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Synthesis of Zinc Oxide Nanoparticle-(C60) Fullerene Nanowhisker Composite for Catalytic Degradation of Methyl Orange under Ultraviolet and Ultrasonic Irradiation

  • Ko, Jeong Won;Son, Yeon-A;Ko, Weon Bae
    • Elastomers and Composites
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    • v.55 no.4
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    • pp.321-328
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    • 2020
  • Zinc nitrate hexahydrate (Zn(NO3)2·6H2O) and sodium hydroxide (NaOH) were dissolved in distilled water and stirred for 30 min. The resulting solution was sonicated by an ultrasonic wave for 45 min. This solution was washed with distilled water and ethanol after centrifugation; next, it was placed in an electric furnace at 200℃ for 1 h under the flow of Ar gas to obtain zinc oxide nanoparticle. A zinc oxide nanoparticle-(C60) fullerene nanowhisker composite was synthesized using the zinc oxide nanoparticle solution, C60-saturated toluene, and isopropyl alcohol via the liquid-liquid interfacial precipitation method. The zinc oxide nanoparticle and zinc oxide nanoparticle-(C60) fullerene nanowhisker composite were characterized using X-ray diffraction, scanning electron microscopy, and Raman spectroscopy, and they were used for the catalytic degradation of methyl orange (MO) under ultraviolet (at 254 and 365 nm) and ultrasonic irradiation. In addition, the catalytic degradation of MO over the zinc oxide nanoparticle and zinc oxide nanoparticle-(C60) fullerene nanowhisker composite was evaluated using ultraviolet-visible spectroscopy.

Exceptional removal capacity of clenbuterol from aqueous solution by mechano-synthesized [Cu (INA)2]-MOF via ball-mill

  • Marinah Mohd, Ariffin;Usman, Armaya'u;Saw Hong, Loh;Wan Mohd Afiq Wan Mohd, Khalik;Hanis Mohd, Yusoff
    • Membrane and Water Treatment
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    • v.13 no.6
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    • pp.321-335
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    • 2022
  • Copper-based Metal-organic framework (MOF) namely ([Cu (INA)2]-MOF) is synthesized by ball milling and characterized using scanning electron microscopy (SEM) for the topography, microstructure, and elemental evidence determination, powdered X-ray diffraction (XRD) for the crystallinity measurement, thermogravimetric (TG) analysis was performed to determine the thermal stability of the material, and Fourier transformed infrared (FTIR) spectroscopy for functional groups identification. The use of [Cu (INA)2]-MOF as hazardous removal material of β-agonists as persistent hazardous micro-pollutants in our environmental water is first reported in this study. The removal efficiency of the Cu-MOF is successfully determined to be 97.7% within 40 minutes, and the MOF has established an exceptional removal capacity of 835 mg L-1 with 95 % percent removal on Clenbuterol (CLB) even after the 5th consecutive cycle. The Langmuir model of the adsorption isotherms was shown to be more favourable, while the pseudo-second-order model was found to be favoured in the kinetics. The reaction was exothermic and spontaneous from a thermodynamic standpoint, and the higher temperatures were unfavourable for the adsorption study of the CLB. As a result, the studied MOF have shown promising properties as possible adsorbents for the removal of CLB in wastewater.

Prognosis of aerodynamic coefficients of butterfly plan shaped tall building by surrogate modelling

  • Sanyal, Prasenjit;Banerjee, Sayantan;Dalui, Sujit Kumar
    • Wind and Structures
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    • v.34 no.4
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    • pp.321-334
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    • 2022
  • Irregularity in plan shape is very common for any type of building as it enhances better air ventilation for the inhabitants. Systematic opening at the middle of the facades makes the appearance of the building plan as a butterfly one. The primary focus of this study is to forecast the force, moment and torsional coefficient of a butterfly plan shaped tall building. Initially, Computational Fluid Dynamics (CFD) study is done on the building model based on Reynolds averaged Navier Stokes (RANS) k-epsilon turbulence model. Fifty random cases of irregularity and angle of attack (AOA) are selected, and the results from these cases are utilised for developing the surrogate models. Parametric equations are predicted for all these aerodynamic coefficients, and the training of these outcomes are also done for developing Artificial Neural Networks (ANN). After achieving the target acceptance criteria, the observed results are compared with the primary CFD data. Both parametric equations and ANN matched very well with the obtained data. The results are further utilised for discussing the effects of irregularity on the most critical wind condition.

