검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 2,950

        328.
        2022.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        By polymerizing acrylonitrile in the presence of ammonium persulfate as an initiator and Pterocladia capillacea-activated carbon (P-AC) as a filler, a composite material polyacrylonitrile/Pterocladia capillacea-activated carbon (PAN/P- AC) was developed. By reacting hydroxylamine with the composite's nitrile groups, the prepared composite was functionalized by amidoximation. FTIR spectrometry, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and Brunauer–Emmett–Teller (BET) analysis were all applied to thoroughly characterize the fabricated adsorbent. For the treatment of Cr(VI) ions from synthetic solutions, the adsorption properties of amidoximated polyacrylonitrile/Pterocladia capillacea-activated carbon (PAO/P-AC) were investigated. The pH effect, uptake kinetics, adsorption isotherms, and thermodynamics studies were used to characterize adsorption properties. As a kinetic model analysis, the data confirmed that the pseudo-second-order rate equation matched well the adsorption process. With coefficients of determination (R2) of 0.9998, the Tempkin isotherm model had the lowest error, suggesting that it is the best fitted model to describe this adsorption mechanism. Thermodynamic parameters demonstrated that Cr(VI) adsorption was endothermic.
        6,000원
        329.
        2022.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The implanted electronic devices require a stable, continuous, and long-lasting energy source to function correctly. These devices are powered by alkaline batteries and lithium ions. When used in implantable or wearable devices, these batteries can pose a threat to human health and the environment. Because of these factors, implantable and wearable devices using enzyme biofuel cells (EBFCs) are receiving a lot of attention. These EBFCs use human physiological fluid to provide longterm control for these devices. Carbon nanomaterials have successfully been demonstrated in enzymatic biofuel cells to improve applications by increasing current and power density; they have the potential to enhance EBFC efficiency. This review summarizes the fundamental process of EBFC compounds based on carbon nanomaterials before delving into the most recent advancements that have been tested and used as implantable and wearable self-power sources.
        5,200원
        330.
        2022.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Nanomaterials (NMs) are gradually becoming pervasive in the modern world, entering every application for improving the quality of life. Multifaceted uses of NMs in curing diseases, biomedical instrumentation, bioimaging, drugs, and gene delivery, display devices, nanosensors, and biomarkers in several fields ranging from agriculture to industries, healthcare, and environment, have been well recognized. Carbon-based nanomaterials (CNMs) constitute a major type of NMs with broad-spectrum applications including their uses in agriculture. These are synthesized in large quantities via synthetic and biological approaches. Biological approaches are gaining appreciation and momentum, owing to the advantages associated with them, major being their environment friendly or ‘Green’ nature. This topical review focuses on the preparation of CNMs using natural resources, i.e., using the Green Nanotechnology. The up-to-date compilation presented here includes most of the popular green technological methods of producing the CNMs and their immediate uses as anticancer agents, in bio-labelling, as biosensors, in bio-remediation, in cell imaging, in fluorescent inks, and fluorescent dyes, as plant growth inducing agents, in nano-probes, in light-emitting devices and other applications. It is intended to update the reader with the state-of-the-art knowledge about the green technological methods for synthesizing CNMs, their uses, current trends, challenges, and future outlook on the topic.
        6,900원
        331.
        2022.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Chinese cabbage or pakchoi (Brassica Rapa subsp. Chinensis) is one of the most popular vegetables in Korea. It is grown and consumed throughout the year because it has many benefits. This study reports on the growth performance of pakchoi grown in the hydroponic system using a Food Juke Box (FJB) under different light compositions. The chlorophyll content (CC), root fresh weight (RFW), and shoot fresh weight (SFW) were measured. Further, various vegetation indices (VIs), such as modified chlorophyll absorption in reflectance index (MCARI1), normalized difference vegetation index (NDVI), optimized soil-adjusted vegetation index (OSAVI), and structure insensitive pigment index (SIPI), were employed to predict SFW. The study results indicated a significant increase in the CC of pakchoi with different light treatments compared with the control. The CC was highest under treatment with 70% white light, 20% blue light, and 10% red light (T1) than under treatment with 50% white light, 30% blue light, and 20% red light (T2). All used VIs showed significant differences with different light combination treatments. There was no significant change in RFW and SFW between the control and T1. However, a significant reduction in RFW and SFW was observed in T2 compared with the control. A comparison between T1 and T2 demonstrated that RFW and SFW were increased by 23% and 25%, respectively, compared with those in T2. The correlation result showed that SFW had a significant positive correlation with RFW (0.76***). Further, a significant negative correlation was observed with OSAVI (−0.25*), MCARI1 (−0.54***), and CC (−0.19*). In conclusion, our findings implied that different light combinations in pakchoi affected the photosynthetic pigments although they did not improve SFW. This research will pave the way for pakchoi production in hydroponics using smart farming FJB. This will further promote plant development, especially for domestic consumption, and help fulfill the growing demand for leafy vegetables.
        4,000원
        332.
