Coal tar pitch is a raw material that can be made from various carbon materials such as activated carbon, carbon fiber, and artificial graphite through heat treatment. In particular, it is an important raw material used as a binder and impregnated pitch when manufacturing carbon composite materials. In order to improve the physical properties of such a carbon composite material, the content of β-resin is an important factor. Although β-resin plays the role of a binder, it also corresponds to fixed carbon, so it can determine the physical properties after carbonization. In this study, we compared the physical properties of coal tar pitch various temperature ramping rate, and found through Py-GC/MS analysis that intermediate materials were generated by heteroatoms such as oxygen and nitrogen. MALDI-TOF/MS analysis revealed that these intermediate materials overlapped with the molecular weight region of β-resin. Therefore, the content of β-resin is in the following order: 430–5 (12.8 wt%), 430–10 (10.2 wt%), and 430–2 (6.3 wt%), and when 430–5 is used as a binder, the highest density appeared at 1.75 g/cm3. However, such intermediate materials undergo thermal decomposition even at temperatures above 900 °C. As a result, after carbonization, 430–5 had a density of 1.60 g/cm3, which was similar or lower than that of 430–2 (1.72 → 1.63 g/ cm3) and 430–10 (1.73 → 1.61 g/cm3). From these results, it is expected that if the heteroatom content is distributed in an appropriate amount and the heating rate is well controlled, it will be possible to maintain a high density even after carbonization while ensuring a high beta-resin content.
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.
Complex structure constituting of several layers of heteroatom-doped N-CDs are used as a main sensing film along with aluminum electrodes in conductometric gas sensing system for sensitive and selective monitoring of CO2 and CO gases diluted with normal air, which are extensively prevalent in the atmosphere primarily due to the industrial revolution, locomotives, and numerous natural phenomena’s and the limit of detection (LOD) turned out to be 400 ppm and 30 ppm, respectively, with 20% relative humidity at 30 °C and pressure 1 (atm) which are good for healthy air quality checks. The sensor performance was satisfactory and bidirectional at ambient room temperature (30 °C) and pressure (1 atm) conditions but the relative humidity (50%) at 30 °C had a detrimental impact on the sensing responses, therefore intermittent heating at 80 °C for several minutes between the sensing responses was provided to the sensing chip or one should use gas filter membranes to block humidity, thereby maintaining its constant performance with great ease and accuracy. The cyclic voltammetry revealed well-defined oxidation and reduction peaks, with excellent stability and reversibility. In a nutshell, heteroatom-doped N-CDs’ nanocomposite material can revolutionize in a better environmental pollution monitoring by sensing gases in an extensively lesser response and recovery times.
Silicon carbide (β-SiC) was synthesized through an improved sol–gel method, then Ni/SiC catalysts were prepared using a hydrothermal method. The catalysts were characterized using TEM, H2- TPR, CO2- TPD and N2- TPD, etc. The results showed that the synthesized β-SiC had a large specific surface area, promoting the dispersion of Ni species and thus exposing more active sites. The interaction between Ni species and β-SiC contributed significantly to catalytic performance. Furthermore, the strong alkalinity of catalyst could adjust the bond energy of the active metal and N (M–N), which were conducive to desorption of the recombinant N2 from the metal surface, promoting to ammonia decomposition. Among the Ni/SiC catalysts, 30Ni/SiC-700 synthesized with the Ni loading of 30 wt% and calcination temperature of 700 °C, exhibited the optimal ammonia conversion rate of 93.4% at 600 °C under the space speed of 30,000 mL∙gcat −1∙h−1, and demonstrated a long-term stability, suggesting a very promising catalyst in ammonia decomposition.
With the continuing advances in technology, electrical energy storage has become increasingly important. Among storage devices supercapacitors’ distinct qualities, such as a long lifespan, quick charge/discharge speeds, and high-power density, make them viable substitutes for traditional batteries. In this study a simple hydrothermal method was used to synthesize a h-MoO3/graphene oxide (GO) composite for such applications. The crystal structure, morphology, and chemical bonding were characterized using X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and Raman spectroscopy. XRD confirmed the hexagonal crystal structure, and no changes were observed after GO incorporation. The FESEM images revealed that the nanosheets of GO and hexagonal rods MoO3 were well coupled with the GO sheets. The electrochemical properties of the pure h-MoO3 and h-MoO3/GO composites were studied using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). The nanocomposite electrode demonstrated a specific capacitance of 134 Fg-1 at a current density of 3 mA/cm-2, an energy density of 26.8 Wh/kg-1, and power density of 560 W/kg-1 in an aqueous acidic electrolyte 1 M H2SO4, which is notably higher than that of pure MoO3. This indicates the promising electrochemical performance of MoO3/GO composite for supercapacitor applications. The enhanced capacitive performance may have resulted from the decrease in the charge transfer resistance (Rct), calculated from the Nyquist plot. Furthermore, the composite material exhibited stability and a capacitive retention of 76 % after 1,000 cycles. This confirms the benefits of incorporating GO to enhance material retention for better long-term results. The results of this study demonstrate its potential to advance energy storage technology. Maintaining the hexagonal crystal structure of h-MoO3 while incorporating GO improves the composite’s structural stability, an important factor for reliable long-term use. Moreover, the observed reduction in crystallite size due to the presence of GO suggests improved electrochemical performance.