Immediate Effect of the Proprioceptive Spiral Taping Method on Changes in Muscle Stiffness (고유수용성감각 촉진을 위한 나선형 테이핑 방법이 근육 경도 변화에 미치는 즉각적인 효과)

  • Yang, Jae-Man
    • PNF and Movement
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    • v.20 no.3
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    • pp.321-329
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    • 2022
  • Purpose: The purpose of this study was to compare the immediate effect on the change in muscle stiffness in the common extensor muscle (CEM) when using the spiral taping method to promote proprioception. Methods: There were 18 participants in this study. CEM stiffness was measured using a MyotonePRO device with the subject in a sitting position and according to the proprioceptive neuromuscular facilitation (PNF) arm pattern. Elastic tape was used as the material for the three taping methods employed in the study: kinesiotaping (KT), right spiral taping (RST), and left spiral taping (LST). The taping methods were applied to the wrist extensor muscle with elongation position. Additionally, when performing PNF arm patterns, spiral taping in diagonal and spiral directions was used to promote CEM proprioceptors. The change in CEM stiffness was compared with the initial data values. Results: The results of this study were obtained by comparing and measuring changes in CEM stiffness using three different tapings. It was found that the stiffness change of the CEM was significant compared to the initial value, and the increase in stiffness of the CEM after RST application was also significant. Conclusion: The results of this study show that by affecting the strength and activation of the extensor muscle, taping performed through the RST method had the most positive effect on the change in CEM stiffness.

Intervention of Environmental Health Behavior for Pregnant Women: A Scoping Review (임신여성의 환경적 건강행위 중재: 주제범위 고찰)

  • Kim, Hyun Kyoung;Ko, Eun Jung
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.5
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    • pp.321-327
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    • 2022
  • This study explored the environmental health behavior intervention study for pregnant women using a scoping review. The evidence synthesis of intervention methods, research topics, outcome variables, and effectiveness was performed. Eight studies were extracted from the databases of PubMed, Cochrane Library, and RISS. The topics were nutritional interventions and behavioral interventions that can reduce exposure to fine dust, heavy metals, chemicals, and electromagnetic waves to pregnant women. The interventions were conducted through lectures, cartoons, workshops, interviews, messages, and home visits. The effect of the intervention was found to improve the health behaviors of pregnant women and to solve problems in the residential environment. Therefore, the environmental health behavior interventions for pregnant women were effective.

Cationized Lignin Loaded Alginate Beads for Efficient Cr(VI) Removal

  • Jungkyu KIM;YunJin KIM;Seungoh JUNG;Heecheol YUN;Hwanmyeong YEO;In-Gyu CHOI;Hyo Won KWAK
    • Journal of the Korean Wood Science and Technology
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    • v.51 no.5
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    • pp.321-333
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    • 2023
  • In this study, lignin, a lignocellulosic biomass, was chemically modified to produce polyethyleneimine-grafted lignin (PKL) with maximum hexavalent chromium [Cr(VI)] adsorption capacity. Changes in the physicochemical properties due to the cationization of lignin were confirmed through elemental analysis, Fourier transform infrared spectroscopy, and moisture stability evaluation. Alginate (Alg) beads containing PKL (Alg/PKL) were prepared by incorporating cationic lignin into the Alg matrix to apply the prepared PKL in a batch-type water treatment process. The optimal Alg/lignin mixing ratio was selected to increase the Cr(VI) adsorption capacity and minimize lignin elution from the aqueous system. The selected Alg/PKL beads exhibited an excellent Cr(VI) removal capacity of 478.98 mg/g. Isothermal adsorption and thermodynamic analysis revealed that the Cr(VI) removal behavior of the Alg/PKL beads was similar to that of heterogeneous chemical adsorption. In addition, the bulk adsorbent material in the form of beads exhibited adsorption behavior in three stages: surface adsorption, diffusion, and equilibrium.

