• Title/Summary/Keyword: preparation condition

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A review of the taxonomic and ecological characteristics of Korean mistletoe types (Viscum, Korthalsella, Loranthus and Taxillus) (한국산 겨우살이류(Viscum, Korthalsella, Loranthus and Taxillus)의 분류 및 생태학적 특성 고찰)

  • Kim, Chan-Soo;Kim, Soo-Young;Sun, Byung-Yun;Yi, Jae Seon
    • Korean Journal of Plant Taxonomy
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    • v.43 no.2
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    • pp.81-89
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    • 2013
  • In general, studies of aerial parasitic plants known collectively as mistletoe have been carried out to investigate their ecological and agricultural characteristics. However, with the recently increased level of interest in medicinal resources, research on different types of Korean mistletoe has also increased. This study was carried out to review the work on the taxonomy and ecology of Korean mistletoe in preparation for the industrial use of these plants in the future. Mistletoe types are flowering plants belonging to Santalales, which exist in the form of parasites on the branches of trees or shrubs. In Korea, five taxa of four genera in two families of mistletoe exist: Viscum coloratum (Komarov) Nakai f. coloratum, Viscum coloratum (Komarov) Nakai f. rubroaurantiacum (Makino) Kitagawa and Korthalsella japonica (Thunb.) Engl. in Santalaceae, along with Loranthus tanakae Franch. et Sav. and Taxillus yadoriki (Sieb. ex Maxim.) Danser in Loranthaceae. As taxonomic studies of these species remain insufficient and given that the distribution ranges of these species are very wide, further observations pertaining to the morphological variations in each species are necessary. The distribution of mistletoes is known to be determined by the host specificity, the interval between the hosts, the environmental condition, the habits of the host plant, the eating characteristics of mediators in the area, and their habitat selection features.

The Synthesis of Potassium Hexatitanate Whisker by the Flux Process (융제법에 의한 육티탄산칼륨 Whisker의 합성)

  • Lee, Chul-Tae;Kim, Sung-Weon;Lee, Jin-Sik;Kim, Young-Myoung;Kwon, Kung-Taek
    • Applied Chemistry for Engineering
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    • v.5 no.3
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    • pp.478-500
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    • 1994
  • The preparation of potassium hexatitanate whisker by flux method was investigated. In this study, 8 types synthesis of flux such as $V_2O_5$, $Bi_2O_3$, $B_2O_3$, $Pb_3O_4$, KCl, $K_4P_2O_7$, $K_2WO_4$ and $K_2MoO_4$ were tested to find a suitable flux for the synthesis of potassium hexatitanate whisker. Effects of various reaction variables such as reaction temperature, time, $TiO_2$ mole ratio to $K_2CO_3$, flux mole ratio to the mixture of $K_2CO_3$ and $TiO_2$, and slow-cooling treatment on the crystallization of potassium hexatitanate whisker were investigated. $K_2MoO_4$ and $K_2WO_4$ were better flux than others tested for the synthesis of potassium hexatitanate. In the presence of $K_2MoO_4$ or $K_2WO_4$ flux, the optimum condition for the synthesis of potassium hexatitanate whisker was that reaction temperature of $1000{\sim}1100^{\circ}C$, reaction time of 5 hours, $TiO_2$ mole ratio to $K_2CO_3$ of 6.0, and flux mole ratio to mixture ($K_2O+nTiO_2$) of 4.0. Slow-cooling treatment showed good effect on the growth of long fibrous potassium hexatitanate.

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The Preparation of $TiO_2$ Coated Activated Carbon Pellets Driven by LED and Removal Characteristics of VOCs (LED구동 $TiO_2$ 코팅 활성탄소 펠렛 제조 및 VOCs 제거 특성)

  • Kim, Yesol;Kim, Do Young;Jung, Min-Jung;Kim, Min Il;Lee, Young-Seak
    • Applied Chemistry for Engineering
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    • v.24 no.3
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    • pp.314-319
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    • 2013
  • In this study, nitrogen doped $TiO_2$ ($N-TiO_2$) coated on an activated carbon pellet (ACP) was prepared using sol-gel and the solid state heat treatment of urea to improve the removal property of volatile organic compounds (VOCs). To explore the visible light photocatalytic activity of the ACP under the light emitting diods (LED), the removal property of benzene gas was characterized by gas chromatography. The SEM and BET results show that the increment of titanium tetra isopropoxide contents leads to the increased $TiO_2$ coating amount of ACP surface and decreased specific surface area. From the results of benzene gas removal, the breakthrough time of ACP10 increased about 2 times compared to that of the ACP. The improved performance was attributed to the $N-TiO_2$ coating on ACP surface, which could be more effective to remove benzene gas under the condition of LED lamp.

