• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.8
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• pp.1102-1107
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• 1993

Microwave dielectric properties of CaTiO3 and CaTiO3-TiO2 ceramics for the composition range between 40 and 50 mol% CaO in CaO-TiO2 binary system were investigated. CaTiO3 ceramics with50 mol% CaO showed the dielectric constant (e,) of 178, the temperature coefficient of resonant frequency(c,) of+1000 ppm/'c and the qualify factor Q of 2760 (f0=2.7 GHz ). Dielectric constant and temperature coefficient of resonant frequency of ceramics with dual phases of CaTiO3 and TiO2 decreased gradually from those of CaTiO3 as the CaO content decreased. Q value and density were found to have minimum at the composition of 47 mol% CaO. The degradation of Q value and density in dual phase ceramics seems to be caused by the large pores at grain boundaries and/or within grains remained after rapid growth of CaTiO3 grains as TiO2 Phase decreased.

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.30.1-30
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• 2002

• Journal of the Microelectronics and Packaging Society
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• v.11 no.3 s.32
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• pp.17-22
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• 2004

The microwave dielectric properties of $CaZrO_3$ ceramics with addition of $CaTiO_3$ were studied. The effect of glass addition on the low-temperature sintering and microwave dielectric properties of $CaZrO_3-CaTiO_3$ ceramics were also evaluated to develop the materials for functional substrates of low-temperature co-fired ceramics. When $10-20 wt\%$ of lithium borosilicate glass was added, the sintering temperature of the $CaZrO_3-CaTiO_3$ ceramics decreased from $1450^{\circ}C$ to below $900^{\circ}C$. As the $T_f$ of glass frits and $CaZrO_3$ are slightly negative and that of $CaTiO_3$ is significantly positive, zero $T_f$ could be realized by mixing an appropriate amount of $CaTiO_3$ with $CaZrO_3$. The $CaZrO_3-CaTiO_3$ ceramics sintered at $875^{\circ}C$ with $15wt\%$ glass frits showed the relative density of $98\%$, permittivity of 23, quality factor of 2500 GHz, and temperature coefficient of resonant frequency of $ -3 ppm/^{\circ}C$.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.9
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• pp.497-507
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• 2014

This paper investigates the standard features of Carrier aggregation (CA), the related UE RF requirements in 3GPP release 12 and estimated CA evolution in future. The main CA feature of 3GPP release 12 in WG4 perspectives includes 2Uplink(UL) CA, 3Downlink(DL) CA and TDD-FDD CA. To support these features in UE, UE-to-UE coexistence problem and RF requirements generated by unwanted emissions such as inter-modulation and harmonics are analyzed. Also, future CA technology such as LTE in unlicensed bands is described.

• Journal of the Korean Ceramic Society
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• v.40 no.9
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• pp.859-866
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• 2003

When calcium sulfoaluminate-based expansive cement was hydrated, ettringite and monosulfate were mainly formed. The crack of hardened cement was prevented by compensating drying shrinkage due to formation of the above hydrates. In order to study the hydration properties of calcium sulfoaluminate-based expanding cement, 3CaOㆍ3Al$_2$O$_3$ㆍCaSO$_4$(C$_4$A$_3$S) was prepared by chemical synthesis, and then the hydration of $C_4$A$_3$S-Ca(OH)$_2$-CaSO$_4$.$2H_2O$-C$_3$A system_was characterized. Good $C_4$A$_3$S phase was prepared at $1300^{\circ}C$ by chemical synthesis, and the main hydration product of $C_4$A$_3$S-Ca(OH)$_2$-CaSO$_4$.2$H_2O$ system was ettringite. In the case of hydration $C_4$A$_3$S-Ca(OH)$_2$-CaSO$_4$ㆍ 2$H_2O$-C$_3$A system, ettringite was formed in the early period and it was transformed into monosulfate while consumed gypsum.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.2
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• pp.80-85
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• 2006

