• Title/Summary/Keyword: $C_V$

Search Result 13,374, Processing Time 0.057 seconds

Antidiabetic Effect of Korean Red Ginseng by Puffing Process in Streptozotocin-Induced Diabetic Rats (Streptozotocin 유발 당뇨쥐에서 팽화가공 처리한 홍삼의 항당뇨 효과)

  • Kim, Shin-Hee;Kang, Ju-Seop;Lee, Sang-Jun;Chung, Young-Jin
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.37 no.6
    • /
    • pp.701-707
    • /
    • 2008
  • Antidiabetic effect of Korean red ginseng (RG) processed by puffing in streptozotocin (STZ)-induced diabetic (DM) rats was investigated. Five week-old SD rats were divided into four groups; normal control (NC) group, DM group, red ginseng (RG) group and puffed red ginseng (PG) group. The RG and PG groups were orally provided with RG or PG dissolved in water (500 mg/kg) respectively for seven weeks after single injection of STZ (50 mg/kg, i.v.) followed by identification of DM. NC group received saline vehicle instead of STZ. At the end of feeding of RG or PG, the changes of fasting blood glucose, serum insulin and amylase level and serum lipid profiles were evaluated. Also, oral glucose tolerance test (OGTT), comet assay and histopathological examination were performed. At 7th week, the fasting blood glucose levels of the RG and PG groups were reduced compared to the DM group by 11.54% and 20.22%, respectively. The result of OGTT did not show significant differences among DM and two red ginseng groups. While serum insulin and TG levels were predominantly improved in PG group (p<0.05), serum amylase level was increased in RG group. Alkaline comet assay for checking the oxidative damage of DNA showed that TL (tail length, ${\mu}m$) and TM (tail moment) in the blood lymphocyte of PG group significantly decreased in contrast with DM group. Histopathological results of pancreas showed that destruction of exocrine as well as endocrine might be cured by the administration of RG and PG. These results suggest that PG could exert more protection against STZ-induced toxicity than RG group.

Flora of aquatic and wetland habitats on Jeju Island (제주도의 수생 및 습생 식물상)

  • Kang, Dae-Hyun;Yim, Eun-Young;Moon, Myung-Ok
    • Korean Journal of Plant Taxonomy
    • /
    • v.45 no.1
    • /
    • pp.96-107
    • /
    • 2015
  • This study presents a comprehensive account of the flora of hydrophytes and hygrophytes on Jeju Island. This approach aims to contribute to fundamental information about the conservation of plant diversity in wetlands. Field surveys were carried out from May of 2010 to September of 2014 in various types of wetlands on Jeju Island. A total of 189 taxa, including 52 families, 98 genera, 181 species, 6 varieties, 2 forma and 189 taxa, were found. Among them, 99 taxa (38 families, 60 genera, 96 species and 3 varieties) were hydrophytes and 90 taxa (23 families, 45 genera, 85 species, 3 varieties and 2 forma) were hygrophytes. In addition, Eleocharis${\times}$yezoensis H. Hara (Cyperaceae) was newly added to the flora of Korea. The protected wild plants designated by the Ministry of the Environment were 5 taxa, including Brasenia schreberi J. F. Gmel. and Dysophylla yatabeana Makino. The endangered species found included one Critically Endangered Species (i.e., Mankyua chejuense B.-Y. Sun, M. H. Kim & C. H. Kim), 5 Endangered Species (e.g., Lysimachia leucantha Miq.) and 7 Vulnerable Species (e.g., Tillaea aquatica L.). The floristic regional indicator plants found in this area were 44 taxa comprising 10 taxa of grade V, 7 taxa grade IV, 15 taxa of grade III, 5 taxa of grade II, and 7 taxa of grade I. The identified naturalized plants were 10 taxa; 8 families, 8 genera, 9 species and 1 variety. In the wetlands on Jeju Island, high plant species diversity was shown, and a number of rare plants and phytogeographically important plants were found. For these reasons, we consider that the wetlands on Jeju Island are very important areas from a botanical point of view. It is necessary to establish specific protection and maintenance policies in an effort to conserve these wetlands and species.

