Yttrium(III) Nitrate: A Powerful Catalyst for Green and Rapid Synthesis of Some Supramolecules

A convenient and rapid procedure for the synthesis of calix[4]resorcinarenes as useful supramolecules has been developed via a reaction of aryl aldehydes with resorcinol in the presence of yttrium(III) nitrate under solvent‐free conditions. This eco‐friendly method has many appealing attributes such as excellent yields, short reactions times, and simple work‐up procedures.     

Voltammetric Study and Rapid Quantification of Resorcinol in Hair Dye and Biological Samples Using Ultrasensitive Maghemite/MWCNT Modified Carbon Paste Electrode

Increased concern over the risk resorcinol (RS) pose to ecology and humans, led to its position in European Union Category 1 list of endocrine disruptors. Legal measures restricted RS utilization and hence crucial to monitor its levels in the environment. Herein we report development of highly efficient and economically viable electrochemical sensor for quantitative determination of RS based on 77Maghemite/MultiWall Carbon Nanotube (M/MWCNT) modified carbon paste electrode. M/MWCNT was synthesized via strategic IR irradiation for the first time, a promising approach to overcome other complicated chemical routes. Powder X‐ray diffraction (PXRD), Transmission electron microscopy (TEM), Field emission scanning electron microscopy (FESEM) and Energy dispersive X‐ray (EDX) were used for characterization. Using Differential Pulse Voltammetry (DPV), we report the lowest detection limit at 0.02 μM. The potential application of the sensor was accomplished as a result of excellent recoveries made from real samples fortified with RS. Results indicated the proficiency of the sensor reliable for rapid, onsite monitoring of RS water contamination and in biological matrices.     

粉末活性炭对模拟间苯二酚废水的吸附

在静态条件下,研究了粉末活性炭对间苯二酚废水的吸附效果,通过实验优化了吸附条件,并在最佳处理效果下探究其吸附模式。结果表明,当水样pH值为4,温度30℃,活性炭用量0.3g,振荡时间10m in,振荡速率为120r/m in时,对废水的处理效果最佳。拟合得到活性炭吸附间苯二酚的模式符合F reund lich吸附模式。     

Synthesis of novel benzopyrano[3,2-c]coumarins via tandem base promoted nucleophilic substitution and intramolecular electrophilic aromatic cyclization

Efficient and facile synthesis of 7H-benzopyrano[3,2-c]coumarins has been achieved by mild base promoted reaction of 4-chloro-3-formylcoumarin with diversely functionalized resorcinols. All the products were obtained as pure precipitates from the reaction mixture and the structure of the product was confirmed by X-ray analysis.     

纳米银增敏化学发光体系测定间苯二酚

采用柠檬酸钠包覆化学还原法制备纳米银粒子,将该纳米银粒子加入到碱性鲁米诺-铁氰化钾化学发光体系,体系的化学发光强度明显增强,而间苯二酚的加入能抑制该体系的化学发光,据此建立了流动注射化学发光法定量分析痕量间苯二酚的新方法.考察了鲁米诺、铁氰化钾、氢氧化钠以及纳米银浓度对化学发光体系的影响.在优化的实验条件下,该方法测定...     

Preparation,characterization and applications of polyurethane foam functionalized with resorcinol for quantitative separation and determination of silver(I) and mercury(II) from tap and wastewater

A stable chelating resin matrix was prepared by covalently linking resorcinol with polyurethane foam matrix through a –N=N– group. Preconcentration and determination of trace Ag⁺ and Hg²⁺ ions from samples of different origin, using Res-PUF, were studied. Various conditions influencing the sorption of these metal ions onto Res-PUF were optimized. The kinetics of sorption of the Ag⁺ and Hg²⁺ by Res-PUF were found to be fast, reached equilibrium in few minutes (5–10?min) and followed a first-order rate equation with an overall rate constant k in 0.102 and 0.267/min, respectively. Study of the variation of the sorption of the tested metal ions with temperature yielded average values for ΔG, ΔH and ΔS of ?3.94, ?22.02 and ?58.37, respectively. The mean free sorption energy (E) computed from the Dubinin–Radushkevich (D–R) isotherm was found to be equal to 8.91 kJ/mol, which reflects the chelation sorption process. The capacities of the foam material were 0.15 and 0.07?mmol/g for Ag⁺ and Hg²⁺, respectively. Preconcentration factors of?>?50 were achieved (RSD?≈?5.99). The proposed preconcentration procedure was applied successfully to the determination of trace metal ions in natural and wastewater samples.     

Synthesis of mesoporous tin dioxide via sol-gel process assisted by resorcinol–formaldehyde gel

Tin dioxide is a useful n-type oxide semiconductor used in a variety of applications owing to its superior optical, electrical, and multifunctional properties. Here, we used a network of resorcinol–formaldehyde (RF) gel to synthesize mesoporous tin dioxide via a sol–gel process. The effects of various synthesis parameters on the morphology and mesoporosity of the obtained product were investigated, including aging time of the RF gel, tin-to-formaldehyde molar ratio, resorcinol-to-carbonate molar ratio, and the aging time of the tin/RF mixed gel. Our experimental results showed that the interaction between the network of the RF gel and tin-containing sol is a key factor that affected the structural strength of the porous network and the porosity of the final product. Through control of the interactions in the tin/RF mixed gel we obtained porous tin dioxide materials that could be effectively used to form large-surface area films with desirable mesoporous properties.     

Resorcinarenes的合成及其边缘化学修饰(Ⅱ)

探讨了烷基醛类（丁醛、戊醛、异丁醛）的Ｒｅｓｏｒｃｉｎａｒｅｎｅｓ的合成及其边缘化学修饰（乙酰化、甲基化），研究了烷基取代基对合成的影响，并用ＩＲ，＾１ＨＮＭＲ，ＭＳ和ＵＶ对这些化合物进行了表征。     

Photostabilizing of bisphenol A polycarbonate by using UV-absorbers and self protective block copolymers based on resorcinol polyarylate blocks

Bisphenol A polycarbonate degrades due to sunlight, humidity and oxygen. In this study two possible techniques to stabilize the polymer were compared, i.e. blending of UV-absorbers (UVAs) into the polymer or using block copolymers based on resorcinol polyarylates. Combination of different analysis techniques shows that the protection by UVAs is not as good as by the resorcinol polyarylate block copolymers. The block copolymer rearranges itself through a photo-Fries rearrangement within hours into a UV-absorbing top layer. Two different block compositions were studied, and the copolymer with the highest concentration of resorcinol polyarylate groups shows the best protection.     

1, 2-萘醌-4-磺酸钠分光光度法测定间苯二酚

在pH 13.00缓冲溶液中, 间苯二酚能够催化氢氧根离子与1,2-萘醌-4-磺酸钠反应生成2-羟基-1, 4-萘醌, 其最大吸收波长为454 nm. 间苯二酚质量浓度在0.39～13.21 mg/L范围内与吸光度呈现良好线性关系. 线性回归方程为A=0.01918+0.05703c (×105 mol/L), 相关系数r=0.9981. RSD和检测限分别为1.6%, 0.34 mg/L (3σ/k). 该法能够直接用于水样中间苯二酚含量测定, 回收率在94.3%～106%.