Likely impact of Antarctic sea ice loss on shifting sociocultural values

In 2023, Antarctic sea ice declined to historically low levels, prompting researchers to use CMIP6 climate models to assess the event’s rarity and connection to climate change

China's Angel Investment Policy

Purpose: This paper summarized and systematized the case of China's policies applied to attract angel investment which turned this country into a global highlight in angel investment.   Theoretical framework: The authors conducted a literature review on start-up and angel investment to introduce angel investment in China, analyze the role of angel investments in developing start-ups, and factor determinants and policy of angel investment in China.   Design/Methodology/Approach: This paper uses qualitative method to provide overviews on the case of China in attracting angel investment for their start-ups with an updated analysis on their relevant factor determinants and policies that contributed to the success of China.   Findings: It is found that the Chinese Government has actively carried out packages, including tax incentives, built programs, investment cooperation funds, developed networks, and angel investment education systems to boost funding readiness for firms. They also focus on promoting the start-up ecosystem and providing financial support to implement an innovation-driven development strategy to raise the nation's competitiveness.   Research, practical & social implications: This paper provides some suggestions for Chinese government in making policies to enhance the role of angel investments in developing start-ups.   Originality/Value: This paper contributes to the evolvement of research about start- up and angel investment, particularly in China, in the context of high-tech  production and breakthrough technologies, by providing a policy perspective to imply lessons for other countries

The Efficiency and the Performance of the Logistics Global Supply Chain Activities to Vietnam Exportation: an Empirical Case Study

Purpose: This research paper aims to determine the factors affecting the efficiency and logistics performance index (LPI) of Vietnam's exports to foreign partners during 2018-2022 are due to the impact of the COVID-19 pandemic.   Theoretical Framework: Based on the primary factors affecting the efficiency and performance of global supply chain activities in logistics for Vietnam's exports, including practical impact and logistics results of enterprises in Vietnam. Based on the primary factors affecting the efficiency and performance of global supply chain activities in logistics for Vietnam's exports, including (1). Customs efficiency (speed, simplicity and predictability of customs clearance procedures) (2). Quality of infrastructure related to trade and transport, including Roads, railways, ports, airports, warehouses and information technology ...(3). The level of ease when arranging to transport import and export goods with competitive prices (costs such as warehousing fees, port fees, tolls ... ) (4). Capacity and quality of logistics service providers ... (5). Ability to track and trace shipments. (6). Timeliness of the shipment to the destination within the specified time limit. The practical impact and logistics results of enterprises in Vietnam.   Method: The panel approach allows the authors to explore the heterogeneity in data across countries. Fixed effects (FE) and random effects (RE) models were used to estimate the model. Then, the Hausman test is carried out to decide which model is appropriate. The data were collected from 240 observations from Vietnam and 80 major export partner countries of Vietnam.   Findings: The research results show that the cost, time and capacity of providing logistics services have the most significant impact on Vietnam's exports.   Practical & social implications: Overall, to increase the efficiency and logistics efficiency of enterprises. The Vietnamese Government needs to cooperate and propose ideas to partner countries to improve logistics activities for exports from Vietnam. Logistics is beginning to play an increasingly important role in the competitiveness of economies.   Originality values: This study also confirms the sustainability of the extended gravity model using OLS and RE methods by substituting different variables for the country's logistics efficiency and solving the endogenous problem in the model while applying the regression method to industrial variables. We find that an 1% improvement in Vietnam's logistics would increase Vietnam's exports by 1.443%, and an 1% improvement in a partner country’s performance would help promote Vietnam's exports to this country by 0.546%

Simple thermal-electrical model of photovoltaic panels with cooler-integrated sun tracker

This paper presents a simple thermal-electrical model of a photovoltaic panel with a cooler-integrated sun tracker. Based on the model and obtained weather data, we analyzed the improved overall efficiency in a year as well as the performance in each typical weather case for photovoltaic panels with fixed-tilt systems with a tilt angle equal to latitude, fixed-tilt systems with cooler, a single-axis sun tracker, and a cooler-integrated single-axis sun tracker. The results show that on a sunny summer day with few clouds, the performance of the photovoltaic panels with the proposed system improved and reached 32.76% compared with the fixed-tilt systems. On a sunny day with clouds in the wet, rainy season, because of the low air temperature and the high wind speed, the photovoltaic panel temperature was lower than the cooler’s initial set temperature; the performance of the photovoltaic panel with the proposed system improved by 12.55% compared with the fixed-tilt system. Simulation results show that, over one year, the overall efficiency of the proposed system markedly improved by 16.35, 13.03, and 3.68% compared with the photovoltaic panel with the fixed-tilt system, the cooler, and the single-axis sun tracker, respectively. The simulation results can serve as a premise for future experimental models

