• Title/Summary/Keyword: calcium.

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Effect of reaction temperature on the particle size and crystal shape of precipitated calcium carbonate (반응온도가 침강성탄산칼슘의 입도 및 형상에 미치는 영향)

  • 송영준;박찬훈;조동성
    • Resources Recycling
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    • v.4 no.1
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    • pp.38-45
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    • 1995
  • The objective of this study was to investigate the effect of temperature on the formation of CaCO, polymorphs(i.e.,calcite, aragonite, vaterite) and on the crystal shape of CaCO,.The reaction systems were rnvestigated at the temperature range of 2.0%-85.3r, at the fixed cmditions ofconcentration and pressure, 2X10-' M, atomospheric pressure, respectively.The reaction systems studied include a Ca(HCO.,),-Air bubble, O Ca(OH)s-CO,, @ Ca(OH),-H,CO, ,Ca(OH1,-Na>CO,, O Ca(OH),-K,CO,, @ Ca(OH),-(NH,),CO,, D CaC1,-Na,CO,, CaC1,-K3C03, 8 CaC1,-(NH,,),CO,, 0 Ca(N0,X-Na,CO,, 03 Ca(N0,X-QCO,. 0 Ca(NO,),-(NH,XCO,. The results obtained are summarizedas follows:Calcite is formed at the temperature range of 2t-80"C and the highest calcite yield was obtained at 30%.Aragonite begins to be formed at the temperature range of 41.0%-53.0%. and the higher temperature is thehigher yield is obtained. pH of the reaction system affect the yield of aragonite, and the yield reaches the highestpercentage at the pH range of 10.0-11.0, and at the conditions of pH 12.3 or over, aragonite is scarcely formed.Vaterlle is fnrmed at the temperature range of 40.0% or less, and transites utterly to calcite within 10-60mmutes in the case of bemg residenced in mother liqmd which C1 is not contained, and within 140hours inthe case of containing CI-.s in the case of containing CI-.

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High School Students' Preferences and Food Intake on Menu Items Offered by School Foodservice in Daegu (대구지역 학교급식 식단에 대한 고등학생의 기호도와 섭취율)

  • Kim, So-Hee;Cha, Myeong-Hwa;Kim, Yoo-Kyeong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.7
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    • pp.945-954
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    • 2006
  • The purpose of this study is to present basic data for an improvement of school foodservice by indentifying students' preference level for school meal menu and assessing students' nutrition intake. The subjects participated in this study were 544 high school students on 1st grade served by self-operated school foodservice in Daegu. The frequency analysis, t-test analysis, and correlation analysis were carried out for the data analysis using SPSS 12.0 program. Based on the results toward students' preference and serving frequency, the most frequently offered food was soup sorts and then followed by the categories of boiled rice, kimchi, broiled food and hard-boiled food. Boiled rice, rice with assorted vegetables, mandu soup, salad and braised beef rib were highly preferred to the students. Male students scored higher preference to the menu related with meats than female students. However, the students' preference and serving frequency on the menu were not correlated significantly in this study. A substantial correlation was found between the degree of preference and the rate of intake (p<0.01). It would be generalized that preferences to menu items strongly sffected the level of intake by students. The nutrient analysis of food intake revealed that both male and female students were not consuming sufficient level of calorie, calcium and vitamin $B_2$. In conclusion, the results indicate that the students' preference is a very important variable influencing the consumption level of meal as well as balanced nutrient intake by students served in school foodservice. Menu planning should be integrated into school foodservice management for quality control. As limited control of the menu may also negatively influence on the food leftovers and ecological issues, professionals related to the school foodservice including administers, educators and dieticians need to check up the students' preference regularly and reflect their perception on the menu planning to improve the quality of school foodservice. The nutrient intake currently provided through school foodservice should be also assessed more thoroughly. These data could be incorporated into continuous quality improvement and strategic planning in school foodservice.

Effects of Dietary Seaweed on Blood Glucose, Lipid and Glutathione Enzymes in Streptozotocin-Induced Diabetic Rats (미역첨가 식이가 당뇨 유발쥐의 혈청지질과 혈당 및 항산화 효소에 미치는 영향)

  • 조영자;방미애
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.6
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    • pp.987-994
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    • 2004
  • The purpose of this study was to investigate the effect of dietary seaweed in diabetic rats treated with streptozotocin (STZ) for 7 weeks. The rats (Sprague-Dawley male rats, 180∼200 g) were divided into 4 groups : normal rats fed control diet (C), diabetic rats fed control diet (CD), normal rats fed seaweed diet (M), and diabetic rats fed seaweed diet (MD). Diabetes was induced by single injection of streptozotocin (60 mg/kg, i.p.). Urinary levels of calcium and uric acid, and blood levels of hemoglobin, total cholesterol and low density lipoprotein (LDL)-cholesterol were not significantly different among groups. But high density lipoprotein (HDL)- cholesterol of M and MD groups were higher than that of C and CD groups. Activity of hepatic microsomal G6Pase was significantly (p<0.05) lower in C and M groups than that of CD and MD groups. Hepatic glutathione S-transferase (GST) of M, CD and MD groups were significantly lower than C group (p<0.05), glutathione peroxidase (GPX) of C, M and MD groups were higher than CD group. In conclusion, dietary seaweed may improve blood lipid profiles and GSH-related enzymes in STZ-induced diabetic rats.

