• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.200.2-200.2
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• 2014

HAP란 Hydroxylapatite의 준말이며 우리말로는 수산화인회석으로도 불린다. 본 실험에서는 다양한 농도의 염기조건(NaOH $10^{-3}$, $10^{-2}$, $10^{-1}$, 1, 10, 30 M)에서 서로 다른 형태의 HAP를 수열합성법을 통해 합성하였다. XRD (X-ray powder diffraction) 로 관찰한 결과 NaOH 농도 $10^{-1}M$ 이상에서부터 HAP가 합성됨을 확인하였다. Transmission and scaning electron microscopy 를 이용하여 HAP의 모양과 표면을 관찰해본 결과, NaOH의 농도가 진해 질수록 육각기둥의 형태에서 사각형으로 변화하였다. 6개의 각각의 HAP의 표면에 Pd (Palladium)을 도입하고 그 양을 정량화 하였다. 합성된 Pd-HAP를 C-C coupling reaction에 이종상 촉매로 사용하였다.

• Journal of Environmental Science International
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• v.11 no.3
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• pp.257-262
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• 2002

The hydroxyapatite(HAp) for the present study was prepared with the wastewater sludge from semiconductor fabrication process and it was crystallized in an electric furnace for 30 min at 90$0^{\circ}C$. The adsorption characteristics of HAp for phosphate ion in aqueous solution has been investigated. The adsorbed ratio of phosphate ion for HAp were investigated according to the reaction time, amount of HAp, concentration of standard solution, pH of solution, and influence of concomitant ions. The amount of adsorbed phosphate ion decreased with the increase of pH due to the mutual electrostatic repulsion between adsorbed phosphate ions and competitive adsorption between phosphate ion and OH- ion in aqueous solution. The maxium amount of the adsorption equilibrium for phosphate ion was about 24 mg/g of HAp. The HAp would likely to be a possible adsorbent for the removal of phosphate ion in the waste water.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.11a
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• pp.71-72
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• 2008

• Journal of the Korean Society of Physical Medicine
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• v.11 no.2
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• pp.53-62
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• 2016

PURPOSE: The purpose of this study was to investigate the effects of a supplementary Ki-hap technique and verbal encouragement on the activation of abdominal muscles during performance of crunch exercise in healthy subjects. METHODS: 93 subjects were randomly allocated to three group, crunch exercise group (CG), crunch exercise with Ki-hap group (CKG), and crunch exercise with Ki-hap and verbal encouragement group (CKVG), with 31 subjects in each group, respectively. The interventions were conducted over three trials in each group, and measurements were performed on each subject by one examiner in three trials. The activation of rectus abdominis (RA), external oblique (EO), and internal oblique (IO) muscles were evaluated using electromyography (EMG) during performance of crunch exercise with non-Ki-hap, Ki-hap and Ki-hap combined with verbal encouragement. RESULTS: Our results showed a significantly greater increase in the EMG patterns of all muscles during performance of crunch exercise in the CKG (p<0.05) compared to the CG and CKVG. The results also showed that there were significantly greater increase in the activation of EO and IO muscles in those of the CKVG (p<0.05) compared with the CG. CONCLUSION: These findings demonstrated that addition of the Ki-hap technique and verbal encouragement during performance of crunch exercise, at the same time, would suggest positive evidence for improving activation of abdominal muscles.

• Journal of the Korean Ceramic Society
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• v.41 no.3
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• pp.259-265
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• 2004

The microstructure of nano-sized hydroxyapatite (HAp) powders coating layer on ZrO$_2$ substrate was investigated, which was formed by plasma spray process. The nano-sized HAp powders were successfully synthesized by precipitation of Ca(NO$_3$)$_2$$.$4H$_2$O and (NH$_4$)$_2$HPO$_4$ solution. The HAp coating layer with thickness of 150∼250 $\mu\textrm{m}$ was free from the cracks at interfaces between the coating and ZrO$_2$ substrate. In the plasma sprayed HAp coating layer, the undesirable phases were not found, while in the HAp coating layer heat-treated at 800$^{\circ}C$, TTCP, and ${\beta}$-TCP phase were detected as well as HAp phase. However, at 900$^{\circ}C$, they were completely disappeared. At 1100$^{\circ}C$, XRD analysis revealed that the coating layer was composed of the highly crystallized HAp.

• Journal of the Korean Ceramic Society
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• v.43 no.1 s.284
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• pp.48-54
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• 2006

Hydroxyapatite $(HAp,\;Ca_{10}(PO_4)_6(OH)_2)$/alumina composites were fabricated with the addition of fluorides, such as $MgF_2$ and $CaF_2$. In this study, the effect of fluorides on the inhibition of phase decomposition and the mechanical properties of HAp was investigated. Due to the higher solubility of F ion in HAp structure, $MgF_2$ additive was more effective compared to $CaF_2$ additive in the lowering decomposition temperature of HAp. Therefore, the dissociation tendency of HAp was fully inhibited below $1400^{\circ}C$. The mechanical properties of HAp composites with $MgF_2$ additive showed higher value (flexural strength: $\~170MPa$, Vickers hardness: $\~7\;GPa$, fracture toughness: $\~1.5\;MPam^{1/2}$) compared to $MgF_2-free$ composites. The linear thermal expansion coefficient of HAp composites with $MgF_2$ showed the value of $16.4\times10^{-6}/^{\circ}C\;at\;20\~400^{\circ}C $.

