• Resources Recycling
• /
• v.3 no.3
• /
• pp.32-49
• /
• 1994

Hydration process is one of the basic carbonation system. Limestone sludge produced in Pohang Iron & Steel Co., Ltd. We tested for identify of hydration characteristics. The result obtained in this study can be summarized as follows; 1. The classify of limestone sludge is type of ground calcium carbonate(-3mm+325mesh)and the major mineral of calcite, and further more high grade(CaO 51%), fine powder(15~22$\mu\textrm{m}$). 2. Limestone sludge mixed two process sludge, first one is washing process sludge and the other one is wet collect kiln dust. The composition rate is about 8:2. Wet collect kiln dust is major mineral of calcite, too. But the sludge is assumed to one by quick lime, slaked lime and unreacted natural limestone. So, the ideal process is dividing of the washing process sludge and wet collect kiln dust. 3. We manufactured of slaked lime from limestone sludge. To investigate the effect of hydration reactor, the experiments was done with various reactor type as magnetic stirrer, shaking incubator and ultrasonic vibration reactor, respectively. Generally, ultrasonic vibration reactor is excellent hydration for limestone sludge and produced very fine slaked lime powder with ideal distribution. 4. The optimum condition is 10% pulp density, when the manufacture of fine slaked lime powder by ultrasonic vibration reactor. And hydration times to compare the results of the study with ultrasonic vibration reactor of generalized most short time(5~10 min). 5. Finally, the dispersive characteristics of slaked lime powder measured 1~5 $\mu\textrm{m}$ from limestone sludge were compared with those of natural limestone ones(10~20$\mu\textrm{m}$), in order to check applicability of slaked lime with hydration process from limestone sludge.

• Journal of radiological science and technology
• /
• v.39 no.1
• /
• pp.13-17
• /
• 2016

In this study, standard model of medical radiation dosage quality control system will be suggested and the useful of this system in clinical field will be reviewed. Radiation dosage information of modalities are gathered from digital imaging and communications in medicine(DICOM) standard data(such as DICOM dose SR and DICOM header) and stored in database. One CT scan, two digital radiography modalities and two mammography modalities in one health promotion center in Seoul are used to derive clinical data for one month. After 1 months research with 703 CT scans, the study shows CT $357.9mGy{\cdot}cm$ in abdomen and pelvic CT, $572.4mGy{\cdot}cm$ in brain without CT, $55.9mGy{\cdot}cm$ in calcium score/heart CT, screening CT at $54mGy{\cdot}cm$ in chest screening CT(low dose screening CT scan), $284.99mGy{\cdot}cm$ in C-spine CT and $341.85mGy{\cdot}cm$ in L-spine CT as health promotion center reference level of each exam. And with 1955 digital radiography cases, it shows $274.0mGy{\cdot}cm2$ and for mammography 6.09 mGy is shown based on 536 cases. The use of medical radiation shall comply with the principles of justification and optimization. This quality management of medical radiation exposure must be performed in order to follow the principle. And the procedure to reduce the radiation exposure of patients and staff can be achieved through this. The results of this study can be applied as a useful tool to perform the quality control of medical radiation exposure.

• Journal of Soil and Groundwater Environment
• /
• v.9 no.4
• /
• pp.15-23
• /
• 2004

Deicer operations provide traffic safety during winter driving conditions in urban areas. Using large quantities of de-icing chemicals (i.e., $CaCl_2$ and NaCl) can cause serious environmental problems and may change behaviors of heavy metals in roadside sediments, resulting in an increase in mobilization of heavy metals due to complexation of heavy metals with chloride ions. To examine effect of de-icing salt concentration on the leaching behaviors and mobility of heavy metals (cadmium, zinc, copper, lead, arsenic, nickel, chromium, cobalt, manganese, and iron), leaching experiments were conducted on roadside sediments collected from Seoul city using de-icing salt solutions having various concentrations (0.01-5.0M). Results indicate that zinc, copper, and manganese in roadside sediments were easily mobilized, whereas chromium and cobalt remain strongly fixed. The zinc, copper and manganese concentrations measured in the leaching experiments were relatively high. De-icing salts can cause a decrease in partitioning between adsorbed (or precipitated) and dissolved metals, resulting in an increase in concentrations of dissolved metals in salt laden snowmelt. As a result, run-off water quality can be degraded. The de-icing salt applied on the road surface also lead to infiltration and contamination of heavy metal to groundwater.