Effects of acid-treatment conditions on the surface properties of the RBM treated titanium implants (산-처리 조건이 RBM처리한 티타늄 임플란트의 표면 특성에 주는 영향)

  • Lee, Han-Ah;Seok, Soohwang;Lee, Sang-Hyeok;Lim, Bum-Soon
    • Korean Journal of Dental Materials
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    • v.45 no.4
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    • pp.257-274
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    • 2018
  • The purpose of this study was to evaluate the effect of acid-treatment conditions on the surface properties of the RBM (Resorbable Blast Media) treated titanium. Disk typed cp-titanium specimens were prepared and RBM treatments was performed with calcium phosphate ceramic powder. Acid solution was mixed using HCl, $H_2SO_4$ and deionized water with 4 different volume fraction. The RBM treated titanium was acid treated with different acid solutions at 3 different temperatures and for 3 different periods. After acid-treatments, samples were cleaned with 1 % Solujet solution for 30 min and deionized water for 30 min using ultrasonic cleanser, then dried in the electrical oven ($37^{\circ}C$). Weight of samples before and after acid-treatment were measured using electric balance. Surface roughness was estimated using a confocal laser scanning microscopy, crystal phase in the surface of sample was analyzed using X-ray diffractometer. Surface morphology and components were evaluated using Scanning Electron Microscope (SEM) with Energy Dispersive X-ray spectroscopy (EDX) and X-ray Photoemission Spectroscopy (XPS). Values of the weight changes and surface roughness were statistically analyzed using Tukey-multiple comparison test (p=0.05). Weight change after acid treatments were significantly increased with increasing the concentration of $H_2SO_4$ and temperature of acid-solution. Acid-treatment conditions (concentration of $H_2SO_4$, temperature and time) did not produce consistent effects on the surface roughness, it showed the scattered results. From XRD analysis, formation of titanium hydrides in the titanium surface were observed in all specimens treated with acid-solutions. From XPS analysis, thin titanium oxide layer in the acid-treated specimens could be evaluated. Acid solution with $90^{\circ}C$ showed the strong effect on the titanium surface, it should be treated with caution to avoid the over-etching process.

Manufacturing and Characteristics of Fruit Wine from Acanthapanax sessiliflorus (오가피 열매 발효주의 제조 및 특성)

  • Choi, Jae-Myoung;Kim, Kwang-Yup;Lee, Sang-Hwa;Ahn, Jun-Bae
    • Food Engineering Progress
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    • v.14 no.1
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    • pp.1-6
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    • 2010
  • Fruit wine from Acanthopanax sessiliflorus(A. sessiliflorus) including many pharmacological components was manufactured and its functional properties were investigated. The fruit part of A. sessiliflorus contained 75.74${\pm}$0.49%(w/w) moisture, 12.51${\pm}$1.23%(w/w) crude protein, 4.20${\pm}$0.51.%(w/w) crude fat and 5.21${\pm}$1.64%(w/w) crude ash. Minerals of fruit were potassium(12.94${\pm}$0.08 mg/g), calcium(1.53${\pm}$0.06 mg/g) and magnesium(1.12${\pm}$0.05 mg/g). Initial soluble solid and fermentation temperature were 24-30$^{\circ}$Brix and 20${^{\circ}C}$ for manufacturing fruit wine from A. sessiliflorus. When initial soluble solid of a must was adjusted to more than 30$^{\circ}$Brix, ethanol production was suppressed slightly. The polyphenol content of the fruit wine fermented at 20${^{\circ}C}$(125.24${\pm}$1.86 mg/mL) was higher than those at 25${^{\circ}C}$(99.69${\pm}$2.11 mg/mL) and 30${^{\circ}C}$(95.55${\pm}$1.54 mg/mL). Electron donating activities of wines fermented at 20, 25 and 30${^{\circ}C}$ were 85.9${\pm}$2.3, 55.7${\pm}$2.5 and 55.2${\pm}$3.4%, respectively. The content of eleutheroside B increased up to 146.58${\pm}$4.10 $\mu$g/mL during fermentation. There was no significant effect of fermentation temperature on eleutheroside B content. The fruit part of A. sessiliflorus can be used as a valuable resource for development of nutraceutical foods.