Magnons have unique properties, including long propagation length, and can exist in insulators. Magnon valve structures, which consist of two magnetic insulating layers, offer a promising approach for advanced magnetoresistive randomaccess memory (MRAM) technology and an alternative to the limitations of traditional electronic devices. In this study, we investigate a magnon valve structure that incorporates a platinum (Pt) spacer between two magnetic insulator layers, specifically yttrium iron garnet (Y3Fe5O12, YIG). Structural characterization of the YIG/Pt/YIG magnon valve was carried out using X-ray diffraction (XRD) and transmission electron microscopy (TEM), confirming the high-quality growth of the multilayer structure. The magnon valve behavior was assessed through vibrating sample magnetometry (VSM) and spin Seebeck effect (SSE) measurements. Our results demonstrate magnon valve behavior, which becomes apparent as the Pt spacer reaches a thickness sufficient to decouple the magnetization of the YIG layers. The magnon valve ratio of the magnon valve can be modulated, and clarity of the those states can be enhanced.
This study investigates the development of risedronate (RSD)-incorporated polycaprolactone (PCL)/chitosan composite films for potential use in drug delivery systems aimed at bone repair. PCL and chitosan were blended in varying ratios (25 %, 50 %, 75 % PCL), and their miscibility, morphology, and hydrophilicity were analyzed. The effects of incorporating RSD at different concentrations (10-7 to 10-4 M) on MG63 preosteoblast cell proliferation and differentiation were also evaluated. The results demonstrated that blending of the hydrophobic PCL with hydrophilic chitosan was challenging, due to poor miscibility and phase separation. Optimal blending conditions and drying temperatures were essential for homogeneous film formation. The incorporation of RSD influenced cellular behavior, with 50 % PCL showing the most effective cell proliferation and moderate hydrophilicity. However, higher RSD concentrations (10-4 M) inhibited proliferation, while lower concentrations (10-7 M) promoted it. RSD also enhanced osteoblast differentiation, as evidenced by increased alkaline phosphatase (ALP) activity, particularly in 75 % PCL films. These findings suggest that adjusting the PCL/chitosan ratio and RSD concentration can optimize drug release and cellular responses, making this composite system a promising candidate for bone tissue engineering applications.
This study investigates the performance characteristics of electrodeposited (ED) silver nanowires (AgNWs) networks as transparent conducting electrodes (TCEs) considering Cu(In,Ga)Se2 (CIGS) thin-film solar cells. The electrodeposition process uniformly deposits silver onto a network of spin-coated AgNWs, resulting in the enlargement of individual nanowire diameters and the formation of stronger interconnections between the AgNWs. This structural enhancement significantly improves both the electrical conductivity and thermal stability of the ED AgNW networks, making them more efficient and robust for practical applications in solar cells. The study comprehensively examines the optoelectronic properties of the ED AgNW networks, encompassing total and specular transmittance, transmission haze values, and sheet resistance, with varying durations of silver electrodeposition. Additionally, this study presents the current density (J)-voltage (V) characteristics of CIGS thin-film solar cells employing the ED AgNW TCEs, revealing how electrodeposition duration impacts overall device performance. These findings offer valuable insights for optimizing TCEs in not only thin-film solar cells but also in other optoelectronic devices, highlighting the potential for improved long-term stability across various applications without compromising performance.
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.
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.
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.
The increase in space activity has contributed to a convergence of cybersecurity and outer space at a critical moment in the digital era requiring a thorough examination of the threats to space-based assets and the protective measures required. As satellites and space technology become integral to global operations, their сyber security is parаmount given their vulnerability to cyber espionage, interference and attacks. This paer highlights the significance of technological advancements and their dual role in improving space systems while also introducing new vulnerabilities. It explores varied national cybersecurity practices focusing on space stakeholders such as the US, the EU, China, Russia and UAE, revealing the global strategies employed against cyber threats. Moreover, the importance of laws and regulations such as the Outer Space Treaty in countering cyber attacks and emphasising the need for agile legal frameworks to address cybersecurity challenges in outer space is also examined. Moreover, the paper addresses complex issues of cybersecurity in outer space, particularly innоvation, collaboration and legal reforms.