Facile Synthesis of Carbon Quantum Dots by Plasma-liquid Interaction Method

Carbon quantum dots (CQDs) are a novel type of fluorescent nano-materials with various unique properties. They are recently attracting enormous interest due to their superiority in water solubility, chemical inertness, low toxicity, ease of functionalization as well as resistance to photo-bleaching and potential applications in biomedical indication, photo-catalysis, energy conversion, optoelectronics, and sensing. In this work, we present a facile and environmentally friendly synthesis of CQDs based on plasma - liquid interaction method. This is a single-step method and does not use toxic chemicals. The size distribution of obtained CQDs is rather uniform at approximately 3 nm. The emission peak of CQDs shifts from 427 nm to 523 nm as the excitation wavelength is varied from 340 nm to 460 nm. The non-equilibrium reactive chemistry of plasma liquid interaction is responsible for acceleration of the CQDs formation process

Synthesis and Optical Characterization of Dye Doped in Ormosil Nanospheres for Bioapplications

Dye-doped ORMOSIL (organically modified silicate) nanoparticles (NPs) have significant advantages over single-dye labeling in signal amplification, photostability and surface modification for various biological applications. The dyes: Rhodamine 6G (R6G) and Rhodamine B (RB) were successfully incorporated into ORMOSIL nanoparticles fabricated by micellar nanochemistry from Trimethoxysilane CH$_3$Si(OCH$_3$)$_3$ precursor. The optical characterization of dye-doped ORMOSIL NPs was studied in comparison with it’s of free dye in solution. The results shown that the photostability of ORMOSIL dye doped nanospheres is much improved in comparison with it’s of dye in solution. Other studies of the photophysical properties such as anisotropy, fluorescence lifetime and energy transfer were also done

An Ontological Approach for Organizing a Knowledge Base to Share and Reuse Business Workflow Templates

International audienceBusiness process models have been used in a lot of enterprise applications. Along with their popularity, the problem of how to create them correctly in terms of semantics and syntax while effectively promoting the reuse of suitable parts of existing models is increasingly interest. This paper describes how to organize a knowledge base to facilitate the shareability and reusability of business workflow templates. We first introduce a repository consisting of business workflow templates which are well-checked at the syntactic and semantic level. An organizational mechanism for control flow-based business workflow templates is therefore provided to ensure an effective search of templates. We then propose a process for developing workflow templates. Thereby for each use case, users can select and modify suitable workflow templates from the knowledge base

Isothermal models of Chromium (VI) adsorption by using Fe3O4 nanoparticles

The ferromagnetic Fe3O4 nanoparticles with the average particle size of about 10 nm were used to adsorb chromium (VI) in aqueous solution. The equilibrium of Cr(VI) adsorption can be achieved at the pH value of 2.5, in the contact time of 120 minutes. The mechanisms of Cr(VI) adsorption were evaluated by 4 isothermal adsorption models Langmuir, Freundlich, Redlich-Peterson, and Temkin. The results showed that all four models are satisfied; especially, Redlich-Peterson is the most suitable model to describe the adsorption kinetic of Cr(VI) on ferromagnetic Fe3O4 nanoparticles

Investigating the leaching performance of ferric chloride solution for metallic alloys resulting from reduction smelting of spent lithium-ion batteries

Smelting reduction of spent lithium-ion batteries (LIBs) produces metallic alloys containing Co, Ni, Cu, Mn, and Fe. Finding suitable reagents in terms of efficiency, economics, and friendly environment for the dissolution of these metals from the alloys is very important for the recovery process of the metals. In this work, the employment of ferric chloride solution for the dissolution of the metals from the alloys was studied. The effect of parameters like FeCl3 concentration, temperature, time, and pulp density on the leaching efficiency of metals was investigated. Our results indicate that ferric ions in the leaching solutions act as oxidizing agents for the dissolution of the metals, while chloride anions as ligands for the formation of the complexes of the dissolved metal ions. The best conditions for the dissolution of full metals were 0.7 mol/L FeCl3, 12.5 g/L pulp density, 22oC, and 30 min. In comparison with HCl or H2SO4 leaching agents, ferric chloride shows some advantages like a decrease in the dosage of acids and oxidizing agents, fast reaction kinetics, and low energy consumption. With its advantages, ferric chloride solution is considered a potential leaching agent in the recovery process of valuable metals from spent LIBs