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        검색결과 7,936

        181.
        2024.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The cost of treating water purification plant water treatment residuals is high, with a low recovery rate and unstable effluent water quality, particularly in plants using lake and reservoir water sources in severe cold regions. Maximizing water resource utilization requires integrating water treatment residuals concentration and treatment effectively. Here, ceramic membrane technology was employed to separate supernatant and substrate after pretreatment. Optimal settling was achieved using 75 μm magnetic powder at 200 and 4 mg/L of nonionic polyacrylamide co-injection. Approximately 65% of the separated supernatant was processed by 0.1–0.2 μm Al2O3 ceramic membranes, yielding a membrane flux of 50 L/m2h and a water recovery rate of 99.8%. This resulted in removal rates of 99.3% for turbidity, 98.2% for color, and 87.7% for color and permanganate index (chemical oxygen demand, COD). Furthermore, 35% of the separated substrate underwent treatment with 0.1–0.2 μm mixed ceramic membranes of Al2O3 and SiC, achieving a membrane flux of 40 L/m2h and a water recovery rate of 73.8%. The removal rates for turbidity, color, and COD were 99.9%, 99.9%, and 82%, respectively. Overall, this process enables comprehensive concentration and treatment integration, achieving a water recovery rate of 90.7% with safe and stable effluent water quality.
        4,300원
        182.
        2024.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Graphene-based solar cells and supercapacitors integrated into photosupercapacitors represent a pioneering advancement. These devices leverage the exceptional properties of graphene, such as high conductivity and large surface area, to enhance both solar energy conversion and energy storage. The integration of these technologies into photosupercapacitors creates a multifunctional device capable of harnessing solar energy and storing it efficiently. This innovative approach holds promise for sustainable and versatile energy solutions, marking a significant step towards developing efficient and compact energy storage systems. This integration addresses the intermittent nature of solar power generation by providing a continuous and reliable power supply through energy storage. Supercapacitors are one such energy device with a high-power density and excellent specific capacitance which is integrated will a dye-sensitized solar cell (DSSC) comprising a single system of photosupercapacitor. A novel electrode material of NiO/CuO/Co3O4/rGO was synthesized which serves as the Pt-free counter electrode of DSSC and working or storage electrode of supercapacitor later was used as the intermediate electrode and storage electrode of a photosupercapacitor. The integrated photosupercapacitor device had a photovoltage of 0.81 V with arealspecific capacitance, energy and power density of 190.12 mF cm− 2, 17.325 μW h cm− 2 and 0.162 mW cm− 2, respectively. The device self-discharged in 385 s with an overall conversion efficiency of 2.17%, resulting in a self-charged energy device.
        4,200원
        183.
        2024.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Gold nanoparticles (Au NPs) decorated carbon nanofibers (CNFs) have been prepared by an electrospinning approach and then carbonized. The prepared Au-CNFs were employed to modifying a screen printed electrode (SPE) for simultaneous determination of ascorbic acid (AA), dopamine (DA) and uric acid (UA). Au NPs are uniformly dispersed on carbon nanofibers were confirmed by the structure and morphological studies. The modified electrodes were tested in cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry (CA) to characterize their electrochemical responses. Compared to bare SPE, the Au-CNFs/SPE had a better sensing response to AA, DA, and UA. The electrochemical oxidation signal of AA, DA and UA are well separated into three distinct peaks with peak potential separation of 280 mV, 159 mV and 439 mV between AA-DA, DA-UA and AA-UA respectively in CV studies and the corresponding peak potential separation in DPV studies are 290 mV, 166 mV and 456 mV. The Au-CNFs/SPE has a wide linear response of AA, DA and UA in DPV analysis over the range of 5–40 μM ( R2 = 0.9984), 2–16 μM ( R2 = 0.9962) and 2–16 μM ( R2 = 0.9983) with corresponding detection limits of 0.9 μM, 0.4 μM and 0.3 μM at S/N = 3, respectively. The developed modified SPE based sensor exhibits excellent reproducibility, stability, and repeatability. The excellent sensing response of Au-CNFs could reveal to a promising approach in electrochemical sensor.
        5,100원
        184.