A Literature Review of The Senile Hypotension (노인(老人) 저혈압(低血壓)에 대(對)한 문헌적(文獻的) 고찰(考察))

  • Kwak, Ik-Hoon;Kim, Jong-Dae;Jeong, Ji-Cheon
    • The Journal of Dong Guk Oriental Medicine
    • /
    • v.4
    • /
    • pp.161-187
    • /
    • 1995
  • This study was perfomed to investigate causes of the senile hypotension, pathogenic mechanism, symptoms, and therapies through medical literatures, recent chinese medical literatures and chinese medical journals. The results are as follows ; 1. The senile hypotension has major symptoms of dizziness, weakness, syncope, palpitation, shortness of breath, and deficiency of Qi. Additionally, it has minor symtoms of letharhy, isomnia, tinnitus, amnesia etc... 2. The prodromal symptoms of Kwul and Kwul are relating to the symptoms of tachycardia, facial pallor, sweating, anxietas, ambiguous consciousness, and fainting. Weakness and dizziness due to deficiency make the symptoms of exhaustion, fatigue, vertigo, lethargy, and brachycardia. 3. The most principal cause of the senile hypotension is deficiency of Shen due to aging, congenital deficiency, and chronic illness. The rest of causes are defciency of Qi and blood, phlegm of retention, stagnation of Qi, blood stasis, blood prostration etc... In the view of the occidental meicine, the causes of the senile hypotension came from the reduction of cardiac output, the decretion of cardiovascular system's extention due to aging, hereditary factor, secondary factor due to exsanguination, diabetes mellitus, C.V.A etc..., and factor of neurogenic system's degeneration. 4. The principal pathogenic mechanisms are the insufficiency of Xing-Yang, the deficiency of Qi in middle jiao, and deficiency of Shen-Qi. The rest of mechanisms are the deficiency of both Qi and blood, stagnation of the Gan-Qi, and the deficiency of Gan and Shen. Zang-Pu Organs have something to do with Xing, Bi, and Shen. 5. As principal therapies, there are warming and recuperation the Xing-Yang, strengthing the middle-jiao and replenishing Qi, replenishing vital essence to tonify the Shen, and warming and recuperation the Shen-Yang. Additionally, the therapies of invigorating the Bi and relieving mental stress, strengthning the Bi and tonifing the Shen, invigorating Qi and nourishing Yin, soothing the Gan and regulating the circulation of Qi, and tonifing the Shen and nourishing the Gan help the cure of the senile hypotension. In prescriptions there are Baohe Yuan Tang, Buzhong Yigi Tang, Zuoguei Yin, Yougui Yin, Guipi Tang, Zhu Fu Tang, Shengmai San, Sini San, and Qi Ju Dihuang Wan. The medical herbs of Astragali Radix, Codonopsitis Pilosulae Radix, Ginseng Radix, Aconiti Tuber, Ephedrae Herba, Cinnamomi Ramulus, Cinnamomi Corfex Spissus, Zingiberis Rhizoma, Polygalae Radix, Liriopis Tuber, Polygonati Sibirici Rhifoma, Lycii Fructus, Schizandrae Fructus, and Glycyrrhizae Radix can be treated. 6. According to the clinical report, the principal causes are the deficiency of Qi, and insufficiency of Yang which symptoms are dizziness, vitality fatigue and acratia, amnesia, body cold and alger of extremity, spontaneous perspiration, and therady and weak pulse. It was improved by taking WenYang YiQi Tang, Zhu Fu Tang about 20-30 days. The improvement was shown on disappearance of subjective symptoms or the ascending of blood pressure to normal figure, and the rate of improvement was over 70%. 7. As regimens, taking warming and recuperating food(a sheep mutton, juglans regia, chiness date, longan aril etc...) and pungent food(chinese green onion, fress ginger, pipers fructns etc...), doing physical training, not being ill in bed at a long time, and preventing descent of blood pressure coming from sudden change of posture are needed. Additionally, the usage of diuretic, abirritant, and depressor needs to be extra cautious.

