Synthesis of reduced graphene oxide functionalized with methyl red dye and its role in enhancing photoactivity in TiO2–IL/WO3 composite for toluene degradation

Research on Chemical Intermediates - A nanostructured composite material was produced through sol–gel-assisted ionic liquid (IL) synthesized TiO2, WO3 and functionalized reduced graphene...     

Preparation,characterization, and assessment of cytotoxicity,antioxidant, antibacterial,antifungal, and cutaneous wound healing properties of titanium nanoparticles using aqueous extract of Ziziphora clinopodioides Lam leaves

In recent decades, nanotechnology is growing rapidly owing to its widespread application in science and industry. The aim of the experiment was chemical characterization and evaluation of cytotoxicity, antioxidant, antibacterial, antifungal, and cutaneous wound healing activities of titanium nanoparticles using aqueous extract of Ziziphora clinopodioides Lam leaves (TiNPs@Ziziphora). These nanoparticles were characterized by fourier transformed infrared spectroscopy (FT‐IR), field emission scanning electron microscopy (FE‐SEM), energy dispersive X‐ray spectroscopy (EDS), and UV–visible spectroscopy. The synthesized TiNPs@Ziziphora had great cell viability dose‐dependently (Investigating the effect of the plant on human umbilical vein endothelial cells (HUVECs) cell line) and revealed this method was nontoxic. Then, 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) free radical scavenging test was done to assess the antioxidant properties, which indicated similar antioxidant potentials for TiNPs@Ziziphora and butylated hydroxytoluene. Agar diffusion tests were applied to determine the antibacterial and antifungal characteristics. Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC), and Minimum Fungicidal Concentration (MFC) were specified by macro‐broth dilution assay. The data were analyzed by SPSS 21 software (Duncan post‐hoc test). TiNPs@Ziziphora indicated higher antibacterial and antifungal effects than all standard antibiotics (p ≤ 0.01). Also, TiNPs@Ziziphora inhibited the growth of all bacteria at 2‐16 mg/ml concentrations and removed them at 2‐32 mg/ml concentrations (p ≤ 0.01). In case of antifungal properties of TiNPs@Ziziphora, they prevented the growth of all fungi at 2‐8 mg/ml concentrations and destroyed them at 2‐16 mg/ml concentrations (p ≤ 0.01). In vivo experiment, after creating the cutaneous wound, the rats were randomly divided into six groups: untreated control, treatment with Eucerin basal ointment, treatment with 3% tetracycline ointment, treatment with 0.2% TiO₂ ointment, treatment with 0.2% Z. clinopodioides ointment, and treatment with 0.2% TiNPs@Ziziphora ointment. These groups were treated for 10 days. For histopathological and biochemical analysis of the healing trend, a 3 × 3 cm section was prepared from all dermal thicknesses at day 10. Use of TiNPs@Ziziphora ointment in the treatment groups substantially reduced (p ≤ 0.01) the wound area, total cells, neutrophil, and lymphocyte and remarkably raised (p ≤ 0.01) the wound contracture, hydroxyl proline, hexosamine, hexuronic acid, fibrocyte, and fibrocytes/fibroblast rate compared to other groups. In conclusion, the results revealed the useful non‐cytotoxic, antioxidant, antibacterial, antifungal, and cutaneous wound healing effects of TiNPs@Ziziphora.     

The effect of reaction mixture movement on the performance of chromium-benzenedicarboxylate,MIL-101(Cr), applicable for CO2 adsorption through a new circulating solvothermal synthesis process

Journal of the Iranian Chemical Society - The primary objective of the present work was to investigate the effect of fluid movement on synthesized chromium-benzenedicarboxylate, MIL-101(Cr),...     