        2024.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Graphitic nitrogen-doped carbon film/nanoparticle composite, in which the films were wrapped and separated by the nanoparticles, was prepared through a simple co-calcination route. Due to its unique porous structure and improved nitrogen content, the as-prepared electrode material could exhibit high specific capacitances of 317.5 F g− 1 at 0.5 A g− 1 and 200.0 F g− 1 at 20 A g− 1, and stable cycling behavior with no capacitance decline after 10,000 cycles in three-electrode system. When assembled in two-electrode capacitor, its specific capacitance could be well kept at 265.5 F g− 1 at 0.5 A g− 1, and thus the supercapacitor with a high energy density of 9.22 Wh kg− 1 was obtained. The superior energy storage properties of the as-prepared material indicate its promising application as high-performance carbon-based electrode for supercapacitors.
        4,300원
        185.
        2024.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In recent years, the search on fabrication of highly efficient, stable, and cost-effective alternative to Pt for the hydrogen evolution reaction (HER) has led to the development of new catalysts. In this study, we investigated the electrocatalytic HER activity of the Toray carbon substrate by creating defect sites in its graphitic layer through ultrasonication and anodization process. A series of Toray carbon substrates with active sites are prepared by modifying its surface through ultrasonication, anodization, and ultrasonication followed by anodization procedures at different time periods. The anodization process significantly enhances the surface wettability, consequently resulting in a substantial increase in proton flux at the reaction sites. As an implication, the overpotential for HER is notably reduced for the Toray carbon (TC-3U-10A), subjected to 3 min of ultrasonification followed by 10 min of anodization, which exhibits a significantly lower Tafel slope value of 60 mV/dec. Furthermore, the reactivity of the anodized surface for HER is significantly elevated, especially at higher concentrations of sulfuric acid, owing to the enhanced wettability of the substrate. The lowest Tafel slope value recorded in this study stands at 60 mV/dec underscoring the substantial improvements achieved in catalytic efficiency of the defect-rich carbon materials. These findings hold promise for the advancement of electrocatalytic applications of carbon materials and may have significant implications for various technological and industrial processes.
        4,000원
        186.
        2024.11 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Nanoparticles, especially those derived from plant extracts, are becoming increasingly popular as a bio-based, environmentally friendly alternative to conventional technologies. The Maui rose, a flowering plant with medicinal and therapeutic properties, is one of the most important of these materials because its extract component has antibacterial, antioxidant and anti-inflammatory biological activity. In this work, we report on synthesizing and characterizing iron oxide nanoparticles (Fe2O3) extracted from flower plants (Borago), to create persistent and environmentally friendly antibacterial agents. As part of the chemical formation process, Fe2O3 nanoparticles were extracted from specific flower plants utilizing a series of carefully regulated chemical reactions. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and atomic force microscopy (AFM) of the samples were studied. The nanoparticles produced were analyzed using common microbiological methods and studies (EDS). The antibacterial activity of the Fe2O3 nanoparticles and their effect on a range of microorganisms were evaluated. The results demonstrated that Fe2O3 nanoparticles were successfully synthesized with a specific crystal structure and good anti-bacterial activities.
        4,000원
        187.
        2024.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        During the period of 1959 to 1984, North Korean false propaganda led over 90,000 ethnic Koreans and their families to migrate from Japan to North Korea. Once in North Korea, the migrants suffered severe discrimination and human rights abuses. For decades, there was little prospect of justice for these abuses. In recent years, however, survivors of this migration who escaped North Korea have renewed efforts to gain some type of recognition and compensation. This note reviews three of these attempts: lawsuits in Japanese and South Korean courts, as well as a petition that was brought before the Korean Truth and Reconciliation Commission. While each of these avenues has helped bring to light the truth of North Korean deception, more work remains to be done with respect to collecting compensation.
        4,000원
        188.
        2024.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        More than 5 billion people will use the Internet and social media by the end of 2024 and global influencer marketers reached USD 24 billion in early 2024. A regulation is thus needed to protect domestic consumers from the negative effects of global influencer marketing, such as deception, hidden advertising, and information uncertainty. Can the current legal framework effectively protect domestic consumers from misleading or deceptive and illegal advertising conducted by influencers through social media platforms from outside of their jurisdiction This essay first examines social influencing and explains how social influencers operate across national borders. It then discusses domestic legislation governing social influencers in China, Japan and South Korea and discusses why these domestic frameworks provide scant protection for consumers against false advertising and misinformation originating in another country. Finally, this essay proposes an international solution to a problem that will only increase size and severity in the future.