  • PDF

Effect of Pine (Pinus densiflora) Needle Hot Water Extract on Antioxidant Activity in Rats Treated with Carbon Tetrachloride (적송잎 열수 추출물이 사염화탄소를 투여한 흰쥐의 항산화 활성에 미치는 영향)

  • Park, Yong-Soo;Park, Mi-Ra;Jeon, Min-Hee;Hwang, Hyun-Jung;Kang, Min-Suk;Kim, Bo-Kyung;Kim, Sung-Gu;Lee, Sang-Hyeon;Kim, Mi-Hyang
    • Journal of Life Science
    • /
    • v.21 no.4
    • /
    • pp.604-609
    • /
    • 2011
  • Pine (pinus densiflora) needles have long been used as a traditional health-promoting medicinal food in Korea. This study was conducted to investigate the effects of pine needle extracts on the hepatic antioxidant system in the damaged liver of carbon tetrachloride ($CCl_4$)-treated rats. Nine-week-old Sprague Dawley rats were divided into four groups: normal group (NOR), $CCl_4$-treated group (CCL), pine needle hot water extract and $CCl_4$-treated group (CCL-P), and Vitamin C and $CCl_4$-treated group (CCL-V). The enzyme activities and antioxidant effects of the pine needle hot water extracts were investigated at the levels of liver homogenates and serum of rats intoxicated with $CCl_4$. Serum GOT and GPT activities by $CCl_4$ treatment increased compared to those of the NOR group. However, they tended to decrease in the hot water extract-administered group. Liver SOD activity in the CCL group was significantly lower than the NOR group (p<0.05). However, they increased in the CCL-P group compared to the CCL group. Further, the CAT and GPx activities of serum treated with $CCl_4$ were higher compared to those of the NOR group but lower in the CCL-P group compared to CCL group. These results suggest that pine needle hot water extract increases antioxidant activities.

Plankton Community Response to Physico-Chemical Forcing in the Ulleung Basin, East Sea during Summer 2008 (2008년 하계 울릉분지에서 관측된 물리·화학적 외압에 대한 플랑크톤 군집의 반응)

  • Rho, Tae-Keun;Kim, Yun-Bae;Park, Jeong-In;Lee, Yong-Woo;Im, Dong-Hoon;Kang, Dong-Jin;Lee, Tong-Sup;Yoon, Seung-Tae;Kim, Tae-Hoon;Kwak, Jung-Hyun;Park, Hyun-Je;Jeong, Man-Ki;Chang, Kyung-Il;Kang, Chang-Keun;Suh, Hae-Lip;Park, Myung-Won
    • Ocean and Polar Research
    • /
    • v.32 no.3
    • /
    • pp.269-289
    • /
    • 2010
  • In Summer 2008, a multidisciplinary survey was conducted onboard R/V Haeyang 2000 to understand plankton response to the three distinct physico-chemical settings that developed in the Ulleung Basin of the East Sea. Baseline settings of hydrographic conditions included the presence of the thin (<20 m) Tsushima Surface Water (TSW) on top of the Tsushima Middle Water (TMW). It extends from the Korea Strait to $37^{\circ}N$ along the $130^{\circ}E$ and then turns offshore and encompasses the relatively saline (T>$26^{\circ}C$, S>33.7) Ulleung Warm Eddy surface water centered at $36.5^{\circ}N$ and $131^{\circ}E$. A relatively colder and saline water mass appeared off the southeastern coast of Korea. It was accompanied by higher nutrient and chlorophyll-a concentrations, suggesting a coastal upwelling. Most of the offshore surface waters support low phytoplankton biomass (0.3 mg chl-a $m^{-3}$). A much denser phytoplankton biomass (1-2.3 mg $m^{-3}$) accumulated at the subsurface layer between 20-50 m depth. The subsurface chlorophyll-a maximum (SCM) layer was closely related to the nutricline, suggesting an active growth of phytoplankton at depth. The SCM developed at shallow depth (20-30 m) near the coast and deepened offshore (50-60 m). A fucoxanthin/zeaxanthin ratio was high in coastal waters while it was low in offshore waters, which indicated that diatoms dominate coastal waters while cyanobacteria dominate offshore waters. The community structure and biomass of phytoplanktonare closely related to nitrogen availability. Zooplankton biomass was higher in the coastal region than in the offshore region while species richness showed an opposite trend. Zooplankton community structure retained a coastal/offshore contrast. These suggest that summer hydrography is a stable structure, lasting long enough to allow a hydrography-specific plankton community to evolve.

