Educational Differentials in the Risk of Divorce and Their Trends across Marriage Cohorts of Korean Women

Hyunjoon Park,James Raymo,Mathew Creighton 한국여성정책연구원(구 한국여성개발원) 2009 Gender Studies and Policy Review Vol.2 No.-

Little research in Korea has systematically examined trends in the risk of marital dissolution, especially trends in educational differentials in divorce. Using individual-level data from the Korean Longitudinal Survey of Women and Family (KLoWF), we investigate how the association between education and divorce has changed across three marriage cohorts of women who married in the 1970s, 1980s, and 1990s, after taking into account various individual controls. The result from the Cox proportional hazard models of the divorce risk shows that the association between educational attainment and divorce has become more negative for younger marriage cohorts. In other words, divorce is increasingly concentrated among women with lower educational attainment than among their counterpart with higher education. We discuss implications of the growing concentration of divorce among low-educated women for socioeconomic differentials in children’s education and well-being.

In Situ Monitoring of Individual Plasmonic Nanoparticles Resolves Multistep Nanoscale Sulfidation Reactions Hidden by Ensemble Average

Park, Youngchan,Oh, Hyuncheol,Park, Jiseong,Choi, Woong,Ryu, Hyein,Seo, Daeha,Song, Hyunjoon American Chemical Society 2019 JOURNAL OF PHYSICAL CHEMISTRY C - Vol.123 No.37

<P>The generation of complex nanostructures to obtain novel characteristics and improved performance has been achieved by coupling multiple nanoscale reactions. Because reactions at the nanometer scale directly govern the morphology of nanostructures, understanding the reaction mechanism is critical to precisely control the morphology and, eventually, the physicochemical properties of the materials. However, because of the ensemble-average effect, investigating the reaction mechanism at the bulk level does not provide sufficient information. In this study, we investigated the overall sulfidation reaction mechanism that occurred on individual silver nanocubes in real time at high temperature. Using the single-particle dark-field imaging technique, three discrete steps of the sulfidation reaction were clearly resolved in the profiles of the plasmon peak shift and the intensity change of individual particles according to time progress: (I) reactant diffusion to the silver surface by passing through a ligand barrier, (II) silver sulfide formation by C-S bond cleavage of cysteine molecules, and (III) diffusion of silver atoms in the silver sulfide layer until the complete formation of silver sulfide. By a combination of simulation and control experiments, physical constants were derived for each step, which is completely hidden in the ensemble measurements. Each individual nanoparticle exhibited a large variation of physical values, such as the reaction rate constant and diffusivity, mainly resulting from the intrinsic structural heterogeneity. Dark-field microscopy image processing based on surface plasmon scattering would be helpful to analyze the reaction kinetics and understand the reaction mechanisms of the numerous multistep nanoscale reactions in real time with high spatial and temporal resolutions under actual reaction conditions.</P> [FIG OMISSION]</BR>

Evaluation of functional properties of lactobacilli isolated from Korean white kimchi

Park, Soyoung,Ji, Yosep,Park, Hyunjoon,Lee, Kyuyeon,Park, Haryung,Beck, Bo Ram,Shin, Heuynkil,Holzapfel, Wilhelm H. Elsevier 2016 Food control Vol.69 No.-

<P>Kimchi, probably Korea's most famous traditional fermented food, is well known for its beneficial properties. Among several hundred different types of kimchi in Korea, white (baek) kimchi is prepared without chilli and is widely appreciated also by non-Koreans because of its unique mild flavour. In an approach to identify the bacteriological basis for proposed health benefits, we isolated 11 Lactobacillus strains from six samples of white kimchi, and investigated their safety and functional features. These strains represented the species Lactobacillus brevis, Lactobacillus plantarum and Lactobacillus sakei that dominated the populations within a range of 3 x 10(6) to 4 x 10(8) CFU/mL. Following safety assessment based on antibiotic resistance and biogenic amine production, 7 different strains were selected for further studies including evaluation of their adaptation to cabbage juice and resistance to phenol. Growth in and adaptation to the cabbage juice was favourably influenced by addition of 2% salt. Final selection was based on in vitro passage of simulated stomach duodenum conditions (SSDP model). The strains L. plantarum HAC01 and L sakei HAC10 were administered to a diet-induced obese (DIO) mouse model receiving a high-fat (HF) diet to assess their functionality in-vivo. Animal groups receiving the viable strains showed significantly lower body weight and total weight gain during 8 weeks compared to the high-fat control group. This study provides preliminary information on the use of in-vitro and in-vivo features for safety and functionality evaluation of Lactobacillus strains from white kimchi. These 'first level' criteria for strain selection may serve as model, thereby facilitating potentially new probiotic developments. (C) 2016 Elsevier Ltd. All rights reserved.</P>

Role of Non-Parquet Diagrams in the Parquet Graph Resummation Method for Two-Dimensional Vortex Liquids