        4,900원
        189.
        2024.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Under Trump and Biden, the US trade policy has veered away from its traditional approach, developed since World War II, from multilateralism to focusing primarily on national and unilateral concerns. At the center of this approach have been tensions with China. This includes a renewal of industrial policies, protectionism and, most importantly, reliance on national security, manifested by newer and unexpected geopolitical developments. The discussion of trade policy today has become very toxic, especially during this presidential campaign season, with its renewed focus on tariffs. The trade debate in the US is now entering a new stage with the nomination of Kamala Harris and J.D. Vance. I believe the US drift away from the postwar policies of promoting global trade and investment will continue. Nationalist and protectionist policies will continue as part of a new economic and industrial policy, fused with national security concerns and rhetoric, no matter who wins.
        4,900원
        190.
        2024.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The ongoing conflict in Gaza strip has resulted in significant humanitarian crisis, with civilians often bearing the brunt of violence. This article critically examines the role of IHL in the protection of civilians affected by the armed conflict. The study focuses on key IHL principles, including distinction, proportionality, and precaution, and assesses their application by the parties involved. It employs an analytical and descriptive research methodology. The findings reveal that both Israel and Hamas have committed numerous violations of IHL, including indiscriminate attacks and failure to protect civilian populations. Despite the clear legal frameworks set by IHL, the lack of accountability and enforcement has hindered its effectiveness. The author concludes that while IHL provides a robust legal framework for civilian protection, the political complexities of the Israel-Hamas conflict severely limit its implementation, leaving civilians vulnerable. The research calls for stronger international mechanisms to ensure compliance with IHL and improve civilian protection in the region.
        4,600원
        191.
        2024.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Following the attack on Israel by Hamas militants on October 7, 2023, Israel declared war on the Gaza Strip. In the relentless and nonstop bombardment of the Gaza Strip, about 40,000 Palestinian civilians have lost their lives, the majority of whom were children and women. Additionally, more than 92,000 Palestinians have been injured and many more are still missing or under the rubble. The dire situation in the Gaza Strip requires a firm stand from the international community, as what is happening to the Palestinian people is nothing short of genocide. This paper discusses Israel’s attacks on the Gaza Strip and illustrates how these actions meet the criteria for war crimes, crimes against humanity, and genocide. It also discusses the case filed by South Africa against Israel in the International Court of Justice, alleging that Israel has violated the Convention on the Prevention and Punishment of the Crime of Genocide.
        6,100원
        192.
        2024.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Regional economic integration organizations (REIOs) can ratify climate change agreements as mixed agreements, including the Paris Agreement, with their member states. A question may arise on what responsibilities can REIOs have under the Paris Agreement in relation to the member states. Analyzing the draft articles on the responsibility of international organizations reveals that REIO can have derived (indirect) responsibility for non-fulfilling the obligations by member states due to the normative control resulting from the adoption of binding resolutions. Also, under Article 4.18 of the Paris Agreement, REIO will be jointly responsible for non-realization of the goals communicated in the NDCs together with non-compliant member. This will make the non-compliant states responsible externally to the third parties and to REIO internally in achieving the goals of NDC and will encourage the compliant member states to participate in realizing the collective goal of REIO because of influence of not realizing the collective goal.
        5,800원
        193.
        2024.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        사막화는 기후변화로 인해 전 세계적으로 심화되고 있으며, 몽골도 이에 큰 영향을 받고 있다. 본 연구는 한국기독교환경운동연대(KCEMS)가 시작한 “은총의 숲” 프로젝트를 탐구함으로, 몽골의 사막화 문제를 다룬다. 30년에 걸친 이 프로젝트는 사막화 방지, 지속 가능한 창조 보전, 다차원적 인 이웃 사랑을 실천하는 한국교회의 생태적 선교 사례이다. KCEMS는 이 프로젝트를 지속적으로 추진하고 모니터링하며, 창조질서 보전 차원에 서 몽골 현지인들에게 실질적인 경제적 혜택을 제공함으로 몽골 현지인들의 참여를 촉진한다. 따라서 변혁적 제자도의 관점에서, 이 프로젝트는 기후변 화로 인해 영향을 받고 고통받는 이들과의 선교적 연대를 구현한다. 이를 통해 본 연구는 교회가 화해의 메시지를 전파하고, 생명죽임의 세력에는 저항하고 성령님과 연합하여 생명살림의 희망을 창조하도록 강조하며, 교회가 사랑과 정의의 복음을 선포하는 예언자적 사명으로서의 사역을 강화할 것을 촉구한다.
