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        검색결과 46

        1.
        2023.05 구독 인증기관·개인회원 무료
        The removal of aqueous pollutants, including dye molecules from wastewater remains one of the pressing problems in the world. Because of chemical stability and conjugated structure, dye molecules cannot be easy decomposed by heat with oxidizing reagents such as H2O2 and light. The most common representative of widespread organic pollutant is methylene blue (MB) with molecular formula C16H18ClN3S, which is important colorant and used in various chemical and biological production industries and causes serious environment problems. Porous materials, including MOFs (metal-organic frameworks) have been applied for efficient MB photocatalytic degradation. However, one of the main barriers to using most MOFs to break down aromatic organics is wide band gap energy, which means that the catalyst can exhibit high photocatalytic performance only under UVlight irradiation. Moreover, most MOFs usually show the poor water stability of frameworks, which tend to dissolve in water with total destruction. In this work we report about two new copper based MOFs with high photocatalytic properties for efficient MB degradation from wastewater under UV-light and natural sunlight. Time, required for 100% MB degradation, equals 7 minutes under UV (source 4 W 254 nm VL-4.LC UV-lamp) and 60 minutes under natural sunlight irradiation in the presence of H2O2. Crystal structure information is provided using single crystal X-ray diffraction data. The composition and comparative characteristics of MOFs are given using powder X-ray diffraction, UV–visible diffuse reflectance spectroscopy, UVvisible spectroscopy and Fourier-transform infrared spectroscopy.
        3.
        2021.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Here, a novel nitrogen-doped carbon nano-material (N-CGNM) with hierarchically porous structure was prepared from spent coffee ground for efficient adsorption of organic dyes by a simple one-step carbonization process (the uniform mixture consists of spent coffee ground, urea, and CaCl2 with the ratio of 1:1:1, which was heated to 1000 °C with a rate of 10 °C min− 1 and held at 1000 °C for 90 min in N2 atmosphere to carry out carbonization, activation, and N-doping concurrently). The morphology and structure analysis show that the prepared N-CGNM exhibits hierarchical pore structure, high specific surface area (544 m2/ g), and large numbers of positively charged nitrogen-containing groups. This unique structure and chemical composition endow N-CGNM with an excellent adsorption capacity toward anion Congo red (623.12 ± 21.69 mg/g), which is obviously superior to that (216.47 ± 18.43 mg/g) of untreated spent coffee ground-based carbon nano-materials (CGM). Oppositely, the adsorption capacity of N-CGNM towards cation methylene blue is inferior to that of CGM due to the existence of electrostatic repulsion. These findings show a great guidance for the development of low-cost but efficient selective adsorbent.
        4,300원
        4.
        2021.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Thermal reduction of graphite oxide (GO) is considered as a prospective method for the preparation of high-performance graphene-based materials. However, this method has certain limitations, and the major is that this exothermic process is difficult to control. In this research, we focused on the kinetic studies of the reduction of graphite oxide using non-isothermal differential calorimetry (DSC) method. Six GO nanocomposites with dyes were tested to study the shift in kinetic parameters. The apparent reaction order is determined to be ca 0.7 for the thermal decomposition of pure GO, while in the presence of dye molecules it increases sometimes reaching a value of 2.0 for higher dye concentrations. Decisively, the thermal decomposition of pure GO can be presented as an intermediate between a zero- and first-order reaction, while the introduction of dye molecules turns a certain part of the energy consumption via the bimolecular pathway. Our research revealed that the process of GO thermal decomposition can be operated and properties of the final product (reduced graphene oxide (rGO) and its derivatives) can be adjusted more precisely using additive molecules, which interact with GO sheets.
        4,600원
        5.
        2021.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This work reports utilization of apple leaves as a source of activated carbon. Activated carbon from apple leaves is prepared by two different methods, thermal activation where AC1 is obtained and chemical activation using H3PO4 and ZnCl2 where AC2 and AC3 are obtained, respectively. XRD analysis revealed that all types of prepared ACs have a semi-crystalline nature with a mean crystallite size of 13, 21.02, and 39.47 nm for AC1, AC2, and AC3, respectively. To identify the most suitable desorption temperature, the exothermic behavior was discovered for the three types of ACs by DSC. The exothermic onset temperatures are 340 °C, 200 °C, 400 °C, or AC1, AC2, and AC3, respectively. The point of zero charge for the three types of ACs is 8.6, 7.3, and 2.5 for AC1, AC2, and AC3, respectively. The BET surface area analysis data demonstrated that mesoporous structure was developed in AC1 and AC2, while a microporous structure was developed in AC3. Quantum chemical calculations for ACs is carried out using Density Functional Theory (DFT). Application of the prepared ACs in adsorption of basic dye C.I. base blue 47 is studied. The maximum removal efficiency was 65.1%, 96% and 99% for AC1, AC2, and AC3, respectively under the influence of different operating aspects. Adsorption data are modeled by Langmuir, Freundlich, and Temkin isotherms. The data revealed that adsorption of basic dye C.I. base blue 47 on AC1 follows Langmuir isotherm and adsorption on AC2 and AC3 follows Freundlich isotherm.
