Preparation of multiwall carbon nanotube/urea-formaldehyde nanocomposite as a new sorbent in solid-phase extraction and its combination with deep eutectic solvent-based dispersive liquid-liquid microextraction for extraction of antibiotic residues in honey.

A solid-phase extraction method combined with deep eutectic solvent-based dispersive liquid-liquid microextraction has been developed for the extraction of three antibiotics in honey samples prior to their determination by ion mobility spectrometry. In this method, first, a multiwall carbon nanotube/urea-formaldehyde nanocomposite was synthesized using co-precipitation polymerization method and then it was used as a sorbent for the analytes extraction from the samples. After that the adsorbed analytes were eluted from the sorbent using a water-miscible organic solvent. The collected elution solvent was mixed with tetrabutylammonium chloride:butanol deep eutectic solvent and the mixture was applied in the following microextraction method. The method provided low limits of detection and quantification in the ranges of 0.32-0.86 and 1.1-2.9 ng/g, respectively. The method had a proper repeatability expressed as relative standard deviation less than or equal to 9.1%. The validated method was successfully performed on different honey samples obtained from different producers.

Is there a relationship between homes' radon gas of MS and non-MS individuals, and the patients' paraclinical magnetic resonance imaging and visually evoked potentials in Yazd-Iran?

Long-term inhalation of radon gas can cause harm to humans and lead to many diseases. One of these diseases is multiple sclerosis (MS), the most common chronic disease of the central nervous system, which alters the brain structure and impedes the rapid transmission of nerve signals throughout the neuron system. Therefore, this study aimed to investigate the relationship of the radon gas concentration in residential homes of MS and non-MS individuals with their results of paraclinical MRI and VEP in Yazd City, Iran. The radon gas concentration was measured in residential homes of 44 people with MS and 100 healthy people. To this end, the questionnaire of radon gas monitoring in residential buildings was administered, and the radon gas concentration was measured by CR-39 detectors. The mean radon concentrations in the homes of MS and non-MS people were 69.51 and 70.83, respectively. A significant positive relationship was found between radon concentration and building's age (P = 0.038). Furthermore, radon concentration had a significant inverse relationship with the building's ventilation (P = 0.053) and cooling systems (P = 0.021). No significant relationship was observed between total radon concentration and MS incidence (P = 0.88). Moreover, no significant correlation was found between radon concentration and location of the plaque in MRI test results of the patients. However, it showed an inverse non-significant correlation with the plaque's number (r = - 0.12, P = 0.42). Further studies in this area are recommended.

Correction to: Improved degradation of n-hexane vapours using a hybrid system, a photoreactor packed with TiO2 coated-scoria granules and a multilayer biofilter.

[This corrects the article DOI: 10.1007/s40201-019-00416-4.].

Improved degradation of n-hexane vapours using a hybrid system, a photoreactor packed with TiO2 coated-scoria granules and a multilayer biofilter.

Biofiltration of hydrophobic and/or recalcitrant volatile organic compounds such as n-hexane is imperfect. In the present study, we applied a hybrid system consisting of a photoreactor packed with scoria granules coated with TiO2 and a biofilter to improve the removal efficiency of n-hexane from the air stream. The experimental results showed that the hybrid system provided higher removal efficiencies than the single biofilter process with an inlet n-hexane concentration range of 0.11-1 g-3 for empty bed residence times (EBRTs) of 30-120 s in the hybrid system. The removal efficiency of the single biofilter in EBRTs of 30, 60 and 120 s was 10.06%, 21.45%, and 45.98%, respectively. When the photoreactor was included as a pretreatment system (with residence time of 7-27 s) and the overall EBRTs of the system was adjusted to 30, 60 and 120 s, the removal efficiency of the hybrid system was increased to 39.79%, 63.08%, and 92.6%, respectively. The mass ratio of carbon dioxide produced as an indicator for n-hexane degradation in the hybrid system and the biofilter alone was 1.9 and 1.28, respectively. Bacterial community analysis with sequence analysis of 16S rDNA in the biofilter biomass revealed that Pseudomonas and Bacillus as predominant bacterial species were responsible for n-hexane biodegradation. Therefore, the application of the hybrid system is advantageous in enhanced n-hexane removal from the air stream.

Effect of casein and inulin addition on physico-chemical characteristics of low fat camel dairy cream.

The effect of the addition of the camel casein fraction on some physico-chemical properties of low fat camel milk cream was studied. Oil-in-water emulsions, 25, 30, and 35 (w/w) fat, were prepared using inulin, camel skim milk, milk fat and variable percentages of casein (1, 2, and 3% w/w). The droplet size, ζ-potential, surface protein concentration, viscosity and surface tension of low fat dairy creams was measured. Cream containing 2% (w/w) casein had better stability. The modifications in physico-chemical properties appeared to be driven by changes in particle size distribution caused by droplet aggregation. The cream containing 2% casein leads to a gradual decrease in droplet size, as the particle size decreased, apparent viscosity increased. When casein concentration increased, ζ-potential decreased due to combination of c terminal (negative charge) with the surface of fat particles but steric repulsion improved textural properties. Cream with 30% fat and 2% casein had the best result.