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Materials for the controlled release of nitric oxide (NO) are of interest for therapeutic applications. However, to date, many suffer from toxicity and stability issues, as well as poor performance. Herein, we propose a new NO adsorption/release mechanism through the formation of nitrites on the skeleton of a titanium‐based metal–organic framework (MOF) that we named MIP‐177, featuring a suitable set of properties for such an application: (i) high NO storage capacity (3 μmol mg?1solid), (ii) excellent biocompatibility at therapeutic relevant concentrations (no cytotoxicity at 90 μg mL?1 for wound healing) due to its high stability in biological media (<9 % degradation in 72 hours) and (iii) slow NO release in biological media (≈2 hours for 90 % release). The prospective application of MIP‐177 is demonstrated through NO‐driven control of mitochondrial respiration in cells and stimulation of cell migration, paving the way for the design of new NO delivery systems for wound healing therapy.  相似文献   
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温州市PM_(2.5)中水溶性离子污染特征及来源分析   总被引:3,自引:0,他引:3       下载免费PDF全文
2015年1~12月在温州市区采集448个PM_(2.5)样品,采用离子色谱法分析PM_(2.5)中9种水溶性离子(SO_4~(2-)、NO_3~-、NH_4~+、Cl~-、Na~+、K~+、Ca~(2+)、Mg~(2+)和F~-)的浓度,研究其污染特征、化学组分和来源.采样期间9种水溶性离子总浓度为39.97μg·m~(-3),SO_4~(2-)、NO_3~-和NH_4~+占所测水溶性离子总量的(40.19±10.04)%.离子总浓度的季节变化特征为冬季春季秋季夏季,从空间分布上看,多数季节市站采样点PM_(2.5)中离子总浓度低于南浦、龙湾和瓯海采样点.相关性分析结果显示,PM_(2.5)值与NH_4~+、Ca~(2+)、Na~+、K~+、Cl~-、NO_3~-、SO_4~(2-)浓度显著相关,PM_(2.5)中SO_4~(2-)和NH_4~+的主要结合方式为(NH_4)_2SO_4.硫氧化速率(SOR)和氮氧化速率(NOR)的年均值分别为0.44±0.09和0.13±0.04,表明温州市PM_(2.5)中SO_4~(2-)和NO_3~-主要由二次转化形成.主成分分析结果表明,温州市PM_(2.5)中水溶性离子主要来源于燃煤(火力发电和工业燃煤)、生物质燃烧、机动车尾气以及道路和建筑扬尘.  相似文献   
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将国家设计的“理想课程”转化为学校的“现实课程”,以实现新课程所提倡的教育教学理念,并落实到现实的课堂教学行为中,关键因素在教师。  相似文献   
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A family of ZnII‐based metal–organic coordination polymers (MOCPs) [Zn(L)(imid)2] ( 1 ), [Zn(L)(2,2′‐bpy)] ( 2 ), [Zn2(L)2(Py)3] ( 3 ), [Zn(L)(DPP)]?DMF ( 4 ), [Zn(L)(DPEA)] ( 5 ), [Zn2(L)2(4,4′‐bpy)] ( 6 ), [Zn(L)(3,4′‐DPEE)]?DMF ( 7 ), and [Zn3(L)3(3,4′‐DPEE)2]?DMF ( 8 ) (L=dithieno[3,2‐b:2′,3′‐e]benzene‐2,6‐dicarboxylic acid, imid=imidazole, bpy=bipyridine, Py=pyridine, DPP=1,3‐di(pyridin‐4‐yl)propane, DPEA=1,2‐di(pyridin‐4‐yl)ethane, and DPEE=(E)‐3,4′‐(ethene‐1,2‐diyl)dipyridine) have been rationally designed and generated in the solvothermal reaction systems of the new conjugated thiophene derivative L, Zn(ClO4)2?6 H2O, and seven different aromatic N‐donor co‐ligands separately. These N‐donor compounds were carefully selected and employed in the crystal preparation of the eight MOCPs as structure‐directing co‐ligands owing to their structural specialties and habitual coordination fashions. Among these MOCPs, compounds 1 – 3 are 1D polymers with different chain structures. Compounds 4 , 7 , and 8 are 2D structures, in which 4 has two sets of twofold interpenetrating layers, whereas 7 and 8 are both built from three independent sheets. Compounds 5 and 6 are 3D frameworks, in which 5 exhibits a fivefold interpenetrating diamondoid network, whereas 6 shows a typical twofold interpenetrating pillared layer structure with nanoscale channels. The photoluminescent properties of these MOCPs, including excitation, emission, and radiactive lifetime, have also been investigated to help us tentatively understand their structure–property relationships.  相似文献   
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In order to attain an optimum sterilization treatment to obstetric dressings, a new product made by us, with 60Coγ-ray, the effects of radiation on standard bacteria pseudomonas aeruginosa ATcc27853, Escherichia coli ATcc25922, Staphylococcus aureus ATcc25923, Clostridium PB6KA, short Bacillus E60163202 and HBSAg were studied. Results showed that at the absorbed dose of 10 kGy, all the bacteria, bacillus and HBSAg were killed off, and sterilized with the dose, the dressings can completely accord with the demands of hygiene, which was further confirmed by microbiological and poisonous tests and the effects of clinical application. In Nov. 1988, the dressings was awarded the excellent prize in the 1st international exhibition of patent, new technique and new equipment in Guangzhou; its effective application is also reported in the paper.  相似文献   
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Direct electrochemical imidation of aliphatic amines via anodic oxidation   总被引:1,自引:0,他引:1  
Direct electrochemical synthesis of sulfonyl amidines from aliphatic amines and sulfonyl azides was realized with good to excellent yields. Traditional tertiary amine substrates were broadened to secondary and primary amines. The reaction intermediates were observed and a reaction mechanism was proposed and discussed.  相似文献   
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