        4,900원
        7.
        2020.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Carbonaceous materials are considered as potential adsorbents for organic dyes due to their unique structures which provide high aspect ratios, hydrophobic property, large efficient surface area, and easy surface modification. In this work, graphene nanoribbons (GNRs) were prepared by atomic hydrogen-induced treatment of single-walled carbon nanotube (SWCNTs), which inspire the idea of cutting and unzipping the SWCNTs carpets with the modified in molecules prevent because of the unfolding of the side-walls. The unfolded spaces and uniform vertical arrangement not only enhance the active surface area, but also promote the electrostatic and π–π interactions between dyes and GNRs. The improved adsorption capacity of GNRs beyond original SWCNTs can be determined by the adsorption kinetics and isotherm, which are evaluated through adsorption batch experiments of the typical cationic methylene blue (MB) and anionic orange II (OII) dye, respectively. It is shown that the adsorption kinetics follow a pseudo second-order model while the adsorption isotherm could be determined by Langmuir model. The results reveal that the maximum adsorption capacities of GNRs for MB and OII are 280 and 265 mg/g, respectively. The GNRs present the highly efficient, cost effective, and environmental friendly properties for the commercial applications of wastewater treatment.
        4,000원
        8.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        흰구름버섯 (Trametes hirsuta)의 균사체는 CR, CV, RBBR 등 방향족 염료가 함유된 고체와 액체 배지에서 이들 염료를 효과적으로 탈색하였으나 MB의 탈색은 저조하였다. 각각 CR, MB, CV 및 RBBR 등 4종류의 염료가 함유된 액체배지에서 흰구름버섯의 균사체를 10일 간 배양했을 때 laccase, LiP, MnP 등 세 종류의 효소를 모두 생산하였으며 이들 효소 중 laccase의 활성도가 가장 높았으며 LiP와 MnP의 활성도laccase에 비해 낮았다. 따라서 흰구름버섯 균사체에 의한 방향족 염료의 탈색에는 laccase가 주로 사용되고 LiP나 MnP는 보조적인 역할을 하는 것으로 사료된다. 또한 비스페놀 A가 0, 25, 50, 100, 200 ppm의 농도로 함유된 PDA 배지에 균사체를 접종하여 배양한 결과 비스페놀 A의 농도가 증가함에 따라 균사체의 생장은 농도 의존적으로 저해되는 것으로 나타 났다. 또한 비스페놀 A가 100 ppm 함유된 YMG 액체배지에 균사체를 접종하고 비스페놀 A의 분해율을 측정한 결과 배양 12시간 후 72.3%, 배양 24시간 후 95.3%, 그리고 배양 36시간 후에는 100% 분해된 것으로 나타났다. 따라서 본 연구 결과는 우리나라의 산업 활동 과정에서 생산되고 자연계로 배출되어 생물체에 큰 피해를 주는 합성염료와 내분비계 장애물질인 비스페놀 A를 친환경적으로 제거할 수 있는 기술의 개발에 도움이 될 수 있을 것으로 사료된다.
        4,000원
        9.
        2019.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        One- and two-dimensional carbon nanomaterials were tested as adsorbents for the elimination of two anionic dyes, reactive red 2 and methyl orange, and the cationic dye methylene blue from aqueous solutions under the same conditions. Carbon nanomaterials performed well in the removal of dyes. Surface oxygenated groups in the nanomaterials improved the cationic dyes’ adsorption, but not the adsorption of the anionic dye. The interactions between nanomaterials and dyes were verified by infrared and Raman spectroscopy. The pseudo-second order kinetic model was better fitted to the kinetic experimental data than the Elovich and pseudo-first order models. The equilibrium adsorption data were best fitted by the Langmuir model. The dimensions and morphology of the carbon nanomaterials play an important role in the adsorption of the three dyes. The main mechanism of adsorption of anionic dyes is by the interactions of the aromatic rings of the dye structures and π delocalized electrons on carbon nanostructures; the adsorption of cationic dye is mainly due to electrostatic interactions.
