Poly(vinylbenzyl chloride-glycidyl methacrylate)/Polyethylene Composite Anion Exchange Membranes for Vanadium Redox Battery Application

Min-A Park,심준목,Se-Kook Park,전재덕,진창수,이기봉,신경희 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.6

Anion exchange membranes for a vanadium redox flow battery (VRB) were prepared by pore-filling on a PE substrate with the copolymerization of vinylbenzyl chloride (VBC) and glycidyl methacrylate (GMA). The ion exchange capacity, water uptake and weight gain ratio were increased with a similar tendency up to 65% of GMA content, indicating that the monomer improved the pore-filling degree and membrane properties. The vanadium ion permeability and open-circuit voltage were also investigated. The permeability of the VG65 membrane was only 1.23 × 10−7 cm2 min−1 compared to 17.9 × 10−7 cm2 min−1 for Nafion 117 and 1.8 × 10−7 cm2 min−1 for AMV. Consequently, a VRB single cell using the prepared membrane showed higher energy efficiency (over 80%) of up to 100 cycles compared to the commercial membranes, Nafion 117 (ca. 58%) and AMV (ca. 70%).

Poly(vinylbenzyl chloride-glycidyl methacrylate)/Polyethylene Composite Anion Exchange Membranes for Vanadium Redox Battery Application

Park, Min-A,Shim, Joonmok,Park, Se-Kook,Jeon, Jae-Deok,Jin, Chang-Soo,Lee, Ki Bong,Shin, Kyoung-Hee Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.6

Anion exchange membranes for a vanadium redox flow battery (VRB) were prepared by pore-filling on a PE substrate with the copolymerization of vinylbenzyl chloride (VBC) and glycidyl methacrylate (GMA). The ion exchange capacity, water uptake and weight gain ratio were increased with a similar tendency up to 65% of GMA content, indicating that the monomer improved the pore-filling degree and membrane properties. The vanadium ion permeability and open-circuit voltage were also investigated. The permeability of the VG65 membrane was only $1.23{\times}10^{-7}\;cm^2\;min^{-1}$ compared to $17.9{\times}10^{-7}\;cm^2\;min^{-1}$ for Nafion 117 and $1.8{\times}10^{-7}\;cm^2\;min^{-1}$ for AMV. Consequently, a VRB single cell using the prepared membrane showed higher energy efficiency (over 80%) of up to 100 cycles compared to the commercial membranes, Nafion 117 (ca. 58%) and AMV (ca. 70%).

12주간의 태권도 트레이닝이 남자 청소년의 골밀도 및 골 건강관련 호르몬에 미치는 영향

김민형 ( Min Hyung Kim ),정현철 ( Hyun Chul Jung ),강효정 ( Hyo Jung Kang ),김현배 ( Hyun Bae Kim ),송종국 ( Jong Kook Song ) 한국스포츠정책과학원(구 한국스포츠개발원) 2012 체육과학연구 Vol.23 No.4