A Review of Responses of Nursing Students Following Clinical Maternity Nursing Practice (모성 간호 실습 후 분만과정에 대한 간호학생의 심리적 반응 고찰 -모성 간호 실습, 실습에 대한 간호학생의 심리적 반응-)

  • Cho, Cheong-Ho
    • 모자간호학회지
    • /
    • v.4 no.1
    • /
    • pp.41-51
    • /
    • 1994
  • The purposes of this study were to identify responses of nursing students following clinical maternity nursing practice, to develop data of further effective clinical maternity nursing practice, to understand nursing students perceive the natural maturation process toward pregnancy delivery and puerperal process, to help the nursing students achieve personality growth and development through clinical maternity nursing practice. The subjects were 35 senior nursing students from the Department of Nursing Science of Chung-Ang University. The data were collected from the 1st semester (Feb.22$\sim$June 9) to the 2nd semester(Aug.23$\sim$Nov.10), 1993 through self-reporting using an open ended questionnaire about perception and feelings regarding the normal delivery process. The data analysis used descriptive method. Results of the study were as follows : 1. Following clinical practice in maternity nursing, the responses of the nursing students were collected included both positive and negative aspects. The positive responses were classified in to four categories and each category included subgroups. One group, labelled as $\ulcorner$The birth of noble life$\lrcorner$ had a subgroup, (I felt the mystery and wonder of life), another group, $\ulcorner$After delivery, comfort and satisfaction$\lrcorner$ with the subgroup (I can bear to see the comfort and relief beyond pain) (C/S is better than vaginal delivery) (Very easy), the 3rd group, $\ulcorner$ I realized family friendship and support$\lrcorner$ with subgroup (Honorable, Magnificient) (I thank my parents ) (It's good to looking at my husband's support), and the 4th group, $\ulcorner$The birth of a healthy baby$\lrcorner$, with its subgroup, (baby looks pretty and healthy). 2. The negative responses were classified in eight categories and each category included subgroups. One group labelled as $\ulcorner$Fear$\lrcorner$, had subgroups of (Terrible, Horrible) (Shock) (Dread), another group, $\ulcorner$Tension$\lrcorner$, and its subgroup, (I became tense about stories heard before clinical practice), the 3rd group, $\ulcorner$surprise$\lrcorner$ and its subgroup (I was surprised at the delivery process), the 4th group, $\ulcorner$Power lessness$\lrcorner$ and its subgroup, (I watched the labor pain impatiently), the 5th group $\ulcorner$Apathy$\lrcorner$ ; and its subgroup, (I didn't feel the empathy for the labor pain of the pregnant women), the 6th group, $\ulcorner$Disgust$\lrcorner$ and its subgroup, (Disgust, Embarrassed), the 7th group, $\ulcorner$Inevitable destiny$\lrcorner$ and its subgroups (necessity of self-sacrifice and difficulty) (I accepted it as a women's destiny) (I can't do it), the last group, $\ulcorner$There seems to be trouble$\lrcorner$ and its subgroup, (It seems to have been a little too hard for mother and baby). Suggestions for further studies are as follows : 1. Nursing students should receive intensive education about $\ulcorner$The birth of noble life$\lrcorner$ $\ulcorner$After delivery, comfort and satisfaction$\lrcorner$ $\ulcorner$I realized family friendship and support$\lrcorner$ $\ulcorner$The birth of a healthy baby$\lrcorner$, so that a more positive attitude can be developed before clinical maternity nursing. 2. Nursing students should be given an orientation which is reality based and related clinical maternity nursing (using for A.V. Materials), so that they will not feel they tension, of the negative categories. 3. Nursing students should be received articles on Pain Relief Method, so that they will be prepared activie and positive in the clinical practice, and therefore they will not feel the powerlessness, of the negative categories. 4. F/U for responses of nursing students should be checked following clinical maternity nursing to evaluate the effects of the instruction.

