Kinetic Study on Aminolysis of 4-Chloro-2-Nitrophenyl X-Substituted-Benzoates in Acetonitrile and in 80 mol % H2O/20 mol % DMSO: Effect of Medium on Reactivity and Reaction Mechanism

Ha-Ram Kim,Tae-Il Um,Min-Young Kim,엄익환 대한화학회 2014 Bulletin of the Korean Chemical Society Vol.35 No.4

A kinetic study on aminolysis of 4-chloro-2-nitrophenyl X-substituted-benzoates (6a-i) in MeCN is reported. The Hammett plot for the reactions of 6a-i with piperidine consists of two intersecting straight lines, while the Yukawa-Tsuno plot exhibits an excellent linear correlation with ρX = 1.03 and r = 0.78. The nonlinear Hammett plot is not due to a change in rate-determining step (RDS) but is caused by the resonance stabilization of substrates possessing an electron-donating group in the benzoyl moiety. The Brønsted-type plot for the reactions of 4-chloro-2-nitrophenyl benzoate (6e) with a series of cyclic secondary amines is linear with βnuc = 0.69, an upper limit for reactions reported to proceed through a concerted mechanism. The aminolysis of 6e in aqueous medium has previously been reported to proceed through a stepwise mechanism with a change in RDS on the basis of a curved Brønsted-type plot. It has been concluded that instability of the zwitterionic tetrahedral intermediate (T±) in MeCN forces the reaction to proceed through a concerted mechanism. This is further supported by the kinetic result that the amines used in this study are less reactive in MeCN than in H2O, although they are more basic in MeCN over 7 pKa units.

Effects of 1-methyl cyclopropane (1-MCP) Treatment on Fruit Quality Attributes in ‘Green Ball’ and ‘Honggeum’ Apples during Cold Storage

Ha-Ram Jung,Jingi Yoo,Nay Myo Win,Jung-Geun Kwon,Seon-Hyang Kim,Hye-Won Kwon,Hye-Jin Cho,Dea Hyun Kim,Ye-Eun Kim,Hyun-Nam Kim,Young-Je Cho,In-Kyu Kang 한국원예학회 2019 한국원예학회 학술발표요지 Vol.2019 No.10

Electrocardiogram abnormalities in antimony exposed workers in the automotive brake lining manufacturing industry: a case report

Ha-ram Jo,Seongyong Yoon,Jinseok Kim,Seong-yong Cho,Jong-min An,Gayoung Kim 대한직업환경의학회 2022 대한직업환경의학회지 Vol.34 No.-

Analysis of Factors Influencing Food Purchasing Behavior of Consumers In Mobile Shopping Malls

Ha Ram Eom,Jung Hoon Moon,Jong Tae Lee 한국콘텐츠학회 2016 International Journal of Contents Vol.12 No.4

This study focuses on finding ways to stimulate the growth of agricultural sectors in m-businesses, by analyzing and comparing the factors that influence the purchasing behavior of consumers in the open market, social commerce, and integrated shopping malls. Consumers at various mobile shopping malls answered a survey. Among the nine factors considered, one important factor was the frequency of purchasing agrifoods. Regression analysis produced three results. First, in the open market, in addition to various other advantages, the brand image, reasonable pricing, simple payment system, and convenience of using an app were important factors that influenced the purchasing behavior of the individual consumer. Second, in social commerce, the major factors influencing purchase were the reasonable pricing, quick delivery service, and convenience of using an app. Third, in integrated shopping malls, the brand image, guaranteed after-sale service, the variety of products, quick delivery service, and convenience of using an app were the significant factors.

Phenolic Profiles of Hardy Kiwifruits and Their Neuroprotective Effects on PC-12 and SH-SY5Y Cells against Oxidative Stress

( Ha-ram Jeong ),( Kwan Joong Kim ),( Sang Gil Lee ),( Hye Sung Cho ),( Youn-sup Cho ),( Dae-ok Kim ) 한국미생물 · 생명공학회 2020 Journal of microbiology and biotechnology Vol.30 No.6

Hardy kiwifruits (Actinidia arguta Planch.) have high amounts of antioxidants, including ascorbic acid (vitamin C) and phenolics. The anti-cholinesterase activity and neuroprotective effects of three different cultivars of hardy kiwifruits, cv. Mansu (A. arguta × A. deliciosa), cv. Haeyeon (A. arguta), and cv. Chiak (A. arguta), on PC-12 and SH-SY5Y cells were evaluated. Extraction of phenolics and vitamin C was carried out using 80% (v/v) aqueous ethanol and metaphosphoric acid assisted with homogenization, respectively. Hardy kiwifruit of cv. Mansu showed higher total phenolic, total flavonoid, and vitamin C contents and antioxidant capacity compared to the other two cultivars of hardy kiwifruits, cv. Haeyeon and cv. Chiak. Analysis of high-performance liquid chromatography results revealed the presence of procyanidin B2, (-)-epicatechin, neochlorogenic acid, cryptochlorogenic acid, rutin, hyperoside, isoquercitrin, and astragalin in hardy kiwifruits. The three cultivars of hardy kiwifruits had a wide range of vitamin C content of 55.2-130.0 mg/100 g fresh weight. All three cultivars of hardy kiwifruits had protective effects on neuronal PC-12 and SHSY5Y cells exposed to hydrogen peroxide by increasing cell viability and reducing intracellular oxidative stress. Furthermore, the hardy kiwifruits inhibited acetylcholinesterase and butyrylcholinesterase. Collectively, these results suggest that hardy kiwifruits rich in antioxidants like phenolics and vitamin C have good potential as functional materials in neuroprotective applications.