Change of Balance Ability in Subjects with Pain-Related Temporomandibular Disorders

  • Ja Young Kim;Sang Seok Yeo
    • The Journal of Korean Physical Therapy
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    • v.34 no.6
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    • pp.321-325
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    • 2022
  • Purpose: Temporomandibular disorder (TMD) is a condition defined as pain and dysfunction of temporomandibular joints and masticatory muscles. Abnormal interconnections between temporomandibular muscles and cervical spine structures can cause the changes of postural alignment and balance ability. The aim of this study was to investigate changes in static balance ability in subjects with painrelated TMD. Methods: This study conducted on 25 subjects with TMD and 25 control subjects with no TMD. Pressure pain thresholds (PPTs) of the masseter and temporalis muscles were measured using a pressure algometer. Static balance ability was assessed during one leg standing using an Inertial Measurement Unit (IMU) sensor. During balance task, the IMU sensors measured motion and transfer movement data for center of mass (COM) motion, ankle sway and hip sway. Results: PPTs of masseter and temporalis muscles were significantly lower in the TMD group than in the control group (p<0.05). One leg standing, hip sway, and COM sway results were significantly greater in the TMD group (p<0.05), but ankle sways were not different between group. Conclusion: We suggest pain-related TMD is positively related to reduced PPTs of masticatory muscles and to static balance ability. These results should be considered together with global body posture when evaluating or treating pain-related TMD.

The Association between Bullying Experience related to Clinical Placement and Psychological Well-being in Nursing Students

  • Ren, Liping;Kim, Hyunli;Jung, Mi Sook
    • Research in Community and Public Health Nursing
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    • v.26 no.4
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    • pp.321-329
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    • 2015
  • Purpose: This study aimed to explore the prevalence of bullying and to examine the effect of bullying on psychological well-being including depression, self-esteem, and academic major satisfaction among nursing students during clinical training. Methods: Three hundreds one nursing students who were recruited from three universities in D City were assessed with self-report questionnaires of bullying experience and psychological well-being. Data analyses were performed using the SPSS 21.0 program, which included one-way ANOVA, independent t-test, Pearson's correlation, and multiple linear regression analyses. Results: More than three quarters of the participants experienced bullying during their clinical training, and their experience of being bullied was a significant predictor of psychological well-being even after controlling for perceived academic performance, relationship between nurses and students, teachers' or nurses' help to deal with bullying, and religion. Conclusion: Bullying was an issue among nursing students during clinical placement. Bullying experience yielded negative psychological outcomes associated with high depression, low self-esteem, and low academic major satisfaction. Practical guidelines are required in nursing education to protect students from the possible harm of bullying in clinical settings during training.

Classification of Epilepsy Using Distance-Based Feature Selection (거리 기반의 특징 선택을 이용한 간질 분류)

  • Lee, Sang-Hong
    • Journal of Digital Convergence
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    • v.12 no.8
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    • pp.321-327
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    • 2014
  • Feature selection is the technique to improve the classification performance by using a minimal set by removing features that are not related with each other and characterized by redundancy. This study proposed new feature selection using the distance between the center of gravity of the bounded sum of weighted fuzzy membership functions (BSWFMs) provided by the neural network with weighted fuzzy membership functions (NEWFM) in order to improve the classification performance. The distance-based feature selection selects the minimum features by removing the worst features with the shortest distance between the center of gravity of BSWFMs from the 24 initial features one by one, and then 22 minimum features are selected with the highest performance result. The proposed methodology shows that sensitivity, specificity, and accuracy are 97.7%, 99.7%, and 98.7% with 22 minimum features, respectively.

The Effect of Motives for Using IPTV Advertising on Using Behavior of IPTV Advertising (IPTV 광고 이용동기가 IPTV 광고 이용행동에 미치는 영향에 관한 연구)

  • Choi, Min-Wook
    • Journal of Digital Convergence
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    • v.11 no.8
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    • pp.321-330
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    • 2013
  • This study attempts to understand the motives for using IPTV advertising and to understand the impact of the motivations on using behavior of IPTV advertising. To understand the motives for using IPTV advertising, a survey was conducted after pre-test for questionnaire design. The Composition of motive factors were ascertained through factor analysis. The analysis produced 4 dimensions of motives for using IPTV advertising, including 'economic motivation', 'information', 'advertising', and 'passing time/habit'. Each motive impacted on each using behavior differently.