The death penalty is a controversial topic due to its implications for human rights, particularly the right to life, considered a fundamental right. Some argue that the death penalty violates this right, while others believe it is a form of justice for severe crimes. This research explores the debate between the death penalty and human rights using a normative, juridical method and literature review. Some countries still practice the death penalty, while others have abolished it, citing concerns about justice and fairness. The criminal justice system often exhibits disparities, with marginalized groups facing higher rates of execution than wealthier or majority individuals. These inequalities challenge the principle of equality before the law and the integrity of justice. Efforts to reform include restricting or abolishing the death penalty due to concerns about law enforcement abuse, judicial errors, and ineffectiveness in deterring crime. The debate over its place in justice systems remains ongoing.
According to the recently revised seismic design standards, seismic design of underground structures is required. Concrete underground outer walls are installed separately from temporary earth retaining walls as permanent underground outer walls. This raises issues of constructability, economy, and space narrowness. Therefore, a steel underground continuous wall is developed to promote construction efficiency, safety, and economy by introducing the off-site construction (OSC) method of underground structures. The steel underground continuous wall will be used as a permanent underground continuous wall along with the temporary earth retaining wall. To this end, it must satisfy structural performance equivalent to or higher than the concrete underground outer wall. The integrity and in-plane shear resistance performance between single panel members must be satisfied to be used as a permanent wall. The interlocking effect through geometric bonding is intended to enhance the bonding effect between these members. Therefore, trapezoidal members were developed, and bending performance tests and analyses of each member were performed to confirm the structural bending performance of these members. The bending performance improvement effect of the combined multiple members was confirmed. As a result, it was confirmed that the integration of members and structural performance was improved due to the interlocking effect of the absence of joints. The seismic design analysis of the demonstration site was performed with these developed members, and it was confirmed that the structural performance was equivalent to or higher than that of the existing RC underground continuous wall. As a result, it was confirmed that the steel underground continuous wall can be used as a permanent underground wall together with the temporary earth retaining wall.
This study emphasizes the vital role of local governments in Vietnam in advancing gender equality, particularly in achieving the UN Sustainable Development Goal (SDG) 5. It argues that local governance is crucial for translating national gender equality commitments into practical outcomes while simultaneously driving sustainable development. This article examines Vietnam’s legal frameworks, policies, and local governance practices to assess their effectiveness in promoting gender-responsive governance under the UN SDG framework. The author explores the relationship between local governance and gender equality, emphasizing the transformative impact of integrating gender perspectives at the local level. The findings demonstrate a strong link between effective local governance and progress toward SDG 5. She advocates for empowering local governments to implement gender-inclusive policies, which are essential for achieving gender equality and sustainable development in Vietnam. Furthermore, it provides strategic recommendations to strengthen gender responsiveness in local governance, contributing to the broader discourse on sustainable and inclusive development.
This research examines China’s development in terms of the nation’s SOE reforms surrounding the two major milestones in China’s integration with neoliberalism, the accession to the World Trade Organization and the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP). It considers the interlinking of the legal aspect of China’s SOEs reform with its economic development, and reinforces the economic argument that China has embraced both neoliberalism and state-capitalism in order to achieve its industrial development. This paper highlights the persistent logic of China’s SOEs reform which aims to approach international legal standards while keeping sight of the objectives of economic development. China’s semi-embrace of neoliberalism and its insistence on state capitalism, on the one hand, provide an alternative developmental model for other developing countries, while on the other hand, facing an increasingly deteriorating relationship with the US which cannot tolerate any rising power that challenges its hegemony, especially a power with a different ideology.
Online infringement of Artificial intelligence (AI) generated content essentially constitutes IP infringement and should adhere to Article 50 of Law of the People’s Republic of China on the Law Applicable to Foreign-Related Civil Relationships. However, applying Article 50 to online infringement involving AI-generated objects presents a dual interpretation dilemma. The first dilemma pertains to the interpretation of the requested place of protection. The second issue concerns the redundancy of party autonomy in the article. Therefore, Article 50 should be reinterpreted with as emphasis on maintaining the territoriality of IP rights to make it applicable to online infringement of AI-generated objects. The place where protection is sought should be understood as the forum. If there are relevant factors, the affected cyberspace can be ‘collapsed’ into the court’s location. By employing the territoriality of IP, party autonomy should be limited to regulating the issue of damages.
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.
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.
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.