        7,000원
        194.
        2024.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Parallel importation of patented products, “first sale doctrine,” is an effective and efficient way of handling the importation of patent-protected goods. The national exhaustion idea is being used in Pakistan regarding patent exhaustion. Market competition and lower pricing phenomena are affected by this strategy. Case studies from the European Union (EU), the United States (US) and China are used to show how businesses can protect consumers’ rights by parallel imports. The US and China follow international exhaustion whereas the EU follows the regional exhaustion principle, which is comparable with Pakistan concerning the Shanghai Cooperation Organization (SCO). By finding lower-priced products, promoting international economic integration and regional collaboration with SCO, Pakistan can avail better investment opportunities. Case studies show result-oriented efforts regarding the implementation of the international parallel exhaustion strategy. Study recommends raising awareness and enhancing legal clarity, IP protection, and stakeholder input to ensure compliance with an international exhaustion system.
        5,200원
        195.
        2024.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        이 연구에서는 카자흐스탄의 난민 관련 법제와 1951년 난민협약 및 의정서 의 준수와 관련된 문제점을 살펴보고자 한다. 현재 카자흐스탄은 난민 수용을 많이 하는 여러 국가들과 달리 난민 및 망명 신청자 문제를 다루기 위한 포괄 적인 법제가 부재한 상황이다. 카자흐스탄은 1990년대 후반에 난민협약 및 관 련 국제 조약을 비준하였음에도 불구하고, 국내 이행을 위한 법안을 2009년이 되어서야 통과시켰다. 이 과정에서 카자흐스탄의 자결권 행사와 국제인권법 준 수 간에 대립된 바가 있다. 또한 지나치게 정치화된 시스템은 인도주의 법 준 수보다 정치적 의제를 우선시하여 국제적 의무를 이행하지 못한다는 비판도 제 기되고 있다. 이러한 배경하에 이 연구에서는 카자흐스탄의 난민, 망명 신청자, 무국적자의 법적 지위에 관한 몇 가지 문제점을 지적한다. 첫째, 1951년 난민 협약과 이를 이행하기 위한 국내 난민법 간에 많은 차이가 있으며, 대표적으로 강제송환금지의 원칙이 준수되지 않는다는 점이다. 둘째, 망명 신청자를 위한 ‘보충적 보호’에 관한 조항이 포함되어 있지 않다. 셋째, 카자흐스탄에서 난민 지위는 1년 동안만 부여되는 반면 인근 중앙아시아 국가들은 보다 더 긴 기간 을 허용한다는 점에서 비교된다. 넷째, 무국적자에 대한 행정 절차상 문제가 제기된다. 특히, 국제협약에 부합하는 입법 조치를 통해 무국적자를 판단하기 위한 구체적인 절차가 확립되어 있지 않다. 마지막으로, 망명 신청자가 망명 신청에 대한 결정이 내려지기 전에 강제로 송환된 사례가 있는데 이것은 명백 한 국제법 위반 해당된다. 아울러 해상에서 난민 및 망명 신청자를 송환하는 경우 강제송환금지의 원 칙을 해상 국경에 접한 공해상에서도 적용할 수 있다. 카스피해는 카자흐스탄 을 포함한 5개국을 둘러싼 중앙아시아 최대 내해이며 이 지역의 해상난민을 차 단하는 유일한 경로이다. 난민 이동과 관련된 독특한 지리적 특징에 가지고 있 으나 육상과 항공으로 국경을 넘어오는 것이 우세하기 때문에 카스피해를 너머 로 피난처를 찾는 것은 사실상 실효성이 없다. 최근 유라시아 국가들의 대규모 이주 흐름으로 인해 많은 난민과 망명 신청 자들이 카자흐스탄에 망명을 꾀할 것으로 예상된다. 따라서 카자흐스탄 정부는 난민 보호를 위해 난민에 대한 국내법을 개정하여 국제 의무를 가장 효과적으 로 준수할 필요성이 있다.
