• Journal of Electrochemical Science and Technology
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• 제13권1호
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• pp.78-89
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• 2022

ANODE-free Li-metal batteries (AFLMBs) operating with Li of cathode material have attracted enormous attention due to their exceptional energy density originating from anode-free structure in the confined cell volume. However, uncontrolled dendritic growth of lithium on a copper current collector can limit its practical application as it causes fatal issues for stable cycling such as dead Li formation, unstable solid electrolyte interphase, electrolyte exhaustion, and internal short-circuit. To overcome this limitation, here, we report a novel dual-salt electrolyte comprising of 0.2 M LiPF₆ + 3.8 M lithium bis(fluorosulfonyl)imide in a carbonate/ester co-solvent with 5 wt% fluoroethylene carbonate, 2 wt% vinylene carbonate, and 0.2 wt% LiNO₃ additives. Because the dual-salt electrolyte facilitates uniform/dense Li deposition on the current collector and can form robust/ionic conductive LiF-based SEI layer on the deposited Li, a Li/Li symmetrical cell exhibits improved cycling performance and low polarization for over 200 h operation. Furthermore, the anode-free LiFePO₄/Cu cells in the carbonate electrolyte shows significantly enhanced cycling stability compared to the counterparts consisting of different salt ratios. This study shows an importance of electrolyte design guiding uniform Li deposition and forming stable SEI layer for AFLMBs.

• Journal of Korean Neurosurgical Society
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• 제30권sup2호
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• pp.259-265
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• 2001

Objectives : Spontaneous intracerebral hemorrhage(S-ICH) is generally considered to be a mon-ophasic event. But some patients with ICH continued to bleed even after hospitalization. In order to evaluate the rebleeding and growth factor of hematoma in small volume S-ICH, 125 cases of S-ICH were reviewed retrospectively. Methods : We assesed age, sex, initial mental state, location of hemorrhage, systolic and diastolic blood pressure, blood pressure patterns, hematologic profile, trauma and stroke history, alcohol consumption and smoking history. Two subgroups-rebleeding groups versus no rebleeding groups-were compared, in terms of data analysis, with student T-test and chi-square test. Results : Substantial growth in the volume of S-ICH occurred in 21 cases(16.8%)-putamen(7 cases), thalamus(6 cases), subcortex(5 cases), cerebellum(2 cases), pons(1 case)-of the 125 patients. There was no significant difference in any of the parameters except initial systolic blood pressure(p=0.037) when patients with and without rebleeding were compared. Conclusion : The rebleeding and growth of the small volume S-ICH was related to the markedly elevated initial systolic blood pressure(${\geq}180mmHg$) and labile pattern of blood pressure.

• 한국세라믹학회지
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• 제54권3호
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• pp.249-256
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• 2017

We design Ge-Al multilayer assemblies as anode materials for Li-ion batteries, in which Ge and Al thin films are alternately deposited by a radio sputtering method. By sandwiching Ge layers between Al layer, the cyclability, rate capability, and capacity of Ge are improved significantly. The success of the Ge-Al multilayer is attributed to the Al films. To maintain the integrity of electrical contact, Al acts as an elastic layer, which can expand or shrink with the Ge film upon lithiation or delithiation. In addition, the presence of the Al film on the surface can prevent direct contact of Ge and electrolyte, thereby reducing the growth of a SEI layer. Importantly, with high electrical and ionic conductivities, the Al film provides efficient electrical and ionic routes for electrons and Li-ions to access the Ge film, promoting a high specific capacity and high rate capability for Ge.

• 한국결정성장학회지
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• 제21권1호
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• pp.15-20
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• 2011

[ $^7Li$ ]Magic Angle Spinning(MAS) NMR Spectroscopy를 활용하여 $Li_4P_2O_7$와 $LiFePO_4$ 물질에서 $^7Li$ 핵의 NMR 특성 및 화합물 분자내의 국부적 구조 연구를 수행하였다. $Li_4P_2O_7$와 $LiFePO_4$ 물질 연구는 리튬이온전지에서 고체-전해질 경계상(SEI, solid-electrolyte interphase) 물질 연구를 위한 것이다. $Li_4P_2O_7$와 $LiFePO_4$ 분말은 고상합성법으로 제조하였다.$^7Li$MAS NMR 실험은 $27^{\circ}C$에서 $97^{\circ}C$의 영역에서 변온 실험을 수행하였으며 이는 주변 온도 변화 환경에서 $Li_4P_2O_7$ 물질 내의 Li 핵의 구조 변화를 관찰하기 위한 것이다. $^7Li$ MAS NMR 측정 결과 시료 온도가 $27^{\circ}C$에서 $97^{\circ}C$의 온도 분포 영역에서는 $Li_4P_2O_7$ 물질 내부의 Li 핵은 구조적으로 변화하지 않는 것이 확인되었다. 금번 실험을 통하여 $LiFePO_4$ 분말에 5.0 wt%이내로 포함되어있는 $Li_4P_2O_7$ 물질의 $^7Li$ MAS NMR 신호를 측정할 수 있는 측정 조건을 알았다.