실내 저광 조건에서 한국 특산 좀비비추의 생장 반응

Ha Ram Yang,Yeon Ju Park,Min Ji Kim,연제연,김완순 한국원예학회 2022 원예과학기술지 Vol.40 No.3

To check the availability of indoor plants, we investigated the growth and photo-physiological responses in Korean endemic Hosta minor for three months of artificial low light conditions (10, 30, and 50 μmol·m-2·s-1, abbreviated as L10, L30, and L50). In the L10 treatment, the growth indicators leaf number and size, shoot biomass, and tillering capacity declined by 20–50% decline from the initial values, and those were maintained or slightly increased in the L30 treatment and significantly increased to 200–300% in the L50 treatment. The light use efficiency values supported this result, which were –0.12, 0.04, and 0.16 in L10, L30, and L50, respectively. Growth adaptation to the indoor artificial lighting took four to six weeks. Net photosynthesis also decreased from the initial value after four weeks but increased in the ninth week, showing significant differences among the different light intensity levels. The light compensation point was 17 ± 6.16 μmol·m-2·s-1, and the light saturation point ranged from 200 to 350 μmol·m-2·s-1. Regardless of the light intensity, the Fv/Fm values were 0.79 to 0.83, indicating a normal level, and the OJIP curve also showed no significant difference. These results indicate that the low light intensity of 10 μmol·m-2·s-1 did not damage photosystem II but gradually negatively affected the growth of Hosta minor. We concluded that the minimum light intensity is 10 to 30 μmol·m-2·s-1 in Hosta minor and requires four weeks of low light adaptation. 한국 특산식물 좀비비추(Hosta minor)의 실내 이용을 위해 저광 조건(10, 30, 50µmol·m-2·s-1; L10, L30, L50)에서 3개월 간 생장 반응과 광 생리 특성을 조사하였다. 잎과 지상부, 분얼 생장 모두 초기생장(0주차)과 비교하여 L10에서는 증가 없이 오 히려 감소하였고(20–50%), L30에서는 유지되거나 약간 증가하였으며(10–50%), L50에서는 200–300% 수준으로 현저 하게 늘어났다. 처리기간 동안 건물 증가율은 L10, L30, L50에서 –20%, 10%, 90%, 광이용효율 역시 –0.12, 0.04, 0.16으로 나타났다. 순광합성량은 4주차 때는 초기값(0주차)보다 오히려 감소하였으나, 9주차 이후 증가하며 처리간 유의한 차이를 보 였다. 평균 광보상점은 17 ± 6.16µmol·m-2·s-1, 광포화점은 200–350µmol·m-2·s-1로 측정되었다. 광도와 관계없이 모든 처리 구 Fv/Fm 값은 0.79–0.83으로 정상 수준을 나타냈고, OJIP 곡선 역시 큰 차이를 보이지 않았다. 이상에서 10µmol·m-2·s-1 저 광도 조건은 광계Ⅱ 손상을 가져오지는 않았으나, 생장을 억제시키는 비생물적 스트레스 요인으로 작동하였다. 결론적으로 좀 비비추의 실내 이용을 위해서는 4주간의 적응이 필요하며, 한계 광도는 10–30µmol·m-2·s-1로 판단된다.

Thermodynamical and Rheological Properties of Wheat Flour Dough Depending on Salt Level

Ha Ram Kim,A-Reum Ryu,Ji-Eun Bae,Ah Leum Kim,Jung Sun Hong,Hee-Don Choi 한국식품영양과학회 2022 한국식품영양과학회 학술대회발표집 Vol.2022 No.10

