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991.
Bingbing Wang Hongming Lou Hongli Xu Junpeng Zhao Qiujun Wang Qiao Shi Yonghong Deng 《RSC advances》2018,8(12):6373
In this work, a novel star-comb copolymer based on poly(d,l-lactide) (PDLLA) macromonomer and poly(ethylene glycol)methyl ether methacrylate (PEGMA) was prepared, and the electrochemical properties were studied, with the aim of using it as a solid polymer electrolyte in lithium ion batteries. The six-arm vinyl functionalized PDLLA macromonomer was synthesized by a ring-opening polymerization (ROP) of d,l-lactide and subsequently an acylation of the hydroxy end-groups. A series of free-standing solid polymer electrolyte membranes from different ratios of PDLLA, PEGMA and LiTFSI were prepared through solvent-free free radical polymerization under UV radiation. The chemical structure of the obtained polymers was confirmed by 1H NMR and FTIR. The as-prepared six-arm star-comb solid polymer electrolytes (PDLLA-SPEs) exhibit good thermal stability with Td5%s of ∼270 °C and low Tgs of −48 to −34 °C. The electrochemical characterization shows that the PDLLA-SPEs possess a wide electrochemical window up to 5.1 V with an optimal ionic conductivity of 9.7 × 10−5 S cm−1 at 60 °C at an EO/Li+ ratio of 16 : 1. Furthermore, the all-solid-state LiFePO4/Li cells display extraordinary cycling and rate performances at 60 °C by curing the PDLLA-SPEs directly on the cathode. These superior properties of the six-arm star-comb PDLLA-SPE make it a promising candidate solid electrolyte for lithium batteries.In this work, a novel star-comb copolymer based on PDLLA macromonomer and PEGMA was prepared, and the electrochemical properties were studied, with the aim of using it as a solid polymer electrolyte in lithium ion batteries. 相似文献
992.
A poly(2-(N-morpholine) ethane sulfonic acid)/reduced graphene oxide (RGO) modified glassy carbon electrode (GCE) was prepared using an electropolymerization method, and was characterized by scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). The electrochemical behaviors and simultaneous detection of ascorbic acid (AA), dopamine (DA) and uric acid (UA) at this electrode were studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Tests showed that this electrode exhibited excellent electrocatalytic activity towards the oxidation of AA, DA and UA. The oxidation peak currents of AA, DA and UA were proportional with their concentrations in the ranges 1.0 μM–30 μM (30 μM–100 μM), 0.05 μM–100 μM and 0.1 μM–100 μM, with detection limits of 0.43 μM, 0.0062 μM and 0.056 μM, respectively. In addition, this electrode exhibited an excellent selectivity, reproducibility and stability, and has been successfully used to determine real samples with satisfactory results.A sensitive electrochemical sensor for simultaneously detecting dopamine, ascorbic acid and uric acid. 相似文献
993.
Xiuzhen Wei Xiaoyan Bao Jiawei Wu Cuixia Li Yingying Shi Jinyuan Chen Bosheng Lv Baoku Zhu 《RSC advances》2018,8(19):10396
The rejection behaviors of two different charged composite hollow fiber nanofiltration (NF) membranes for six pharmaceutical molecules, primidone, carbamazepine, sulfamethoxazole, atenolol, sulfadimidine and norfloxacin, were characterized in this study. The saturation adsorption behaviors of the different pharmaceutical molecules on each membrane surface were studied and found to be related to the molecular weight, charge and hydrophilicity of the pharmaceutical molecules. After the pharmaceutical molecules reached adsorption equilibrium, the rejection rates of different NF membranes were characterized. The rejection rates of primidone, carbamazepine, sulfamethoxazole, atenolol, sulfadimidine and norfloxacin by the PEI-NF membrane were 85.6%, 91.8%, 79.9%, 98.1%, 93.3%, and 97.1%, respectively. Meanwhile, the rejection rates of the pharmaceutical molecules by the PIP-NF membrane were 82.2%, 85.4%, 91.5%, 79.1%, 87% and 93.3%, respectively. The influence of feed concentration, operation pressure, temperature, pH and ionic strength on the rejection behaviors of the different charged NF membranes were also studied.The rejection behaviors of two different charged composite hollow fiber nanofiltration (NF) membranes for six pharmaceutical molecules, primidone, carbamazepine, sulfamethoxazole, atenolol, sulfadimidine and norfloxacin, were characterized in this study. 相似文献
994.