• 한국초지조사료학회지
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• 제30권1호
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• pp.9-14
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• 2010

본 시험은 논에서 벼 대체 여름 사료작물인 수수류를 논 재배하여 생육특성과 수량에서 우수한 품종을 선발할 목적으로 2008년부터 2009년까지 2년간에 걸쳐 충남 천안 농가 포장에서 수행하였다. 도입품종인 수수류 10품종 중에서 'Sordan79'는 습해에 비교적 강하고 2차 재생이 잘되며 당도가 높고 병해와 충해에 강한 생육특성을 보였고 수량 측면에서도 생초수량이 ha당 92,492 kg, 건물수량이 21,090 kg으로 가장 우수한 품종이었다. 따라서 본 연구결과를 토대로 볼 때 중부지역에서 벼 대체 사료작물인 수수류를 논에 재배 할때는 배수가 양호한 논의 선정이 필요하고 수수류 품종 중에서는 'Sordan79'를 재배하는 것이 적응성이나 생산성 측면에서 가장 유리하다고 할 수 있다.

• Clinical and Experimental Pediatrics
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• 제53권10호
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• pp.892-897
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• 2010

Purpose: This study evaluated the prevalence of the metabolic syndrome (MetS) and risk factors for metabolic derangement in young adults with childhood-onset hypopituitary growth hormone deficiency (ACOHGHD). Methods: Thirty patients with ACOHGHD who were treated with hormone-replacement therapy, aged 18 to 29 years, who visited the Seoul National University Children's Hospital between September 2009 and February 2010 were enrolled. Height, weight, waist circumference, hip circumference, and blood pressure were measured, and the clinical and hormonal features were reviewed retrospectively. We evaluated measures of metabolic derangement in the enrolled patients and in the data of healthy adults aged 20 to 29 years taken from the 2005 Korean National Health and Nutrition Examination Survey (KNHANES) as part of the National Cholesterol Education Program-the Adult Treatment Panel III. Results: Compared with the KNHANES participants, patients with ACOHGHD had significantly large waist circumference (men and women), high systolic blood pressure (BP) (women) and diastolic BP (men), and high serum triglyceride levels (women). The duration of illness correlated significantly with central obesity ($r^2$=0.546, $P$=0.003). The prevalence of MetS was 10% in patients with ACOHGHD and 2.3% in KNHANES participants. The prevalence of central obesity and MetS was higher in patients with ACOHGHD than in KNHANES participants ($P$<0.001 and $P$=0.042, respectively). Conclusion: Abdominal obesity correlated with the duration of illness in patients with ACOHGHD. Waist circumference should be measured in the clinic to prevent MetS, particularly in patients with a long history of ACOHGHD, regardless of age or sex.

• Journal of Plant Biotechnology
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• 제30권2호
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• pp.201-206
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• 2003

Differential responses of red pepper plant and cultured cells to enhanced ${\gamma}$-ray($^{60}$ Co) and ultraviolet(UV) stress were investigated. In seed treatment, 1 Gy of ${\gamma}$-ray increased seedling dry weight up to 19.1%, but 50 Gy treatment markedly ingibited seed germination and subsequent growth of seedling. UV treatment to seed did not change the germination ability of seeds and the growth of seedlings regardless of duration of UV treatment until 24 hrs. In case of UV treatment to seedlings, plant injury was seriously progressed even after the seedlings were returned to no UV condition, and eventually all the leaves showed chlorosis by the stress. However, progress of plant injury by ${\gamma}$-ray stress slower than that caused by UV stress, and even at the high dose of ${\gamma}$-ray 50 Gy, did not caused the cholrosis of stressed plant leaf. Amount of electrolytes leakage from plant leaf by UV treatment for 24hrs was increased up to 28.8 folds in comparison with untreated control, whereas that of 50 Gy of ${\gamma}$-ray was increased only 1.2 folds. UV stress induced the production of capsidiol, antimicrobial phytoalexin, by activation of gene expression involved in capsidiol biosynthesis, such as sesquiterpene cyclase and cyclase and cytochrome P450 hydroxylase in the leaf and cultured cell, but ${\gamma}$-ray stress induced neither the production of capsidiol nor expression of the genes.