Effects of potassium channel modulators on the fatigue velocity of mouse skeletal muscle (K+ 통로 조절 약물이 마우스 골격근의 피로현상에 미치는 영향)

  • Lee, Ki-ho;Ryu, Pan-dong;Lee, Mun-han;Lee, Hang
    • Korean Journal of Veterinary Research
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    • v.35 no.2
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    • pp.245-254
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    • 1995
  • The density of ATP-sensitive potassium($K_{APT}$) channels, that open as intracellular ATP concentration falls below a critical level, is very high in skeletal muscle surface membrane and those high density may imply that $K_{ATP}$ channels have very important physiological roles. To elucidate a role of $K_{ATP}$ in relation to fatigue, the modulating effects of potassium channel openers and blockers on the fatigue velocity(FV) of mouse extensor hallucis longus muscle(EHL) were investigated in vitro. Twitch contraction was induced by an electrical field stimulation (EFS: 24-48V, 20ms, 0.2-4Hz) and resulting contraction force was isometrically recorded. The twitch forces were gradually decreased to 25% of initial contraction force(ICF) in $37.52{\pm}1.55sec$($mean{\pm}s.e.m.$, n=135), indicating the fatigue phenomena. The mean velocity for development of the fatigue was measured during the period that twitch force decreased to half($FV_{0/0.5}$) and during the period from half to 25%($FV_{0.5/0.25}$) of ICF. The fatigue was induced once every one hour and the tissue response was stable for up to 4 hours. In control condition, ICF was $5.8{\pm}0.12g$ (n=144) and decreased to 50% of ICF with the mean fatigue velocity of $0.182{\pm}0.006g/sec$($FV_{0/0.5}$, n=135) and from 50% to 25% of ICF with $0.084{\pm}0.004g/sec$($FV_{0.5/0.25}$, n=135). Cromakalim($50{\mu}M$) significantly increased $FV_{0.5/0.25}$(n=4). Glibenclamide($IC_{50}>50{\mu}M$), $Ba^{2+}$($IC_{50}=10{\mu}M$), 4-aminopyridine($FV_{0/0.5}$, $IC_{50}=0.5mM$; $FV_{0.5/0.25}$, $IC_{50}=2mM$) decreased both $FV_{0/0.5}$ and $FV_{0.5/0.25}$ concentration-dependently up to 75%. $TEA^+$(30mM), E-4031($10{\mu}M$), tolbutamide(1mM) decreased $FV_{0.5/0.25}$, but apamin(300nM) and $TEA^+$(10mM) showed no significant effects. Our results suggest that activation of the $K_{ATP}$ channels may be major cause of $K^+$ outflux during development of the fatigue and the isolated EHL muscle could be an useful experimental preparation in studying the fatigue phenomena in skeletal muscle. In addition, the possibility of activation of delayed rectifier during the fatigue development remains to be studied further.

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Preparation and biological evaluation of 99mTc tricarbonyl cysteine (테크네슘-99엠 트리카보닐 시스테인의 제조 및 생물학적 특성 평가)

  • Jang, Beom-su;Park, Kyung-bae;Yun, Hyo-in
    • Korean Journal of Veterinary Research
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    • v.44 no.1
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    • pp.15-21
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    • 2004
  • This paper describes the development of $^{99m}Tc$ tricarbonyl cysteine as potential renal function diagnostic radiopharmaceutical and evaluation of its biological characteristics using experimental animals. l-Cysteine was labeled efficiently with $^{99m}Tc$ tricarbonyl precursor $([^{99m}Tc(CO)_3(H_2O)_3)]^{+})$ under 30 min heating at ${75^{\circ}C}$. Labeling yield and stability were analyzed by high performance liquid chromatography (HPLC). The biodistribution property of $^{99m}Tc$ tricarbonyl cysteine in mice and its dynamic imaging profiles in rabbits were carried out. To investigate the excretion mechanism of $^{99m}Tc$ tricarbonyl cysteine, tubular transport inhibition test with probenecid was adopted. $^{99m}Tc$ tricarbonyl cysteine was obtained with a high labeling yield under the moderate condition. The results of biodistribution experiments of $^{99m}Tc$ tricarbonyl cysteine in ICR mice at 3 and 90 min provided that $^{99m}Tc$ tricarbonyl cysteine was very highly accumulated in the kidney and bladder, thereby almost 99% of $^{99m}Tc$ tricarbonyl cysteine was excreted within 90 min post injection. The same results were confirmed by the whole body dynamic images for 30 minutes and static images in rabbits at given time intervals after injection. Renogram of $^{99m}Tc$ tricarbonyl cysteine in rabbits showed that its $T_{max}$ and $T_{1/2}$ of $^{99m}Tc$ tricarbonyl cysteine were $2.33{\pm}0.56$ and $4.30{\pm}0.79$ min, respectively. The $T_{max}$ of $^{99m}Tc$ tricarbonyl cysteine with probenecid pretreatment was $2.30{\pm}0.17$ min, whereas $T_{1/2}$ of that with probenecid pretreatment was $17.0{\pm}32.47$ min. $T_{1/2}$ of $^{99m}Tc$ tricarbonyl cysteine with probenecid pretreatment was significantly different, as compared to the result without probenecid (p<0.0001). The results showed that the excretion of $^{99m}Tc$ tricarbonyl cysteine was extremely affected by probenecid. Therefore, $^{99m}Tc$ tricarbonyl cysteine was rapidly excreted from the kidney principally by the tubular secretion.

