The structure of nitrogen adsorption complex of fully dehydrated Cd2+ ion exchanged zeolite-X, |Cd46(N)18|[Si100Al92O384], was determined in the cubic space group Fd3 at 21(1) ℃ [a = 24.863(4) ] by single crystal X-ray diffraction analysis. The crystal was prepared by ion exchange in a flowing steam of 0.05 M aqueous solution Cd(NO3)2 : Cd(O2CCH3)2 = 1:1 for five days, followed by dehydration at 500℃ and 2×10-6 Tor. for two days, and exposured to 100 Tor. zeolitically dry nitrogen gas at 21(1) ℃. The structure was determined in atmosphere, and was refined within F0 〉 4Σ(F0) using reflection for which the final error can appear in indices R1 = 0.097 and wR2 = 0.150. In this structure, Cd2+ ions occupied four crystallographic sites. Nine Cd2+ ions filled the octahedral site I at the centers of hexagonal prisms (Cd-O = 2.452(16) a). Eight Cd2+ ions filled site I' (Cd-O = 2.324(19) a). The remaining 29 Cd2+ ions are found at two nonequivalent sites II (in the supercages) with occupancy of 11 and 18 ions. Each of these Cd2+ ions coordinated to three framework oxygens, either at 2.159(15) or 2.147(14) a, respectively. Eighteen nitrogen molecules were adsorbed per unit cell and three per supercage.

캘리포오니아 홍합(Mytilus californianus)의 용존 Cd, Se, Zn의 흡수율에 대한 개체 크기와 수온의 영향을 평가하기 위하여 방사성 동위원소를 이용한 실험을 수행하였다. 세 개의 크기 구배(0.07, 0.24 and 0.73g; 육질부 건중량)를 갖는 홍합의 용존 금속 흡수율과 여수율은 동시에 4개의 온도 구배(3, 8, 13 and 21˚C)에서 측정되었다. 세 원소의 흡수율은 개체 크기가 증가함에 따라 유의하게 감

Research has shown that using multimedia teaching materials such as movie videos and CD-ROMs in foreign language classrooms has been effective. The purpose of the present study is to investigate the effects of using a movie CD-ROM in English classrooms as a way of improving English language skills and enhancing students’ positive perception of learning English. Sixty 10th-grade students in a commercial high school participated in the study which lasted 10 weeks. One group used the movie Big, while the other group used the conventional method of listening to a tape that accompanied a textbook. The data, which were analyzed statistically using the SPSS, showed the following results: 1) Even though the experimental group’s level of interest and confidence increased by using the movie CD-ROM, the increase was not statistically significant. The same can be said for the control group. 2) The experimental group showed a statistically significant improvement in vocabulary building, while the control group did not. 3) Neither group showed significant improvement in terms of listening ability.

수경 재배된 케냐프의 중금속 축적량 및 제거량을 파악하고 서로의 관계를 도출하기 위하여 Cd, Cu, Cr, Ni 및 Zn이 포함된 반응조에 노출시켰다. 대상식물의 최적성장을 위한 pH, DO, 전도도 및 영양염의 농도조절은 액체비료를 이용하여 조정하였다. 8일의 수리학적 체류시간을 적용했을 때 Cr, Cd, Cu, Ni 및 Zn의 제거율은 각각 90.5%, 80.5%, 66.1%, 71.1% 및 79.4%였고 그 농도는 각각 2.34에서 0.54 mg

3주간 정상적으로 생장한 닭의장풀을 Hoagland용액 (± 100 μM Cd2+, 100 μM Cd2++10 μM IAA,100 μM Cd2++100 μM IAA,100 μM Cd2+ +1 μM IAA)에서 3주간 수경재배 한 후 생장, 기공개폐, 엽록소 함유량, 엽록소 형광 및 수분퍼텐셜을 조사하였다. Hoagland용액에 Cd2+ 처리시 3주 동

3-weeks old Commelina was transferred to and grown in Hoagland solution (± 100 μM Cd2+, 100 μM Cd2+ ＋ 100μM Ca2+, 100 μM Cd2+ ＋ 200 μM EGTA) for two weeks and then a number of physiological activities

2001년 1-12월 서울시 가락농수산물시장에서 총 951건의 수산물(어류 34종 468건, 패류 17종 373건, 갑각류 10종 39건 그리고 두족류 등 11종 71건)을 대상으로 중금속 함량[average(minimum∼maximum), Unit:㎎/㎏]을 분석한 결과, Hg 0.025(N.D.∼0.19), Cd 0.288(N.D.∼1.85), pb 0.227(ND∼1.68)이었다. Hg의 경우, 패류[0.003((N.D.∼0.19)]>두족류 등[0.026(N.D.∼0.11)]>갑각류[0.026(N.D.∼0.09)]>어류[0.018(N.D.∼0.19)]순이었고, 가장 높은 함량은 미꾸라지(0.19)와 꼬막(0.19)이었으며, Pb의 경우 패류[0.223(N.D.∼1.38)]>어류[0.213(N.D.∼1.68)]>두족류 등[0.151(N.D.∼0.39)>갑각류[0.144(N.D.∼0.44)]순이었고, 가장 높은 함량은 미꾸라지(1.68)>빙어(1.44)>바지락(1.38)>뱀장어(1.35) 순이었다. 한편, Cd의 경우 패류[0.288(N.D.∼1.85)]중 가장 높은 함량은 꼬막(1.85)이었다.

This study was concentrated that the contents of heavy metals were estimated from 782 samples of sold fisheries in Seoul(33 species in fishes, 15 in bivalves, 12 in crustaceans and 10 in others) by Atomic Absorption Spectrometer. The contents of As, Cd and Pb [minimum-maximum (mean)] were N.D.-0.162 mg/kg(0.021), 0.001-0.120 mg/kg(0.014) and 0.015-0.499 mg/kg(0.111) in fishes, 0.003-0.311 mg/kg(0.052), N.D.-1.905 mg/kg(0.182) and 0.013-0.462 mg/kg(0.138) in bivalves, N.D.-0.328 mg/kg(0.042), 0.002-1.113 mg/kg(0.079) and 0.006-0.510 mg/kg(0.109) in crustaceans, N.D.-0.181 mg/kg(0.024), 0.001-0.214 mg/kg(0.033) and 0.010-V0.877 mg/kg(0.118) in others respectively, bivalves were the highest than others. The average weekly intakes of three metals from sold fisheries took about 1.4-26.4% of PTWI (provisional tolerable weekly intakes) that FAO/WHO Joint Food Additive and Contaminants Committee had set to evaluate their safety.

Al-Cu-Mn 주조합금의 피로성질에 미치는 Cd 첨가의 영향을 저주기 및 고주기 피로시험을 통하여 조사하였다. Cd 첨가량이 증가함에 따라 피로수명이 증가하였으며, 인장강도도 증가하였다. 고주기 피로시험결과 피로강도는 115MPa이었으며 피로비는 0.31이었다. 피로시험 결과 균열이 표면에서 발생하여 입계를 따라 전파되었는데 이러한 입계파괴는 입계를 따라 존재하는 무석출대의 영향으로 생각된다. 인장강도값은 Cd이 첨가되지 않았을 경우 330MPa이었으나 0.15%의 Cd이 첨가됨으로써 401MPa 까지 증가되었다.