Effect of oxidizing treatment on electrocatalytic activity of boron-doped amorphous carbon thin films

Wang Chen-Song,Suo Ni,Huang Hao,Wu Ai-min,Cao Guo-Zhong,Zhang Gui-Feng 한국탄소학회 2019 Carbon Letters Vol.29 No.5

Boron-doped amorphous carbon (BDAC) thin films with a regular oxygen reduction reaction (ORR) catalytic activity were synthesized in a hot filament chemical vapor deposition device using a mixture of CH4 and H2 as a gas source and B2O3 as a boron source and then oxidized in air at 380–470 °C for 15–75 min. Scanning electron microscope, transmission electron microscope, Raman spectroscopy, X-ray photoelectron spectroscopy, and electrochemical tests were used to characterize the physical and electrochemical properties of the BDAC catalysts. It was concluded that the BDAC catalyst oxidized at 450 °C for 45 min showed the best ORR catalytic activity in alkaline medium. The oxygen reduction potential and the transfer electron number n, respectively, are − 0.286 V versus Ag/AgCl and 3.24 from the rotating disk electrode experiments. The treated carbon film has better methanol resistance and stability than the commercial Pt/C catalyst.

Effect of oxidizing treatment on electrocatalytic activity of boron‑doped amorphous carbon thin films

Chen‑Song Wang,Ni Suo,Hao Huang,Ai‑min Wu,Guo‑Zhong Cao,Gui‑Feng Zhang 한국탄소학회 2019 Carbon Letters Vol.29 No.5

Boron-doped amorphous carbon (BDAC) thin films with a regular oxygen reduction reaction (ORR) catalytic activity were synthesized in a hot filament chemical vapor deposition device using a mixture of CH4 and H2 as a gas source and B2O3 as a boron source and then oxidized in air at 380–470 °C for 15–75 min. Scanning electron microscope, transmission electron microscope, Raman spectroscopy, X-ray photoelectron spectroscopy, and electrochemical tests were used to characterize the physical and electrochemical properties of the BDAC catalysts. It was concluded that the BDAC catalyst oxidized at 450 °C for 45 min showed the best ORR catalytic activity in alkaline medium. The oxygen reduction potential and the transfer electron number n, respectively, are − 0.286 V versus Ag/AgCl and 3.24 from the rotating disk electrode experiments. The treated carbon film has better methanol resistance and stability than the commercial Pt/C catalyst.

우문맥과 좌문맥 사이의 종속성에 관한 연구

정민수,김우완 慶南大學校 附設 工業技術硏究所 1997 硏究論文集 Vol.14 No.2

구문 오류의 보정이나 점진적 구문 분석에 사용되는 우문맥의 계산은 일반적으로 좌문맥에 의존하는 것으로 알려져 있다. 최근 본 연구자는 우문맥의 효율적인 계산 방법을 연구하는 과정에서 대부분의 경우 우문맥이 좌문맥에 독립적이라는 사실을 찾아냈다. 이 사실은 우문맥의 계산의 시점이 좌문맥이 결정되는 실행 시간에 계산될 필요 없이 번역 시간에 미리 계산 될 수 있어서 실행 시간의 단축이 가능함을 의미한다. 본 논문에서는 실제 몇 가지 프로그래밍 언어에 대하여 번역 시간에 미리 계산 가능한 우문맥을 찾아냄으로써 대부분의 경우 우문맥이 좌문맥에 독립적이라는 사실을 입증 하였다. Right contexts may be used in syntax error repair or incremental parsing. It is well known that right contexts depends upon left contexts. We have investigated the methods of computing right contexts, recently, we find that most of right contexts are not dependent on left contexts. In other words, right contexts can be pre-computed at compile-time not at run-time, and it enable us to get more run-time efficiency. We showed that most of right contexts are not dependent on left contexts through the experiment on several programming languages.