• Journal of Soil and Groundwater Environment
• /
• v.16 no.1
• /
• pp.82-90
• /
• 2011

Reactive reductants of cement/Fe(II) systems in dechlorinating chlorinated hydrocarbons have not been identified. The previous studies showed that a hematite/CaO/Fe(II) system had TCE degradation characteristics similar to those of cement/Fe(II) systems with regard to degradation kinetics and that lime (CaO) plays an important role in enhancing the reactivity for TCE dechlorination. The current study shows identified the formation of gypsum ($CaSO_4$) in the hematite/CaO/$FeSO_4$ system through the XRD analysis. The amounts of the gypsum increased with increment of the initial CaO dose. However, when CaO in the hematite/CaO/$FeSO_4$ system was replaced with gypsum, TCE degradation was not observed. Ca-removed Portland cement extracts (CPCX) in combination with $FeSO_4(CPCX/FeSO_4)$ showed no TCE degradation. On the other hands, the Portland cement extracts (PCX) in the presence of $FeSO_4(PCX/FeSO_4)$ and CPCX/CaO/$FeSO_4$ systems degraded 0.2 mM TCE within 5 days, indicating that CaO also played an important role dechlorination reactions in the systems. The pseudo-first-order rate constants (k) of the CPCX/CaO/$FeSO_4$ systems were 0.20, 0.24, and 0.72 $day^{-1}$, when the CaO dosages were 25, 50 and 75 g/L, respectively. The XRD analyses showed identified the common peaks having the d-values of 3.02, 2.27, and 1.87 in the reaction systems that showed TCE degradation. However, it was not possible to clearly identify the crystalline minerals having the three peaks from the references in JCPDS cards. This study reveals that the reactive agents in the cement/Fe(II) and the hematite/Fe(II) systems are likely to be those containing CaO and Fe(II).

• Polymer(Korea)
• /
• v.35 no.4
• /
• pp.363-369
• /
• 2011

To study the effect of incorporation of a surface crosslinking layer on a crosslinked poly (sodium acrylate) (cPSA) absorbent with ethylene glycol dimethacrylate CEGDMA), we synthesized several surface crosslinked cPSAs with EGDMA by an inverse emulsion polymerization method to delay the absorption of excess water in concrete, Liquid paraffin was used as a continuous phase. cPSA was synthesized with acrylic acid (AA) neutralized with aqueous 8 M sodium hydroxide solution as a monomer, N,N-methylene bisacrylamide (MBA) as crosslinking agent and ammonium persulfate (APS) and sodium metabisulfite (SMBS) as a redox initiator system by inverse emulsion polymerization. FTIR spectroscopy was used to characterize $Ca^{2+}$ ion interaction with cPSA and cPSA-EGDMAs. The swelling ratios of synthesized absorbents were evaluated from the absorption in deionized water, cement saturated aqueous solution and aqueous solution of calcium hydroxide (pH 12). Equilibrium swelling times for cPSA and surface crosslinked cPSA with EGDMA were 2 and 3 hrs, respectively. We also observed an increase in setting time of the cement and an increase in the compressive strength of mortar by addition of the synthesized cPSA-EGDMA.

• The Journal of Korean Obstetrics and Gynecology
• /
• v.18 no.1
• /
• pp.55-63
• /
• 2005