Breeding of Oriental Lily 'Pacific Wave' with Upward-facing and White Petals (상향 개화형 백색 오리엔탈나리 'Pacific Wave' 육성)

  • Rhee, Hye Kyung;Cho, Hae Ryong;Lim, Jin Hee;Kim, Mi Seon;Park, Sang Kun;Shin, Hak Ki;Joung, Hyang Young;Yae, Byeong Woo
    • FLOWER RESEARCH JOURNAL
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    • v.16 no.4
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    • pp.299-303
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    • 2008
  • An Oriental lily cultivar 'Pacific Wave' was released in 2007 at National Institute of Horticultural and Herbal Science, Rural Development Administration (RDA), Suwon, Korea. The crossing was made in 1999 between Oriental lily 'Simplon', an outward-facing and white colored cultivar, and 'Spinoza', pink colored cultivar. The first selection was done in 2003 with a line of 'O-03-16'. Multiplication and bulb growth, and performance test was conducted from 2004 to 2006. This selection was later on given as 'Pacific Wave' in 2007 at NHRI. Flowering time of 'Pacific Wave' in plastics house culture is mid June and grows average 115 cm. Flowers are upward-facing with 20.1 cm in diameter and white with yellow centered (RHS W155C + Y9A). Mean petal length and width is 12.2 cm and 4.2 cm, respectively. Leaves are 12.3 cm long, 2.9 cm wide. The throat color is green. It shows gray and purple stigma, and red brown pollen. The weight and size of bulb is 82.5 g and 19.6 cm, respectively. Year-round flowering can be by storing the bulb under -1 to $-2^{\circ}C$ conditions. It is necessary to add calcium to the fertilizer or remove side scales to prevent leaf scorch. It is needed to control Botrytis disease in summer wet season.

Effect of Application Rate of a Controlled Release Fertilizer on the Changes in Medium EC and Growth of Subirrigated Vinca and Salvia (저면관수 재배에서 완효성 비료의 양이 배지의 EC 및 일일초와 살비아의 생장에 미치는 영향)

  • Kang, Jong Goo;Lee, In Ho
    • FLOWER RESEARCH JOURNAL
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    • v.16 no.2
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    • pp.112-117
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    • 2008
  • Plug seedlings of vinca (Catharanthus roseus L. 'Pacifica Punch') and salvia (Salvia splendens F. Sellow ex Roem & Schult 'Maestro') were transplanted into square plastic pots (145 mL volume) filled with a soilless growing medium. To determine the effect of application rate on the growing medium EC and growth of plants, 0, 0.5, 1.0, 1.5, 2.0 and 4.0 g per pot of a controlled release fertilizer (14-14-14 Osmocote, 14N-6.2P-11.6K) were mixed with the growing medium. Plants were subirrigated daily with tap water. In both vinca and salvia, growing medium EC increased as application rate was elevated. Growing medium EC was relatively constant over a whole crop period when the application rate was less than 1.5 g per pot, while it decreased throughout the experiment at higher application rates such as 2.0 to 4.0g per pot in both species. The greatest leaf area, plant height, and shoot dry weight of vinca were obtained when plants were fertilized with 2.0 to 4.0 g per pot of the fertilizer, resulting in a growing medium EC of $1.0{\sim}1.7dS{\cdot}m^{-1}$ throughout the experiment. Leaf area, shoot dry weight, and chlorophyll content of salvia increased with elevated application rates. Leaf area, shoot dry weight, and chlorophyll content of salvia were the greatest when plants were fertilized with 4.0 g per pot, resulting in growing medium EC of $1.0{\sim}4.0dS{\cdot}m^{-1}$ throughout the experiment. Plant height of salvia was the greatest when plants were fertilized with 2.0 to 4.0g per pot. Concentrations of nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg), and sulfur (S) in the shoots of vinca increased, while concentration of calcium (Ca) decreased with elevated application rates. Concentrations of boron (B) and manganese (Mn) in the shoots of vinca increased as the application rate decreased.

Reduction of Stem Inside-cavity and Improvement of Flower Quality in Chrysanthemum 'Baekma' by pH Stabilization and Foliar Spray of Ethephon (양액 pH 안정화와 에세폰 살포에 의한 국화 '백마'의 줄기동공 경감과 절화품질 향상)