  • PDF

The Effects of Inductive Activities Using GeoGebra on the Proof Abilities and Attitudes of Mathematically Gifted Elementary Students (GeoGebra를 활용한 귀납활동이 초등수학영재의 증명능력 및 증명학습태도에 미치는 영향)

  • Kwon, Yoon Shin;Ryu, Sung Rim
    • Education of Primary School Mathematics
    • /
    • v.16 no.2
    • /
    • pp.123-145
    • /
    • 2013
  • This study was expected to yield the meaningful conclusions from the experimental group who took lessons based on inductive activities using GeoGebra at the beginning of proof learning and the comparison one who took traditional expository lessons based on deductive activities. The purpose of this study is to give some helpful suggestions for teaching proof to mathematically gifted elementary students. To attain the purpose, two research questions are established as follows. 1. Is there a significant difference in proof abilities between the experimental group who took inductive lessons using GeoGebra and comparison one who took traditional expository lessons? 2. Is there a significant difference in proof attitudes between the experimental group who took inductive lessons using GeoGebra and comparison one who took traditional expository lessons? To solve the above two research questions, they were divided into two groups, an experimental group of 10 students and a comparison group of 10 students, considering the results of gift and aptitude test, and the computer literacy among 20 elementary students that took lessons at some education institute for the gifted students located in K province after being selected in the mathematics. Special lesson based on the researcher's own lesson plan was treated to the experimental group while explanation-centered class based on the usual 8th grader's textbook was put into the comparison one. Four kinds of tests were used such as previous proof ability test, previous proof attitude test, subsequent proof ability test, and subsequent proof attitude test. One questionnaire survey was used only for experimental group. In the case of attitude toward proof test, the score of questions was calculated by 5-point Likert scale, and in the case of proof ability test was calculated by proper rating standard. The analysis of materials were performed with t-test using the SPSS V.18 statistical program. The following results have been drawn. First, experimental group who took proof lessons of inductive activities using GeoGebra as precedent activity before proving had better achievement in proof ability than the comparison group who took traditional proof lessons. Second, experimental group who took proof lessons of inductive activities using GeoGebra as precedent activity before proving had better achievement in the belief and attitude toward proof than the comparison group who took traditional proof lessons. Third, the survey about 'the effect of inductive activities using GeoGebra on the proof' shows that 100% of the students said that the activities were helpful for proof learning and that 60% of the reasons were 'because GeoGebra can help verify processes visually'. That means it gives positive effects on proof learning that students research constant character and make proposition by themselves justifying assumption and conclusion by changing figures through the function of estimation and drag in investigative software GeoGebra. In conclusion, this study may provide helpful suggestions in improving geometry education, through leading students to learn positive and active proof, connecting the learning processes such as induction based on activity using GeoGebra, simple deduction from induction(i.e. creating a proposition to distinguish between assumptions and conclusions), and formal deduction(i.e. proving).