Influence of Early Childhood Care and Education on Children's Mental Health (I) - Status and Prospects of Child Care and Education Policies of Korea - (영유아보육이 아동의 정신건강에 미치는 영향 : 국내 영유아보육 정책의 실태와 전망)

  • Bahn, Geon Ho;Hong, Minha;Lee, Yeon Jung;Kwack, Young Sook;Joung, Yoo-Sook;Lee, Soyoung Irene;Kim, Bongseog;Sohn, Seok Han;Chung, Un-Sun;Yang, Jaewon;Bhang, Soo-Young;Hwang, Jun-Won;Oh, So Young;Han, Jaehyun;Lee, Jongwon
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.24 no.1
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    • pp.3-12
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    • 2013
  • Most preschool children in Korea attend kindergarten (KG) or a child care center (CCC). CCCs, which focus on caring for the child, belong to the ministry of health and welfare. On the other hand, KGs are responsible for education, and belong to the ministry of education, science and technology. In order to resolve the decline in population due to low birthrates, the government is expanding the free child care and education policies. CCCs and KGs are combined together to form the 'NURI curriculum' and supporting funds have been increased in both governmental departments. In addition, economic support is provided for homeschooling households. Because this is a nationwide policy and applies to every single household, thorough preparation regarding the effect and side effects must be made. This policy is currently being implemented, and as child and adolescent psychiatrists, great consideration should be given to the influence on the population. Therefore, the Korean Academy of Child and Adolescent Psychiatry intends to investigate the effects and problems of the nationwide policy by analyzing the current condition of Korea's free child care and education and foreign policies. In the current paper, we reviewed the developmental process of Korea's free child care and education policy, as well as suggested future directions.

Preparation TiO$_2$sol using aqueous system and characteristics of its thin film (수용계를 이용한 TiO$_2$Sol의 제조와 박막의 특성)

  • 김성도;조경식;김성진
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.10 no.3
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    • pp.271-277
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    • 2000
  • Transparent $TiO_2$ thin films were prepared by the sol-gel method from titanium alkoxide aqueous solution containing large quantities of water. To prepare the aqueous system sol, the chelate compound solution were prepared from each 1 mole of titanium(IV)iso-propoxide, acetylacetone and 8 moles of isopropyl-alcohol. And then the 50 moles aqueous solution with the 0.02~0.50 moles of HCI for sol stability and the 0.3 mole of polyethylene glycol for coating adhesion were precisely dropped on the chelate compound solution. $TiO_2$thin films were fabricated by dip coating, drying and heat treatment at $400^{\circ}C$ and their characteristics were investigated by XRD, SEM and UV-visible spectrometer, The neutral sol of composition with TTIP : AcAc : IPA : $H_2O$ : PEG : HCl = 1 : 1 : 8 : 50 : 0.3 : 0.15 (molar ratio) was maintained stable sol condition and without problem for coating more than 30 days. The anatase phase $TiO_2$thin film prepared from 30 times dipping, drying and heat treating showed the flat surface and the fine microstructure of fracture surface with about 2 $\mu\textrm{m}$ thickness. Transparency of these $TiO_2$thin film was 80 % in the visible region.

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Preparation and Characterization of Anti-reflective and Anti-static Double Layered Films by Sol-Gel Spin-Coating Method (졸-겔 스핀코팅법에 의한 반사방지 및 정전기방지 복층막의 제조 및 특성)

  • 이준종;최세영
    • Journal of the Korean Ceramic Society
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    • v.34 no.1
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    • pp.79-87
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    • 1997
  • Anti-reflective and anti-static double layered films were prepared on the VDT panel by sol-gel spin-coating method. Their electrical, opticla, and mechanical properties were investigated. The outer SiO2 film with low re-fractive index was coated over the inner ATO(Antimony-doped Tin Oxide)-SiO2 film which was prepared by mixing ATO sol with SiO2 at molar ratio of 68:32 to satisfy the interference condition of double layers. The heat treatment was conducted at 45$0^{\circ}C$ for 30 min where residual organics were completely removed. The sheet resistance of ATO single layer showed the minimum value of 6$\times$107$\Omega$/$\square$ at 3 mol% addition of Sb and that of SiO2/ATO-SiO2 increased slightly with increasing SiO2 mol% up to 30 mol%, and then increased steeply to the value of 3$\times$108$\Omega$/$\square$ at 32 mol%. The reflectance of double layered films was about 0.64% at the wavelength of 550nm and the transmittance increased about 3.20%. The hardness of double layered films was almost the same as that of uncoated VDT panel, 471.4kg.f/mm2.