병렬 반복 셀루라 어레이 구조의 제산기

김우완,정민수 慶南大學校 附設 工業技術硏究所 1997 硏究論文集 Vol.14 No.2

CPU내의 ALU에서 Convergence Division의 Algorithm을 채택하면 승산기 하나로 제산의 기능까지 겸할 수가 있어서, Hardware의 점유 면적 면에서 매우 큰 절약을 할 수 있다. 이때 제산의 속도는 사용되는 승산기의 속도에 전적으로 의존되므로 빠른 승산기의 채택이 관건이다. 따라서 승산을 병렬 처리 할 수 있는Overlapped Multi-bit Scanning의 기법을 이용한 Iterative Cellular Array Multiplier를 이 제산기에 채택하여 그 연산 속도를 고속으로 실행하게 하였다. 이 논문에서는 Convergence Division의 Algorithm과 그 실례를 구체적으로 구현하였으며, Overlapped Four-bit Scanning Iterative Cellular array Multiplier를 Convergence Divider에 채택하였을 경우의 시스템을 구성하였다. When the Convergence Division algorithm is adapted for the ALU in any CPU, the occupied area by the hardware can be remarkably saved because the existing multiplier also performs the dividing function. In this case, the speed of performing the division is fully dependent on the adapted multiplier, hence it is very important to choose the fast multiplier. Therefore, in order to get speed up, the Overlapped Multi-Bit Scanning Iterative Cellular Array Multiplier, which performs the multiplication in parallel, is adapted for the divider here. In this paper, the algorithm of Convergence Division and the practical example are performed in detail. In addition, the system structure, which adapts the Overlapped Four-Bit Scanning Iterative Cellular Array Multiplier for the Convergence Divider, is also shown in detail.

리튬 이온 이차전지를 위한 부극용 Si 특성에 관한 연구

김성호,이상헌,박일현,김민철,우태욱,손영국 부산대학교 생산기술연구소 2000 生産技術硏究所論文集 Vol.59 No.-

리튬이온이차전지의 부극으로 Si를 사용하였다. 부극용 Si전극을 1회 충방전 시 Li이온이 탈 삽입될 때 각각의 전압에서 XRD 회절분석을 통하여 Li이온이 이동하여 Si와 반응하는 것을 조사하였다. 순환전압전류 및 충방전 시험을 통하여 전기 화학적 특성을 측정해본 결과 부극으로써 Si의 산화환원 반응이 양호하게 이루어졌으며 충방전에 대한 cycle number가 증가할수록 비가역적인 산화환원반응 및 부피변화로 인해 싸이클 특성 감소함을 나타내었다. Si with anode is used Li ion secondary batteries During Li ion intercalating at first cycle, XRD analysis studies at others voltages showed that Li ions are moved and reacted to Si The electrochemical properties of Si anode materials were evaluated by cyclic voltammetry and charge/discharge test. With cycle number increasing, cyclic characteristics are decreased for irreversible reduction/oxidation and volume change.

사과 열과(裂果)의 원인과 그 방지에 관한 연구

권병규,강영호,이우승,성민웅,한강원 경북대학교 1971 生産技術 Vol.5 No.-

On the basis of our hypothesis about the causes of cracking has obtained in our 1969's study, we investigated the relations among the cracking and the microelements, the environmental factors, and the treatment of IAA and GA in two selected orchards. We analyzed and compared with the contents of microelements (Mn, B, zn, and Cu) in leaves and soils of two test orchards (Taegu and Yungju). The results of the study which the causes of cracking of apples are examined through the above three procedures, are as follows: 1. The contents of Mn in soil of Taegu test orchard were total Mn 435.9 ppm, soil sol'n Mn 6.2ppm, and total Mn 284.6 pm in leaves. That of Yungju test orchard were total Mn 595.1ppm, soil sol'n Mn 6.2ppm and total Mn 144.2ppm in leaves. Comparing with Mn optimum contents in leaves Mn contents of Taegu test orchard were higher than the optimum concentration, while those of Yungju were approximately satis-factory. 2. The contents of B in leaves were 3.7ppm in Taegu and 4.6ppm in Yungju. These contents were lower ten times than the optimum contents and were the same deficiency in both test orchards. 3. The contents of Zn in leaves were 5.7ppm in Taegu and 3.8ppm in Yungju. Those contents were both the same deficiency as comparing with the optimum contents. 4. The contents of Cu in leaves were 29.3ppm in Taegu test orchard and 10.6ppm in Yungju test orchard. Comparing with the optimum contents, the contents of Cu were excess in Taegu test orchard, while that of Cu were approximately satisfactory in Yungju 5. The diameter of Ralls apple fruits were increased 1.1% in IAA spraying treatment and 3.1% in GA spraying treatment as comparing with control group 6. The thickness of cuticle layer of Ralls apple fruits were highest and the cuticle treated with IAA and GA was thinner than the control group. 7. New branches of tree with higher cracking rate tended to decrease in length, in figure and size of leaves. 8. The change of diameter in fruits were decreased in higher cracking fruits during day and night. The change of that in IAA and GA group were increased 6.1% and 1.2% respectively compared with the control group. 9. The application of IAA and GA solution slowed the cracking rate by 2.2 and 0.8% respectively compared with the control group 10. In 1970 year the cracking rate of Ralls apple fruit were 6.53% in Taegu and 4.31% in Yungju test orchard. 11. We obtained linear regression of rate of cracking and the summation of temperature during May to August in Taegu area. The summation of temperature was 2428.1℃ during June to August in 1970. When the summation of temperature was increased more than above that of tempera ture, we could expect that it was possible to increase the rate of cracking Ralls apple. An equation in the summation of temperature and the rate of cracking fruits during May to August were obtained y=0.074x-157.50. 12. The investigation indicates that a method of preventing the cracking of Ralls apple is: a. to spray at the optimum time growth hormone which increases the elasticity and elongation of cell wall. b. to alter the composition of soil by putting the organic fertilizer deeply in the ground. c. to replace Ralls apples with new varieties which is strong against cracking and have high quality and economical productivity.