  • Hwang, In Taek;Cho, Kyung Chul;Kim, Hee Gon;Ki, Gwang Yeon;Yoon, Bong Ki;Choi, Kyung Ju;Lim, Jin Hee;Choi, Sung Ryul;Shin, Hak Ki
    • FLOWER RESEARCH JOURNAL
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    • v.18 no.4
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    • pp.238-243
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    • 2010
  • This study was conducted to investigate effects of nutrient solution pH control agent and foliar spray of ethephon on the reduction of stem inside-cavity and improvement of flower quality in chrysanthemum 'Baekma'. Changes of pH in nutrient solution as affected by the kind of pH control agent showed more settled pattern in the plot of KOH treatment than in others. Plant growth and development such as cut flower length, leaf numbers, cut flower weight and petal number were the greatest in the plot of KOH. However, the size and area of stem cavity was large in KOH rather than $KHCO_3$. As changes in the absorbing patterns of mineral elements as affected by nutrient solution pH control agent in closed system, contents of total nitrate, phosphorus, potassium and calcium by $KHCO_3$ was absorbed into the plant less than KOH, so that it remained a lot of mineral element residues rather than KOH in closed system. Plant growth as affected by the foliar spray of ethephon showed growth retardation effect in the plot of solution diluted to 1 : 500 and growth promotion effect in the plot of solution diluted to 1 : 1,000 or 1 : 2,000. The number of petals was the best in the plot of foliar spray of ethephon solution diluted to 1 : 1,000 before flowering at 45 days showing 331 petals compared to control showing 302 petals. The size and area of stem cavity as affected the foliar spray of ethephon was smaller 1 mm and 7%, respectively, in the plot of solution diluted to 1 : 2,000 before flowering at 30 days than in control. Therefore, treating pH stabilization using KOH after floral initiation stage with the foliar spray of ethephon solution diluted to 1 : 2,000 before flowering at 30 days would help to reduce stem cavity size and improve flower quality in hydroponically grown chrysanthemum 'Baekma'.

Pseudo Image Composition and Sensor Models Analysis of SPOT Satellite Imagery for Inaccessible Area (비접근 지역에 대한 SPOT 위성영상의 Pseudo영상 구성 및 센서모델 분석)

  • 방기인;조우석
    • Korean Journal of Remote Sensing
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    • v.17 no.1
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    • pp.33-44
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    • 2001
  • The paper presents several satellite models and satellite image decomposition methods for inaccessible area where ground control points can hardly acquired in conventional ways. First, 10 different satellite sensor models, which were extended from collinearity condition equations, were developed and then behavior of each sensor model was investigated. Secondly, satellite images were decomposed and also pseudo images were generated. The satellite sensor model extended from collinearity equations was represented by the six exterior orientation parameters in $1^{st}$, $2^{nd}$ and $3^{rd}$ order function of satellite image row. Among them, the rotational angle parameters such as $\omega$(omega) and $\Phi$(phi) correlated highly with positional parameters could be assigned to constant values. For inaccessible area, satellite images were decomposed, which means that two consecutive images were combined as one image, The combined image consists of one satellite image with ground control points and the other without ground control points. In addition, a pseudo image which is an imaginary image, was prepared from one satellite image with ground control points and the other without ground control points. In other words, the pseudo image is an arbitrary image bridging two consecutive images. For the experiments, SPOT satellite images exposed to the similar area in different pass were used. Conclusively, it was found that 10 different satellite sensor models and 5 different decomposed methods delivered different levels of accuracy. Among them, the satellite camera model with 1st order function of image row for positional orientation parameters and rotational angle parameter of kappa, and constant rotational angle parameter omega and phi provided the best 60m maximum error at check point with pseudo images arrangement.

Comparison of the Quality Characteristics of Radish by Soaking Using Sun-dried Salt and Leuconostoc starter (무 절임 제조 시 천일염과 스타터 첨가에 따른 품질특성 비교)

  • Na, Jong-Min;Jin, Yong-Xie;Kim, Se-Na;Kim, Jung-Bong;Cho, Young-Suk;Kim, Kwang-Yup;Kim, Haeng-Ryan;Kim, So-Young
    • Food Science and Preservation
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    • v.19 no.6
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    • pp.951-956
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    • 2012
  • In this study, the effects of the use of a starter on radish soaked at $4^{\circ}C$ for 28 days using two kinds of domestic sun-dried salt (white and gray salt) were determined. As a result, the moisture contents of the radish soaked with white and gray salt were 7.93 and 4.50%, respectively. The salinity levels were found to be equal (90%). No significant difference was found between the two groups in terms of the mineral contents of the salts therein ($37812.41{\pm}1922.95$ and $39755.13{\pm}1205.70$ mg/100 g, respectively). However, iron and zinc contents of gray salt were higher than those of white salt while the calcium, potassium, and magnesium contents were lower than those of white salt. After the addition of the starter, the sugar content increased, the pH decreased, and the total acidity rapidly decreased compared with the non-starter group during fermentation. The total microorganism count of the two groups increased during the fermentation period of 28 days. From the initial fermentation for 7 days, the lactic acid bacteria in the non-starter group increased while those in the leuconostoc starter group steadily increased within the whole fermentation period. The Leuconostoc spp. in non-starter group increased, but that in the starter group decreased to pH 4.0 on day 14.