• Journal of the Korean Ceramic Society
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• v.49 no.1
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• pp.72-77
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• 2012

In the preparation of a hydroxyapatite [HAp]/gelatin [GEL] nanocomposite, the GEL matrix in aqueous solution of $H_3PO_4$ was modified by the introduction of aspartic acid [Asp], asparagine [Asn], and glycine [Gly]. The addition of Asp, Asn and Gly greatly affected the slurry formation of HAp/GEL nanocomposite and the resulting dry body showed variations in toughness with the addition of the different amino acids. The introduction of Asn into HAp/GEL nanocomposite was effective for producing the organic-inorganic interaction between HAp and GEL, and caused the increase of toughness. The formation reaction of the modified HAP/GEL nanocomposites was investigated by using XRD and FT-IR. The organic-organic interaction between the GEL matrix and the additives of Asp, Asn and Gly was confirmed from FT-IR analysis, and the organic-inorganic interaction between HAp nanocrystallites and the modified GEL matrix was also discussed, using FT-IR spectra patterns. Nanocrystallites of HAp were covalently bound with the GEL macromolecules and differently influenced by the modification species of Asp, Asn, and Gly.

• Applied Chemistry for Engineering
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• v.27 no.6
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• pp.669-671
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• 2016

Hydroxyapatite (HAP) was prepared by a hydrothermal synthesis method and also silver was introduced on the surface of HAP through an ion exchange reaction. The crystal phase and morphology of HAP were then evaluated by X-ray diffraction (XRD) and transmission electron microscopy (TEM). In addition, the absorption property of HAP was characterized by diffuse reflectance UV-Vis spectroscopy. The presence of silver nanoparticles on the surface of HAP was also verified by XRD and TEM analysis. Particularly, the silver doped HAP showed an enhanced absorption property in UV-Vis region compared to that of the pristine HAP.

• Journal of Haehwa Medicine
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• v.14 no.1
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• pp.167-177
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• 2005

In oriental medicine, Ostericum koreanum Radix & Aralia contientalis Radix are frequently used materials for strenthing lumbar and knees. Bang-Yak-Hap-Pyun(方藥合編) is widely used for clinical herbal prescription book. In Bang-Yak-Hap-Pyun, Ostericum koreanum Radix is used 1.2g~6g. and Aralia contientalis Radix is used 1.6g~4.8g. The most important fact is that the prescription used Ostericum koreanum Radix & Aralia contientalis Radix at the same time is 11. The number of prescription Ostericum koreanum Radix & Aralia contientalis Radix in Bang-Yak-Hap-Pyun is total 41. 5 in sang-tong(上統), 22 in jung-tong(中統), 14 in ha-tong(下統). The group of mostly used disease is about low back pain, knee pain, C.V.A., facail palsy, commom cold, numbness. The ratio of Ostericum koreanum Radix in Bang-Yak-Hap-Pyun is 3.03%~15.63%. And the ratio of Aralia contientalis Radix is 3.57%~12.00%. The mostly quoted medical literature what prescription included Ostericum koreanum Radix & Aralia contientalis Radix in Bang-Yak-Hap-Pyun is Dong-Yi-Bo-Gam. Man-Byeong-Hoi-Choon, and Hwa-Je-Gook-Bang.

• Journal of Haehwa Medicine
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• v.14 no.1
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• pp.179-186
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• 2005

In oriental medicine, Achyranthis Bidentatae Radix & Dipsaci Radix are frequently used materials for strenthing lumbar and knees. Bang-Yak-Hap-Pyun(方藥合編) is widely used for clinical herbal prescription book. In Bang-Yak-Hap-Pyun, Achyranthis Bidentatae Radix is used 1g~8g. and Dipsaci Radix is used 1g~3.2g. The most important fact is that the prescription used chyranthis Bidentatae Radix & Dipsaci Radix at the same time is only 1(Man-Geum-Tang-the ratio of Achyranthis Bidentatae Radix & Dipsaci Radix is 1:1). The number of prescription Achyranthis Bidentatae Radix & Dipsaci Radix in Bang-Yak-Hap-Pyun is total 19. 14 in sang-tong(上統), 2 in jung-tong(中統), 3 in ha-tong(下統). The group of mostly used disease is about lumbar and knees. The ratio of Achyranthis Bidentatae Radix in Bang-Yak-Hap-Pyun is 3.88%~25%. And the ratio of Dipsaci Radix is 8.33%~12.5%. The mostly quoted medical literature what prescription included Achyranthis Bidentatae Radix & Dipsaci Radix in Bang-Yak-Hap-Pyun is Dong-Yi-Bo-Gam and Gyung-Ak-Jun-Su Sin-Bang-Pal-Jin.