사과의 열과원인에 관한 조사연구

권병규,강영호,이우승,성민웅,이상윤,조화석 慶北大學校 生産技術硏究所 1970 生産技術 Vol.4 No.-

It is very important to eliminate the immense economic loss caused by cracking in apples through examining the causes of cracking and divising a possible method of prevention of it. Several investigators published their findings on the causes of the cracking of apples which develop on the skin of Ralls apples. However, no definite conclusions or established methods of prevention have been published to this date. Therefore, in this study the causes of the cracking of apples are examined through the use of several methods: (a) the histological and physiological, (b) the microelemental, and (c) the natural environmental. The results are as follows: 1). At the early stage of growth, the thicknesses of the cuticle, as well as of the subepidermis, were the same in Ralls apples without envelopes, Ralls with envelopes, and Jonathan. However. at maturity. the thicknesses differed in the following manner; Ralls apples without envelopes were thickest: Ralls envelopes were less thick than those without envelopes; while Jonathan apples were thinest. 2). Although in the Ralls without envelopes the epidermis is arranged in a brick wall like layer during maturity, in the middle of August the brick wall like epidermis begins to collapse and is surrounded by the cuticle. The process of cracking seems to start with the lenticle and the fruit spot. 3). The rate of cracking was slowed by application of a mixture of IAA and Bordeaux mixture solution, but cracking was not completely halted by this treatment. 4). The stem of a branch laden with apples was put into a solution containing Mn-54, and after absorption took place the distribution of Mn-54 was measured. The results of the measurements were as follows; the bark contained the most Mn-54; the leaves contained the second largest quantitiy; and the apples has the least. 5). The two orchards which were tested tended to have a low soil pH, and a high concentration of soil-solution Mn. 6). The soil with a high rate of cracking tended to have a high pH, which the soil with a low rate had a low pH. 7). In trees with a high rate of cracking, the amount of Mn in the leaves was equal to the amount in the stalk. However, in trees with a low rate of cracking, the amount of Mn in the leaves tended to be high compared with that found in the stalk. 8). The epidermis of the Ralls had a high Ca content than the epidermis of the Johnathan. 9). The epidermis of cracked apples tended to have a higher content of Ca, K,P, Cu and Fe than the epidermis of sound apples. 10). Amoug the apples tested, 11% cracked during the course of the year, with the cracking starting in the middle of Sept. 1969, This low percentage of cracking can be attributed to the small amount of rain during harvest time (late Sept. and October). The total of the added temperature during May, June, and July was 1962℃. 11). Cracking occurred more frequently in apples on the periphery of the tree, in well-colored apples, on the south side of the apples, and on the cheeks of the apples. These occurrances can perhaps be attributed to the amount of sunlight. 12). In the trees tested with newspaper envelops, cracking occurred in 1.9% of the apples with envelopes, and in 11.9% of the apples without envelopes. In the trees tested with Polysteron paper envelopes, cracking occurred in 2.5% of the apples with envelops, and 13.4% of the apples without envelopes. The apples with Polysteron paper envelopes were less infected by insects than the apples with newspaper envelopes. 13). Cracking occurred in 2.4% of the apples covered with vinyl, while in trees not covered with vinyl, 16.6% of the apples crack. The Artificial precipitation produced during harvest time increased the rate of cracking.

유기질비료 시비량에 따른 오미자 묘목의 초기 생육특성에 관한 연구

이경아,박태호,박성용,김도현,오문국,김민수,안태진,이상원,김영국,안영섭,박충범,차선우,송범헌 忠北大學校 農業科學硏究所 2015 農業科學硏究 Vol.31 No.1