Characterization of Physiological Properties in Vibrio fluvialis by the Deletion of Oligopeptide Permease (oppA) Gene (Vibrio fluvialis oligopeptide permease (oppA) 유전자 deletion에 의한 생리적 특성)

  • Ahn Sun Hee;Lee Eun Mi;Kim Dong Gyun;Hong Gyoung Eun;Park Eun Mi;Kong In Soo
    • Journal of Life Science
    • /
    • v.16 no.1
    • /
    • pp.131-135
    • /
    • 2006
  • Oligopeptide is known to be an essential nitrogen nutrient for bacterial growth. Oligopeptide can be transported into cytoplasm by a specific transport system, Opp system. Opp system is composed of five proteins, which are transcribed by an operon. These are responsible for oligopeptide binding protein (OppA), permease (OppB and OppC) and energy generation system (OppD and OppF), respectively. Previously, we isolated the opp operon from Vibrio fluvialis and constructed the oppA mutant by allelic exchange method. In this study, we investigated the growth pattern and biofilm production under the different growth condition. When the cells were cultivated using brain heart infusion(BHI) medium, the wild type was faster than the mutant in growth during the exponential phase. However, it showed that the growth pattern of two strains in M9 medium is very similar. The growth of wild type showed better than that of the mutant grown at pH 8. At pH 7, there was no an obvious difference in growth. After 5 mM $H_2O_2$ was treated to the cells $(OD_{600}=1.2)$, the cell survival was examined. The oppA mutation did not affect in survivability. In the presence of $10{\mu}g/ml$ polymyxin B, the biofilm production of the oppA mutant was higher than that of the wild type.

Electro chemical characteristics of $(MnX)O_2$ electrode prepared by thermal decomposition method (열분해법으로 제조된 $(MnX)O_2$ 전극의 전기화학적 특성)

  • Kim, Hyun-Sik;Lee, Hae-Yon;Huh, Jeoung-Sub;Kim, Jong-Ryung;Lee, Dong-Yoon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2003.11a
    • /
    • pp.348-351
    • /
    • 2003
  • 산소 과전압이 낮은 $MnO_2$를 촉매로 사용하여 반도체 산화물계의 산소선택성 전극을 제조하고 산화물 coating층의 미세구조와 전기화학적 특성을 분석하였다. Ti 기판에 열분해 법을 이용하여 $MnO_2$ 피막을 형성하였고, 또한 PVDF : $MnO_2$의 함량비를 1 : 1에서 1 : 40까지 정량적으로 변화시키고 DMF의 함량을 각각의 고정된 PVDF : $MnO_2$의 함량비에서 변화시켜 Pb전극에 1.5 mm/sec의 속도로 5회 dipping하여 $MnO_2$ 피막층을 형성 하였다. $450^{\circ}C$에서 1시간 열분해하여 약 $1\;{\mu}m$$MnO_2$ 피막층이 형성되었으나 Ti 기판과의 접착력이 약하여 피막자체에 대한 전기화학적 특성을 관찰할 수 없었다. PVDF : DMF = 4 : 96인 경우 pb 전극의 피막층이 얇기 때문에 박리현상이 일어났으며 이는 산화물 용제의 낮은 점도 때문인 것으로 판단된다. 또한 PVDF : DMF = 10 : 90의 경우는 5회 dipping 하여 약 $150\;{\mu}m$의 피막층을 형성하였다. PVDF : $MnO_2$의 함량비가 1:1에서 1:6 까지는 DMF의 함량에 무관하게 전극 특성이 나타나지 않았지만 $MnO_2$의 양이 상대적으로 증가하면 cycle이 증가하더라도 거의 일정한 전류 값을 갖고 $MnO_2$와 PVDF의 비가 20:1 이상의 조성에서는 균일한 CV 특성을 나타냈다. 이는 $MnO_2$가 효과적으로 촉매 작용을 한 것으로 판단되며 anodic polarization에 의한 산소 발생 과전압도 약 1.4V 정도로 감소되었다.동등한 MSIL 코드를 생성하도록 시스템을 컴파일러 기법을 이용하여 모듈별로 구성하였다.적용하였다.n rate compared with conventional face recognition algorithms. 아니라 실내에서도 발생하고 있었다. 정량한 8개 화합물 각각과 총 휘발성 유기화합물의 스피어만 상관계수는 벤젠을 제외하고는 모두 유의하였다. 이중 톨루엔과 크실렌은 총 휘발성 유기화합물과 좋은 상관성 (톨루엔 0.76, 크실렌, 0.87)을 나타내었다. 이 연구는 톨루엔과 크실렌이 총 휘발성 유기화합물의 좋은 지표를 사용될 있고, 톨루엔, 에틸벤젠, 크실렌 등 많은 휘발성 유기화합물의 발생원은 실외뿐 아니라 실내에도 있음을 나타내고 있다.>10)의 $[^{18}F]F_2$를 얻었다. 결론: $^{18}O(p,n)^{18}F$ 핵반응을 이용하여 친전자성 방사성동위원소 $[^{18}F]F_2$를 생산하였다. 표적 챔버는 알루미늄으로 제작하였으며 본 연구에서 연구된 $[^{18}F]F_2$가스는 친핵성 치환반응으로 방사성동위원소를 도입하기 어려운 다양한 방사성의 약품개발에 유용하게 이용될 수 있을 것이다.었으나 움직임 보정 후 영상을 이용하여 비교한 경우, 결합능 변화가 선조체 영역에서 국한되어 나타나며 그 유의성이 움직임 보정 전에 비하여 낮음을 알 수 있었다. 결론: 뇌활성화 과제 수행시에 동반되는 피험자의 머리 움직임에 의하여 도파민 유리가 과대평가되었으며 이는 이 연구에서 제안한 영상정합을 이용한 움직임 보정기법에 의해서 개선되었다. 답이 없는 문제, 문제 만들기, 일반화가 가능한 문제 등으로 보고, 수학적 창의성 중 특히 확산적 사고에 초점을 맞추어 개방형 문제가 확산적 사고의 요소인 유창성, 독창성, 유연성 등에 각각 어떤 영향을 미치는지 20주의 프로그램을 개발, 진행하여 그 효과를 검증하고자

