본 연구의 목적은 최근 국내외 사회복지분야에 새롭게 소개된 질적 해석적 메타통합(QIMS)을 적용하여 한국노인이 인식하는 삶의 질에 관한 새로운 의미를 탐색하는 것이다. 한국노인의 삶의 질은 재발성 노인질환, 생활습관과 선택, 인구고령화와 기대수명 연장, 급속한 사회변화 등 다양한 요인에 의해 부정적 또는 긍정적인 영향을 받는다. 본 연구는 질적 해석적 메타통합의 체계적인 과정을 통해 한국노인의 삶의 질과 관련된 위험요인과 보호요인을 강조 하고 탐색하는 것을 전제로 기존의 개별 질적 연구결과를 통합한 후 재해석하여 종합하였다. 연구결과는 다음과 같다. (1) 다양한 삶의 경험들, (2) 안녕한 상태 유지하기, (3) 스스로 더 잘 돌봄, (4) 삶에 대한 새로운 관점 갖기를 포 함한 4개의 독립적이고 포괄적인 주제가 창출되었다. 이러한 연구결과를 토대로 향후 한국노인의 특성을 고려한 삶의 질 이론 개발에 기여할 뿐만 아니라 노인복지, 장애인복지 등 사회복지실천영역의 연구자 및 전문가들이 노인의 삶의 질과 관련된 유지 및 향상요인을 강화하는데 더 큰 이해를 제공하고자 한다.

Herein, a series of g-C3N4 modified Bi2MoO6 nanocomposites using Bi2MoO6 and melamine as original materials are fabricated via sintering process. For presynthesis of Bi2MoO6 an ultrasonic-assisted hydrothermal technique is researched. The structure and composition of the nanocomposites are characterized by Raman spectroscopy, X-ray diffraction (XRD), and high-resolution field emission scanning electron microscopy (SEM). The improved photoelectrochemical properties are studied by photocurrent density, EIS, and amperometric i-t curve analysis. It is found that the structure of Bi2MoO6 nanoparticles remains intact, with good dispersion status. The as-prepared g-C3N4/Bi2MoO6 nanocomposites (BMC 5-9) are selected and investigated by SEM analysis, which inhibits special morphology consisting of Bi2MoO6 nanoparticles and some g-C3N4 nanosheets. The introduction of small sized g-C3N4 nanosheets in sample BMC 9 is effective to improve the charge separation and transfer efficiency, resulting in enhancing of the photoelectric behavior of Bi2MoO6. The improved photoelectronic behavior of g-C3N4/Bi2MoO6 may be attributed to enhanced charge separation efficiency, photocurrent stability, and fast electron transport pathways for some energy applications.

This research aims to study the effect of impregnation ratio and activation temperature on microporous development of activated carbon (AC). Rubberwood chips, which are wasted from home furnishing industry, were used as precursors for synthesized of activated carbon by chemical activation employing Potassium hydroxide (KOH) as activation agent. Rubberwood char was carbonized at 400 °C for 1 h under inert gas. In this experiment, the rubberwood chars were impregnated with KOH solution by 1:1–3 (char: KOH) impregnation ratio for 24 h, then the samples were activation at 600–800 °C. Surface area, pore volume, micropore volume, pore size distribution, adsorption isotherm and porous structure were analyzed in this experiment to identify the properties of derived activated carbon. According to the investigation, the activated carbon, activated at 800 °C with impregnation ratio of 1:3, demonstrated the highest surface area, pore volume and micropore volume as 1491.75 m2/g, 0.6777 cm3/g, and 0.5813 cm3/g, respectively. Its average pore size was 1.82 nm and it also showed type I adsorption isotherm which indicates as microporous solid.

This work reveals a modified method for the preparation of activated carbon (P-ACA) using low-cost materials (mix natural asphalt: polypropylene waste). The P-ACA was prepared at 600 °C by assisting KOH and HF. The morphological variations and chemical species of the P-ACA were characterized using SEM–EDX and FTIR. The active surface area, density and ash content of the P-ACA were also investigated. Adsorption properties of P-ACA were used for the thermodynamic and kinetic study of 4-((2-hydroxy naphthalenyl) diazenyl) antipyrine (HNDA), which was prepared as a novel azo dye in this work. The optimal conditions (initial concentration, adsorbent dose, contact time and temperature) of the adsorption process were determined. Adsorption isotherms (Freundlich and Langmuir) were applied to the experimental data. These isothermal constants were used to describe the nature of the adsorption system, and the type of interaction between the dye and the P-ACA surface. The results have indicated that the mixture (Natural asphalt-polypropylene waste) is efficient for the synthesis of P-ACA. The synthesized P-ACA demonstrates the presence of pores on the surface with various diameter ranges (from 1.4 to 4.5 μm). Furthermore, P-ACA exhibits an active surface area of 1230 m2 g−1, and shows a high adsorption capacity for HNDA.