The purpose of the study was to evaluate the effects of weeks taekwondo training on bone mineral density, and calcemic hormones in male adolescents. 19 male adolescents aged 13-14 years (12 for training group; 7 for control group) were participated in this study. Taekwondo group has been performed 50 minutes a days a week for 12 weeks, as exercise intensity of 60-70 % HRR (heart rate reserver). Control group have only performed the activities included in their physical education classes. Skeletal maturity was assessed by TW3. Bone mineral density at the sites of lumber spine, forearm, femur and whole body were assessed by DXA (Hologic. QDR-4500, USA). Blood samples were drown in the morning after 12-h fast and spun at 3000 rpm for 15 min. 25(OH)D and calcitonin were analyzed by Liaison (Diasorin, USA). Osteocalcin was analyzed by COBAR 5010 (Quantum Packard. USA). Parathyroid hormone was analyzed by E170 (Roche, Germany) and growth hormone was analyzed by Immulite 2000 (DPC, USA). Statical analyses were done with SAS version 9.2. All data were presented in terms of means and standard deviations. Two-wany ANOVA with repeated measure was used for interaction of time x group. Paired t-test was perfomed to change over time in each parameter. Multiple regression analysis was used to find factors that influence dependent variables. A statistically significant level was defined as 95%. The results of this study indicates that bone age for TG (14.9±0.62yr) was significantly advanced compared to chronological age (14.0±0.64yr). but CG had similar bone age (14.1±0.55yr) compared to chronological age (13.9±0.46yr). significant within subjects effects were found for whole body BMD(p<.001), lumbar BMD (p<.001) and forearm BMD (p<.0001). Significant increase could be obtained in TG for whole body BMD, lumbar BMD, and forearm BMD between pre and post-tests However, there was no difference for femoral BMD for both TG and CG. Although no difference was found for serum osteocalcin in CG, significant increase could be observed in TG between pre and post-tests. There was significant within subject effect for PTH in TG (p<.05). Significant interaction effect of group and time was found for GH (p<.0001). serum 25 (OH)D was significantly decreased in both groups throughout the study periods. Bone age, serum calcitonin and lean tissue were predictors for whole body BDM in explaining 51.0%, 64% and 74.0% respective in TG. Bone age was significant predictor for lumbar BMD in explaining 39.0% in TG. In conclusion, 12 weeks taekwondo training has positive effects on bone mineral density and calcemic hormones in male adolescents. Further study is needed to enhance femral BMD as taekwondo training over 12 weeks and higher intensity. 이 연구의 목적은 12주간의 태권도 트레이닝이 남자 청소년의 골밀도와 골 건강관련 호르몬에 미치는 영향을 규명하는 것이었다. 연구대상자는 13~14세 남자 청소년 19명이었으며, 이들을 훈련군(12명)과 통제군(7명)으로 분류하였다. 골격성숙도는 TW3 방법을 적용하여 RUS 점수와 뼈나이를 평가하였고, 골밀도는 DXA를 이용하여 측정하였다. 골 건강관련 호르몬은 osteocalcin(OC), calcitonin(CC), parathyroid hormone(PTH), growth hormone(GH)과 25-hydroxyvitamin D(25(OH)D)를 분석하였다. 그룹 간 태권도 트레이닝 전·후 종속변인의 차이를 규명하기 위해 반복 이원분산분석을 적용하였고, 그룹 내 차이는 대응 t-검정을 이용하여 분석하였다. 골밀도와 뼈나이, 체중, 신장, 골 건강관련 호르몬의 관계를 규명하기 위해 다중회귀분석을 적용하였다. 이 연구 결과 훈련군의 전신 골밀도(p<.001), 요추 골밀도(p<.001), 전완 골밀도(p<.01)는 12주 태권도 트레이닝 전·후 통계적으로 유의하게 증가하였으나 통제군은 유의한 변화가 없었다. 한편 대퇴 골밀도는 훈련군과 통제군 모두 12주 트레이닝 전·후 유의한 변화가 나타나지 않았다. OC는 훈련군(pre: 13.18ng/mL, post: 40.38ng/mL)과 통제군(pre: 13.04ng/mL, post: 40.89ng/mL) 모두 통계적으로 유의하게 증가한 반면, CC는 두 그룹 모두 유의한 변화가 없었다. PTH는 훈련군의 경우 통계적으로 유의하게 감소하였지만(p<.05), 통제군은 유의한 차이를 보이지 않았다. GH는 트레이닝 전·후 훈련군과 통제군에서 유의한 상호작용효과가 나타났으며(p<.05), 훈련군(pre: 0.70ng/mL, post: 4.22ng/mL)에서는 증가한 반면 통제군(pre: 5.40ng/mL, post: 2.04ng/mL)에서는 감소하였다. 25(OH)D는 훈련군과 통제군 모두 통계적으로 유의하게 감소하였다. 골밀도의 예측변인을 분석한 결과 훈련군에서 전신 골밀도의 경우 뼈나이, 제지방조직, 신장이 높은 설명력을 보였고, 요추 골밀도의 경우 뼈나이, 전완 골밀도의 뼈나이, PTH, 생활나이가 유의한 설명력을 나타냈다. 결론적으로 12주간의 태권도 트레이닝은 남자 청소년들의 골밀도와 골 건강관련 호르몬에 긍정적인 영향을 미친 것으로 나타났으며 태권도 트레이닝이 청소년들의 요추 골밀도에 영향을 미치기 위해서는 12주 이상의 장기간의 훈련을 통한 후속연구가 필요할 것으로 사료된다.

