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The purpose of this article is the characterization of permeability and the ideal selectivity of new metallic brass membranes with a “sandwich” structure. Characterization is an important factor related to the morphology, structure, and properties of the membrane. The membranes were examined for simple gas phases, including various exogenous factors on their performance (temperature, pressure, durability). To evaluate their performance, permeate measurements were made at temperatures from -18 to 300°C and at various pressures from 1 to 10 bar. Results have shown that permeability is influenced by the molecular weight and exhibits ideal selectivity greater or equal by Knudsen’s ideal separation factor in a sequence of Η2>He>CH4>N2>O2>Ar≥CO2. The permeability is also a function of the thickness of the membrane, as it shows there’s a decrease in permeability and an increase in selectivity when the thickness is increased. The effect of temperature on these metal membranes is considered an important factor in the operation of membranes and membrane systems. The main feature is the reduction of permeability with the increase of temperature.

Cadmium (Cd) is one of the heavy metal ions and environmental pollutants that can harm humans and other organisms by eliminating serious toxic effects even at low concentrations. Nowadays, the use of this element in various industries has increased its concentration in the environment. Therefore, it is necessary to find appropriate and practical ways to remove it from the environment. The purpose of this study is to evaluate the efficiency of Trichoderma in the absorption of cadmium ions from an aqueous solution by a central composite design (CCD) to optimize the experimental conditions. Analysis of variance (ANOVA) was performed to study the importance and effectiveness of the model. Design specialist software reviewed four independent variables: pH, mixing rate, contact time, temperature, and initial cadmium concentration. A second-order quadratic model was developed to predict the reactions. An ANOVA of cadmium decay in solutions by Trichoderma shows an F-value of 6655.67 for the quadratic model, which indicates that the model is significant. CCD was able to provide a statistical model for predicting response with high accuracy and reliability. Under optimal conditions, the average cadmium decrease (pH = 6, contact time of 120 minutes, initial concentration of cadmium ions of 25° C and 25 mg/L) is approximately 98.8%.

High concentrations of antibiotics have been identified in aqueous media, which has diminished the quality of water resources. These compounds are usually highly toxic and have low biodegradability, and there have been reports about their mutagenic or carcinogenic effects. The aim of this study was to apply zero-valent iron-oxide nanoparticles in the presence of hydrogen peroxide and the sonolysis process for the removal of the amoxicillin antibiotic from aqueous media. In this study, zero-valent iron nanoparticles were prepared by an iron chloride reduction method in the presence of sodium borohydride (NaBH4), and the obtained nanoparticles were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and vibrating-sample magnetometry (VSM). Then, using a Fenton-like process, synthetic wastewater containing 100 to 500 mg/L amoxicillin antibiotic was investigated, and the effects of different parameters, such as the frequency (1 and 2 kHz), contact time (15 to 120 min), the concentration of hydrogen peroxide (0.3%, 0.5%, and 6%), the dose of zero-valent iron nanoparticles (0.05, 0.1, 0.5 g/L), and pH (3, 5, 10) were thoroughly studied. A pH of 3, hydrogen peroxide concentration of 3%, ultrasonic-wave frequency of 130 kHz, zero-valent iron nanoparticles of 0.5 g/L, and contaminant concentration of 100 mg/L were obtained as the optimal conditions of the combined US/H2O2/nZVI process. Under the optimal conditions of the combined process of zero-valent iron nanoparticles and hydrogen peroxide in the presence of ultrasonic waves, a 99.7% removal efficiency of amoxicillin was achieved in 120 min. The results show that the combined US/H2O2/nZVI process could be successfully used to remove environmental contaminants, including antibiotics such as amoxicillin, with a high removal percentage.

Over the past years and present, the expanding number of oil spills occurrences has gotten an overwhelming chemical test to the marine or oceanic environment, and the environmental issues around the globe are becoming more problematic and more acute, be it oil spills or effluents caused by oil and gas or petrochemical industries. The main point of this current investigation is the synthesis of activated carbon (AC) from various agricultural waste materials, bamboo, and banana fibers, as one of the most promising methodologies or applications in treating oil spills constitutes high sorption capacity. The physicochemical feature of the synthesized AC samples was analyzed by FTIR spectra and N2 physisorption. More specifically, the AC samples derived from bamboo (BAMB-AC) at activation temperature 550 ℃ indicate the highest specific surface area (2,760.47 m2/g), and sorption capacity at 3.3678 g/g with the total pore volume, mesopore volume, external surface area being 3.364 cm3/g, 1.811 cm3/g, and 1,601.634 m2/g, respectively, and maximum oil sorption capacity at 4.418 g/g for BANA-AC with activation ratio 7:1 (H3PO4), and surface area at 2,172.234 m2/g.