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A study on Supply Extension Device of AED (AED의 보급 확대 방안에 관한 연구)

  • Koh, Jae-Moon;Kim, Young-Ho;Han, Sang-Hak
    • The Korean Journal of Emergency Medical Services
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    • v.9 no.2
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    • pp.147-168
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    • 2005
  • It examined the doubt point which AED motive relates until now, the AED should have bought a life how, present address of our country site pre-hospital care, comparison it tried to observe the advanced nation instance back. Gist of this research the AED important cold region once compared to informed to how many cardiac arrest patient, against him the what kind of preparation wanted informing the necessary cold region. It soaks simultaneously but the AED motive is widely supplied distant in future and it is generality and it is feeble but it wanted doing one morning. The habit difference of an American who does of course meat diet mainly and a Korean is many and it compares in the United States and the cardiac arrest patient comparison occurs holds a point few. To become Western anger but and be caused by with thin dietary life, stanching bleeding cung, with the fact that the heart attack is increasing rapidly with the hyperextension. It is a talk which anyone it knows all. The major league most Choi huy Sub in condition will catch the ball which floats and the multi co-player and to collide when falling down, the medical device which is committed with emergency aid is AED motive. From the United States subway station and the shopping which are a public place on the baseball field outside the jar which it will drive, the museum and the school, easily there is it will be able to discover the AED from the court of justice back. The Pittsburg university the students per the individual $30 the core phyey were receiving the smallness lifestyle alcoholic beverage and a AED motive actual training with mercy of degree. From the United States distant in future the AED motive is sold even from the retail store and. From our country like this plan government offices temporary disposal education from from 119 fire fighters emergency structure company in fire fighting government employee and nursing must magnify a former enterprise rainy spell in summer multi temporary disposal education with the head which it will burn with the head. This plan in early rising will be able to become fixed in Korea it forecasts with the fact that. The research which it sees it leads and like the United States to some day become fixed even from our country to believe and suspicion it is not and in the people in approach ease one AED supply plan fire fighting government employees stand in the first and feed with the fact that must be positive at this enterprise they become.

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A Study on Urinary Incontinence of Elderly Women in a Community (노인여성의 요실금 실태)

  • Park, Ok-Hee;Kwon, In-Soo;Kang, Young-Sil
    • Women's Health Nursing
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    • v.7 no.4
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    • pp.536-546
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    • 2001
  • The purposes of this descriptive study were to identify the prevalence rate of urinary incontinence(UI) and the differences in frequency of incontinent and normal women by general characteristics, obstetrical history, and the conditional events for urinary incontinence of the elderly women in a community. By the results of this study, it is intended to provide nursing practice guidelines for incontinent women. The research design of this study was a preliminary descriptive study. The 173 subjects were 55 years old and over, and resided in a small city area. Data were collected from June 20 to July 20, 2001, by an interview or a self-report with questionaire. The questionaire was composed of items of general characteristics, obstetrical characteristics, and conditions of UI by the modified Henderickon's Stress Incontinence Scale(1981). The results were summariezed as follows: 1. The UI prevalence rate of the sample was 64.2%. Of the incontinent women, 31.5% had experienced UI for a period of three to five years, and 84.7% had never treated or managed their UI. Frequency of UI was once or twice times per month(46.8%). 2. The total mean of UI on the scale in the incontinent women was 25.50 of 85, ranging from 18 to 41. 3. The most frequent condition of UI was coughing, followed by laughing, sneezing, heavy exercise, and preparation of urination in descending order. 4. There were significant differences in age, education, social activity, and urinary difficulty between the incontinent women and the normal women. 5. There were significant differences in frequency of spontaneous abortion, age of menopause between the incontinent women and the normal women. 6. There were no significant differences in number of delivery, frequency of artificial abortion, age of the last delivery, and postal health management between the incontinent women and the normal women. In conclusion, the incidence of UI in this study was high, but there were no effective treatments or management. It is suggested to provide the adult women with knowledge about UI, and to educate preventive behavior and control skill of urinary incontinence. Also episodes of urinary incontinence were high in the situation of sudden increase of abdominal pressure. This data can be used for the prevention strategy of urinary incontinence, In future research it is recommended to identify comprehensive factors related to urinary incontinence including psychosocial factors, and effective strategies of urinary incontinence.

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