Comparison of Quality Characteristics and Palatability between Sous-Vide Cooked Pork Loin Patties with Different Searing Treatments

Cho, Dong Kook,Lee, Boin,Kim, Song Ki,O, Hyeonbin,Kim, Young Soon,Choi, Young Min Korean Society for Food Science of Animal Resource 2021 한국축산식품학회지 Vol.41 No.2

This study compared the quality, cooking, textural, and palatability characteristics between sous-vide (SV) cooked pork loin patties with different searing treatments (ST). Before SV cooking, STs were conducted on each side of the pork loin patties for 0 (control) to 120 s (ST120), and all patties were then cooked using an SV cooker at 75℃ for 120 min. Noticeable differences were observed in quality properties between the groups. The seared SV loin patties exhibited lower lightness and higher browning index values compared to the unseared SV loin patties (p<0.001). Cooking loss gradually increased with increasing ST times, and the control group had a lower percentage compared to the ST60 group (19.5 vs. 25.7%, p<0.001). Changes in cooking properties were associated with the extent of ST, and the ST groups exhibited a higher hardness value compared to the control group (p<0.001). Regarding palatability, loin patties from the control group scored lower in appearance acceptability compared to patties from the ST groups (p<0.05) due to extent of browning on the surface. Moreover, the ST groups did exhibit a higher flavor intensity compared to the control group, but no differences were observed in tenderness and juiciness scores between the control and ST60 groups. Due to these results, the ST60 group exhibited a greater score in overall acceptability compared to the other groups except for the ST90 group. Therefore, an additional ST before SV cooking can achieve a more appealing appearance and palatability as well as to enhance the availability of pork loin.

Bifidobacterium angulatum으로부터 α-galactosidase의 정제 및 특성

강대중,민해기,강국희 成均館大學校 科學技術硏究所 1993 論文集 Vol.44 No.1

α-galactosidase는 (α-D-galactoside galactohydrolase: EC 3.2.1.22)는 다당류나 올리고당인 melibiose, raffinose, stachyose와 guar gum 등의 α-galactosidic 결합을 하고 있는 당을 분해하는 효소이다. 장내세균중 우익균이며 우세균주인 Bifidobacteria로부터 α-galactosidase의 효소학적 특성을 알아보기 위하여 배양여액으로부터 ammonium sulfate분획, 핵산의 제거, Sephadex G-200 gel filtration 및 DEAE-Sephadex A-50 ion exchange chromatography 등의 4단계 정제과정을 거쳐 정제한 결과 약 8배로 정제되어 단일 단백질로 분리하였다. 또한, 효소분해산물을 알아보기 위하여 TLC에 의하여 당분해 및 올리고당의 생성을 알아보았다. 정제효소의 활성 최적온도는 37℃, 최적 pH는 7.0이었다. 효소활성이 K^+, Zn^2+과 같은 금속이온과 8-Hydroxyquinoline, Sodium Bisulfite 등에 의해선 그다지 저해되지 않았으나, Hg^+, Cu^2+과 p-Chloromercuribenzoic acid에 의해선 저해되었다. 효소의 분자량이 301, 995, 합성기질인 PNPG에 대한 K_m은 0.069mM, V_max는 347.22μmol/min.mg protein이었다. To elucidate enzymatic properties of α-galactosidase (EC 3.2.1.22) from Bif.angulatum. α-galactosidase was purified to homogeneity by ammonium sulfate fractionation, protamine sulfate precipitation, sephadex G-200 gel filtration, and DEAE-sephadex A-50 ion exchange chromatography. The purified α-galactosidase was found tobbe homogeneous by SDSpolyacrylamide gel electrophoresis. The molecular weight of this enzyme, estimated by sepadex G-200 gel filtration, was about 301,995. The optimum conditions for the enzyme reaction was pH 6.5 to 7.0 at 37℃. The purified enzyme was stable at 45℃ or below and in buffer at pH 6 to 7.0. The activity was inhibited by mercury, copper ion, and p-chloromercuribenzoic acid. The kinetics of this enzyme, with p-nitrophenyl-α-D-galactoside as substrate, was determined : K_m was about 0.069mM and V_mas was 347.22 μmoles/min mg protein.