  • PDF

Analysis of Signal Properties in accordance with electrode area of x-ray conversion material (X선 검출 물질의 전극 면적에 따른 신호특성 분석)

  • Jeon, S.P.;Kim, S.H.;CHO, K.S.;Jung, S.H.;Park, J.K.;Kang, S.S.;Han, Y.H.;Kim, K.S.;Mun, C.W.;Nam, S.H.
    • Journal of the Korean Society of Radiology
    • /
    • v.4 no.1
    • /
    • pp.5-9
    • /
    • 2010
  • In recent, a digital x-ray detector attracted worldwide attention and there are many studies to commercialize. There are two methods in digital x-ray detector. This method is an Indirect method and Direct method. This study is to see the differences between the digital x-ray detector based on a-Se used in the existing indirect conversion method and an x-ray conversion material that has better SNR(Signal-to-noise ratio) and property than the a-Se. To solve the problem that is difficult to make a large area film using Screen-Print method, we used a Screen-Print method. In this study, we used a polyclystal $HgI_2$ as x-ray conversion material and a sample thickness is $150{\mu}m$ and an area is $3cm{\times}3cm$. ITO(Indium-Tin-Oxide) electrode was used as top electrode using a Magnetron Sputtering System and each area is $3cm{\times}3cm$, $2cm{\times}2cm$ and $1cm{\times}1cm$ and then we evaluated darkcurrent, sensitivity and SNR of the $HgI_2$ film are measured, then we evaluated the electrical properties. And we used a current integration mode when I-V test. This experiment shows that the sensitivity increases in accordance with the area of the electrode but the SNR is decreased because of the high darkcurrent. Through fabricating of various thicknesses and optimal electrodes, we will optimize SNR in the future work.