This study was carried out to have basic and applied informations to find the optimum nitrogen fertilization level for organic cultivation and to investigate early growth characteristics of Schizandra chinensis Baillon. Different application levels of the organic fertilizer were based on the recommended rate of N fertilizer. Five different levels of the organic fertilizer were applied to S. chinensis and early growth responses such as the length of vine, the diameter of vine, the number of leaves, and the number of branches were investigated. Lengths of main and total vines were shown longer at the level of 1.0 time organic fertilizer than those at others. The vine length at early growth was the highest at the level of 1.0 time organic fertilizer among the treatments. Stem diameter was shown thicker level of 1.0 time organic fertilizer than others on August and September, whereas on October it was the thickest in the conventional cultivation. Number of leaf was increased higher at the level of 1.0 and 2.0 times organic fertilizer than that in the compared to conventional. The number of branches was appeared the lowest at the level of 1.0 time organic fertilizer at early growth, however they were increased through progressing their growth stages. They were not significantly difference among the treatments except for the level of 2.0 times organic fertilizer. Based on the research results, the growth of S. chinensis was commonly higher at the level of 1.0 time organic fertilizer compared to other treatments.

소부혈(少府穴) 자침(刺鍼)이 Kainic Acid로 유도(誘導)된 간질(癎疾) 동물(動物)모델의 해마(海馬) 치상회(齒狀回)에 미치는 영향(影響)

김승태 ( Seung Tae Kim ),정주호 ( Joo Ho Chung ),정우병 ( Wu Byung Jeong ),김장현 ( Jang Hyun Kim ),강민정 ( Min Jung Kang ),홍미숙 ( Mee Sook Hong ),박해정 ( Hae Jeong Park ),김연정 ( Yeon Jung Kim ),박히준 ( Hi Joon Park ),이혜 대한경락경혈학회 2007 Korean Journal of Acupuncture Vol.24 No.4

Objectives: Epilepsy is one of the most common serious brain disorders that affect people of all ages, and it is characterized by recurrent unprovoked seizures. We examined whether acupuncture can reduce both the incidence of seizures and hippocampal cell death in dentate gyrus (DG) using a mouse model of kainic acid (KA)-induced epilepsy. Methods: ICR mice (20~25g) were given acupuncture once a day at acupoint HT8 (sobu) bilaterally during 2 days before KA injection. After an intracerebroventricular injection of 0.1μg of KA, acupuncture treatment was subsequently administered once more (total 3 times), and the degree of seizure was observed for 20 min. Three hours after injection, we confirmed the neural cell death using cresyl violet staining and silver impregnation staining, and determined the expressions of c-Fos and glutamate decarboxylase (GAD)-67 using immunohistochemistry techniques in the DG. Results: KA induced epileptic seizure, neural cell death, increased c-Fos expression and decreased GAD-67 expression in the DG. Acupuncture treatment at HT8 reduced the severity of the epileptic seizure and inhibited neural cell death from KA. In addition, acupuncture normalized the expressions of c-Fos and GAD-67 in the same areas. Conclusions: These results demonstrated that acupuncture treatment at HT8 may reduce the KA-induced epileptic seizure and neural cell death in the DG possibly by normalizing c-Fos expressions and the gamma-aminobutyric acid neurons.

Effects of Vitamin D Supplementation on Children with Autism Spectrum Disorder: A Systematic Review and Meta-analysis

Min Zhang(Min Zhang),YiRan Wu(YiRan Wu),ZhaoXu Lu(ZhaoXu Lu),MeiYan Song(MeiYan Song),XiaoLan Huang(XiaoLan Huang),LaLa Mi(LaLa Mi),Jian Yang(Jian Yang),Xiaodai Cui(Xiaodai Cui) 대한정신약물학회 2023 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.21 No.2

The effect of vitamin D supplementation on individuals with autism spectrum disorder (ASD) is inconclusive. We aimed to conduct a meta-analysis of the available randomized controlled trials (RCTs) to explore whether vitamin D supplementation can improve core symptoms and coexisting conditions in children with ASD. Data were obtained by searching the PubMed, Embase, Web of Science, CINAHL and Cochrane Library databases up to February 2022 following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Using a random-effects model, mean differences with 95% confidence intervals (CIs) were calculated through a meta-analysis. There were eight RCTs with 266 children with ASD in the present review, among which six RCTs were included in the meta-analysis. Children who received vitamin D supplementation showed a significant improvement in stereotypical behavior scores (pooled mean difference (MD): −1.39; 95% CI: −2.7, −0.07; p = 0.04) with low heterogeneity (I2 = 34%), and there was a trend toward decreased total scores on the Social Responsiveness Scale (SRS) and Childhood Autism Rating Scale (CARS, p = 0.05); however, there were no other significant differences in the core symptoms of ASD and coexisting conditions between groups as measured by the Aberrant Behavior Checklist (ABC). Vitamin D supplementation appears to improve stereotypical behaviors but does not improve other core symptoms and coexisting conditions. Further randomized controlled trials with large sample sizes and individualized doses are needed.