In this study, the removal of 2-Naphthol Orange dye known as Acid Orange 7 (AO7) from aqueous solutions was studied using a modified adsorbent of wheat bran. The efficiency of neural networks in predicting biological uptake was also investigated. The effect of initial concentration, adsorbent dose, pH, velocity, and mixing time in a discontinuous reactor on the adsorption of 2-naphthol orange dye was investigated. Part of the laboratory results was amplified by a feed-forward-back-propagation neural network, and another part was simulated to measure the accuracy of the model. The transmission function and a number of hidden layer neurons were optimized. Optimum conditions were obtained at an initial concentration of 250 mg/L, an adsorbent dose of 0.07 g/L, a pH of 3, a mixing rate of 200 rpm, and a mixing time of 120 min, with a maximum removal rate of 99% and a maximum adsorption capacity of 92.64 mg/g. The dye adsorption kinetics and adsorption equilibrium (isotherm) were found to follow the quasi-second order and Freundlich model, respectively. In the designed neural network, the best transfer function in the sigmoid tangent function's hidden and output layers and the number of optimal neurons was determined to be 13. The model output had a proper correlation with the target vector (R = 0.986). Also, the simulations performed by the neural network model were in good agreement with the experimental results.

Trifluralin is a widely used herbicide that can be an environmental hazard due to its sensitivity to photodegradation and volatilization to the atmosphere. Using modern techniques, such as microencapsulation, may help maintain trifluralin activity for an appropriate period and reduce applications' quantity and frequency. This work aimed to develop controlled-release formulations of trifluralin by microencapsulation of the active ingredient using interfacial polymerization. The successful encapsulation of trifluralin in the polyurethane network was confirmed by IR and 1HNMR spectroscopy, showing the two compounds' corresponding signals. Dissipation of trifluralin in the microencapsulation and EC formulations were tested with the herbicide exposure to UV light in a reactor for 0, 2, 4, 6, and 8 h. The results showed that the formulation significantly affected herbicide dissipation (P≤0.01). With increasing UV exposure, the active ingredient in the EC formulation decreased linearly and reached 43% after 8 h. In comparison, only 0.9% of the initial herbicide level in the microencapsulation was lost during the same time. Our results indicated that an effective herbicide such as trifluralin can be protected from volatilization and photodegradation by developing a microencapsulation formulation.

Nanotechnology is one of the most attractive disciplines ranging from materials science to biomedicine. It is one of the most prominent areas of research for targeting skin melanoma and other diseases. The application of nanomaterials in the field of skin has increased interest in topical targeting to increase the permeation and retention and reduce its side effects. Different types of nanomaterials have been used for the application of skin diseases and cancer. These nanomaterials include carbon-nanotubes, liposomes, nanoemulsion, nano micelles, etc. In the United States and globally, the prevalence of melanoma has had a growing rise throughout the last 50 years. This review seeks to discuss various types of treatment and diagnosis of early-stage skin cancer. There are many skin cancer biomarkers for early detection of this type of cancer. Diagnosis of skin cancer forms a way of traditional approaches, and their weaknesses are discussed. Electrochemical and optical biosensors for the diagnosis and monitoring of skin cancer are also was described. After all, some issues should be addressed and overcome regarding the competition of new techniques in cost and convenience of use.

The main objective of this work is to try to find potential novel absorbents that could be used for oil spill cleanup. The swelling properties of poplar sawdust were investigated in order to predict its behavior in adsorption with two types of oils (i) diesel and (ii) heating oil. The sorption experiments for sawdust on both diesel and heating oil showed that the prediction obtained by the swelling experiments were correct, and the sawdust exerted good sorption characteristics for both oils. The second part of the experiment focused on synthesizing activated carbon from Aloe vera to check its potential for oil removal. Through BET analysis, characterization showed the high surface area, and FTIR analysis pointed out some possible functional groups. The absorption experiments showed moderate sorption capacity of this material based on diesel experiments and good sorption results with heating oil.

Additive manufacturing is a term used for the type of technologies aiming to manufacture objects by layering materials in specific geometric shapes. 3D printing technology may be financially lucrative; however, safety risks could arise, thus generating different types of potential costs, including economic losses. This work aims to explore such challenges faced by laboratories that use 3D printing technology, emphasizing the relationship between safety and economics in decision-making processes. Qualitative and quantitative methods were thus employed to address the challenges met by laboratories when manufacturing 3D printed biomedical products. The concept of the Total Cost of Ownership (TCO) was used to identify the corresponding costs for Fused Deposition Modelling (FDM) and stereolithography (SLA) by considering the assessment of the processes' accident cost. The quantitative analysis revealed that the most significant parameter impacting the TCO of the FDM and SLA is the labor cost, which comprises over 95% of the total cost. Therefore, reducing 3D printing costs on a lab-scale should be a priority for any 3D process. Other processes can take advantage of the same solution by addressing this issue, thus allowing for more accurate cost comparisons of products created using different processes.