        4,300원
        10.
        2018.05 구독 인증기관·개인회원 무료
        Three new compounds are synthesized as color filter dyes by substituting a pyridine group into 1,4-position, 1,5-position, and 1,8-position of anthraquinone core moiety. Changes in physical properties of the synthesized compounds according to the substitution position are systematically investigated in terms of optical properties and thermal properties. The extinction coefficient value (ε) of the synthesized materials is extremely high and is above 4.22 in a log scale, and Td is above 300°C with high thermal stability.
        11.
        2015.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        구름버섯(Trametes versicolor)은 phenolic compound인 CV와 MG를 효과적으로 탈색할 수 있었으며 고체와 액체배양 상태 모두에서 CV보다 MG를 더 효과적으로 탈색시켰다. 구름버섯에 의한 두 색소의 탈색 과정에서 phenolic compounds를 분해하는 것으로 알려진 세 가지 효소 중 laccase의 활성이 가장 높았다. MnP 역시 적은 수치지만 활성을 나타냈으며 LiP의 활성은 나타나지 않았다. 따라서 구름버섯에 의한 합성염료의 분해과정에서 laccase가 주로 사용되고 MnP는 탈색과정에서 보조적인 작용을 하는 것으로 추정된다. 그러나 CV의 경우 MnP가 활발하게 염료분해에 관여하는 것으로 판단된다. 또한 MG가 대부분 탈색되었을 때의 laccase 활성(0.16 U/mg)이 CV가 대부분 탈색되었을 때의 활성(0.23 U/mg)보다 현저하게 낮은 것으로 보아 구름버섯이 CV를 탈색시키는데 더 높은 활성의 laccase가 필요로 하는 것이 밝혀졌다. 본 실험에서 한국산 구름버섯 종의 CV와 MG 탈색능력이 확인되었으며 앞으로 한국산 구름버섯을 이용한 triphenyl methane계에 속하는 합성염료의 분해에 관한 친환경적 처리기술 개발에 도움이 될 것으로 기대된다.
        4,000원
        12.
        2014.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The fabric, 100% Silk, was dyed with Atractylodes japonica extract solution. The effects of concentration of extracts (colorant), temperature of dyeing, time of dyeing and pH of dye bath were studied. As the concentration of extracts increased, color strength (K/S value) increased progressively. The K/S values increased with raising temperature, time and proper conditions were 80℃ and 80 minutes. Maximum K/S value was obtained at pH 3. The K/S values of mordanted fabrics were increased with increasing mordant concentration up to specific values. Surface color of dyed and mordanted fabrics were yellowish. Light color fastness of fabric with mordanting was fairly good 3/4 rating. The mordanted silk fabrics showed excellent antibacterial activity. The silk fabric dyed with Atractylodes japonica extract showed a superior UV protective property.
        4,000원
        13.
        2013.12 구독 인증기관 무료, 개인회원 유료
        LCD color filter용 염료로 1-amino-, 2-amino-, 1,4-diaminoanthraquinone과 methanesulfonyl chloride, benzenesulfonyl chloride를 각각 반응시켜 anthraquinonesulfonamide 화합물 1a, 1b, 2a, 2b, 3a, 3b를 합성하였다. 합성한 anthraquinonesulfonamide 화합물이 LCD color filter 용 염료로서의 적합한 특성을 갖는지 확인하기 위하여 분광특성, 용해도 특성 및 열적 안정성을 분석하였다. 분광특성으로 1a, 1b, 2a, 2b는 λmax가 395 ∼ 409 nm에서 나타나 노란색을 띄었다. 용해도 특성에서 2a와 2b는 1,4-dioxane 용매에서 3 w% 이상의 용해도를 보여 매우 우수한 결과를 나타내었다. 열적 안정성은 모든 anthraquinonesulfonamide가 200 ℃ 이상의 고온에서도 현저한 분해 없이 안정한 결과를 나타내었으며, 특히 2b와 3b는 240 ℃ 이상에서 도 중량의 95 % 이상을 유지하여 매우 우수한 열적 안정성을 보여준다.
        4,000원
        14.
        2012.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 다양한 색상의 염료가 절화 장미 ‘Akito’ 품종의 염색에 미치는 효과를 알아보기 위해 시행되었다. 12가지 색상의 염료를 이용한 염색 결과, 다채로운 색상을 구현해 내고 관상 가치를 높일 수 있었지만 절화수명은 대조구보다 1-3일 단축되었다. 4종류의 blue 염색염료를 비교한 결과 Fantasy blue (Palace Chemical Co., Japan)와 Blue No.1(Vidhi Dyestuff Mfg LTD, India)의 색상이 좋았다. 고농도 (7.5g •L-1와 10.0g •L-1)의 blue 염색의 경우 잎의 착 색이 심하고 불균일 하였으며 꽃잎의 가장자리가 짙어 지는 현상이 나타났다.
