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31.
合成了4,4’-二(间氨基苯氧基)联苯-3,3’-二磺酸(mBAPBDS)单体, 采用红外光谱和核磁共振等方法对其结构进行了表征. 使用mBAPBDS, 2-(对胺基苯基)苯并噁唑-5-胺(APBA)和1,4,5,8-萘四甲酸二酐(NTDA)共聚合成了含有噁唑结构的新型磺化聚酰亚胺(NTDA-mBAPBDS/APBA), 通过控制磺化二胺与非磺化二胺的比例来控制磺化程度. NTDA-mBAPBDS/APBA共聚物表现出较好的溶解性、成膜性能和良好的热稳定性, 其磺酸基团分解温度高于300 ℃. 采用溶液浇铸法制备了磺化聚酰亚胺(SPIs)膜, 对膜的吸水率、溶胀度和质子电导率等性能进行了初步的研究. 结果表明, SPIs膜具有适当的吸水率和良好的尺寸稳定性, 其室温电导率在4.72×10-3和9.60×10-3 S/cm之间, 接近于相同条件下Nafion®117的电导率(9.80×10-3 S/cm). 相似文献
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Yi Wang Xiangli Zhang Wenya Zhuang Yanlei Yu Xuanrong Sun Hong Wang Fengzhi Li Qingyong Li 《Molecules (Basel, Switzerland)》2022,27(12)
Irinotecan and Topotecan are two Camptothecin derivatives (CPTs) whose resistance is associated with the high expression of breast cancer resistance protein (BCRP) and P-glycoprotein (P-gp). To reverse this resistance, two novel CPTs, FL77-28 (7-(3-Fluoro-4-methylphenyl)-10,11-methylenedioxy-20(S)-CPT) and FL77-29 (7-(4-Fluoro-3-methylphenyl)-10,11-methylenedioxy-20(S)-CPT), were synthesized by our group. In this study, the anti-tumor activities of FL77-28, FL77-29, and their parent, FL118 (10,11-methylenedioxy-20(S)-CPT), were evaluated and the results showed that FL77-28 and FL77-29 had stronger anti-tumor activities than FL118. The transport and uptake of FL118, FL77-28, and FL77-29 were investigated in Caco-2 cells for the preliminary prediction of intestinal absorption. The apparent permeability coefficient from apical to basolateral (Papp AP-BL) values of FL77-28 and FL77-29 were (2.32 ± 0.04) × 10−6 cm/s and (2.48 ± 0.18) × 10−6 cm/s, respectively, suggesting that the compounds had moderate absorption. Since the transport property of FL77-28 was passive diffusion and the efflux ratio (ER) was less than 2, two chemical inhibitors were added to further confirm the involvement of efflux proteins. The results showed that FL77-28 was not a substrate of P-gp or BCRP, but FL77-29 was mediated by P-gp. In conclusion, FL77-28 might be a promising candidate to overcome drug resistance induced by multiple efflux proteins. 相似文献
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广角傅里叶变换光谱术研究 总被引:1,自引:0,他引:1
由于采用视场补偿方法,使得傅里叶变换光谱术所允许的立体角更大。本文利用求解积分方程的方法,来对视场补偿的迈克尔逊干涉仪(广角干涉仪)进行光谱复原。 相似文献
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体内细胞组织的缺陷能以皮肤表面所发射红外线的热效应,即细胞组织对称结构点温度漂移值诊断出来,分析缺陷温值的对称性并对其温度值的漂移量进行计算处理,可以临床确诊病变的准确部位。本文即介绍这一诊断系统。 相似文献
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Michael H. Abraham William E. AcreeJr. Xiangli Liu 《Journal of solution chemistry》2018,47(2):293-307
We have set out an equation for partition of 87 neutral molecules from water to o-nitrophenyl octyl ether, NPOE, an equation for partition of the 87 neutral molecules and 21 ionic species from water to NPOE, and an equation for partition of 87 neutral molecules from the gas phase to NPOE. Comparison with equations for partition into other solvents shows that, as regards partition of neutral (nonelectrolyte) compounds, NPOE would be a good model for 1,2-dichloroethane and for nitrobenzene. In terms of partition of ions and ionic species, NPOE is quite similar to 1,2-dichloroethane and not far away from other aprotic solvents such as nitrobenzene. 相似文献
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The interaction of several anti-tumor metal complexes with dGMP have been investigated using trans-[en2Os(η2-H2)]2+ as a 1H NMR probe in a competitive mode. Me2SnCl2, Bu2SnCl2, Et2Sn(phen)Cl2 and Et2SnCl2 can bind to dGMP mainly via phosphate; Cp2TiCl2 binds to dGMP mainly via phosphate and N7. The binding constant for (CH3)2SnCl2 binding to phosphate of dGMP exceeds 2.71×104. The binding constant for Cp2TiCl2 to phosphate is even greater than that of Sn(IV). Cis-platin has high affinity for both N7 and phosphate, but mainly for N7. Binding of the probe to N7 of dGMP reduces the binding affinity for phosphate of the same dGMP molecule by a factor of 5 to 6. Much the same factor is expected to apply to other metals containing agents interacting with dGMP. 相似文献
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