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51.
Rui Zhang Leng Ni Xiao Di Baitao Ma Shuai Niu Zhihua Rong Changwei Liu 《Molecules (Basel, Switzerland)》2021,26(4)
Carotid artery stenosis (CAS) is an atherosclerotic disease characterized by a narrowing of the artery lumen and a high risk of ischemic stroke. Risk factors of atherosclerosis, including smoking, hypertension, hyperglycemia, hyperlipidemia, aging, and disrupted circadian rhythm, may potentiate atherosclerosis in the carotid artery and further reduce the arterial lumen. Ischemic stroke due to severe CAS and cerebral ischemic/reperfusion (I/R) injury after the revascularization of CAS also adversely affect clinical outcomes. Melatonin is a pluripotent agent with potent anti-inflammatory, anti-oxidative, and neuroprotective properties. Although there is a shortage of direct clinical evidence demonstrating the benefits of melatonin in CAS patients, previous studies have shown that melatonin may be beneficial for patients with CAS in terms of reducing endothelial damage, stabilizing arterial plaque, mitigating the harm from CAS-related ischemic stroke and cerebral I/R injury, and alleviating the adverse effects of the related risk factors. Additional pre-clinical and clinical are required to confirm this speculation. 相似文献
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针对蛇形圆波导变换器尺寸大和带宽窄的不足,提出了变周期蛇形圆波导模式变换器,以实现TE01到TE11模式的高效率转换。根据耦合波方程,编制了优化计算程序,对工作于30.5 GHz、半径为16 mm的变周期以及传统蛇形变换器几何结构分别进行了优化计算,得到了可实现最高模式变换效率的几何参量。计算结果表明:传统结构变换器最优长度长达1 056.97 mm,转换效率98.1%,90%以上转换带宽也仅为3.3%;变周期变换器最优长度为769.53 mm,转换效率为99.3%,90%以上转换带宽为5.9%。变周期结构相对于传统结构的模式变换器具有尺寸小和带宽宽的明显优势。测试表明所提出的模式变换器具有良好的模式变换性能。 相似文献
54.
Jiakang Zhang Xueqing Niu Cheng Peng Haokun Jiang Le Yu Prof. Hong Zhou Prof. Zhongmin Zhou 《Angewandte Chemie (International ed. in English)》2023,62(50):e202314106
The migration of ions is known to be associated with various detrimental phenomena, including current density-voltage hysteresis, phase segregation, etc., which significantly limit the stability and performance of perovskite solar cells, impeding their progress toward commercial applications. To address these challenges, we propose incorporating a polymerizable organic small molecule monomer, N-carbamoyl-2-propan-2-ylpent-4-enamide (Apronal), into the perovskite film to form a crosslinked polymer (P-Apronal) through thermal crosslinking. The carbonyl and amino groups in Apronal effectively interact with shallow defects, such as uncoordinated Pb2+ and iodide vacancies, leading to the formation of high-quality films with enhanced crystallinity and reduced lattice strain. Furthermore, the introduction of P-Apronal improves energy level alignment, and facilitates charge carrier extraction and transport, resulting in a champion efficiency of 25.09 %. Importantly, P-Apronal can effectively suppress the migration of I− ions and improve the long-term stability of the devices. The present strategy sets forth a path to attain long-term stability and enhanced efficiency in perovskite solar cells. 相似文献
55.
Weidong Shang Sheng‐Nan Su Rong Shi Ze‐Dong Mou Guo‐Qiang Yu Xia Zhang Dawen Niu 《Angewandte Chemie (International ed. in English)》2021,60(1):385-390
We here report glycosyl sulfoxides appended with an aryl iodide moiety as readily available, air and moisture stable precursors to glycosyl radicals. These glycosyl sulfoxides could be converted to glycosyl radicals by way of a rapid and efficient intramolecular radical substitution event. The use of this type of precursors enabled the synthesis of various complex C‐linked glycoconjugates under mild conditions. This reaction could be performed in aqueous media and is amenable to the synthesis of glycopeptidomimetics and carbohydrate‐DNA conjugates. 相似文献
56.