        9,200원
        198.
        2024.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The feeder pipes of the primary cooling system in a pressurized heavy water reactor (PHWR) are composed of carbon steel SA 106 GR.B. On the surface of this structural material, corrosion oxide layers including radionuclides are formed due to the presence of active species from water decomposition products caused by radiation, as well as the high temperature and high-pressure environment. These oxide layers decrease the heat transfer efficiency of the primary cooling system and pose a risk of radiation exposure to workers and the environment during maintenance and decommissioning, making effective decontamination essential. In this study, we simulated the formation of the corrosion oxide layer on the surface of carbon steel SA 106 GR.B, characterized the formed corrosion oxide layer, and investigated the dissolution characteristics of the corrosion oxide layer using oxalic acid (OA), a commercial chemical decontamination agent. The corrosion oxide layer formed has a thickness of approximately 4 μm and consists of hematite ( Fe2O3) and magnetite ( Fe3O4). The carbon steel coupons with formed oxide layers were dissolved in 10 mM and 20 mM OA solutions, resulting in iron ion concentrations of 220 ppm and 276 ppm in the OA respectively. In 10 mM and 20 mM OA, the corrosion depths of the coupons were 8.93 μm and 10.22 μm, with corrosion rates of 0.39 mg/cm2·h and 0.45 mg/cm2·h, respectively. Thus, this demonstrates that higher OA concentrations lead to increased dissolution and corrosion of steel.
        4,000원
        199.
        2024.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Carbon quantum dots (CQDs) are novel nanocarbon materials and widely used nanoparticles. They have gradually gained popularity in various fields due to their abundance, inexpensive cost, small size, ease of engineering, and distinct properties. To determine the antibacterial activity of metal-doped CQDs (metal-CQDs) containing Fe, Zn, Mn, Ni, and Co, we chose Staphylococcus aureus as a representative Gram-positive strain and Escherichia coli as a representative Gram-negative bacterial strain. Paper disc diffusion tests were conducted for the qualitative results, and a cell growth curve was drawn for quantitative results. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and IC50 were measured from cell growth curves. As a result, all of the metal-CQDs showed toxicity against both Gram-positive and Gram-negative bacteria. Furthermore, Gram-negative bacteria was vulnerable to metal-CQDs than Gram-positive bacteria. The toxicity differed concerning the type of metal-CQDs; Mn-CQDs exhibited the highest efficacy. Hence, this study suggested that CQDs can be used as new nanoparticles for antibiotics.
        4,200원
        200.
        2024.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this work, the depth of the interphase in graphene polymer systems is determined by the properties of graphene and interfacial parameters. Furthermore, the actual volume fraction and percolation onset of the nanosheets are characterized by the actual inverse aspect ratio, interphase depth, and tunneling distance. In addition, the dimensions of graphene, along with interfacial/interphase properties and tunneling characteristics, are utilized to develop the power-law equation for the conductivity of graphene-filled composites. Using the derived equations, the interphase depth, percolation onset, and nanocomposite conductivity are graphed against various ranges of the aforementioned factors. Moreover, numerous experimental data points for percolation onset and conductivity are presented to validate the equations. The optimal levels for interphase depth, percolation onset, and conductivity are achieved through high interfacial conductivity and large graphene nanosheets. In addition, increased nanocomposite conductivity can be attained with thinner nanosheets, a larger tunneling distance, and a thicker interphase. The calculations highlight the considerable impacts of interfacial/interphase factors and tunneling distance on the percolation onset. The highest nanocomposite conductivity of 0.008 S/m is acquired by the highest interfacial conduction of 900 S/m and graphene length (D) of 5 μm, while an insulated sample is observed at D < 1.2 μm. Therefore, higher interfacial conduction and larger nanosheets cause the higher nanocomposite conductivity, but the short nanosheets cannot promote the conductivity.
        4,200원