Nanocomposite films of CNPs/CuO structures by electrophoresis method

The article discusses the results of ordering a composite of carbon nanoparticles (CNPs) coated copper oxide (CuO) on the silicon substrate by the electrophoresis method and, particles size and chemical composition have analyzed by Raman spectroscopy, an Atomic Force Microscope, and Scanning Electron Microscope. Carbon nanoparticles from Single-walled Carbon Nanotubes (SWCNTs) using the centrifugation method are applied by a pipette (by the drop method) on the silicon substrate with copper electrodes under the direct electric field to obtain CNPs-CuO nanocomposite films. It has been shown that carbon nanoparticles in solutions upon dispersion in an ultrasonic bath and subsequent centrifugation have a limiting particle size of 38 nm and CNPs solution can be controlled to obtain the nanocomposite films by the electrophoretic forces.

Simultaneous Determination of REEs in Coal Samples Using the Combination of Microwave-Assisted Ashing and Ultrasound-Assisted Extraction Methods Followed by ICP-OES Analysis

The world during the COVID-19 pandemic has led to extensive use of virtual activities by means of electronic devices, which are made up of rare earth elements (REEs). This means that quantitative knowledge of REEs in various resources is crucial for the development of effective recovery methods. Therefore, this report describes a simple microwave assisted ashing followed by ultrasound-assisted extraction (MAA-UAE) for quantitative determination of REEs in coal samples using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Firstly, coal samples were ashed at 55 °C for 4.5 h to form white ashes, which were then treated with dilute HNO3 acid under ultrasonication to enhance the extraction of REEs. The quantitative recoveries (86–120%) of REEs were obtained when 1 mol L−1, 0.1 g, 40 °C, 20 min, and high frequency were applied for [HNO3], sample mass, ultrasonic bath temperature, extraction time, and ultrasonic bath frequency, respectively. The method detection limits of the proposed MAA-UAE method were between 0.0075 and 0.59 µg g−1 with satisfactory precision (<5%). The concentration levels of REEs in South African coals ranged from 1.4 to 105 µg g−1, suggesting that this coal can be a resource for REEs.

Ag2CO3 containing magnetic nanocomposite as a powerful and recoverable catalyst for Knoevenagel condensation

In this paper, the synthesis, characterization and catalytic application of a novel magnetic silica-supported Ag2CO3 (MS/Ag2CO3) with core–shell structure are developed. The MS/Ag2CO3 nanocomposite was prepared through chemical modification of magnetic MS nanoparticles with AgNO3 under alkaline conditions. The structure, chemical composition and magnetic properties of MS/Ag2CO3 were investigated by using VSM, PXRD, FT-IR, EDX and SEM techniques. The MS/Ag2CO3 nanocomposite was used as an effective catalyst for the Knoevenagel condensation under solvent-free conditions at 60 °C in an ultrasonic bath. The recovery and leaching tests were performed to study the nature of the MS/Ag2CO3 catalyst under applied conditions.

Evaluation of bond strength in lithium disilicate ceramics subjected to different times and methods of removal of hydrofluoric acid residues

Objective: To evaluate the bond strength in lithium disilicate ceramics subjected to different times and methods of removal of conditioning residues. Materials and methods: Bonding strength was evaluated in lithium disilicate discs after conditioning with hydrofluoric acid, the samples were subjected to different times and methods of removal: air-water spray, ultrasonic bath with distilled water 2 min, ultrasonic bath with distilled water 4 min, phosphoric acid 2 min, phosphoric acid 4 min. Cylinders were made of flowable composite resin that were positioned on the discs. The samples were subjected to micro-shear tests on a universal testing machine. Results: The two-way ANOVA test and the Pos Hoc Tukey test (p<0.05) revealed that the ultrasonic bath group with distilled water 2 min presented significant difference with respect to the phosphoric acid 4 min; however, it did not present significant difference with respect to the other groups. Conclusion: The ultrasonic bath removal method for 2 min presented the highest value of bonding strength.

Randomized clinical trial of complete denture cleaning methods in residents of care institutions

Aim: To evaluate the efficacy of ultrasonic bath and traditional brushing in the hygiene of complete dentures of dependent residents in long-term care institutions (LTCIs). Methods: A randomized cross-over clinical study was conducted in 17 maxillary complete denture wearers living in LTCIs. Cleaning protocols were brushing or ultrasonic bath, both applied with neutral liquid soap. Biofilm biomass were estimated by MTT reduction assay and specific microbial load (CFU) of Streptococcus spp., Staphylococcus spp. and Candida spp. were quantified by selective and differential culture media. Results: Ultrasound method showed higher percentage reduction of biofilm biomass and specific microbial loads of Streptococcus spp. compared to brushing (p<0.01). Reduction of microbial loads of the other microorganisms were not different between cleaning methods (p>0.05). Conclusions: The ultrasonic bath proved to be a feasible alternative method for the mechanical cleaning of complete dentures in LTCIs.

Protein Extractions from Amphistegina lobifera: Protocol Development and Optimization

Proteins are essential to life, and the evaluation of their content, identification, and modification represents a fundamental assay in biochemistry research. Different analytical techniques and protocols have been specifically designed but have rarely been compared. Here, we test and compare a variety of methodologies and treatments for the quantification of proteins in Amphistegina lessonii, a larger symbiont-bearing benthic foraminiferal species. These analyses specifically include (a) lysis buffer (homemade vs. RIPA), (b) protein assays (Lowry, BCA, and Bradford), (c) ultrasonic bath treatment, and (d) protein staining (silver staining vs. Coomassie blue). On the basis of the comparative outcome, we suggest using the homemade lysis buffer, Lowry or BCA assays, ultrasonic bath treatment, and silver stain to maximize the extraction and characterization of protein for A. lessonii. This protocol might be suitable and extended to other benthic foraminiferal species, including the smaller ones.

ULTRASOUND ASSISTED BIO-DYEING OF SOME TEXTILE MATERIALS WITH BLACK CARROT (DAUCUS CAROTA L.) EXTRACT

"This study has been conducted to find out whether black carrot extract can be used as a dyestuff to dye textile materials. For this purpose, the two most widely used textiles (namely, cotton and wool) have been selected. The extractions from the black carrot were performed directly in the dyebath. An ultrasonic bath at 80 °C for 60 minutes was used to increase extraction efficiency. All the dyeing processes were carried out at 100 °C for 60 minutes, both with and without some metal salts, using two different dye concentrations in 1:1 and 1:10 ratios (material weight:dye extraction volume). Six different metal salts, i.e. K2Cr2O7, CuSO45H2O, FeSO47H2O, SnCl22H2O, ZnSO47H2O, KAl(SO4)2.12H2O, were used in the dyeing processes, according to pre- and simultaneous mordanting methods. After the dyeing processes, the dyed samples’ CIE L*a*b* and color efficiency K/S values were determined by spectrophotometry. The SEM and FTIR data of the fabrics were collected and evaluated at the end of the trials as well. At the same time, perspiration, rubbing, washing and light fastness values of the dyed materials were also assessed. Acceptable fastness test results were obtained for the dyed samples. The findings of the study indicated that the dyeability performance of wool and cotton fabrics with black carrot (Daucus carota L.) extract could be greatly influenced by the mordant used and its application method."