Jiyou Zhong Weiren Zhao Lunwei Yang Peng Shi Zifeng Liao Menglong Xia Wenhua Pu Wei Xiao Ligen Wang 《RSC advances》2018,8(24):13054
A series of red-emitting Ca3ZrSi2O9:Eu3+,xBi3+ phosphors was synthesized using a conventional high temperature solid-state reaction method, for the purpose of promoting the emission efficiency of Eu3+ in a Ca3ZrSi2O9 host. The site preference of Bi3+ and Eu3+ in the Ca3ZrSi2O9 host was evaluated by formation energy. The effects of Bi3+ on electronic structure, luminescent properties, and related mechanisms were investigated. The inner quantum yield of the optimized sample increased to 72.9% (x = 0.08) from 34.6% (x = 0) at 300 nm ultraviolet light excitation. The optimized sample (x = 0.08) also showed excellent thermal stability, and typically, 84.2% of the initial emission intensity was maintained when the temperature increased to 150 °C from 25 °C, which is much higher than that without Bi3+ doping (70.1%). The mechanisms of emission properties and thermal stability enhancement, as well as the redshift of the charge transfer band (CTB) induced by Bi3+ doping in the Ca3ZrSi2O9:Eu3+ phosphor, were discussed. This study elucidates the photoluminescence properties of Bi3+-doped Ca3ZrSi2O9:Eu3+ phosphor, and indicates that it is a promising luminescent material that can be used in ultraviolet light-emitting diodes.A red-emitting phosphor Ca3ZrSi2O9:Eu3+,Bi3+ with high quantum yield and thermal stability was developed by introducing Bi3+ as an efficient sensitizer. 相似文献
995.
996.
Mengci He Fanpeng Kong Geping Yin Zhe Lv Xiudong Sun Hongyan Shi Bo Gao 《RSC advances》2018,8(26):14369
Molybdenum disulfide (MoS2) is a promising electrocatalyst for hydrogen evolution reaction (HER), but only edges and S-vacancies are catalytic active sites for the HER. Therefore, it is crucial to increase edge sites and S-vacancies for enhancing the HER activity of MoS2. Here, we report an enhanced HER activity of MoS2 by combing vertical nanosheets and H2 annealing. Compared to horizontal MoS2 nanosheets, pristine vertical MoS2 nanosheets showed better HER activity due to a larger amount of edges. H2 annealing further enhanced the HER activity of vertical MoS2 nanosheets remarkably. Scanning electron microscopy (SEM), X-ray photoelectron spectra (XPS) and electrochemical impedance spectroscopy (EIS) were used to elucidate the enhanced HER activity by H2 annealing. SEM images showed that H2 annealing roughened the MoS2 edges, leading to more edge sites. XPS data revealed the smaller S : Mo ratio after H2 annealing, meaning more S-vacancies. Meanwhile, EIS measurements showed that charge transfer was accelerated by H2 annealing. These findings elaborated the H2 annealing induced enhancement of the HER activity, which were further confirmed by the subsequent re-sulfurization experiment.Vertical configuration and H2 annealing enhanced the hydrogen evolution reaction activity of MoS2 nanosheets. 相似文献
997.