Purpose : 자하거(Hominis Placenta; HP)는 건강한 사람의 태반을 홍제(烘製)하여 건조한 것으로 한의학에서는 기혈(氣血)을 대보(大補)하고 신정(腎精)을 보익(補益)시켜 구병(久病)으로 인한 신체허약(身體虛弱)이나 혹은 체질허약(體質虛弱)과 혈기부족(氣血不足) 및 신허정휴(腎虛精虧) 등 등(證)을 치료(治療)하는데 단미(單味) 또는 복방(複方)에 배오(配伍)하여 쓰여왔다. 또한 자하거는 면역학적으로 골대사 활성이 있는 것으로 알려져 있어 본 연구에서는 자하거의 항골다공증 활성을 분자세포생물학적으로 검정하고자 하였다. Methods : Osteoblast cells에서 자하거가 COX-2 mRNA의 발현과 $PGE_2$ 생합성을 억제시키는지를 관찰하기 위해 먼저 TNF-${\alpha}$, IL-${\beta}$ 와 IL-6를 처리한 후 $PGE_2$의 생합성과 더불어 COX-2 mRNA의 발현을 확인하였다. 그 후 TGF-${\beta}$, 자하거(紫河車)와 이 둘의 조합인 자하거+TGF-${\beta}$가 COX-2 mRNA 발현과 $PGE_2$ 생합성을 저해시키는지 관찰하였다. 또한 자하거가 IL-1${\beta}$로 유발된 흰쥐의 과칼슘혈증을 감소시키는지를 확인하였다. Results : IL-6, IL-1${\beta}$와 TNF-${\alpha}$를 동시에 처리하면 이것을 단독으로 처리한 것과 비교해 볼 때 $PGE_2$의 생합성과 더불어 COX-2 mRNA의 수치가 상승작용을 일으키며 증가하였다. TGF-${\beta}$, 자하거와 이 둘의 조합인 자하거+TGF-${\beta}$은 COX-2 mRNA 발현, $PGE_2$ 생합성 및 골재흡수를 감소시켰다. 자하거(紫河車)는 IL-1${\beta}$, TNF-${\alpha}$와 IL-6 각각 또는 이들의 조합으로 인해 증가하는 COX-2 mRNA 발현과 $PGE_2$ 생성을 감소시키는 반면 COX-1 mRNA 발현에는 유의성 있는 영향을 미치지 않았다. 한편 자하거는 농도의존적으로 IL-1${\beta}$로 유발된 흰쥐의 과칼슘혈증을 감소시켰다. 이러한 결과는 흰쥐의 두개골 골아세포에서 $PGE_2$ 생산에 대한 IL-${\beta}$, TNF-${\alpha}$, IL-6의 상승작용이 COX-2의 유전자 발현 증가에 기인함을 보여주었다. Conclusions : 이러한 결과들로부터 자하거가 골대사과정중 골재흡수를 억제하는데 효과적임을 밝히게 되었으며, 자하거의 골다공증의 억제기전이 골재흡수관련 단백질들의 전사조절에 있음을 최초로 해명하게 되었다.

• Korean Journal of Pharmacognosy
• /
• v.46 no.2
• /
• pp.167-172
• /
• 2015

Aleurone layer of Black rice (Oryza sativa L.) is enriched with anthocyanin that could increase bone density. This study was conducted to investigate the osteoporosis-preventing effects of the aleurone layer extract (BRE) on bone loss of ovariectomized (OVX) rats. OVX (or sham-operated) rats were assigned to three groups (n=8 per group): sham operated group (Sham); OVX control group (OVX); OVX-BRE group, OVX rats treated with BRE at 90 mg/kg B.W. The deionized water alone or deionized water with BRE was orally administrated to Sham, OVX or OVX-BRE groups, respectively for 12 weeks. High fat diet with 45 kcal% fat and water were fed to all rats ad libitum. Body weight was significantly decreased in the OVXBRE group compared to the OVX group (p<0.05). The bone mineral density and bone length of tibia were significantly higher in the OVX-BRE group compared to the OVX group and breaking force was significantly higher for the both tibia and femur bones. Serum estradiol concentration and calcium concentration of femur were higher in the OVX-BRE group than those of OVX group. However, serum alkaline phosphatase activity and parathyroid hormone concentration were decreased in the OVXBRE group compared to the OVX group. The results suggest that aleurone layer of Black rice is a potentially useful ingredient to protect against estrogen deficiency or menopause related osteoporosis.

