Zero-valent iron is a moderately reducing reagent that is both non-toxic and affordable. In the present work, iron nanoparticles were synthesized using bitter guard leaf extract (Momordica charantia L.) (BGL-Fe NP). Using leaf samples from bitter protectant extract, iron nanoparticles were synthesized with secondary metabolites such as flavonoids and polyphenols acting as capping and reducing agents. Polyphenols reduce Fe2+/Fe3+ to nanovalent iron or iron nanoparticles. Iron nanoparticles were synthesized by reducing iron chloride as a precursor with bitter protective leaf extract in an alkaline environment. The obtained BGL-Fe NPs were calcined for 4 h at various temperatures of 400 °C, 500 °C, and 600 °C. The obtained samples were coded as BGL-Fe NPs-4, BGL-Fe NPs-5, and BGL-Fe NPs-6, respectively. The synthesized BGL-Fe NPs were systematically characterized by XRD, SEM, FTIR, UV-Vis and TG-DTA analysis. The obtained BGL-Fe NPs were then used as an adsorbent to remove the aqueous solution of basic methylene blue (MB) dye. MB concentration was monitored using UV-Vis spectroscopy.
The existence of residential well-being of the locals in the sense of equilibrium-state is a competitive advantage for tourism in a given destination. The rise of overtourism could jeopardize this equilibrium and ultimately the effectiveness of tourism in a vulnerable destination. The research question of the study aimed to answer: what are the spiral dynamics of the multifactorial characteristics of the sense of place that can be mapped under the influence of overtourism. Answering the question draws attention to the sense of place—which can be interpreted as a synonym for local character—of the issues of overtourism and residential well-being. Mapping the mechanism of action of the multifactorial characteristic of locality can help to identify non-supportive functions, to pinpoint the balance point for moving towards a supportive quality, and to answer the “how yes” questions at individual, local and collective levels. The answer to the research question is the result of concluding three district-specific sub-questions. The assessment of the results was based on the content analysis of 251 posts (2017–2021) in the local public Facebook group (supplemented by a questionnaire survey of local residents (2022), 30 in-depth interviews with experts and residents (2022) conducted as part of the cross-sectional research, and 10 additional in-depth interviews with residents (2024) conducted for the last sub-question. The flowchart showing the current state of the district along a negative spiral dynamic, the possibility to turn it in a positive direction, and the mind-map-like summary of local, individual and collective mitigation and solution alternatives supporting the change of direction can be considered as a novel scientific result.
In view of the large energy consumption of the regeneration process in the chemical absorption decarburization process, on the basis of the enrichment classification flow process, the nanoscale ceramic film is used as a new heat exchanger between the enriched liquid and the regeneration gas. The porous ceramic film is capable of coupling thermal-mass transfer to effectively recover part of the water vapor and the heat carried in the regeneration gas, so as to reduce the regenerative energy consumption of the system. The effects of parameters such as regeneration temperature, flow rate, molar fraction of water vapor, and MEA enrichment temperature, flow rate, and MEA concentration of shunt on the hydrothermal recovery effect of ceramic membranes of different pore sizes and lengths were studied by using the heat recovery flux and water recovery rate as the indicators. The results show that the hydrothermal recovery performance of the ceramic membrane increases with the increase of MEA enrichment flow, but decreases significantly with the increase of the enrichment temperature. At the same time, with the increase of regenerative gas velocity and the molar fraction of water vapor in the regenerative gas, the heat recovery flux will increase. The heat recovery performance of the 10 nm ceramic membrane is better than that of the 20 nm ceramic membrane.
The cultivation of sugar beet (Beta vulgaris L.) for table or horticultural purposes is largely carried out in the conventional way which is characterized by intense mechanization causing soil degradation and high labor costs. New cultivation techniques are being employed in the production of vegetables aiming to ensure improvements in environmental and economic conditions, such as the no-till farming system. Thus, the objective of this work was to evaluate the vegetable classification and physicochemical characteristics of beets from different corn planting densities. The experiment was conducted in the period from October 2018 to June 2019 in the municipality of Nova Laranjeiras (PR). Corn was used as a cover plant and the vegetable used was beet cultivar Early Wonder Tall Top. The experimental design used was in interspersed blocks in unifactorial scheme (corn densities 40, 60, 80, 100 thousand plants/ha and control) with four blocks, with plots 3.60 m long and 1.20 m wide. The parameters evaluated 60 days after planting were: commercial classification (class, group, subgroup, category), length, diameter, mass, pulp firmness, soluble solids, titratable acidity, pH and ratio, phenolic compounds. Of which the variables that were not significant at 0.5 probability were length, category (defects), firmness, subgroup (flesh color), soluble solids and phenolic compounds. It is concluded that high densities of corn as mulch for SPDH of sugar beet crop negatively affect the grade and physicochemical characterization of the products.
Introduction: In Colombia, the last oral health study showed that about 70% of the population has partial edentulism while 5.2% will have lost all their teeth between the age of 65 and 79. Rehabilitation with implants is an increasingly used option, which requires clinical and radiographic follow-up. Panoramic radiography is a low-cost option, in which it is possible to observe areas of bone loss, mesiodistal angulation of the implant, relationship with anatomical structures and lesions suggestive of peri-implantitis. Reports and analysis of relevant data on radiographic findings associated with dental implants are required to determine the risk factors for their success in patients who use them. Objective: To determine the prevalence and characterize the findings associated with osseointegration implants in panoramic radiographs. Methods: A descriptive cross-sectional observational study was carried out with 10,000 digital panoramic radiographs selected by convenience from radiological centers in the city of Bogota, Colombia, of which 543 corresponded to the sample analyzed for the presence of implants. The following were evaluated for each implant: location, position, angulation and distances to adjacent structures, using the Clínicalview® program (Orthopantomograph OP200D, Instrumentarium, USA). Results: The frequency of radiographs with implants was 5.43% with a total of 1,791 implants, with an average of 3.2 per radiograph. They were found in greater proportion in the upper jaw with a supracrestal location and an angulation of 10.3 degrees. 32% had implant/tooth or implant/implant distances that were less than optimal. 40.9% were restored and 1.2% showed lesions compatible with periimplantitis. Conclusions: A high percentage of the implants reviewed have a risk factor that affects their long-term viability, either due to angulation, supracrestal or crestal position, proximity to teeth or other implants, or because they are not restorable.
The border is a strategic area within the Republic of Indonesia because it has potential natural resources and market opportunities and is related to aspects of sovereignty, defense and security. The division of the Papua region based on astronomical lines causes the traditional region, inhabited by tribes with the same spiritual-culture, to be divided into two countries. The Kanum tribe, who live in the border region of PNG and Indonesia, have close kinship relations. This research aims to analyze the social interactions of cross-border communities, especially the interdependence of the Kanum Tribe in Sota, Merauke Regency, with Papua New Guinea. The research used social interaction theory and interdependence theory, as well as qualitative descriptive methods by interviewing 15 informants. The research results support Polanyi’s statement but refute Omolomo’s, confirm positive competition, and eliminate indicators of conflict in the social interactions of the Kanum Tribe. The main problem found was unclear population data for the Kanum community who live in PNG but receive facilities from Indonesia. The dominant inhibiting factor comes from the PNG border condition, and the dominant supporting factor comes from the Sota border conditions (geography, infrastructure, economics and government policy). However, the condition that is equally a during factor in the conditions of the PNG and Sota borders is culture.
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