Highly Porous Cellulose Microbeads and their Adsorption for Methylene Blue

Jiarui Hua,Ranju Meng,Tiejun Wang,Huiying Gao,Zhenze Luo,Yuanyuan Jin,Lin Liu,Juming Yao 한국섬유공학회 2019 Fibers and polymers Vol.20 No.4

Highly porous cellulose microbeads with porosity of more than 90 % were successfully prepared via a faciledissolution and subsequent regeneration of cellulose in H2SO4/Na2SO4 coagulation bath. Effects of coagulation temperature,H2SO4, and Na2SO4 concentration on the microstructure, average diameter, porosity, specific surface area, and mechanicalproperty of formed cellulose beads were investigated systematically. In view of the high porosity and specific area, thecellulose beads were used as adsorbents for dye removal. The results revealed that the porous cellulose beads exhibited highadsorption performance with maximum adsorption capacity of 48.80 mg/g for cationic dye methylene blue. Besides, theporous cellulose beads also presented a potential in practical application and its adsorption capacity for methylene blue stillretained 29.43 mg/g after six adsorption-desorption cycles.

In-situ XPS Study of Core-levels of ZnO Thin Films at the Interface with Graphene/Cu

Jinsung Choi,Ranju Jung 한국물리학회 2018 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.73 No.10

We have investigated core-levels of ZnO thin films at the interface with the graphene on Cu foil using in-situ X-ray Photoelectron Spectroscopy (XPS). Spectral evolution of C 1s, Zn 2p, and O 1s are observed in real time during RF sputtering deposition. We found binding energy (BE) shifts of Zn 2p and `ZnO' state of O 1s depending on ZnO film thickness. Core-levels BE shifts of ZnO will be discussed on the basis of electron transfer at the interface and it may have an important role in the electronic transport property of the ZnO/graphene-based electronic device.

Structural Properties and Resistance-Switching Behavior of Thermally Grown NiO Thin Films

Kim, Dong-Wook,Jung, Ranju,Park, Bae Ho,Li, Xiang-Shu,Park, Chanwoo,Shin, Seongmo,Kim, Dong-Chirl,Lee, Chang Won,Seo, Sunae IOP Publishing 2008 Japanese journal of applied physics Vol.47 No.r3

Soluble and Membranous Vascular Endothelial Growth Factor Receptor-2 in Pregnancies Complicated by Pre-Eclampsia

Richa Tripathi,Gayatri Rath,Ranju Ralhan,Sunita Saxena,Sudha Salhan 연세대학교의과대학 2009 Yonsei medical journal Vol.50 No.5

Purpose: There is a paucity of information on the serum soluble vascular endothelial growth factor receptor-2 (sVEGFR-2) concentrations, membranous VEGFR-2 expression and the mechanism involved in their modulations during the clinical onset of pre-eclampsia. This cross-sectional study was conducted to evaluate the concentration of sVEGFR-2 in serum and to investigate the expression of membranous VEGFR-2 in placentae of pre-eclampsia group. Materials and Methods: The serum levels of sVEGFR-2 (n = 120) and the expression of membranous VEGFR-2 in placentae (n = 100) were analysed at third trimester of pregnancy by enzyme linked immunosorbent assay (ELISA) and immunohistochemistry respectively. The diagnostic parameters of sensitivity, specificity and association of soluble and membranous VEGFR-2 in these patients were evaluated. Results: The serum levels of sVEGFR-2 in pre-eclampsia patients were found to be significantly reduced (p = 0.01, p = 0.001) in early and late pre-eclamptic sub-groups as compared to their respective third trimester control sub-groups. Also, the receiver operating characteristic (ROC) curve analysis showed a cut-off value of 7350.4 pg/mL, higher sensitivity (76%) and specificity (76%) for sVEGFR-2 in late onset (> 34 weeks) pre-eclamptic group. Significant down-regulation of membranous VEGFR-2 immunoreactivity was observed in all the placental cells (p = 0.0001) at > 34 weeks preeclamptic group. Conclusion: The reduced serum levels of soluble VEGFR-2 and the down-regulated expression of membranous VEGFR-2 in the study group denoted abnormality in VEGF mediated placental function in all placental cells and thus VEGFR-2 may be a key factor, intimately associated with pre-eclampsia. This study shows the clinical utility of soluble and membranous VEGFR-2 in pre-eclampsia patients. Purpose: There is a paucity of information on the serum soluble vascular endothelial growth factor receptor-2 (sVEGFR-2) concentrations, membranous VEGFR-2 expression and the mechanism involved in their modulations during the clinical onset of pre-eclampsia. This cross-sectional study was conducted to evaluate the concentration of sVEGFR-2 in serum and to investigate the expression of membranous VEGFR-2 in placentae of pre-eclampsia group. Materials and Methods: The serum levels of sVEGFR-2 (n = 120) and the expression of membranous VEGFR-2 in placentae (n = 100) were analysed at third trimester of pregnancy by enzyme linked immunosorbent assay (ELISA) and immunohistochemistry respectively. The diagnostic parameters of sensitivity, specificity and association of soluble and membranous VEGFR-2 in these patients were evaluated. Results: The serum levels of sVEGFR-2 in pre-eclampsia patients were found to be significantly reduced (p = 0.01, p = 0.001) in early and late pre-eclamptic sub-groups as compared to their respective third trimester control sub-groups. Also, the receiver operating characteristic (ROC) curve analysis showed a cut-off value of 7350.4 pg/mL, higher sensitivity (76%) and specificity (76%) for sVEGFR-2 in late onset (> 34 weeks) pre-eclamptic group. Significant down-regulation of membranous VEGFR-2 immunoreactivity was observed in all the placental cells (p = 0.0001) at > 34 weeks preeclamptic group. Conclusion: The reduced serum levels of soluble VEGFR-2 and the down-regulated expression of membranous VEGFR-2 in the study group denoted abnormality in VEGF mediated placental function in all placental cells and thus VEGFR-2 may be a key factor, intimately associated with pre-eclampsia. This study shows the clinical utility of soluble and membranous VEGFR-2 in pre-eclampsia patients.