        4,000원
        15.
        2012.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was designed to evaluate to acute oral toxicity and skin irritation of Chrysanthemum dye in Sprague-Dawley (SD) rats. SD rats were orally treated with Chrysanthemum dye at a dose of 0, 1 and 2 ml/kg body weight. After oral administration, the rats were observed for 14days. In primary skin irritation test, SD rats were dermally treated with Chrysanthemum dye and observed for 3 days. To ensure the safety of Chrysanthemum dye such as the following were observed and tested. We examined the body weight, the feed intake, the clinical signs, the ophthalmological test, the histopathological test, the mortality and skin irritation. As a result, no significant differences were found in body weight, feed intake and histopathological test between control and Chrysanthemum dye treated group. In the result of skin irritation test, Chrysanthemum dye did not induce erythema and edema after topical application. Primary irritation index was “0” in the test. Therefore, it is suggested that Chrysanthemum dye has no effect on acute toxicity and side effect in SD rats and is non-irritant material based on the score “0” of primary irritation index.
        4,000원
        18.
        2010.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Removal of dyes Reactive Blue 221, N Blue RGB and Acid Blue MTR using two different samples of activated carbon by static batch method was studied. Experimental data on optical density of solutions at different concentrations ranging from 10 to 100 mg/L and of solutions after adsorption on activated carbon samples were measured. Calibration curves were plotted and the amount of dye qe adsorbed was calculated. The data was fitted to Langmuir and Freundlich isotherms for two different carbon samples and different concentration and pH values. Constants were calculated from the slope and intercept values of the isotherms. Coefficient of correlation R2 and Standard Deviation SD were also noted. The data fitted well to the isotherms. Carbon sample C1 showed higher potential to adsorb all the three dyes. Adsorption was higher at lower concentrations. Carbon sample C2 showed better adsorption in acidic pH as compared to in alkaline pH. From the analysis of the data capacity of C1 and C2 to remove the dyes from water have been compared.
        4,000원
        19.
        2010.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The study describes the results of batch experiments on the removal of Reactive Yellow 15 (RY15) and Reactive Black 5 (RB5) from synthetic textile wastewater onto Activated Carbon from Walnut shell (ACW). The experimental data were analyzed by the Langmuir, Freundlish, Temkin and Dubinin-Radushkevich (D-R) models of adsorption. The experiments were carried out as function of initial concentrations, pH, temperature (303-333), adsorbent dose and kinetics. The surface area and pore volumes of adsorbent were measured by BET and BJH methods. The findings confirm the surface area (BET) is 248.99 m2/g. The data fitted well with the Temkin and D-R isotherms for RY15 and RB5, respectively. The most favorable adsorption occurred in acidic pH. Pseudo-second order kinetic model were best in agreement with adsorption of RY15 and RB5 on ACW. The results indicate that walnut shell could be an alternative to more costly adsorbent currently being used for dyes removal.
        4,000원
        20.
        2010.08 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        In this study, activated carbon (AC) as a carbon source was modified with different concentrations of cobalt chloride (CoCl2) to prepare a Co-AC composite, and it was used for the preparation of Co-AC/TiO2 composites with titanium oxysulfate (TOS) as the titanium precursor. The physicochemical properties of the prepared Co-AC/TiO2 composites were characterized by N2 adsorption at 77 K, X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) analysis. The photocatalytic treatments of organic dyes were examined under an irradiation of visible light with different irradiation times. N2 adsorption data showed that the composites had decreased surface area compared with the pristine AC, which was 389 m2/g. From the XRD results, the Co-AC/TiO2 composites contained a mixturephase structuresof anatase and rutile, but a cobalt oxide phase was not detected in the XRD pattern. The EDX results of the Co-AC/TiO2 composites confirmed the presence of various elements, namely, C, O, Ti, and Co. Subsequently, the decomposition of methylene orange (MO, C14H14N3NaO3S) and rhodamine B (Rh.B, C28H31ClN2O3) in an aqueous solution, respectively, showed the combined effects of an adsorption effect by AC and the photo degradation effect by TiO2. Especially, the Co particles in the Co-AC/TiO2 composites could enhance the photo degradation behaviors of TiO2 under visible light.
        4,000원
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