Springer Science and Business Media LLC

New chemically amended (sodium periodate cellulose nanoparticle (NaIO₄-CNP) adsorbent material was synthesized from dried fibers of cotton. The synthesized NaIO₄-CNP adsorbent material was characterized for functional groups, crystallite size, surface morphology, morphological structure, and particle size) by using Fourier transform infrared (FT-IR), X-ray diffraction (XRD), Scanning electron microscope (SEM), Transmission electron microscope (TEM) and Brunauer Emmett Teller (BET), instruments, respectively. Then it was investigated to eliminate methylene blue (MB) dye from textile secondary runoff wastewater (SERWW). The physicochemical properties of textile SERWW including organic matter (OM) and inorganic nutrients on the removal capabilities of MB dye was investigated. The adsorption mechanism study was shown that Freundlich isotherm fitted with a maximum removal capability (qmax) of 62.91 mg g⁻¹. The elimination kinetic mechanism fits well to pseudo-second-order and its data recommended the materials (NaIO₄-CNP) are effective for wastewater treatment. The MB dye uptake capacities were influenced by the presence of positively charged ions. The NaIO₄-CNP adsorbent indicated excellent reproducibility considered as capable adsorption resources to eliminate MB dye from textile SERWW.

This study presents a GIS analysis model that utilizes high-resolution Digital Elevation Map data to predict the initiation points of debris flow through the overlap of slope stability analysis techniques and rainfall flow analysis. The debris flow that occurred on Mount Woomyun in Seoul, South Korea in 2011 was selected as the case study for comparing and analyzing the prediction model against the actual case. In South Korea, occurrences of debris flow mostly happen during the summer monsoon season. When a substantial amount of rainfall accumulates and heavy rainfall events occur, the pore water pressure within slopes reaches saturation. Consequently, flow is initiated along “temporary streams.” In this study, areas with a combination of low slope stability and abrupt changes in velocity vectors were assumed to have the highest probability of debris flow occurrence due to the overlapping of these factors. The research model was conducted under this assumption. To evaluate the performance of the model, 3D coordinates of the model’s result point, and actual occurrence points were obtained, and a Pearson correlation analysis was conducted to compare them. With these results, R² values of X = 0.9147, Y = 0.8625, and H = 0.8942 were obtained. These high R² indicate a strong correlation between the model’s predictions and actual occurrences.

Automated scarfing of carbon reinforced plastic (CFRP) layers is on its way to support commercial aircraft repair. In the industry, still, the manual scarfing operation is the qualified method. However, automated techniques as milling, laser removal and water jet cutting are in development and showed already good results. Another promising method is vacuum suction blasting (VSB) that was until now in particular used for the roughening of surfaces before adhesive bonding. To find the right adjustment for the parameters many experiments would be necessary accordingly to different CFRP parts with changing layer thicknesses. Simulation is a way to avoid this and to predict the removal result and the settings for the machining parameters. The VSB model uses a pixel method dividing the simulated part surface into smaller volume elements. Experimental data of VSB static blasting spots are the basic for the source matrix. The simulation feeds the matrix with the blasted depth and removal volume for different blasting times. A shifting of columns of the source matrix in the blasting movement direction simulates the movement of the blasting nozzle on the work piece surface. With this, the model can also predict the nozzle feed to remove exactly one complete layer for each scarfing step. In addition, it visualizes the seamless overlapping distance between two blasted tracks. With further adjustments, the model will predict the dynamic removal for varying input parameters such as negative pressure and nozzle distance or blasting agent.

Liquefied natural gas (LNG) is commonly transported by LNG carriers and stored in cargo containment systems. The primary barrier of the MARK III cargo containment system is welded to a closed space with corrugated stainless steel plates. To meet the requirements of excellent sealing and thermal insulation for cargo containment, the welding process of the corrugated plate need to be strictly controlled, which poses a challenge to the development of related welding equipment. In this paper, we present a new five-axis automatic welding robot system used for plasma arc welding on corrugated surfaces. The moment transfer scheme of the dual linkage mechanism makes the rotary movement of the robot more accurate and stable which gives the system with simpler control algorithm and better overall force characteristics. To ensure tracking accuracy, a novel sensing method based on a LASER sensor, two contact sensors, and an angle sensor is proposed to implement multiple functions such as tracking the welding arc length, identifying corrugation shapes, and detecting welding gun posture. Based on the devised tracking sensor system and welding robot, a servo-control system with a surface-tracking welding control algorithm is established. The experimental results show that the robot system's welding speed is about 7 times that of hand welding and the welding qualification rate was 99%, significantly improving welding efficiency and quality as a critical equipment technology in the process of corrugated plate welding.

The biosynthesis of CuO/Cu₂O-NiO nanocomposites with ratios of 90:10, 80:20, and 70:30 was conducted using Ipomoea carnea leaf extract. This study investigates, for the first time, the antioxidant and antibacterial activities of these nanocomposites against 1,1-diphenyl-2-picryl hydroxyl, Bacillus subtilis, Escherichia coli, and Staphylococcus aureus pathogens. The antibacterial effect of 90:10 nanocomposites (NCs A1) was found to be enhanced compared to 80:20 (NCs B1) and 70:30 (NCs C1) due to particle aggregation, significant reactive oxygen species production, uniform quantum size, and ideal crystalline size. However, 70:30 nanocomposites (NCs C1) exhibited high radical scavenging activity (96.40%), surpassing ascorbic acid (98.63%). The current study revealed that Ipomoea carnea plant extract-based 90:10, 80:20, and 70:30 CuO/Cu₂O-NiO NCs work as a new substitute for the currently utilized antibacterial agents, which are answerable for the multi-drug resistance in common bacteria for living beings and also used for biological importance as antibacterial agents in food packaging industries.