Min Shi Rongshuang Huang Fan Guo Lingzhi Li Yanhuan Feng Zhengjie Wei Li Zhou Liang Ma Ping Fu 《RSC advances》2018,8(27):15207
Fatty acid-binding protein 4 (FABP4) is a key mediator of endoplasmic reticulum (ER) stress and apoptosis in diabetes and atherosclerosis. Studies also confirmed that circulating FABP4 depended on renal function in chronic kidney disease (CKD) and acute kidney injury (AKI) patients. However, the function of FABP4 in AKI remains poorly understood and the aim of this study was to investigate the role of FABP4 in ischemia-reperfusion (I/R)-induced AKI. In the present study, renal I/R injury triggered the high expression of the FABP4 gene and protein in the nucleus and cytoplasm of tubular cells of mouse kidney tissue compared to that of Sham. Pretreatment with BMS309403, a highly selective inhibitor of FABP4 at a dose of 20 mg kg−1 d−1 for 4 d, significantly reduced serum creatinine levels to improve acute renal dysfunction and attenuated renal tubular damage in injured kidneys. Pharmacological inhibition of FABP4 also decreased the number of TdT-mediated dUTP nick-end labeling (TUNEL) positive apoptotic tubular cells, accompanied by the down-regulation of cleaved-caspase-3 expression. Furthermore, oral administration of FABP4 inhibitor resulted in a significant attenuation of ER stress indicated by its maker proteins expression of glucose-regulated protein 78 (GRP78), C/EBP homologous protein (CHOP), and caspase-12 in I/R injured kidneys. In vitro, the increased expression of FABP4 in the human renal proximal tubule cell line (HK-2 cell) was induced by hypoxia followed by reoxygenation (HR) and the FABP4 inhibitor resulted in a significant attenuation of cell apoptosis and ER stress in HR-induced HK-2 cells. In summary, these findings indicated that FABP4 contributed to the pathogenesis of I/R-induced AKI and suggested that the inhibition of FABP4 might be a promising therapeutic strategy for AKI treatment.FABP4 inhibition might attenuate I/R-induced AKI through reducing ER stress and apoptosis. 相似文献
998.
Ali Shoaib Muhammad Waqas Asem Elabasy Xinlai Cheng Qianqian Zhang Zuhua Shi 《RSC advances》2018,8(28):15687
Colloidal delivery systems have been widely used as carriers for controlled delivery of pesticides to improve the efficacy and photostability of natural and semi-synthetic pesticides. In this study, we have synthesized emamectin benzoate nanoformulations (EB + NFs) depending on polymeric nanocapsules (PNC) and two types of the nanosilica, mesoporous nanosilica (MCM-48) and silicon dioxide nanoparticles (SNPs) as carriers for the emamectin benzoate (EB). The fabricated nanoformulations were characterized by using X-ray diffraction analysis, Fourier transform infrared spectroscopy, particle size, zeta potential, morphology, absolute recovery (AR), entrapment efficiency (EE), UV stability and release kinetics. The obtained results showed that the carriers had a remarkable loading ability for EB and improved the EB photostability. The EE% of nanoformulations were 92.84%, 87.45% and 71.19% for emamectin benzoate polymeric nanocapsules (EB + PNC), emamectin benzoate SNPs (EB + SNPs) and emamectin benzoate MCM-48 (EB + MCM-48) respectively. The insecticidal activity of EB + NFs against Plutella xylostella showed that the EB + SNPs was more effective than other EB + NFs and EB alone. The LC50 values were 0.18, 4.03, 8.49 and 11.06 mg L−1 for EB + SNPs, EB + MCM-48, EB + PNC and EB respectively. The obtained results suggest the colloidal delivery systems that used in this study could improve the efficacy and photostability for EB, and they are able to overcome the disadvantage of the natural and semi-synthetic pesticides such as environmental sensitivity and to increase the efficacy of pesticides, which eventually leads to reduce the dosage of pesticides needed, reducing the number of applications required in comparison to conventional formulations.Colloidal delivery systems have been widely used as carriers for controlled delivery of pesticides to improve the efficacy and photostability of natural and semi-synthetic pesticides. 相似文献
999.
1000.