\AA}$) per unit cell, have been determined by single crystal x-ray diffraction techniques. Their structures were solved and refined in the cubic space group Pm3m at 21(1)$^{\circ}$C. The crystals of $Ag_{10}Rb_{2}-A$ and $Ag_{10}Rb_{2}-A$ were prepared by flow methods using exchanged solution in which mole ratios of AgNO$_3$ and RbNO$_3$ were 1:5 and 1:50, respectively, with the total concentration of 0.05 M. The structures of the dehydrated $Ag_{9}Rb_{3}-A$ and the $Ag_{10}Rb_{2}-A$ were refined to the final error indices, $R_1$ = 0.064 and $R_2$ = 0.060 with 291 reflections, and $R_1$ = 0.063 and $R_2$ = 0.080 with 416 reflections respectively, for which I >3${\sigma}$(I). In both structures, one reduced silver atom per unit cell was found inside the sodalite cavity. It may be present as a hexasilver cluster in 1/6 of the sodalite units or as an isolated Ag atom coordinated to 4 $Ag^+$ ions in each sodalite unit to give $(Ag_5)^{4+}$, symmetry 4 mm. In the structure of dehydrated $Ag_{9}Rb_{3}-A$, 8 $Ag^+$ ions lie on the threefold axis and each is nearly at the center of the 8-rings at the sites of $D_{4h}$ symmetry. In the structure of dehydrated $Ag_{10}Rb_{2}-A$, two crystallographically different eight 6-ring $Ag^+$ ions were found; $7Ag^+$ ions in the (111) planes of their O(3) framework oxygens and one $Ag^+$ ion inside of sodalite cavity. Two crystallographically different 8-ring cations were also found; two $Rb^+$ ions at the centers of the 8-oxygen rings and one $Ag^+$ ion into the large cavity. Both structures indicate that $Rb^+$ ions prefer to occupy the 8-ring sites, while $Ag^+$ ions prefer to occupy the 6-ring sites.

• Journal of the Mineralogical Society of Korea
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• v.4 no.1
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• pp.22-31
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• 1991

Three crystal structures of dehydrated $Ag^+$-and $Ca^{2+}$- exchanged zeolite $A(Ag_4Ca_4-A,\;Ag_^Ca_3-A,\;and\;Ag_8Ca_2-A)$ treated at 250${\circ}C$ with 0.1 Torr of Rb vapor have been determined by single-crystal x-ray diffraction techniques in the cubic space group Pm3m at 21(1)${\circ}C$ (a=12,271(1)${\AA}$, 12.255(1)${\AA}$, and 12.339(1)${\AA}$, respectively). Their structures were refined to the final error indices. R(weighted) of 0.072 with 130 reflections, 0.050 with 110 reflections, and 0.083 with 86 reflections, respectively, for which $I>3{\rho}(I)$. In each structure, Rb species are found at three different crystallographic sites:3$Rb^+$+ions per unit cell are located at 8-ring centers, ca. 5.6 to 6.4 $Rb^+$ ions are found opposite 6-rings on threefold axes in the large cavity, and ca. 2.5 to 3.0 $Rb^+$ ions are found on threefold axes in the sodalite unit. Also, Ag species are found at two different crystallographic stites: ca. 0.7 to 2.1 $Ag^+$ lie opposite 4-rings and ca. 2.2 to 4.8 Ag atoms are located near the center of the large cavity. In these structures, the numbers of Ag atoms per unit cell are 2.2, 2.4, and 4.8, respectively, and these may form hexasilver clusters at the centers of the large cavities. The $Rb^+$ ions, by blocking 8-rings, may have prevented silver from migrating out of the structure. Each hexasilver cluster is stabilized by coordination to up to 13 $Rb^+$ions. An excess absorption of about 0.8 Rb atom per unit cell indicates that the presence of a triangular symmetric $(Rb_3)2^{+}$ cation in sodalite cavity. At least one large-cavity six-ring $Rb^+$ ion must necessarily approach this cluster and may be viewed as a member of it to give $(Rb)_4^{3+}$, $(Rb)_5^{4+}$ or $(Rb)_6^{5+}$.

• Journal of the Korean Chemical Society
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• v.40 no.6
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• pp.427-435
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• 1996

The structures of fully dehydrated $Ca^{2+}$- and $Cs^+$-exchanged zeolite X, $Ca_{35}Cs_{22}Si_{100}Al_{92}O_{384}$($Ca_{35}Cs_{22}$-X; a=25.071(1) $\AA)$ and $Ca_{29}Cs_{34}Si_{100}Al_{92}O_{384}$($Ca_{29}Cs_{34}$-X; a=24.949(1) $\AA)$, have been determined by single-crystal X-ray diffraction methods in the cubic space group Fd3 at $21(1)^{\circ}C.$ Their structures were refined to the final error indices $R_1$=0.051 and $R_2$=0.044 with 322 reflections for $Ca_{35}Cs_{22}$-X, and $R_1$=0.058 and $R_2$=0.055 with 260 reflections for $Ca_{29}Cs_{34}$-X; $I>3\sigma(I).$ In both structures, $Ca^{2+}$ and $Cs^+$ ions are located at five different crystallographic sites. In dehydrated $Ca_{35}Cs_{22}$-X, sixteen $Ca^{2+}$ ions fill site I, at the centers of the double 6-rings(Ca-O=2.41(1) $\AA$ and $O-Ca-O=93.4(3)^{\circ}).$ Another nineteen $Ca^{2+}$ ions occupy site II (Ca-O=2.29(1) $\AA$, O-Ca-O=118.7(4)') and ten $Cs^+$ ions occupy site II opposite single six-rings in the supercage; each is $1.95\AA$ from the plane of three oxygens (Cs-O=2.99(1) and $O-Cs-O=82.3(3)^{\circ}).$ About three $Cs^+$ ions are found at site II', 2.27 $\AA$ into sodalite cavity from their three-oxygen plane (Cs-O=3.23(1) $\AA$ and $O-Cs-O=75.2(3)^{\circ}).$ The remaining nine $Cs^+$ ions are statistically distributed over site Ⅲ, a 48-fold equipoint in the supercages on twofold axes (Cs-O=3.25(1) $\AA$ and Cs-O=3.49(1) $\AA).$ In dehydrated $Ca_{29}Cs_{34}$-X, sixteen $Ca^{2+}$ ions fill site I(Ca-O=2.38(1) $\AA$ and $O-Ca-O=94.1(4)^{\circ})$ and thirteen $Ca^{2+}$ ions occupy site II (Ca-O=2.32(2) $\AA$, $O-Ca-O=119.7(6)^{\circ}).$ Another twelve $Cs^+$ ions occupy site II; each is $1.93\AA$ from the plane of three oxygens (Cs-O=3.02(1) and $O-Cs-O=83.1(4)^{\circ})$ and seven $Cs^+$ ions occupy site II'; each is $2.22\AA$ into sodalite cavity from their three-oxygen plane (Cs-O=3.21(2) and $O-Cs-O=77.2(4)^{\circ}).$ The remaining sixteen $Cs^+$ ions are found at III site in the supercage (Cs-O=3.11(1) $\AA$ and Cs-O=3.46(2) $\AA).$ It appears that $Ca^{2+}$ ions prefer sites I and II in that order, and that $Cs^+$ ions occupy the remaining sites, except that they are too large to be stable at site I.