Hyunjoon Park,여준현 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.4

We study the role of the non-parquet diagrams in a nonperturbative approach called the parquet graph resummation method for studying correlations in a two-dimensional vortex liquid. As an analytic approach, the parquet graph resummation method captures the growing crystalline order in the vortex liquid as the temperature decreases. For its systematic improvement, it is important to understand the effects of the non-parquet diagrams, which are neglected in a usual approximation. The contribution of the non-parquet diagrams can be summarized into the non-parquet vertex function that appears in the lowest Landau level formalism of the Ginzburg-Landau theory of a superconductor in a magnetic field. We find that, as the temperature decreases, the non-parquet vertex develops minima at positions of the reciprocal lattice vectors of a triangular lattice where peaks grow in the structure factor of a vortex liquid. By solving the parquet equations for various forms of the non-parquet vertex, we analyze the effects of the minima in the non-parquet vertex on the positions and the sizes of the peaks in the structure factor. We study the role of the non-parquet diagrams in a nonperturbative approach called the parquet graph resummation method for studying correlations in a two-dimensional vortex liquid. As an analytic approach, the parquet graph resummation method captures the growing crystalline order in the vortex liquid as the temperature decreases. For its systematic improvement, it is important to understand the effects of the non-parquet diagrams, which are neglected in a usual approximation. The contribution of the non-parquet diagrams can be summarized into the non-parquet vertex function that appears in the lowest Landau level formalism of the Ginzburg-Landau theory of a superconductor in a magnetic field. We find that, as the temperature decreases, the non-parquet vertex develops minima at positions of the reciprocal lattice vectors of a triangular lattice where peaks grow in the structure factor of a vortex liquid. By solving the parquet equations for various forms of the non-parquet vertex, we analyze the effects of the minima in the non-parquet vertex on the positions and the sizes of the peaks in the structure factor.

Living Arrangements of Single Parents and Their Children in South Korea

Park, Hyunjoon,Choi, Jaesung,Jo, Hyejeong 한국사회학회 2014 한국사회학회 사회학대회 논문집 Vol.2014 No.12

Extremely Active Pd@pSiO₂ Yolk–Shell Nanocatalysts for Suzuki Coupling Reactions of Aryl Halides

Park, Ji Chan,Heo, Eunjung,Kim, Aram,Kim, Mijong,Park, Kang Hyun,Song, Hyunjoon American Chemical Society 2011 The Journal of Physical Chemistry Part C Vol. No.

<P>In the present study, we optimize the yolk–shell nanostructure in a palladium–silica system for the purpose of attaining high activity in Suzuki cross-coupling reactions. Pd@porous SiO<SUB>2</SUB> (Pd@pSiO<SUB>2</SUB>) yolk–shell nanoparticles, bearing tiny palladium cores and highly porous silica hollow shells, were synthesized by direct silica coating and partial etching of the silica layers. High temperature treatment removed all surfactants around the catalyst surface and generated large pores on the silica shells. The resulting Pd@pSiO<SUB>2</SUB> yolk–shell catalysts exhibited extremely high initial turnover frequency of 78000 h<SUP>–1</SUP>, as well as excellent reusability of more than 10 times in a standard Suzuki coupling reaction. The catalysts also catalyzed Suzuki reactions with various substrates including bromo- and chlorobenzene very well.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2011/jpccck.2011.115.issue-32/jp2021825/production/images/medium/jp-2011-021825_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jp2021825'>ACS Electronic Supporting Info</A></P>

When Education Is a Positional Good

Hyunjoon Park,Soo-yong Byun 한국사회학회 2015 한국사회학회 사회학대회 논문집 Vol.2015 No.12

Living Arrangements of Single Parents and Their Children in South Korea

Park, Hyunjoon,Choi, Jaesung,Jo, Hyejeong Haworth Press 2016 Marriage & family review Vol.52 No.1

Changing Relationships between Education and Marriage among Korean Women

Hyunjoon Park,Jae Kyung Lee,Inkyung Jo 한국사회학회 2013 韓國社會學 Vol.47 No.3

Using the data from the 1-percent microdata sample of 2010 Census (N = 107,741), we examine changing relationships between education and first marriage across Korean women of three birth cohorts born in 1951-60, 1961-70, and 1971-80. We apply discrete-time hazard models to the person-year data, allowing the effect of women’s educational attainment on the risk of marriage to fully vary across cohorts and over duration. Women of younger cohorts have increasingly delayed and forgone marriage regardless of educational levels. However, the trend toward later and less marriage has been particularly significant among the lowest educated. In the result, for the youngest cohort, the percentage of women who remained single by the age 39 is highest at both ends of educational attainment. This contrasts the pattern among the oldest cohort where there was a linearly negative relationship between education and marriage, consistent with the findings in other East Asian countries.

ZnO–CuO core–branch nanocatalysts for ultrasound-assisted azide–alkyne cycloaddition reactions

Park, Ji Chan,Kim, A Young,Kim, Jae Young,Park, Sungkyun,Park, Kang Hyun,Song, Hyunjoon unknown 2012 Chemical communications Vol. No.

<P>ZnO–CuO core–branch hybrid nanoparticles, synthesized by copper oxide growth and controlled oxidation on ZnO nanospheres, exhibited remarkable enhancement of catalytic activity and stability for ultrasound-assisted [3+2] azide–alkyne cycloaddition reactions, due to their high surface area and active facets of the CuO branches.</P> <P>Graphic Abstract</P><P>ZnO–CuO core–branch hybrid nanoparticles were synthesized by copper oxide growth and controlled oxidation on ZnO nanospheres, and employed as a highly active heterogeneous catalyst for ultrasound-assisted cycloaddition reactions. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2cc31654d'> </P>