• Archives of Plastic Surgery
• /
• v.37 no.4
• /
• pp.415-420
• /
• 2010

Purpose: Heterotopic calcification is a pathological event in which deposits of calcium salts build up, usually in the joint area or soft tissues. It can occur under many conditions and in some rare cases may develop in burn scars. In particular, ulcerations in burn scars accompanied by heterotopic calcification are difficult to treat through conservative treatment. This study reports methods for accurate diagnosis and adequate treatment of ulceration in burn scars accompanied by heterotopic calcification. Methods: Fourteen patients who visited our hospital from March 2008 to January 2010 were subjected to this study. Their sex, age, modes of burn, degree, TBSA (%), ulcerated area, the time of occurrence of the ulcerations in the burn scars were investigated. In addition, radiological examination and biopsy was performed to diagnose heterotopic calcification. Results: Among the 14 cases, 6 were male and 8 were female. The average age of the patients was 48.2 (27 - 69 yrs). As for the mode of burn, 11 were flame burns and 3 were scalding burns. The average time of occurrence of the ulcerations in the burn scars was 4.5 months. The ulcerated areas were situated in the legs in 12 cases, arms in 1 case, and torso in 1 case. The diagnosis was confirmed through X-ray and biopsy, and skin graft was performed after wide excision. Conclusion: Diagnosis of the ulceration in burn scars accompanied by heterotopic calcification is possible through radiological and pathologic studies. Surgical treatment is the most reliable method of treatment, and we chose to perform skin graft after wide excision. Also, we learned that the complete removal of the calcified tissue and the inflammatory fibrotic tissues is crucial in preventing recurrence. Also, in contrast to Marjolin's ulcer, heterotopic calcification had a small size, little or no granulation tissue, and lacked fungating type ulceration. Therefore, favorable prognosis could be achieved through adequate treatment.

• Korean Journal of Poultry Science
• /
• v.30 no.2
• /
• pp.101-106
• /
• 2003

In order to study the optimum daily protein allowance for broiler breeders of 24 to 64 weeks of age on a control-fed basis, an experiment was carried out with 400 hens of Arbor Acres strain. Four levels of protein allowances were used to supply 18 to 24g of protein per day in 2g increments. As the age of hens increased, a same stepwise increase and decrease in daily energy allotment was used in all treatments. Same amount of calcium, phosphorus, methionine and lysine were supplied in all treatments and throughout laying period. Hen-day egg production was highest in hens receiving 20g protein per day(p<0.05), but there was no significant difference among those fed daily protein ranging 18 to 22g, and increasing the daily protein allotment up to 24g resulted in a significant decrease(p<0.05). Average egg weight showed a trend to increase as the daily protein allowance increase(p<0.05), but no significant difference was found among the hens fed daily protein 20 to 24g. Feed and ME conversion was superior in hens receiving 20g daily protein(p<0.05). CP conversion was increased as the daily protein allowance increase(p<0.05), but there was no significant difference between hens receiving 18 and 20g daily protein. Feed cost required per egg or per kg egg was lowest in hens fed 20g daily protein. It could be concluded that the optimum daily protein allowance was 20g in all performances.

• Korean Journal of Poultry Science
• /
• v.30 no.2
• /
• pp.107-112
• /
• 2003

This experiment was conducted to study the optimum energy feeding system for broiler breeders peaked in summer season with 400 caged hens of Ross strain. Four of energy supply series which were different in daily energy allotment during laying period were employed for 40 weeks from 24 to 64 weeks of age. All experimental diets were formulated to contain 2,750 kcal ME/kg with adjustments made in total feed allotment to provide the desired energy levels. Total consumption of the feed would provide 20 grams of protein, 4 grams of calcium and 0.35 grams of available phosphorus. There were no significant difference in hen-day egg production and average egg weight among the series of energy supply, but egg production showed a trend to decline as the level of energy allotment increased. Feed, ME and CP conversion and feed cost required per egg or per kg egg were significantly increased as the level of energy allotment increased(p<0.05). It was concluded that the Treatment 1, which supplied 280kcal ME per day at the age of 24 weeks and then increased the energy supply up to 400kcal ME per day at the peak period of 30∼34 weeks of age, was superior in all production parameters.