As the impacts of climate change continue to be felt around the world, understanding the effects on groundwater quality and quantity has become an important area of investigation. As a global source of water that contributes to preserving the environment, a better understanding of the effect of precipitation seasonal pattern on these systems is crucial; though studies connected to groundwater quality in this era of environmental crisis are at infancy. This study aims to evaluate the effect of precipitation seasonal pattern on groundwater quality in a coal enriched environment of developing city of west African sub-region with particular reference to Enugu, a coal city in Nigeria. Three residential areas (Abakpa, Achara, and Independence Layout) were randomly selected from high, medium, and low neighbourhood densities in the metropolis. Within the period spanning from April 2018 to March 2019, a physiochemical analysis was conducted on twelve deep wells utilizing weighted arithmetic index method. This technique was implemented in order to facilitate the assessment of the degree of water quality by translating a number of variables to just one metric value. The results of the investigation showed that the groundwater resources in the study region are mildly acidic, presumably as a result of the presence of pyrite, which is a byproduct of coal weathering, and chloride-ion-charged rains. Additionally, noticeable distinctions in the properties of water samples were observed between the dry and rainy seasons. Specifically, just 1% of the sampled water had excellent ratings, while 58.3% were considered good, 29.1% were deemed poor, and 8.3% of samples were categorized as very poor. The study concluded that coupled with climate crisis, seasonal precipitation patterns affect groundwater resources by reducing recharge, discharge, and the overall quality of water. These results have important implications for the management of groundwater resources in the region and highlight the need for continued monitoring and assessment of water quality in the face of ongoing environmental changes.

Rice husk (RH), an abundant agricultural residue, was successfully chemically modified and used as a component in reprocessable and biodegradable epoxy thermosets. First, RH was subjected to alkaline treatment to increase the cellulose content followed by succinylation and curing with trimethylolpropane triglycidyl ether to form the thermoset films. The chemical structure of the different intermediates and thermosets was confirmed by Fourier transform infrared spectroscopy. The developed thermoset films had good solvent resistance against common organic solvents and good thermal stability as measured by thermogravimetry with peak temperatures of 347–387 ℃, char residues of 16–20% and limiting oxygen index values of 24–26%, respectively. The films could be thermally reprocessed by hot-pressing with excellent recovery of the mechanical properties (92–96% recovery of tensile stress). Furthermore, 80–84% biodegradation during 150 days under mesophilic home composting conditions was demonstrated by cumulative CO₂ evolution. These results indicate promising potential for the developed RHs thermosets as replacements for petroleum-based plastics in e.g. packaging and agricultural applications.

In this study, emerging soil pollutants in the form of municipal solid waste (MSW) and agricultural waste were converted into biofuel via thermal degradation process. Among various waste-to-energy conversion processes, the pyrolysis of biomass is considered the most significant due to its maximum biofuel yield than other conversion techniques. Individual and co-pyrolysis of MSW and sugarcane residue (SR) as well as its treated variant (TSR) were performed in a lab-setup fixed-bed reactor with and without catalyst. The effect of acid pretreatment and catalytic effects on the pyrolysis process was assessed in terms of product yields and characterization. The acidic pretreatment of SR and catalyst in the pyrolysis process alters the process yield and its composition. The maximum oil yield of 50.5 wt% was achieved by catalytic co-pyrolysis of MSW + TSR + HZSM5, whereas the maximum gas yield of 38.1 wt% was achieved by catalytic co-pyrolysis of MSW + SR + HZSM5. This suggests that intrinsic minerals present in the biomass and MSW, particularly alkali and alkaline earth metals, have a catalytic effect on the devolatilization of organic material and the char cracking event. The pretreatment of biomass showed considerable improvement in the properties of the produced pyrolysis oil and char. Compared to the pyrolysis oil and char obtained from MSW + SR, the oil and char obtained from MSW + TSR + HZSM5 showed a small increment in their heating values. Pretreatment and the catalytic co-pyrolysis process influenced the structure of the pyrolysis oils, increasing the production of phenolic compounds and aromatic hydrocarbons. The amount of gas components in pyrolysis gas, such as CH4, CO2, and CO also changed more according to the feedstock used for the process. Overall, the HZSM-5 catalyst and co-pyrolysis of MSW with pretreated SR enhanced the pyrolysis conversion of waste municipal solids and agricultural wastes into energy-rich products.

The world's nations are searching for renewable and sustainable energy and fuels due to restrictions on carbon discharges and fossil feedstock shortage.. Biomass is a renewable and sustainable resource; and its conversion is one of the research hotspot areas. This review aims to summarize the evidence gained from different methods of converting lignocellulose materials using heterogeneous catalysts. The review summarizes heterogeneous catalysts like carbon-based sulfonated acids, polymeric acids, metal oxides, and solid and magnetic nature acids, including methods to improve functionality and recyclability. The paper also discusses the approaches for enhancing the efficiency of reactions between heterogeneous catalysts and lignocellulose substrates, like ball-milling, microwave irradiation, solid acid interaction, the effect of hydrogen bonding, and CH–pi (π) bond interaction techniques.