Novel Furochromone Derivatives: Synthesis and Anticancer Activity Studies

Medicinal plant extracts have been used for medical purposes throughout human history. In this study, khellin, having furochromone structure, which is obtained from a well‐known traditional medicinal plant, was selected. A series of furochromonyl compounds ( K1 – K14 ) were synthesized for their anticancer activities. Furochromonyl compounds ( K1 – K14 ) were synthesized by Knoevenagel reaction of substituted 2,4‐thiazolidinediones ( Ia – j )/rhodanines ( Ik – n ) with khellin‐2‐carboxaldehyde ( V ), and their cytotoxicity was investigated in 22 cancer cell lines, which were originated from tissues such as the liver, breast, colon, and cervix. As the first step, two hepatocellular carcinoma cell lines Huh7 and PLC/PRF/5 (Alexander cells) were treated with 10 μM of each compound for 72 h, and then sulforhodamine B assay was performed to analyze their anti‐growth activities. Ethyl 2‐(5‐((4,9‐dimethoxy‐5‐oxo‐5H‐furo[3,2‐g]chromen‐7‐yl)methylene)‐4‐oxo‐2‐thioxothiazolidin‐3‐yl)acetate ( K11 ) was found as the most cytotoxic compound of primary screening. Afterwards, 12 hepatocellular carcinoma, seven breast cancer, two colon cancer, and a cervical cancer cell lines were selected to test K11 for 72 h at multiple concentrations to determine 50% effective doses. Results showed that the 14 cell lines were affected by K11 quantities lower than 10 μM. The structure of K11 , which is particularly effective on breast cancers, can be used to slow down the progression of tumors. Furthermore, the discovery of more effective compounds can be carried out on the basis of this structure.     

Preparation and Characterization of Intercalated Polymethacrylamide/Na‐Montmorillonite Nanocomposites

Polymethacrylamide/Na‐montmorillonite nanocomposites have been prepared by free‐radical polymerization. All the nanocomposites were characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, thermogravimetric analysis, and differential thermal analysis. The thermal properties of nanocomposites are notably improved by the presence of the montmorillonite layers in comparison with pure polymethacrylamide. X‐ray diffraction and scanning electron microscopy confirmed that polymethacrylamide could be easily inserted between the layers of Na‐montmorillonite to form intercalated nanocomposites, and significantly large d‐spacing expansions from 1.19 to 2.93 nm of the nanocomposites. Adsorptive properties of nanocomposites were also investigated.     

A novel proton-exchange porous silicon membrane production method for μDMFCs

This study introduces a new production method to use as a porous silicon-based proton exchange membrane for μDMFCs. In this respect, EIS, fuel crossover test, and fuel cell performance test at the μDMFC sample cell are performed at room temperature on a porous silicon-based membrane that was produced for passive mode μDMFC as a proton exchange membrane. The reason for performing the fuel crossover test is to ensure the silicon opened pores along the silicon wafer and to examine the fuel permeability of the membrane. The fuel crossover test shows that the fuel cell provides energy for about 60 min with a 50 mL fuel. EIS reveals proton permeability of proton exchange membrane. The calculated value of the conductivity of the membrane is 0.0016 S/cm. OCV of the system is 0.4V, whereas values (with highest power density is 0.1 mW/cm²and with the highest current density is 0.39 mA/cm²) are low. However, porous silicon is not a natural proton conductor. Hence, these values can be increased by different ways such as porous silicon functionalized, or serial connection of fuel cells. On the other hand, the value of OCV is consistent with the previous studies. In sum, this study presents a simple, cost-effective, and short time-consuming method for the production of porous silicon as proton-conducting membrane behavior.     

Sol-gel thin films with anti-reflective and self-cleaning properties

Self-cleaning photocatalytic TiO₂ films are beneficial since they reduce the maintenance cost and enhance the efficiency of various optical systems, especially thermal and photovoltaic solar systems. However, the presence of a TiO₂ layer on glass reduces the transmission of incident light, which leads to a decrease in efficiency. This drawback can be overcome by applying a layer of anti-reflective coating beneath the TiO₂ layer. Generally, the anti-reflective layer is porous silica. The presence of the anti-reflective layer compensates for the loss of light transmittance caused by the photocatalytic TiO₂ top layer. This paper reviews some of the previous and the latest fundamental studies in the literature on anti-reflective, self-cleaning and multi-functional films.     

粗硼砂的氯化铵溶液浸提动力学

研究了反应温度、溶液浓度、固液比、固体粒径大小和搅拌速度对氯化铵溶液浸提粗硼砂(十水四硼酸钠,Na₂B₄O₇·10H₂O)动力学的影响。结果表明反应速率随反应温度、溶液浓度的增加和固体粒径、固液比的减小而增加,但搅拌速度对溶解速率无显著影响。根据均相和多相动反应力学模型研究了粗硼砂的溶解过程。结果表明溶解速率遵从假一级均相反应模型。粗硼砂在氯化铵溶液中溶解的活化能为82.73 kJ·mol^-1。     

A New TLC Method for Quantification of Paraquat,Diquat, Difenzoquat,Mepiquat and Chloromequat in Water

JPC – Journal of Planar Chromatography – Modern TLC - We report improved separation of the highly toxic contact herbicides paraquat, diquat, difenzoquat, mepiquat, and chloromequat by...     

An Entry into Obtaining Pyrazole‐, Chromone‐, or Oxadiazole‐Substituted 1H‐Pyrazoles via 2,3‐Furandiones

Some new pyrazole‐, chromone‐, or oxadiazole‐substituted 1H‐pyrazoles were obtained via 2,3‐furandiones. Also, we have presented their plausible mechanisms based on rearrangement; one of these rearrangements is Baker–Venkataraman.     

Effect of acid,water and alcohol ratios on sol-gel preparation of antireflective amorphous SiO2 coatings

Varying amounts of nitric acid catalyst, water and ethyl alcohol were used in the preparation of SiO₂ sols by hydrolysis and condensation reactions of tetraethyl orthosilicate in a one step acid catalysis process. Hydrolysis of TEOS was followed by FT-IR analyses. Size of SiO₂ particles was seen to vary in 8–41 nm range with respect to changing HNO₃ and water amounts in the sols. Gelation occurred in some systems. Surfaces of films were examined by FESEM and AFM, after coating on glass substrates by dip coating. Thicknesses of the films were measured to be in the range of 80–120 nm. 5.6 ± 0.2% point increase in light transmittance was obtained when HNO₃/TEOS (mol/mol) ratio of 4.74 × 10^? 4 and H₂O/TEOS (mol/mol) ratio of 9.08 were utilized. Sols were found to be stable for months and coatings prepared after 45 days still provided 5.2 ± 0.2% point increase in light transmittance.