The foliar injuries and absorption rates of calcium compounds in tomato (Lycopersicon esculentum cv. momotaro) and citrus [Shiranuhi(C. Marc. ${\time}C$. sinensis Osbeck)${\time}C$. reticulata Blanco)] were investigated. 0.3, 0.5 and 1.0% of $CaCl_2$, $Ca(NO_3)_2$, $Ca(H_2PO_4)_2$, Ca-EDTA, Ca formate or Ca acetate solution were applied to the leaves of tomato and citrus. The leaf burns were observed only in the foliar applications of Ca-EDTA and $Ca(H_2PO_4)_2$. Ca-EDTA exhibited more serious foliar injury than CaH2PO4. As applied with $^{45}CaCl_2$, $^{45}Ca(NO_3)_2$, $^{45}Ca$ formate or $^{45}Ca$ acetate, the rates of Ca absorptions by tomato and citrus leaves for 7 days were 17 to 32% and 6.6 to 46%, respectively. It meant that the absorption was differently influenced on calcium compounds. In tomato, the order of Ca foliar absorption was $Ca(NO_3)_2$ > Ca formate = $CaCl_2$ > Ca acetate. Although there was no difference in Ca absorption between the adaxial and abaxial parts of tomato leaves, total absorption was greater in expanded leaves than in expanding ones. On the other hand, in citrus Ca foliar absorption from $Ca(NO_3)_2$ or Ca formate was more active than that from $CaCl_2$ or Ca acetate. In conclusion, $Ca(NO_3)_2$ and Ca formate are recommended for the foliar application of Ca in tomato and citrus in order to increase absorption of Ca into their leaves.

• The Korean Journal of Nuclear Medicine
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• v.38 no.4
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• pp.311-317
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• 2004

Purpose: The purpose of this study was to determine the utility of tumor marker CA 15-3 in the following: the diagnosis of breast cancer relapse after curative mastectomy, and the differentiation or the value of tumor marker by site of metastases. Materials and Methods: Two hundred two patients (median age 48 years) with breast cancer included in the follow-up after curative mastectomy. The tumor marker CA 15-3 was determined by IRMA (CIS BIO INTERNATIONAL, France). Test values > 30 U/ml were considered elevated (positive). Results: Among 202 patients, recurrent diseases were found in 16 patients. CA 15-3 was elevated in 5 of 16 patients with recurrences. There was no false-positive patient who had elevated CA 15-3. Sensitivity and specificity of CA 15-3 for detection of breast cancer recurrence were 31%, and 100%. CA 15-3 was elevated in all of the 4 patients with liver metastases. CA 15-3 was elevated in none of the patients who relapsed with metastasis to bone-only or contralateral breast-only. Conclusion: The tumor marker CA 15-3 in the detection of breast cancer relapse after curative mastectomy is specific, but not sensitive. However, it is useful to rule out liver metastases of breast cancer, which indicates bad prognosis.

• Journal of Bio-Environment Control
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• v.11 no.3
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• pp.127-132
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• 2002

Enhanced supply of $Ca^{2＋}$ as well as NO$_3$$^{[-10]}$ is known to restrict the uptake of the Na$^{＋}$ and Cl$^{[-10]}$ ion and ameliorate growth under saline conditions. This test was conducted to investigate the ameliorating effects of Ca(NO$_3$)$_2$ or CaCl$_2$ on the growth and yield of NaCl-stressed tomato plants grown in plastic pot filled with soil. All treatments except for the control were supplied with 80 mM NaCl fur two weeks after transporting. The saline solutions with nutrient were supplemented with either 0, 10 or 20 mM Ca(NO$_3$)$_2$ and either 0, 10 or 20 mM CaCl$_2$ during harvesting time from two weeks after transporting. Ca(NO$_3$)$_2$ or CaCl$_2$ application enhanced the growth such as plant height, fresh weight, dry weight, fruit number, and fruit weight, and yield of NaCl-stressed tomato, and also their effects increased greater as concentration of supplemented Ca(NO$_3$)$_2$ or CaCl$_2$increased. Yield increased in 20 mM Ca(NO$_3$)$_2$ compared with the others except fur the control. Photosynthetic rate in Ca treatments was lower than that of the control, but higher than that of NaCl treatment. Leaf chlorophyll content was higher in Ca treatments compared with the others, especially in younger leaf, while that was not affected by concentration of supplemented Ca. Ca(NO$_3$)$_2$ or CaCl$_2$ supply increased the $K^{＋}$ and $C^{2＋}$ concentration of tomato plants, whereas the Na$^{＋}$ transport to the leaves was inhibited. There was a strong increase in the $K^{＋}$/Na$^{＋}$ ratio in plants treated Ca(NO$_3$)$_2$, or CaCl$_2$. Cl$^{[-10]}$ content of plants was decreased by supplemental Ca(NO$_3$)$_2$ but Cl$^{[-10]}$ was increased in plants with CaCl$_2$compared with Ca(NO$_3$)$_2$. N concentration in plants of tomato increased with enhanced Ca(NO$_3$)$_2$ or CaCl$_2$supply, In conclusion, our study confirms the potential of Ca(NO$_3$)$_2$ or CaCl$_2$to alleviate NaCl-induced growth reductions in tomato.