• Radiation Oncology Journal
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• 제3권1호
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• pp.19-28
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• 1985

Twenty-four cases of pituitary adenoma, 13 males and 11 females with the age ranging from 11 to 65 years, received radiation therapy(RT) on the pituitary area with 6MV linear accelerator during past 25 months at the Division of Radiation Therapy, Kangnam St. Mary's Hospital, Catholic Medical College. Of 24 cases of RT, 20 were postoperative and 4 primary. To evaluate the effect of RT, we analysed the alteration of the endocrinologic tests, neurologic abnormalities, major clinical symptoms, endocrinologic changes and improvement in visual problems after RT. The results were as follows ; 1. Major clinical symptoms were headache, visual defects, diabetes insipidus, hypogonadisms and general weakness in decreasing order of frequency. 2. All but the one with Nelson's syndrome showed abnormal neuroradiologic changes in the sella turcica with an invasive tumor mass around supra· and para-sellar area. 3. Endocrinological classifications of the patient were 11 prolactinoma, 4 growth hormone -secreting tumors, 3 ACTH-secreting tumors consisting of one Cushing's disease and two Nelson's syndrome, and 6 nonfunctioning tumors. 4. Eleven of 14 patients, visual problems were improved after treatment but remaining 3 were unchanged. 5. Seven of 11 prolactinomas returned to normal hormonal level after postoperative and primary RT and 3 patients are being treated with bromocriptine (BMCP) but one lost case. 6. Two of 4 growth hormone·secreting tumor returned to normal level after RT but the remaining 2 are being treated with BMCP, as well.

• 한국작물학회지
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• 제50권1호
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• pp.11-15
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• 2005

This experiment was conducted to investigate the changes of growth and maturity and to clarify the function of supernodulating characters, excessive nodules and high biological nitrogen fixation rate (BNF), on maturity in response to different planting time in supernodulating soybean mutants. Two supernodulating soybean mutants, Sakukei4 and SS2-2, and their parent cultivars, Enrei and Shinpaldalkong2, were planted on May 24 and June 15, 2004. The degrees of the shortening of growth days by the planting time delay were 18 to 22 days in four cultivar, and there were no significant differences among the cultivars. However, four cultivars showed the different maturity properties. Sakukei4, mutated from Enrei, showed later maturity than that of Enrei, and 882-2, mutated from Shinpaldalkong2, showed earlier maturity than that of Shinpaldalkong2. The plant and nodule dry weights at R6 stage of Sakukei4 showed the smallest decrement and those of SS2-2 was showed the largest decrement by the delay of planting time. The photosynthetic rates of Sakukei4 during the late reproductive growth period were slowly decreased, however those of SS2-2 were steeply decreased in two planting time treatments. Overall, the growth of Sakukei4 was decreased slowly, however the growth of SS2-2 was decreased sharply according to the delay of planting time. The percentage of seed yield of Sakukei4 in June planting plot compared with May planting plot at R8 stage was $92\%$, which was the lowest decreasing rate of yield among the cultivars, and in the case of SS2-2, it was in $76\%$, the highest one. These results indicated that the responses of supernodulating mutants by the delay of planting time were very similar to the wild types. This means supernodulating characters in supernodulating soybean mutants might not affect to the maturity property. Additionally, the maturity property could be considered as an important characteristics to decide or to select on the developments of supernodulating soybean mutants, which have a low productivity by an excessive nodules, especially.

• 한국작물학회지
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• 제50권1호
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• pp.5-10
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• 2005

This experiment was conducted to clarify the functions of supernodulating characters on seed yield determination through the comparison of agricultural traits of supernodulating soybean mutants, Sakukei4, SS2-2, and their parent cultivars, Enrei and Shinpaldalkong2. The plant dry weights of supernodulating mutants, Sakukei4 and SS2-2, were $52\%$ and $61\%$ of their wild type parents at full seed stage (R6). However, the relative growth rate (RGR) from the pod set stage (R3) to R6 of Sakukei4 was 0.022 g/g/day and that of SS2-2 was 0.016 g/g/day, which were higher than those of their parents. Nodule number and dry weight were increased in two supernodulating mutants by the R6 stage. The nitrogen concentrations of leaf, petiole and stem of Sakukei4 were higher than those of Enrei. SS2-2 showed higher nitrogen concentration in petiole than Shinpaldalkong2 had. The positive correlations were appeared between nodule dry weight, plant dry weight and pod number, in two supernodulating mutants during the period from R3 to R6 stage. Although all of the yield components and seed yield were lower in two supernodulating mutants than their parents at the stage of full maturity (R8), the harvest index was higher in supernodulating mutants. The increasing rates of pod number to stem dry weight in two supernodulating mutants showed the higher than those of two their parents at R8 stage. In conclusion, the relative growth rates during the early to the middle reproductive growth period were higher in supernodulating mutants than the wild types. This could be resulted in an increase in pod number. The increase of relative growth rate was the result of the successive supplement of nitrogen source from biological nitrogen fixation (BNF) of nodules during the middle reproductive growth period in supernodulating mutants.