C -11 및 F - 18 표지 콜린의 합성과 체내동태에 관한 연구

전권수,유국현,김상욱,임상무,홍성운,서용섭,양승대,안순혁,허민구 대한핵의학회 2001 핵의학 분자영상 Vol.35 No.3

Objectives: Recently, [methyl-(11)^C]-(β-Hydroxyethyl)trimethylammonium ([(11)^C]choline) has been discovered to be a very effective tracer in imaging various human tumors using positron emission tomography. Because of the short half-life of C-11, it is very difficult to use in a routine imaging procedure and needs a frequent synthesis of [(11)^]choline. This can be supplemented by the substitution of [(11)^Ccholine with [methyS-18]fluorocholine. Here, we would like to report cell uptake and biodistribution of [(11)^Ccholine and [(18)^F]fluorocholine as a basic study. Methods [(11)^C]Choline was prepared by the treatment of [(11)^C]CHzI with N,N-dimethylaminoethanol and [18F]fluorocholine was synthesized from reaction of CHzBr[18F]F with N,N-dimethylaminoethanol. The radiochemical purity was checked by high performance liquid chromatography (HPLC). The biodistribution of [(11)^C]choline and [(18)^F]fluorocholine was determined in balb/c mouse at 5 min, 20 min, 40 min and 80 min. The cell uptake wa measured using glioma (9L) and colon adeocarcinoma (SW620). Results: The radiochemical purity was more than 98% after purification. In the liver, uptake did not change over time the uptake was 20/ID/g for [C]choline and 13%ID/g for [(18)^F]fluorocholine. In the kidney, radioactivity decreased over tirne the uptake was 15%1D/g for [(11)^Ccholine and 20%ID/g for [(18)^F]fluorocholine, 80 min post-injection. The cell uptake of [(11)^Ccholine was 4.93% for glioma (9L) and 18.69F for colon adenocarcinoma (SW620). For [(18)^F]fluorocholine, 1.77% for glioma (9L) and 2.77% for colon adenocarcinoma (SW620). Conclusion: [(11)^CCholine and [(18)^F]fluorocholine showed a different cell uptake tendency, depending on cancer cell line. (Korean J Nucl Med 200135:185-191)

가토에서 Vecuronium bromide 의 용량에 따른 근육이완 효과

김동원,이동호,민경호,전세웅,유희구,김경헌,승익상,김교상,서정국 대한마취과학회 1987 Korean Journal of Anesthesiology Vol.20 No.6

The introduction of muscle relaxants was an epoch making event in the development of clinical anesthesia and their use has hecame essential to anesthesia practice. Vecuronium, one of the newest muscle relaxants, many advantages; it is .apid acting, non-accumulating, has minimals side reactions and is promptly antagonized by anticholinesterases. However, its pharmacological effect, like other conventional muscle relaxants depends upon the dose and is influenced br many factors including body temperature, blood flow, interaction with other drugs, antibiotics, diuretics and so forth, To obtain a dose·response relationship which is important for clinical use, the effect of the vecuronium in various doses on the neuromuscular block in rabbits was investigated. The results were as follows. 1) In the vecuronium 0.025 mg/kg group, maximal twitch depression was varied between 75 to 92% with a mean value of 84,9%. The spontaneous recovery index was 141.0 seconds (2.35 min). 2) In the vecuranium 7.75 mg/kg group, thmean maximum twitch depression and spontaneous recovery index were 98.4% and 218.6 seconds (3.64 min.) respectively. 3) In the vecuronium 7.1 mg/kg group, maximum twitch depression was 100% and the spontaneous recovery index was markedly prolonged to 627.8 seconds (10.35 min).

Korean physician prescription patterns for home oxygen therapy in chronic obstructive pulmonary disease patients

( Youlim Kim ),( Hwan Il Kim ),( Ji Young Park ),( Ji Young Hong ),( Joo-hee Kim ),( Kyung Hoon Min ),( Chin Kook Rhee ),( Sunghoon Park ),( Chang Youl Lee ),( Seong Yong Lim ),( Seung Hun Jang ),( Yo 대한내과학회 2022 The Korean Journal of Internal Medicine Vol.37 No.1