아이돌보미의 안전행동 실천에 영향을 미치는 요인: 안전지식, 안전인식, 안전효능감을 중심으로

문하람(Ha-Ram Moon),어용숙(Yong-Sook Eo) 한국산학기술학회 2020 한국산학기술학회논문지 Vol.21 No.12

본 연구는 아이돌보미의 안전지식, 안전인식, 안전효능감과 안전행동실천과의 관계를 파악하기 위하여 실시한 서술적 조사연구이다. 자료수집은 2019년 12월부터 2020년 1월까지 경상북도 소재 2개 시에서 아이돌보미 양성교육과정을 이수하여 아이돌보미 자격을 갖춘 아이돌보미 199명을 대상으로 시행되었다. 자가 보고식 설문지를 사용하였으며, 수집된 자료는 SPSSWIN 25.0 Program을 이용하여 기술통계(빈도, 백분율, 평균, 표준편차)를 실시하고, t-test, ANOVA, Pearson’s correlation coefficient, multiple regression으로 분석하였다. 연구결과 아이돌보미의 안전지식은 0.64(±0.09)점이었으며, 안전인식은 1.92(±0.37)점, 안전효능감은 4.18(±0.51)점, 안전행동실천은 2.55(±0.36)점이었다. 안전행동 실천은 안전지식(r=.14, p =.042), 안전효능감(r=.43, p <.001)과 안전효능감의 하위요인인 자기조절(r=.32, p <.001), 주위사람 도움(r=.40, p <.001), 주위환경 조절(r=.39, p <.001)과 유의한 정적 상관관계를 보였다. 아이돌보미의 안전행동실천 영향요인으로 안전효능감의 하부요인인 주위사람 도움(β=.24, p =.009)과 주위환경 조절(β=.19, p =.039)이었으며, 이들 요인들의 안전행동 실천 설명력은 20.0%이었다. 이와 같은 결과에 따라 아이돌보미의 안전행동실천을 높이기 위해서는 안전효능감을 증진시키는 방안을 마련할 필요가 있다. This study examined the correlation between safety practices and safety knowledge, safety awareness and safety efficacy, and the factors influencing the safety practices of in-home child-care providers. The participants were 199 in-home child-care providers who worked at two cities in G province. Using a structured-questionnaire, the data were collected from December 2019 to January 2020. The data were analyzed using the IMB/SPSS 25.0 program. The collected data were analyzed using descriptive statistics (frequency, percent, mean, and SD), a t-test, ANOVA, Scheff test, Pearson Correlation Coefficient, and multiple regression. The mean score for safety knowledge, safety awareness, safety efficacy, and safety practices were 0.64 (SD, 0.09), 1.92 (SD, 0.37), 4.18 (SD, 0.51), and 2.55 (SD, 0.36), respectively. Safety practices were positively correlated with the safety knowledge (r=.14, p=.042), safety efficacy (r=.43, p<.001), and sub-factors of safety efficacy, self-regulation (r=.32, p<.001), enlisting social support (r=.40, p<.001), and controlling the environment (r=.39, p<.001). Enlisting social support and controlling the environment, sub-factors of safety efficacy were influenced safety practices significantly and explained 20.0% of the variance. Based on these findings, it will be necessary to develop a program that can enhance their safety efficacy for safety practices of in-home child-care providers.

초등학생의 식습관 개선을 위한 도시농업 프로그램의 효과

김하람(Ha Ram Kim),김선옥(Seon Ok Kim),박신애(Sin Aae Park) 한국원예학회 2019 한국원예학회 학술발표요지 Vol.2019 No.10

Kinetic studies of <i>in vitro</i> digestion of amylosucrase-modified waxy corn starches based on branch chain length distributions

Kim, Ha Ram,Choi, Seung Jun,Park, Cheon-Seok,Moon, Tae Wha Elsevier 2017 Food hydrocolloids Vol.65 No.-

<P><B>Abstract</B></P> <P>Classification of starch into rapidly digestible starch (RDS), slowly digestible starch (SDS), and resistant starch (RS) has been in controversy. Therefore, this study aimed to ascertain the individual existence of RDS and SDS using amylosucrase-modified starch. Enzymatic hydrolysis curves of modified waxy corn starches were obtained and fitted to a logarithm of slope (LOS) plot. LOS plots for amylosucrase-modified starches revealed a discontinuity, reflecting the change of rate constant <I>k</I> during digestion, such that distinguishable <I>k</I> s for each of the phases were defined (<I>k</I> <SUB> <I>RDS</I> </SUB>, <I>k</I> <SUB> <I>SDS</I> </SUB>). The LOS plot approach could be utilized as a persuasive basis for the classification of the starch fractions. The structure of amylosucrase-modified starches was characterized before and after removal of RDS and/or SDS. Branch chains with certain lengths contributed to the organization of each fraction and determined the primary crystallite configuration of amylosucrase-modified starches causing the diversity of digestion properties.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Enzymatic hydrolysis curves of starches were fitted to a logarithm of slope plot. </LI> <LI> The change in rate constant during digestion was observed. </LI> <LI> The individual existence of RDS and SDS was proven in amylosucrase-modified starch. </LI> <LI> The structure of starches was investigated before and after digestion. </LI> <LI> Amylopectin chain length determined the arrangement of each starch fraction. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>