• Journal of Nutrition and Health
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• v.43 no.4
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• pp.351-356
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• 2010

This study was done to evaluate the effect of Ca source using fish (Tilapia mossambica) scales on the bone metabolism. Male Sprague-Dawley rats, 4 weeks of age, were fed low-calcium diet (0.15% Ca) for 2 weeks. The rats on the low-calcium diet were further assigned to one of following three groups for an additional 4 weeks: 1) Ca-depletion group (LoCa) given 0.15% Ca diet ($CaCO_3$), 2) Ca-repletion group (AdCa) given 0.5% Ca diet ($CaCO_3$), 3) Ca-repletion diet (AdFa) received 0.5% Ca diet (Ca source from Tilapia mossambica scales). Serum parathyroid (PTH) and calcitonin showed no differences among experimental groups. Whereas LoCa group elevated the turnover markers, serum ALP and osteocalcin, and urinary deoxypyridinoline (DPD), AdCa and AdFa groups reduced their values. Elevation in the femoral weight, ash and Ca contents was observed in AdCa and AdFa groups. Bone mineral density was increased in AdCa and AdFa groups by 25-26% compared with LoCa group. These data demonstrate that Ca repletion with either Ca source from Tilapia mossambica scales or $CaCO_3$ is similarly effective in the improvement of bone turnover markers and BMD, suggesting the usefulness of Tilapia mossambica scales in the prevention of bone loss compared with $CaCO_3$.

• Journal of the Korean Chemical Society
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• v.43 no.4
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• pp.384-385
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• 1999

Two anhydrous crystal structures of fully dehydrated, $Ca^{2+}$- and $Tl^+$-exchanged zeolite X, TEX>$Ca_{18}Tl_{56}Si_{100}Al_{92}O_{384}($Ca_{18}Tl_{56}$-X;\alpha=24.883(4)\AA)$ and TEX>$Ca_{32}Tl_{28}Si_{100}Al_{92}O_{384}($Ca_{32}Tl_{28}$-X;\alpha=24.973(4)\AA)$ per unit cell, have been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd3 at $21(1)^{\circ}C.$ $Ca_{18}Tl_{56}-X$ was prepared by ion exchange in a flowing stream of 0.045 M aqueous $Ca(NO_3)_2$ and 0.005 M $TlNO_3$. $Ca_{32}Tl_{28}-X$ was prepared similarly using a mixed solution of 0.0495 M $Ca(NO_3)_2$ and 0.0005M $TlNO_3$. Each crystal was then dehydrated at 360 $^{\circ}C$ and $2{\times}10^{-6}$ Torr for 2 days. Their structures were refined to the final error indices, $R_1=0.039\;and\;R_2=0.036$ with 382 reflections for $Ca_{18}Tl_{56}-X$ , and $R_1=0.046\;and\;R_2=0.045$ with 472 reflections for $Ca_{32}Tl_{28}$-X for which $/>3\sigma(I).$ In the structures of dehydrated $Ca_{18}Tl_{56^-}X\;and\;Ca_{32}Tl_{28}$-X, $Ca^{2+}\;and\;Tl^+$ ions are located at six crystallographic sites. Sixteen $Ca^{2+}$ ions fill the octahedral sites I at the centers of double six rings ($Ca_{18}Tl_{56}$-X:Ca-O=2.42(1) and O-Ca-O=93.06(4)$^{\circ}$; $Ca_{32}Tl_{28}$-X Ca-O=2.40(1) $\AA$ and O-Ca-O=93.08(3)$^{\circ}$). In the structure of $Ca_{18}Tl_{56}$-X, another two $Ca^{2+}$ ions occupy site II (Ca-O=2.35(2) $\AA$ and O-Ca-O=111.69(2)$^{\circ}$) and twenty six $Tl^+$ ions occupy site II opposite single six-rings in the supercage; each is 1.493 $\AA$ from the plane of three oxygens $(Tl-O=2.70(8)\AA$ and O-Tl-O=92.33(4)$^{\circ}$). About four $Tl^+$ ions are found at site II',1.695 $\AA$ into sodalite cavity from their three oxygen plane (Tl-O=2.81 (1) and O-Tl-O=87.48(3)). The remaining twenty six $Tl^+$ ions are distributed over site III'(Tl-O=2.82 (1) $\AA$ and Tl-O=2.88(3)$^{\circ}$). In the structure of $Ca_{32}Tl_{28}$-X, sixteen $Ca^{2+}$ ions and fifteen $Tl^+$ ions occupy site III' (Ca-O=2.26(1) $\AA$ and O-Ca-O=119.14(4)$^{\circ}$; Tl-O=2.70(1) $\AA$ and O-Tl-O=92.38$^{\circ}$) and one $Tl^+$ ion occupies site II'. The remaining twelve $Tl^+$ ions are distributed over site III'. It appears that $Ca^{2+}$ ions prefer sites I and II in that order and $Tl^+$ ions occupy the remaining sites.