POROUS MEMBRANE TEMPLATED SYNTHESIS OF POLYMER PILLARED LAYER 总被引:5,自引:0,他引:5
The anodic porous alumina membranes with a definite pore diameter and aspect ratio were used as templates tosynthesize polymer pillared layer structures. The pillared polymer was produced in the template membrane pores, and thelayer on the template surfaces. Rigid cured epoxy resin, polystyrene and soft hydrogel were chosen to confirm themethodology. The pillars were in the form of either tubes or fibers, which were controlled by the alumina membrane pore surface wettability. The structural features were confirmed by scanning electron microscopy results. 相似文献
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58.
Using potentially bidentate ligands (-SC2H4NH2), we produced [2Fe-2S]+ species of different coordination geometries by fission of [4Fe-4S]2+ complexes. Even though the ligands are monodentate in the cubane complexes, both mono- and bidentate complexes were observed in the [2Fe] fission products through self-assembly because of the high reactivity of the tricoordinate iron sites. The electronic structure of the [2Fe] species was probed using photoelectron spectroscopy and density functional calculations. It was found that tetracoordination significantly decreases the electron binding energies of the [2Fe] complexes, thus increasing the reducing capability of the [2Fe-2S]+ clusters. 相似文献
59.
A Multi‐signal Fluorescent Probe with Multiple Binding Sites for Simultaneous Sensing of Cysteine,Homocysteine, and Glutathione 下载免费PDF全文
Guo‐xing Yin Ting‐ting Niu Ya‐bing Gan Ting Yu Dr. Peng Yin Prof. Hai‐min Chen Prof. You‐yu Zhang Prof. Hai‐tao Li Prof. Shou‐zhuo Yao 《Angewandte Chemie (International ed. in English)》2018,57(18):4991-4994
A novel fluorescent probe was developed by integrating chlorinated coumarin and benzothiazolylacetonitrile and exploited for simultaneous detection of cysteine (Cys), homocysteine (Hcy), and glutathione (GSH). Featuring four binding sites and different reaction mechanisms for different biothiols, this probe exhibited rapid fluorescence turn‐on for distinguishing Cys, Hcy, and GSH with 108‐, 128‐, 30‐fold fluorescence increases at 457, 559, 529 nm, respectively, across different excitation wavelengths. Furthermore, the probe was successfully applied to the fluorescence imaging of endogenous Cys and GSH and exogenous Cys, Hcy, and GSH in living cells. 相似文献
60.
Fabrication and cytocompatibility evaluation for blood‐compatible polyethersulfone membrane modified by a synthesized poly (vinyl pyrrolidone)‐block‐poly (acrylate‐graft‐poly(methyl methacrylate))‐block‐poly‐(vinyl pyrrolidone) 下载免费PDF全文
Fen Ran Haiming Song Lang Ma Xiaoqin Niu Jiayu Wu Weijie Zhang Long Kang Changsheng Zhao 《先进技术聚合物》2016,27(5):591-596
Polyethersulfone (PES) membrane, one of the most important polymeric materials because of its good chemical resistance, thermal stability, mechanical, and film‐forming properties, has already been used in hemodialysis, tissue engineering, and artificial organs. In order to improve the blood compatibility of PES membrane, many amphiphilic block copolymers have been synthesized and used as additives for surface modification. The object of this study is to develop a hydrophilic PES membrane by blending a comblike amphiphilic block copolymer poly (vinyl pyrrolidone)‐block‐poly [acrylate‐graft‐poly (methyl methacrylate)]‐block‐poly‐(vinyl pyrrolidone) [PVP‐b‐P (AE‐g‐PMMA)‐b‐PVP] synthesized by RAFT polymerization. The cytocompatibility performance of PVP‐b‐P (AE‐g‐PMMA)‐b‐PVP modified PES membrane was evaluated, which showed better cytocompatibility compared with that of pristine PES membrane. Endothelial cells cultured on the modified membranes present improved growth in terms of scanning electron microscope observation, MTT assay, and confocal laser scanning microscope observation. These results indicate that the modified membrane has great potential application in blood‐contact fields such as hemodialysis and bio‐artificial liver supports. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献