        2022.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Extracellular vesicles (EVs) are nanovesicles that carry bioactive cargoes of proteins, lipids, mRNAs, and miRNAs between living cells. Their role in cellular communication has gained the attention of several research reports globally in the last decade. EVs are critically involved in sperm functions, oocyte functions, fertilization, embryonic development, and pregnancy. The review summarizes the state-of-theart of EVs research in the diagnostic and therapeutic (theranostic) potentials of the EVs during the pregnancy that might provide a solution for gestational disturbances such as implantation failure, maternal health problems, gestational diabetes, and preeclampsia. EVs can be found in all biological fluids of the fetus and the mother and would provide a non-invasive and excellent tool for diagnostic purposes. Moreover, we provide the current efforts in manufacturing and designing targeted therapeutics using synthetic and semi-synthetic nanovesicles mimicking the natural EVs for efficient drug delivery during pregnancy.
        4,200원
        333.
        2022.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this work, the sulfonic acid group was introduced into the resorcinol–formaldehyde (RF) microspheres by the addition of p-phenolsulfonic acid during the polycondensation process of RF. The hydrophilicity of the sulfonated RF allowed KOH to infiltrate inside the microspheres, which enhanced the formation of mesopores in the carbon microspheres during the activation process by KOH. SEM and TEM observations and N2 adsorption measurements verified the formation of abundant mesopores in the porous carbon microspheres. The BET surface area of these mesoporous carbons exceeded 2000 m2/ g. In 17 m NaClO4 “water-in-salt” (WIS) electrolyte-based supercapacitor, the synthesized mesoporous carbon exhibited high specific capacitance of 170 F/g at current density of 0.5 A/g, comparable to those in regular KOH electrolyte. When graphite was used as current collectors, the symmetric cell could operate at 2.5 V, and the mesoporous carbon exhibited an energy density of 43 Wh/kg at power density of 0.25 kW/kg, and 25 Wh/kg at power density of 6.25 kW/kg, respectively, which were superior to those using Pt or stainless steel as current collectors. The mesoporous carbon/graphite was an excellent electrode in new-generation “WIS” electrolyte-based high-voltage supercapacitor due to their high energy and power density.
        4,000원
        334.
        2022.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Sugarcane bagasse has been used as a substrate for the development of microporous nano-activated carbons for the treatment and elimination of dissolved materials from aquatic environment. The activated carbon was produced using chemical activation in one-step method with zinc chloride ( ZnCl2) as the activating agent at a carbonization temperatures range from 500 to 900 °C. The effects of temperature and time of carbonization on the activated carbon product properties were thoroughly studied. The activated carbons that resulted were characterized using the N2 adsorption/desorption isotherms, Brunauer–Emmett–Teller method (BET), pore property analysis, micropore (MP) surface area, t-plot surface area, TGA, FTIR, SEM, TEM, and EDX analyses. The prepared activated carbon’s point of zero charge, Boehm titration process, iodine removal percentage, and methylene blue number were also investigated. The prepared activated carbon’s maximum surface area was achieved using a 2/1 impregnation ratio (dried sugarcane bagasse/ZnCl2) at 600 °C temperature of carbonization and 60 min residence time. 1402.2 m2/ g, 0.6214 and 1.41 cm3/ g, respectively, were the largest surface area, total pore volume, and micropore volume. As the activation temperature increased, the total pore volume increased and the BET study measured a pore diameter of 0.7 nm and a mean pore diameter of 1.77 nm.
        5,700원
        335.
        2022.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Diamond-like nanocomposite (DLN) has become a promising thin film for many fields of applications due to its unique and tunable properties. However, low optical bandgap and thermal stability limits its application in many fields particularly as antireflection coating on solar cell. In the present study, the DLN thin film has been deposited using a mixed liquid precursor by rf-PECVD process. Surprisingly the presence of nc-C60 in FCC structure in DLN matrix has been observed. The degree of crystallinity and diameter of C60 have been increased significantly after annealed at 850 °C. The film has been annealed at 850 °C to primarily investigate its feasibility as antireflection coating (ARC) in compatible with industrial solar cell fabrication process. The refractive index and optical bandgap of the film were around 1.80 and 4.10 eV, respectively. Moreover, the optical bandgap has decreased to some extent to 3.92 eV even after annealing at such high temperature. The high SiOx at% and embedded nc-C60 enhanced the optical transparency and thermal stability of the DLN film. The solar-weighted average reflection of DLN-coated textured silicon was reduced significantly to 1.91%. The C60 embedded DLN film has a great potential to apply in different optoelectronic devices especially in solar cell as ARC.
        4,000원
        336.