이 연구는 화장품에 사용가능한 촉매제를 사용하여 콜로이달 골드를 합성하는 제조법과 이를 이용한 피부 개선 효과를 가진 항노화 엠플에 응용하였다. 하이드로젠테트라클로로아우레이트테트라하이드레이트에 아스코르빅애씨드, 소듐보로하이드라이드를 환원촉매제로 사용하여 나노 콜로이드를 합성하였다. 촉매제인 아스코르빅애씨드의 함량의 질량이 증가될수록 입자가 작아지는 것을 확인하였다. 반면 소듐 보로하이드라이드의 질량이 증가될수록 입자크기는 증가하는 경향을 보였다. 콜로이달 골드 반응 속도를 조절하기 위하여, 잔탄검과 하이드록시에칠셀룰로오스를 사용하여 100~500 nm의 입경분포를 가진 입자를 얻을 수 있었다. 최적의 합성조건은 18℃, 20~75 mmHg의 감압상태, 교반속도 10~50rpm, 1~4시간동안 반응하여 획득할 수 있었다. 합성된 콜로이달 골드의 외관은 진한 핑크색, pH=5.5, 비중은 1.0032, 점도는 80~310 cps로 특이한 고유 냄새를 가지고 있었다. 스킨케어 화장료의 응용으로, 안티에이징 엠플을 개발하였고, 이를 이용한 다양한 처방과 제형개발에 활용될 것으로 기대한다.

Y2O3:Eux (x = 0.005, 0.01, 0.02, 0.03, 0.05, 0.1 mol) phosphors are synthesized with different concentrations of Eu3+ ions by solvothermal method. The crystal structure, surface and optical properties of the Eu doped Y2O3 phosphors are investigated using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and photoluminescence (PL) and photoluminescence excitation (PLE) analyses. From X-ray diffraction (XRD) results, the crystal structure of the Eu doped Y2O3 phosphor is found to be cubic. The maximum emission spectra of the Eu doped Y2O3 phosphors are observed at 0.05 mol Eu3+ concentration. The photoluminescence of 615 nm in the Eu doped Y2O3 phosphors is associated with 5D0 → 7F2 transition of Eu3+ ions. The decrease in emission intensity of 0.1 mol Eu doped Y2O3 is interpreted by concentration quenching. The International Commission on Illumination (CIE) coordinates of 0.05 mol Eu doped Y2O3 phosphor are X = 0.6547, Y = 0.3374.

Magnetic nanoparticles have a significant impact on the development of basic sciences and nanomedical, electronic, optical, and biotech industries. The development of magnetic structures with size homogeneity, magnetization, and particle dispersibility due to high-quality process development can broaden their utilization for separation analysis, structural color optics using surface modification, and energy/catalysts. In addition, magnetic nanoparticles simultaneously exhibit two properties: magnetic and plasmon resonance, which can be self-assembled and can improve signal sensitivity through plasmon resonance. This paper reports typical examples of the synthesis and properties of various magnetic nanoparticles, especially magnetoplasmonic nanoparticles developed in our laboratory over the past decade, and their optical, electrochemical, energy/catalytic, and bio-applications. In addition, the future value of magnetoplasmonic nanoparticles can be reevaluated by comparing them with that reported in the literature.