Study of electronic structures of ZnO thin film at the interface with 2D materials

Jinsung CHOI,Woochul YANG,Ranju JUNG 한국진공학회 2016 한국진공학회 학술발표회초록집 Vol.2016 No.8

Composition dependence of unipolar resistance switching in TaOx thin films

Kurnia, F.,Hadiyawarman,,Jung, C. U.,Jung, Ranju,Liu, Chunli Wiley (John WileySons) 2011 Physica status solidi. PSS-RRL. Rapid Research Let Vol.5 No.7

Improved Resistance Switching Stability in Fe-Doped ZnO Thin Films Through Pulsed Magnetic Field Annealing

Xu, Hongtao,Wu, Changjin,Xiahou, Zhao,Jung, Ranju,Li, Ying,Liu, Chunli Springer US 2017 Nanoscale research letters Vol.12 No.1

<P>Five percent of Fe-doped ZnO (ZnO:Fe) thin films were deposited on Pt/TiO<SUB>2</SUB>/SiO<SUB>2</SUB>/Si substrates by a spin-coating method. The films were annealed without (ZnO:Fe-0T) and with a pulsed magnetic field of 4 T (ZnO:Fe-4TP) to investigate the magnetic annealing effect on the resistance switching (RS) behavior of the Pt/ZnO:Fe/Pt structures. Compared with the ZnO:Fe-0T film, the ZnO:Fe-4TP film showed improved RS performance regarding the stability of the set voltage and the resistance of the high resistance state. Transmission electron microscopy and X-ray photoelectron spectroscopy analyses revealed that the ZnO:Fe-4TP film contains more uniform grains and a higher density of oxygen vacancies, which promote the easier formation of conducting filaments along similar paths and the stability of switching parameters. These results suggest that external magnetic fields can be used to prepare magnetic oxide thin films with improved resistance switching performance for memory device applications.</P>

운송물류 부문 발생의 탄소배출권 거래제도에 관한 비교연구

박명섭(PAK MYONG SOP),홍란주(Ranju Hong) 법무부 국제법무정책과 2011 통상법률 Vol.- No.97

Transport logistics sector has long been developed with the growth of global economy. Transport sector CO2 emissions represent 23% globally of overall CO2 emissions from Fossil fuel combustion. The sector accounts for approximately 15% of overall greenhouse gas emissions. The Global CO2 emissions from transport have grown by 45% from 1990 to 2007, led by emissions from the road sector in terms of volume and by shipping and aviation in terms of highest growth rates. To reduce and control the excessive emissions in transport sector, developed countries are using the Kyoto Flexibility Mechanisms, expecially Emissions Trading(ET). Currently the ET includes road transport sector in the Annex-I countries of the Kyoto Protocol. The EU, which ranked 3rd on global CO2 emissions in 2009, has EU-ETS on road transport sector and plans to extend it from 2011 to include the aviation. The US, which ranked 2nd, operates the regional greenhouse gas initiative, yet it doesn't include transport sector. Several regulations on vehicle emissions in the US, mostly regard to alternative fuel vehicles and electricity based vehicles. In Japan, which ranked 6th, four trading schemes are running, and the JVETS and the Domestic Credit Schemes dealing with road transport sector. The allowances traded in the EU and Japan are based on the cap and trade systems, however, the EU forces the rules and Japan takes voluntary participation. Hence, the main purpose of this study is to reviews on emissions trading schemes and the regulations regarding transport logistics sector especially in the EU, the US, and Japan, and to describe some implications. To meet this purpose, this paper provides an overview of the current international legal framework and the relevant mechanisms to keep emissions from transport logistics sector. This paper not only analyzes each countries individual ETS and regulations for the reduction, but it also presents some implications on the reduction of transport logistics sector to the Republic of Korea, which has the possibility to become the one of Annex-I countries after 2013.

Resistance switching characteristics in Li-doped NiO

Jung, Kyooho,Choi, Joonhyuk,Kim, Yongmin,Im, Hyunsik,Seo, Sunae,Jung, Ranju,Kim, DongChul,Kim, J.-S.,Park, B. H.,Hong, J. P. American Institute of Physics 2008 JOURNAL OF APPLIED PHYSICS - Vol.103 No.3

Secondary Electron Emission of ZnO Films

Choi, Jinsung,Lee, Sung Kwang,Choi, Joon Ho,Choi, Eun Ha,Jung, Ranju,Kim, Yunki The Korean Vacuum Society 2015 Applied Science and Convergence Technology Vol.24 No.6

We investigated secondary electron emission characteristics of ZnO thin films prepared by pulsed laser deposition method with respect to the ambient oxygen pressure and the substrate temperature during the deposition. X-ray diffraction, UV-Vis spectrometry, atomic force microscopy, and ${\gamma}$-FIB were used to examine the structural, optical transmission, surface morphology, and secondary electron emission properties of the films, respectively. The secondary electron emission coefficient of the ZnO films increases as the O/Zn ratio of the films increases which was thought to result from either the ambient oxygen pressure increase or the substrate temperature decrease and as the grain size of the films decreases. It was confirmed that ZnO has better secondary electron emission characteristics than those of MgO, which is currently widely used as a material for PDP protecting layers.