Background/Aims: Hypoxemia in chronic obstructive pulmonary disease (COPD) leads to reduced ability to exercise, decreased quality of life, and, eventually, increased mortality. Home oxygen therapy in patients with severe COPD reduces distress symptoms and mortality rates. However, there have been few studies on physicians’ prescription behavior toward home oxygen therapy. Therefore, we investigated the respiratory specialists’ perspective on home oxygen therapy. Methods: In this cross-sectional, study, a questionnaire was completed by 30 pulmonary specialists who worked in tertiary hospitals and prescribed home oxygen therapy. The questionnaire consisted of 28 items, including 15 items on oxygen prescription for outpatients, four for inpatients, and nine on service improvement. Results: All physicians were prescribing less than 2 L/min of oxygen for either 24 (n = 10, 33.3%) or 15 hours (n = 9, 30.3%). All (n = 30) used pulse oximetry, 26 (86.7%) analyzed arterial blood gas. Thirteen physicians had imposed restrictions and recommended oxygen use only during exercise or sleep. Sixteen (53.3%) physicians were educating their patients about home oxygen therapy. Furthermore, physicians prescribed home oxygen to patients that did not fit the typical criteria for long-term oxygen therapy, with 30 prescribing it for acute relief and 17 for patients with borderline hypoxemia. Conclusions: This study identified the prescription pattern of home oxygen therapy in Korea. Respiratory physicians prescribe home oxygen therapy to hypoxemic COPD patients for at least 15 hours/day, and at a rate of less than 2 L/ min. More research is needed to provide evidence for establishing policies on oxygen therapy in COPD patients.

Bifidobacterium longum KCTC 3215의 β-Galactosidase 유전자의 Cloning 및 대장균에의 발현

민해기,강국희,성문희 成均館大學校 科學技術硏究所 1992 論文集 Vol.43 No.2

The β-D-galactosidase(β-gal) gene from Bifidobacterium longum KCTC 3215 was cloned to isolate and characterize it for potential use as a selection marker in food-grade cloning vector. Chromosomal DNA from Bif. longum KCTC 3215 was cleaved with the restriction enzyme Sau3AI and ligated to pBR 322 for transformation into E. coli JM109. A β-galactosidase positive clone was detected by its blue color on a medium supplemented with 5-bromo-4-chloro-3-indolyl-β-D-galactoside. This transformant possessed a single plasmid, designated pSK 100, which contained, in addition to the vector DNA, a 5.2 Kilobase(Kb) Sau3A1 insertion fragment coding for β-gal activity. An extract from JM 109(pSK100) contained a β-gal protein with the same electrophoretic mobility as the β-gal from Bif. longum KCTC 3215. A restriction enzyme map of pSK 100 was consisted of PvuII, HincII, PstI,AccI, EcoRI, etc.

지리 교과에서 동영상 자료의 활용과 그 효과에 관한 연구

국민정 한국지리환경교육학회 2003 한국지리환경교육학회지 Vol.11 No.3

본 연구는 지리 교과에 적합한 동영상 학습 자료를 활용한 수업을 기획하고 실시하여 효과를 밝히는 데 그 목적이 있다. 동영상 학습 자료는 영상과 더불어 음향에 의한 자극까지 더해지기 때문에 인쇄 매체나 다른 매체를 수업에 활용할 때보다 학습자의 주의 집중력, 설명 능력, 기억 유지 능력 등을 함양시킬 수 있는 기능을 지니고 있다. 동영상 학습 자료가 수업 상황에서 제대로 활용되기 위해서 학생들의 요구가 무엇인지, 학습 목표나 내용은 무엇인지, 사용할 교수 방법은 어떠한 것인지 등이 사전에 잘 고려될 때 동영상 자료의 효과를 극대화시킬 수 있다. 지리 교과 내용에 적합한 동영상 자료를 선정한 후, 동영상 자료를 활용한 지리 수업을 기획하였다. 학습자들은 지리 수업에서 동영상 자료가 지속적으로 사용되기 원하고 있고, 지리 교육에서 동영상 자료를 활용하는 것은 학업 성취도를 높여주고, 가치판단력을 향상시키며, 교과에 대한 흥미도를 증가 시켜 여러 상승 효과를 불러일으킬 수 있으므로, 지리교과에 적합한 다양한 동영상 학습 자료의 개발 및 수업 설계가 더욱 필요하다고 하겠다. The purpose of this study is to work out a teaching program using various motion picture learning materials which are proper for geography subject and to reveal the effects of this teaching method. Motion picture learning materials are more effective than any other ones in that they can improve the students’ concentration, understanding and retentive faculty very effectively. To make the best of motion picture materials in geography class, the needs of the students, the purpose and contents of the class, and the teaching methods should be well considered. In order to attain the purpose of the study, the researcher select the news materials proper for geography class and design the class using these materials. Using motion picture materials in geography class is a very excellent way to improve the students’ learning achievement level and value judgement ability while increasing the interest in geography subject. In addition, students want the motion picture materials to be constantly used in the class. Therefore, constant and earnest efforts to find out various motion picture materials for geography subject and to work out a teaching program using these materials should be made.