This paper is devoted to the determination of the dispersive component of the surface energy of two boron materials such as h-BN and BPO4 surfaces by using the inverse gas chromatography (IGC) at infinite dilution. The specific interactions and Lewis’s acid-base parameters of these materials were calculated on the light of the new thermal model concerning the dependency of the surface area of organic molecules on the temperature, and by using also the classical methods of the inverse gas chromatography as well as the different molecular models such as Van der Waals, Redlich-Kwong, Kiselev, geometric, Gray, spherical, cylindrical and Hamieh models. It was proved that h-BN surface exhibits higher dispersive surface energy than BPO4 material.
The specific properties of interaction of the two boron materials were determined. The results obtained by using the new thermal model taking into account the effect of the temperature on the surface area of molecules, proved that the classical IGC methods, gave inaccurate values of the specific parameters and Lewis’s acid base constants of the solid surfaces. The use of the thermal model allowed to conclude that h-BN surface has a Lewis basicity twice stronger than its acidity, whereas, BPO4 surface presents an amphoteric character.
The maize commodity is of strategic significance to the South African economy as it is a stable commodity and therefore a key factor for food security. In recent times climate change has impacted on the productivity of this commodity and this has impacted trade negatively. This paper explores the intricate relationship between climatic factors and trade performance for the South African maize. Secondary annual time series data spanning 2001 to 2023, was sourced from an abstract from Department of Agriculture, Land Reform and Rural Development (DALRRD) and World Bank’s Climate Change Knowledge Portal. Autoregressive Distributed Lag (ARDL) cointegration technique was used as an empirical model to assess the long-term and short-term relationships between explanatory variables and the dependent variable. Results of the ARDL model show that, average annual rainfall (β = 2.184, p = 0.056), fertilizer consumption (β = 1.919, p = 0.036), gross value of production (β = 1.279 , p = 0.006) and average annual surface temperature (β = −0.650, p = 0.991) and change in temperature for previous years, (β = −0.650, p = 0.991) and the effects towards coefficient change for export volumes, (β = 0.669, p = 0.0007). In overall, as a recommendation, South African policymakers should consider these findings when developing strategies to mitigate the impacts of some of these climatic factors and implementing adaptive strategies for maize producers.
Broad-spectrum antibiotics, such as tetracyclines, are used to treat and manage a range of infectious disorders. Since the kidneys are the primary organs responsible for excreting tetracyclines, clinicians should refrain from prescribing them to patients who have renal failure. Tetracyclines are one of the clinical waste products of today. One of the biggest problems in the field of pollution of the environment today is the persistence of different pharmaceutical residues, drug residues, pesticides, and metal ion species of the new-generation pollutants in surfaces and groundwater. In the present work, carboxymethyl cellulose (CMC)-CuO nanoparticles (CMC-CuO NPs) were synthesized using CuO NPs within different amounts of CMC (0.5, 1.0, 1.5 and 2.0 g) at 85 °C. The synthesized nanoparticles were characterized by XRD, FT IR, SEM, and TG-DTA analysis. According to XRD and SEM, the crystallize size and morphology influenced the dosage of CMC. FT-IR analysis confines the layer of CMC to the CuO nanoparticle surface. TG-DTA results indicated that the CMC content of CMC-CuO NPs was between the range of 69% and 75% by weight. The effects of some parameters such as initial concentration, pH, adsorbent dosage, and contact time on the adsorption of tetracycline from aqueous model solutions on CMC-CuO NPs were investigated with batch studies. It was found that the removal of tetracycline was obtained about 80% with optimized parameters of 10 mg/L concentration, 180 min contact time, 5 pH, and 0.3 g/25 mL dose. The synthesized CMC-CuO NPs nanocomposite may be a promising material for the removal of tetracycline in environmental pollution and toxicology.
This research aims to explain the management of the Cekungan Bandung Urban Area with a focus on three policy formulations, namely process, content and context in the social, environmental and economic dimensions. The research method used is a qualitative approach. Data collection techniques include observation and interviews with stakeholders, using purposive sampling techniques, including the Head of West Java Province Regional Development Planning Agency, district/city Bappeda heads, planners (Badan Perencanaan Dan Pembangunan Daerah, Bappeda), Regional People`s Representative Assembly (Dewan Perwakilan Rakyat Daerah, DPRD members), Legal Bureau and Collaboration Bureau Heads in West Java Province, and Academic Manuscript Compiler. Due to the absence of comfortable, safe, and punctual public transportation, people continue to use private vehicles, leading to unresolved traffic congestion and environmental pollution, thus resulting in economic losses. The results show the formulation of policies for managing the urban area of the Cekungan Bandung, specifically the establishment of BP Cek ban, faced challenges due to a lack of authority in managing financial and human resources. The agency couldn’t execute programs or activities and implement the development due to limitations in legal authority over state finances. Alternative policies were not effectively synchronized between government levels and lacked legislative support, hindered by regional autonomy. The contribution of the research is as reference material for the government in formulating management policies for the Cekubgan Bandung urban area.
Copyright © by EnPress Publisher. All rights reserved.