        2022.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The production of macroalgae-derived adsorbent is of great importance to realize the idea of treating pollutants with invaluable renewable materials. Herein, a novel meso-micro porous nano-activated carbon was prepared from green alga Ulava lactuca in a facile way via chemical activation with zinc chloride. The resultant activated carbon possesses a significant specific surface area 1486.3 m2/ g. The resulting activated carbon was characterized and investigated for the adsorption of Direct Red 23 (DR23) dye from an aqueous environment. Batch method was conducted to study the effects of different adsorption processes on the DR23 dye adsorption from water. Isotherms and kinetics models were investigated for the adsorption process of DR23 dye. It was found that the adsorption data were well fitted by Langmuir model showing a monolayer adsorption capacity 149.26 mg/g. Kinetic experiments revealed that the adsorptions of DR23 dye can be described with pseudo-secondorder model showing a good correlation (R2 > 0.997). The prepared activated carbon from Ulava lactuca was exposed to a total of six regeneration experiments. The regeneration result proved that the fabricated activated carbon only loses 19% of its adsorption capacity after six cycles. These results clearly demonstrated the high ability of the obtained active carbon to absorb anionic dyes from the aqueous environment.
        4,900원
        337.
        2022.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Fluorescent nanostructures based on carbon, or carbon dots, are attracting much attention and interest because of their diverse properties which can be applied in several fields of knowledge, such as optics, biomedicine, environmental research, among others. Such properties are in part, derived from its intrinsic luminescence from tunable functional groups. In this work, we produced carbon nanodots (CND) using agro-industrial residues, such as Lolium perenne and malt bagasse. The methods used were conventional hydrothermal syntheses and microwave-assisted hydrothermal synthesis. To the best of our knowledge, this is the first time that carbon dots synthesized from this ryegrass type are reported. The synthesis methods were one step (no catalyst, base, or acid were added for passivation), and the functional groups responsible for the luminescence and high solubility in water were identified by infrared spectroscopy, being mainly C=O, C–OH, C–N, and N–H. According to our theoretical studies, the C=O group introduced a new energy level for electronic transitions that can affect the emission properties. Fluorescence images of osteoblasts using CNDs were acquired and their chelating property towards Pb2+ and Cr6+ detection was tested.
        4,200원
        338.
        2022.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study examined the effects of hot deboning and the irradiation of raw pork on the physicochemical properties of pork sausages. Pigs were deboned with a carcass (loin surfaces) temperature of 5℃ (cold) or 15℃ (hot). Each deboned raw pork loins were then irradiated at 0 kGy or 4 kGy. Emulsion-type sausages were prepared from each treated meat with other ingredients including fat, ice, salt, phosphate, and seasoning powder. Then sausage products were analyzed for their physiochemical properties and microbial spoilage up to 10 days. Emulsion stability of sausage products with hot deboning was better than the cold carcass up to three days. Sausage products with irradiated hot carcasses showed less cooking loss than from non-irradiated carcasses on day 10. Hardness, gumminess, and chewiness of the sausages decreased significantly with increasing storage time for all sausage products (p<0.05), but the sausage products with irradiated hot carcasses showed a smaller reduction compared with non-irradiated. Lipid oxidation was not significantly different in the sausage products with hot or cold deboning (p>0.05), but the sausage products from non-irradiated meats showed changes from 0.43 to 1.59 (MDA mg/kg of meat) in 10 days (p<0.5). Total plate count and E. coli count were significantly lower in the sausage products from irradiated meat (p<0.05). Finally, irradiating hot deboned meat at 4 kGy can be an excellent alternative for producing raw meat for sausages with promising microbiological and physicochemical properties.
        4,000원
        339.
        2021.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This work describes the facile synthesis of silver nanoparticle-decorated zinc oxide nanocomposite through a simple glycol reduction method. The silver nanoparticle-decorated zinc oxide nanocomposite-based pencil graphite electrode has been validated as a perceptive electrochemical sensing podium towards nitrite. The morphology of the prepared nanocomposite has been characterized via specific spectroscopic and electrochemical techniques. The sensor exhibits a notable enhancement in the cyclic voltammetric response to nitrite oxidation at an ideal peak potential of 0.76 V in pH 6.0 acetate buffer. Under optimum conditions of nitrite directly expanded with their concentration in the range from 30 to 1400 μM with a detection limit of 14 μM.
        4,600원
        340.
        2021.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In the present study, a novel electrochemical sensor for acetaminophen (AMP) which included quantum graphitic carbon nitride dots, g-C3N4QDs, was designed and conducted with molecular imprinted polymer (MIP). First, bulk g-C3N4 was generated with direct thermal polycondensation of melamine. After the treatment of the acidic solution containing H2SO4: HNO3 (1:1, v:v), the heating treatment at 200 °C on the dispersion provided g-C3N4QDs. In this respect, for nanomaterial characterization, some spectroscopic approaches were performed including Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) as well as electroanalytical methods such as electrochemical impedance (EIS) and cyclic voltammetry (CV). In accordance with the aims of the study, AMP imprinted electrode was formed after high electrocatalytic performance and linear range of 1.0 × 10– 11–2.0 × 10– 8 M and the LODs of 2.0 × 10– 12 was achieved. Eventually, an AMP-printed sensor was also used for AMP identification in pharmaceutical samples.
        4,300원