본 연구에서는, 주위 산도나 근적외선과 같은 외부에서 주어지는 자극에 의하여 내부 탑재 약물의 방출을 조절할 수 있는, 자극 응답성 키토산(Cs) 하이드로겔를 합성하고 그것의 특성과 성능을 조사하였다. 우선 Cs와 carbic anhydride의 개 환반응에 의하여 노르보닐(Nb) 작용기가 도입된 Cs 유도체(Cs-Nb) 를 합성하였으며, methyltetrazine-amine과 selenolactone의 반응에 의하여 테트라진 (Tz) 작용기가 양 말단에 도입된 가교제(Se-Tz)를 합성하였다. Cs-Se 하 이드로겔은 CS-Nb와 Se-Tz 사이의 클릭반응에 의하여 빠르게 형성할 수 있었으며, Nb/Tz 반응 몰비 변화로서 가교도를 조절하였다. 하이드로겔의 가교도와 용액의 산도가 낮을수록 하이드로겔의 팽윤도가 높아졌으며, 하이드로겔의 내부구조가 다공성을 가짐을 SEM 단면 분석 결과 확인할 수 있었다. Ciprofloxacin hydrochloride monohydrate 약물을 탑재한 하이드로겔은 pH 5.2의 PBS용액에서 pH 3.7에 비하여 높은 약물 방출을 나타내었다. 또한 근적외선 조사에 의하여 약물 방출을 빠르게 유도할 수 있었다.

2-브로모메틸-1,3-디옥솔란을 이용한 2-에티닐피리딘의 중합을 통하여 측쇄에 디옥솔란 치환기를 갖는 새로운 이온성 공액구조 고분자를 합성하였다. 별도의 촉매없이도 중합반응이 잘 진행되어 높은 수율의 중합체를 얻을 수 있었다(76%). 합성한 고분자의 분자구조를 여러 가지 분석장비를 사용하여 분석한 결과 1,3-디옥솔란 부분을 갖는 설계한 공액구조 고분자임을 확인하였다. 고분자의 적외선분광분석 스펙트럼에서는 2110 cm-1 와 3293 cm-1에 서 관찰되었던 2-에티닐피리딘의 아세틸렌 특성피크를 보여주지 않는 대신 1620 cm-1 인근에서 공액이중결합의 탄소-탄소 이중결합의 특성 피크를 보다 강하게 보여주었다. 합성한 고분자의 전기전도도 및 전기-광학적 특성을 측정하고 분석하였다. 요오드로 도핑한 고분자의 전기전도도는 1.82 x 10-3 S/cm 였다.

Anti-melanogenesis and skin anti-wrinkle effects of methanol (ME) and hot water (HE) extracts from the fruiting bodies of Ganoderma applanatum were investigated in this study. The total phenolic contents of the ME and HE of the mushroom were 11.68 and 3.15 μg GAEs/mg, respectively, whereas the total flavonoid contents of the ME and HE were 21.82 and 2.69 μg QEs/mg, respectively. The survival rate of B16-F10 murine melanoma cells treated with 750 μg ME and HE were 83.46% and 85.54%, respectively, thereby suggesting that mushroom extracts were slightly cytotoxic at the tested concentration. The in vitro tyrosinase inhibition by ME (83.15%) and HE (83.44%) was significantly lower than that of kojic acid (99.61%), the positive control, at 2.0 mg/mL. Although the inhibition of cellular melanin synthesis in B16-F10 melanoma cells by 2.0 mg/mL of ME (50.24%) and HE (51.24%) was lower than that of arbutin (64.84%), the inhibition by both ME and HE was higher than 50%. Collagenase inhibition by HE was comparable to 2.0 mg/mL epigallocatechin (EGCG), the positive control; however, elastase inhibition by ME and HE was lower than that of EGCG at the concentration tested. The results showed that the fruiting bodies of G. applanatum had good anti-tyrosinase, good anti-collagenase, and moderate anti-elastase activities, which might be useful for developing novel skin-whitening and anti-wrinkle agents.

In this study, the MoS2 nanoparticles grown on crumpled 3D graphene microball (3D GM–MoS2) was synthesized using a microfluidic droplet generator with thermal evaporation-driven capillary compression and hydrothermal reaction. The morphology and size of 3D GM–MoS2 are controlled by the concentration of nano-sized graphene oxide (GO) and the flow rate of oil phase on the droplet generator. The 3D GM–MoS2 with fully sphere-shape and uniform size (~ 5 μm), and homogeneous growth of MoS2 nanoparticles could be synthesized at the flow rate of the oil phase of 60 μL/min with the optimized GO concentration of 1.0 mg/mL, and ( NH4)2MoS4 concentration of 2.0 mg/mL.

