In the present work, coal fly ash-derived mesoporous silica material (CFA-MS) has been successfully fabricated without employing any extra silica source. The obtained CFA-MS was characterized by Fourier transform infrared spectroscopy, nitrogen adsorption–desorption measurement, powder X-ray diffraction and transmission electron microscopy. Nitrogen adsorption–desorption measurement disclosed that CFA-MS possesses Brunauer–Emmett–Teller-specific surface area of 497 m 2 ·g −1 and pore volume of 0.49 cm 3 ·g −1 , respectively. Furthermore, CFA-MS was evaluated for the adsorptive removal of methylene blue from aqueous solution. Several influence parameters on the removal of methylene blue including contact time, pH, initial concentration and temperature were studied in detail. Moreover, Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models were employed for interpretation of the adsorption process, while the pseudo-first-order and pseudo-second-order kinetics equations were applied to investigate the adsorption kinetics. Results in the current work demonstrate that CFA-MS can be used as an efficient adsorbent for methylene blue removal.
Billboards are permanent facilities in large commercial buildings, indoor and outdoor public places, and in fire accidents, billboards will become the main cause of the expansion and spread of fires. To reduce the fire accidents caused by the burning of billboards, this paper conducted experimental tests on 12 commonly used billboard material types of Polyethylene glycol terephthalate (PET) and Polyvinyl chloride (PVC). Among the 12 materials, only PVC4 belongs to the range of flame-retardant materials. PVC6 has the lowest calorific value, less heat release, and a stronger fire effect than other materials. The flammability experiment shows that the ignition time of the material is positively correlated with the combustion height under the same ignition method, and the ignition time is also positively correlated with the combustion width. Under the same ignition time conditions, the flame aspect ratio using edge ignition is greater than or equal to the flame aspect ratio using surface ignition, and the fire hazard is greater. It is necessary to avoid the presence of combustibles around 250 mm to cause fire spread. The monomer combustion experiment shows that the flame spread area of PVC material is much larger than that of PET material. Among all materials, the most dangerous is PVC6, which releases the largest CO concentration and the fastest rate after combustion, produces the most flue gas within 100 after combustion and has poor flame-retardant performance. The combustion of all advertising materials releases less CO and CO2 concentration, which can cause physiological adverse reactions in the human body but will not cause death.
This independent study analyses the relationship between China and Greece, focusing on the Belt and Road Initiative (BRI). It explores the historical and modern diplomatic, economic, and cultural ties between the two countries, as well as the objectives, scope, and current state of cooperation of the BRI. The paper also explores the EU's views and policy responses (e.g., The Global Gateway) to the China-Greece partnership and the BRI, including concerns about the project's potential impact on European unity and sovereignty.
The study used a qualitative research approach, including analysis and summary of existing literature, official documents, plans, activity reports, and press reports. In addition, the study makes recommendations for the better development of Chinese BRI cooperation in Greece, while a more transparent and sustainable approach is needed. It also recommends that China works closely with the EU and Greece and that projects need to be aligned with European standards and regulations.
Overall, this paper provides an in-depth analysis of China's relationship with Greece and its potential impact on the EU, making recommendations for China to strengthen its cooperation with Greece on BRI and to influence the economic and political landscape of the region.
Due to the large number, large size and wide distribution of billboards built-in airport terminals, they easily become ignition sources and fuses that promote the spread of fires after the fire, and such fire hazards are often ignored. To study the spread of airport terminal fires caused by billboards, the combustion test of 12 common billboard materials Polyethylene Glycol Terephthalate (PET) and Polyvinyl Chloride (PVC) was carried out by monomer combustion experiment. Then, the experimental data were substituted into the FDS simulation software to simulate and verify the fire in the airport terminal, and the fire development, smoke diffusion, visibility change, CO generation and temperature change were studied. The results show that the scope of fire spread to the airport terminal after the burning of advertising materials is spatially limited, which is related to the location and height of the fire source of the billboard. The large amount of smoke the fire generates forms an inverted cone plume shape, and the phenomenon of roof jet and smoke settlement will occur. The temperature of the smoke that spreads to the ceiling reaches 300°C, reaching 3/8 of the area on the second floor of the terminal at 700s. The smoke hazard of the floor above the ignition point is much greater than that below the ignition point, and the horizontal spread rate of smoke above the ignition point accelerates with the increase of floor height. Visibility analysis showed that visibility near the roof and near the fire source was low, and the visibility level had little impact on the escape of personnel. As the fire develops, the farther away from the fire source, the faster the CO volume fraction of the floor reaches the critical value. This study provides a theoretical basis and data support for the fire safety assessment of the multi-functional public area of the terminal
Consequently, the industry's adverse effects on the ecological environment have become increasingly apparent [3].According to the latest research by the United Nations World Tourism Organization (UNWTO) [4], the tourism sector contributes to 4.9% of global CO 2 emissions, with a substantial 14% contribution to the global greenhouse effect [3][4][5].Furthermore, the CO 2 emissions from the world tourism industry are escalating at an annual average rate of 2.5%.In 2019, China recorded staggering numbers of 1.28 billion inbound tourists and 3.61 billion domestic tourists [6].Such extensive tourism activities inevitably result
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)