Detection of acetone in the human breath as diabetes biomarker based on PPy/WO3 nanocomposite sensor by FFT continuous cyclic voltammetry method

This research represents a novel detection method of acetone level in the exhaled breath samples (RH=88 %) based on polypyrrole/tungsten oxide (PPy/WO₃) nanocomposite sensor. The PPy/WO₃ sensor was fabricated by the deposition of nanocomposite on/between interdigitated electrodes (IDEs) through electrospray coating and was then characterized by FE-SEM imaging. In this detection method, the coulometric signal of the sensor was calculated using Fast Fourier Continuous Cyclic Voltammetry (FFTCCV), where cyclic voltammetry (CV) was applied to the sensor in the defined potential rang and then charge changes of the sensor was obtained by integration of the current in all scanned potential ranges. FFTCCV method enhances the sensitivity of the sensor when exposed to the gas mixtures containing acetone. In addition to its fast coulometric response time (≤5 s) in the two linear ranges of 0.7–2.8 ppm and 2.8–28.2 ppm (R²=0.99), FFTCCV method provides the low detection limit of 70 ppb, and high sensitivity toward acetone at the optimum values of the parameters. The fabricated sensor showed great selectivity toward acetone when exposed to humid air and some exhaled gas like carbon dioxide, ammonia, methanol, ethanol and alkyl amines. The results were very satisfying as the sensor was capable to detect different acetone levels in human exhaled breath as non-invasive diagnosis of diabetes with a good correlation (R²≃0.9) to the routine blood sugar test taken by different commercial glucometers results.     

Amorphous Silicon: New Insights into an Old Material

Amorphous silicon is synthesized by treating the tetrahalosilanes SiX₄ (X=Cl, F) with molten sodium in high boiling polar and non‐polar solvents such as diglyme or nonane to give a brown or a black solid showing different reactivities towards suitable reagents. With regards to their technical relevance, their stability towards oxygen, air, moisture, chlorine‐containing reaction partners RCl (R=H, Cl, Me) and alcohols is investigated. In particular, reactions with methanol are a versatile tool to deliver important products. Besides tetramethoxysilane formation, methanolysis of silicon releases hydrogen gas under ambient conditions and is thus suitable for a decentralized hydrogen production; competitive insertion into the MeO?H versus the Me?OH bond either yields H‐ and/or methyl‐substituted methoxy functional silanes. Moreover, compounds, such as Me_nSi(OMe)_4?n (n=0–3) are simply accessible in more than 75 % yield from thermolysis of, for example, tetramethoxysilane over molten sodium. Based on our systematic investigations we identified reaction conditions to produce the methoxysilanes Me_nSi(OMe)_4?n in excellent (n=0:100 %) to acceptable yields (n=1:51 %; n=2:27 %); the yield of HSi(OMe)₃ is about 85 %. Thus, the methoxysilanes formed might possibly open the door for future routes to silicon‐based products.     

An extended slacks-based measure model for data envelopment analysis with negative data

Data envelopment analysis (DEA) is a non-parametric approach based on linear programming that has been widely applied for evaluating the relative efficiency of a set of homogeneous decision-making units (DMUs) with multiple inputs and outputs. The original DEA models use positive input and output variables that are measured on a ratio scale, but these models do not apply to the variables in which negative data can appear. However, with the widespread use of interval scale data and undesirable data, the emphasis has been directed towards the simultaneous consideration of the positive and negative data in DEA models. In this paper, using the slacks-based measure, we propose an extended model to evaluate the efficiency of DMUs, even if some variables are measured on an interval scale and some on a ratio scale. Moreover, the extended model allows for the presence of all interval-scale variables, which are capable of taking both negative and positive values.     

Electrochemical determination of captopril in the presence of acetaminophen,tryptophan, folic acid,and l-cysteine at the surface of modified carbon nanotube paste electrode

Ionics - A novel carbon paste electrode (CPE) modified with 2,2′-[1,7–heptanediylbis(nitrilomethylidene)]-bis(4-hydroxyphenol) (DHB) and carbon nanotubes (CNTs) was prepared. At first,...