Oil spills into ocean or coastal waters can result in significant damage to the environment via pollution of aquatic ecosystems. Absorbents based on reduced graphene oxide (rGO) foams have the capacity to remove minor or major oil spills. However, conventional chemical synthesis of rGO often uses petrochemical precursors, potentially harmful chemicals, and requires special processing conditions that are expensive to maintain. In this work, an alternative cost-effective and environmentally friendly approach suitable for large-scale production of high-quality rGO directly from used cooking sunflower oil is discussed. Thus, produced flaky graphene structures are effective in absorbing used commercial sunflower oil and engine oil, via monolayer physisorption in the case of used sunflower and engine oils facilitated by van der Waals forces, π–π stacking and hydrophobic interactions, π-cation ( H+) stacking and radical scavenging activities. From adsorption kinetic models, first-order kinetics provides a better fit for used sunflower oil adsorption (R2 = 0.9919) and second-order kinetics provides a better fit for engine oil adsorption (R2 = 0.9823). From intra-particle diffusion model, R2 for USO is 0.9788 and EO is 0.9851, which indicates that both used sunflower and engine oils adsorption processes follow an intra-particle diffusion mechanism. This study confirms that waste-derived rGO could be used for environmental remediation.

Nitrogen-doped carbon dots (N-CDs), derived from the biomass (anthocyanin), are the novel additive to the nanocarbon materials, which is expected to bring a wide spectrum of novel applications. Moreover, metallic oxides are emerging for their unique potential for electrocatalysis. Herein, we report the synthesis of N-CDs for the selective detection of Fe3+ with a limit of detection of 2.57 μM in the range of 5–60 μM using ethylenediamine and H2O2 by a hydrothermal method. The obtained N-CDs displayed a spherical morphology with a particle size range of 2–7 nm and emitted blue luminescence at 394 nm under excitation at 319 nm. Meanwhile, we have demonstrated the fabrication of cost-efficient electrocatalysts for oxygen evolution reaction (OER) in an alkaline medium, employing N-CDs. Owing to the successful incorporation of N-CDs into NiO nanospheres, the resulting N-CDs/NiO with large surface areas, fast charge transfer, and increased conductivity vastly improved the catalytic activity. Remarkably, the optimal of N-CDs/NiO composite requires the overpotential of only 380 mV at a current density of 10 mA cm− 2 and a relatively low Tafel slope of 57.96 mV dec− 1 compared with pure NiO. These results open up a facile route for the application of N-CDs and offer prospects for CD-metal hybrids as high OER catalysts in electrochemical energy devices.

We report the rapid single-step flame synthesis of hydrophobic carbon layers (C-layers) on the surface of stainless-steel (SS) substrates using vaporized biodiesel as the fuel. A co-flow canola methyl ester/air diffusion flame is used to generate a hydrophobic monolayer on the surface of the metal substrate upon its insertion into the reaction zone. Carbon deposition on the surface of the SS substrates varies by changing the SS disk’s position in the post-flame, and by varying its exposure time. The thickness and mass of the flame-formed monolayer varied depending on the substrate’s insertion point into the flame. However, the variation of mass did not significantly impact the C-layer’s uniformity or hydrophobicity. We hypothesize that a small “inner-cone” of the biodiesel flame along with a high soot propensity can result in an ideal medium to form uniform hydrophobic C-layers of unique hierarchical surface structure. This is supported by introducing SS substrates in methane/air flames formed using the same co-flow burner. The hydrophobic property of the carbon deposits was quantified by measuring the contact angle of water droplets placed on the film’s surface. A water droplet drop test was conducted on the flame-formed hydrophobic layers to study their wettability property.

본 연구는 B16F10 melanoma 세포에서 산딸기 잎 추출물(Rubus crataefifolius Leaf Extract, RCLE)의 멜라닌 생성 억제 효과를 확인하고자 수행되었다. α-MSH로 자극한 B16F10 melanoma 세포에서 멜라닌 함량과 tyrosinase 활성, 멜라닌 생성관련 효소들인 TRP-1, TRP-2 및 MITF의 단백질 발현 수준을 조사하였고 이에 대한 RCLE의 효과를 검증하였다. RCLE는 tyrosinase 활성과 멜라닌 생성을 효과적으로 억제하였고 멜라닌 생성 경로에 관여하는 PKA와 CREB의 인산화와 MITF의 발현을 억제하였으며 멜라닌 생성 관련 단백질의 발현을 하향 조절하였다. 이러한 결과는 RCLE가 MITF 발현을 억제하여 α -MSH로 자극된 멜라닌 합성을 억제한다는 것을 보여준다. 따라서 이러한 연구결과는 RCLE가 과도한 멜라닌 생성으로 인한 색소 침착을 완화시킬 수 있는 기능성 화장품 소재로 활용될 수 있음을 시사한다.